Wyniki wyszukiwania - Biblioteka Nauki

1

Kepler's Orbital Motion Examined in Comparison with the Methods of Mechanics Developed by Stanescu and Tabacu

100%

Olszewski S.

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tom Vol. 16, No 3-4

293--299

EN

A new method developed by Stanescu and Tabacu to study the mechanics of a particle moving along a definite curve is compared with the well-known approach applied in calculating the Kepler's orbital motion. A particular effect of the rate of change of the kinetic energy of a body with respect to the change of a parameter defining the body position on the orbit is examined as an example. A comparison of the two methods shows only a slight numerical difference between the results of the Stanescu-Tabacu method and the traditional formalism. The components of the body acceleration are calculated along the orbit as an application of the new approach.

2

New kind of parameterization applied to the fermi surface of a crystalline solid. Part I: electron observables and curvature parameters examined on the surface

63%

Olszewski S. , Roliński T.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2009

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tom Vol. 13, No 1-2

99-115

EN

A magnetic field applied to a crystalline solid causes the electron states on the Fermi surface to circulate along the orbits located on the planes normal to the applied field. For a sufficiently weak field the separate orbits can cover the whole closed Fermi surface. A suitable parameterization of the states on the orbits should be done in a different way than a conventional parameterization applied for the electron states by Bloch. This new kind of parameterization becomes quite simple when the magnetic field is assumed to be directed parallel to one of the crystallographic axes. Computationally, a new description of the electron states on the Fermi surface becomes on many occasions more flexible in its use than the Bloch's one. The simplifications concern mainly an examination of the curvature parameters of the Fermi surface and extremal properties of the electron observables, for example that of electron velocity. Solely the states in the cubic crystal lattices were considered as examples.

3

New kind of parameterization applied to the Fermi surface of a crystalline solid. Part II: density of states and lengths of arcs calculated as a check of the theory

63%

Roliński T. , Olszewski S.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2009

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tom Vol. 13, No 1-2

117-131

EN

In order to check the validity of parameterization of electron states on the Fermi surfaces developed in the preceding paper, this parameterization is applied to the calculation of some definite crystal properties. The first property is the density of electron states versus energy in simple cubic and body-centered cubic crystal lattices, examined formerly on the basis of the Bloch parameterization of electron states by Jelitto; the other property is the length of some special arcs extended on the surfaces. The parameterizations of both approaches, that of the present paper and that developer on the basis of the Bloch states, are found to give results remaining in remarkable agreement.

4

Optical emission spectroscopy investigation of the low-power multispark plasma actuator

51%

Olszewski S. , Bondarenko P. , Kostenko S. , Komada P.

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2013

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tom Vol. 54, nr 8

54-57

PL

Jedną z istotnych metod kontrolowania przepływu aerodynamicznego przy powierzchni jest oddziaływanie na przepływ pulsującej plazmy. Dla rzeczywistych urządzeń wyładowczych, stosowanych w tego rodzaju zagadnieniach bardzo ważne jest zrozumienie jakie tryby zachowania plazmy z ciśnieniem atmosferycznym dają maksymalny efekt przy minimalnym zużyciu energii. Praktyczny aspekt pracy stanowią wyniki postępów w pracach nad skalowalnym wysokonapięciowym źródłem zasilania do wytwarzania wieloiskrowych wyładowań o dużej długości całkowitej. Podstawowy aspekt pracy stanowią rezultaty badań właściwości emisji plazmy dla quasi-stacjonarnych wioeloiskrowych wyładowań w ciśnieniu atmosferycznym.

EN

One of the important ways of controlling aerodynamic flow near the surface there is an impact to the flow of pulsating plasma. For a real discharge devices used in such problems it is very important to understand what modes maintain plasma of atmospheric pressure give maximum effect with minimum energy consumption. In the applied aspect of this work presents the results of the development of a scalable high-voltage power source to generate a multi-spark discharge with large total length. A fundamental aspect of this work presents the results of research of the plasma emission properties of quasi-stationary multi-spark discharge in atmospheric pressure.

5

Experimental research and modeling of plasma torch of direct-flow plasmatron with a transverse arc

51%

Olszewski S. , Denys A. , Skorokchod M. , Gromaszek K.

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2013

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tom Vol. 54, nr 8

73-75

PL

Źródła plazmy nierównowagowej w ciśnieniu atmosferycznym odgrywają coraz większą rolę w różnych technologiach plazmo-chemicznych. Obejmuje to: niszczenie toksycznych wielkocząsteczkowych związków w rozmowach wodnych, reforming węglowodorów z gazu syntezowego oraz tworzenie nanomateriałów z cieczy organicznych. W artykule przedstawiono wyniki badań eksperymentalnych i numerycznych jednego z oryginalnych źródeł plazmy tego rodzaju, opracowanych przez autorów niniejszej pracy i nazwanego plazmotronem o przepływie bezpośrednim. Przedstawiono analizę struktury palnika plazmowego tego źródła. Zaprezentowano wybrane cechy warunków formowania się wyładowania w tych urządzeniach. Wskazano pewne prawidłowości zachowań plazmy wytwarzanej przez plazmotron o przepływie bezpośrednim.

EN

Sources of non-equilibrium atmospheric pressure plasma play an increasingly central role in various plasma-chemical technologies. This is a destruction of toxic high-molecular compounds in aqueous solutions, this is reforming of hydrocarbons in synthesis gas, and the creation of nano-materials with organic liquids. This paper presents the results of numerical and experimental investigations one of the original sources of such a plasma, developed by the authors of this paper and named direct flow plasmotron. It is performed an analysis of the structure of the plasma torch of this source. It is shown some of the features of the formation conditions of the torch of this devices. It is disclosed some regularity of the behaviors of the plasma of direct-flow plasmatron.

6

Lead, cadmium, copper and zine concentrations in blood and hair of mothers of children with locomotor system malformations

38%

Popko J. , Olszewski S. , Hukalowicz K. , Markiewicz R. , Borawska M. H. , Szeparowicz P.

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nr 3

EN

Cadmium, copper and zinc concentrations in the blood and hair of 51 women after delivery of children with locomotor system malformations (Group I) and, as a control, 46 women who gave birth to healthy children (Group II) were different but none of the values were statistically significant. However, lead concentrations in the blood and the hair of women from the Group I (median: 109.63 μg/L and 1.31 μg/g) were notably higher than in Group II (median: 66.45 μg/L and 0.58 μg/g, respectively). Maternal lead concentrations in the blood of 17 women from Group I decreased to 60.73 μg/L, and in their hair to 1.20 μg/g after 12 months. We observed a significant correlation between lead concentrations and copper levels in the hair of the mothers.