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131.
E.R. Ionita 《Applied Surface Science》2009,255(10):5448-5452
A small size radiofrequency plasma jet source able to produce cold plasma jets at atmospheric pressure is presented. The surface modification of polyethylene terephtalate, polyethylene and polytetrafluorethylene foils is performed by using a scanning procedure. The contact angle measurements reveal that the treatment leads to hydrophilicity increase. The roughening of surface, specific to each material is noticed. A significant improvement of adhesion is obtained as result of atmospheric plasma treatments. 相似文献
132.
A. A. Nikiforov E. A. Maslov N. K. Skripnikova O. G. Volokitin 《Thermophysics and Aeromechanics》2009,16(1):149-153
Herein the fundamentally new unit for production of silicate refractory melts with the use of high-concentrated heat fluxes
is considered. Mathematical model describing temperature fields in skull layer in the process of the plasma flow interaction
with the particles of refractory silicate material has been developed. Typical numerical results of temperature distribution
in various sections of the skull layer are presented. Numerical and experimental data have been compared, and their fair agreement
is obtained.
The work was financially supported by RF President (Grant No. MK 1110.2008.8). 相似文献
133.
H. Nowakowska M. Jasiński J. Mizeraczyk 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(2):511-518
We present results from simulations of 2D distributions of the electromagnetic field inside a waveguide-based axial-type microwave
plasma source (MPS) used for hydrogen production via methane reforming. The studies are aimed at optimization of discharge
processes and hydrogen production. We derive equations for determining electromagnetic field distributions and next determine
the electromagnetic field distributions for two cases – without and with plasma inside the MPS. For the first case, we examine
the influence of the length of the inner conductor of the coaxial line on electromagnetic field distributions. We have obtained
standing wave patterns along the coaxial line and found resonances for certain positions of the coaxial line inner conductor.
For the case with plasma inside the MPS, we perform calculations assuming that distributions of plasma parameters are known.
Simulations are done for several values of maximum electron density. We have found that for values of electron density greater
than strong skin effect in the plasma is observed. Consequently, plasma may be treated as an extension of the inner conductor
of the coaxial line. We have used FlexPDE software for the calculations. 相似文献
134.
M. Jasiński M. Dors J. Mizeraczyk 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(2):179-183
In this paper, results of hydrogen production via methane pyrolysis in the atmospheric pressure microwave plasma with CH4 swirl are presented. A waveguide-based nozzleless cylinder-type microwave plasma source (MPS) was used to convert methane
into hydrogen. The plasma generation was stabilized by a CH4 swirl having a flow rate of 87.5 L min-1. The absorbed microwave power was 1.5–5 kW. The hydrogen production rate and the corresponding energy efficiency were 866 g
(H2) h-1 and 577 g (H2) kWh-1 of microwave energy absorbed by the plasma, respectively. These parameters are better than our previous results when nitrogen
was used as a swirl gas and much better than those typical for other plasma methods of hydrogen production (electron beam,
gliding arc, plasmatron). 相似文献
135.
K. Nowakowska-Langier L. Jakubowski E. O. Baronova K. Czaus M. Rabinski M. J. Jakubowski 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(2):377-382
This study reports the results of a pilot experiment concerning observations of extreme ultraviolet emission from plasma produced
by the capillary discharges. A few kA current was applied across the gas-filled alumina capillary (1 mm diameter and 8 mm
long) to generate radiation in the EUV region (12–63 nm). Spectroscopic studies were carried out by means of a XEUV spectrometer
which was upgraded for special lithography purposes. The results obtained from the EUV spectroscopic measurements provided
information about the radiation processes from xenon and argon plasma and testifies that given capillary is an effective source
of EUV emission. Additionally we showed a simulation which describes plasma dynamics parameters and dynamics of various ionization
stages in capillary discharge. Our computer simulation confirmed the presence of ions, which spectra was registered in the
experiment. 相似文献
136.
137.
Piotr Kirszensztejn Robert Przekop Agnieszka Tolińska Ewa Ma?kowska 《Chemical Papers》2009,63(2):226-232
In the, at present, unstable fuel market, much attention is devoted to alternative technologies for fuel production and development
of alternative products of the petrochemical industry. One of the prospective sources of fuel and alternative petrochemical
products is biomass, and the use of oil plants is one of the possibilities. This paper reports on a possible conversion of
rapeseed oil produced in Poland into intermediate hydrocarbon fractions by pyrolysis combined with parallel catalytic conversion.
The products were analysed by gas chromatography coupled with a mass detector. The process was performed in a fixed-bed reactor
and was monitored by FTIR and 1H NMR. Depending on the catalysts applied, the products contained: water, carbon oxides, hydrogen, aliphatic or aromatic hydrocarbons
accompanied by some amount of C2-C5 hydrocarbons formed during the cracking process.
Presented at the 35th International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 26–30 May
2008. 相似文献
138.
Wout De Nolf Jakub Jaroszewicz Roberto Terzano Ole Christian Lind Brit Salbu Bart Vekemans Koen Janssens Gerald Falkenberg 《Spectrochimica Acta Part B: Atomic Spectroscopy》2009,64(8):775
The performance of a combined microbeam X-ray fluorescence/X-ray powder diffraction (XRF/XRPD) measurement station at Hamburger Synchrotronstrahlungslabor (HASYLAB) Beamline L is discussed in comparison to that at European Synchrotron Radiation Facility (ESRF) ID18F/ID22. The angular resolution in the X-ray diffractograms is documented when different combinations of X-ray source, optics and X-ray diffraction detectors are employed. Typical angular resolution values in the range 0.3–0.5° are obtained at the bending magnet source when a ‘pink’ beam form of excitation is employed. A similar setup at European Synchrotron Radiation Facility beamlines ID18F and ID22 allows to reach angular resolution values of 0.1–0.15°. In order to document the possibilities and limitations for speciation of metals in environmental materials by means of Hamburger Synchrotronstrahlungslabor Beamline L X-ray fluorescence/X-ray powder diffraction setup, two case studies are discussed, one involved in the identification of the crystal phases in which heavy metals such as chromium, iron, barium and lead are present in polluted soils of an industrial site (Val Basento, Italy) and another involved in the speciation of uranium in depleted uranium particles (Ceja Mountains, Kosovo). In the former case, the angular resolution is sufficient to allow identification of most crystalline phases present while in the latter case, it is necessary to dispose of an angular resolution of ca. 0.2° to distinguish between different forms of oxidized uranium. 相似文献
139.
In this paper, the ‘source generation’ procedure (SGP) proposed by Hu and Wang [X.B. Hu, H.Y. Wang, Construction of dKP and BKP equation with self-consistent sources, Inverse Problems 22 (2006) 1903-1920] is utilized to derive Lie symmetries of bilinear soliton equations with self-consistent sources (SESCS) such as KPESCS, BKPESCS, and differential-difference KPESCS. Furthermore, it is shown that these Lie symmetries constitute generators of the corresponding Lie symmetry algebras. 相似文献
140.