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101.
102.
Determination of equilibrium composition of C
x
H
y
O
z
N
t
plasmas out of thermodynamic equilibrium
Z. Koalaga 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,17(2):235-247
In this paper, we determine the composition of CxHyOzNt plasmas out of thermodynamic equilibrium using a more rigorous thermodynamic derivation of the Saha equation modified to
two-temperature plasma system proposed by Chen et al. The calculation is made for these plasmas in pressure range 0.1-1 MPa and for electron temperature range 5 000-30 000 K.
A great attention is given to the evolution of the major species such as hydrogen components (H, H2), carbon monoxide (CO) and electrons. We compared the results obtained with our previous experimental and theoretical studies;
the latter one has been carried out in equilibrium situation. We also compared our results with those given by the method
based on the minimization of the Gibbs free energy widely used in the literature.
Received 29 December 2000 and Received in final form 28 August 2001 相似文献
103.
P. A. Kendall N. J. Mason 《Journal of Electron Spectroscopy and Related Phenomena》2001,120(1-3):27-31
Electron energy loss spectroscopy (EELS) has been used to study the photo-absorption spectrum of trifluoromethyl sulphur pentafluoride (SF5CF3) for the first time. Comparison is made with the EELS spectrum of sulphur hexafluoride (SF6). The photolysis of the compound is discussed with relevance to estimated lifetimes in the atmosphere. It is estimated that the lifetime of SF5CF3 is of the order of 1000 years. 相似文献
104.
A formula expressing the statistical entropy of a lattice-gas model as a multiparticle correlation expansion is derived in the grand-canonical and in the canonical ensembles. The differences from the analogous expansion in the continuum case are elucidated. The Ising model in one dimension is discussed as a case study. 相似文献
105.
Judith R. Goodstein 《Physics in Perspective (PIP)》2001,3(3):271-313
Along with Enrico Fermi, Franco Rasetti played a key role in the rebirth of Italian physics in the 1920s and 1930s. In this
interview he talks about his experiments at Caltech on the Raman effect in 1928–1929, mountain climbing, his passion for bugs,
fossils, and flowers, and doing physics in Florence, Rome, Berlin-Dahlem, and Quebec. Rasetti also reminisces about the Rome
school of mathematics and other scientists he has known and worked with in Europe and in North America, including Robert and
Glenn Millikan, Lise Meitner, and O. M. Corbino. 相似文献
106.
107.
该设计解决了低温工程与低温技术等领域所使用的高纯度气体介质换热的要求,具有显著的经济效益和社会效益。其换热器是由四个管壳式热交换器串联组合而成,壳体呈窄矩形,换热管采用U形换热管,四个管壳式热交换器呈方阵置放在低温换热器筒体内。低温换热器采用的材料是0Cr18N i9/304,该种材料的透气性小、耐磨损、抗腐蚀能力强和性能稳定,防止了气体被污染。另外在低温下,考虑了材料的热胀冷缩所产生的应力,使应力能够自行消除,提高了它的密封性能,最终使低温换热器密封性能好,防止了气体被污染,保证了气体的高纯度。 相似文献
108.
Preparation of a two-state mixture of ultracold fermionic atoms with balanced population subject to the unstable magnetic field 下载免费PDF全文
《中国物理 B》2021,30(9):90303-090303
We report a novel method to prepare a mixture of ~(40)K Fermi gas having an equal population of the two ground magnetic spin states confined in an optical dipole trap, in the presence of an noisy quantization(magnetic) field. We realize the equal population mixture by applying a series of RF pulses. We observe the dependence of the population distribution between two spin states on the number of the applied RF pulses and find that the decoherence effects leading to the population fluctuations are overcome by the high number of RF pules. Our demonstrated technique can be potentially used in the precision measurement experiments with ultracold gases in noisy environments. 相似文献
109.
We present analytical formulae for the first and second derivatives of the Helmholtz free energy of non-relativistic ideal Fermi gas. Important thermodynamic quantities such as heat capacity, sound velocity, heat capacity ratio, and others are explicitly expressed through the derivatives. We demonstrate correct ideal Boltzmann gas and low-temperature Fermi gas asymptotes and derive corrections to thermodynamic functions for these limiting cases. Numerical computations of thermodynamic properties of ideal Fermi gas can be accurately performed using the developed freely available Python module ifg . 相似文献
110.
Noureddine Issaoui Najeh Rekik Brahim Oujia Marek J. Wójcik 《International journal of quantum chemistry》2010,110(14):2583-2602
In this article, we extend a previous work toward presenting a theoretical study of the effects of Fermi resonances and the fundamental anharmonic coupling parameter α between the high‐frequency mode and the H‐bond bridge. The model incorporates (i) both intrinsic anharmonicities of the fast mode (double well potential) and the H‐bond Bridge (Morse potential), (ii) strong anharmonic coupling theory, (iii) Fermi resonances by the aid of an anharmonic coupling between the fast mode and one or several harmonic bending modes, (iv) quadratic modulation of both the angular frequency and the equilibrium position of the X? …Y stretching mode on the intermonomer ? H… motions, and (v) the quantum direct (fast and bending modes) and indirect dampings (slow mode). The IR spectral density is obtained by Fourier transform of the autocorrelation function of the transition dipole moment operator of the X? H bond. The numerical calculation shows that Fermi resonances generate very complicated profiles with multisubstructure and also provide a direct evidence of Fermi resonances which were predicted to be a major feature of H‐bonds. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献