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11.
The title polymeric complex of Cu(II) and Cd(II) bridged by thiocyanate, Cu(en)2[Cd(SCN)3]2, has been prepared and its structure determined by X-ray diffraction (XRD) methods. The crystal structure reveals that the Cu(II) atom is in an elongated octahedral coordination formed by two SCN– anions and two en molecules. The Cd(II) atom is in a distorted octahedral coordination formed by six bridging SCN– anions. Two different bridging thiocyanate anions exist in the complex. Both 1,1--SCN– and 1,3--SCN– anion act a role of bridge ligand and link Cu(II), Cd(II) atoms, and adjacent Cd(II). Cd(II) atoms form the three-dimensional (3-D) network polymeric structure. The IR and UV-Vis spectra have also been investigated. 相似文献
12.
采用浸渍法将甲草胺吸附到纯硅MCM-41(M41)介孔材料中, 以六甲基二硅氮烷(HMDS)为表面改性剂, 通过气-固反应对吸附了甲草胺的M41材料(Ach/M41)进行疏水改性, 得到了既具有高载药性又能有效延缓甲草胺释放的缓释体系Ach/TMS-M41. XRD、低温N2吸附/脱附、FT-IR和TG等分析结果表明, 甲草胺在M41中的吸附量高达0.381 g·g-1(质量分数为27.6%), 此时M41仍保持原有的孔道结构, 且甲草胺能完全分散于M41孔道中. 分别对Ach/M41和Ach/TMS-M41在水中的缓释性能进行了测试, 甲草胺释放率分别为62%和38.1%, 表明疏水改性对延缓甲草胺释放有较好的效果. 而且, 介孔材料孔壁对甲草胺具有明显的紫外屏蔽保护作用. 相似文献
13.
Miao-Kun Wang Yu-Ming Chu Song-Liang Qiu Yue-Ping Jiang 《Journal of Approximation Theory》2012,164(7):928-937
In this paper, we present several bounds for the perimeter of an ellipse, which improve some well-known results. 相似文献
14.
15.
A field method for integrating the equations of motion of mechanico--electrical coupling dynamical systems 下载免费PDF全文
A field method for integrating the equations of motion for mechanico-electrical coupling dynamical systems is studied. Two examples in mechanico-electrical engineering are given to illustrate this method. 相似文献
16.
Based on the truncated second-order moments method on the cylindrical coordinate systems and the incomplete gamma function, an analytical expression of the generalized beam propagation factor (MG2 factor) of hard-edged circular apertured diffracted Bessel–Gaussian beams is derived and illustrated numerically. It is shown that the MG2 factor of hard-edged diffracted BGBs mainly depends on the truncation parameter δ and the beam parameters m and η. The results can be reduced to that for the non-truncated Bessel–Gaussian beams case and that for the truncated fundamental Gaussian beams case under certain conditions, respectively. The power fraction is also discussed analytically and numerically. 相似文献
17.
《Chaos, solitons, and fractals》2007,31(3):631-638
In this paper, impulsive control and synchronization for the newly presented Lorenz systems family are systematically investigated. Some new and more comprehensive criteria for global exponential stability and asymptotical stability of impulsively controlled Lorenz systems family are established with varying impulsive intervals. In particular, several simple and easily verified criteria are derived with equivalent impulsive intervals. An illustrative example is also provided to show the effectiveness and feasibility of the impulsive control method. 相似文献
18.
Highly efficient and chemoselective N‐heterocyclic carbene palladium complexes‐catalyzed multicomponent carbonyltive Suzuki reaction with sodium tetraphenylborate used as phenylating reagent has been demonstrated in this article. Both electron‐rich and electron‐deficient aryl iodides gave unsymmetric aryl ketones in excellent yields. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
19.
We describe maximal regular subsemibands of the singular transformation
semigroup Singn on the set Xn = {1, 2, . . . n} and obtain their complete classification
We show that Singn has n(n + 1)/2 maximal regular subsemibands,
and formulate the cardinal number of such subsemigroups. 相似文献
20.