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941.
J. C. Lpez V. A. L. Rivera Yu. F. Smirnov A. Frank 《International journal of quantum chemistry》2002,88(2):280-295
The calculation of Franck–Condon factors between different 1‐D Morse potential eigenstates using a formula derived from the Wigner function is discussed. Our numerical calculations using a simple program written in Mathematica are compared with other calculations. We show that our results have a similar accuracy as those calculations performed with more sophisticated methods. We discuss the extension of our method to include non‐Condon effects in the calculation. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem 88: 280–295, 2002 相似文献
942.
In this study, we report the design and synthesis of a series of new simplified fumitremorgin C analogues. The preliminary biological study indicated some of these simplified fumitremorgin C might be developed into breast cancer resistance inhibitors. 相似文献
943.
Li Jiang Fushen Lu Qing Chang Yang Liu Huibiao Liu Yuliang Li Wei Xu Guanglei Cui Junpeng Zhuang Xiaofang Li Shu Wang Yinglin Song Daoben Zhu 《Chemphyschem》2005,6(3):481-486
An ultrathin composite film containing anionic Ag-His complexes (His: L-Histidine) and oppositely charged BH-PPV was fabricated by means of the electrostatic layer-by-layer self-assembly technique. UV/Vis spectra showed a continuous deposition process of Ag-His complexes and BH-PPV. The film structure was characterized by using small-angle X-ray diffraction, AFM, and SEM. The nonlinear optical properties of the ultrathin film were studied by using the Z-scan technique with a laser duration of 8 ns at a wavelength of 532 nm. The film sample exhibited a strong nonlinear saturated absorption, with an alpha2 value of -3.9 x 10(-5) mW(-1) and a self-defocusing effect with an n2 value of -4.78 x 10 (-12) m2W(-1). 相似文献
944.
铜基催化剂的结构、物性及其对混合碳四选择加氢反应的催化性能 总被引:2,自引:0,他引:2
用XRD,XPS,SEM和H2-TPR等手段研究了铜基负载型催化剂的结\r\n构和物性及其对混合碳四加氢脱炔的催化性能.结果表明,在负载铜催\r\n化剂中加入一定量的Co可提高催化剂的加氢脱炔活性,而Co含量较少时\r\n加入少量的Ce也能提高催化剂的活性和选择性.Cu和Co之间存在着相互\r\n协同作用,使得活性组分在催化剂表面偏析,CuO在催化剂表面呈非晶\r\n相分散状态,催化剂颗粒粒径变小,催化剂更容易被还原,从而改善了\r\n催化剂的催化性能. 相似文献
945.
以N2与H2的混合气为反应气,和三氧化钼进行多段程序升温反应,制得一种β晶型的氮化钼。以噻吩为模型化合物的常压加氢脱硫反应表明,β-Mo2N0.78具有较强的加氢脱硫活性和强的抗硫化性能。同时考察了预还原、反应温度以及氮化末温、升温速率、反应气中N2-H2比及氮化时间等制备参数对β-Mo2N0.78加氢脱硫活性的影响。研究发现,β-Mo2N0.78的加氢脱硫活性在320 ℃~400 ℃随反应温度的升高增强,而还原预处理会降低催化剂的活性。氮化末温、氮化时间、反应气组成和升温速率等制备参数对催化剂的活性有明显的影响:随着氮化末温的升高,所制备的催化剂催化加氢脱硫活性降低;在氮化末温恒温较长时间,可以引起制备催化剂的加氢脱硫活性下降;存在最佳的反应气组成和各段升温速率。小晶粒的β-Mo2N0.78具有强的加氢脱硫活性。 相似文献
946.
The room temperature ionic liquid n‐butylpyridinium tetrafluoroborate (BPyBF4) is used as a ‘green’ recyclable alternative to classical molecular solvents for the cyclocondensation of α‐tosyloxyketones with 1‐aminoisoquinoline to prepare imidazo[2,1‐a]isoquinolines in good yields. 相似文献
947.
Facile synthesis of exfoliated and highly conductive poly(arylene disulfide)/graphite nanocomposites
Exfoliated graphite has been synthesized by first synthesizing H2SO4 intercalated compound in a H2O2‐H2SO4 mixture, followed by exfoliation under microwave irradiation. Poly(arylene disulfide)/graphite nanocomposites were then fabricated by absorbing cyclic(arylene disulfide) oligomers into the pores of exfoliated graphite. Subsequently, the nanocomposite precursor was subjected to heat treatment to carry out the in situ ring‐opening polymerization of the oligomers via free radical mechanism. The as‐prepared nanocomposite exhibited a exfoliated nanostructure as evidenced by transmission electron microscopy (TEM) observation. The nanocomposite with a very small amount of graphite, 5 wt%, possesses a highly electrical conductivity of 4 S/cm, therefore, many applications can be found as conductive materials. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
948.
A series of pyrazolo[3,4‐b]pyridines was synthesized by the reaction of 5‐aminopyrazole with benzylidenemalononitrile in aqueous media. The structures were characterized by IR, 1H NMR, and elemental analysis and were further confirmed by X‐ray diffraction analysis. 相似文献
949.
Paul V. Bernhardt Dr. Geoffrey A. Lawrance Brian W. Skelton Allan H. White 《无机化学与普通化学杂志》2007,633(7):1036-1039
Cations derived by protonation of the ligand title compound (L1) have been structurally characterized in their di‐ and tetra‐ protonated forms in the salts [H2L1][ClO4]2·2H2O and [H4L1][ZnCl4]2·4H2O. In both structures, one half of the formula unit comprises the asymmetric unit of the structure, the macrocycle being centrosymmetric, with the two macrocycles adopting similar conformations. In both salts, a pair of diagonally opposed macrocyclic secondary amine groups are protonated; in the [H4L1]4+ salt, the additional pair of protons are accommodated on the exocyclic pendant amine groups. The dispositions of the pendent amines differ between the two structures, being ‘equatorial’ with respect to the macrocyclic ring in the [H2L1]2+ salt, and ‘axial’ in the [H4L1]4+ salt. In other structurally characterized compounds containing [H4L1]4+ the equatorial disposition was found in the ferricyanide adduct, while in the tetraperchlorate salt the axial disposition was identified. The differences in disposition of the exocyclic groups are ascribed to the extensive H‐bonding in the lattices. 相似文献
950.