Informacja

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

Wyszukujesz frazę "Kim, Y. J." wg kryterium: Autor


Tytuł:
Extraction Factor Of Pure Ammonium Paratungstate From Tungsten Scraps
Współczynnik ekstrakcji czystego parawolframianu amonu z odpadów wolframowych
Autorzy:
Pee, J-H.
Kim, G. H.
Lee, H. Y.
Kim, Y. J.
Powiązania:
https://bibliotekanauki.pl/articles/356567.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
raw material
recycling
ammonium paratungstate
tungsten scraps
extraction
surowce
recykling
parawolfrawian amonu
odpady wolframowe
ekstrakcja
Opis:
Typical oxidation process of tungsten scraps was modified by the rotary kiln with oxygen burner to increase the oxidation rate of tungsten scraps. Also to accelerate the solubility of solid oxidized products, the hydrothermal reflux method was adapted. By heating tungsten scraps in rotary kiln with oxygen burner at around 900° for 2hrs, the scraps was oxidized completely. Then oxidized products (WO3 and CoWO4) was fully dissolved in the solution of NaOH by hydrothermal reflux method at 150° for 2hrs. The dissolution rate of oxidized products was increased with increasing the reaction temperature and concentration of NaOH. And then CaWO4 and H2WO4 could be generated from the aqueous sodium tungstate solution. Ammonium paratungstate (APT) also could be produced from tungstic acid using by aqueous ammonium solution. The morphologies (cubic and plate types) of APT was controlled by the stirring process of purified solution of ammonium paratungstate.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1403-1405
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extraction Factor Of Tungsten Sources From Tungsten Scraps By Zinc Decomposition Process
Współczynnik ekstrakcji związków wolframu z odpadów wolframowych w procesie rozkładu cynku
Autorzy:
Pee, J-H.
Kim, G. H.
Lee, H. Y.
Kim, Y. J.
Powiązania:
https://bibliotekanauki.pl/articles/354774.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
raw material
recycling
zinc decomposition process
tungsten carbide
tungstic acid
surowce
recykling
proces rozkładu cynku
węglik wolframu
kwas wolframowy
Opis:
Decomposition promoting factors and extraction process of tungsten carbide and tungstic acid powders in the zinc decomposition process of tungsten scraps which are composed mostly of tungsten carbide and cobalt were evaluated. Zinc volatility was suppressed by the enclosed graphite crucible and zinc volatilization pressure was produced in the reaction graphite crucible inside an electric furnace for ZDP (Zinc Decomposition Process). Decomposition reaction was done for 2hours at 650°, which 100% decomposed the tungsten scraps that were over 30 mm thick. Decomposed scraps were pulverized under 75μm and were composed of tungsten carbide and cobalt identified by the XRD (X-ray Diffraction). To produce the WC(Tungsten Carbide) powder directly from decomposed scraps, pulverized powders were reacted with hydrochloric acid to remove the cobalt binder. Also to produce the tungstic acid, pulverized powders were reacted with aqua regia to remove the cobalt binder and oxidize the tungsten carbide. Tungsten carbide and tungstic acid powders were identified by XRD and chemical composition analysis.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1311-1314
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect Of SiC Particles On Sinterability Of Al-Zn-Mg-Cu P/M Alloy
Wpływ cząstek SiC na spiekalność proszku stopowego Al-Zn-Mg-Cu
Autorzy:
Rudianto, H.
Jang, G. J.
Yang, S. S.
Kim, Y. J.
Dlouhy, I.
