Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Kim, K." wg kryterium: Autor

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-100 z 100
    Tytuł:
    Analysis Of Drilling Of A Metal Plate With Pilot Hole
    Analiza wiercenia metalowej płyty z otworem pilotującym
    Autorzy:
    Kim, K. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/354541.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    finite element method
    drilling
    pilot hole
    cutting force
    plastic strain
    metoda elementów skończonych
    wiercenie
    otwór pilotujący
    siła cięcia
    odkształcenie plastyczne
    Opis:
    This paper performed a numerical analysis study of the cutting characteristics when drilling a taper hole whose upper and lower diameters are different, that is, a pilot hole. 3-dimensional drilling analysis was performed using a commercial code, and these results were used to determine analytically and compare the cutting temperature, the phenomenon of cutting chip formation, deformation and pressure, etc., for the tools, chips, and specimens during cutting. Also, cutting force and the required energy were calculated and compared. To verify the results of analysis, a cutting dynamometer was used to analyze 3-axis cutting force. Results of analysis showed that the specimen maintained a temperature of approximately 650°, with rapid cooling after chips were formed from the specimen. The tool reached a maximum of 700°, similarly to the chips. It is expected that these results will be utilized to optimize cutting processes and work conditions when drilling holes.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1307-1310
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Distribution and Management of the Invasive Exotic Species Ambrosia Trifida and Sicyos Angulatus in the Seoul Metropolitan Area
    Autorzy:
    Kim, K. D.
    Powiązania:
    https://bibliotekanauki.pl/articles/124560.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Inżynierii Ekologicznej
    Tematy:
    Ambrosia trifida
    exotic
    invasive
    management
    Sicyos angulatus
    spreading
    urban ecosystem
    Opis:
    We investigated the status of invasive exotic plants disturbing the ecosystem of the Seoul metropolitan area and examined the management of such plants. We selected our study sites based on those used in previous studies and on information in databases. All flora were classified into 57 families and 211 species; we evaluated 253 plant communities. The representative, invasive exotic species were Sicyos angulatus, Lactuca scariola, Ambrosia trifida, Ambrosia artemisiifolia, and Eupatorium rugosum. Stands of A. trifida ranged in area from 214 to 16,882 m2 and were present in riparian zones, road and forest edges, slopes, and other open habitats at all sites, covering an average of 37.87% of all study areas. In Gwangju, Ansan, and Anyang cities and in Yeoncheon-gun, A. trifida coverage was >50%; the total mean coverage was near-continuous along the Han and the South Han rivers, broken only by cliffs in some riparian zones, and anthropogenic constructions. A. trifida and S. angulatus require careful management because of extensive growth, shading, and twining. The biodiversity of native species may be conserved by physical eradication of these plants. We describe the extents and distribution patterns of these two representative invasive exotic species in the enormous urban ecosystem of Seoul.
    Źródło:
    Journal of Ecological Engineering; 2017, 18, 5; 27-36
    2299-8993
    Pojawia się w:
    Journal of Ecological Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An integrated framework for various operation plans in container terminals
    Autorzy:
    Won, S. H.
    Kim, K. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/258792.pdf
    Data publikacji:
    2009
    Wydawca:
    Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
    Tematy:
    container terminals
    planning
    resource capacity
    Opis:
    This study provides a framework for integrating various planning activities in container terminals. First, we introduce various planning activities in container terminals and identify decision-making problems for each planning activity. Input parameters, decision variables, objectives, constraints, time buckets, and the planning horizon for each decision activity are identified. Next, we introduce the concept of a resource profile and planning procedure simultaneously by considering availabilities of various resources and resource requirements in a planning activity.
    Źródło:
    Polish Maritime Research; 2009, 3; 51-61
    1233-2585
    Pojawia się w:
    Polish Maritime Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Surface Property of Indium Tin Oxide (ITO) After Various Methods of Cleaning
    Autorzy:
    Kim, K.
    Ihm, K.
    Kim, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/1401317.pdf
    Data publikacji:
    2015-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    73.20.-r
    Opis:
    We investigated the surface property change of indium tin oxide (ITO) with the various cleaning methods, using photoemission spectroscopy (PES), work function change and near-edge X-ray adsorption fine structure (NEXAFS). The detergent treatments of ITO with acetone (C₃H₆O), methanol (CH₄O), 2-propanol (C₃H₈O), and deionized (D) water yielded work function shifts as high as 0.99 eV compared to the no-treatment ITO. In contrast, work function shifts of 0.10-0.35 eV were measured after other treatments. The lowest C 1s concentration was obtained after O2 plasma treatment of ITO. There was no big change in the peak position and the shape of $In 3d^{5//2}$, and $Sn 3d^{5//2}$ after each treatment. But C 1s and O 1s spectra shows a peak shift and shape change. Presence of carbon can be minimized by NaOH treatment combined with oxygen plasma. In NEXAFS spectra of C K-edge on each sample, we found two π-binding states whose positions are 284.5 and 287.9 eV, C=C and C=O, respectively.
    Źródło:
    Acta Physica Polonica A; 2015, 127, 4; 1176-1179
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis Of The Extrusion Process Of A Square Tube Multi-Channel Heat Pipe
    Analiza procesu wytłaczania wielokanałowych ciepłowodów o kwadratowym przekroju
    Autorzy:
    Kim, K. S.
    Kim, J. Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/353935.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminum hot extrusion
    FE simulation
    stress analysis
    extrusion experiment
    aluminium wytłaczane na gorąco
    symulacja FE
    analiza naprężeń
    wytłaczanie
    Opis:
    Heat pipes have been recently in use for cooling purposes in various fields, including electronic circuit boards and vehicle parts that generate large amounts of heat. In order to minimize the loss of heat transferred, there is a need to maximize the contact area of the working fluid. This study produced a square tube multi-channel heat pipe to replace the existing circular pipe type to maximize the internal surface area thereof. This expands the surface, allowing the working fluid to come into contact with a wider area and enhancing thermal radiation performance. A mold for the production for such a product was designed, and finite element simulation was performed to determine whether production is possible.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1463-1466
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Xenoxylon synecology and palaeoclimatic implications for the Mesozoic of Eurasia
    Autorzy:
    Oh, C.
    Philippe, M.
    Kim, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/945484.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    paleontology
    fossil wood
    Xenoxylon
    phytocoenosis
    paleoecology
    paleoclimate
    Mesozoic
    Eurasia
    Opis:
    The distribution of fossil wood genera has been demonstrated to be an effective proxy for Mesozoic terrestrial climates. In this study, we investigated the phytocoenoses, which were associated with Xenoxylon confirmed to be a marker for a cool and/or wet climate in a boreal hemisphere (i.e., Xenoxylon-phytocoenoses) during the Mesozoic, using specimens of fossil wood. It was confirmed that Xenoxylon co-occurs more often with some wood genera than with others. For example, Protocedroxylon, a wood that is most likely related to the Pinaceae, is the genus most often associated with Xenoxylon-phytocoenoses. Although Taxodioxylon is also found in Xenoxylon-phytocoenoses, it is not found, however, as consistently as Protocedroxylon. The distribution and diversity of Xenoxylon-phytocoenoses changed throughout the Mesozoic. During the Late Triassic and Late Cretaceous, Xenoxylon-phytocoenoses had low diversity and were restricted to higher palaeolatitudes during the Late Cretaceous. However, during the Early to Middle Jurassic, Xenoxylon-phytocoenoses were distributed much farther south, while their diversity concomitantly increased sharply. From the Late Jurassic to the Early Cretaceous, the distribution of Xenoxylon phytocoenoses moved northward in Europe and even more so in East Asia. The changes in the distribution of Xenoxylon-phytocoenoses are in agreement with changes in both global and regional climates. Our results also demonstrated that, within the Xenoxylon distribution range, the corresponding phytocoenoses were differentiated along a latitudinal gradient and according to the global climate change patterns during the Mesozoic.
    Źródło:
    Acta Palaeontologica Polonica; 2015, 60, 1; 245-256
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Electroless Ni–P Plating on the Bonding Strength of Bi–Te-Based Thermoelectric Modules
    Autorzy:
    Kim, S. S.
    Son, I.
    Kim, K. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/356583.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    thermoelectric
    Ni–P plating
    bonding strength
    Bi–Te
    soldering
    Opis:
    In the present study, electroless Ni–P plating was applied to Bi–Te-based thermoelectric materials as a barrier layer and the effect of the Ni–P plating on the bonding strength of the thermoelectric module was investigated. The bonding strength of the n- and p-type modules increased after being subjected to the electroless Ni–P plating treatment. In the case of the thermoelectric module that was not subjected to electroless Ni–P plating, Sn and Te were interdiffused and formed a brittle Sn–Te-based metallic compound. The shearing mostly occurred on the bonding interface where such an intermetallic compound was formed. On the other hands, it was found from the FE-EPMA analysis of the bonding interface of thermoelectric module subjected to electroless Ni-P plating that the electroless Ni-P plating acted as an anti-diffusion layer, preventing the interdiffusion of Sn and Te. Therefore, by forming such an anti-diffusion layer on the surface of the Bi–Te based thermoelectric element, the bonding strength of the thermoelectric module could be increased.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1225-1229
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A study of the local entropy generation rate in a porous media burner
    Autorzy:
    Mohammadi, I.
    Esfahani, J. A.
    Kim, K. C.
    Powiązania:
    https://bibliotekanauki.pl/articles/38597672.pdf
    Data publikacji:
    2020
    Wydawca:
    Instytut Podstawowych Problemów Techniki PAN
    Tematy:
    porous media burner
    chemical kinetics
    volumetric heat transfer
    axisymmetric combustion
    local entropy generation
    excess air ratio
    Opis:
    In this paper, the work and performance of the premixed methane-air porous axisymmetrical burner have firstly been simulated numerically using the CFD tools. For this purpose the set of governing equations has been enriched by an additional energy equation in porous solid, and the chemical species transport has been extended onto the multi-step mechanism (GRI-2-11). This numerical model has been verified on the base of available benchmark experiments. Next, we have studied the local entropy generation problem taking into account not only classical contributions like viscous and turbulent dissipation but also, the porous combustion of gases. The results showed that the greatest portion of entropy generation in the porous medium burner is related to chemical reactions, followed by heat transfer, mass diffusion (mixing) and friction (viscous dissipation), respectively. According to the results, as the excess air ratio increases, the local entropy generation rate due to heat transfer and friction increases and the local entropy generation rate due to chemical reactions is decreased. Also, by increasing the volumetric heat transfer coefficient, the local entropy generation rate due to heat transfer decreases and the local entropy generation rate due to friction and chemical reactions increases. Also, the local entropy generation rate due to mixing does not show a significant change with the changing excess air ratio and volumetric heat transfer coefficient.
    Źródło:
    Archives of Mechanics; 2020, 72, 3; 257-279
    0373-2029
    Pojawia się w:
    Archives of Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Maritime traffic characteristics in waterway with time variant CPA
    Autorzy:
    Jeong, J.S.
    Park, G.K.
    Kim, K. I.
    Powiązania:
    https://bibliotekanauki.pl/articles/320550.pdf
    Data publikacji:
    2013
    Wydawca:
    Polskie Forum Nawigacyjne
    Tematy:
    maritime traffic management
    operation rate
    risk assessment
    collision
    CPA
    TCPA
    Opis:
    This paper aims at evaluating the collision risk between the encountering vessels under time- -variant CPA situations and then assessing the maritime traffic characteristics. Radar and AIS data are collected from Mokpo VTS in Korea. All crossing vessels that are navigating within CPA 1 miles of Mokpo-Gu waterway are analyzed. The maritime traffic characteristics is analyzed by surveying the distribution of CPA as a function of TCPA. To make it clear, the traffic operating rate in the Mokpo waterway is also computed. The averages of CPA and TCPA were observed until the encountered vessels pass safety each other after they come in a certain ship domain. As a consequence, the distribution of CPA as a function of TCPA gives a useful information to evaluate the maritime traffic safety.
    Celem artykułu jest ocena ryzyka kolizji statków w funkcji zmiany wartości czasu do kolizji, a na tej podstawie oszacowanie charakterystyk determinujących ruch morski. Dane z radarów oraz systemu AIS zostały zarejestrowane w systemie VTS Mokpo w Korei. Przeanalizowano wszystkie przypadki przecinania się tras statków na podejściu do Mokpo-Gu w przypadku, gdy odległość minimalna (CPA) była mniejsza niż jedna mila morska. Charakterystyka ruchu morskiego opisana została poprzez wyznaczenie rozkładu wartości największego zbliżenia statków jako funkcji czasu do nadmiernego zbliżenia (TCPA). Dla pełnej jasności obliczono również współczynnik przepustowości drogi wodnej Mokpo. Opisano średnie wartości odległości największego zbliżenia oraz czasu do wystąpienia CPA bez względu na przekroczenia granic domeny obserwowanych statków. W konsekwencji wyznaczono rozkład wartości CPA jako funkcję TCPA, co okazuje się użyteczne dla oceny bezpieczeństwa ruchu morskiego.
    Źródło:
    Annual of Navigation; 2013, 20; 49-58
    1640-8632
    Pojawia się w:
    Annual of Navigation
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A mixed control chart adapted to the truncated life test based on the Weibull distribution
    Autorzy:
    Khan, N.
    Aslam, M.
    Kim, K.-J.
    Jun, C. -H.
    Powiązania:
    https://bibliotekanauki.pl/articles/406432.pdf
    Data publikacji:
    2017
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    life test
    Weibull distribution
    attribute chart
    binomial distribution
    average run length
    Opis:
    The design of a new mixed attribute control chart adapted to a truncated life test has been pre-sented. It was assumed that the lifetime of a product follows the Weibull distribution and the number of failures was observed using a truncated life test, where the test duration was specified as a fraction of the mean lifespan. The proposed control chart consists of two pairs of control limits based on a binomial distribution and one lower bound. The average run length of the chart was determined for various levels of shift constants and specified parameters. The efficiency of the chart is compared with an existing control chart in terms of the average run length. The application of the proposed chart is discussed with the aid of a simulation study.
    Źródło:
    Operations Research and Decisions; 2017, 27, 1; 43-55
    2081-8858
    2391-6060
    Pojawia się w:
    Operations Research and Decisions
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Systematic Procedure for Modeling Usability Based on Product Design Variables: A Case Study in Audiovisual Consumer Electronic Products
    Autorzy:
    Kim, K.-J.
    Han, S. H.
    Yun, M. H.
    Kwahk, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/90811.pdf
    Data publikacji:
    2002
    Wydawca:
    Centralny Instytut Ochrony Pracy
    Tematy:
    usability evaluation
    human interface elements
    consumer electronic products
    produkty przemysłowe
    ocena zgodności wyrobów
    ocena użyteczności
    produkty elektroniczne
    Opis:
    A systematic modeling approach to describing, prescribing, and predicting usability of a product has been presented. Given the evaluation results of the usability dimension (UD) and the measurement of the product’s design variables, referred to as the human interface elements (HIEs), the approach enables one to systematically assess the relationship between the UD and HIEs. The assessed relationship is called a usability model. Once built, such a usability model can relate, in a quantitative manner, the HIEs directly to the UDs, and thus can serve as an effective aid to designers by evaluating and predicting the usability of an existing or hypothetical product. A usability model for elegance of audiovisual consumer electronic products has been demonstrated.
    Źródło:
    International Journal of Occupational Safety and Ergonomics; 2002, 8, 3; 387-406
    1080-3548
    Pojawia się w:
    International Journal of Occupational Safety and Ergonomics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of Loading Time of a Load Plate and Sample Size on the Measurement of Physical Properties of Resilient Materials
    Autorzy:
    Kim, K.-W.
    Yeon, J.-O.
    Yang, K.-S.
    Kim, M.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/178069.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    resilient materials
    dynamic stiffness
    compressibility
    long-term deformation
    Opis:
    This study investigates several factors that have not been specified in the standard for dynamic stiffness, compressibility, and long-term deformation; these factors can be used to evaluate the acoustic and physical performances of resilient materials. The study is intended to provide basic data for deriving the factors that need to be additionally reviewed through the standards. Since magnitude of dynamic stiffness changes with an increase in loading time, it is necessary to examine the setting of the loading time for a load plate under test conditions. Samples of size 300×300 mm, rather than 200×200 mm, yielded more reliable results for compressibility measurement. Since the test to infer long-term deformation of resilient materials after a period of 10 years in some samples showed variation characteristics different from those specified in the standards, it is recommended that the test method should be reviewed through ongoing research.
