P. Zukowski

Magnetic Anisotropy in Bicomponent Self-Assembled Ni and Ni-Pd Nanowires Studied by Magnetic Resonance Spectroscopy

Self-ordered arrays of Ni, Ni(50)Pd(50), and Ni(78)Pd(22) nanowires were synthesized by simultaneous electrochemical deposition of Ni and Pd components into porous templates of anodic aluminum oxide using alternating current. This paper is focused on the interplay of structure and chemical composition of Ni and Ni-Pd bicomponent nanowires arrays and the peculiarities of its magnetic anisotropy.

Capacitive properties of nanocomposite (FeCoZr)x(PZT)(100-x) produced by sputtering with the use of argon and oxygen ions beam

The paper established that, the hopping mechanism of the charge exchange for the (FeCoZr)64.4(PZT)35.6 nanocomposite and the additional polarization of tested sample occurs. As frequency increases two frequency areas where capacitance decreases can be observed. Correlation between the conductivity increase and the capacitance decrease has been observed for the both stages of their variability. Voltage resonance phenomenon for the studied material was observed. The zero crossing in the frequency dependence of phase difference transition is accompanied with this phenomenon, which is reflected by a sharp minimum in the capacitance versus frequency characteristics.

Analysis of AC conductivity in wet oil impregnated insulating paper

In paragraph are presented the results of research based on the AC conductivity of the wet oil-impregnated insulating paper, depending on the moisture content and temperature of the samples. This is a new experimental method, which converts the results from the FDS to the reference temperature of 293.15 K (20 ° C). Takes account of the activation energy for conduction and relaxation time.

Diagnostics and measurement of the gasoline engines injection system

The paper presents the electronic fuel injection system research results, which can be used in diagnostic issues. Have been described the construction and operation of a typical fuel injection system and analysed its electronic part. It has also been proposed method for the detection of the injector malfunction, based on the analysis of differential current characteristic. Have been shown differences in the electrical parameters of the individual fuel injectors, which can be corrected e.g. by suitable self-learning algorithms. Słowa kluczowe: elektroniczny wtryskiwacz paliwa, diagnostyka, pomiar, charakterystyka prądu różnicowego.

Fabrication and characterization of transparent tin dioxide films with variable stoichiometric composition

Tin dioxide lms with variable stoichiometric composition were fabricated by means of dc magnetron sputtering followed by a 2-stage annealing process. The structural and electrical properties of tin dioxide lms were investigated by means of the Raman spectroscopy and impedance spectroscopy, respectively. It was found that crystallinity and grain size of tin dioxide lms increase with the increasing annealing temperature. The most conductive samples were obtained at the annealing temperature 375 ◦C. Increasing of the impedance of lms annealed at higher temperatures is explained by decrease of the concentration of oxygen vacancies.

Calculation of the ultimate efficiency of p-n-junction solar cells taking into account the semiconductor absorption coefficient

A model based on the famous model of Shockley–Queisser for calculation the ultimate efficiency of solar cells has been proposed, taking into account the dependence of the semiconductor absorption coefficient on the band-gap and on the energy of the incident photons. The dependence of the ultimate efficiency of solar cells on thickness of the absorption layer was found out for homogeneous solar cells. Streszczenie. Opierając się na znanym modelu Shockley`a–Queisser`a do obliczeń maksymalnej sprawności ogniw słonecznych, zaproponowano model biorąc pod uwagę zależność współczynnika absorpcji półprzewodników od pasma wzbronionego oraz energii padających fotonów. Określono zależność maksymalnej sprawności ogniw słonecznych od grubości warstwy absorpcyjnej dla jednorodnych ogniw słonecznych. (Obliczanie maksymalnej sprawności złącza p-n ogniw słonecznych na podstawie współczynnika absorpcji półprzewodników).

Diagnostics of transformer with insulation oil-paper

The article deals with method describing the state of transformer insulation. By the determining its state is acquainted return voltage measurement and measurement the insulation resistance of windings. Return measurement voltage method is wide state specifying method which is not set in standards but in many cases is a method which is determining a clear and exact result. The results have mainly shows moisture content, content of conductive impurities in oil and degree of aging of paper insulation impact. Słowa kluczowe: napięcie powrotne, rezystancja izolacji, wskaźnik polaryzacji, transformator.

Moisture level content analysis in oil impregnated pressboard used in power transformers

The article presents the results of research based on the DC electrical conductivity of wet paper depending on the moisture content and temperature of the samples. The change of moisture content does not change the activation energy of conductivity. The conductivity is performed by the hopping mechanism between the nearest possible holes which are formed in the material with nanodrops of water by the plotting of theoretical dependence that accurately describes the dependence of the conductivity of the water content and temperature. Medium size of nanodrops was about 1.5 nm, and the composition contains about 220 molecules of water.