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81.
Guijarro A Castillo O Calzolari A Sanz Miguel PJ Gómez-García CJ di Felice R Zamora F 《Inorganic chemistry》2008,47(21):9736-9738
Three new compounds of formula [Pt2(SSCR)4] (R = CH3, (CH2)4CH3, cyclohexyl) have been prepared and characterized by X-ray diffraction. Their crystal structures consist of one-dimensional linear chains formed by stacking of the dimetallic complexes in which the alkyl group on the dithioacetate modulates the intermetallic distances between dimetallic entities. Direct current electrical conductivity studies show that crystals of the three compounds behave as semiconductors and their conductivity values are directly connected to the intermolecular metal-to-metal distances. These experimental results are supported by density functional theory calculations. 相似文献
82.
单重态氧化学VIII.类卟啉稀土配合物光敏化产生单重态氧的ESR研究 总被引:1,自引:0,他引:1
用电子自旋共振(ESR)方法研究类卟啉稀土配合物([CO2H-APPC)Gd]Cl2)光敏产生单重态氧的II型机制。利用2,2, 6, 6-四甲基哌啶(TEMP)对单重态氧的捕捉, 测定所生成的氮氧自由基的ESR信号, 经加NaN3和CD3OD的实验, 证实了([CO2H-APPC)Gd]Cl2)光敏作用可有效地产生单重态氧, 并观察到在实验所用的浓度范围内, 随着光敏剂浓度加大, 生成的单重态氧也增加, 同时比较了几种不同稀土离子配合物产生单重态氧的差别。结合氧的消耗和氮氧自由基的ESR线宽变化对氧浓度的依赖性, 证明了类卟啉稀土配合物光敏化生成单态氧的II型反应在光动力光疗中起关键作用。 相似文献
83.
A Branch and Contract Algorithm for Problems with Concave Univariate, Bilinear and Linear Fractional Terms 总被引:1,自引:0,他引:1
A new deterministic branch and bound algorithm is presented in this paper for the global optimization of continuous problems that involve concave univariate, bilinear and linear fractional terms. The proposed algorithm, the branch and contract algorithm, relies on the use of a bounds-contraction subproblem that aims at reducing the size of the search region by eliminating portions of the domain in which the objective function takes only values above a known upper bound. The solution of contraction subproblems at selected branch and bound nodes is performed within a finite contraction operation that helps reducing the total number of nodes in the branch and bound solution tree. The use of the proposed algorithm is illustrated with several numerical examples. 相似文献
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85.
乐碧宏 《宁波大学学报(理工版)》2005,18(1):122-125
证券风险的计量准确与否,是证券组合理论能否有效运用的前提,在现有研究成果的基础上,结合我国证券市场的特点,选取“流通市值”作为影响我国证券风险的第二个因素,建立了证券风险计量模型,并使用统计软件对模型的适用性进行了检验. 相似文献
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Flix Zamora Pilar Amo-Ochoa Birgit Fischer Arnd Schimanski Bernhard Lippert 《Angewandte Chemie (International ed. in English)》1999,38(15):2274-2275
Not only UV radiation can bring about the dimerization of the pyrimidine nucleobase uracil, a metal ion can as well! The reaction proceeds by a reductive elimination process of two cis-oriented uracil entities, each bonded to AuIII through C5 [Eq. (a)]. R/R′=H/CH3, CH3/CH3, H,C5H9O4 相似文献
89.
α decay half-lives of some new synthesized superheavy elements, possibly synthesized superheavy elements and decay products are calculated theoretically within the WKB approximation by using microscopic α-nucleus interaction potentials. These nuclear potentials between the α particle and daughter nuclei are obtained by using the double folding integral of the matter density distribution of the α particle and daughter nuclei with a density-dependent effective nucleon-nucleon interaction, in which the zero-range exchange term is supplemented. The calculated α decay half-lives are compared with those of the different models and experimental data. It is shown that the present calculation successfully provides the half-lives of the observed decays for some new superheavy elements and therefore gives reliable predictions for α decay of possibly synthesized superheavy elements in future experiments. 相似文献
90.