Powiązania:
https://bibliotekanauki.pl/articles/351304.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
metal matrix composites
powder metallurgy
sintering
heat treatment
kompozyty metalowe
metalurgia proszków
spiekanie
obróbka cieplna
Opis:
Premix Al-5.5Zn-2.5Mg-0.5Cu alloy powder was analyzed as matrix in this research. Gas atomized powder Al-9Si with 20% volume fraction of SiC particles was used as reinforcement and added into the alloy with varied concentration. Mix powders were compacted by dual action press with compaction pressure of 700 MPa. High volume fraction of SiC particles gave lower green density due to resistance of SiC particles to plastic deformation during compaction process and resulted voids between particles and this might reduce sinterability of this mix powder. Sintering was carried out under ultra high purity nitrogen gas from 565°-580°C for 1 hour. High content of premix Al-5.5Zn-2.5Mg-0.5Cu alloy powder gave better sintering density and reached up to 98% relative. Void between particles, oxide layer on aluminum powder and lower wettability between matrix and reinforcement particles lead to uncompleted liquid phase sintering, and resulted on lower sintering density and mechanical properties on powder with high content of SiC particles. Mix powder with wt90% of Alumix 431D and wt10% of Al-9Si-vf20SiC powder gave higher tensile strength compare to another mix powder for 270 MPa. From chemical compositions, sintering precipitates might form after sintering such as MgZn2, CuAl2 and Mg2Si. X-ray diffraction, DSC-TGA, and SEM were used to characterize these materials.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1383-1385
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
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:
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:
A Study on Discharge Characteristics by Using MF and RF Power in Remote Dielectric Barrier Discharge
Autorzy:
Kim, D.
Shim, Y.
Kim, H.
Han, J.
Powiązania:
https://bibliotekanauki.pl/articles/1398758.pdf
Data publikacji:
2016-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
52.77.Bn
Opis:
We have developed an atmospheric pressure plasma apparatus of remote dielectric barrier discharge (RDBD) applicable for a large area. We have systematically studied the characteristics of medium frequency (MF, 40 kHz) and radio frequency (RF, 13.56 MHz) discharge using an optical emission spectroscope. Nitrogen (N₂) and argon (Ar) gases were used in the MF and RF discharge excitation, respectively, in a mixture with clean dry air (CDA). The peak of oxygen radical (O*₂) appears at 259.3 nm when the RDBD is employed. Furthermore, intensive peaks are observed at gas ratios of N₂:CDA=100:1 in MF excitation and at gas ratios of Ar:CDA=70:0.5 in RF discharge excitation. On the other hand, the contact angle shows about 5° in PET samples after the RDBD treatment using the RF and MF discharge excitation. Surface analyses of polyethylene terephthalate (PET) samples were carried out using an atomic force microscope and X-ray photoelectron spectroscope.
Źródło:
Acta Physica Polonica A; 2016, 129, 4; 707-710
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
User requirements supporting the safe navigation in Korean Coast
Autorzy:
Jeong, J.S.
Jeong, J.
Kim, H.J.
Kim, S. Y.
Powiązania:
https://bibliotekanauki.pl/articles/320412.pdf
Data publikacji:
2013
Wydawca:
Polskie Forum Nawigacyjne
Tematy:
user requirements
user needs
e-navigation
safe navigation
navigational information
Opis:
This research aims at investigating the user requirements at the service level for safe navigation system, following e-navigation strategy implementation plan. The user requirements is surveyed to collect real-time navigational information and then to find out services through the presentation of the collected information. To provide the information on user needs for the system developer, a questionnaire survey has been made. Based on this surveys, this research investigated which navigational information is with higher priority for the safe navigation during ship operation by bridge team in harbour and in coastal and confined.
W artykule przedstawiono wyniki badań wymagań użytkownika związanych z poziomem bezpieczeństwa nawigacji, stosownie do strategii wprowadzania e-nawigacji. Badano oczekiwania użytkowników odnośnie informacji nawigacyjnej dostarczanej w czasie rzeczywistym oraz sposobu jej prezentacji metodą ankietową. Wykonano przegląd kwestionariuszy dla ustalenia informacji o potrzebach użytkownika z myślą o projektantach systemów. Na bazie opisywanych badań ustalono, jakie informacje nawigacyjne cechują się najwyższym priorytetem w opinii użytkowników, zarówno w warunkach żeglugi przybrzeżnej, jak i w porcie lub akwenie ograniczonym.