    Źródło:
    Archives of Acoustics; 2015, 40, 2; 159-167
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effects Of Environmental Factors On The Dispersion Behavior Of Iron Oxide In Aqueous Solutions With Poly Acrylic Acid
    Wpływ parametrów charakteryzujących wodne roztwory poli(kwasu akrylowego) na dyspersję tlenku żelaza
    Autorzy:
    Lee, E.-H.
    Kim, K.-M.
    Maeng, W.-Y.
    Hur, D.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/354513.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    polyacrylic acid
    dispersion stability
    magnetite
    nanoparticles
    suspension
    poli(kwas akrylowy)
    stabilność dyspersji
    magnetyt
    nanocząstki
    zawiesina
    Opis:
    After preparing aqueous suspensions from magnetite particles with a poly-acrylic acid, we investigated the effects of several experimental parameters. We characterized the stability of the suspensions using visual inspection, sedimentation, adsorption, and thermal stability of the dispersant. The dispersion stability is affected by the solution pH, the concentrations of magnetite particles, the molecular weight, the concentration of the dispersants, and the temperature. The stability of the suspensions increased as the concentration of the dispersant and the temperature increased. In terms of the molecular weights of the dispersant, the suspensions with dispersant of low-molecular weight (1800) were more stable than those of high-molecular weight (250000) at room temperature. However, at high temperature the suspensions with high-molecular weight showed stability. The adsorption efficiency of the dispersant was very low. The dispersant of high-molecular weight showed a higher thermal integrity than that of low-molecular weight. From this work, we obtained the optimum conditions for stable aqueous suspensions of magnetite particles.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1561-1564
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Preparation Of Fine Grained SiC At Reduced Temperature By Two-Step Sintering
    Wytwarzanie drobnoziarnistego SiC w obniżonej temperaturze przez dwuetapowe spiekanie
    Autorzy:
    Kim, K.-W.
    Oh, K.-S.
    Lee, H.
    Kim, B. S.
    Chung, T.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/353772.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    SiC
    liquid phase
    two step sintering
    coarsening
    hardness
    faza ciekła
    spiekanie dwuetapowe
    odporność
    twardość
    Opis:
    Two-step sintering route was applied for the densification SiC by promoting the role of liquid phase. The specimen contained 8 vol% of liquid phase composed of Al2O3 and Y2O3. The heating schedule consisted with initial rapid heating to 2000°C and immediate quenching to 1700 or 1750°C. By heating at elevated temperature, even distribution of the liquid phase was intended. The heat treatment at reduced temperature was to suppress the evaporative loss of the liquid and to secure the time for densification. The two-step sintering effectively suppressed loss of mass and coarsening. The resultant SiC was thus dense and was composed of fine grains exhibiting hardness of 2321 kgf/mm2.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1539-1542
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Surface Characterization of Metallic Fuel Slugs Prepared by Modified Injection Casting
    Autorzy:
    Mun, S.-U.
    Kim, K.-H.
    Oh, S.-J.
    Park, J.-Y.
    Hong, S.-I.
    Powiązania:
    https://bibliotekanauki.pl/articles/351428.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sodium-cooled fast reactor
    metallic fuel slug
    U-Zr alloy
    surface characterization
    injection casting
    Opis:
    Metallic fuel slugs containing rare-earth (RE) elements have high reactivity with quartz (SiO2) molds, and a reaction layer with a considerable thickness is formed at the surface of metallic fuel slugs. The surface characterization of metallic fuel slugs is essential for safety while operating a fast reactor at elevated temperature. Hence, it is necessary to evaluate the surface characteristics of the fuel slugs so that chemical interaction between fuel slug and cladding can be minimized in the reactor. When the Si element causes a eutectic reaction with the cladding, it deteriorates the metallic fuel slugs. Thus, it is necessary to examine the characteristics of the surface reaction layer to prevent the reaction of the metallic fuel slugs. In this study, we investigated the metallurgical characteristics of the surface reaction layer of fabricated U-10wt.%Zr-Xwt.%RE (X = 0, 5, 10) fuel slugs using injection casting. The results showed that the thickness of the surface reaction layer increased as the RE content of the metallic fuel slugs increased. The surface reaction layer of the metallic fuel slug was mainly formed by RE, Zr and the Si, which diffused in the quartz mold.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 1049-1053
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of Antireflection Structures as a Protective Layer of Solar Cells with Nanoporous Silica Films and Nanoimprinted Moth-Eye Structure
    Autorzy:
    Kim, K.
    Han, J.
    Jang, J.
    Choi, C.
    Choi, S.
    Kim, C.
    Kye, H.
    Cheong, I.
    Powiązania:
    https://bibliotekanauki.pl/articles/1492625.pdf
    Data publikacji:
    2011-12
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    61.46.-w
    68.37.-d
    68.55.-a
    78.20.-e
    Opis:
    The antireflection structures are fabricated by sol-gel process as a protective layer of solar cells and by hot embossing process with anodized aluminum oxide membrane template on polycarbonate film. The optical properties and morphology of the antireflection structures are analyzed by UV-visible spectroscopy and field emission scanning electron microscopy, respectively. The total conversion efficiency of a polycrystalline Si solar cell module with the protective layer, sol-gel-derived nanoporous antireflection structure, is increased by 2.6% and 5.7% for one-side antireflection coated prismatic matt glass and both-side antireflection coated prismatic matt glass, respectively.
    Źródło:
    Acta Physica Polonica A; 2011, 120, 6A; A-047-A-049
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Effect of Additive Element on the Properties of Mechanically Alloyed Fe-Y2O3 Alloys
    Autorzy:
    Ahn, J.-H.
    Kim, T. K.
    Ahn, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/356561.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    mechanical alloying
    ODS alloy
    nanoparticles
    oxide dispersion strengthening
    high-energy ball milling
    Opis:
    In the present work, we have examined the effect of Ti on the properties of Fe-Y2O3 alloys. The result showed that the addition of Ti was effective for improving mechanical properties. This is due to the reduction of oxides by Ti during mechanical alloying and hot-consolidation. In particular, iron oxides are effectively reduced by the addition of Ti. Compared to the pristine Fe-Y2O3 alloys, titanium-added alloys exhibited fine and uniform microstructures, resulting in at least 60% higher tensile strength.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1043-1046
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Synthesis And Electrochemical Characteristics Of Mechanically Alloyed Anode Materials SnS2 For Li/SnS2 Cells
    Synteza mechaniczna i charakterystyka elektrochemiczna materiałów anodowych SnS2 dla ogniw Li/SnS2
    Autorzy:
    Hong, J. H.
    Liu, X. J.
    Park, D. K.
    Kim, K. W.
    Ahn, H. J.
    Ahn, I. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/356903.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    MA
    Li/SnS2 cell
    PCA
    wet milling process and electrochemical characteristics
    ogniwa Li/SnS2
    charakterystyka elektromechaniczna
    Opis:
    With the increasing demand for efficient and economic energy storage, tin disulfide (SnS2), as one of the most attractive anode candidates for the next generation high-energy rechargeable Li-ion battery, have been paid more and more attention because of its high theoretical energy density and cost effectiveness. In this study, a new, simple and effective process, mechanical alloying (MA), has been developed for preparing fine anode material tin disulfides, in which ammonium chloride (AC), referred to as process control agents (PCAs), were used to prevent excessive cold-welding and accelerate the synthesis rates to some extent. Meanwhile, in order to decrease the mean size of SnS2 powder particles and improve the contact areas between the active materials, wet milling process was also conducted with normal hexane (NH) as a solvent PCA. The prepared powders were both characterized by X-ray diffraction, Field emission-scanning electron microscopeand particle size analyzer. Finally, electrochemical measurements for Li/SnS2 cells were takenat room temperature, using a two-electrode cell assembled in an argon-filled glove box and the electrolyte of 1M LiPF6 in a mixture of ethylene carbonate(EC)/dimethylcarbonate (DMC)/ethylene methyl carbonate (EMC) (volume ratio of 1:1:1).
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1191-1194
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Similarity of chromosome structure among Populus tremula var. davidiana, Populus alba and their hybrids revealed by FISH karyotype analysis
    Autorzy:
    Kim, Y.G.
    Kwon, S.H.
    Kang, H.I.
    Yoem, D.B.
    Kim, K.W.
    Kim, H.H.
    Kang, K.S.
    Powiązania:
    https://bibliotekanauki.pl/articles/2077655.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Instytut Dendrologii PAN
    Tematy:
    Karyotype analysis
    Fluorescence in situ hybridization
    Ribosomal DNA site
    Poplar
    Cytogenetics
    Opis:
    The genus Populus is one of the important tree species in Korean peninsula and many other coun- tries in the world. It represents the model species of forest genomics because it grows fast and reproduces rapidly. In this reason, their genetic characteristics have been well studied and the whole genome has been sequenced completely in some species. However, cytogenetic study of the genus Populus has been limited. In the present study, karyotypes of Korean aspen (P. tremula var. davidiana), Silver poplar (P. alba) and their two hybrids, Suwon aspen (P. tremula var. glandulosa) and Hyun aspen (P. alba × P. tremula var. glandulsa) were analyzed by means of the fluorescence in situ hybridization (FISH). Root samples were collected from mature trees in the demonstration forest, located at Suwon, Kyonggi province in South Korea. The fresh root cells were examined by DAPI (4’,6-diamidino-2-phenylindole) staining and FISH using 45S rDNA and 5S rDNA probes. As the results, the chromosome compositions of all species were the same as 2n = 38. The karyotype formulas of Korean aspen, Silver poplar, Suwon aspen and Hyun aspen were 28m + 6sm + 4st (2sat), 26m + 10sm (2sat) + 2st, 26m + 12sm (2sat) and 28m + 10sm (2sat), respectively. The four species had one pair of 45S rDNA site and one pair of 5S rDNA site in common with FISH karyotypes. The similarity of FISH karyotypes among four species indicated close genetic relationship and coexistence of their interspecific hybrids. This research will provide genetic information on cytogenetic research of Populus and genetic mapping that can be applied to the breeding program of Populus in the near future.
    Źródło:
    Dendrobiology; 2020, 83; 68-74
    1641-1307
    Pojawia się w:
    Dendrobiology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Formation And Stabilization Of Silver Nanoparticles In Ethanol By Phosphinic Acid
    Redukcja i stabilizacja nanocząstek srebra w etanolu przez kwas fosforowy
    Autorzy:
    Kim, J.-K.
    Shim, H.-M.
    Park, M. J.
    Koo, K.-K.
    Powiązania:
    https://bibliotekanauki.pl/articles/356073.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    silver
    nanoparticle
    kinetic analysis
    phosphinic acid
    reduction
    srebro
    nanocząstki
    analiza kinetyczna
    kwas fosforowy
    redukcja
    Opis:
    Although phosphinic acid (H3PO2) has a powerful reduction potential, the reduction of silver ions by phosphinic acid salt has not yet been reported. In this work, colloidal silver has successfully synthesized by reducing silver ions in ethanol with phosphinic acid as a reducing agent. The effects of [AgNO3]/[H3PO2] ratios and reaction temperature were considered. Spherical silver nanoparticles with cubic structure were successfully prepared and their diameters were measured to be 8.5±0.9 nm − 11.3±0.2 nm. Half-life analysis showed that the reduction of silver ions proceeded with the reaction order of 1.30 on concentration of phosphinic acid and activation energy of 120.7 kJ/mol.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1293-1296
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Heat Treatment on the Microstructure and Tensile Deformation Behavior of Oxide Dispersion Strengthened Alloys Manufactured by Complex Milling Process
    Autorzy:
    Kim, Y.-K.
    Kim, J.-H.
    Gwon, J.-H.
    Lee, K.-A.
    Powiązania:
    https://bibliotekanauki.pl/articles/352535.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ball milling
    oxide dispersion strengthening
    microstructure
    tensile deformation behavior
    Opis:
    This study attempted to manufacture an ODS alloy by combining multiple milling processes in mechanical alloying stage to achieve high strength and fracture elongation. The complex milling process of this study conducted planetary ball milling, cryogenic ball milling and drum ball milling in sequential order, and then the microstructure and tensile deformation behavior were investigated after additional heat treatment. The oxide particles distributed within the microstructure were fine oxide particles of 5~20 nm and coarse oxide particles of 100~200 nm, and the oxide particles were confirmed to be composed of Cr, Ti, Y and O. Results of tensile tests at room temperature measured yield strength, tensile strength and elongation as 1320 MPa, 2245 MPa and 4.2%, respectively, before heat treatment, and 1161 MPa, 2020 MPa and 5.5% after heat treatment. This results indicate that the ODS alloy of this study gained very high strengths compared to other known ODS alloys, allowing greater plastic zones.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1335-1340
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Manufacturing And High Temperature Oxidation Properties Of Electro-Sprayed Fe-24.5% Cr-5%Al Powder Porous Metal
    Wytwarzanie i wysokotemperaturowe utlenianie elektro-rozpylanego porowatego proszku Fe-24.5% Cr-5%Al
    Autorzy:
    Lee, K-A.
    Oh, J-S.
    Kong, Y-M.
    Kim, B-K.
    Powiązania:
    https://bibliotekanauki.pl/articles/350912.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    powder porous metal
    electro-spray process
    electric wire explosion
    Fe-24Cr-5Al
    high temperature oxidation
    porowaty proszek metalu
    elektrorozpylanie
    utlenianie wysokotemperaturowe
    Opis:
    Fe-Cr-Al based Powder porous metals were manufactured using a new electro-spray process, and the microstructures and high-temperature oxidation properties were examined. The porous materials were obtained at different sintering temperatures (1350°C, 1400°C, 1450°C, and 1500°C and with different pore sizes (500 μm, 450 μm, and 200 μm). High-temperature oxidation experiments (TGA, Thermal Gravimetry Analysis) were conducted for 24 hours at 1000°C in a 79% N2+ 21% O2, 100 mL/min. atmosphere. The Fe-Cr-Al powder porous metals manufactured through the electro-spray process showed more-excellent oxidation resistance as sintering temperature and pore size increased. In addition, the fact that the densities and surface areas of the abovementioned powder porous metals had the largest effects on the metal’s oxidation properties could be identified.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1169-1173
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Study On Dispersion Stability Of Nickel Nanoparticles Synthesized By Wire Explosion In Liquid Media
    Badanie stabilności dyspersji nanocząstek niklu wytworzonych metodą WEP w ciekłym medium
    Autorzy:
    Kim, C. K.
    Lee, G.-J.
    Lee, M. K.
    Rhee, C. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/356909.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    nickel nanofluid
    pulsed wire evaporation
    surfactant
    zeta potential
    dispersion stability
    nanocząstka niklu
    środek powierzchniowo czynny
    stabilność dyspersji
    potencjał zeta
    dyspersja
    Opis:
    In this study, nickel nanoparticles were synthesized in ethanol using portable pulsed wire evaporation, which is a one-step physical method. From transmission electron microscopy images, it was found that the Ni nanoparticles exhibited a spherical shape with an average diameter of 7.3 nm. To prevent aggregation of the nickel nanoparticles, a polymer surfactant was added into the ethanol before the synthesis of nickel nanoparticles, and adsorbed on the freshly synthesized nickel nanoparticles during the wire explosion. The dispersion stability of the prepared nickel nanofluids was investigated by zeta-potential analyzer and Turbiscan optical analyzer. As a result, the optimum concentration of polymer surfactant to be added was suggested for the maximized dispersion stability of the nickel nanofluids.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1379-1382
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis and Optimization of Micro Speaker-Box Using a Passive Radiator in Portable Device
    Autorzy:
    Jiang, Y.-W.
    Kwon, J.-H.
    Kim, H.-K.
    Hwang, S.-M.
