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71.
73.
令n=e_0+e_12+…+e_k2~k,其中e_j=0,1(j=0,…,k)表示自然数n的二进制展开式,N_0表示二进制展开式中项数为偶数的自然数的集合.分别给出了这个特殊集上素变数方程p_1+p_2+p_3~k=N和p_1+p_2~2+p_3~2+p_4~2=N解的个数的渐近公式. 相似文献
74.
《Physics and Chemistry of Liquids》2012,50(2):207-213
Excess molar polarization in the binary mixture of polar solutes (acetic acid, n-tributyl phosphate) in nonpolar solvents (benzene, tetrachloromethane, p-xylene) is evaluated with the help of our proposed equation. The results have been compared with those obtained from a previously proposed equation. It is observed that our proposed equation is more accurate to interpret the liquid structure and molecular association in the binary liquid mixtures. 相似文献
75.
Yuhiro Iwamoto Hiroshi Yamaguchi Xiao-Dong Niu 《Journal of magnetism and magnetic materials》2011,323(10):1378-1383
The magnetic body force in boiling two-phase temperature-sensitive magnetic fluid (TSMF) flow is known to effectively increase the driving force of magnetic fluid in a non-uniform magnetic field. Based on this mechanism, in the present study, a binary TSMF, which is a mixture of the TSMF and a low-boiling-saturation-temperature organic solution, is proposed to be used in a heat transport device to enhance its circulation. In order to see its performance in the heat transport device, the pressure difference at different heated temperatures, magnetic fields and inclination angles of the heating section are investigated experimentally and theoretically. Results showed that the driving force increases remarkably due to more gas phase appearing in the test fluid and the magnetization of it decreasing. At low magnetic field the driving force is enhanced greatly when the inclination angle is close to 60°, while at high magnetic field the driving force is remarkably enhanced due to the effect of the magnetic force in the inclination angle range from 0° to 30° and 60° to 90°. 相似文献
76.
Yizhak Marcus 《Monatshefte für Chemie / Chemical Monthly》2001,132(11):1387-1411
Summary. The Kirkwood-Buff integrals for 18 completely miscible aqueous co-solvent binary mixtures have been recalculated from thermodynamic data, and
the volume-corrected preferential solvation parameters derived from them are presented. Also presented are these latter quantities
for 15 additional such mixtures, for which the volume correction has not been applied previously. The self-interaction of
the water, the mutual interaction of the water and the co-solvent, and the self-interaction of the co-solvent at infinite
dilution derived from these integrals and parameters are then discussed. The systems studied include aqueous hydrogen peroxide,
methanol, ethanol, 1- and 2-propanol, 2-methyl-2-propanol, 2,2,2-trifluoroethanol, 1,1,1,3,3,3-hexafluoro-2-propanol, ethane-1,2-diol,
glycerol, 2-methoxyethanol (at 313 and 343 K), 2-ethoxyethanol, 2-butoxyethanol, 2-aminoethanol, N-methyl- and N,N-dimethyl-2-aminoethanol,
tetrahydrofuran, 1,4-dioxane, acetone, formic, acetic, and propanoic acids, piperidine, pyridine, acetonitrile, formamide,
N-methyl- and N,N-dimethylformamide, N-methylacetamide, N-methylpyrrolidin-2-one (at 303 K), hexamethyl phosphoric triamide,
dimethylsulfoxide, and tetramethylenesulfone (at 303 K).
Received January 10, 2001. Accepted (revised) February 20, 2001 相似文献
77.
Binary 3-point scheme, developed by Hormann and Sabin [Hormann, K. and Sabin, Malcolm A., 2008, A family of subdivision schemes with cubic precision, Computer Aided Geometric Design, 25, 41-52], has been modified by introducing a tension parameter which generates a family of C1 limiting curves for certain range of tension parameter. Ternary 3-point scheme, introduced by Siddiqi and Rehan [Siddiqi, Shahid S. and Rehan, K., 2009, A ternary three point scheme for curve designing, International Journal of Computer Mathematics, In Press, DOI: 10.1080/00207160802428220], has also been modified by introducing a tension parameter which generates family of C1 and C2 limiting curves for certain range of tension parameter. Laurent polynomial method is used to investigate the continuity of the subdivision schemes. The performance of modified schemes has been demonstrated by considering different examples along with its comparison with the established subdivision schemes. 相似文献
78.
Fu and Shen gave an upper bound on binary constant weight codes. In this paper, we present a new proof for the bound of Fu
and Shen and characterize binary constant weight codes meeting this bound. It is shown that binary constant weight codes meet
the bound of Fu and Shen if and only if they are generated from certain symmetric designs and quasi-symmetric designs in combinatorial
design theory. In particular, it turns out that the existence of binary codes with even length meeting the Grey–Rankin bound
is equivalent to the existence of certain binary constant weight codes meeting the bound of Fu and Shen. Furthermore, some
examples are listed to illustrate these results. Finally, we obtain a new upper bound on binary constant weight codes which
improves on the bound of Fu and Shen in certain case.
This research is supported in part by the DSTA research grant R-394-000-025-422 and the National Natural Science Foundation
of China under the Grant 60402031, and the NSFC-GDSF joint fund under the Grant U0675001 相似文献
79.
1 引言可转换债券以其独特的风险受益特性逐渐为投、融资者所接受并得到了广泛的欢迎.如今,无论在广度还是深度上,全球范围的可转债市场都已经发生了质的变化,并且日趋成熟和繁荣.中国的可转债市场在经历了十余年的沉寂之后,近两年也正进入一个高速发 相似文献
80.
Z. Y. Wu V. Jeyakumar A. M. Rubinov 《Journal of Optimization Theory and Applications》2007,133(1):123-130
We present sufficient conditions for the global optimality of bivalent nonconvex quadratic programs involving quadratic inequality
constraints as well as equality constraints. By employing the Lagrangian function, we extend the global subdifferential approach,
developed recently in Jeyakumar et al. (J. Glob. Optim., 2007, to appear; Math. Program. Ser. A, 2007, to appear) for studying bivalent quadratic programs without quadratic constraints, and derive global optimality conditions.
The authors are grateful to the referees for constructive comments and suggestions which have contributed to the final preparation
of the paper.
Z.Y. Wu’s current address: School of Information Technology and Mathematical Sciences, University of Ballarat, Ballarat, Victoria,
Australia. The work of this author was completed while at the Department of Applied Mathematics, University of New South Wales,
Sydney, Australia. 相似文献