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1

Influence of Sr2+ Dopant on Microstructure and Electric Properties of (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 (BCZT) Ceramics

Radoszewska D., Goryczka T., Adamczyk M., Wodecka-Duś B., Bochenek D., Kozielski L.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 3

1295--1302

EN

The discovery of (BaxCa1-x)(ZryTi 1-x)O3 lead-free ceramics drawn a lot of attention to those novel materials because of their excellent piezoelectric properties. However, quite a little attention has been paid to other features of the material. This article reports a wide range of research, including composition, structure and microstructure, dielectric response and impedance spectroscopy in order to systematize and expand knowledge about this peculiar ceramics and strontium doping effect on its properties. In order to test that influence a series of samples with various strontium concentration, precisely the admixtures of 0.02, 0.04 and 0.06 mol% were prepared, as well as basic ceramics to compare obtained results.

2

Electrical and Thermal Properties of Na1-xLixNbO3 (x = 0.08, 0.1 and 0.2) Ceramics Near the Morphotropic Phase Boundary Region

Konieczny K., Czaja P.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2A

539--544

EN

Na1-xLixNbO3 ceramics (for x = 0.08, 0.1, 0.2) were fabricated by the conventional solid state reaction method. The influence of LiNbO3 on the microstructure, electric, thermal properties of Na1-xLixNbO3 ceramics was studied and a significant influence of doped Li ions on the electrical properties was observed. The electrical properties were improved and are described as the best for x = 0.1 (near a morphotropic phase boundary) Na1-xLixNbO3 solid solutions. After crossing the morphotropic phase boundary for x = 0.2, the electric properties are getting worse. These types of solid compounds show some interesting properties suitable for practical applications.

3

Nanocrystalline Ag-Re Composite as a Potential Material for Electric Contacts Fabrication

Kołacz D., Księżarek S., Woch M., Karwan-Baczewska J., Staszewski M., Rudnicki K., Borkowski P., Sienicki A.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 4

1847--1852

EN

A new silver-based composite material with an addition of 1 and 10 mass % of rhenium, for prospective application in the production of electric contacts, has been presented. The paper shows results of the research and experimental works aimed at developing technology for fabrication of semiproducts (wires and bimetallic contacts) by classical powder metallurgy methods and by a method enabling production of nanocrystalline composite. At each stage of the processes involved, physical, mechanical and technological properties of the materials were investigated. Particular attention was given to final products and semiproducts prepared in a form of bimetallic contacts. It was found that the composite with nanocrystalline structure may be a good material for ecological electric contacts.

4

Porównanie wybranych właściwości diod elektroluminescencyjnych

Wrona I. A., Jarosik M. W.

Journal of Technology and Exploitation in Mechanical Engineering

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2015

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Vol. 1, nr 1-2

107--123

PL

W ramach pracy przeanalizowano wybrane właściwości niebieskich diod elektrolumi-nescencyjnych w celu doboru odpowiednich parametrów umożliwiających wykorzystanie badanych diod do kalibracji detektora promieniowania Czerenkowa. W szczególności eksperymentalnie przebadano 10 modeli diod LED mierząc czas narastania, szerokość impulsu, impedancję zastępczą oraz moc optyczną. Pomiary elektrycznych właściwości diod zostały wykonane przy użyciu analizatora impedancji oraz kąta przesunięcia fazowego. Na podstawie uzyskanych rezultatów możliwe było wyznaczenie rezystancji oraz pojemności diod przy różnych wartościach napięcia. Charakterystyki czasowe wyznaczono przy użyciu oscyloskopu LeCroyWaverunner 62Xi, generatora funkcyjnego DDS oraz fotopowielacza. Pomiary wykonano dla różnych wartości napięcia oraz przy wykorzystaniu kilku filtrów ograniczających natężenie światła docierającego do fotopowielacza. W każdym rozpatrywanym przypadku badane były 2 różne diody tego samego typu, co pozwoliło na określenie różnic między poszczególnymi egzemplarzami. W ramach badań właściwości optycznych wyznaczono moc optyczną diod. Następnie wykorzystując uzyskane rezultaty obliczono liczbę fotonów przypadających na pojedynczy impuls. Do pomiarów wykorzystano miernik Newport 1835-C wyposażony w detektor 818-UV/CM. Wykonane badania miały na celu wyselekcjonowanie diod LED o odpowiednich parametrach czasowych, elektrycznych i optycznych, które najlepiej sprawdzą się podczas kalibracji detektora promieniowania Czerenkowa. W kolejnym kroku planowane są badania polegające m.in. na testowaniu właściwości układów diod w różnych połączeniach.