    Powiązania:
    https://bibliotekanauki.pl/articles/176530.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    passive radiator
    speaker box
    SPL improvement
    Sound Pressure Level
    Opis:
    With the rapid development of multimedia devices such as smart phones and tablet PCs, microspeakers have been recently increasingly used for audio equipment. Improving the acoustic performance of a microspeaker is always a main concern, especially in the low frequency range. To avoid sound cancelation, a microspeaker unit is usually inserted into a speaker box. A passive radiator is also used in speaker boxes to improve the sound performance in the loudspeaker system. However, passive radiators have not been applied into microspeaker system. In this study, a speaker box with a passive radiator was analyzed and optimized to achieve a higher Sound Pressure Level (SPL) in a microspeaker system. The Finite Element Method (FEM), two-degree-of-freedom (DOF) vibration theory, and a plane circular piston sound source were used to study the electromagnetic, vibration, and acoustic characteristics, respectively. Optimization was conducted by changing the mass, stiffness, and size of the passive radiator. Based on the optimized parameters, a new sample was manufactured. The experiment results show that the SPL of the optimized speaker box with a passive radiator is improved by 5 dB at 200 Hz compared with the one without a radiator. The analysis results also matched the experiment results.
    Źródło:
    Archives of Acoustics; 2017, 42, 4; 753-760
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Oligonol prevented the relapse of dextran sulfate sodium-ulcerative colitis through enhancing Nrf2-mediated antioxidative defense mechanism
    Autorzy:
    Kim, K.-J.
    Park, J.-M.
    Lee, J.-S.
    Kim, Y.S.
    Kangwan, N.
    Han, Y.-M.
    Kang, E.A.
    An, J.M.
    Park, Y.K.
    Hahm, K.-B.
    Powiązania:
    https://bibliotekanauki.pl/articles/69501.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Fizjologiczne
    Tematy:
    ulcerative colitis
    inflammatory bowel disease
    oxidative stress
    oligonol
    polyphenol
    adaptive response
    quinone oxidoreductase
    relapse
    nuclear factor-kappaB
    tumour necrosis factor-alpha
    Źródło:
    Journal of Physiology and Pharmacology; 2018, 69, 3
    0867-5910
    Pojawia się w:
    Journal of Physiology and Pharmacology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Development of Ship Watch Keeping Supporting Aids
    Autorzy:
    Im, N.
    Kim, E. K.
    Han, S. H.
    Jeong, J. S.
    Lee, S. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/117602.pdf
    Data publikacji:
    2013
    Wydawca:
    Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
    Tematy:
    Ship Watchkeeping
    Deck Officers
    Navigation Visual Supporting System
    Intelligent Technology
    Dangerous Floating Objects
    Binocular Telescope
    laser distance measuring unit
    Sea Trial Test
    Opis:
    This study deals with the development of ship watch keeping supporting aids that will be useful for ship deck officers in recognizing navigational harmful obstacles such as sea marks and small floating objects on the sea. The developed watch keeping supporting aids is made up of four components; a composite video sensor to produce video signal, a laser distance measuring part, a Pan/Tilt part and a central control part. The system was installed in a ship in order to verify its performance of the recognition ability on the sea. The comparison was made between the recognition ability of the system and that of watch keeping deck officers’. The image from the watch keeping supporting system was found to be more recognizable than that of a binocular telescope within a 5 km distance. The newly suggested system is expected to be used to recognize small dangerous floating objects more easily when navigation deck officers have a duty of watch keeping for navigation especially near harbor area.
    Źródło:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2013, 7, 4; 501-506
    2083-6473
    2083-6481
    Pojawia się w:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Formation of Tungsten/Ammonium Perchlorate Composites and Their Reaction Kinetics
    Autorzy:
    Shim, H.-M.
    Lee, E.-A.
    Kim, J.-K.
    Kim, H.-S.
    Koo, K.-K.
    Powiązania:
    https://bibliotekanauki.pl/articles/358373.pdf
    Data publikacji:
    2015
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
    Tematy:
    ammonium perchlorate
    composite
    thermal decomposition
    Opis:
    The reaction kinetics of tungsten nanoparticles/ammonium perchlorate (W/AP) composites, produced by a spray drying technique, were analyzed and compared with those of neat AP particles and aluminum nanoparticles/AP (Al/AP) composites. The W was found to raise the onset temperature of the thermal decomposition of AP by increasing the activation energy, whereas Al conversely lowered the onset temperature of AP due to the decreased activation energy. From the master plots of kinetic models with the experimental data, the Prout-Tompkins model and the 1-D diffusion controlled model were found to describe the low-temperature decomposition (LTD) and high-temperature decomposition (HTD), respectively, giving remarkable agreement with experimental curves for all heating rates. The presence of W was found to increase the HTD zone width compared with that of neat AP particles and Al/AP composites. Analysis of the average activation energy and pre-exponential factor showed that W increases the energy barrier and the frequency of occurrence of the reaction compared with that of neat AP particles at the LTD state, whereas W decreases both of them at the HTD state. The effect of Al was also shown to be similar to that of W, but the magnitudes of the variation in activation energy and the pre-exponential factor were relatively small.
    Źródło:
    Central European Journal of Energetic Materials; 2015, 12, 4; 703-722
    1733-7178
    Pojawia się w:
    Central European Journal of Energetic Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Combined Effect of Zr and Si on Isothermal Oxidation of Ti
    Autorzy:
    Ha, S.-H.
    Kim, B.-H.
    Yoon, Y.-O.
    Lim, H.-K.
    Kim, S. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/353260.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ti
    Zr
    Si
    silicide
    oxidation
    Opis:
    In this study, the combined effect of Zr and Si on isothermal oxidation of Ti for 25 and 50h at 820°C, which is the temperature related to exhaust valves operation, was investigated. Si addition into Ti-5mass%Zr alloy led to a distribution of silicide Ti5Si3 phase formed by a eutectic reaction. The Ti sample containing only Zr showed more retarded oxidation rate than Ti-6Al-4V, the most prevalent Ti alloy, at the same condition. However, while a simultaneous addition of Zr and Si resulted in greater increase of oxidation resistance. The oxide layer formed after the addition of Zr and Si comprised TiO2, ZrO2, and SiO2.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1493-1495
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Heat Treatment on Microstructure and Impact Toughness of Ti-6Al-4V Manufactured by Selective Laser Melting Process
    Autorzy:
    Lee, K.-A.
    Kim, Y.-K.
    Yu, J.-H.
    Park, S.-H.
    Kim, M.-C.
    Powiązania:
    https://bibliotekanauki.pl/articles/354570.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    selective laser melting
    Ti-6Al-4V
    microstructure
    impact toughness
    heat treatment
    Opis:
    This study manufactured Ti-6Al-4V alloy using one of the powder bed fusion 3D-printing processes, selective laser melting, and investigated the effect of heat treatment (650°C/3hrs) on microstructure and impact toughness of the material. Initial microstructural observation identified prior-β grain along the building direction before and after heat treatment. In addition, the material formed a fully martensite structure before heat treatment, and after heat treatment, α and β phase were formed simultaneously. Charpy impact tests were conducted. The average impact energy measured as 6.0 J before heat treatment, and after heat treatment, the average impact energy increased by approximately 20% to 7.3 J. Fracture surface observation after the impact test showed that both alloys had brittle characteristics on macro levels, but showed ductile fracture characteristics and dimples at micro levels.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1341-1346
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characteristics Of The Porous Body Sintered By Nano-Sized Fe-Cr-Al Alloy Powder
    Charakterystyka porowatego korpusu spiekanego z nanometrycznego proszku stopu Fe-Cr-Al
    Autorzy:
    Lee, S.-I.
    Lee, S.-H.
    Gu, B.-U.
    Lee, D.-W.
    Kim, B.-K.
    Powiązania:
    https://bibliotekanauki.pl/articles/356635.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Fe-Cr-Al powder
    metallic sponges
    sintering temperature
    oxidation resistance
    proszek Fe-Cr-Al
    proszek nanometryczny
    temperatura spiekania
    odporność na utlenianie
    Opis:
    Porous metal with uniform honeycomb structure was successfully produced by sintering using Fe-Cr-Al nano powder, which was prepared by the pulsed wire evaporation (PWE) in ethanol. Its process consisted of the several steps; 1) coating on the surface of polyurethane sponge with the liquid droplets generated from the ethanol-based slurry where the Fe-Cr-Al nano powders were uniformly dispersed, 2) heat treatment of debinding to remove the polyurethane sponge and 3) sintering of the porous green body formed by Fe-Cr-Al nano powders. The strut thickness of porous Fe-Cr-Al was increased by the increase of spraying times in ESP step. Also, The shrinkages and the oxidation resistance of the sintered porous body was increased with increase of sintering temperature. The optimal sintering temperature was shown to 1450°C in views to maximize the oxidation resistance and sinterability.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1275-1279
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Oxidation Behavior of Steel with Cr Content and Water Flow Rate
    Autorzy:
    Kim, D.-J.
    Kim, K. M.
    Shin, J. H.
    Cheong, Y. M.
    Lee, E. H.
    Lee, G. G.
    Kim, S. W.
    Kim, H. P.
    Choi, M. J.
    Lim, Y. S.
    Hwang, S. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/351548.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    steel
    flow accelerated corrosion
    Cr content
    flow rate
    surface oxides
    Opis:
    Fast water flow facilitates ferrous ion transport leading to flow accelerated corrosion (FAC) of carbon steel and the possibility of a large accident through a failure of a secondary pipe in a nuclear power plant. Ion transport is directly linked to oxide properties such as the thickness, chemical composition and porosity. This work deals with a precise observation of the cross section of the corroded specimen focusing on an oxide passivity and its thickness using SEM (scanning electron microscope) and TEM (transmission electron microscope) as well as an apparent weight loss and a surface observation for the specimens corroded using a rotating cylindrical electrode autoclave system in pure water of pH 7 at 150°C having dissolved oxygen below 1 ppb within a flow rate range of 0 to 10 m/s. The Cr content in steel was changed from 0.02 to 2.4 wt%. Increasing the Cr content in the alloy, the FAC rate and oxide thickness decreased. The oxide porosity tends to decrease with the Cr content and immersion time owing to the development of Cr containing oxide. The oxidation behavior is not changed with the immersion time.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1383-1387
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Cu Addition on Oxide Growth of Al-7 mass%Mg Alloy at High Temperature
    Autorzy:
    Ha, Seong-Ho
    Shah, Abdul Wahid
    Kim, Bong-Hwan
    Yoon, Young-Ok
    Lim, Hyun-Kyu
    Kim, Shae K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2049221.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    Cu addition
    oxidation
    phase diagram
    Opis:
    Effect of Cu addition on oxide growth of Al-7 mass%Mg alloy at high temperature was investigated. As-cast microstructures of Al-7 mass%Mg and Al-7 mass%Mg-1 mass%Cu alloys showed α-Al dendrites and area of secondary particles. The 1 mass%Cu addition into Al-7 mass%Mg alloy formed Mg32(Al, Cu)49 ternary phase with β-Al3Mg2. The total fraction of two Mg-containing phases in Cu-added alloy was higher than the β-Al3Mg2 fraction in Cu-free alloy. From measured weight gains depending on time at 500°C under an air atmosphere, it was shown that all samples exhibited significant weight gains depending on time. Al-7mass%Mg1mass%Cu alloy showed the relatively increased oxidation rate when compared with Cu-free alloy. All the oxidized cross-sections throughout the entire oxidation time showed coarse and dark areas regarded as oxides grown from the surface to inside, but bigger oxidized areas were formed in the Al-7mass%Mg-1mass%Cu alloy containing higher fraction of Mg-based phases in the as-cast microstructure. As a result of compositional analysis on the oxide clusters, it was found that the oxide clusters contained Mg-based oxides formed through internal oxidation during a long time exposure to oxidizing environments.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 3; 699-702
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of Si Addition on Oxide Growth of Al-6 mass%Mg Alloy Melts
    Autorzy:
    Yoon, Young-Ok
    Ha, Seong-Ho
    Shah, Abdul Wahid
    Kim, Bong-Hwan
    Lim, Hyun-Kyu
    Kim, Shae K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2049203.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    Si addition
    oxidation
    phase diagram
    Opis:
    Influence of Si addition on oxide layer growth of Al-6 mass%Mg alloys in molten state was investigated in this study. After melt holding for 24 h, the melt surface of only Si-free alloy became significantly bumpy, while no considerably oxidized surface was observed even with 1 mass%Si addition. There was no visible change on the appearance of melt surfaces with increasing Si content. As a result of compositional analysis on the melt samples between before and after melt holding, the Si-added alloys nearly maintained their Mg contents even after the melt holding for 24 h. On the other hand, the Mg content in the Si-free alloy showed a great reduction. The bumpy surface on Si-free alloy melt showed a large amount of pores and oxide clusters in its cross-section, while the Si-added alloy had no significantly grown oxide clusters on the surfaces. As a result of compositional analysis on the surfaces, the oxide clusters in Si-free alloy contained a great amount of Mg and oxygen. The oxide layer on the Si-added alloy was divided into Mg-rich and Mg-poor areas and contained certain amounts of Si. Such a mixed oxide layer containing Si would act as a protective layer during the melt holding for a long duration.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 3; 695-698
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect Of Carbon Nanotubes On The Properties Of Spark Plasma Sintered ZrO2/CNT Composites
    Wpływ nanorurek węglowych na właściwości spiekanych metodą sps kompozytów ZrO2/CNT
    Autorzy:
    Shim, D. H.
    Jung, S. S.
    Kim, H. S.
    Cho, H.
    Kim, J. K.
    Kim, T. G.
    Yoon, S. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/351266.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    CNT
    ZrO2
    composite
    SPS
    kompozyty
    Opis:
    Zirconia matrix ZrO2/CNT composite materials reinforced with multiwall carbon nanotubes were fabricated using a spark plasma sintering technique. The effects of the amount of CNTs addition, sintering temperature and sintering pressure on the properties of the resulting ZrO2/CNT composites were examined. 0 to 9 vol. % CNTs were dispersed in zirconia powder, and the resulting mixture was sintered. The electrical conductivity, hardness, flexural strength, and density were measured to characterize the composites. The friction and wear properties of the composites were also tested. The flexural strength and friction coefficient of the composites were improved with up to 6 vol.% of CNT addition and the flexural strength showed a close relationship with the relative density of the composite. The electrical conductivity increased with increasing proportion of the CNTs, but the efficiency was reduced at more than 6 vol.% CNTs.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1315-1318
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure Formation of Al-5 mass%Mg Alloy Melts by Interaction with Silica
    Autorzy:
    Kim, Sun-Ki
    Ha, Seong-Ho
    Kim, Bong-Hwan
    Yoon, Young-Ok
    Lim, Hyun-Kyu
    Kim, Shae K.
    Kim, Yong-Jig
    Powiązania:
    https://bibliotekanauki.pl/articles/2049152.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    silica
    reduction
    Mg2Si
    phase diagram
    Opis:
    Dissolution of Si in Al-5 mass%Mg alloy melt by the reduction of SiO2 and its effect on microstructure formation of the alloy after solidification were investigated. Al-5 mass%Mg alloy without silica powder had approximately 0.05 mass%Si as an impurity. No significant difference in Si content was observed after the reaction with silica for 10 min, while the Si content increased up to about 0.12 mass% after 30 min. From the microstructure analysis and calculation of Scheil-Gulliver cooling, it was considered that as-cast microstructures of Al-5 mass%Mg-1 mass% SiO2 alloys had the distribution of eutectic phase particles, which are comprised of β-Al3Mg2 and Mg2Si phases. Based on the phase diagrams, only limited amount of Mg can be selectively removed by silica depending on the ratio of Si and Mg. Addition of silica of more than approximately 1.5 mass% in Al-5 mass%Mg alloy led to the formation of spinel and removal of both mg and Al from the melt.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 4; 947-950
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization of Ca Precipitation in Al-Mg Alloys Containing a Trace of Ca During Homogenization
    Autorzy:
    Ha, Seong-Ho
    Shin, Young-Chul
    Kim, Bong-Hwan
    Yoon, Young-Ok
    Lim, Hyun-Kyu
    Lim, Sung-Hwan
    Kim, Shae K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2049165.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    precipitation
    Mg+Al2Ca mater alloy
    transmission electron microscope
    phase diagram
    Opis:
    In this study, precipitation of Ca in Al-Mg alloys containing a trace of Ca during homogenization was investigated using a transmission electron microscope (TEM) and calculated phase diagrams. TEM result indicated that the Ca-based particles found in the examined sample are Ca7Mg7.5Si14. From the calculation of Scheil-Gulliver cooling, it was found that the Ca was formed as Al4Ca and C36 laves phases with Mg2Si and Al13Fe4 from other impurities phase during solidification. No Ca-Mg-Si ternary phase existed at the homogenization temperature in the calculated phase diagram. From the phase diagram of Al-Al4Ca-Mg2Si three-phase isothermal at 490°C, it was shown that Ca7Mg6Si14 phase co-exists with Al, Mg2Si and Al4Ca in the largest region and with only Al and Mg2Si in Al4Ca-poor regions. It was thought that the Ca7Mg6Si14 ternary phase was formed by the interaction between Mg2Si and Al4Ca considering that the segregation can occur throughout the entire microstructures.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 4; 959-962
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Study On The Metal Carbide Composite Diffusion Bonding For Mechanical Seal
    Badanie łączenia dyfuzyjnego kompozytu metal węglik na mechaniczne uszczelnienie
    Autorzy:
    Kim, D.-K.
