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Tytuł:
Energy and financial balance of heat pump application (outdoor air-water) in a family house
Energetyczne i ekonomiczne uwarunkowania zastosowania pomp ciepła (powietrze-woda) w budynkach mieszkalnych
Autorzy:
Knizova, K.
Kovac, M.
Powiązania:
https://bibliotekanauki.pl/articles/2065195.pdf
Data publikacji:
2013
Wydawca:
Politechnika Częstochowska
Tematy:
heat pump
energy
financial balance
payback period
family house
pompy ciepła
bilans energetyczny i ekonomiczny
czas zwrotu nakładów
budynki mieszkalne
Opis:
The content of the article is elaboration of tabular analysis of heat pump “outdoor air-water“ in heating and domestic hot water system in family house. The object of analysis is comparison of conventional system with using gas boiler or electric boiler and application of heat pump “outdoor air-water“. The part of analysis is energy performance of renewable energy source application as well as financial balance of savings in relation to conventional heat sources and pay-back period of investment in heat pump. Pay-back periods are determined for given boundary conditions and they were considered with rise in the price of energy too.
Tematem artykułu jest analiza zastosowania pompy ciepła powietrze-woda do ogrzewania i przygotowania ciepłej wody użytkowej w budynku mieszkalnym. Przedmiotem analizy jest porównanie konwencjonalnego systemu z wykorzystaniem kotła gazowego lub elektrycznego i niekonwencjonalnego z zastosowaniem pompy ciepła powietrze-woda. Częścią przedstawionej analizy jest wyznaczenie energetycznych i ekonomicznych korzyści z zastosowania odnawialnych źródeł energii w stosunku do źródeł konwencjonalnych oraz okresu zwrotu nakładów poniesionych na tego typu inwestycję. Okres amortyzacji ustalono dla podanych warunków brzegowych z uwzględnione z wzrostem cen energii.
Źródło:
Budownictwo o Zoptymalizowanym Potencjale Energetycznym; 2013, 2 (12); 40--46
2299-8535
2544-963X
Pojawia się w:
Budownictwo o Zoptymalizowanym Potencjale Energetycznym
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza oddziaływania między pojazdem a nawierzchnią dla celów klasyfikacji IRI w ramach słowackiego PMS
An analysis of vehicle-road surface interaction for classifi cation of IRI in the frame of Slovak PMS
Autorzy:
Celko, J.
Decky, M.
Kovac, M.
Powiązania:
https://bibliotekanauki.pl/articles/301414.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
stan drogi
nawierzchnia
równość
bezpieczeństwo
droga
niedogodności
road serviceability
pavement
evenness
road safety
discomfort
Opis:
Równość jest jednym z podstawowych czynników jakości nawierzchni. Stanowi ona charakterystykę stanu drogi, jak również bezpieczeństwa na drodze i komfortu jazdy. Nierówności podłużne powodują niedogodności w ruchu drogowym i niebezpieczeństwo zmniejszenia oddziaływania między kołami a nawierzchnią. Wymienione aspekty zostały wzięte pod uwagę w analizie poziomów klasyfikacji w ramach Słowackiego PMS. Symulacje różnych warunków brzegowych podczas diagnostyki nawierzchni miały na celu przede wszystkim zbadanie wpływu nierówności na pojazd, a co za tym idzie, na komfort jazdy. Z drugiej strony, wpływ nierówności na oddziaływanie między nawierzchnią a kołem stanowił podstawowe kryterium oceny z punktu widzenia bezpieczeństwa. Przedmiotem artykułu jest obserwacja i ocena opisanych parametrów podczas przeprowadzonych symulacji i pomiarów eksperymentalnych. Do symulacji użyto dynamicznych charakterystyk prawdziwych pojazdów.
Road evenness is one from basic factors of the pavement quality. It represents the characteristic of the road serviceability but also road safety and comfortable. The longitudinal unevenness causes the traffi c discomfort and danger of the wheel-pavement interaction decreasing. Listed aspects were taken into account for analyze of classifi cation levels in frame of the Slovak PMS. The simulations of different boundary conditions during pavement surface diagnostics were oriented above all to the response of unevenness to the vehicle and to the ride comfort consequently. On the other hand an effect of unevenness to interaction between surface and wheel was the basic criteria of evaluation from safety point of view. The paper is oriented to the observation and evaluation described parameters during realized simulations and experimental measurements. For simulations were used dynamic characteristics of real vehicles.
Źródło:
Eksploatacja i Niezawodność; 2009, 1; 15-21
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Injuries Among Slovenian Physical Education Teachers: A Cross-Sectional Study
Autorzy:
Kovac, M.
Leskosek, B.
Hadzic, V.
Jurak, G.
Powiązania:
https://bibliotekanauki.pl/articles/90197.pdf
Data publikacji:
2013
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
occupational health
injuries
physical educators
age
gender
teaching level
uraz
wiek
różnice związane z płcią
zdrowie zawodowe
płeć
edukacja fizyczna
Opis:
A cross-sectional study was carried out to examine the frequency and types of serious injuries in physical educators throughout their professional career, in relation to their gender, age and teaching level, certain factors causing the injuries and the consequences of those injuries on their working ability. The subjects (n = 468) answered a self-administered questionnaire. In men, one group's higher frequency of injuries was 1.8 (95% CI [1.26, 2.57]) times higher than in women. Every year in age increased the odds for moving into a group with a higher frequency of injuries by 7.6% (95% CI [1.06, 1.10]). The most common injuries for both genders were lower limb injuries. The most common cause of injury was the teacher's own mistake. Over 60% of teachers had to modify their teaching after an injury. It is necessary to further explore preventive strategies to reduce injuries in these workers.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2013, 19, 1; 87-95
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Casting and Solidification of Slab Ingot from Tool Steel Using Numerical Modelling
Modelowanie numeryczne odlewania i krzepnięcia wlewków stalowych ze stali narzędziowej
Autorzy:
Tkadlečková, M.
Michalek, K.
Machovčák, P.
Kováč, M.
Socha, L.
Powiązania:
https://bibliotekanauki.pl/articles/356253.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steel
slab ingot
macrosegregation
cracks
modelling
stal
wlewki stalowe
segregacja
pęknięcia
modelowanie
Opis:
The main problem in the production of forgings from tool steels, especially thick plates, blocks, pulleys and rods which are used for special machine components for demanding applications, it is the inhomogeneous structure with segregations, cracks in segregations or complex type of non-metallic inclusions MnS and TiCN. These forgings are actually produced from conventional forging ingots. Due to the size of forgings, it would be interesting the production of these forgings from slab ingots. It is possible that the production of forgings from slab ingots (which are distinguished by a characteristic aspect ratio A/B), it would reduce the occurrence of segregations. The paper presents the verification of the production process of slab steel ingots in particular by means of numerical modelling using finite element method. The paper describes the pre-processing, processing and post-processing phases of numerical modelling. The attention was focused on the prediction of behavior of hot metal during the mold filling, on the verification of the final porosity, of the final segregation and on the prediction of risk of cracks depending on the actual geometry of the mold.
Głównym problemem w produkcji odkuwek ze stali narzędziowych, szczególnie grubych płyt, bloków, kół pasowych i prętów, używanych do specjalnych elementów maszyn dla żądanych zastosowań, jest niejednorodna struktura z segregacją, pęknięciami w segregacji lub złożonego typu niemetaliczne wtrącenia MnS i TiCN. Te odkuwki są rzeczywiście produkowane z konwencjonalnych wlewków przeznaczonych do kucia. Ze względu na wielkość odkuwek, można by produkować te odkuwki z wlewków płaskich. Możliwe, że produkcja odkuwki z wlewków płaskich (które wyróżniają się charakterystycznym stosunkiem A/B), pozwoli zmniejszyć występowanie segregacji. W pracy przedstawiono weryfikację procesu produkcji wlewków płaskich za pomocą modelowania numerycznego z wykorzystaniem metody elementów skończonych. Artykuł opisuje fazy modelowania numerycznego: wstępną fazę przetwarzania, obróbkę i przetwarzanie końcowe. Zwrócono uwagę na zachowanie się ciekłego metalu podczas napełniania wlewnic, na weryfikację końcowej porowatości, końcowej segregacji i przewidywania ryzyka pęknięcia w zależności od rzeczywistej geometrii wlewnic.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 4; 2879-2886
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pliocene to Quaternary stress field change in the western part of the Cen tral West ern Carpathians (Slovakia)
Autorzy:
Vojtko, R.
Hók, J.
Kováč, M.
Sliva, L’.
Joniak, P.
Šujan, M.