EN

In the paper some selected properties of the blue light-emitting diodes planned to be used to calibration of Cherenkov radiation’s detector have been analysed. In particular ten LEDs models have been experimentally examined by measuring the rise time, pulse width, complex impedance and optical power. Measurements of LEDs electric properties have been made by using impedance and phase analyser. On the basis of obtained results the resistance and capacitance of each LED for different voltage values have been calculated. Timing characteristics were determined by using LeCroyWaverunner 62Xi oscilloscope, DDS function generator and photomultiplier. Measurements have been performed for different values of voltage and a few neutral density filters to restrict the intensity of light reaching the photomultiplier have been used. In each case two different diodes of the same type have been tested to define differences between copies. Research of optical properties consisted of measuring optical power of LEDs. Then, using the obtained results, number of photons per pulse has been calculated. To measurement a Newport 1835-C optical power measurer fitted with a 818-UV/CM detector has been used. Research has been performed to select the diode with relevant parameters, which best suits during calibration of Cherenkov radiation’s detector. In the next step testing properties of LEDs in various connections is planned.

5

The Influence of Pet Fibres Surface Enzymatic Modification on the Selected Properties

Kardas I., Lipp-Symonowicz B., Sztajnowski S., Wojciechowska D.

Autex Research Journal

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2014

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Vol. 14, no. 3

179--186

EN

The effect of changes in the surface structure of glossy polyester filaments from poly(ethylene terephthalate) in terms of its micro-topography, molecular and supermolecular structure of the fibre surface layers on selected fibre surface and volumetric properties has been assessed. The performed tests and measurements have shown that the change in the general surface characteristics of PET fibres (micro-topography and hydrophilicity) results in very beneficial changes in both their volumetric (dyeability) and surface properties (wettability, pilling, oil-soil removal and electric properties).

6

Zastosowanie sieci Kohonena i wykresu rozrzutu do identyfikacji grup miodów według ich cech elektrycznych

Łuczycka D., Pruski K.

Inżynieria Rolnicza

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2012

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R. 16, nr 2, t. 2

169-175

PL

Celem pracy jest wykonanie analiz symulacyjnych bazujących na sieci Kohonena i skalowaniu wielowymiarowym, oraz możliwość zastosowania tych technik do identyfikacji grup miodów odmianowych pod względem cech elektrycznych. Przebadano przenikalność elektryczną, współczynnik strat dielektrycznych oraz przewodność szesnastu gatunków miodów (spadziowe i nektarowe). W wyniku przeprowadzonych analiz stwierdzono, że sieci Kohonena oraz skalowanie wielowymiarowe są dobrymi narzędziami do określania liczności i składu gatunkowego grup miodów odmianowych. Właściwą architekturą sieci Kohonena tworzącą poprawną mapę topologiczną, dla analizowanych cech miodu, jest mapa zbudowana z 9 neuronów wyjściowych o wymiarach 3x3.

EN

The purpose of the work is to carry out simulation analysis which are based on Kohonen map and multidimensional scaling and the possibility of application of these technologies for identification of cultivar honey groups in relation to their electric properties. Electric conductivity, coefficient of dielectric losses and conductivity of 16 cultivars of honey (honeydew and nectar honey) were researched. As a result of the analysis which was carried out, it was determined that Kohonen map and multidimensional scaling are good devices for determining the number and species composition of cultivar honey groups. A map formed of 9 output neurons of 3x3 dimensions is the proper architecture of Kohonen map which forms a correct topology map for the analysed properties of honey.

7

Wpływ temperatury na cechy dielektryczne miodu

Łuczycka D., Szewczyk A., Pruski K.

