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991.
Thermochemistry and Structure of Beryllium Chloride BeCl2 is dimorphous, with a transition point at 405°C. The transition enthalpy and transition entropy have been determined by solution calorimetry: ΔUH° = 2.9 kJmol?1 and ΔUS° = 9.7 JK?1mol?1. The previously known SiS2-type structure of BeCl2 is that of the high temperature phase. The structure of the phase stable at room temperature has been determined from single crystal data. a = 1 062.4(6) pm, c = 1 804(2) pm, I41/acd, Z = 32, R = 0.038 (Mg(NH2)2-type). The structure consists of P4O10-like [Be4Cl6Cl4/2]-units, connected by their terminal anions. 相似文献
992.
Inside a moving dielectric medium a wave perceives the matter as an effective gravitational field. The medium and its velocity field alter the way in which an electromagnetism field propagates. We propose an optical method for remote sensing of the velocity fields inside shear flows by angular scanning. 相似文献
993.
关于DRCE随机变量渐近分布性质的探讨 总被引:1,自引:0,他引:1
本文讨论了DRCE随机变量渐近正态收敛速度的一致上、下界,并对一类特殊的DRCE随机变量,讨论了其退化情况的不变原理。 相似文献
994.
In this paper, we extend the Hölderian invariance principle of Lamperti [6] to the case of partial-sum processes based on a triangular array of row-wise independent random variables. As an application, we obtain necessary and sufficient conditions for the almost sure (resp. in probability) weak Hölder convergence of partial-sum processes based on bootstrapped samples. 相似文献
995.
Mark Freidlin 《Journal of statistical physics》2006,122(2):333-349
We consider reaction-convection in a stationary incompressible flow which is close to a planar motion. Under certain conditions,
we introduce the notion of relative entropy for such a deterministic flow to describe the motion of the spot occupied by an
ingredient.
The work was supported in part by an NSF grant DMS0503950. 相似文献
996.
工程设计中约束规划熵方法的收敛性分析 总被引:1,自引:0,他引:1
极大熵方法在工程设计优化中得到成功的应用,但它的收敛性分析一直没有得到很好的解决.本文讨论了这个有意义的问题,在一般连续条件下解决了工程设计中的外点极大熵方法和内点极大熵方法的收敛性. 相似文献
997.
M. A. Prikhod’ko 《Theoretical and Mathematical Physics》2006,148(3):1251-1263
We calculate wave functions in the momentum representation for bound states in the relativistic Kozlov-Nikishin model. We
investigate the asymptotic behavior of entropy in the coordinate and momentum representations at various limiting transitions.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 148, No. 3, pp. 444–458, September, 2006. 相似文献
998.
999.
A. I. Sakhanenko 《Siberian Mathematical Journal》2006,47(6):1113-1127
We obtain estimates for the distributions of errors which arise in approximation of a random polygonal line by a Wiener process on the same probability space. The polygonal line is constructed on the whole axis for sums of independent nonidentically distributed random variables and the distance between it and the Wiener process is taken to be the uniform distance with an increasing weight. All estimates depend explicitly on truncated power moments of the random variables which is an advantage over the earlier estimates of Komlos, Major, and Tusnady where this dependence was implicit. 相似文献
1000.
Marie-Christine Costa Fethi Jarray Christophe Picouleau 《4OR: A Quarterly Journal of Operations Research》2006,4(1):73-85
This paper studies the days off scheduling problem when the demand for staffing fluctuates from day to another and when the
number of total workdays is fixed in advance for each employee. The scheduling problem is then to allocate rests to employees
with different days off policies: (1) two or three consecutive days off for each employee per week and (2) at least three
consecutive days off for each employee per month. For each one, we propose a polynomial time algorithm to construct a solution
if it exists.
Received: April 2005 / Revised version: October 2005
AMS classification:
60K25, 60K30 相似文献