Powiązania:
https://bibliotekanauki.pl/articles/2060207.pdf
Data publikacji:
2008
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Western Carpathians
fault-slip data
Quaternary stress field
neotectonics
palaeostress analysis
Opis:
Knowledge of the current tectonic regime plays an essential role in natural hazard assessment, especially in the risk assessment of fault activity. Structural analysis of brittle deformations (using in version techniques) was used to determine the stress field state occurring within Pliocene and Quaternary deposits in the western part of the Central Western Carpathians. The deformation pattern of the reduced stress tensor showed that all structural measurements could be separated into two groups. An older, Late Pliocene fault population was activated un der NNW-SSE oriented extension. A younger, Quaternary fault population reflected origin in a NE–SW extensional tectonic regime and it distinctly showed a change the orientation of the S3 of about 70. The change in tectonic activity, as well as in the stress field orientation, is dated to the Pliocene-Pleis to cene boundary. The Quaternary stress field developed dur ing the post-collisional stage of the orogen. Our study shows that the West ern Carpathian internal units document NE-SW to NNE-SSW extension in the broader region around of the north ern Danube Basin.
Źródło:
Geological Quarterly; 2008, 52, 1; 19-19
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Late Miocene fluvial distributary system in the northern Danube Basin (Pannonian Basin System): depositional processes, stratigraphic architecture and controlling factors of the Piešťany Member (Volkovce Formation)
Autorzy:
Šujan, M.
Kováč, M.
Hók, J.
Braucher, R.
Rybár, S.
Leeuw, A. de
Powiązania:
https://bibliotekanauki.pl/articles/2060598.pdf
Data publikacji:
2017
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
fluvial distributary system
facies analysis
sediment supply
accommodation
Pannonian Basin System
late Miocene
Opis:
Aim of the study was to investigate the detailed stratigraphic architecture of the alluvial Volkovce Formation, which was deposited in the northern Danube Basin during the interval between 10 and 6 Ma. Two type locality exposures were subject to facies analysis and interpretation of depositional processes and >500 boreholes served for correlation of spatial variability in the character of the formation. The study was focused on the northern Blatné and western Rišňovce depressions, which are partly separated by the Považský Inovec Mountains horst. It was revealed, that a mostly gravelly fluvial distributary system of the Piešťany Member was deposited in the northern Blatné depression, partly confined by the exposed horst and by incised palaeotopography. The sequence is composed of amalgamated braided river channel bodies with no overbank strata, in response to high sediment supply and low accommodation. The palaeo-stream then crossed the horst in its southern part towards the Rišňovce depression, where there was four times more accommodation. The submerged horst acted as a boundary, where the depositional processes changed to a meandering river and significant overbank deposits started to be preserved. Only small streams were present in the northern Rišňovce depression, which led to very low sediment supply compared to the high accommodation there. The depositional system was affected mainly by the incised palaeotopography, by the location of sediment input together with spatial differences in accommodation rate caused by the activity of the Ripňany Fault on the southeastern side of the Považský Inovec Mts.
Źródło:
Geological Quarterly; 2017, 61, 3; 521--548
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Solidification of Continuously Cast Steel Round Billets Using Numerical Modellin
Autorzy:
Tkadleckova, M.
Válek, L.
Socha, L.
Saternus, M.
Pieprzyca, J.
Merder, T.
Michalek, K.
Kováč, M.
Powiązania:
https://bibliotekanauki.pl/articles/353911.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steel
billet
continuous casting
numerical modelling
metallurgical length
Opis:
The paper is dedicated to the verification of solidification of continuously cast round steel billets using numerical modelling based on the finite element method. The aim of numerical modelling is to optimize the production of continuously cast steel billets of round format. The paper describes the pre-processing, processing and post-processing phases of numerical modelling. Also, the problems with determination of the thermodynamic properties of materials and the heat transfer between the individual parts of the casting system, including the definition of the heat losses along the casting strand in the primary and secondary cooling, were discussed. The first results of numerical simulation show the so-called thermal steady state of continuous casting. The temperature field, the metallurgical length and the thickness of the shell at the end of the mould were predicted. The further research will be concentrated on the prediction the risk of the cracks and the porosity based on the different boundary conditions.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 221-226
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Factor analysis in determining the similarity of local real estate markets’ conditions
Analiza czynnikowa w określaniu podobieństwa uwarunkowań lokalnych rynków nieruchomości
Autorzy:
Bełej, M.
Cellmer, R.
Zrobek, S.
Kovac Subic, M.
Powiązania:
https://bibliotekanauki.pl/articles/37576.pdf
Data publikacji:
2016
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Źródło:
Acta Scientiarum Polonorum. Oeconomia; 2016, 15, 4
1644-0757
Pojawia się w:
Acta Scientiarum Polonorum. Oeconomia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of components of resultant force during face milling
Autorzy:
Sekulić, M.
Kovač, P.
Powiązania:
https://bibliotekanauki.pl/articles/1429406.pdf
Data publikacji:
2008
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
face milling
cutting forces
Opis:
Cutting forces during face milling are investigated intensively analytically and experimentally. Some of previous approaches to cutting forces determination consider only main (tangential) cutting force component, and according to this define cutting power. The experimental investigations were performed during face milling with a goal to determine models of cutting force versus cutter revolution. Different models were determined according to the cutter approach to the workpiece during cutting angle of revolution.
Źródło:
Journal of Machine Engineering; 2008, 8, 2; 65-72
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The internet/intranet application for cutting regime setting
Autorzy:
Kovač, P
Gostimirović, M.
Sekulić, M.
Pižurica, N.
Powiązania:
https://bibliotekanauki.pl/articles/100029.pdf
Data publikacji:
2010
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
optimal cutting regime
MySql data base
internet
Opis:
In the paper Inter for cutting conditions setting during turning is presented. For this task realization MySql data base and program language PHP was used. For this task realization MySql data base and program language PHP was used. This data base is completely free and functions on many operative systems (MS Windows, Linux, FreeBSD ...). Program language PHP has very simple syntax and les experienced users can learn how to use it very quickly As the result of this created was Internet/Intranet application that can be used on Internet also as on own net (Intranet). Application is located on Apache web server.
Źródło:
Journal of Machine Engineering; 2010, 10, 2; 18-24
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Outsourcing in contidions of SMEs : the potential for cost savings
Outsourcing w warunkach małych i średnich przedsiębiorstw : potencjał w zakresie oszczędności kosztowej
Autorzy:
Potkany, M.
Stasiak-Betlejewska, R.
Kovac, R.
Gejdos, M.
Powiązania:
https://bibliotekanauki.pl/articles/405555.pdf
Data publikacji:
2016
Wydawca:
Politechnika Częstochowska
Tematy:
outsourcing
cost savings
enterprise
SME
allocation base
oszczędności kosztowe
przedsiębiorstwo
podstawa alokacji
Opis:
Many enterprises face the issue with increasing own overhead cost and take an effort to reduce it, what is a base for using of outsourcing principles. Outsourcing is primarily used as a strategic tool for corporate resources optimizing. Enterprises decide to remove some supporting activities to external units, which can be provided with ensuring a higher quality and lower costs. These decisions result in increasing attention to a core business orientation and costs reduction. The main purpose of the paper is the cost savings quantification, what is supported by the research results focused on the use and the possibilities of outsourcing in Slovakian SMEs. There was proposed a general model for an economic efficiency evaluation for potential use of the outsourcing through determination of expected costs savings as a result of the research study.
Wiele przedsiębiorstw napotyka na problemy dotyczące wzrastających kosztów własnych i podejmuje wysiłek na rzecz ich redukcji, co stanowi podstawę do zastosowania zasad outsourcingu w przedsiębiorstwie. Outsourcing jest wykorzystywany przede wszystkim, jako strategiczne narzędzie optymalizacji zasobów korporacyjnych. Przedsiębiorstwa decydują się na wyłączenie niektórych obszarów pomocniczych do prowadzenia przez jednostki zewnętrzne, które mogą być świadczone przy zapewnieniu wysokiej jakości niskich kosztach. Decyzje te skutkują zwiększoną uwagą na podstawowej orientacji biznesowej oraz redukcją kosztów. Głównym celem pracy jest identyfikacja oszczędności kosztowych, co poparto wynikami badań ukierunkowanych na wykorzystanie i możliwości outsourcingu w słowackim sektorze MŚP. Zaproponowano ogólny model oceny efektywności ekonomicznej dla potencjalnego wykorzystania outsourcingu poprzez wyznaczane spodziewanych oszczędności kosztowych, jako rezultat pracy badawczej.
Źródło:
Polish Journal of Management Studies; 2016, 13, 1; 145-156
2081-7452
Pojawia się w:
Polish Journal of Management Studies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Laser Scribing on Soft Magnetic Properties of Conventional Grain-Oriented Silicon Steel
Autorzy:
Petryshynets, I.
Puchý, V.
Kováč, F.
Šebek, M.