    Shon, I.-J.
    Song, J.
    Ryu, W.-J.
    Shin, H.-Ch.
    Kwon, E.-Y.
    Shin, H.
    Kang, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/356399.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    diffusion bonding
    nanostructures
    mechanical seal
    hard metal
    mechanical properties
    łączenie
    nanostruktura
    uszczelnienie mechaniczne
    twardy metal
    właściwości mechaniczne
    Opis:
    Mechanical Seal use highly efficient alternative water having a great quantity of an aqueous solution and has an advantage no corrosion brine. Metal Carbide composites have been investigated as potential materials for high temperature structural applications and for application in the processing industry. The existing Mechanical seal material is a highly expensive carbide alloy, and it is difficult to take a price advantage. Therefore the study of replacing body area with inexpensive steel material excluding O-ring and contact area which demands high characteristics is needed. The development of WC-Ni base carbide alloy optimal bonding composition technique was accomplished in this study. To check out the influence of bonding temperature and time, bonding characteristics of sintering temperature was experimented. The bonding statuses of this test specimen were excellent. The hardness of specimen and bonding rate were measured using ultrasound equipment. In this work, Powder of WC (involved VC, Cr), Co and Mo2C mixed by attrition milling for 24hours. Nanostructured WC-27.6wt.%Ni-1.5wt.%Si-0.11wt.%VC-1.1wt.%B4C composite were fabricated at 1190°C by high temperature vacuum furnace. To check out the influence of bonding temperature and time, bonding characteristics of sintering temperature was experimented. Its relative density was about 99.7%. The mechanical properties (hardness and fracture toughness) were 87.2 HRA and 4.2 M·Pam1/2, respectively. The bonding status of this test specimen was excellent and the thickness of bonding layer was 20 ~30§ at 1050 and 1060°C bonding temperature.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1479-1483
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Structural and Optical Properties of Hydrothermally Synthesized ZnO and $Zn_{0.99}O:Eu^{3+}$ Powders
    Autorzy:
    Park, K.
    Hakeem, D.
    Kim, J.
    Kim, Y.
    Kim, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1398243.pdf
    Data publikacji:
    2018-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    78.55.-m
    78.55.Hx
    78.55.Et
    Opis:
    The structural and optical properties of the ZnO and $Zn_{0.99}O:Eu^{3+}$ powders synthesized by the hydrothermal method at two different temperatures (150°C and 250°C) were studied. The ZnO and $Zn_{0.99}O:0.01Eu^{3+}$ powders synthesized at 150 and 250°C showed rod- and flower-like morphologies, respectively. The as-synthesized and annealed ZnO and $Zn_{0.99}O:0.01Eu^{3+}$ powders formed the wurtzite crystal structure and P6₃mc space group. The crystallite size of the as-synthesized and annealed ZnO powders increased by the incorporation of $Eu^{3+}. The photoluminescence properties of annealed $Zn_{0.99}O:0.01Eu^{3+}$ powders were substantially improved by controlling the synthesis temperature. The annealed $Zn_{0.99}O:0.01Eu^{3+}$ powders synthesized at 250°C displayed much stronger emission intensity than those at 150°C.
    Źródło:
    Acta Physica Polonica A; 2018, 133, 4; 902-906
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Growth and Characterization of Indium-Doped Zinc Oxide Thin Films Prepared by Sol-Gel Method
    Autorzy:
    Kim, M.
    Yim, K.
    Kim, S.
    Nam, G.
    Lee, D.
    Kim, Jin
    Kim, Jong
    Leem, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1491351.pdf
    Data publikacji:
    2012-01
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.05.Dz
    81.20.Fw
    78.66.Hf
    Opis:
    Indium-doped ZnO thin films were deposited by sol-gel spin-coating method with various In content. The effects of In content on the structural and optical properties of the indium-doped ZnO thin films were investigated by scanning electron microscopy, X-ray diffraction, and UV-visible spectroscopy. The particle-like surface morphology and the crystallinity of the indium-doped ZnO thin films were affected by change in the In content, especially at the In content of 3 at.%. The values of direct band gap were decreased with increase in the In content. The width of localized states in the optical band gap of the indium-doped ZnO thin films were changed with In content and the Urbach energy $(E_{U})$ was changed inversely with optical band gap of the indium-doped ZnO thin films.
    Źródło:
    Acta Physica Polonica A; 2012, 121, 1; 217-220
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of Fe-TiB2 Nanocomposites by Spark-Plasma Sintering of a (FeB, TiH2) Powder Mixture
    Autorzy:
    Huynh, X.-K.
    Kim, B.-W.
    Kim, J.-S.
    Powiązania:
    https://bibliotekanauki.pl/articles/351368.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Fe-TiB2 nanocomposite
    mechanical activation
    spark plasma sintering
    self-propagating high-temperature synthesis reaction
    Opis:
    Fe-40wt% TiB2 nanocomposites were fabricated by mechanical activation and spark-plasma sintering of a powder mixture of iron boride (FeB) and titanium hydride (TiH2). The powder mixture of (FeB, TiH2) was prepared by high-energy ball milling in a planetary ball mill at 700 rpm for 3 h followed by spark-plasma sintering (SPS) at various conditions. Analysis of the change in relative sintered density and densification rate during sintering showed that a self-propagating high-temperature synthesis reaction occurs to form TiB2 from FeB and Ti. A sintered body with relative density higher than 98% was obtained after sintering at 1150°C for 5 and 15 min. The microstructural observation of sintered compacts with the use of FE-SEM and TEM revealed that ultrafine particulates with approximately 5 nm were evenly distributed in an Fe-matrix. A hardness value of 83 HRC was obtained, which is equivalent to that of conventional WC-20 Co systems.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 1043-1047
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Mechanical Activation on the in situ Formation of TiB2 Particulates in the Powder Mixture of TiH2 and FeB
    Autorzy:
    Huynh, X.-K.
    Kim, B.-W.
    Kim, J. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/355844.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    mechanical activation
    in situ formation
    TiB2 particulate
    Fe-matrix
    specific ball-milling energy
    Opis:
    The in situ formation of TiB2 particulates via an interface reaction between Ti and FeB powders was studied. The effects of mechanical activation by high-energy milling on the decomposition of TiH2 and the interface reactions between Ti and FeB powders to form TiB2 were investigated. Powder mixtures were fabricated using planetary ball-milling under various milling conditions. The specific ball-milling energy was calculated from the measured electrical power consumption during milling process. High specific milling energy (152.6 kJ/g) resulted in a size reduction and homogeneous dispersion of constituent powders. This resulted in a decrease in the decomposition temperature of TiH2 and an increase in the formation reaction of TiB2 particulates in the Fe matrix, resulting in a homogeneous microstructure of nanoscale TiB2 evenly distributed within the Fe matrix. In contrast, the powder mixture milled with low specific milling energy (36.5 kJ/g) showed an inhomogeneous microstructure composed of relatively large Fe-Fe2 B particles surrounded by a thin layer of Fe-TiB2 within a finely dispersed Fe-TiB2 matrix region.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1393-1398
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Investigation of an odor source in Changwon City using multi-monitoring methods. A case study of Korea
    Autorzy:
    Prueksakorn, K.
    Kim, T.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/207109.pdf
    Data publikacji:
    2015
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    odor
    industrial plants
    industrial city
    odor measurements
    odor nuisance
    odor pollutants
    odorimetry
    Changwon City
    zapach
    zakłady przemysłowe
    miasto przemysłowe
    pomiary zapachu
    uciążliwość zapachowa
    badanie zapachu
    emisja substancji zapachowych
    jakość zapachowa powietrza
    metody pomiarowe uciążliwości zapachowych
    ocena uciążliwości zapachu
    Changwon
    Opis:
    It is a regular occurrence for residents living near industrial plants to complain regarding odor problems. Those plants may also try to protect themselves from liability by demonstrating some environmental evidence. An investigation to prove whether the accused industrial complex is the major source of released odors among several potential sources of odor problems was carried out using the combination of measurement techniques. The multi-monitoring methods comprise utilizations of olfactory system, questionnaire, electronic detector and chemical analysis. This study demonstrated the achievement of integrating scientific monitoring methods to support the enforcement of odor acts for management in the industrial city.
    Źródło:
    Environment Protection Engineering; 2015, 41, 4; 109-130
    0324-8828
    Pojawia się w:
    Environment Protection Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    ZnO Nanorods on Nanofibrous ZnO Seed Layers by Hydrothermal Method and Their Annealing Effects
    Autorzy:
    Yim, K.
    Jeon, S.
    Kim, M.
    Kim, S.
    Nam, G.
    Lee, D.
    Kim, Jin
    Kim, Jong
    Leem, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1491348.pdf
    Data publikacji:
    2012-01
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.05.Dz
    81.15.Lm
    78.55.Et
    Opis:
    ZnO nanorods were grown by using the hydrothermal method on p-type Si (100) substrates with nanofibrous ZnO seed layers. Before the ZnO nanorods growth, nanofibrous ZnO seed layers were spin-coated onto the Si substrates. The structural and optical properties of ZnO nanorods were characterized by scanning electron microscopy, X-ray diffraction, and photoluminescence. The fibrous ZnO nanorods is possible due to the surface morphology of the nanofibrous ZnO seed layers. To investigate annealing effects of the ZnO nanorods, the post-annealing process was carried out at various temperatures ranging from 300 to 700C under argon conditions. The structural and optical properties of the ZnO nanorods were also affected by the post-annealing treatment.
    Źródło:
    Acta Physica Polonica A; 2012, 121, 1; 214-216
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of checklists for agricultural safety management
    Autorzy:
    Kim, H.
    Rasanen, K.
    Chae, H.
    Lee, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2081898.pdf
    Data publikacji:
    2018
    Wydawca:
    Instytut Medycyny Wsi
    Tematy:
    checklist
    agriculture
    safety
    management
    Opis:
    Introduction. The current health and safety management system under the Occupational Health and Safety Act has avoided agriculture in Korea. It is important to consider the various safety systems used in agricultural health and safety to develop effective regulations. Objective. The aims were to classify and review the items from various checklists using safety systems, such as design, training, etc., ultimately aimed at proposing directions for improving the health and safety of farmers. Materials and method. Among the retrieved checklists with Google, four were chosen for this study, based on criteria such as the Checklist developed by an international organization, as well as others. Each item on the checklist was categorized using criteria concerning safety systems, developed based on previous studies. Results. The total number of analyzed items was 573, which is 36 more than the actual number of checklist items (537). The proportion of items belonging to the training/procedures system was the highest (32.5%); the second-highest was for the mitigation system – 18.2%.; the third-largest proportion of items was maintenance/inspection – with 14.3%. Items related to the design and human factor systems were 8.2% and 5.6%, respectively. The safety system with the lowest proportion was the warning/notification system – 4.2% of the total items. The proportion of items that could not be classified into safety systems was found to be 16.1%. Conclusions. A large number of items belonging to the training/procedures system reported as occasionally not effective in prevention of injury were found in the checklists. It appears important to develop checklist items proposing the supplementation of various safety systems, rather than presenting items that are biased towards certain safety systems.
    Źródło:
    Annals of Agricultural and Environmental Medicine; 2018, 25, 3; 494-499
    1232-1966
    Pojawia się w:
    Annals of Agricultural and Environmental Medicine
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication and Characterization of GaN/Polymer Composite p-n Junction with PEDOT Nanoparticle Interface Layer
    Autorzy:
    Kim, M.
    Jin, S.
    Choi, H.
    Kim, G.
    Yim, K.
    Kim, S.
    Nam, G.
    Yoon, H.
    Kim, Y.
    Lee, D.
    Kim, Jin
    Kim, Jong
    Leem, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1505152.pdf
    Data publikacji:
    2011-06
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    73.61.Ey
    81.15.Gh
    Opis:
    A heavily Si-doped GaN/polymer hybrid structure with p-type poly(3,4-ethylene-dioxythiophene):beta-1,3-glucan (PEDOT nanoparticle) interface layer has been fabricated. The Si-doped GaN thin film with carrier concentration of 1 × $10^{19} cm^{-3}$ was grown by metal-organic chemical vapor deposition. The PEDOT nanoparticle with various sizes ranging from 60 to 120 nm was synthesized via a miniemulsion polymerization process. The electrical conductivity of the PEDOT nanoparticle is less than 1.2 S/cm. The current-voltage (I-V) characteristic of the hybrid structure shows diode-like behavior. The I-V characteristic was examined in the framework of the thermionic emission model. The ideality factor of the structure without PEDOT nanoparticle interface layer is 12.9. However, the ideality factor of the hybrid structure with PEDOT nanoparticle interface layer is obtained as 1.9. The value of ideality factor is dramatically decreased by inserting the PEDOT nanoparticle interface layer.
    Źródło:
    Acta Physica Polonica A; 2011, 119, 6; 875-879
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Two-Dimensional Automatic Control Modeling of a Posture Control System
    Autorzy:
    Park, K. S.
    Kim, U. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/90283.pdf
    Data publikacji:
    1998
    Wydawca:
    Centralny Instytut Ochrony Pracy
    Tematy:
    posture control model
    posturography
    perturbation
    parameter identification
    model fitness
    stability
    predictability
    model kontroli
    postura
    posturografia
    identyfikacja parametrów
    fitness
    Opis:
    A posture control model has been developed on the basis of the 2-dimensional feedback control theory. Human postural characteristics were investigated in 5 healthy participants. Tests were performed with eyes open and eyes closed. After 5 s of quiet standing, each participant was unexpectedly pulled forward by 30 mm at his pelvis height and then released. Postural sway was measured over 20 s at a rate of 100 per second. Transfer functions to represent the posture control characteristic were identified by the least squares' method. These showed good results of the model's fitness, predictability, and stability. The response of the eyes-closed condition to perturbation is more oscillatory than that of the eyes-open condition. It seems that the model identified could be applicable to ergonomics, sports, or clinical situations.
    Źródło:
    International Journal of Occupational Safety and Ergonomics; 1998, 4, 4; 485-498
    1080-3548
    Pojawia się w:
    International Journal of Occupational Safety and Ergonomics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Study Of The Die Roll Height Of SHP-1 And SCP-1 Materials In The Fine Blanking Process
    Badanie wysokości deformacji krawędzi wycinanych elementów ze stali SHP-1 i SCP-1 procesie wykrawania
    Autorzy:
    Lee, C. K.
    Kim, Y. C.
    Powiązania:
    https://bibliotekanauki.pl/articles/356499.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    die roll
    fine blanking
    SCP-1
    share speed
    SHP-1
    v-rings
    krawędzie
    wykrawanie
    szybkość działania
    deformacja
    Opis:
    The height of the die roll, the distance of the V-ring, and the shear rate were varied with the aim of investigating the effects of the applied changes on the fine blanking line in a cold-rolled and a pickled steel sheet, referred to as SCP-1 and SHP-1, respectively. Both materials consisted primarily of a ferrite phase with small amounts of impurities including F, Mn, and Cr. The distance was found to be a very important factor in controlling the shear of the V-ring in the fine blanking process. When the position of the V-ring was set at distances of 1.5 mm and 2 mm, the die roll height increased with increasing shear speeds from 6.4 m/min to 10 and 16 m/min. Analysis of the influence of the shear rate revealed that low rates resulted in the lowest die roll heights since the flow of material was effectively inhibited.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1397-1402
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Ship Collision Avoidance by Distributed Tabu Search
    Autorzy:
    Kim, D.
    Hirayama, K.