Inżynieria Rolnicza

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2011

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R. 15, nr 9

117-122

PL

Celem pracy było określenie wpływu temperatury miodu na wartości charakteryzujących go cech elektrycznych. Przebadano 5 gatunków miodów w tym jeden miód sztuczny. W wyniku przeprowadzonych analiz okazało się że, istnieje silna zależności miedzy współczynnikiem strat dielektrycznych a gatunkami badanych miodów. Właściwym zakresem częstotliwości do różnicowania miodów jest zakres od 1-3KHz.

EN

The purpose of the study was to determine influence of temperature of honey on electric properties, which characterise it. Five kinds of honey including artificial honey were tested. The conducted analysis proved that there is a strong interdependence between coefficients of dielectric loses and tested kinds of honey. The range of 1-3 kHz is the most appropriate for differentiating kinds of honey.

8

Elektryczne metody wykrywania zafałszowań miodu

Łuczycka D., Szewczyk A., Pruski K.

Inżynieria Rolnicza

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2011

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R. 15, nr 5

165-170

PL

Celem pracy była analiza możliwości zastosowania oznaczeń cech elektrycznych do określania jakości miodu, a w szczególności do oceny zafałszowań miodu za pomocą zastępowania miodu surogatem lub miodem ekspresowym pozyskiwanym w efekcie karmienia pszczół inwertem. W efekcie przeprowadzonych pomiarów oraz analizy uzyskanych wyników stwierdzono, że przenikalność elektryczna może służyć do szybkiego wykrywania zafałszowań miodów jak również ich rozróżniania (nektarowe/spadziowe) - wśród badanych próbek wyróżniono trzy grupy homogeniczne. Właściwym zakresem częstotliwości pola elektromagnetycznego do prowadzenia tego typu oznaczeń jest zakres 1-3 kHz.

EN

The purpose of the survey was to analyse the possibilities of application of electric feature denotations for determination of honey quality, particularly for the evaluation of honey falsifications by way of honey substitution with a surrogate or express honey obtained as a result of feeding bees with inverted sugar syrup. As a result of the conducted measurements as well as the analysis of the obtained results, it was stated that permittivity may be used for quick detection of honey falsifications and their distinction (flower nectar honey/honeydew honey) - three homogeneous groups were distinguished among the tested samples. The scope of 1-3 kHz is the proper scope of electromagnetic field frequency.

9

Niskotemperaturowe elektroizolacyjne kompozyty epoksydowe

Bursa J., Pomianowski J.

Przegląd Elektrotechniczny

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2010

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R. 86, nr 11b

186-188

PL

Przedstawiono wyniki badań kilku kompozytów epoksydowych utwardzanych w temperaturze pokojowej. Zbadano wpływ głównych składników (żywica, napełniacze) na właściwości elektryczne epoksydowych materiałów elektroizolacyjnych.

EN

The paper presents results of research on several epoxy composites hardener in the room temperature. The influence of main components (resin, fillers) on electric properties of epoxy electroinsulating materials has been tested.

10

Investigation of the screen printed contacts of silicon solar cells using Transmission Line Model

Dobrzański L. A., Musztyfaga M., Drygała A., Panek P.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 41, nr 1-2

57-65

EN

Purpose: The aim of the paper is to analyze how to improve the quality of the screen printed contacts of silicon solar cells. This means forming front side grid in order to decrease contact resistance. Design/methodology/approach: The topography of screen printed contacts were investigated using ZEISS SUPRA 25 scanning electron microscope (SEM) with an energy dispersive X-ray (EDS) spectrometer for microchemical analysis. Front collection grid was created using two types of Ag pastes.The Transmission Line Model (TLM) patterns were fabricated by screen printing method on p – type Czochralski silicon Cz-Si wafer with n+ emitter without texture and with a titanium oxide (TiOx) layer as an antireflection coating (ARC). Electrical properties of contacts were investigated using TLM. Findings: This work presents a conventional analysis of a screen printing process for contact formation in the crystalline silicon solar cells. The seed layer was created using silver pasts by the screen printed metallization. These contact structures were investigated using SEM to gain a better understanding of the obtained electrical parameters. Research limitations/implications: The contact resistance of the screen-printed metallization depends not only on the kind of applied paste and firing conditions, but is also strongly influenced by the surface morphology of the silicon substrate. Practical implications: Contact formation is an important production step to be optimized in the development of high efficiency solar cells. Originality/value: The effect of co-firing different pasts (especially a past, which was prepared using silver nano-powder) on electrical properties of silicon wafers.