Powiązania:
https://bibliotekanauki.pl/articles/1032233.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.-y
79.20.Eb
68.55.jm
77.80.Dj
75.50.Vv
Opis:
The present work investigates the influence of laser scribing of grain-oriented silicon steel on the improvement of its soft magnetic properties via magnetic domains modification. The experimental material was represented by conventional Fe-3%Si grain-oriented electrical steel that was taken directly from industrial line after the final box annealing. The laser scribing treatments were applied onto the material surface in order to induce thermal stresses having crucial influence on the magnetic domains refinement. The laser scribing conditions have been optimized by introducing thermal stresses onto the experimental material surface leading to optimal refinement of final domains structures and desired magnetic softness minimization. A semiquantitative relationship has been found between the domain patterns and the used fiber laser treating method. The obtained modified domain structure led to a significant decrease in coercivity measured in DC magnetic field from 20 A/m to 12 A/m.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 777-779
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
$[FeCl_{4}]¯$ Ionic Liquid Based Ferrofluids
Autorzy:
Parnica, J.
Kesa, P.
Kovac, J.
Timko, M.
Antalik, M.
Powiązania:
https://bibliotekanauki.pl/articles/1368745.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.64.kp
75.50.Bb
47.65.Cb
75.50.Mm
Opis:
Magnetic ionic liquids derived from hydrochloride methyl ester alanine amino acids (AA) and $FeCl_{3}$ were synthesized in ethanol and their magnetic properties were investigated. Iron (III) chloride forms ionic liquid in ethanol at saturated concentrations by the transfer of Cl¯ anion from one molecule of $FeCl_{3}$ to the other molecule with the creation of tetrachloro ferrate anion $[FeCl_{4}]$¯ as well as dimer $[Fe_{2}Cl_{7}]$¯. Raman scattering indicates that after addition of hydrochloride methyl ester alanine to ethanol solutions of $FeCl_{3}$ increase the intensities of signal at the frequencies at 318 $cm^{-1}$ and 380 $cm^{-1}$ as markers for the presence of $[FeCl_{4}]$¯ and $[Fe_{2}Cl_{7}]$¯ complexes. The magnetization at room temperature showed in both samples a linear dependence on the applied magnetic field. On the other hand, in the Raman scattering experiments the magnetization is smaller for $FeCl_{3}$ sample in the presence of methyl ester alanine.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 276-277
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Clean bulk YBaCuO superconductors doped by paramagnetic ions of Sm and Yb
Autorzy:
Jirsa, M.
Volochová, D.
Kováč, J.
Diko, P.
Powiązania:
https://bibliotekanauki.pl/articles/1054700.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Ha
74.25.Op
74.25.Sv
74.60.Ge
74.72.-h
Opis:
The recently developed clean cuprate technology was employed to study the effect of tiny amounts of paramagnetic Yb and Sm ions on electromagnetic properties of bulk YBaCuO. Small samples of about 1.5×1.5×0.5 mm³ were measured by vibrating sample magnetometer in the field range ±9 T and temperatures 30 K to 10 K in the non-superconducting tetragonal state and 300 K to 70 K in the orthorhombic, superconducting state. In the latter case, we observed the reversible paramagnetic moment above T_{C}, similar as in the tetragonal state. Below T_{C} an irreversible magnetic moment was observed from which critical current density, J_c, was evaluated using the extended Bean model. The effect of doping by Yb and Sm ions on J_c was studied and a correlation between J_c and the total paramagnetic moment was found. Both J_c(B) and the normalized pinning force density as a function of the reduced magnetic field were analyzed in terms of the classical model and discussed with respect to the material anisotropy, giving us at least a rough idea on the type of the effective pinning type and mechanism.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 1027-1029
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the statistical control of the production processes in organisation
Zastosowanie statystycznej kontroli w zakresie procesów produkcyjnych w organizacji
Autorzy:
Žarnovský, J.
Drlička, R.
Kováč, I.
Petruš, M.
Powiązania:
https://bibliotekanauki.pl/articles/409896.pdf
Data publikacji:
2014
Wydawca:
STE GROUP
Tematy:
statistical process control
production organization
regulation processes
process capability
statistical control
control chart
statystyczna kontrola procesu
organizacja produkcji
procesy regulacyjne
zdolności procesu
kontrola statystyczna
wykres sterowania
Opis:
All recent experiences confirm the fact that the main tasks of quality management are guaranteed only with the high skilled employees. Employees are responsible for the production plan and development, services and processes. The series of standards called ISO 9000 help to establish quality management in organization. Usage of the quality management with statistical process control is also very important for the company. Companies are spending all human, material and financial resources to improve quality management. The objective of the paper is to outline the statistical process control in production company Finalcast Ltd. Žiar nad Hronom.
Wszystkie ostatnie doświadczenia potwierdzają fakt, że główne zadania zarządzania jakością są gwarantowane tylko z wysoko wykwalifikowanymi pracownikami. Pracownicy są odpowiedzialni za plan produkcji i rozwoju, usług i procesów. Seria norm ISO 9000 jest pomocna w celu ustalenia zarządzania jakością w organizacji. Korzystanie w zarządzaniu jakością ze statystycznej kontroli procesu jest również bardzo ważne dla firmy. Firmy wykorzystują wszystkie zasoby ludzkie, materialne i finansowe w celu poprawy jakości zarządzania. Celem pracy jest określenie statystycznego sterowania procesem w produkcji firmy Finalcast Ltd. Žiar nad Hronom.
Źródło:
Management Systems in Production Engineering; 2014, 3 (15); 135-139
2299-0461
Pojawia się w:
Management Systems in Production Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Composites Consisting of High-T$\text{}_{c}$ Superconductor and Fine Magnetic Particles
Autorzy:
Timko, M.
Kopčanský, P.
Kováč, J.
Koneracká, M.
Plecháček, V.
Powiązania:
https://bibliotekanauki.pl/articles/2013009.pdf
Data publikacji:
2000-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.Hs
75.50.Tt
Opis:
The composite systems as a mixture of fine magnetic particles of Fe$\text{}_{3}$O$\text{}_{4}$ and superconducting powder such as Bi$\text{}_{1.8}$Pb$\text{}_{0.2}$Sr$\text{}_{2}$Ca$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{10+x}$ were prepared. The influence of internal magnetic field (generated by magnetic particles) on the superconducting properties of prepared composites were studied as a function of concentration of magnetic particles and their magnetic state. The observed data both of the shielding and the Meissner effect were compared with corresponding linear combination of pure signals of magnetite and superconductor, respectively. The large differences were observed for demagnetized samples. It means that result must be discussed in the frame of the distribution of internal magnetic field created by the magnetic particles.
Źródło:
Acta Physica Polonica A; 2000, 97, 3; 389-392
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of post partum uterine involution on folliculogenesis, oestrus and conception in cows
Wpływ poporodowej inwolucji macicy na folikulogenezę, ruję i zapłodnienie krów
Autorzy:
Zaleha, P.
Vargova, M.
Kadasi, M.
Smitka, P.
Smarzik, M.
Kovac, G.
Powiązania:
https://bibliotekanauki.pl/articles/843770.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Zootechniczne
Opis:
The ending of the puerperium has place when the first oestrus postpartum gestation is restored. To that end the anatomical and histological uterine involution must be completed and the hypothalamic-pituitary-gonadal axis must work properly to allow: oestrus, ovulation, conception, implantation, formation and persistence of corpus luteum of pregnancy. Therefore, early postpartum disorders such as NEB, abnormal gonadotropin secretion, uterine infection and other disorders could have subsequent deleterious effects on oocyte development and competence. However, low BCS coupled with severe NEB during this period suppresses pulsatile LH secretion, reduces ovarian responsiveness to LH stimulation and also reduces the functional competence of the follicle characterized by reduced oestradiol production and ultimately results in delayed ovulation. Normal oestrous cycles in cows coupled with overt signs of oestrus are essential so that insemination can occur at the appropriate time relative to ovulation. Also good nutrition management, environment conditions and welfare can support normal uterine postpartum involution and recurrence of cyclicity.
Okres poporodowy kończy się w momencie wystąpienia pierwszej rui po porodzie. Wcześniej musi się zakończyć anatomiczna i histologiczna inwolucja macicy, a także prawidłowo funkcjonować oś podwzgórzowo-przysadkowo-gonadowa, aby umożliwić ruję, owulację, zapłodnienie, implantację, powstanie i utrzymanie ciążowego ciałka żółtego. Wczesne zaburzenia poporodowe, takie jak ujemny bilans energetyczny (NEB – negative energy balance), anormalna sekrecja gonadotropin, zakażenie macicy i inne zaburzenia mogą mieć szkodliwy wpływ na rozwój i wydolność oocytów. Niska punktowa ocena kondycji krowy (BCS – body condition score) w połączeniu z drastycznym NEB w okresie poporodowym tłumi pulsacyjną sekrecję hormonu luteinizującego (LH – luteinizing hormone), obniża zdolność reakcji jajników na stymulację LH, a także zmniejsza wydolność funkcjonalną pęcherzyków, co charakteryzuje się obniżoną produkcją estradiolu, i wreszcie, powoduje opóźnioną owulację. Normalne cykle rujowe u krów oraz jawne oznaki rui to zasadnicze warunki, aby inseminacja mogła nastąpić we właściwym czasie w stosunku do owulacji. Także dobry system żywienia, prawidłowe warunki środowiskowe i dobrostan zwierząt mogą być czynnikami wspomagającymi normalną poporodową inwolucję macicy i powrót cykliczności rui.
