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91.
In this paper,we give some interesting results concerning the entire function f(z) sharing a small function a CM with its difference operators or shifts. 相似文献
92.
本文对PP/[C14MIM]Br体系的熔融过程和对CO2的吸收, 以及[C14MIM]Br在PP基体中的分散状态进行了研究, 并初步考察了[C14MIM]Br对PP发泡性能的影响. 相似文献
93.
M. Ricker J. Bachteler H.-R. Trebin 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,23(3):351-363
In quasicrystals, there are not only conventional, but also phason displacement fields and associated Burgers vectors. We
have calculated approximate solutions for the elastic fields induced by two-, three- and fivefold straight screw- and edge-dislocations
in infinite icosahedral quasicrystals by means of a generalized perturbation method. Starting from the solution for elastic
isotropy in phonon and phason spaces, corrections of higher order reflect the two-, three- and fivefold symmetry of the elastic
fields surrounding screw dislocations. The fields of special edge dislocations display characteristic symmetries also, which
can be seen from the contributions of all orders.
Received 21 February 2001 and Received in final form 27 June 2001 相似文献
94.
M. Hausmann J. Stadlmann F. Attallah K. Beckert P. Beller F. Bosch H. Eickhoff M. Falch B. Franczak B. Franzke H. Geissel Th. Kerscher O. Klepper H.-J. Kluge C. Kozhuharov Yu.A. Litvinov K.E.G. Löbner G. Münzenberg N. Nankov F. Nolden Yu.N. Novikov T. Ohtsubo T. Radon H. Schatz C. Scheidenberger M. Steck Z. Sun H. Weick H. Wollnik 《Hyperfine Interactions》2001,132(1-4):289-295
A novel method for mass measurements of short-lived exotic nuclides is presented. Exotic nuclides were produced and separated
in flight at relativistic energies with the fragment separator (FRS) and were injected into the experimental storage ring
(ESR). Operating the ESR in the isochronous mode we performed mass measurements of neutron deficient fragments of 84Kr with half-lives larger than 50 ms. However, this experimental technique is applicable in a half-life range down to a few
μs. A mass resolving power of 110000 (FWHM) has been achieved. Results are presented for the masses of 68As, 70,71Se and 73Br.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
95.
A type of system, in which the specific volume can be divided into several parts according to its Hamiltonian, has been obtained in a grand ensemble. The main character of such a system is that its Hamiltonian is absolutely separable. We also discuss the partial specific volume contributed by thermoelectrons in metals under a free-interaction approximation, and the corresponding Wu-Jing parameter is obtained as a simple example. 相似文献
96.
The effect of divalent cation substitution on the structure and magnetic properties of La1.2Sr1.8-xCaxMn2O7 (x = 0-0.900) is investigated in this paper. Partly replacing divalent cation Sr2+ by Ca2+ ions results in the weakening and then disappearance of long-range ferromagnetic ordering, and the formation of spin canting and low-temperature spin-glass. Based on structural analysis by Rietveld profile fitting, we suggest that this variation of magnetic property be related to a Jahn-Teller-type attice distortion of MnO6 octahedra due to the introduction of the smaller sized Ca2+ ions. 相似文献
97.
In this paper, new explicit and exact travelling wave solutions for a compound KdV-Burgers equation are obtained by using the hyperbola function method and the Wu elimination method, which include new solitary wave solutions and periodic solutions. Particularly important cases of the equation, such as the compound KdV, mKdV-Burgers and mKdV equations can be solved by this method. The method can also solve other nonlinear partial differential equations. 相似文献
98.
柱前衍生—反相高效液相色谱法测定钢铁及合金中铌 总被引:1,自引:0,他引:1
建立了反相液相色谱法测定钢铁及合金中铌的分析方法。采用HNO3 HF H2 SO4 溶解样品 ,用酒石酸络合铌 ,以 2 (5 溴 2 吡啶偶氮 ) 5 二乙基氨基酚为柱前衍生试剂 ,在C18柱上用甲醇 水 (体积比为 5 6∶4 4 )为流动相 ,其中含 0 .0 1mol·L- 1pH为 3.5的HOAc NaOAc缓冲液。在60 0nm处测定了铌的配合物 ,方法检出限为 1.5 μg·g- 1。应用此法直接测定了合金铸铁和中低合金钢样品中铌 ,其加标回收率为 96.8%~ 10 3.2 % 相似文献
99.
基于铜(Ⅱ)与2-[(5-溴-2-吡啶)偶氮]-5-(二乙胺基)苯酚(5-Br-PADAP)形成稳定络合物的性质,利用717型阴离子交换树脂作为吸附载体,建立了流动注射树脂相吸光光度法测定铜的新方法,并联用单征机实现测定过程的程序化、自动化。此法已成功用于铜尾矿中铜的测定。 相似文献
100.
R. G. Gasanov 《Russian Chemical Bulletin》2000,49(1):46-49
The rate constants for reactions of Cl abstraction from CCl4 by CCl3CH2·CHR radicals and Br abstraction from CCl3CH2CHBrR (R=Bun, AcO, OCNC4H8, CN) by·Re(CO)5 radicals were determined by ESR spectroscopy using spin trapping technique. Replacement of H atoms at the C(β) atom by O
or N atoms reduces the reactivity of the radicals in the reactions of Cl abstraction from CCl4 by approximately an order of magnitude. The presence of two polar groups at the C(β) atom results in appreciable decrease
in the strength of the C−Br bond in CCl3CH2CHBrR adducts.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 45–48, January, 2000. 相似文献