Źródło:
Annual of Navigation; 2013, 20; 37-48
1640-8632
Pojawia się w:
Annual of Navigation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis And Characterization Of SiO2, SnO2 And TiO2 Metal Oxide Shells Covering Cu2O Particles
Synteza i charakterystyka powłok tlenkowych SiO2, SnO2 i TiO2 pokrywających cząstki Cu2O
Autorzy:
Yu, R.
Yun, J.
Kim, Y.
Powiązania:
https://bibliotekanauki.pl/articles/355566.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cu2O
metal oxide coating
pH value
SiO2
TiO2
SnO2
powłoki tlenkowe
Opis:
In this work is described a means of improving the chemical stability of Cu2O@SiO2, Cu2O@SnO2 and Cu2O@TiO2 materials. The SiO2, SnO2 and TiO2 coated samples were stable from pH 3 to pH 10 for up to seven days. To determine the stability of the coated nanoparticles, and their colloidal solutions under acidic and basic conditions, colloidal nanoparticle solutions with various pH values were prepared and monitored over time. Details of the effect of variations in pH on the phase stability of core-shell type Cu2O were characterized using transmission electron microscopy and X-ray diffraction.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1159-1163
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Characterization of Black CoFe2O4 Pigments Using MOOH (M = Fe and Co) Nanorod
Autorzy:
Yu, R.
Yun, J.
Kim, Y.
Powiązania:
https://bibliotekanauki.pl/articles/355743.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
β-Co/FeOOH
CoFe2O4
black pigment
substitution
solid solution
Opis:
We studied the coloration and phase transformation of various iron based pigment with cobalt substitution method and heat treatment. First, we synthesized well defined one dimension β-Fe/CoOOH nanorods using the solid solution method. Yellowish β-Fe/CoOOH nanorods were transformed into reddish intermediate states and, finally, black CoFe2 O4 pigments was obtained. Divalent cobalt ions easily occupied tetrahedral sites. The prepared pigments were well characterized in terms of physical properties by using UV-vis, CIE Lab color parameter measurements, SEM (scanning electron microscopy) and XRD (powder X-ray diffraction). In addition, the magnetization property of the prepared CoFe2 O4 pigment was confirmed by VSM (vibrating sample magnetometer).
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 2B; 1231-1234
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Study On Fracture Property Of Tapered Double Cantilever Beam Specimen With Aluminum Foam
Doświadczalne badanie pękania mimośrodowo rozciąganej zwężanej próbki z bocznym karbem wykonanej z piany aluminiowej
Autorzy:
Kim, Y. C.
Kim, S. S.
Cho, J. U.
Powiązania:
https://bibliotekanauki.pl/articles/352697.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
aluminum foam
tapered double cantilever beam (TDCB)
fracture behavior
adhesively bonded structures
adhesive fracture energy
piana aluminiowa
pękanie
stożkowa podwójna belka wspornikowa
struktura sklejona
Opis:
It is indispensable to evaluate fracture energy as the bonding strength of adhesive at composite material with aluminum foam. This specimen is designed with tapered double cantilever beam by British standards (BS 7991 and ISO 11343). 4 kinds of specimens due to m values of 2, 2.5, 3 and 3.5 are manufactured and compared each other with the experimental results. Adhesive fracture energy is calculated from the formulae of British standards. The value of m is the gradient which is denoted as the length and the height of specimen. As m becomes greater at static experimental result, the maximum load becomes higher and the displacement becomes lower. And the critical fracture energy becomes higher. As m becomes less at fatigue experimental result, the displacement becomes higher and the critical fracture energy becomes higher. Fracture behavior of adhesive can be analyzed by this study and these experimental results can be applied into real field effectively. The stability on TDCB structure bonded with aluminum foam composite can be predicted by use of this experimental result. Adhesive fracture energy is calculated from the formulae of British standards. Based on correlations obtained in this study, the fracture behavior of bonded material would possibly be analyzed and aluminum foam material bonded with adhesive would be applied to a composite structure in various fields, thereby analyzing the mechanical and fracture characteristic of the material.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1459-1462
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on Effects of Mold Temperature on the Injection Molded Article
Autorzy:
Han, J.-H.
