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771.
Incomplete-Fusion-Fragmentation Model is used to analyze the multifragmentation of the projectile remnant in 600MeV/u Au+Au reaction.The theoretical resultsof the mass number,the excitation energy and the thermodynamical temperature of the projectile remnant agree well with experimental data.The backbending structure in the curve of temperature as a function of the excitation energy per nucleon,i.e. the evidence of liquid-gas phase transition,is reproduced and reasonably related to the decay modes phase transformation from dominance of the multifragmentation mode to the vaporization mode. 相似文献
772.
The increase of effective string tension as a result of the hard gluon kinks on a string is investigated using a parametrization form. In this form the effective string tension increasing with energies in hadron-hadron collisions is due to the mini-jet (gluon) production in the collisions. The data for the energy dependence of the strange quark suppression factor in hadron-hadron collisions are very well reproduced with this mechanism. Meanwhile, the experimental phenomena of approximate energy independence of the strange quark suppression factor in e+e- -annihilations are discussed. 相似文献
773.
M. Thamilselvan K. Premnazeer D. Mangalaraj Sa. K. Narayandass Junsin Yi 《Crystal Research and Technology》2004,39(2):137-142
A systematic investigation on the effect of substrate temperature on the structure, optical absorption and density of states of vacuum evaporated gallium monoselenide (GaSe) thin films is reported. The X‐ray diffraction analysis shows an occurrence of amorphous to polycrystalline transformation in the films deposited at higher‐temperature substrates (573K). The compositional analysis is made with Auger Electron Spectroscopy (AES). The thickness of the film (175nm) is measured by a multiple beam interferometery. Optical characteristics of the GaSe sample have been analyzed using spectrophotometer in the photon energy range of 1.0 ‐ 4 eV. The absorption mechanism has been recognized and the allowed indirect as well as forbidden direct transitions have been found. As‐deposited films show two indirect and allowed transitions due to spin‐orbit splitting of the valence band, as reported here for the first time. Low field conduction have enabled us to determine the density of states in amorphous and poly‐GaSe films. The amorphous and polycrystalline GaSe thin films have localized states density values of N (EF) = 1.686 × 1017 cm‐3 eV‐1 and 1.257 × 1015 cm‐3 eV‐1 respectively. The experimental results are interpreted in terms of variations in the density of localized states due to progressive decrease of the unsaturated bonds during deposition. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
774.
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776.
Maja Miletić Dragana Vuković Irena Živanović Ivana Dakić Ivan Soldatović Dejan Maletić Saša Lazović Gordana Malović Zoran Lj. Petrović Nevena Puač 《Central European Journal of Physics》2014,12(3):160-167
In numerous recent papers plasma chemistry of non equilibrium plasma sources operating at atmospheric pressure has been linked to plasma medical effects including sterilization. In this paper we present a study of the effectiveness of an atmospheric pressure plasma source, known as plasma needle, in inhibition of the growth of biofilm produced by methicillin resistant Staphylococcus aureus (MRSA). Even at the lowest powers the biofilms formed by inoculi of MRSA of 104 and 105 CFU have been strongly affected by plasma and growth in biofilms was inhibited. The eradication of the already formed biofilm was not achieved and it is required to go to more effective sources. 相似文献
777.
S. Mnasri N. Sfina S. Abdi-Ben Nasrallah J.-L. Lazzari M. Saïd 《Journal of magnetism and magnetic materials》2011,323(3-4):334-339
In this work, we carried out detailed investigation of a Cd1?xMnxTe/CdTe/Cd1?xMnxTe diluted magnetic semiconductor based quantum well. Our theoretical results are based on an accurate self-consistent resolution of the one-dimension Schrödinger and Poisson’s equations in the framework of the mean-field approximation for spin-up and spin-down orientations of carriers coupled via the sp–d exchange interaction. From the calculation of spin-dependent carrier densities for ferromagnetic and anti-ferromagnetic coupling, we evidence the spin-up and spin-down space separation for holes in quantum well for different values of band offsets. From deduced spin polarizations, we show that the CdTe region acts as a layer of spin rearrangement and spin reversal, respectively, in the ferromagnetic and anti-ferromagnetic coupling. The transmittance coefficients T+ and T? of injected spin-up and spin-down carriers are evaluated as a preliminary work to assess the spin-dependent currents in devices consisting of alternatively layers of non-magnetic and diluted magnetic semiconductors. 相似文献
778.
779.
A. O. Litinski Nguyen Thi Sa 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(3):549-556
A calculation scheme based on density functional theory generalized to the case of periodic structures is used to calculate the electron energy spectrum and the imaginary part of the permittivity of single-layer 2D structures based on silicon dioxide with the surface functional groups X ≡ OH, CH3, NH2, NO2, CHO, and COOH. The dependences of the energy corresponding to the energy-band edges, valence-band widths, and the positions of the characteristic peaks of the density of states on the degree of replacement by surface groups The peculiarities of the optical absorption bands in the absorbed photon energy region ?ω < 14 eV are revealed. 相似文献
780.
Xiong Rui Yang Honglei Peng Qiong Sa Baisheng Wen Cuilian Wu Bo Sun Zhimei 《Research on Chemical Intermediates》2017,43(9):5271-5282
Research on Chemical Intermediates - One typical two-dimensional transition metal dichalcogenide (TMDC) called the TcSe2 monolayer has been predicted to be a potential photocatalyst for water... 相似文献