    Okimoto, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/116919.pdf
    Data publikacji:
    2015
    Wydawca:
    Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
    Tematy:
    Safety of Navigation
    Collision Avoidance
    Distributed Tabu Search Algorithm (DTSA)
    Distributed Local Search Algorithm (DLSA)
    Quasi-Local Minimum (QLM)
    Tabu Search Algorithm
    Local Search Algorithm
    Distributed Tabu Search
    Opis:
    More than 90% of world trade is transported by sea. The size and speed of ships is rapidly increasing in order to boost economic efficiency. If ships collide, the damage and cost can be astronomical. It is very difficult for officers to ascertain routes that will avoid collisions, especially when multiple ships travel the same waters. There are several ways to prevent ship collisions, such as lookouts, radar, and VHF radio. More advanced methodologies, such as ship domain, fuzzy theory, and genetic algorithm, have been proposed. These methods work well in one-on-one situations, but are more difficult to apply in multiple-ship situations. Therefore, we proposed the Distributed Local Search Algorithm (DLSA) to avoid ship collisions as a precedent study. DLSA is a distributed algorithm in which multiple ships communicate with each other within a certain area. DLSA computes collision risk based on the information received from neighboring ships. However, DLSA suffers from Quasi-Local Minimum (QLM), which prevents a ship from changing course even when a collision risk arises. In our study, we developed the Distributed Tabu Search Algorithm (DTSA). DTSA uses a tabu list to escape from QLM that also exploits a modified cost function and enlarged domain of next-intended courses to increase its efficiency. We conducted experiments to compare the performance of DLSA and DTSA. The results showed that DTSA outperformed DLSA.
    Źródło:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2015, 9, 1; 23-29
    2083-6473
    2083-6481
    Pojawia się w:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Study on Changes in Thickness of STS304 Material in the Progressive Drawing Process
    Autorzy:
    Lee, C. K.
    Kim, Y. C.
    Powiązania:
    https://bibliotekanauki.pl/articles/356710.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    body thickness
    drawing
    flange thickness
    corner roundness
    material thickness
    Opis:
    In the drawing process, the roundness of corners in the punch and the die are very important factors in determining the thicknesses of the product. The results clearly revealed that the thickness of a flange was increased and the thickness of body parts reduced when the roundness of the die entrance was small. The material thickness of the top part was decreased when the corner roundness of the punch was large. The smooth inflow of materials was found to have a significant effect on the thickness during the post-process. The compressive strength of STS 304 material exhibited a higher value compared with other processing methods. Moreover, we clearly observed the corner roundness of the punch and the die to be a very important factor for STS 304 materials.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1319-1323
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Application of Image Processing to Predict Compressive Behavior of Aluminum Foam
    Autorzy:
    Kim, S.
    Chung, H. J.
    Rhee, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/357032.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminum foam
    compute tomography (CT) image
    finite element method (FEM)
    Opis:
    An image processing technique was used to model the internal structure of aluminum foam in finite element analysis in order to predict the compressive behavior of the material. Finite element analysis and experimental tests were performed on aluminum foam with densities of 0.2, 0.25, and 0.3 g/cm3. It was found that although the compressive strength predicted from the finite element analysis was higher than that determined experimentally, the predicted compressive stress-strain curves exhibited a tendency similar to those determined from experiments for both densities. However, the behavior of the predicted compressive stress-strain curves was different from the experimental one as the applied strain increased. The difference between predicted and experimental stress-strain curves in a high strain range was due to contact between broken aluminum foam walls by the large deformation.
    Źródło:
    Archives of Metallurgy and Materials; 2016, 61, 2A; 635-640
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Causal relationship between supply chain dynamic capabilities, technological innovation, and operational performance
    Autorzy:
    Ju, K.-J.
    Park, B.
    Kim, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/407389.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    supply chain management
    dynamic capabilities
    supply chain dynamic capabilities
    technological innovation
    operational performance
    Opis:
    The aim of this study is to empirically examine the impact of supply chain dynamic capabilities on operational performance, and the mediating effect of technological innovation between dynamic capabilities and operational performance. This study is based on empirical data collected from a survey of 206 small- and medium-size firms in Korea. Structural equation modeling is used to test the research questions. The results show that supply chain dynamic capabilities positively influence technological innovation and operational performance of an enterprise. Additionally, structural equation analyses reveal that technological innovation plays a role as a partial mediator of the relationship between supply chain dynamic capabilities and operational performance. In a dynamic and ever-changing environment, the enforcement of dynamic capabilities in a sustainable supply chain is important for the innovation of technology and the improvement of operational performance. Further investigation is required to understand the differences by industries, characteristics of enterprises, and positions in a supply chain.
    Źródło:
    Management and Production Engineering Review; 2016, 7, 4; 6-15
    2080-8208
    2082-1344
    Pojawia się w:
    Management and Production Engineering Review
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Isotopic water separation using AGMD and VEMD
    Autorzy:
    Kim, J.
    Park, S.
    Kim, T.-S.
    Jeong, D.-Y.
    Ko, K.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/147314.pdf
    Data publikacji:
    2004
    Wydawca:
    Instytut Chemii i Techniki Jądrowej
    Tematy:
    AGMD
    VEMD
    oxygen isotopes
    PET
    FDG
    Opis:
    The 18O isotopic water permeation and separation characteristics of a hydrophobic PTFE membrane using Air Gap Membrane Distillation (AGMD) and Vacuum Enhanced Membrane Distillation (VEMD) were investigated. Permeation fluxes were measured by weighing the collected membrane-permeated water vapor. 18O/16O of each water sample was analyzed by the Tunable Diode Laser Absorption Spectroscopy (TDLAS). We observed the effects of the air filled membrane pores and the temperature gradient applied to the membrane surfaces on the vapor permeation flux and the oxygen isotope separation for the first time. For both AGMD and VEMD, the permeation flux and the degree of 18O separation increased as the membrane interfacial temperature gradient increased. Even though, oxygen isotope separation and the permeation flux for VEMD is slightly higher than AGMD, the latter may be more efficient from the system's operational point of view.
    Źródło:
    Nukleonika; 2004, 49, 4; 137-142
    0029-5922
    1508-5791
    Pojawia się w:
    Nukleonika
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of Hook Handles in a Pulling Task
    Autorzy:
    Kong, Y. K.
    Freivalds, A.
    Kim, S. E.
    Powiązania:
    https://bibliotekanauki.pl/articles/90931.pdf
    Data publikacji:
    2005
    Wydawca:
    Centralny Instytut Ochrony Pracy
    Tematy:
    handle evaluation
    finger/phalange force contributions
    hook pulling task
    uchwyt narzędziowy
    kończyna górna
    ergonomia
    ocena sprzętu i wyposażenia
    pozycja przy pracy
    Opis:
    To evaluate the effect of handle design characteristics on subjective ratings and pulling forces, meat-hook handles with various handle shapes, sizes, and hook positions were tested in a pulling task. Finger and phalange force data measured by force sensitive resistors and subjective ratings of discomfort were also evaluated. Generally subjects preferred 37-mm double frustum, 30-mm oval handles followed by 30-mm double frustum handles, 37-mm oval, and 45-mm double frustum handles. In the analyses of total pulling force, 37- and 45-mm double frustum handles showed less required pulling force than the others. The averages of finger force contributions to the total pulling force were 27.2, 28.1, 23.9, and 20.8% in order from index to little fingers. The average of phalange force contributions were 28.8, 33.6, and 37.6% for the distal, middle, and proximal phalanges, respectively. The findings illustrate that the pulling finger forces and subjective discomfort ratings were related to the handle shape as well as handle size.
    Źródło:
    International Journal of Occupational Safety and Ergonomics; 2005, 11, 3; 303-313
    1080-3548
    Pojawia się w:
    International Journal of Occupational Safety and Ergonomics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simulated impacts of rainfall extremes on yield responses of various barley varieties in a temperate region
    Autorzy:
    Yoon, C.Y.
    Kim, S.
    An, K.N.
    Powiązania:
    https://bibliotekanauki.pl/articles/2083065.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Instytut Agrofizyki PAN
    Tematy:
    barley
    rainfall
    simulation
    food cost
    grain
    yield
    Opis:
    As population rises, more people need to be fed. With increasing income, the potential exists for increases in the demand for cereals (i.e., barley). Since barley has a high level of tolerance to environmental stressors, this crop has been recommended as a potential crop for food security in marginal environments. In this study, a crop growth Agricultural Land Management Alternatives with Numerical Assessment Criteria model, was parameterized and used to simulate the yields of two barley types grown in a temperate environment at a latitude of 35°N. In order to apply this crop model to barley, 19 years of field data were used to model calibration and validation. As a result, the ALMANAC model accurately simulated yields for both barley types. The validated model was used to predict yields under three diverse seasonal rainfall scenarios associated with different patterns of the Central Pacific El Niño influence. According to the simulation results, excessively high seasonal rainfall decreased barley yields. Crop price and annual revenue of the two barley types were also evaluated using a non-linear regression model. For the malt type, the food price was higher with a higher rainfall, while naked barley had a higher revenue under the conditions of a lower rainfall.
    Źródło:
    International Agrophysics; 2021, 35, 2; 119-129
    0236-8722
    Pojawia się w:
    International Agrophysics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Building of CBR’s DB Using Ontology for a Collision Avoidance System
    Autorzy:
    Park, G. K.
    Kim, W. G.
    Benedictos, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/117348.pdf
    Data publikacji:
    2008
    Wydawca:
    Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
    Tematy:
    anticollision
    ontology
    Collision Avoidance System
    Case Based Reasoning (CBR)
    Fuzzy CBR Technique
    CBR Data Base
    Manoeuvring Situations
    Risk of Collision
    Opis:
    We have proposed Fuzzy-CBR to find a solution from past knowledge retrieved from the database and adapted to the new situation. However, ontology is needed in identifying concepts, relations and instances that are involved in a situation in order to improve and facilitate the efficient retrieval of similar cases from the CBR database. This paper proposes the way to apply ontology for identifying the concepts involved in a new case, used as inputs, for ship collision avoidance support system and in solving for similarity through document articulation and abstraction levels. These ontologies will be used to build a conceptual model of a manoeuvring situation.
    Źródło:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2008, 2, 4; 369-374
    2083-6473
    2083-6481
    Pojawia się w:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Enhanced Corrosion Resistance of Silicone-Coated Stents by Plasma Treatment
    Autorzy:
    Kim, H.
    Baik, K.
    Moon, M.
    Sung, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1187325.pdf
    Data publikacji:
    2016-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.65.-b
    Opis:
    The interfacial bonding of silicone-coated stents was characterized by field emission scanning electron microscopy and anodic potentiodynamic polarization tests. The coaxial in-lens secondary electron imaging revealed partial bonding between silicon rubber and nitinol alloy strips in both primer-treatment and plasma-treatment cases. Several strands between the polymer and stent substrate were observed in both cases and it seems that the bonding strength is the same. However, potentiodynamic polarization tests have shown that the corrosion rates of the plasma-treated nitinol stents were less than half of that of the primer-treated stents, indicating higher corrosion resistance. This enhanced corrosion resistance may be attributed to the modification of the physical properties of the surface of the stents by plasma treatments, making the oxide layer more effective than that of the primer-treated stents.
    Źródło:
    Acta Physica Polonica A; 2016, 129, 4; 857-860
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Compressive Deformation Behavior of Thick Micro-Alloyed HSLA Steel Plates at Elevated Temperatures
    Autorzy:
    Lee, J.-H.
    Kim, D.-O.
    Lee, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/351774.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    alloys
    rolling
    strain rate
    compression test
    HSLA steel
    Opis:
    The hot deformation behavior of a heavy micro-alloyed high-strength low-alloy (HSLA) steel plate was studied by performing compression tests at elevated temperatures. The hot compression tests were carried out at temperatures from 923 K to 1,223 K with strain rates of 0.002 s-1 and 1.0 s-1. A long plateau region appeared for the 0.002 s-1 strain rate, and this was found to be an effect of the balancing between softening and hardening during deformation. For the 1.0 s-1 strain rate, the flow stress gradually increased after the yield point. The temperature and the strain rate-dependent parameters, such as the strain hardening coefficient (n), strength constant (K), and activation energy (Q), obtained from the flow stress curves were applied to the power law of plastic deformation. The constitutive model for flow stress can be expressed as σ = (39.8 ln (Z) – 716.6) · ε(−0.00955ln(Z) + 0.4930) for the 1.0 s-1 strain rate and σ = (19.9ln (Z) – 592.3) · ε(−0.00212ln(Z) + 0.1540) for the 0.002 s-1 strain rate.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1191-1196
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Error reduction of the Doppler lidar signal using a re-normalization method
    Autorzy:
    Park, N G
    Baik, S H
    Park, S K
    Kim, D L
    Kim, D. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/173914.pdf
    Data publikacji:
    2014
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    injection-seeded laser
    Doppler lidar
    frequency locking
    wind lidar
    Doppler velocity measurement
    Opis:
    In this paper, we present a re-normalization method for a Doppler signal of a Doppler lidar system. For the Doppler lidar system, we used an injection-seeded pulsed Nd:YAG laser as a transmitter and an iodine cell as a Doppler frequency discriminator. A frequency locking system that uses the absorption feature of iodine gas is too sensitive to the external or internal noises (iodine cell temperature instability, laser frequency fluctuation, environmental noises, etc.) to maintain its locking point ideally, and this frequency locking error makes the Doppler lidar system acquire the noises as the Doppler frequency shifts. To reduce the Doppler signal error induced by a frequency locking error, we used a re-normalization method by an addition of a laser beam path separated from a transmitter to the Doppler frequency discriminator for re-normalization. In this method, fluctuations of the Doppler signal were reduced using the reference signal. The reduced amount of standard deviation between the Doppler signal and the re-normalization signal was 4.838×10–3 and the Doppler signals showed a 53.3% fluctuation reduction of the averaged error value by this method.
    Źródło:
    Optica Applicata; 2014, 44, 1; 103-111
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study on Crystal Structure and Magnetic Properties of Ba4Co2Fe36O60 by Sol-Gel Method
    Autorzy:
    Jeong, K.-P.
    Yang, S.-W.
    Kim, J.-G.
    Powiązania:
    https://bibliotekanauki.pl/articles/351655.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    U-type ferrite
    sol-gel method
    nano-powder
    Opis:
    U-type ferrite typified by Ba4Co2Fe36O60 is used as a RAM (Radar Absorbing Materials) in the X-band (8-12 GHz). Ba4Co2Fe36O60 is known to have a complex crystal structure, which makes it difficult to obtain single phase and have low reproducibility. Previously known U-type ferrites have been fabricated based on a ceramic process that mixing (by a ball mill), calcining, grinding, binder mixing, drying, sieving, pressing and sintering. In contrast, the process of preparing the powder by the sol-gel method and its heat-treating is advantageous in that it can reduce the process steps and the required time. In addition, the precise stoichiometric control by the sol-gel method can effectively evaluate the effect of added or substituted elements. In this study investigates the crystal structure of Ba4Co2Fe36O60 synthesized by the sol-gel method and the morphology of U-type ferrite nano-powders according to various heat treatment conditions. Analysis of the crystal structure is used for XRD. Morphology and size are observed by SEM. In addition, VSM is performed to confirm the change of magnetic properties according to various heat treatment conditions.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1449-1452
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Experimental Study On Fracture Property Of Double Cantilever Beam Specimen With Aluminum Foam
    Doświadczalne badanie pękania mimośrodowo rozciąganej próbki z bocznym karbem wykonanej z piany aluminiowej
    Autorzy:
    Kim, Y. C.
    Choi, H. K.
    Cho, J. U.
    Powiązania:
    https://bibliotekanauki.pl/articles/351465.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminium foam
    double cantilever beam
    fracture energy
    adhesively bonded structure
    piana aluminiowa
    podwójna belka wspornikowa
    energia pękania
    Opis:
    This study aims to investigate double cantilever beam specimen with aluminum foam bonded by spray adhesive to investigate the fracture strength of the adhesive joint experimentally. The fracture energy at opening mode is calculated by the formulae of British Engineering Standard (BS 7991) and International Standard (ISO 11343). For the static experiment, four types of specimens with the heights (h) of 25 mm, 30 mm, 35 mm and 40 mm are manufactured and the experimental results are compared with each other. As the height becomes greater, the fracture energy becomes higher. After the length of crack reaches 150 mm, the fracture energy of the specimen (h=35 mm) is greater than that of the specimen (h=40 mm). Fatigue test is also performed with DCB test specimen. As the height decreases, the fracture energy becomes higher. By the result obtained from this study, aluminum foam with adhesive joint can be applied to actual composite structure and its fracture property can possibly be anticipated.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1151-1154
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of Cu-Based SiC Composites by Spark Plasma Sintering of Cu-Nitrate Coated SiC Powders
    Autorzy:
    Jeong, Y.-K.