Źródło:
Roczniki Naukowe Polskiego Towarzystwa Zootechnicznego; 2013, 09, 1
1733-7305
Pojawia się w:
Roczniki Naukowe Polskiego Towarzystwa Zootechnicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physical Properties of Magnetite Nanoparticles Covered by 11-Mercaptoundecanoic Acid
Autorzy:
Timko, M.
Kopčanský, P.
Antalik, M.
Simsikova, M.
Valusova, E.
Molcan, M.
Kováč, J.
Powiązania:
https://bibliotekanauki.pl/articles/1429127.pdf
Data publikacji:
2012-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
47.65.Cb
85.70.-w
75.30.Cr
75.47.Lx
Opis:
We have investigated the magnetic behavior of magnetite nanoparticles covered by the 11-mercaptoundecanoic acid around magnetite core prepared by a standard co-precipitation method. The particles show superparamagnetic behavior at room temperature, with transition to a blocked state at blocking temperature 91 K estimated from zero field cooled and field cooled at 500 Oe experiment. The hysteresis loop measured at 293 K showed magnetization 32.8 emu/g at 50 kOe without any coercivity. The mean particle size (7.1 nm) was determined by fitting a magnetization curve obtained at 295 K assuming a log-normal size distribution.
Źródło:
Acta Physica Polonica A; 2012, 121, 5-6; 1321-1323
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Charcoal Supporting Silver as a Water Disinfectant
Autorzy:
Valušová, E.
Antalík, M.
Pristaš, P.
Javorský, P.
Kováč, J.
Timko, M.
Powiązania:
https://bibliotekanauki.pl/articles/1201874.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Ni
75.60.Ej
75.47.Lx
81.05.U-
92.40.qc
Opis:
We investigated the magnetic behavior of charcoal composite with incorporated magnetite and silver ions. The magnetization curve measured at 282 K showed saturation magnetization of 8 emu/g. By benefiting from a mechanical process, the magnetic activated carbon, supporting silver ions (MCAG), acts as a magnetic filter uptaking the bacteria. This idea was confirmed by the DGGE analysis in which the bacterial DNA was detectable in the sediment after the treatment.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 226-227
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation and Complex Characterization of Magnetic Nanoparticles in Magnetic Fluid
Autorzy:
Kubovčíková, M.
Antal, I.
Kováč, J.
Závišová, V.
Koneracká, M.
Kopčanský, P.
Powiązania:
https://bibliotekanauki.pl/articles/1201928.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.75.Fk
78.67.Bf
36.40.Cg
47.65.Cb
75.50.Mm
75.30.Cr
Opis:
This paper deals with the preparation and complex characterization of magnetite nanoparticles (MNPs), stabilized with sodium oleate (SO), by the routine methods such as infrared spectroscopy (FTIR), magnetic measurements, scanning electron microscopy (SEM) and dynamic light scattering (DLS). The FTIR spectra showed that SO molecules were linked to MNPs through chemical bonding. Magnetic measurements proved that the MNPs are superparamagnetic in nature. Four different methods were used to determine the size and size distribution of the MNPs: SEM, DLS, differential centrifugal sedimentation (DCS) and magnetic measurements. SEM analysis showed a relatively narrow size distribution of roughly spherical MNPs with a mean diameter of 61 nm. DLS analysis confirmed monodispersed MNPs production with hydrodynamic diameter of 75 nm. The size distribution determined by DCS was found to be 69 nm. Finally, the calculated magnetic core diameter obtained from magnetization curve was 10 nm. The obtained results demonstrate that SO coated MNPs fulfil the requirements for a useful drug delivery system.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 268-269
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution of Diazinon and Selenium in Various Tissues after Single and Common Intraperitoneal Administration
Dystrybucja diazinonu i selenu w wybranych tkankach po pojedynczym podaniu dootrzewnowym
Autorzy:
Šiška, B.
Toman, R.
Golian, J.
Bošiak, M.
Kovac, S.
Powiązania:
https://bibliotekanauki.pl/articles/388389.pdf
Data publikacji:
2009
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
dianizon
selen
wątroba
nerki
mięśnie
tłuszcz
podanie dootrzewnowe
diazinon
selenium
liver
kidney
muscle
fat
intraperitoneal administration
Opis:
The aim of this study was to evaluate the distribution of diazinon and selenium in various tissues of laboratory rats after single and common intraperitoneal administration. Rats in the age of 135 days were randomly divided into 4 groups. Each group consisted of 10 males. Animals in the first group were administrated with diazinon 20 mg o kg-1 body weight intraperitoneally. Animals in the second group were administrated with selenium (Na2SeO3) 2 mg Se o kg-1 body weight intraperitoneally in physiological solution. Animals in the third group were given a mixture of diazinon 20 mg o kg-1 body weight and selenium 2 mg Se o kg-1 body weight intraperitoneally in physiological solution. The fourth group served as a control group and was administrated only with the physiological solution. 24 hours after the administration of tested substances, animals were sacrificed and samples of livers, kidneys, muscles and fat tissue were taken during the autopsy. The amount of diazinon in tissues was determined using gas chromatography with mass spectrometry. The amount of selenium was determined using atomic absorption spectrometry. We detected significant increase of selenium amount in livers, kidneys and muscles after single selenium administration and also after common administration of both substances. On the other hand we detected significant decrease of selenium amount in muscles and fat tissue after single diazinon administration. We also observed slight accumulation of diazinon amount in samples of kidneys and muscles and significant increase of diazinon in fat tissue after single diazinon administration and also after common administration of both substances.
Celem pracy było określenie dystrybucji dianizonu i selenu w różnych tkankach szczurów laboratoryjnych po pojedynczym dootrzewnowym podaniu. Szczury w wieku 135 dni zostały losowo przyporządkowane do 4 grup. Każda grupa składała się z 10 samców. Zwierzętom z pierwszej grupy podano dootrzewnowo dianizon w dawce 20 mg o kg-1 masy ciała. Zwierzętom drugiej grupy podano dootrzewnowo selen w roztworze fizjologicznym (Na2SeO3) w dawce 2 Se mg o kg-1 masy ciała. Zwierzęta trzeciej grupy otrzymały dootrzewnowo mieszaninę dianizonu (20 mg o kg-1) i selenu (Na2SeO3 - 2 Se mg o kg-1) w roztworze fizjologicznym. Czwartą grupę stanowiły zwierzęta kontrolne, którym podano wyłącznie roztwór fizjologiczny. Po 24 godzinach od podania dianizonu i selenu zwierzęta uśmiercono, po czym pobrano próbki wątroby, nerek, mięśni i tkanki tłuszczowej. Poziom dianizonu w tkankach został zbadany przy użyciu chromatografii gazowej oraz spektrofotometrii masowej. Selen oznaczono metodą spektrofotometrii absorpcji atomowej. Stwierdzono istotny statystycznie wzrost poziomu selenu w wątrobie, nerkach i mięśniach po jednorazowym podaniu selenu, a także po podaniu mieszaniny selenu i dianizonu. Z drugiej strony odnotowano również istotny statystycznie spadek zawartości selenu w mięśniach i tkance tłuszczowej po jednorazowym podaniu dianizonu. Zaobserwowano także niewielki wzrost poziomu dianizonu w nerkach i mięśniach oraz istotny statystycznie wzrost zawartości tego związku w tkance tłuszczowej zarówno po jednorazowym podaniu dianizonu, jak i po podaniu mieszaniny dianizonu i selenu.
Źródło:
Ecological Chemistry and Engineering. A; 2009, 16, 12; 1617-1626
1898-6188
2084-4530
Pojawia się w:
Ecological Chemistry and Engineering. A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Polymer Immobilization on Magnetic Properties of Magnetosomes
Autorzy:
Timko, M.
Džarová, A.
Kovač, J.
Kopčanský, P.
Gojzewski, H.