11

Mastitis detection based on electric conductivity of milk

Janzekovic M., Brus M., Mursec B., Vinis P., Stajnko D., Cus F.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 34, nr 1

39-46

EN

Purpose: If measurements of the increased total count of somatic cells in the individual udder quarter or in the whole udder could be determined with electric conductivity by means of the microprocessor-controlled device Mastitron LF 3000 enough precisely to predict the presence of subclinical mastitis. Design/methodology/approach: The occurrence of increased count of somatic cells in milk was found out group by group by the method of measuring the electric conductivity of milk. For the milk conductivity the average measurement from all four udder quarters was taken into account. The population of 102 lactating cows (Black and white, Simmental and Brown Swiss breed) on seven farms fore three summer months was observed. Findings: It was established that higher average electric conductivity than 6.5 mS/cm confirmed in 80% also the increased count of somatic cells in milk. When evaluating the differences between the quarters exceeding 1 mS/cm also a higher total count of somatic cells was confirmed in 73.7%. Moreover, statistically significant relation (P<0.01) between the CMT test and the ECM was found out so it can be claimed that the two methods do not exclude themselves mutually. Research limitations/implications: It was found that the reliability of the ECM in our case was 80% depending to a large extent on the milk composition which changed depending on the stage of lactation, type of feed and general health condition of animals. For a more reliable, accurate and faster implementation of the ECM method further researches will be necessary. Practical implications: Though the ECM method of determination of the subclinical mastitis of the milch-cows is well established in the world, it is not yet known well enough in the Slovene practice as a method of diagnosing the subclinical mastitis. Originality/value: It was found that the results of our research in production circumstances were comparable with the indications of the maker and foreign researchers.

12

Achieving combined high strength and high conductivity in re-processed Cu-Cr alloy

Olofinjanaa A. O., Tan K. S.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 35, nr 1

14-20

EN

achieve the optimum combination for strength and conductivity in copper based alloys. However, precipitation strengthened Cu- alloys are limited to very dilute concentration thereby limiting the volume proportion hardening precipitates. In this work, we report the investigation of the reprocessing of higher Cr concentration Cu- based alloys via rapid solidification. Design/methodology/approach: The ingot alloys with Cr content up to 10 wt.% were prepared via semi-chilling of small rods before been cast into ribbon using chill block melt spinner. Thermal aging studies followed by conductivity and microhardness tests were performed to follow the HSHC properties. Findings: It is found that the rapid solidification in the as-cast ribbon imposed combined solution extension and ultra-refinement of Cr rich phases. X-ray diffraction evidences suggest that the solid solution extension was up to 6wt%Cr. Lattice parameters determined confirmed the many folds extension of solid solution of Cr in Cu. Thermal aging studies of the cast ribbons indicated that peak aging treatments occurred in about twenty minutes. Peak aged hardness ranged from about 200 to well over 300Hv. The maximum peak aged hardness of 380Hv was obtained for alloy containing 6wt.%Cr but with conductivity of about 50%IACS. The best combined strength/conductivity was obtained for 4wt.%Cr alloy with hardness of 350HV and conductivity of 80% IACS. The high strengths observed are attributed to the increased volume proportion of semi-coherent Cr rich nano-sized precipitates that evolved from the supersaturated solid solution of Cu-Cr that was achieved from the high cooling rates imposed by the ribbon casting process Research limitations/implications: The rapid overaging of the high Cr concentration Cu-Cr alloy is still a cause for concern in optimising the process for reaching peak HSHC properties. It is still important to investigate a microstructural design to slow or severely restrict the overaging process. Originality/value: The optimum HSHC property reported here is a rare combination of high strength (>350Hv ~ 900MPa) and conductivity (50 – 80% IACS) found in metallic alloys.