    Kim, Y. S.
    Oh, S.-T.
    Powiązania:
    https://bibliotekanauki.pl/articles/354995.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Cu-SiC composite
    Cu-nitrate
    spark plasma sintering
    microstructure
    Opis:
    An optimum route to fabricate the Cu-based SiC composites with homogeneous microstructure was investigated. Three methods for developing the densified composites with sound interface between Cu and SiC were compared on the basis of the resulting microstructures. Starting with three powder mixtures of elemental Cu and SiC, elemental Cu and PCS coated SiC or PCS and Cunitrate coated SiC was used to obtain Cu-based SiC composites. SEM analysis revealed that the composite fabricated by spark plasma sintering using elemental SiC and Cu powder mixture showed inhomogeneous microstructure. Conversely, dense microstructure with sound interface was observed in the sintered composites using powder mixture of pre-coated PCS and Cu-nitrate onto SiC. The relationship between powder processing and microstructure was discussed based on the role of coating layer for the wettability.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1407-1410
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Novel Extraction Process Of Rare Earth Elements From NdFeB Powders Via Alkaline Treatment
    Nowy sposób ekstrakcji pierwiastków ziem rzadkich z proszków NdFeB w roztworach alkalicznych
    Autorzy:
    Chung, K. W.
    Kim, C.-J.
    Yoon, H.-S.
    Powiązania:
    https://bibliotekanauki.pl/articles/355324.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    recycling
    NdFeB magnet
    alkaline treatment
    leaching
    selective leaching efficiency
    recykling
    magnes neodymowy
    obróbka alkaliczna
    ługowanie
    wydajność
    Opis:
    The alkaline treatment of NdFeB powders in NaOH solution at various equivalent amounts of NaOH at 100°C was performed. The resultant powders were then leached in 0.5M H2SO4 solution at 25°C for 2 minutes. At 5 equivalents of NaOH, neodymium in NdFeB powders was partially transformed to neodymium hydroxide. The transformation of neodymium to neodymium hydroxide actually occurred at 10 equivalents of NaOH and was facilitated by increasing the equivalent of NaOH from 10 to 30. In addition, iron was partially transformed to magnetite during the alkaline treatment, which was also promoted at a higher equivalent of NaOH. The leaching yield of neodymium from alkaline-treated powders was increased with an increasing equivalent of NaOH up to 10; however, it slightly decreased with the equivalent NaOH of over 10. The leaching yield of iron was inversely proportional to that of rare earth elements. NdFeB powders treated at 10 equivalents of NaOH showed a maximum leaching yield of neodymium and dysprosium of 91.6% and 94.6%, respectively, and the lowest leaching yield of iron of 24.2%, resulting in the highest selective leaching efficiency of 69.4%.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1301-1305
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Warm Tensile Deformation Behavior and Constitutive Equation of Supersaturated Solid-Solutionized Al-9Mg Extruded Alloy
    Autorzy:
    Yang, Seung Y.
    Kim, Bong H.
    Lee, Da B.
    Choi, Kweon H.
    Kim, Nam S.
    Ha, Seong H.
    Yoon, Young O.
    Lim, Hyun K.
    Kim, Shae
    Kim, Young J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2048882.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminum alloy
    Al-9Mg alloy
    tensile test
    constitutive equation
    Opis:
    In this paper, as a purpose to apply the supersaturated solid-solutionized Al-9Mg alloy to the structural sheet parts of automotive, tensile tests were conducted under the various conditions and a constitutive equation was derived from the tensile test results. Al-9Mg alloy was produced using a special Mg master alloy containing Al2Ca during the casting process and extruded into the sheet. In order to study the deformation behavior of Al-9Mg alloy in warm temperature forming environments, tensile tests were conducted under the temperature of 373 K-573 K and the strain rate of 0.001/s~0.1/s. in addition, by using the raw data obtained from tensile tests, a constitutive equation of the Al-9Mg alloy was derived for predicting the optimized condition of the hot stamping process. Al-9Mg alloy showed uncommon deformation behavior at the 373 K and 473 K temperature conditions. The calculated curves from the constitutive equation well-matched with the measured curves from the experiments particularly under the low temperature and high strain rate conditions.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 4; 1013-1018
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure and Mechanical Properties of Hot-deformed AlMg4 Alloys with the Variations of Mn, Fe, and Si Contents
    Autorzy:
    Lee, Da B.
    Kim, Bong H.
    Choi, Kweon H.
    Yang, Seung Y.
    Kim, Nam S.
    Ha, Seong H.
    Yoon, Young O.
    Lim, Hyun K.
    Kim, Shae
    Hyun, Soong K..
    Powiązania:
    https://bibliotekanauki.pl/articles/351603.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg alloy
    intermetallic compounds
    homogenization
    hot-rolling
    microstructure
    Opis:
    This paper aims to investigate the microstructural evolution and mechanical properties of hot-deformed AlMg4 alloys with Mn, Fe, and Si as the main impurities. For this purpose, solidification behavior and microstructural evolution during hot-rolling and heat-treatment processes are investigated by using theoretical calculations and experimental characterization. The crystallization and morphological transformation of intermetallic Al3 Fe, Al6 Mn, and Mg2 Si phases are revealed and discussed in terms of the variation in chemical composition. Following a homogenization heat-treatment, the effect of heat treatment on the intermetallic compounds is also investigated after hot-rolling. It was revealed that the Mg2 Si phase can be broken into small particles and spherodized more easily than the Al3 Fe intermetallic phase during the hot-rolling process. For the Mn containing alloys, both yield and ultimate tensile strength of the hot-rolled alloys increased from 270 to 296 MPa while elongation decreased from 17 to 13%, which can be attributed to Mn-containing intermetallic as well as dispersoid.
    Źródło:
    Archives of Metallurgy and Materials; 2020, 65, 4; 1255-1259
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Electrochemical Properties of Flexible Anode with SnO2 Nanopowder for Sodium-Ion Batteries
    Autorzy:
    Kim, Huihun
    Sadan, Milan K.
    Kim, Changhyeon
    Choi, Ga-In
    Seong, Minjun
    Cho, Kwon-Koo
    Kim, Ki-Won
    Ahn, Jou-Hyeon
    Ahn, Hyo-Jun
    Powiązania:
    https://bibliotekanauki.pl/articles/2049149.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    word
    sodium-ion batteries
    SnO2 anode
    flexible electrode
    nano SnO2 particles
    ether based electrolyte
    Opis:
    Sodium-ion batteries (SiBs) have attracted substantial interest as an alternative to lithium-ion batteries because of the low cost. There have been many studies on the development of new anode materials that could react with sodium by conversion mechanism. SnO2 is a promising candidate due to its low cost and high theoretical capacity. However, SnO2 has the same problem as other anodes during the conversion reaction, i.e., the volume of the anode repeatedly expands and contracts by cycling. Herein, anode is composed of carbon nanofiber embedded with SnO2 nanopowder. The resultant electrode showed improvement of cyclability. The optimized SnO2 electrode showed high capacity of 1275 mAh g-1 at a current density of 50 mA g-1. The high conductivity of the optimized electrode resulted in superior electrochemical performance.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 4; 931-934
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Variable-Focus Fluid Lens Using an Electromagnetic Actuator
    Autorzy:
    Lee, J.
    Park, K.
    Choi, J.
    Kim, H.
    Kong, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1399681.pdf
    Data publikacji:
    2013-02
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    85.85.+j
    42.79.Bh
    Opis:
    A variable-focus fluid lens controlled by an electromagnetic actuator and its characteristics are presented in this paper. The repulsive force between an NdFeB magnet and a solenoid through electromagnetic induction causes deflections in the elastomeric membranes integrated in the lens resulting in a focal-length change. The controllability of the focal length of the fabricated lens with an aperture size of 2 mm was approximately from infinity to 15 mm (with input current of 100 mA). The actuator including the solenoid was carefully designed to avoid thermal crosstalk of the lens fluid and magnet from the electromagnetic induction of the solenoid. The settling time to form a convex shape of the lens membrane was approximately 2.5 ms at an input current of 20 mA.
    Źródło:
    Acta Physica Polonica A; 2013, 123, 2; 202-204
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spontaneous Formation of Titanium Nitride on the Surface of a Ti Rod Induced by Electro-Discharge-Heat-Treatment in an N2 Atmosphere
    Autorzy:
    Lee, W. H.
    Yoon, Y. H.
    Kim, Y. H.
    Lee, Y. K.
    Kim, J. Y.
    Chang, S. Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/352477.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    titanium
    surface modification
    diffusion
    heat treatment
    XPS
    Opis:
    A single pulse of 2.0 to 3.5 kJ of input energy from a 450 mF capacitor was applied to a commercially pure Ti rod in a N2 atmosphere. The surface of the Ti rod transformed from TiO2 into titanium nitride in times as short as 159 msec, providing a bimodal morphology of the cross-section. A much higher value of hardness that was observed at the edge of the cross-section was attributed to nitrogen-induced solid-solution hardening that occurred during the electrical discharge process. The activation energy (Ea) for the diffusion process was estimated to be approximately 86.9 kJ/mol. Results show that the electrical discharge process is a possible potential method for the nitriding of Ti; advantages include a short processing time and control of the nitrided layer without dimensional changes.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1281-1285
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of Substituted Elements on Reflection Loss of Ba-Ferrite Nanoparticle
    Autorzy:
    Yang, S.
    Jeong, K.-P.
    Park, S.-Y.
    Kim, J.-G.
    Powiązania:
    https://bibliotekanauki.pl/articles/352041.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ba ferrite
    substitutional m-type ferrite
    reflection loss
    sol-gel
    additional atom
    Opis:
    Due to the rapid development of the information communication industries, it is expected that next-generation mobile communication devices in the data communication environment will be used at the same time in the L~X band (1–12 GHz). To mutual electric wave interference prevention, research on wave absorbers in L~X band is needed. In this paper, barium ferrite was researched as L~X band wave absorber. The Barium ferrite (BaM, Ba ferrite) substituted by divalent ions (Co2+, Cu2+, Ni2+, Zn2+) and tetravalent ion (Ti4+). The substituted Ba ferrite nanoparticles were fabricated by sol-gel process. Lattice parameter, particle size, magnetic properties, and reflection loss were analyzed by X-ray diffraction (X-RD), a Vibrating Sample Magnetometer (VSM), and a Network Analyzer. Lattice parameter of Ba ferrite was changed 0.0005 to 0.0078 Å in a-b direction, and 0.0187 to0.0445 Å in c-direction by substituted elements, and it influenced on magnetic anisotropy. In addition, Co-Ti substitution elements influenced that coercive force decrease 5,739 to 2,240 Oe. Moreover, reflection loss frequencies were shifted from 16.3 GHz to 14.4 and 17.4 GHz by substituted elements Co-Ti and Zn-Ti.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1201-1204
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Surface Treatment And Modification Of Graphene Using Organosilane And Its Thermal Stability
    Obróbka powierzchniowa i modyfikacja grafenu przy użyciu organosilanu i jego stabilność termiczna
    Autorzy:
    Kim, D.-S.
    Dhand, V.
    Rhee, K.-Y.
    Park, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/354056.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    graphite
    thermal properties
    Raman spectroscopy
    surface treatment
    3-APTES
    grafit
    właściwości termiczne
    spektroskopia Ramana
    obróbka powierzchniowa
    Opis:
    In this study, graphene was functionalized via acid oxidation in the presence of a mixture of concentrated sulfuric acid and nitric acid. The oxidized graphene was silanized using the coupling agent, 3-aminopropyltriethoxsilane, resulting in functionalized graphene. The oxidized graphene and functionalized graphene were characterized by X-Ray diffraction, Fourier transform infrared spectroscopy, High-resolution micro Raman spectroscopy, thermogravimetric analysis, and atomic force microscopy to confirm the presence of functional moieties on the graphene surface. Thermal studies also demonstrate that the functionalized material is thermally stable up to higher temperatures.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1387-1391
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optical Mini-Disk Resonator Integrated into a Compact Optoelectronic Oscillator
    Autorzy:
    Salzenstein, P.
    Tavernier, H.
    Volyanskiy, K.
    Kim, N.
    Larger, L.
    Rubiola, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/1795637.pdf
    Data publikacji:
    2009-10
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    06.30.Ft
    43.50.Yw
    87.64.M-
    87.57.cm
    Opis:
    This work consists in the design, fabrication and characterization of mini-disk $MgF_{2}$ resonators for integration into optoelectronic oscillator and first experimental results of implementation in microwave free spectral range oscillator with taper coupling optoelectronic oscillator.
    Źródło:
    Acta Physica Polonica A; 2009, 116, 4; 661-663
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Hafnium and Zirconium to Glass Forming Ability, Thermal Stability, Plasticity Deformation and Crystallization of Ni-Free Pentabasic Ti-Based Bulk Metallic Glasses
    Autorzy:
    Oak, J.-J.
    Kim, Y. H.
    Bae, K.-C.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/352087.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ti-based alloy
    metallic glass
    Ti fiber
    glass formability
    plastic deformation
    Opis:
    The newly designed Ti-based bulk metallic glass (BMG) in which case of fracture behavior was observed 1990MPa to compressive strength with a wide plastic deformation around 7% after process of elastic deformation. This phenomenon can be compared with those of Ti-based alloys and other Ti-based BMGs and indicates high potential to be applied in use. It was evaluated the Ti-based BMG for thermal stability that the reduced glass parameters, ΔTx, Trg and γ, are 79K, 0.50 and 0.38, respectively. In addition, it reveals high activation energies for crystallization in which are estimated to Ex1 = 291.77 ±9.71 kJ/mol, Ex2 = 588.77 ±28.88 kJ/mol and Ex3 = 330.26 ±3.61 kJ/mol on kissinger plotting in this study.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1081-1087
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    High Temperature Oxidation Property of SiC Coating Layer Fabricated by Aerosol Deposition Process
    Autorzy:
    Ham, G.-S.
    Kim, S.-H.
    Park, J.-Y.
    Lee, K.-A.
    Powiązania:
    https://bibliotekanauki.pl/articles/352142.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    silicon carbide
    aerosol deposition
    coating
    high temperature oxidation
    Opis:
    This study investigated the high temperature oxidation property of SiC coated layer fabricated by aerosol deposition process. SiC coated layer could be successfully manufactured by using pure SiC powders and aerosol deposition on the Zr based alloy in an optimal process condition. The thickness of manufactured SiC coated layer was measured about 5 μm, and coating layer represented high density structure. SiC coated layer consisted of α-SiC and β-SiC phases, the same as the initial powder. The initial powder was shown to have been crushed to the extent and was deposited in the form of extremely fine particles. To examine the high temperature oxidation properties, oxidized weight gain was obtained for one hour at 1000°C by using TGA. The SiC coated layer showed superior oxidation resistance property than that of Zr alloy (substrate). The high temperature oxidation mechanism of SiC coated layer on Zr alloy was suggested. And then, the application of aerosol deposited SiC coated layer was also discussed.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1347-1351
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal Diffusion of 57Co into Rh Foil for Preparing Mössbauer Source
    Autorzy:
    Uhm, Y. R.
    Kim, J. J.
    Choi, S. M.
    Son, K. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/352775.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Mössbauer source
    diffusion
    electroplating
    57Co/Rh
    Opis:
    To establish the coating conditions for 57 Co, non-radioactive Co ions are dissolved in an acid solution and electroplated on to a rhodium plate. The thermal diffusion of electroplated Co into a rhodium matrix was studied to apply a 57 Co Mössbauer source. The procedure to form a Co deposited onto Rh foil was established using two different electroplating baths: the acid-based buffer (pH 3) containing boric acid, sodium chloride, and saccharin, and the alkaline-based buffer (pH 10) containing hydrazine hydrate and ammonium citrate. The influence of different annealing conditions was investigated. From the results, the best diffusion degree of electrodeposited Co onto the rhodium matrix was obtained in an annealing process performed at 1100°C for 3 h in vacuum over 10-5 hPa.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1249-1252
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure Development of Spark Plasma Sintered Ti-Nb Alloy by Heat Treatment
    Autorzy:
    Haq, M. A.