Powiązania:
https://bibliotekanauki.pl/articles/1535115.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Cr
75.30.Gw
75.50.Mm
75.50.Tt
75.60.Ej
Opis:
The anisotropy of several PVA/magnetosomes magnetically textured films has been investigated from the point of view of magnetic properties. The thin film synthesized under the influence of a magnetic field (99 mT) shows the typical behavior of an anisotropic material. On sample textured in magnetic field the magnetisation loop measurements were performed in dependence on the direction of the external magnetic field with respect to the texture axis. The results of hysteresis measurements show that the magnetic field applied during the synthesis promotes an orientation of the chains of magnetosomes and permanently textured film is obtained after solidification. The obtained values for magnetic remanence and coercivity were dependent on the external magnetic field orientation and the alignment effect of particle moments may be clearly seen which is in agreement with the theoretical model of magnetic particle chains.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 995-997
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Birefringence Study of the Magnetic Core Structure of Ferritin
Autorzy:
Koralewski, M.
Pochylski, M.
Mitróová, Z.
Melníková, L.
Kováč, J.
Timko, M.
Kopčanský, P.
Powiązania:
https://bibliotekanauki.pl/articles/1428622.pdf
Data publikacji:
2012-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.20.Ls
87.15.-v
87.85.jf
Opis:
Magnetically induced optical birefringence (Δ n) was measured for magnetoferritin and horse spleen ferritin aqueous suspensions. The Δ n for magnetoferritin was described in the frame of the Langevin formalism taking into account distribution of core diameter. The established average magnetic dipole moment and core diameter is equal to about 460 $μ_{B}$ and 3 nm, respectively. It was shown that magnetic birefringence and the Cotton-Mouton constant can be powerful parameters in identification of the magnetic core structure of ferritin, especially useful in biomedicine.
Źródło:
Acta Physica Polonica A; 2012, 121, 5-6; 1237-1239
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structure and Transport Properties of La$\text{}_{0.75-x}$RE$\text{}_{x}$Ca$\text{}_{0.25}$MnO$\text{}_{3}$ (RE = Gd, Dy, Ho; 0≤ x≤0.75) Manganites
Autorzy:
Drozd, V.
Pękała, M.
Kovac, J.
Skorvanek, I.
Szymański, M.
Nedilko, S.
Powiązania:
https://bibliotekanauki.pl/articles/2041482.pdf
Data publikacji:
2004-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Lx
71.38.-k
72.20.Ee
75.50.Dd
Opis:
Structure and transport properties have been studied for a series of La$\text{}_{0.75-x}$RE$\text{}_{x}$Ca$\text{}_{0.25}$MnO$\text{}_{3}$ manganites with heavy rare earth ions of Gd, Dy, Ho substituting La with x=0, 0.10, 0.25, 0.50, and 0.75. Polycrystalline samples were prepared by the carbonate precipitation route. The oxygen content was determined by the iodometric titration. The X-ray investigations carried out by the powder method show that the unit cell volume gradually decreases and orthorhombic distortion of the lattice increases with rising RE content. Below the room temperature the electrical resistivity is of the semiconducting type for all the samples studied. Electrical resistivity vs. temperature dependences were analyzed within different models: simple thermal activation, Mott's variable range hopping, adiabatic, nonadiabatic, and bipolaron. The Curie temperatures of Gd, Dy, and Ho substituted manganites determined from magnetization measurements show that at 280 K all the samples are in the paramagnetic phase. The increasing RE fraction reduces magnetization at 4 K as compared to La$\text{}_{0.75}$Ca$\text{}_{0.25}$MnO$\text{}_{3}$.
Źródło:
Acta Physica Polonica A; 2004, 106, 5; 751-758
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation and Investigations of $Ni_{0.2}Zn_{0.8}Fe_2O_4$ Ferrite Nanofiber Membranes by Needleless Electrospinning Method
Autorzy:
Streckova, M.
Mudra, E.
Sebek, M.
Sopcak, T.
Dusza, J.
Kovac, J.
Powiązania:
https://bibliotekanauki.pl/articles/1398266.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.75.Cd
75.50.Gg
81.07.-b
75.47.Lx
Opis:
The preparation of $Ni_{0.2}Zn_{0.8}Fe_2O_4$ nanofiber membranes by simple and versatile needleless electrospinning technique is presented. The single phase of spinel ferrite membrane was obtained after conventional thermal treatment of polyvinyl alcohol (PVA)/metal nitrate precursors at 800°C for 4 h in air. The formation of single-phase fibers was characterized using differential scanning calorimetry accompanied with thermogravimetric analysis. The surface morphology, microstructure and crystal structure were investigated by scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The magnetic properties of the fibrous samples measured in the temperature range from 2 to 300 K verify a soft magnetic behavior, which is quite typical for ferrimagnetic spinel-type ferrites.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 729-731
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of Thorium Ferricyanide
Autorzy:
Göbl, R.
Zentková, M.
Kavečanský, V.
Kováč, J.
Zentko, A.
Powiązania:
https://bibliotekanauki.pl/articles/2013694.pdf
Data publikacji:
2000-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Cr
Opis:
The magnetic properties of Th$\text{}_{3}$[Fe(CN)$\text{}_{6}$]·10H$\text{}_{2}$O were investigated. It was shown that this compound is antiferromagnetically ordered in the low temperature region. The observed antiferromagnetic ordering is stable only in the low field.
Źródło:
Acta Physica Polonica A; 2000, 97, 5; 835-838
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Losses Evolution of Ferritic Fe-Si Steel Subjected to Temper Rolling at Elevated Temperature
Autorzy:
Petryshynets, I.
Kováč, F.
Falat, L.
Puchý, V.
Šebek, M.
Powiązania:
https://bibliotekanauki.pl/articles/1030935.pdf
Data publikacji:
2018-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.-y
75.50.Vv
81.40.Ef
61.72.Cc
Opis:
The effects of heat transport phenomena and deformation gradient through the sheet cross-section on the microstructure, texture and magnetic properties of non-oriented Fe-Si steel were investigated. In order to achieve desired conditions for the steel microstructural and textural parameters improvement, a temper rolling process at elevated temperature was examined in combination with subsequent short term annealing, employing fast heating rate in laboratory conditions. The experimental material was represented by conventional medium silicon, vacuum degassed non-oriented steel that was taken directly from industrial line after final annealing. Performed electron back scattered diffraction measurements revealed that the experimental steel, treated by our proposed thermomechanical treatment, was characterized by coarse-grained microstructure with enhanced intensity of rotating cube texture. The magnetic losses of experimental samples were measured in ac magnetic field with 50 Hz frequency on the toroid with external and internal diameters of 25 mm and 15 mm, respectively. These measurements with magnetic field intensity of 2500 A/m showed that the application of our suggested treatment led to clear power losses reduction of the investigated material from initial 9.9 W/kg to 6.4 W/kg, i.e. by more than 35%.
Źródło:
Acta Physica Polonica A; 2018, 133, 4; 1065-1068
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of Fe@Pt Nanoparticles with Core/Shell Morphology
Autorzy:
Zeleňáková, A.
Zeleňák, V.
Bednarčík, J.
Lauda, M.
Kováč, J.
Powiązania:
https://bibliotekanauki.pl/articles/1535141.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.75.Fk
75.50.Vv
75.40.Gb
Opis:
We have investigated the magnetic properties of iron nanoparticles coated by platinum shell prepared by chemical procedure. Magnetic measurements using SQUID magnetometer confirm the behaviour typical for a superparamagnetic system. From the M(H) loop at 300 K the magnetic moment of each particle $m_{P}$ ≈ $250 μ_{B}$ was calculated. The magnetic relaxation study by the in-phase χ' and out-of-phase χ" ac susceptibilities in frequency range 0.1-1000 Hz suggests the existence of two magnetic layers with different magnetic spin's dynamics and strong dipolar interactions between nanoparticles. The observed magnetic behaviour is caused by the blocking process of interacting superparamagnetic particles with magnetic iron core, diamagnetic platinum shell and spin-glass like behaviour magnetic interlayer between them.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 1002-1004
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Characterization of Magnetoferritin
Autorzy:
Mitróová, Z.
Melníková, L.
Kováč, J.
Timko, M.
Kopčanský, P.
Powiązania:
https://bibliotekanauki.pl/articles/1429123.pdf
Data publikacji:
2012-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Cr
75.50.Ee
75.60.Ej
75.50.Tt
Opis:
The paper presents detailed experimental study of synthesis and characterization a bioinorganic magnetic molecule - magnetoferritin. Magnetoferritin with loading of iron ions per protein molecule in the range from 300 to 3000 was prepared. Size distribution analysis (transmission electron microscopy, dynamic light scattering) shows spherical nanoparticles with particle size distribution from 2 to 12 nm, and hydrodynamic diameter from 12 to 25 nm. The thermomagnetic curves measured after cooling the sample in zero field (zero-field cooling) and under the presence of the measurement field (field cooling) show superparamagnetic behavior with the blocking temperature $T_{b}$ from 22 to 60 K and the magnetization loops measured below $T_{b}$ (at 2 K) show the hysteresis with coercive field from 20 to 30 kA/m depending on the concentration of the magnetic nanoparticles.