13

Properties of the PZT Type Ceramics Admixed with Barium and Niobium

Zachariasz R., Bochenek D.

Archives of Metallurgy and Materials

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2009

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Vol. 54, iss. 4

895-902

EN

In this work a PZT type ceramics of the composition Pb0.90Ba0.10 (Zr0.53Ti0.47)0.95iNb0.04903 was obtained by a method of sintering simple oxides in the solid phase at high temperaturę. The X-ray examinations and examinations of a microstructure, an internal friction, dielectric and piezoelectric properties and a hysteresis loop of the ceramics obtained were madę. The electrophysical parameters of the ceramics obtained show a possibility to use that type of materiał as a bimorphic and ignition transducers, and high values of piezoelectric parameters and electric permittivity to build band-pass filters.

PL

W niniejszej pracy otrzymano piezoceramikę typu PZT o składzie Pb0.90Ba0.10 (Zr0.53 Ti0.47)0.95 Nb0.049O3 metodą spiekania prostych tlenków, w fazie stałej, w wysokiej temperaturze. Przeprowadzono badania rentgenowskie, mikrostrukturalne, tarcia wewnętrznego, właściwości dielektrycznych, piezoelektrycznych oraz pętli histerezy otrzymanej ceramiki. Elektrofizyczne paramenty otrzymanej ceramiki wskazują na możliwości zastosowania tego materiału jako bimorficzne i zapłonowe przetworniki, a wysokie wartości parametrów piezoelektrycznych i przenikalności elektrycznej umożliwiają jego wykorzystanie do budowy filtrów pasmowych.

14

Palladium nanocrystals and their properties

Czerwosz E., Dłużewski P., Kęczkowska J., Kozłowski M., Suchańska M., Wronka H.

Materials Science Poland

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2008

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Vol. 26, No. 1

119--125

EN

Films composed of Pd nanocrystals embedded in fullerene C60 matrix have been studied by TEM, AFM, UV-VIS absorption methods. Data on the structure of Pd nanocrystals was obtained from electron diffraction of selected areas and the size distribution for Pd nanocrystals was found from dark field TEM images. UV-VIS absorption spectra showed the shift of C60 characteristic bands connected with the ligand field effect. Electric characteristics were recorded for the initial dry film and film wetted by various liquid agents (benzene, ethanol, toluene).

15

Właściwości elektryczne materiałów polimerowych oraz możliwości ich korzystnych modyfikacji

Stefańczyk B., Mieczkowski P.

Warstwy, Dachy i Ściany

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2007

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nr 4

82-84

16

Shielding of electromagnetic fields by mono- and multi-layer fabrics made of metallic glasses with Fe and Co matrix

Nowosielski R., Griner S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

45-54

EN

Purpose: In the work, influence of chemical composition, as well as magnetic and electric properties on ability of metallic glass screens for shielding of not ionizing electromagnetic fields were analyzed. Design/methodology/approach: The groups of amorphous metallic alloys with iron, iron and nickel and cobalt matrix were selected for research. Samples of afore-mentioned metallic glasses were examined from the point of view of structure, magnetic, electric and mechanical properties. Findings: There is possibility of utilization of metallic amorphous materials for screens of not ionizing, electromagnetic fields especially in range of broad-band multi-layers screens with high efficiency of shielding in wide range of frequencies. Research limitations/implications: Very good magnetic properties and parallel low electric conductivity of metallic glasses are not enough for construction of multi-layer broadband screen. Therefore for constructing broadband screen, which would attenuate much better in wider range of frequencies, we should seek solutions in multi layers systems consisting of metallic glass fabrics, layers of large conductivity materials and nonmagnetic isolating layers. Problems of determining the number of layers, individual thickness of layer, materials in relation to optimum costs of multi-layers screen metallic glasses are unsolved. Practical implications: Attenuation of metallic glass screens show very high possiblilities of metallic glasses in solution of problem of shielding electromagnetic fields. Originality/value: There are two general direction of improvement of suppression efficiency of electromagnetic fields screens: research of new constructions of elastic screens, and investigation of new materials for screens join higher magnetic properties at high conductivity. In this second area, any possibilities exist in metallic nanomaterials in form of tapes and nanocomposites consisting magnetic powders with amorphous and nanocrystalline structure.