    Abbas, S. F.
    Eom, N. S. A.
    Kim, T. S.
    Lee, B.
    Park, K.-T.
    Kim, B. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/355593.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    TiNb alloy
    Spark plasma sintering
    Heat treatment
    Microstructure
    β-phase titanium
    Opis:
    The β-phase Titanium (β-Ti) alloys have been under the spotlight in the recent past for their use as biomedical prosthetic materials owing to their excellent properties such as low elastic modulus, high corrosion resistance and tensile strength. Recently, Niobium (Nb) has gained a lot of attention as a β-phase stabilizing element in Ti alloys to replace Vanadium (V) due to its excellent solubility in Ti, low elastic modulus and biocompatibility. In this work, low cost Ti-20Nb binary alloy has been fabricated via powder metallurgy procedures. The blended powder mixtures of Ti and Nb were sintered at 900°C for 20 mins by the Spark Plasma Sintering (SPS) with an applied uniaxial pressure of 40 MPa. The heating rate was fixed at 50°C/min. The sintered alloy was subject to heat treatments at 1200°C in vacuum condition for various time durations. The characterizations of microstructure obtained during this process were done using FE-SEM, EDS and XRD. By increasing heat treatment time, as understood, the volume of residual Nb particles was decreased resulting in accelerated diffusion of Nb into Ti. Micro hardness of the alloy increased from 340 to 355 HV with the increase in β phase content from 30 to 45%. The resultant alloys had relatively high densities and homogenized microstructures of dispersed lamellar β grains in α matrix.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1429-1432
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Growth of NdBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ Superconducting Thin Films on SrTiO$\text{}_{3}$(100) and LaSrGaO$\text{}_{4}$(100) Substrates
    Autorzy:
    Park, J.-C.
    Ha, D. H.
    Kim, I.-S.
    Park, Y.K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1964239.pdf
    Data publikacji:
    1997-07
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    74.76.Bz
    Opis:
    NdBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ superconducting thin films were grown on SrTiO$\text{}_{3}$(100) and LaSrGaO$\text{}_{4}$(100) substrates by off-axis rf sputtering and pulsed laser deposition. The effects of several deposition parameters, e.g. gas pressure, substrate temperature and energy density were studied. Thin films grown by off-axis rf sputtering were highly c-axis oriented, but those by pulsed laser deposition were predominantly a-axis oriented under our deposition conditions. However, the c-axis oriented portion for the films grown by pulsed laser deposition was increased by increasing the temperature above 800°C. T$\text{}_{c(zero)}$ was 87 K and 83 K for the c- and a-axis oriented films respectively. The critical current density of c-axis oriented films was 10$\text{}^{6}$-10$\text{}^{7}$ A/cm$\text{}^{2}$ below 60 K.
    Źródło:
    Acta Physica Polonica A; 1997, 92, 1; 105-114
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Fe Content on the Microstructure and Mechanical Properties of Ti-Al-Mo-V-Cr-Fe Alloys
    Autorzy:
    Bae, K.-C.
    Oak, J.-J.
    Kim, Y. H.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/351896.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ti alloy
    near-β titanium alloy
    aircraft applications
    structural material
    landing gear
    Opis:
    To investigate the effect of Fe content on the correlation between the microstructure and mechanical properties in near-b titanium alloys, the Ti-5Al-5Mo-5V-1Cr-xFe alloy system has been characterized in this study. As the Fe content increased, the number of nucleation sites and the volume fraction of the α phase decreased. We observed a significant difference in the shape and size of the α phase in the matrix before and after Fe addition. In addition, these morphological deformations were accompanied by a change in the shape of the α phase, which became increasingly discontinuous, and changed into globular-type α phase in the matrix. These phenomena affected the microstructure and mechanical properties of Ti alloys. Specimen #2 exhibited a high ultimate tensile strength (1071 MPa), which decreased with further addition of Fe.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1105-1108
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure Evolution of Ni-Based ODS Superalloy Powders During Horizontal Rotary Ball Milling
    Autorzy:
    Lee, H.-E.
    Kim, Y. S.
    Park, J. K.
    Oh, S.-T.
    Powiązania:
    https://bibliotekanauki.pl/articles/355552.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    high energy ball milling
    Ni-base ODS superalloy
    particle and crystalline size
    microstructure
    Opis:
    Microstructure evolution of Ni-based oxide dispersion-strengthened alloy powders with milling time is investigated. The elemental powders having a nominal composition of Ni-15Cr-4.5Al-4W-2.5Ti-2Mo-2Ta-0.15Zr-1.1Y2O3 in wt % were ball-milled by using horizontal rotary ball milling with the change of milling velocity. Microstructure observation revealed that large aggregates were formed in the early stages of ball milling, and further milling to 5 h decreased particle size. The average crystalline size, estimated by the peak broadening of XRD, decreased from 28 nm to 15 nm with increasing milling time from 1 h to 5 h. SEM and EPMA analysis showed that the main elements of Ni and Cr were homogeneously distributed inside the powders after ball milling of 5 h.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1253-1255
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Manufacturing and Macroscopic Properties of Y2O3 Coating Layer on Ceramic (AlN) Substrate Fabricated by Aerosol Deposition
    Autorzy:
    Wi, D.-Y.
    Ham, G.-S.
    Kim, S.-H.
    Lee, K.-A.
    Powiązania:
    https://bibliotekanauki.pl/articles/353052.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aerosol deposition
    Y2O3 coating layer
    AlN matrix
    nano indentation
    Opis:
    This study attempted to manufacture an Y2O3 ceramic coating layer on a ceramic (AlN) substrate using aerosol deposition (AD) and investigated its macroscopic properties. Pure Y2O3 powder with a polygonal shape and average size of 5.0 μm was used as initial feedstock. Using aerosol deposition with suitable process conditions, an Y2O3 coating layer was successfully fabricated on aluminum nitride (AIN). The thickness of the manufactured coating layer was approximately 10 mm. The coating layer consisted of Y2O3 phase identical to that in the initial powder, and no additional oxides were identified. In regard to the roughness of the Y2O3 coating layer, the average roughness (Ra) measured 1.32 μm, indicating that the surface roughness was relatively even compared to the initial powder size (5 μm). Mechanical properties of the Y2O3 coating layer were measured using nano indentation equipment, and the indentation modulus of the Y2O3 coating layer fabricated by aerosol deposition measured 136.5 GPa. The interface of the coating layer was observed using TEM, and the deposition mechanism of the Y2O3 coating layer manufactured by aerosol deposition was also discussed.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1463-1466
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication Of Porous Ti By Thermal Decomposition And Sintering Of PMMA/TiH2 Powder Compact
    Wytwarzanie porowatego tytanu przez rozkład termiczny i spiekanie wyprasek PMMA/TiH2
    Autorzy:
    Jeon, K. Ch.
    Kim, Y. D.
    Suk, M.-J.
    Oh, S.-T.
    Powiązania:
    https://bibliotekanauki.pl/articles/352341.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    porous Ti
    PMMA powders
    thermal decomposition of TiH2
    pore structure
    porowaty tytan
    PMMA
    rozkład termiczny
    struktura porów
    Opis:
    Porous Ti with controlled pore structure was fabricated by thermal decomposition and sintering process using TiH2 powders and Polymethylmethacrylates (PMMA) beads as pore forming agent. The beads sizes of 8 and 50 μm were used as a template for fabricating the porous Ti. The TiH2 powder compacts with 20 and 70 vol% PMMA were prepared by uniaxial pressing and sintered for 2 h at 1100°C. TGA analysis revealed that the PMMA and TiH2 were thermally decomposed at about 400°C forming pores and at about 600°C into metallic Ti phase. The porosity increased with increase in the amount of PMMA addition. Also, the microstructure observation showed that the pore size and shape were strongly dependent on the PMMA shapes.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1375-1377
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Self-Consolidation and Surface Modification of Mechanical Alloyed Ti-25.0 at.% Al Powder Mixture by Using an Electro-Discharge Technique
    Autorzy:
    Chang, S. Y.
    Jang, H. S.
    Yoon, Y. H.
    Kim, Y. H.
    Kim, J. Y.
    Lee, Y. K.
    Lee, W. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/354212.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sintering
    mechanical alloying
    powder consolidation
    intermetallic compounds
    titanium aluminides
    Opis:
    Electrical discharges using a capacitance of 450 μF at 0.5, 1.0, and 1.5 kJ input energies were applied in a N2 atmosphere to obtain the mechanical alloyed Ti3Al powder without applying any external pressure. A solid bulk of nanostructured Ti3Al was obtained as short as 160 μsec by the Electrical discharge. At the same time, the surface has been modified into the form of Ti and Al nitrides due to the diffusion process of nitrogen to the surface. The input energy was found to be the most important parameter to affect the formation of a solid core and surface chemistry of the compact.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1293-1297
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Self-Consolidation Mechanism of Ti5Si3 Compact Obtained by Electro-Discharge-Sintering Directly from Physically Blended Ti-37.5 At.% Si Powder Mixture
    Autorzy:
    Chang, S. Y.
    Cheon, Y. W.
    Yoon, Y. H.
    Kim, Y. H.
    Kim, J. Y.
    Lee, Y. K.
    Lee, W. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/353022.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sintering
    mechanical alloying
    powder consolidation
    intermetallic compounds
    titanium silicide
    Opis:
    Characteristics of electro-discharge-sintering of the Ti-37.5at.% Si powder mixture was investigated as a function of the input energy, capacitance, and discharge time without applying any external pressure. A solid bulk of Ti5Si3 was obtained only after in less than 129 μsec by the EDS process. During a discharge, the heat is generated to liquefy and alloy the particles, and which enhances the pinch pressure can condensate them without allowing a formation of pores. Three step processes for the self-consolidation mechanism during EDS are proposed; (a) a physical breakdown of oxide film on elemental as-received powder particles, (b) alloying and densifying the consolidation of powder particles by the pinch pressure, and (c) diffusion of impurities into the consolidated surface.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1299-1302
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Biological Evaluation of Anodized Biodegradable Magnesium-Calcium Alloys
    Autorzy:
    Kim, J.
    Lee, J.
    Lee, K.
    Park, S.
    Lim, H.
    Park, C.
    Bae, J.
    Yun, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1398763.pdf
    Data publikacji:
    2016-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    87.85.jj
    87.85.J-
    Opis:
    The objective of this study was to evaluate the biocompatibility of studied binary magnesium-calcium (Mg-Ca) alloys for biodegradable intraosseous implants. Mg is necessary for health and is a non-toxic biodegradable material that decomposes naturally in the body. Nevertheless, Mg has been implicated in problems including diminished physical properties and corrosion resistance when degradation is too rapid prior to bone healing. This study has explored the effect of Ca on the corrosion resistance and biological evaluation after anodizing treatment with different contents of Ca alloy. Binary Mg-0.5Ca, Mg-1Ca and Mg-5Ca alloys were prepared by the casting method under an argon atmosphere and cut into disc-shaped pieces. Pure Mg alloy was used as the control. Anodic oxidation was performed for 15 minutes at a voltage of 120 V using an electrolyte solution containing Ca gluconate, sodium hexametaphosphate, and sodium hydroxide at room temperature. Corrosion resistance was analyzed using a corrosion tester. After a hydrogen evolution test, the surface pattern and phase changes were observed on a scanning electron microscop (SEM) and energy dispersive spectroscop (EDS). Microscopic evaluation of the adhesion and cell biological functions of Mg was conducted by observing the response of human fetal osteoblastic 1.19 cells with regard to changes in surface film properties, depending on the amount of Ca. Our results support the view that in Mg-xCa alloys (x=0.5, 1, 5 wt.%) treated using anodic oxidation, the increasing Ca content controls the rate of decomposition and improves corrosion resistance.
    Źródło:
    Acta Physica Polonica A; 2016, 129, 4; 728-735
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison of body surface area-based and weight-based dosing format for oral prednisolone administration in small and large-breed dogs
    Autorzy:
    Nam, A.
    Kim, S.M.
    Jeong, J.W.
    Song, K.H.
    Koo, T.S.
    Seo, K.W.
    Powiązania:
    https://bibliotekanauki.pl/articles/2087897.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Źródło:
    Polish Journal of Veterinary Sciences; 2017, 3; 611-613
    1505-1773
    Pojawia się w:
    Polish Journal of Veterinary Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication and Characterization of CoCrFeNiMn High Entropy Alloy Powder Processed by Gas Atomization
    Autorzy:
    Park, T. G.
    Lee, S. H.
    Lee, B.
    Cho, H. M.
    Choi, W. J.
    Kim, B. S.
    Shin, K. S.
    Kim, T.-S.
    Powiązania:
    https://bibliotekanauki.pl/articles/353649.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    high entropy alloy
    gas atomization
    spark plasma sintering
    CoCrFeNiMn
    Opis:
    In this study, precisely controlled large scale gas atomization process was applied to produce spherical and uniform shaped high entropy alloy powder. The gas atomization process was carried out to fabricate CoCrFeNiMn alloy, which was studied for high ductility and mechanical properties at low temperatures. It was confirmed that the mass scale, single phase, equiatomic, and high purity spherical high entropy alloy powder was produced by gas atomization process. The powder was sintered by spark plasma sintering process with various sintering conditions, and mechanical properties were characterized. Through this research, we have developed a mass production process of high quality and spherical high entropy alloy powder, and it is expected to expand applications of this high entropy alloy into fields such as powder injection molding and 3D printing for complex shaped components.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 1055-1059
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study of Ti, V and Their Oxides-Based Thin Films in the Search for Hydrogen Storage Materials
    Autorzy:
    Tarnawski, Z.
    Zakrzewska, K.
    Kim-Ngan, N.-T.
    Krupska, M.
    Sowa, S.
    Drogowska, K.
    Havela, L.
    Balogh, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/1401913.pdf
    Data publikacji:
    2015-09
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.15.Cd
    68.49.-h
    61.05.C-
    68.60.-p
    Opis:
    Thin film series consisting of Ti, V, TiO₂ and V₂O₅ layer with different layer geometries, sequences and thicknesses have been prepared by the sputtering technique. The hydrogen depth profile of selected films upon hydrogen charging at 1 bar and/or hydrogenation at pressure up to 102 bar was determined by using secondary ion mass spectrometry and nuclear reaction analysis using a N-15 beam. The highest hydrogen storage with a concentration up to 50 at.% was found in the pure Ti and Ti-contained layer, while it amounts to around 30% in the metallic Ti-V-Ni layer. Hydrogen can diffuse through the TiO₂ layer without accumulation, but can be stored in the VO₂ layer in some cases. Hydrogen can remove the preferential Ti orientation in the films and induce a complete transition of V₂O₅ into VO₂ in the films.
    Źródło:
    Acta Physica Polonica A; 2015, 128, 3; 431-439
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of Surface Characteristics and Physical Properties on Biodegradable Magnesium-Calcium Alloys by Anodic Oxidation
    Autorzy:
    Kim, J.
    Lee, J.
    Yang, H.
    Park, S.
    Lim, H.
    Oh, G.
    Yun, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1191716.pdf
    Data publikacji:
    2016-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    87.85.jj
    87.85.jc
    Opis:
    The purpose of this study was to determine the effect of calcium (Ca) on the surface characteristics and physical properties of magnesium-calcium alloys after anodization. A novel binary alloy Mg-xCa (in which x=0.5, 1, or 5 wt.%) was cast by combining magnesium (99.9%) and calcium (99.9%) in an argon gas (99.99%) atmosphere. A magnesium alloy rod having a diameter of 15 mm was cut into discs, each 2 mm thick. The specimens were subjected to anodic oxidation at 120 V for 15 minutes at room temperature in an electrolyte solution consisting of calcium gluconate, sodium hexametaphosphate, and sodium hydroxide. Surface and cross-sectional morphological changes were observed using scanning electron microscopy, and the microstructures and phases were detected by means of X-ray diffraction. Hardness and surface roughness were assessed by means of a Vickers hardness tester and a surface roughness meter, respectively. The results show that the physical properties of these magnesium-calcium alloys have been improved, because it was possible to control the dissolution rate according to the amount of calcium added.