Źródło:
Acta Physica Polonica A; 2012, 121, 5-6; 1318-1320
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of Milled and Thermal Relaxed YBa$\text{}_{2}$ (Cu$\text{}_{1-x}$Fe$\text{}_{x}$)$\text{}_{3}$O$\text{}_{y}$
Autorzy:
Timko, M.
Kováč, J.
Sargánková, I.
Zentková, M.
Mihalik, M.
Maťaš, S.
Čiasnohová, A.
Powiązania:
https://bibliotekanauki.pl/articles/1955517.pdf
Data publikacji:
1997-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.90.+n
74.10.+v
74.70.-b
Opis:
The influence of the mechanical milling and subsequent thermal relaxation on magnetic and superconducting behaviour of YBa$\text{}_{2}$(Cu$\text{}_{1-x}$Fe $\text{}_{x}$)$\text{}_{3}$O$\text{}_{y}$ system has been studied. Two methods of heat treatment were used: Set I - slow cooling from 980°C in flowing O$\text{}_{2}$ and Set II - reducing at 770°C in flowing Ar$\text{}_{2}$ followed by reoxidation in flowing O$\text{}_{2}$ below 400°C. The transition to superconductivity, diamagnetic response, critical current density and the effective magnetic moment in the normal state have been estimated. Our measurements indicate that the reducing atmosphere preparation is less detrimental on superconducting properties. The results are discussed in terms of occupancy Cu sites by Fe and redistribution of oxygen atoms.
Źródło:
Acta Physica Polonica A; 1997, 91, 2; 355-358
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of $NdFe_{0.9}Mn_{0.1}O_{3}$
Autorzy:
Zentková, M.
Lazúrová, J.
Kováč, J.
Mihalik, M.
Briančin, J.
Fitta, M.
Kusigerski, V.
Powiązania:
https://bibliotekanauki.pl/articles/1371226.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.-y
75.47.Lx
75.30.-m
75.30.Kz
75.30.Et
75.30.Cr
Opis:
In our paper we study effect of Mn for Fe substitution on magnetic properties of $NdFe_{x-1}Mn_{x}O_{3}$ compounds for x=0 and 0.1, which have been grown by the OFZ technique. The Néel temperature decreases from $T_{N1}$=691 K to $T_{N1}$=621 K, and the anomaly in AC susceptibility, related to spin reorientation, vanishes with Mn substitution. Low temperature heat capacity measurement for sample with x=0.1 revealed that substitution of Mn for Fe shifts a Schottky-type anomaly at $T_{sh}$ to higher temperatures. Another anomaly is generated by doping at $T_{max}$=11 K. The anomaly is smeared out by magnetic field, confirming its magnetic origin.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 306-307
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Temperature on Magnetization Processes in Amorphous Rapidly Solidified FeSiB/CoSiB Bilayer Ribbons
Autorzy:
Capik, M.
Švec, P.
Marcin, J.
Kováč, J.
Sopko, M.
Janičkovič, D.
Škorvánek, I.
Powiązania:
https://bibliotekanauki.pl/articles/1200803.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Kj
75.60.Ej
75.80.+q
Opis:
Amorphous bilayers consisting of Fe-Si-B and Co-Si-B layers have been prepared by planar flow casting from a single crucible using a double-nozzle technique. Temperature dependencies of magnetization and hysteresis loops have been investigated in a wide temperature range. At room temperature, the effects of interlayer stresses, induced in material due to different thermal expansion coefficients of two mechanically interconnected soft magnetic layers, resulted in rounded hysteresis loops with flattened central part, indicating a dominant role of magnetization rotational processes. With an increase of measurement temperature, the interlayer stresses are relieved and the hysteresis loops became more squared.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 120-121
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Viscosity Dependence of a Magnetic Fluid Nanoparticles Concentration
Autorzy:
Tóthová, J.
Kováč, J.
Kopčanský, P.
Rajňák, M.
Paulovičová, K.
Timko, M.
Józefczak, A.
Powiązania:
https://bibliotekanauki.pl/articles/1201929.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
07.55.Jg
75.50.Mm
83.85.Jn
Opis:
In this work we have studied the effect of temperature on the viscosity of magnetic fluids (MFs) based on the transformer oil ITO 100. The volume concentration of suspended magnetic particles (MPs) changed from 0.25 to 1%. Rheological characterization of MFs was performed using a vibroviscometer at working frequency of 30 Hz. The temperature dependence of the viscosity was measured in the temperature range from 20 up to 50 °C. The magnetization of different concentrations of MPs in MFs was determined by using the vibrating sample magnetometer.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 278-279
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties and Sorption Activity of Mechanically Activated Magnetite $Fe_3O_4$
Autorzy:
Baláž, P.
Timko, M.
Kováč, J.
Bujňáková, Z.
Ďurišin, J.
Myndyk, M.
Šepelák, V.
Powiązania:
https://bibliotekanauki.pl/articles/1535173.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.60.Ej
61.05.cp
76.80.+y
Opis:
It is known that the action of mechanical forces on solids (mechanical activation and/or mechanochemistry) leads to changes of their properties and reactivity. We have studied the physico-chemical and sorption properties of magnetite $Fe_3O_4$ (Kiruna, Sweden) mechanically activated in a planetary mill. Several methods such as X-ray diffractometry, Mössbauer spectroscopy, magnetometry, specific surface area measurement as well as arsenic sorption tests have been applied. By X-ray diffractometry strong amorphisation of magnetite has been evidenced. In parallel, specific surface area increased from 0.1 $m^2//g$ for the reference (non-milled) sample to the values 0.5-6.1 $m^2//g$ for milled samples. The Mössbauer spectrum of the reference sample is well fitted with two subspectra corresponding to tetrahedrally (A) and octahedrally (B) coordinated iron cations in the spinel structure of $Fe_3O_4$. In mechanically activated samples (B)-site subspectrum becomes asymmetric, while (A)-site spectrum remains more or less unchanged. The more covalent character of the Fe(A)-O bond compared to the Fe(B)-O bond can explain qualitatively why the spin-density transfer from (A) to (B) in the spinel structure is more effective than vice versa. The value of the saturation magnetization at room temperature was 67.4 ≈ 43.6 emu/g which is significantly lower than that of the bulk particles 92 emu/g. This reduction may be attributed to the surface disorder or spin canting at the particle surface. During the milling process the coercivity value increases from 150 Oe up to 460 Oe with milling time. This increase can be related to the fact that magnetic anisotropy may increase when particle size decreases. The sorption activity of $Fe_3O_4$ was enhanced as a consequence of its disordering: 88% of $As^{3+}$ was captured for the mechanically activated sample in comparison with 0% for the non-milled one.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 1005-1007
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of AlN Buffer Layer Deposition Temperature οn Properties of GaN HVPE Layers
Autorzy:
Prażmowska, J.
Korbutowicz, R.
Wośko, M.
Paszkiewicz, R.
Kovač, J.
Srnanek, R.
Tłaczała, M.
Powiązania:
https://bibliotekanauki.pl/articles/1807541.pdf
Data publikacji:
2009-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.10.Bk
81.15.Gh
81.15.Kk
Opis:
Gallium nitride layers were deposited on AlN and double layer (AlN/AlGaN) buffers grown at various temperatures on $Al_{2}O_{3}$. Stress in layers was evaluated based on the Raman scattering and photoluminescence measurements. The obtained values were less than 1 GPa.
Źródło:
Acta Physica Polonica A; 2009, 116, S; S-123-S-125
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of Fiber Laser Pulse Processing on Coercivity and Nanohardness of Fe-3.2Si Grain-Oriented Electrical Steel in relation with its Surface Changes and Magnetic Domains Modifications
Autorzy:
Puchý, V.
Falat, L.
Kováč, F.
Petryshynets, I.
Džunda, R.
Šebek, M.
Powiązania:
https://bibliotekanauki.pl/articles/1032305.pdf
Data publikacji:
2017-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.80.Ba
81.05.Bx
81.40.Rs
81.40.-z
75.60.Ch
79.20.Eb
Opis:
Fiber laser scribing of Fe-3.2Si grain-oriented electrical steel was carried out using three different laser pulse regimes, namely a single pulse laser regime, multipulse laser regime and multipulse laser regime with modulation of laser pulses. The samples were tested for coercivity and nanohardness before and after laser processing. Clear improvements in soft magnetic characteristics were observed for all the regimes using the lowest single pulse energy of 0.6 mJ. The best improvement i.e. the most significant decrease in coercivity was obtained after the regime with 5 pulses. Further increasing in both pulse energy and pulse number resulted only in detrimental effects on both magnetic and mechanical characteristics. Introduction of 50 kHz pulse modulation within 100-pulse laser regimes resulted in lower coercivity values in comparison with the same regimes without modulation. The major effects responsible for the observed improvement are related to optimal refinement and rearrangement of magnetic domains determined by the balance of laser-induced residual stresses and plastic deformation at the surface of the treated material. Thus the fiber laser pulse processing has been recognised as a useful and energy efficient tool in obtaining electrical steels for power transformers with lower core losses.