Kim, Y.-C.
Powiązania:
https://bibliotekanauki.pl/articles/351919.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
injection molding
mold temperature
cooling temperature
molded article
Opis:
This is a study of the effects of temperature of injection mold on the injection molded article. By supplying water of the proper temperature in the cooling line of mold in the cooling process, the mold was the appropriate temperature, and the deformation of the injection molded article was examined according to the mold temperature. In this study, we conducted simulation analysis and experiments, and the results were analyzed. The minimum deformation of the injection molded article model obtained by supplying 50°C water in the cooling line is 0.003 mm, and the maximum deformation was 0.813 mm. Injection molded article models obtained by supplying 20°C water were found to be a minimum of 0.002 mm, with deformation of up to 0.761 mm. When comparing both conditions, the error rate of injection molded article obtained by supplying 20°C water in the mold cooling line was lower by about 0.18%.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 2B; 1271-1274
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
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:
Investigation of Localized Electric Field in the Type-II InAs/GaAsSb/GaAs Structure
Autorzy:
Lee, S.
Kim, J.
Yoon, S.
Kim, Y.
Honsberg, C.
Powiązania:
https://bibliotekanauki.pl/articles/1398577.pdf
Data publikacji:
2016-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.66.Fd
78.40.-q
73.40.Lq
73.50.Pz
Opis:
The effect of localized electric field (F) was investigated in the type-II InAs/GaAsSb/GaAs structures. To compare type-I to type-II, two types of samples with different Sb contents was grown by molecular beam epitaxy, whose Sb contents are 3% (type-I) and 16% (type-II), respectively. In the both samples, we performed excitation power dependent-photoreflectance at 10 K and the result showed that the period of the Franz-Keldysh oscillation, revealed above the band gap $(E_{g})$ of GaAs, was broadened in the only type-II system, which means that F was also increased because it is proportional to the period of the Franz-Keldysh oscillation while the period of the Franz-Keldysh oscillations stayed unchanged in type-I system. This phenomenon is explained by that the F was affected by the band bending effect caused by the spatially separated photo-excited carriers in the interface between GaAsSb and GaAs. The F changed linearly as a function of square root of excitation power as expected for the F. Moreover, F was calculated using fast Fourier transform method for a qualitative analysis, which is in a good agreement with the theory of triangular well approximation.
Źródło:
Acta Physica Polonica A; 2016, 130, 5; 1213-1216
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of InAs Coverage on Transition of Size Distribution and Optical Properties of InAs Quantum Dots
Autorzy:
Kim, G.
Jeon, S.
Cho, M.
Choi, H.
Kim, D.
Kim, M.
Kwon, Y.
Choe, J.
Kim, J.
Leem, J.
Powiązania:
https://bibliotekanauki.pl/articles/1535820.pdf
Data publikacji:
2010-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.15.Hi
68.37.Ps
78.55.Cr
78.67.Hc
Opis:
The influence of InAs coverage on the formation of self-assembled quantum dots grown by molecular-beam epitaxy was investigated by atomic force microscopy and photoluminescence measurements. As the InAs coverage increased from 2.0 to 3.0 monolayers, the quantum dot density decreased from 1.1 × $10^{11}$ to 1.36 × $10^{10} cm^{-2}$. This result could be attributed to the coalescence of neighboring small InAs quantum dots resulting in the formation of much larger InAs quantum dots with lower quantum dot density. Atomic force microscopy results revealed that as the InAs quantum dot coverage increased, the transition of size distribution of InAs quantum dots from single-modal to multimodal occurred. The temperature-dependent photoluminescence spectra showed that the photoluminescence spectra red shifted and the photoluminescence peak intensity decreased as the InAs coverage increased. The thermal activation energy was strongly dependent on the InAs coverage, and for InAs quantum dots with 3.0 ML thick InAs coverage, this energy was estimated to be 147 meV.
Źródło:
Acta Physica Polonica A; 2010, 118, 4; 673-676
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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