    Źródło:
    Acta Physica Polonica A; 2016, 129, 4; 736-741
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Morphology of strobili at different development positions and cone and seed characteristics of Pinus densiflora f. multicaulis
    Autorzy:
    Kwon, S.H.
    Kim, Y.G.
    Kang, H.I.
    Shim, D.
    Kang, K.S.
    Powiązania:
    https://bibliotekanauki.pl/articles/2078259.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Instytut Dendrologii PAN
    Tematy:
    bisexual strobili
    sex reversal
    microsporangia
    megasporangia
    cone analysis
    Opis:
    Pinus densiflora f. multicaulis is a rare and unusual form of genus Pinus. It has excellent ornamen- tal values due to many trunks from its root collar, and produces female, male, and bisexual strobili on the same tree. However, there is limited study whether the bisexual strobili are functional, mature lateral cones produce filled seeds, and the seeds from the mature lateral cones germinate and grow as well as those from mature apical cones. The structure of apical female, and lateral male and bisexual strobili were analyzed in an open-pollination-progeny population. The strobili were photographed to obtain external, cross-section, and radial-section images using a 45× stereoscopic microscope. Radial sections of strobili were imaged using scanning electron microscopy. Characteristics of apical and lateral cones and seeds were surveyed by cone analysis and germination test. P. densiflora f. multicaulis developed typical female strobili apically, and ordinary male and bisexual strobili laterally. Additionally, female strobili developed laterally whereas the male strobili were normally located. The mature lateral female strobili had the same structure as the apical female. In the mature bisexual strobili, the proportion of male and female tissue was unequal. The cones developed from lateral female strobili showed highly significant differences in the length, width, and weight, being shorter (32.7%), narrower (26.9%), and lighter (59.8%) than those from apical female strobili. Both types produced filled seeds and seedlings, and well significant positive correlations were found among characteristics of seeds from apical and lateral female strobili. The initial seed germination rate of the seeds from apical female strobili was higher than that of seeds from lateral female strobili, but the difference decreased over time. The viability and spatial distribution of the female and male tissue of bisporangiate cones, and their frequent occurrence suggests a common mechanism for the production of bisporangiate structures in seed plants.
    Źródło:
    Dendrobiology; 2021, 85; 51-59
    1641-1307
    Pojawia się w:
    Dendrobiology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Surface Modification of Self-Consolidated Microporous Ti Implant Compacts Fabricated by Electro-Discharge-Sintering in Air
    Autorzy:
    Jo, Y. J.
    Yoon, Y. H.
    Kim, Y. H.
    Chang, S. Y.
    Kim, J. Y.
    Lee, Y. K.
    Van Tyne, C. J.
    Lee, W. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/356790.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    titanium
    implant
    porous
    sintering
    X-ray photoelectron spectroscopy (XPS)
    Opis:
    A single pulse of 0.75-2.0 kJ/0.7g of atomized spherical Ti powders from 300 mF capacitor was applied to produce a microporous Ti implant compact by electro-discharge-sintering (EDS). A solid core in the middle of the compact surrounded by a microporous layer was found. X-ray photoelectron spectroscopy was employed to study the surface characteristics of the EDS Ti compact and it revealed that Ti, C and O were the main constituents on the surface with a smaller amount of N. The surface was lightly oxidized and was primarily in the form of TiO2 resulting from the air oxidation during EDS processing. The lightly oxidized surface of the EDS compact also exhibited Ti nitrides such as TiN and TiON, which revealed that the reaction between air constituents and the Ti powders even in times as short as 128 msec.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1287-1291
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    High-temperature Oxidation Behavior and Kinetics of Forged 12Cr-MoVW Steel
    Autorzy:
    Kim, Y. H.
    Oak, J.-J.
    Bae, K.-C.
    Lee, W-J.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/351450.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ferritic/martensitic stainless steels
    forging
    oxidation kinetics
    oxide layer
    Opis:
    The oxidation kinetics of forged 12Cr-MoVW steel was investigated in an air (N2+O2) atmosphere at 873-1073 K (Δ50 K) using thermogravimetric analysis. The oxidized samples were characterized using X-ray diffraction, and the surface and cross-sectional morphologies were examined using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. The forged 12Cr-MoVW steel samples exhibited parabolic behavior and a low oxidation rate compared with their as-cast counterparts. A protective oxide layer was uniformly formed at relatively low temperature (≤973 K) for the forged samples, which thus exhibited better oxidation resistance than the as-cast ones. These oxides are considered solid-solution compounds such as (Fe, Cr)2O3.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1099-1104
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure and Magnetic Properties of NdFeB Sintered Magnets Diffusion-Treated with Cu/Al Mixed Dyco Alloy-Powder
    Autorzy:
    Lee, M.-W.
    Bae, K.-H.
    Lee, S.-R.
    Kim, H.-J.
    Jang, T.-S.
    Powiązania:
    https://bibliotekanauki.pl/articles/353351.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Nd-Fe-B sintered magnets
    grain boundary diffusion process
    low melting point element
    DyCo alloy-powder diffusion
    Opis:
    We investigated the microstructural and magnetic property changes of DyCo, Cu + DyCo, and Al + DyCo diffusion-treated NdFeB sintered magnets. The coercivity of all diffusion treated magnet was increased at 880ºC of 1st post annealing(PA), by 6.1 kOe in Cu and 7.0 kOe in Al mixed DyCo coated magnets, whereas this increment was found to be relatively low (3.9 kOe) in the magnet coated with DyCo only. The diffusivity and diffusion depth of Dy were increased in those magnets which were treated with Cu or Al mixed DyCo, mainly due to comparatively easy diffusion path provided by Cu and Al because of their solubility with Ndrich grain boundary phase. The formation of Cu/Al-rich grain boundary phase might have enhanced the diffusivity of Dy-atoms. Moreover, relatively a large number of Dy atoms reached into the magnet and mostly segregated at the interface of Nd2 Fe14 B and grain boundary phases covering Nd2 Fe14 B grains so that the core-shell type structures were developed. The formation of highly anisotropic (Nd, Dy)2Fe14B phase layer, which acted as the shell in the core-shell type structure so as to prevent the reverse domain movement, was the cause of enhancing the coercivity of diffusion treated NdFeB magnets. Segregation of cobalt in Nd-rich TJP followed by the formation of Co-rich phase was beneficial for the coercivity enhancement, resulting in the stabilization of the metastable c-Nd2O3 phase.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1263-1266
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of High-Strength Gray Cast Iron Using Permanent Magnet Scrap
    Autorzy:
    Park, S.-Y.
    Kim, J. H.
    Seo, S. J.
    On, J. S.
    Lim, K. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/352204.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    gray cast iron
    rare earth element
    Nd-Fe-B magnet scrap
    graphite formation
    microstructure
    Opis:
    In this study, we have developed the manufacturing technology for high strength gray cast irons by using the spent permanent magnet scraps. The cast specimen inoculated by using a spent magnet scraps showed the excellent tensile strength up to 306MPa. This tensile strength value is 50MPa higher than that of the specimen cast without inoculation, and is similar to that of the specimen inoculated by using the expensive misch-metal. These superior mechanical properties are attributed to complex sulfides created during solidification that promote the formation and growth of Type-A graphite. It is therefore concluded that spent magnets scrap can provide an efficient and cost-effective inoculation agent for the fabrication of high-performance gray cast iron.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1113-1117
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Carbon Co-Deposition During Gas Reduction of Water-Atomized Fe-Cr-Mo Powder
    Autorzy:
    Ali, B.
    Choi, S. H.
    Seo, S. J.
    Maeng, D. Y.
    Lee, C. G.
    Kim, T. S.
    Park, K. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/352709.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    water atomization
    Fe-based powder
    oxide reduction
    powder metallurgy
    sinter-hardening alloys
    Opis:
    The water atomization of iron powder with a composition of Fe-3Cr-0.5Mo (wt.%) at 1600°C and 150 bar creates an oxide layer, which in this study was reduced using a mixture of methane (CH4) and argon (Ar) gas. The lowest oxygen content was achieved with a 100 cc/min flow rate of CH4, but this also resulted in a co-deposition of carbon due to the cracking of CH4. This carbon can be used directly to create high-quality, sinter hardenable steel, thereby eliminating the need for an additional mixing step prior to sintering. An exponential relationship was found to exist between the CH4 gas flow rate and carbon content of the powder, meaning that its composition can be easily controlled to suit a variety of different applications.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1119-1124
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Reaction Kinetics and Morphological Study of TiNb2O7 Synthesized by Solid-State Reaction
    Autorzy:
    Choi, S. H.
    Ali, B.
    Choi, K. S.
    Hyun, S. K.
    Sim, J. J.
    Choi, W. J.
    Joo, W.
    Lim, J. H.
    Lee, T. H.
    Kim, T. S.
    Park, K. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/355326.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    solid state reaction
    kinetic analysis
    quantitative phase analysis
    TiNb2O7 synthesis
    Opis:
    Although TiNb2O7 is regarded as a material with high application potential in lithium-ion batteries (LIBs) and solid-oxide fuel cells (SOFCs), it has been difficult to find suitable cost-effective conditions for synthesizing it on a commercial scale. In this study, TiNb2O7 compounds were synthesized by a solid state synthesis process. For stoichiometrically precise synthesis of the TiNb2O7 phase, the starting materials, TiO2 and Nb2O5 were taken in a 1:1 molar ratio. Activation energy and reaction kinetics of the system were investigated at various synthesis temperatures (800,1000,1200, and 1400°C) and for various holding durations (1,5,10, and 20 h). Furthermore, change in the product morphology and particle size distribution were also evaluated as a function of synthesis temperature and duration. Additionally, quantitative phase analysis was conducted using the Rietveld refinement method. It was found that increases in the synthesis temperature and holding time lead to increase in the mean particle size from 1 to 4.5 μm. The reaction rate constant for the synthesis reaction was also calculated.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1051-1056
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization Of The Graded Microstructure In Powder Sintered Porous Titanium
    Charakterystyka gradientowej mikrostruktury porowatego tytanu spiekanego z proszku
    Autorzy:
    Oak, J.-J.
    Bang, J. I.
    Bae, K.-C.
    Kim, Y. H.
    Lee, Y. C.
    Chun, H. H.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/356239.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    titanium
    powder metallurgy
    porous structure
    sintering
    biomaterial
    tytan
    metalurgia proszków
    struktura porowata
    spiekanie
    biomateriał
    Opis:
    The proposed sintering process produce porosity and functional graded microstructure in the sinterd titanium powders. Titanium powders with different micro sizes were sintered at the proposed temperature region at 1200 and 1300°C for 2h. The apatite-forming on the graded microstructure is observed by immersion test in Hanks balanced salt soluion at 37°C. Sintering condition of titanium powders is estimated by thermogravitmetry-differential thermal analysis (TG-DTA). The synthersied surface structures and apatite-forming ability were characterized by a field emission scanning electron microscopy (FE-SEM) observation and energy dispersive X-ray spectroscopy (EDS) analysis. As results, these graded microstructure of sintered porous titanium powders reveals apatite-forming ability as osseointegration by calcification in Hanks balanced salt soluion(HBSS) at 37°C.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1265-1269
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of a Spherical Titanium Powder by Combined Combustion Synthesis and DC Plasma Treatment
    Autorzy:
    Choi, S. H.
    Ali, B.
    Hyun, S. K.
    Sim, J. J.
    Choi, W. J.
    Joo, W.
    Lim, J. H.
    Lee, Y. J.
    Kim, T. S.
    Park, K. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/356067.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    combustion synthesis
    DC plasma treatment
    titanium powder
    3D printing process
    combustion parameters
    Opis:
    Combustion synthesis is capable of producing many types of refractory and ceramic materials, as well as metals, with a relatively lower cost and shorter time frame than other solid state synthetic techniques. TiO2 with Mg as reductant were dry mixed and hand compacted into a 60 mm diameter mold and then combusted under an Ar atmosphere. Depending on the reaction parameters (Mg concentration 2 ≤ α ≤ 4), the thermocouples registered temperatures between 1160°C and 1710°C . 3 mol of Mg gave the optimum results with combustion temperature (Tc) and combustion velocity (Uc) values of 1372°C and 0.26 cm/s respectively. Furthermore, this ratio also had the lowest oxygen concentration in this study (0.8 wt%). After combustion, DC plasma treatment was carried out to spheroidize the Ti powder for use in 3D printing. The characterization of the final product was performed using X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and N/O analysis.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1057-1062
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Low-velocity impact characteristics of composite plates with shape memory alloy wires
    Niskoprędkościowe charakterystyki uderzeniowe płyt kompozytowych zawierających włókna ze stopów z pamięcią kształtu
    Autorzy:
    Rim, M.-S.
    Kim, E.-H.
    Lee, I.
    Choi, I.-H.
    Ahn, S.-M.
    Koo, K.-N.
    Bae, J.-S.
    Roh, J.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/279293.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
    Tematy:
    shape memory alloy
    SMAHC
    composite
    low-velocity impact
    impact resistance
    Opis:
    To investigate impact characteristics of shape memory alloy hybrid com- posites (SMAHC), several experiments were performed. Tensile tests of shape memory alloy (SMA) wires were carried out to investigate thermomechanical properties, and low-velocity impact tests of SMAHC plates and conventional composite plates without SMAs at the critical energy level. low-velocity impact tests of several types of composite plates, including composite plates with embedded SMAs/Fe/Al wires and conventional composite plates, were also done. Results of these experiments show that embedding SMAs in a composite plate can improve the impact resistance. Lastly, low-velocity impact tests of SMAHC plates with SMA wires embedded at different positions through the thickness were performed in an effort to improve the impact resistance. Embedding SMA wires at a lower position in the composite plates was the most effective for improving the impact resistance.
    Do analizy charakterystyk uderzeniowych hybrydowych kompozytów SMAHC zwierających włókna SMA ze stopów wykazujących efekt pamięci kształtu przeprowadzono szereg badań eksperymentalnych. Przeprowadzono próby na rozciąganie włókien SMA w celu zbadania ich właściwości termomechanicznych oraz niskoprędkościowe testy uderzeniowe płyt SMAHC oraz konwencjonalnych płyt laminowanych przy energii krytycznej. Wykonano także testy dla płyt kompozytowych zawierających włókna SMA/Fe/Al. Rezultaty doświadczeń pokazały, że wbudowanie w strukturę laminatu włókien SMA może zwiększyć odporność kompozytu na obciążenie uderzeniowe. Opisano również badania eksperymentalne płyt SMAHC z włóknami SMA wbudowanymi na różnej głębokości. Wykazano, że najlepsze parametry posiadają kompozyty z włóknami umieszczonymi możliwie daleko od uderzanej powierzchni.
    Źródło:
    Journal of Theoretical and Applied Mechanics; 2011, 49, 3; 841-857
    1429-2955
    Pojawia się w:
    Journal of Theoretical and Applied Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Compositional Dependence of Hardness of Ge-Sb-Se Glass for Molded Lens Applications
    Zależność stężeniowa twardości szkła Ge-Sb-Se do zastosowań na formowane soczewki
    Autorzy:
    Park, J. K.
    Lee, J. H.
    Shin, S. Y.
    Yi, J. H.
    Lee, W. H.
    Park, B. J.
    Choi, J. H.
    Kim, N. Y.
    Choi, Y. G.
    Powiązania:
    https://bibliotekanauki.pl/articles/352228.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    chalcogenide glasses
    Ge-Sb-Se glass
    infrared lens
    molded lens
    infrared camera
    szkło
    Ge-Sb-Se
    soczewki formowane
    twardość szkła
    kamera termowizyjna
    Opis:
    Chalcogenide glass in the ternary Ge-Sb-Se system is inherently moldable, thus being considered as a strong candidate material for use in infrared-transmitting lens applications from the viewpoint of thermal and mechanical stability. In an effort to experimentally determine compositional region suitable for the molded lens applications, we evaluate its compositional dependence of hardness. Among the constituent atoms, Ge content turns out to exert a most conspicuous correlation with hardness. This phenomenological behavior is then explained in connection with the structural evolution that Ge brings about.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1205-1208
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-100 z 100

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies