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61.
Ali Ghaffari 《Proceedings Mathematical Sciences》2007,117(2):177-183
In this paper, among other things, we state and prove the mean ergodic theorem for amenable semigroup algebras. 相似文献
62.
A Series of Exact Solutions of (2+1)-Dimensional CDGKS Equation 总被引:1,自引:0,他引:1
YANG Zong-Hang 《理论物理通讯》2006,46(11)
An algebraic method with symbolic computation is devised to uniformly construct a series of exact solutions of the (2 1)-dimensional Caudrey-Dodd-Gibbon-Kotera-Sawda equation. The solutions obtained in this paper include solitary wave solutions, rational solutions, triangular periodic solutions, Jacobi and Weierstrass doubly periodic solutions. Among them, the Jacobi periodic solutions exactly degenerate to the solutions at a certain limit condition. Compared with most existing tanh method, the method used here can give new and more general solutions. More importantly, this method provides a guideline to classify the various types of the solution according to some parameters. 相似文献
63.
Fritz Gesztesy Karl Unterkofler Rudi Weikard 《Transactions of the American Mathematical Society》2006,358(2):603-656
Combining theorems of Halphen, Floquet, and Picard and a Frobenius type analysis, we characterize rational, meromorphic simply periodic, and elliptic KdV potentials. In particular, we explicitly describe the proper extension of the Airault-McKean-Moser locus associated with these three classes of algebro-geometric solutions of the KdV hierarchy with special emphasis on the case of multiple collisions between the poles of solutions. This solves a problem left open since the mid-1970s.
64.
Tomasz Rolski 《Queueing Systems》1989,4(1):17-26
We study single server periodic queues in the day equilibrium conditions. The following characteristics of interest are considered at time of dayt: Vp(t)-the work load, Lp(t)-the number of customers and up(t)-the departure rate. We give relationships between E[Vp(t)], E[Lp(t)] and up(t). We also prove that E[Vp(t)] < and E[Lp(t)] < provided the second moment of the service time is finite. 相似文献
65.
廖伟雄 《广东微量元素科学》2002,9(4):69-70
介绍了一种室温下测定水中锰的方法,经检验,其显色反应可在短时间内完成,且色泽稳定,精密度和准确度均能达到分析要求。 相似文献
66.
A. V. Larin D. N. Trubnikov D. P. Vercauteren 《International journal of quantum chemistry》2003,92(1):71-84
Three hydrated aluminosilicate frameworks—LiABW, NaNAT, and BaEDI—are partly optimized with the periodic Hartree–Fock CRYSTAL95 code. In particular, we optimized the positions of the adsorbed water molecules including the positions of the framework cations (ABW, NAT) or part of the framework atomic positions (ABW). This allowed us to compare cation–water clusters in the gas and adsorbed states and discuss the influence of hydrogen bonding to the framework oxygen atoms or to the neighbor water molecules on the atomic properties (quadrupole coupling constant, anisotropy of electric field gradient) of the adsorbed water molecules. The LiBIK structure obtained from X‐ray diffraction is also considered to illustrate the hydrogen bonds occurring between adsorbed water molecules. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003 相似文献
67.
A.C. Marques R.M. Almeida A.R. Ramos E. Alves 《Journal of Sol-Gel Science and Technology》2004,32(1-3):287-291
Photosensitive organic-titania hybrid materials have been prepared from metal alkoxides and various organic ester compounds with
double bonds. The refractive index of the film increases with the decrease of the concentration of the organic ester compound, and the highest refractive index of 1.62 is obtained when 2-hydroxymethyl acrylate (HOA) is used as the organic ester and the molar ratio of HOA to Ti is 0.5. The material with the highest refractive index is exposed to femtosecond pulse using the multi-beam laser interference technique. After laser irradiation, the irradiated parts of the material are photopolymerized and periodic structures can be obtained by development of the unirradiated parts. In the case of laser irradiation of 120 J total energy for 5 min, the periodic structure obtained corresponds to 2D photonic crystal structure which is composed of two parts; the material with the highest refractive index and the air. 相似文献
68.
A Kinetic Evidence for the Nitroxyl Radicals Recycling Mechanism in the Photostabilizing Process of HALS 总被引:1,自引:0,他引:1
XiaoXuanLIU XingHongZHANG GuangGuoWU JianWenYANG ZhaoHuaZENG YongLieCHEN 《中国化学快报》2003,14(10):1085-1088
The photoinduced bulk polymerization of a reactive-hindered amine fight stabilizers(r-HALS), 4-acryloyl-2, 2, 6, 6-tetramethylpiperidinyl (ATMP), was performed at 80℃ by using a DPC technique. An unique periodic exponential attenuation-type oscillating curve was found when the polymerization was carried out in air, but this phenomenon was not found in nitrogen.It is supposed that this unique kinetic performance may be attributed to nitroxyl radicals that are produced in situ from the oxidation of ATMP. ATMP polymer with narrow polydispersity (d =1.03) can be obtained by photoinduced solution polymerization of ATMP. The signal detected in ESR may be assigned to the nitroxyl radicals in the matrix of ATMP polymer. Since this kind of recycling of nitroxyl radicals is well documented for the photostabilizing mechanism of HALS, the present results may serve as a kinetic evidence for this mechanism. 相似文献
69.
薄层扫描法测定冬眠过程中刺猬活性组织酶的周期变化冯金城(天津师范大学天津300074)孙金生(天津水产研究所天津300221)1前言为了跟踪观察刺猬在冬眠过程中体内乳酸脱氢酶的周期性变化,利用薄层扫描仪测定了其相关的组织同工酶的差异。实践证明,此法简... 相似文献
70.
The geometrical and energetical parameters of hydrogen fluoride and hydrogen chloride crystals are calculated using the periodic Hartree–Fock method with 6-31G and 6-31G(d,p) basis sets. The comparison of the stabilisation energies reveals that HCl crystals are about 75% less stable than HF crystals. The activation energy for collective proton movements are computed and discussed in view of data of isolated infinite chains. The barriers of 13.1 and 40.0 kcal mol−1 at 6-31G(d,p) level are found for HF and HCl crystals. 相似文献