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71.
Keith B. Oldham 《Journal of Solid State Electrochemistry》1997,1(1):36-44
This study concerns an infinite plane whose smoothness is marred by a single defect: either a groove or a ridge. The blemished
plane serves as an electrode supporting a diffusion-controlled steady-state process. By using a convenient coordinate transformation,
the local current density at all points on the surface is determined exactly. The results are found to confirm intuitive expectations.
Thus, compared with normal values on the plane remote from a groove, the electron transfer rate is diminished within the groove
but enhanced along its margins. Similarly, an abnormally large transfer rate is encountered high on the ridge but the rate
is subnormal on its lower flanks. The total current is demonstrated to be unchanged by the presence of the blemish.
Received: 27 September 1996 / Accepted: 11 March 1997 相似文献
72.
B. V. Derjaguin 《Progress in Surface Science》1992,40(1-4):240-251
A review is presented about research on surface forces and surface interactions conducted over the past half-century, with some emphasis on the pioneering contributions of the Department of Surface Phenomena at the Institute of Physical Chemistry of the USSR Academy of Sciences. 相似文献
73.
关于非齐次m阶马氏信源的渐近均分割性 总被引:4,自引:0,他引:4
本文研究非齐次m阶马氏信源的渐近均分割性,首先我们得到关于此种信源m 1元函数的一类强极限定理,作为推论,得到关于任意非齐次m阶马氏信源状态和熵密度的几个极限定理,最后得到一类非齐次m阶马氏信源的渐近均分割性。 相似文献
74.
75.
Jerzy Cioslowski 《Theoretical chemistry accounts》1992,81(4-5):319-327
Summary A new index, called the differential density matrix overlap (DDMO), is proposed for assessment of the electron correlation effects in atoms and molecules. DDMO can be easily calculated as the negative value of the correlation energy derivative with respect to the relative position of the occupied and virtual orbitals. DDMO is transparent to physical interpretation. It can serve as a tool for analyzing the accuracy of approximate electron correlation methods and the validity of the Hartree-Fock wavefunction as the zeroth-order approximation. The properties of DDMO are discussed using test calculations on 11 atoms and molecules as an example. 相似文献
76.
On the properties of solutions to the Goursat-Darboux problem with boundary and distributed controls
N. I. Pogodaev 《Siberian Mathematical Journal》2007,48(5):897-912
We consider a control system described by the Goursat-Darboux equation. The system is controlled by distributed and boundary controls. The controls are subject to the constraints given as multivalued mappings with closed, possibly nonconvex, values depending on the phase variable. Alongside the initial constraints, we consider the convexified constraints and the constraints whose values are the extreme points of the convexified constraints. We study the questions of existence of solutions and establish connections between the solutions under various constraints. 相似文献
77.
78.
The excess molar enthalpy of ternary mixture for 3-diethylaminopropylamine+heptane+cyclohexane were measured using a Calvet
microcalorimeter at 303.15 K.
Empirical equations, Redlich-Kister, Tsao-Smith, and Kohler and group contribution models, UNIFAC (modified version) and DISQUAC
have been applied. A reasonable representation of ternary data is obtained.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
79.
The paper is devoted to statistical nonparametric estimation of multivariate distribution density. The influence of data pre-clustering
on the estimation accuracy of multimodal density is analyzed by means of the Monte Carlo method. It is shown that the soft
clustering is more advantageous than the hard one. While a moderate increase in the number of clusters also increases the
calculation time, it considerably reduces the estimation error. 相似文献
80.