Źródło:
Acta Physica Polonica A; 2017, 131, 6; 1445-1449
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of Sm addition on the microstructure and superconducting properties of YBCO bulk superconductors
Autorzy:
Volochová, D.
Diko, P.
Piovarči, S.
Antal, V.
Kováč, J.
Jirsa, M.
Powiązania:
https://bibliotekanauki.pl/articles/1054772.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.62.Dh
81.10.Fq
61.72.-y
74.25.Ha
74.25.Sv
Opis:
The effect of Sm addition on the microstructure and superconducting properties of Y-Ba-Cu-O (YBCO) bulk superconductors has been studied. Nominal composition: 1 mol YBa₂Cu₃O_{7-δ} + 0.25 mol Y₂O₃ + 1 wt% CeO₂ was enriched with different amounts of SmBa₂Cu₃O_y powder with the aim to increase critical current density, J_c, especially in higher magnetic fields by introducing additional pinning centers. Single grain YBCO bulk superconductors with SmBa₂Cu₃O_y (Y123-Sm) addition were prepared by the optimized top seeded melt growth process. Microstructure analysis, performed by polarized light microscope, revealed that SmBa₂Cu₃O_y addition leads to a higher amount of slightly coarser Y₂BaCuO₅ particles, which is related to lower critical current densities (J_c ≈ 6×10⁴ A/cm²) of the YBCO samples with SmBa₂Cu₃O_y addition in low magnetic fields. On the other hand, an enhancement of critical current density, J_c, in higher magnetic fields was observed for Y123-Sm samples. Moreover, a maximum trapped magnetic field, B_{tmax}, of 564 mT at 77 K in Y123-Sm, x=0.0025 sample (Ø 17.2 mm) was 43% higher than that for YBCO sample without any addition.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 1009-1011
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Critical Current Density and Microstructure of $NdBa_2Cu_3O_7$ Single Crystal
Autorzy:
Diko, P.
Zmorayová, K.
Šefčiková, M.
Antal, V.
Kováč, J.
Yao, X.
Powiązania:
https://bibliotekanauki.pl/articles/1535339.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Ha
74.25.Sv
74.62.Bf
Opis:
The top-seeded solution growth method was used to grow NdBCOss single crystals in air. The microstructure of the samples has shown that the oxygenation crack structure developed in the single crystals. The intrinsic critical current density was estimated to be at least twice higher than the value of volume critical current density determined from the magnetization measurements.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 1028-1030
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effects of Laser Surface Hardening on Microstructural Characteristics and Wear Resistance of AISI H11 Hot Work Tool Steel
Autorzy:
Šebek, M.
Falat, L.
Kováč, F.
Petryshynets, I.
Horňak, P.
Girman, V.
Powiązania:
https://bibliotekanauki.pl/articles/352543.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hot work tool steel
laser hardening
microstructure
hardness
wear resistance
Opis:
The present study deals with the effects of laser surface treatment on microstructure evolution and wear resistance of AISI H11 hot work tool steel in quenched and tempered condition. The most upper laser-affected zone is characterized by re-melted microstructure consisting of dendrite cells with fresh non-tempered martensite, retained austenite and inter-dendritic carbidic network. The subsolidus microstructure just beneath the re-melted zone represents the most laser surface hardened zone consisting of fresh non-tempered martensite with fine and coarse carbides as a result of overheating the original QT substrate microstructure. The highest microhardness values in the range from 775 to 857 HV were measured for the LSH microstructure and the most softened microstructure exhibited the minimum hardness of 530 HV. The laser treated samples showed the improvement of their surface wear resistance by 35%.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 3; 1721-1726
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanochemically Synthesized CuFeSe₂ Nanoparticles and Their Properties
Autorzy:
Dutková, E.
Škorvánek, I.
Sayagués, M.
Zorkovská, A.
Kováč, J.
Baláž, P.
Powiązania:
https://bibliotekanauki.pl/articles/1032137.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Hd
81.07.Wx
81.20.Wk
Opis:
The mechanochemical synthesis of nanocrystalline CuFeSe₂ particles prepared by high-energy milling in a planetary mill in an argon atmosphere from copper, iron, and selenium for 60 min is reported for the first time. The CuFeSe₂ nanoparticles crystallize in tetragonal structure with mean crystallite size of about 32±1 nm. High resolution transmission electron microscopy measurements confirmed the presence of agglomerates which are formed by small nanocrystalline domains (5-40 nm). The magnetic data revealed that paramagnetic CuFeSe₂ nanoparticles coexist with a small amount of ferromagnetic impurities at room temperature. The magnetic transition towards a weak ferromagnetic or ferrimagnetic behavior occurs in CuFeSe₂ at approximately 79 K. The band gap of the CuFeSe₂ particles is 0.95 eV which is wider than the band gap in bulk materials (0.16 eV), which could be in many aspects of application more beneficial.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 1156-1158
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Carbon Nanotubes
Autorzy:
Jeníková, M.
Zakuťanská, K.
Kováč, J.
Girman, V.
Kopčanský, P.
Tomašovičová, N.
Powiązania:
https://bibliotekanauki.pl/articles/1032760.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.48.De
74.25.nd
68.37.Lp
75.75.-c
Opis:
The aim of the presented work was to characterize single-walled carbon nanotubes as well as multi-walled carbon nanotubes by transmission electron microscopy, the Raman spectroscopy and magnetization measurements to obtain information about their size, structure, and magnetic properties. We show that having different carbon nanotubes one can easily distinguish the single-wall or multi-wall carbon nanotubes and determine their quality. The obtained results show that carbon nanotubes can be diamagnetic or ferromagnetic depending on their structural parameters.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 952-954
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of model lightening system and design of PID controllers for the purpose of energy savings by using of MATLAB and their functionality in LabVIEW
Identyfikacja modelu systemu rozjaśniania i zaprojektowania regulatora PID w celu oszczędności energii przy wykorzystaniu programu MATLAB i funkcjonalności LabVIEW
Autorzy:
Nagy, L
Palková, Z
Valíček, J
Kiedrowicz, M
Rokosz, K
Kovač, P
Powiązania:
https://bibliotekanauki.pl/articles/1819293.pdf
Data publikacji:
2012
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
sterowanie wzrostu roślin
regulator PID
rośliny szklarniowe
sterowanie oświetleniem
Opis:
System sterowany jest częścią pętli i konieczne jest rozważenie go jako osobnej części z konkretnej nieruchomości. Podczas wyboru właściwego regulatora PID ważne jest, aby zrozumieć dynamiczne właściwości kontrolowanego systemu. Na opis tego obiektu zostały opracowane różne metody bilansów energii i następnych modeli matematycznych korygujących przejęcie funkcji transferowych. W praktyce lepiej jest użyć metod, których obserwujemy zachowanie dla konkretnych warunków systemowych (na przykład odpowiedzi na jednostkowy skok na wejściu lub częstotliwość sygnału). Według Behaving wiemy jak matematycznie opisać systemu i następnie wybrać właściwy rodzaj regulatora PID z jego parametrami. Ten artykuł skupia się na identyfikacji systemu oświetlenia dla uprawy roślin szklarniowych oraz prawidłowego zaprojektowania parametrów regulatora PID do sterowania oświetleniem, tak aby zorientowany był on na oszczędności energii.
Źródło:
Rocznik Ochrona Środowiska; 2012, Tom 14; 247-261
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of Bacterial Nanoparticles
Autorzy:
Timko, M.
Džarová, A.
Kováč, J.
Kopčanský, P.
Gojzewski, H.
Szlaferek, A.
Powiązania:
https://bibliotekanauki.pl/articles/1810601.pdf
Data publikacji:
2009-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
47.65.Cb
51.60.+a
75.30.Gw
75.50.Tt
75.60.Nt
75.60.Ej
75.75.+a
Opis:
The objective of this study is to prepare and study magnetic properties of biological magnetic nanoparticles (magnetosomes) as a product of biomineralization process of magnetotactic bacteria Magnetospirillum sp. AMB-1. From temperature dependence of remanent magnetization and coercive field the Verwey transition is clearly seen at 105 K as a consequence of the large anisotropy along the chains of magnetosomes.
Źródło:
Acta Physica Polonica A; 2009, 115, 1; 381-383
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Magnetosomes After Exposure to the Effect of the Sonication and Ultracentrifugation
Autorzy:
Molčan, M.
Hashim, A.
Kováč, J.
Rajňák, M.
Kopčanský, P.
Makowski, M.
Gojzewski, H.
Molokáč, M.
Hvizdák, L.
Timko, M.