17

Cienkowarstwowe Magnetyczne Złącza Tunelowe i ich zastosowania

Wiśniowski P.

Przegląd Elektrotechniczny

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2006

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R. 82, nr 3

68-73

PL

Pracy dotyczy badań wpływu warstw buforowych magnetycznego złącza tunelowego typu zawór spinowy na istotne z punktu widzenia zastosowań spintronicznych parametry złącza takie jak: tunelowa magnetorezystancja, rezystancja na powierzchnię oraz pola przełączeń warstwy swobodnej i przytrzymanej. Zaprojektowano i wykonano magnetyczne złącza tunelowe o różnej strukturze i rodzaju warstw buforowych. Odpowiednie struktury warstw buforowych wygenerowały złącza o różnych własnościach mikrostrukturalnych (różne tekstury i szorstkości). Tekstura i szorstkość decydująco wpłynęły na własności elektryczne i magnetyczne złącz. Wpływ ten został zbadany poprzez pomiary zależności konduktancji złącz od temperatury i napięcia, charakterystyk prąd-napięcie, pętli histerezy magnetorezystancyjnej i magnetycznej.

EN

The influence of buffer layers of spin valve magnetic tunnel junctions on important, from the standpoint of spintronic applications, parameters of the junctions such as: tunneling magnetoresistance, resistance area product, and switching fields of free and pinned layers was investigated. Spin valve magnetic tunnel junctions with different buffer structures and type of buffer layers were design and fabricated. These buffers induced different microstructural properties (texture and roughness) in the junctions. Roughness and texture significantly influenced on the electrical and magnetic properties of the junctions. The influence was determined by measuring dependence of conductance on temperature and bias voltage, current-voltage characteristics, and magnetoresistance and magnetisation hysteresis loops.

18

Właściwości elektryczne materiałów kompozytowych srebro-wolfram-grafit i srebro-węglik wolframu-grafit o różnej zawartości grafitu

Stolarz S., Czepelak M.

Rudy i Metale Nieżelazne

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2005

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R. 50, nr 6

341-351

PL

Podano optymalne parametry wytwarzania materiałów kompozytowych srebro-wolfram-grafit i srebro-węglik wolframu--grafit zawierających 2 i 6 % grafitu metodami metalurgii proszków. Zbadano właściwości proszków oraz uzyskanych materiałów spiekanych. Dokonano oceny właściwości użytkowych badanych materiałów stykowych.

EN

Optimal parameters of fabrication of the silver-tungsten-graphite and silver-tungsten carbide-graphite type composite materials containing 2 and 6 % of graphite by powder metallurgy methods are given. Properties of the powders and of the obtained sintered materials have been examined. Applicational properties of the investigated contact materials have been assessed.

19

Electric properties of ionic metal alkanoate smectics with different dyes

Klimusheva G., Koval'chuk A., Sadovenko A., Bugaychuk S., Mirnaya T., Ishchenko A.

Opto-Electronics Review

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2004

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Vol. 12, No. 2

181-186

EN

The comparison analysis of electric properties of dye-doped ionic lyotropic liquid crystals before and after applying dc voltage was studied experimentally. The contributions both of the electrode – liquid crystal boundary layers and of electrochemical processes to electric effects are estimated.

20

Wybrane zagadnienia na wyznaczanie parametrów określających quasi-ustalone pole elektromagnetyczne w ciałach stałych

Kasperski Z.

Zeszyty Naukowe. Matematyka / Politechnika Opolska

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2002

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z. 18

85-95

PL

Sformułowane są zagadnienia fizyki matematycznej opisujące quasi-ustalone pole elektromagnetyczne w przewodzącym ciele stałym liniowym względem własności elektrycznych i magnetycznych.

EN

Problems of mathematical physics describing quasisteady electromagnetic field in electroconductive solids with linear electric and magnetic properties are formulated.