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991.
三元无限稀释活度系数的实验测定 总被引:1,自引:0,他引:1
三元无限稀释活度系数的实验测定鲍坚斌,周秋红,李昂,韩世钧(浙江大学化学系,杭州,310027)关键词三元无限稀释活度系数,气提法,汽液平衡,液液平衡传统的无限稀释活度系数一般是指二元无限稀释活度系数,即(i为无限稀释单组分溶质,j为单组分溶剂),它... 相似文献
992.
A straightforward moving grid finite element method is developed to solve the one-dimensional coupled system of non-linear partial differential equations (PDEs) governing two- and three-phase flow in porous media. The method combines features from a number of self-adaptive grid techniques. These techniques are the equidistribution, the moving grid finite element and the local grid refinement/coarsening methods. Two equidistribution criteria, based on solution gradient and curvature, are employed and nodal distributions are computed iterativcly. Using the developed approach, an intermingle-free nodal distribution is guaranteed. The method involves examination of a single representative gradient to facilitate the application of moving grid algorithms to solve a non-linear coupled set of PDEs and includes a feature to limit mass balance error during nodal redistribution. The finite element part of the developed algorithm is verified against an existing finite difference model. A numerical simulation example involving a single-front two-phase flow problem is presented to illustrate model performance. Additional simulation examples are given in Part 2 of this paper. These examples include single and double moving fronts in two- and three-phase flow systems incorporating source/sink terms. Simulation sensitivity to the moving grid parameters is also explored in Part 2. 相似文献
993.
C. Caccamo 《Il Nuovo Cimento D》1993,15(2-3):435-442
Summary The phase stability of ionic multicomponent fluids is investigated through the Mean Spherical Approximation in the framework
of the well-known Restricted Primitive Model of electrolytes. Phase stability conditions are obtained by studying the behaviour
of the isothermal compressibility which diverges at the liquid-vapour spinodal. The model parameters are chosen so as to represent
charged colloidal solutions with a big polyion and small counterions; the case in which a third neutral-particle species is
present, possibly modelling the solvent, is also investigated. The MSA predictions turn out to be in good qualitative agreement
with previous hypernetted-chain calculations for the same system; the simplicity and flexibility of the theory also allows
a determination of the stability conditions for various assignments of the physical parameters which can reasonably mimic
realistic configurations of charged colloidal solutions. Possible extensions and improvements of the present theoretical study,
and a systematic procedure to assess its predictions for practical applications, are also shortly discussed.
In honour of Prof. Fausto Fumi on the occasion of his retirement from teaching. 相似文献
994.
995.
Monitoring of multiphase flow is a process that has been established over several decades. This paper demonstrates the use of Acoustic Emission (AE) technology to detect and monitor moving water and water–sand droplets in a horizontal pipe. The experimental investigation considered two types of droplets, water and water–sand with average droplet volumes ranging from 1 ml to 5 ml. The experimental findings show good correlation between AE energy, droplet volume and the superficial gas velocity (VSG). 相似文献
996.
Weak and Strong Time Consistency in a Differential Oligopoly Game with Capital Accumulation 总被引:1,自引:0,他引:1
We illustrate a differential oligopoly game with capital accumulation where the accumulation dynamics of productive capacity
is modelled à la Ramsey. The model is solved under the open-loop information structure, to show that it admits an open-loop
Nash equilibrium which is indeed a degenerate feedback one and therefore strongly time consistent, even if, by construction,
the problem under consideration is not a linear state game.
We thank George Leitmann, Massimo Marinacci, Daniele Ritelli, Arsen Palestini and two anonymous referees for very useful comments
and suggestions. 相似文献
997.
The most stable conformer of chiral 1-(2-fluorophenyl)-1-ethanol is stabilized by a O–H?π interaction and it is at least 1 kcal/mol more stable than the remaining conformers. This is the result of a free jet millimeter–wave absorption spectroscopy investigation of the rotational spectra of the most abundant and O–d isotopic species. 相似文献
998.
Noah D. Stein Asuman Ozdaglar Pablo A. Parrilo 《International Journal of Game Theory》2008,37(4):475-504
In this paper, we study nonzero-sum separable games, which are continuous games whose payoffs take a sum-of-products form.
Included in this subclass are all finite games and polynomial games. We investigate the structure of equilibria in separable
games. We show that these games admit finitely supported Nash equilibria. Motivated by the bounds on the supports of mixed
equilibria in two-player finite games in terms of the ranks of the payoff matrices, we define the notion of the rank of an
n-player continuous game and use this to provide bounds on the cardinality of the support of equilibrium strategies. We present
a general characterization theorem that states that a continuous game has finite rank if and only if it is separable. Using
our rank results, we present an efficient algorithm for computing approximate equilibria of two-player separable games with
fixed strategy spaces in time polynomial in the rank of the game.
This research was funded in part by National Science Foundation grants DMI-0545910 and ECCS-0621922 and AFOSR MURI subaward
2003-07688-1. 相似文献
999.
L.Q. Lobo I.M.A. Fonseca A.G.M. Ferreira A.M.P. Senra 《The Journal of chemical thermodynamics》2006,38(12):1532-1538
The equilibrium pressure of ternary mixtures of {x1CH3F + x2HCl + x3N2O} covering the entire composition range has been measured at temperature of 182.33 K by the static method. The system exhibits a minimum pressure for the binary {x1CH3F + x2HCl}. The molar excess Gibbs free energy has been calculated from the experimental equilibrium pressure. For the equimolar mixture . The (p, x, y) surface for the ternary system and the corresponding curves for the three constituent binary mixtures obtained from the Peng-Robinson equation of state are in agreement with the experimental data. 相似文献
1000.
Bakirci H Koner AL Schwarzlose T Nau WM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(18):4799-4807
The pD dependence of the complexation of p-sulfonatocalix[4]arene (CX4) with the azoalkanes 2,3-diazabicyclo[2.2.1]hept-2-ene (1), 2,3-diazabicyclo[2.2.2]oct-2-ene (2), 2,3-diazabicyclo[2.2.3]non-2-ene (3), and 1-methyl-4-isopropyl-2,3-diazabicyclo[2.2.2]oct-2-ene (4) in D(2)O has been studied. The pD-dependent binding constants, determined by (1)H NMR spectroscopy, were analyzed according to a seven-state model, which included the CX4 tetra- and penta-anions, the protonated and unprotonated forms of the azoalkanes, the corresponding complexes, as well as the complex formed between CX4 and the deuteriated hydronium ion. The variation of the UV absorption spectra, namely the hypsochromic shift in the near-UV band of the azo chromophore upon protonation, was analyzed according to a four-state model. Measurements by independent methods demonstrated that complexation by CX4 shifts the pK(a) values of the guest molecules by around 2 units, thereby establishing a case of host-assisted guest protonation. The pK(a) shift can be translated into improved binding (factor of 100) of the protonated guest relative to its unprotonated form as a result of the cation-receptor properties of CX4. The results are discussed in the context of supramolecular catalytic activity and the pK(a) shifts induced by different types of macrocyclic hosts are compared. 相似文献