Powiązania:
https://bibliotekanauki.pl/articles/1368025.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.07.-b
75.60.-d
87.50.Y-
68.37.-d
Opis:
Magnetosomes are intracellular organelles of widespread aquatic microorganisms called Magnetotactic bacteria. At present they are under investigation especially in biomedical applications. This ability depends on the presence of intracellular magnetosomes which are composed of two parts: first, nanometer-sized magnetite $(Fe_{3}O_{4})$ or greigite $(Fe_{3}S_{4})$ crystals (magnetosome crystal), depending on the bacterial species; and second, the bilayer membrane surrounding the crystal (magnetosome membrane). The magnetosomes were prepared by biomineralization process of magnetotactic bacteria Magnetospirillum Magnetotacticum sp. AMB-1. The isolated magnetosome chains (sample M) were centrifugated at speed of 100000 rpm for 4 hours (sample UM) and sonicated at power of 120 W for 3 hours (sample SM), respectively. The prepared suspensions were investigated with respect to morphological, structural and magnetic properties. The results from scanning electron microscopy showed that isolated chains of magnetosomes were partially broken to smaller ones after ultracentrifugation. On the other hand the application of the sonication process caused the formation of individual magnetosomes (unordered in chain). These results were confirmed by coercivity and magnetization saturation measurements.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 198-199
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elimination of Magnetic Nanoparticles with Various Surface Modifications from the Bloodstream in vivo
Autorzy:
Tomasovicova, N.
Khmara, I.
Koneracka, M.
Zavisova, V.
Kubovcikova, M.
Antal, I.
Kovac, J.
Muckova, M.
Kopcansky, P.
Powiązania:
https://bibliotekanauki.pl/articles/1032816.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Gg
75.50.Tt
87.85.jj
Opis:
The magnetic nanoparticles with the core diameter 10 nm stabilized by sodium oleate and bovine serum albumin in phosphate buffer have been modified by different biocompatible substances such as poly(ethylene glycol) (PEG), dextran (DEX), and polyvinylpyrrolidone (PVP). Prepared biocompatible magnetic fluids were characterized to obtain the particle size distribution using scanning electron microscopy and the dynamic light scattering method. To study the elimination of different modified magnetic nanoparticles from bloodstream, the biocompatible samples were applied intravenously to the mice bloodstream with further blood specimens collecting in given time intervals. Magnetic moment of the lyophilized blood samples was measured by SQUID magnetometer. Time dependence of magnetic moment of magnetic nanoparticles and magnetic nanoparticles modified by DEX, PEG and PVP normalized to the Fe₃O₄ showed that the circulation time of magnetic nanoparticles in the bloodstream depends on the substance used for modification. The unmodified magnetic nanoparticles were trapped by reticuloendothelial system within 1 h while magnetic nanoparticles modified by DEX, PEG and PVP circulated in blood up to 3 h.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 1159-1161
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanochemical Reduction of Chalcopyrite CuFeS₂: Changes in Composition and Magnetic Properties
Autorzy:
Baláž, P.
Zorkovská, A.
Baláž, M.
Kováč, J.
Tešinský, M.
Osserov, T.
Guseynova, G.
Ketegenov, T.
Powiązania:
https://bibliotekanauki.pl/articles/1032642.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Pp
81.05.Hd
Opis:
High-energy milling of sulphides with a reactive metal in so-called mechanochemical reduction mode can lead to products in nanorange and to composition which simplifies the following metallurgical processing. Chalcopyrite CuFeS₂, a ternary semiconductor with antiferromagnetic properties represents promising candidate as an advanced material for use in inexpensive nanoelectronics (solar cells, magnetic area), as well as copper ore source in metallurgical operations. In this work, the process of mechanochemical reduction of chalcopyrite with elemental iron is studied. The composition and properties of nanopowder prepared by high-energy milling were analyzed by X-ray diffraction and magnetic measurements. Most of the reaction takes place during 30 min with chalcocite Cu₂S and troilite FeS as the only reaction products. The magnetic investigations reveal significant increase of saturation magnetization as a result of milling. Unlike the conventional high-temperature reduction of chalcopyrite, the mechanochemical reduction is fast and ambient temperature and atmospheric pressure are sufficient for its propagation.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 1165-1167
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Sm and Yb Pollution on Superconducting Properties of YBCO Bulk Superconductors
Autorzy:
Volochová, D.
Jurek, K.
Radušovská, M.
Piovarči, S.
Antal, V.
Kováč, J.
Jirsa, M.
Diko, P.
Powiązania:
https://bibliotekanauki.pl/articles/1371573.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.60.Bf
74.72.-h
81.40.Rs
74.25.Ha
74.81.Bd
74.25.Op
Opis:
$YBa_{2}Cu_{3}O_{7-δ }$ (YBCO, Y-123) bulk superconductors with a nominal composition $Y_{1.5}Ba_{2}Cu_{3}O_{x}$ and 1 wt% $CeO_{2}$ addition were prepared by the Top Seeded Melt Growth (TSMG) process. Small single-crystalline pieces, cut from the $SmBa_{2}Cu_{3}O_{y}$ (Sm-123) bulk, were used for seeding of epitaxial growth. Wavelength-dispersive spectrometry (WDS) confirmed the presence of 0.1 wt% Sm from the seed and 0.25 wt% Yb from the substrate, practically in the whole sample volume. The influence of this Sm and Yb contamination on superconducting properties of grown bulk materials is reported.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 358-359
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of Morphology on Magnetic Properties of Magnetosomes
Autorzy:
Hashim, A.
Molčan, M.
Kovač, J.
Varchulová, Z.
Gojzewski, H.
Makowski, M.
Kopčansky, P.
Tomori, Z.
Timko, M.
Powiązania:
https://bibliotekanauki.pl/articles/1428653.pdf
Data publikacji:
2012-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
47.65.Cb
51.60.+a
75.30.Gw
75.50.Tt
75.60.Nt
75.60.Ej
Opis:
Cultivation process was changed three times. The culture medium was enriched by more amount ferric quinate (FQ magnetosomes sample) and more amounts Wolfe's vitamin solution (WVS magnetosomes sample) comparing to normal culture medium (NP magnetosomes sample). NP sample of magnetosomes shows zero coercivity and behaves superparamagnetically. The increase of coercivity (6.5 Oe for WVS and 20 Oe for FQ) may be caused by higher value of shape anisotropy and reveals stronger magnetic correlations between particles of magnetite chains.
Źródło:
Acta Physica Polonica A; 2012, 121, 5-6; 1250-1252
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microstructure and Magnetic Properties of La-Ca-Sr-Mn-O Perovskite Ceramics
Autorzy:
Zmorayova, K.
Antal, V.
Radusovska, M.
Piovarci, S.
Kováč, J.
Kavecansky, V.
Diko, P.
Powiązania:
https://bibliotekanauki.pl/articles/1367705.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Sg
75.47.Lx
77.80.Bh
81.20.Ev
81.30.Fb
Opis:
$La_{0.67}Ca_{0.33-x}Sr_{x}MnO_{3}$ (x=0.33; 0.03; 0) (LCSM) perovskite magnetocaloric ceramics were prepared by solid state synthesis in air and sintering at 1520°. The phase composition was checked by x-ray powder diffraction. Microstructure analyses were done by scanning electron microscopy. The influence of high pressure oxygenation on magnetisation behaviour is shown.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 168-169
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of RF ICP PECVD process parameters of diamond-like carbon films on DC bias and optical emission spectra
Autorzy:
Oleszkiewicz, W
Markowski, J
Srnanek, R
Kijaszek, W
Gryglewicz, J
Kovac, J
Tlaczala, M
Powiązania:
https://bibliotekanauki.pl/articles/173686.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
PECVD
diamond-like carbon layers
OES
Raman spectroscopy
AFM
Opis:
The work presents the results of a research carried out with PlasmaLab Plus 100 system, manufactured by Oxford Instruments Company. The system was configured for deposition of diamond-like carbon films by ICP PECVD method. The change of an initial value of DC bias was investigated as a function of set values of the generator power (RF generator and ICP generator) in the constant power of the RF generator operation mode. The research shows that the value of DC bias nearly linearly depends on the RF generator power value and is affected only in a small degree by the power of ICP discharge. The capability of an installed OES spectrometer has been used to ensure the same starting conditions for the deposition processes of DLC films. The analysis of OES spectra of RF plasma discharge used in the deposition processes shows that the increase in ICP discharge power value results in the increased efficiency of the ionization process of a gaseous precursor (CH4). The quality of deposited DLC layers was examined by Raman spectroscopy. Basing on the acquired Raman spectra, the theoretical content of sp3 bonds in the structure of the film was estimated. The content is ranging from 30% to 65% and depends on ICP PECVD deposition process parameters.
Źródło:
Optica Applicata; 2013, 43, 1; 109-115
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł

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