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101.
Hideki Takayasu Misako Takayasu Astero Provata Greg Huber 《Journal of statistical physics》1991,65(3-4):725-745
We study a generalized aggregation process in which charged particles diffuse and coalesce randomly on a lattice. For one-dimensional and mean-field models, we show that there exists a statistically-invariant steady state when randomly charged particles are continuously injected. The steady-state charge distribution obeys a power law with the exponent depending both on the type of the injection and on the spatial dimension. The response of the system to a perturbation (i.e., relaxation) is characterized by either a power law decay (t
–
,1) or a compressed exponential decay [exp(–t
),>1]. 相似文献
102.
Norman O. Smith 《Journal of solution chemistry》1994,23(4):521-539
A method of finding the activity coefficients of salts, anhydrous or hydrated, in binary solid solutions, described in an earlier paper as it applies to continuous series, has been applied to discontinuous series. The salts must differ with respect to only one ion. The method requires isothermal distribution data for equilibria between liquid (aqueous) and solid solutions in the ternary system consisting of the two salts and water. The following salt pairs were used for illustration: K(I/Br) at 0, 15, 25, 35, and 50°C., (NH4/K)SCN at 0, 30, 60, and 90°C., (K/Tl)C103 at 10°C., and (NH4/K)SO3NH2, (NH4/K)Br, (Mg/Co)SO4-7H2O, and (Mn/Cu) SO4.n H2O-all at 25°C. Two kinds of behavior were noted and treated differently: systems in which the two series have the same, and those in which they have different crystal lattices. For two salts, A and B, which have the same lattice, and whose rational activity coefficients, f
A
and f
B
, can be described by 2-suffix Margules equations (regular solutions), lnf
A
=Bsx
B
2
and lnf
B
=Bsx
A
2
to be partially miscible, Bs>2, but this requirement does not apply if the lattices are different. In each series, distribution constants for the equilibria were also determined. Where possible, the calculated activities of the salts or the Gibbs excess energies of the solid solutions were compared with values reported by others who determined them by other methods. All the salt pairs studied show slight or strong positive deviations from ideality. 相似文献
103.
104.
The third law of thermodynamics, in the sense that the entropy per unit volume goes to zero as the temperature goes to zero, is investigated within the framework of statistical mechanics for quantum and classical lattice models. We present two main results: (i) For all models the question of whether the third law is satisfied can be decided completely in terms of ground-state degeneracies alone, provided these are computed for all possible boundary conditions. In principle, there is no need to investigate possible entropy contributions from low-lying excited states, (ii) The third law is shown to hold for ferromagnetic models by an analysis of the ground states.Dedicated to Pierre Résibois. Work supported in part by NSF grant PHY-7825390 A01. 相似文献
105.
Giuseppe Maria Coclite 《偏微分方程通讯》2013,38(8):1253-1272
We consider a shallow water equation of the Camassa–Holm type, which contains nonlinear dispersive effects as well as fourth order dissipative effects. We prove that as the diffusion and dispersion parameters tend to zero, with a condition on the relative balance between these two parameters, smooth solutions of the shallow water equation converge to discontinuous weak solutions of a scalar conservation law. The proof relies on deriving suitable a priori estimates together with an application of the compensated compactness method in the L p setting. 相似文献
106.
Although the numerical results suggest the optimal convergence order of the two-grid finite element decoupled scheme for mixed Stokes–Darcy model with Beavers–Joseph–Saffman interface condition in literatures, the numerical analysis only gets the optimal error order for porous media flow and a non-optimal error order that is half order lower than the optimal one in fluid flow. The purpose of this paper is to fill in the gap between the numerical results and the theoretical analysis. 相似文献
107.
In this paper, we are concerned with the behavior of shock waves in a 2 × 2 balance law with discontinuous source terms. We obtain the existence of a local shock wave solution of this problem and deduce that the discontinuous source terms create a weak discontinuity in this solution. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
108.
《Electrophoresis》2017,38(3-4):417-428
The mechanisms underlying the aberrant growth and interactions between cells are not understood very well. The pre‐B acute lymphoblastic leukemia cells directly obtained from an adult patient grow very poorly or do not grow at all at low density (LD), but grow better at high starting cell density (HD). We found that the LD ALL3 cells can be stimulated to grow in the presence of diffusible, soluble factors secreted by ALL3 cells themselves growing at high starting cell density. We then developed a biochemical purification procedure that allowed us to purify the factor(s) with stimulatory activity and analyzed them by nanoliquid chromatography‐tandem mass spectrometry (nanoLC‐MS/MS). Using nanoLC‐MS/MS we have identified several proteins which were further processed using various bioinformatics tools. This resulted in eight protein candidates which might be responsible for the growth activity on non‐growing LD ALL3 cells and their involvement in the stimulatory activity are discussed. 相似文献
109.
In this paper, a simultaneous canonical form of a pair of rectangular complex matrices is developed. Using this new tool we give a necessary and sufficient condition to assure that the reverse order law is valid for the weighted Moore–Penrose inverse. Additionally, we characterize matrices ordered by the weighted star partial order and adjacent matrices as applications. 相似文献
110.
Uniform spreading of oil on solid surfaces is important in many processes where proper lubrication is required and this can be controlled using surfactants. The role of oil–solid interfacial self-assembled surfactant structure (SASS) in oil spreading is examined in this study for the case of hexadecane-surfactant droplet spreading on a flat horizontal copper surface, with triphenyl phosphorothionate surfactants having varying chain lengths (0 to 9). It is shown that the frictional forces (FSASS) as determined by the SASS regulate droplet spreading rate according to surfactant chain length; surfactants with longer chains led to higher reduction in the spreading rate. The extent of such forces, FSASS, depends on the surfactant density of the evolving SASS, and specific configuration the evolving SASS exhibit as per the orientations of the surfactant chains therein. Thus, FSASS = [k1 + k2(t)] Γδ(t), where Γδ(t) is the surfactant adsorption density of SASS at time ‘t’ during evolution, and, k1 and k2(t) are the force coefficients for Γδ(t) and orientations (as a function of spreading time) of the surfactant chains respectively. As a SASS evolves/grows along with adsorption of surfactants at the spreading induced fresh interface, the k1Γδ(t) component of FSASS increases and contributes to reduction in the net spreading force (S). With a decrease in the net spreading force, the existence of a cross-over period, during which the transition of the spatial dynamics of the chains from disordered to realignment/packing induced ordered orientation occurs, has been inferred from the FSASS vs. chain length relationships. Such relationships also suggested that the rate of realignment/packing is increased progressively particularly due the realignment/packing induced decrease in the net spreading force. Therefore, the realignment process is a self-induced process, which spans a measurable period of time (several minutes), the cross-over period, during which the net spreading force decreases essentially due to such self-induced process. 相似文献