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101.
Ivanov E. V. Ivanova N. G. Abrosimov V. K. Lebedeva E. Yu. 《Russian Chemical Bulletin》2001,50(12):2360-2365
The solubility of gaseous krypton in CO(NH2)2—CH3OH (CD3OH) and CO(ND2)2—CH3OD solutions with carbamide concentrations of up to 1.5 solvomolality units (0.026 mole fractions) was measured at 278, 288, 298, 308, and 318 K and at a partial gas pressure of 101325 Pa. The thermodynamic functions of dissolution (solvation) of krypton and the standard Setchenov coefficients were calculated. The solvation of Kr molecules increases upon deuterium substitution and with an increase in the temperature and carbamide concentration. In these solutions, specific contacts between the carbamide and methanol molecules play the predominant role. 相似文献
102.
K.?L.?YaoEmail author Q.?M.?Liu Z.?L.?Liu X.?W.?Liu G.?Y.?Sun 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,35(3):365-370
We introduce a solid-on-solid growth process which evolves by random deposition of dimers, surface diffusion, and evaporation
of monomers from the edges of plateaus. It is shown that the model exhibits a robust transition from a smooth to a rough phase.
The roughening transition is driven by an absorbing phase transition at the bottom layer of the interface, which displays
the same type of critical behavior as the pair contact process with diffusion 2A↦3A, 2A↦.
Received 14 October 2002 Published online 14 February 2003
RID="a"
ID="a"e-mail: Haye.Hinrichsen@physik.uni-wuppertal.de 相似文献
103.
E
N
T values were determined for 8 1-methyl-2-pyrrolidinone--solvent mixturesover the whole mole fraction range at 20, 30, and 50°C. The solvents used wereacetone, dimethyl sulfoxide, 2-propanol, 1,2-dichloroethane, water, 1,4-dioxane,benzyl alcohol, and hexamethylphosphoric triamide. The E
N
T values werepositive for the NMP + solvent systems, except for the NMP + water system. 相似文献
104.
H. B. Zhu H. X. Ge L. Y. Dong S. Q. Dai 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):103-108
Based on the Nagel-Schreckenberg (NaSch)
model of traffic flow, a modified cellular automaton (CA) traffic
model with the density-dependent randomization (abbreviated as the
DDR model) is proposed to simulate traffic flow. The fundamental
diagram obtained by simulation shows the ability of this modified
NaSch model to capture the essential features of traffic flow,
e.g., synchronized flow, metastable state, hysteresis and phase
separation at higher densities. Comparisons are made between this
DDR model and the NaSch model, also between this DDR model and the
VDR model. And the underlying mechanism is analyzed. All these
results indicate that the presented model is reasonable and more
realistic. 相似文献
105.
We explain the (non-)validity of close-to-equilibrium entropy production principles in the context of linear electrical circuits.
Both the minimum and the maximum entropy production principles are understood within dynamical fluctuation theory. The starting
point are Langevin equations obtained by combining Kirchoff’s laws with a Johnson-Nyquist noise at each dissipative element
in the circuit. The main observation is that the fluctuation functional for time averages, that can be read off from the path-space
action, is in first order around equilibrium given by an entropy production rate.
That allows to understand beyond the schemes of irreversible thermodynamics (1) the validity of the least dissipation, the
minimum entropy production, and the maximum entropy production principles close to equilibrium; (2) the role of the observables’
parity under time-reversal and, in particular, the origin of Landauer’s counterexample (1975) from the fact that the fluctuating
observable there is odd under time-reversal; (3) the critical remark of Jaynes (1980) concerning the apparent inappropriateness
of entropy production principles in temperature-inhomogeneous circuits. 相似文献
106.
严格的速率方程理论得到的总是非马尔可夫的,可是大部分实验都可以用马尔可夫的、即传统的速率常数基础上的反应动力学方程来描述.针对这一问题研究了电子转移过程中的马尔可夫/非马尔可夫特性.以最简单的两态电子转移反应为体系,以其在德拜溶剂中的严格动力学解为标定,采用光谱领域著名的Kubo运动谱窄化线型函数及其特性参数来描述电子转移过程中的马尔可夫/非马尔可夫本质.该马尔可夫特性参数是相干转移耦合与溶剂环境涨落相互影响共同作用的结果,以它为基础说明了大部分实验确实可以通过传统的速率方程来描述,而非马尔可夫速率过程最 相似文献
107.
Using the RTM/NEGF method, which is a first-principles calculation tool for the quantum transport through nanostructures between electrodes, we study the effects of atomic-scale contacts on the transport properties through single molecules. Electronic states and current-voltage (I-V) characteristics are investigated in various contact conditions with and without single molecules between electrodes. We find that similar nonlinear behaviors appear in the I-V characteristics. Such nonlinear behaviors are determined not only by the HOMO-LUMO electronic states of single molecules between electrodes, but also by the atomic-scale contact conditions. We show that the transitions from tunneling to ballistic regimes affect the I-V characteristics significantly. 相似文献
108.
John S. Lomas 《Magnetic resonance in chemistry : MRC》2013,51(1):32-41
The proton NMR spectra of several 1,2‐diols in benzene have been analysed so as to associate each magnetically nonequivalent proton with its chemical shift. The shifts and coupling constants of the OH and methylene protons of ethane‐1,2‐diol have been determined in a wide range of solvents. The conformer distribution and the proton NMR shifts of these 1,2‐diols in benzene have been computed on the basis of density functional theory. The solvent is included using the integral–equation–formalism polarizable continuum model implemented in Gaussian 09. Relative Gibbs energies for all stable conformers are calculated at the Perdew, Burke and Enzerhof (PBE)0/6‐311 + G(d,p) level, and shifts are calculated using the gauge‐including atomic orbital method with the PBE0/6‐311 + G(d,p) geometry but using the cc‐pVTZ basis set. Previous calculations on ethane‐1,2‐diol and propane‐1,2‐diol have been corrected and extended. New calculations on tert‐butylethane‐1,2‐diol, phenylethane‐1,2‐diol, butane‐2,3‐diols (dl and meso) and cyclohexane‐1,2‐diols (cis and trans) are presented. Overall, the computed NMR shifts are in good agreement with experimental values for the OH protons but remain systematically high for CH protons. Some results based on the Gaussian 03 solvation model are included for comparison. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
109.
L. I. Krishtalik 《Russian Journal of Electrochemistry》2008,44(1):43-49
Using own and literature data, the differences of real solvation energy for ferricenium and ferrocene in six solvents are found. These quantities are confronted with the calculated difference of the dielectric response energies plus nonelectrostatic energies for the redox couple. Such a comparison allows determining the sum of the surface and intraphase potentials. The comparison of these sums with the experimental values of the surface potential differences obtained by the measuring of Volta potentials allowed determining the differences of pre-existing intraphase potentials formed by solvent molecules on the ferrocene molecule. Thus, the intraphase potentials are evaluated for the first time, using an approach not based on the molecular-dynamic modeling. Using some approximations, the surface potentials of the studied solvents are found. 相似文献
110.
A path-integral Monte Carlo algorithm for the simulation of electrons solvated in polar liquids is briefly outlined, and results
are presented for the electron solvated in liquid water. 相似文献