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981.
The decomposition temperatures of the lanthanide organic complexes(η^5-C5H5)2Ln(C6H5CONHO)involving cyclopentadienyl and benzohydroxamic acid ligands were calculated and predicted by the model based on ANNs(artificial neural netowrks)method.The comparison was carried out between results from ANNs method and traditinal regression method.It is proved that ANNs could be used more efficiently for the prediction of decomposition temperature of lanthanide organic complexes. 相似文献
982.
非相干光作用下的Ce:BaTiO3自泵浦相位共轭镜特性 总被引:1,自引:0,他引:1
地Ce:BaTiO3晶体的自泵浦相位共竟然非相干光作用下自泵浦相位共轭反射率增强的特性进行了研究。实验是在He-Ne激光产生稳态自泵浦相位共轭输出后,用非相干光平行c轴照射来获得这一增强特性的,当水平移动非相干光入射位置,发现有两个区域非相干光作用能使相位共轭反射率增加,本文对此进行了相应的分析和讨论。 相似文献
983.
The nature of the temperature dependence of luminescence intensity from Er+ ions in GaInAsP, Si, InP, GaAs, AlGaAs, ZnTe, as observed by Favennecet al [1] has been examined in terms of a double exponential model. The smaller activation energy is found to be 58–100 meV, characteristic
of a localized energy barrier at the Er+ centre while the higher activation energy is approximately 0.8E
g attributed to an Auger non-radiative process of carrier excitation into bands. This model has been found to describe the
observed temperature dependences with reasonably good agreement. 相似文献
984.
Vazid Ali Raminder Kaur Sukhmehar Singh H.P.S. Kang M. Husain 《Journal of Physics and Chemistry of Solids》2006,67(4):659-664
The structural modification and properties of polymeric materials are of utmost importance in deciding their applications. In the present study, the synthesis of polyaniline (PANI) has been carried out via chemical oxidation in acidic medium by potassium-dichromate and the yield of synthesized polyaniline was found to be 75-80%. The copper per chlorate tetrabenzonitrile salt (CuClO4·4BN) used for chemical doping in synthesized polyaniline is stable in organic solvent like acetonitrile (AN) and benzonitrile (BN). The effect of Cu+1 oxidation state (dopant) in polyaniline has been characterized by FTIR. Electrical and dielectric measurements show the decrease in the intensity of the Cu+1 salt signal and the appearance of a radical signal due to the formation of oxidative coupled in polymeric species. Electrical and dielectric properties of doped polyaniline samples show significant changes due to the effect of dopant (CuClO4·4BN). It is observed that the conductivity is contributing both by formation of ionic complex and particularly dominated by electronic due to the mobility of charge carriers along the polyaniline chain. 相似文献
985.
含羧酸共生稀土光敏剂的低密度聚乙烯膜紫外光氧化降解 总被引:3,自引:0,他引:3
含羧酸共生稀土光敏剂的低密度聚乙烯膜紫外光氧化降解林宜超(福建省测试技术研究所福州350003)近年来,许多作者先后研究并开发出含硬脂酸铈(CeSt3)光敏剂的可控光降解低密度聚乙烯(LDPE)[1,2]、高密度聚乙烯[3]、聚丙烯[4]、聚苯乙烯... 相似文献
986.
987.
W. Schott G. Dollinger T. Faestermann J. Friedrich F. J. Hartmann R. Hertenberger N. Kaiser A. R. Müller S. Paul A. Ulrich 《The European Physical Journal A - Hadrons and Nuclei》2006,30(3):603-611
The hyperfine-state population of hydrogen after the bound-β-decay of the neutron directly yields the neutrino left-handedness
or a possible right-handed admixture and possible small scalar and tensor contributions to the weak force. Using the through-going
beam tube of a high-flux reactor, a background free hydrogen rate of ca. 3s^-1 can be obtained. The detection of the neutral
hydrogen atoms and the analysis of the hyperfine states is accomplished by Lamb shift source type quenching and subsequent
ionization. The constraints on the neutrino helicity and the scalar and tensor coupling constants of the weak interaction
can be improved by a factor of ten. 相似文献
988.
对卫星近日点旋进现象的分析——"地球的扁率对卫星运动的影响"一文的疏忽 总被引:1,自引:1,他引:0
指出了一篇相关文献中的疏漏,讨论了卫星近日点的旋进现象,得出了在一般情况下卫星近日点旋进的快慢程度与近日点本身所处的位置有关的结论. 相似文献
989.
XU Xing-Ling TANG Zong-Xun GUO Zhi-Zheng CHEN Yun-ShengDepartment of Chemistry Northwest University Xi''''an Shanxi ChinaSHI Ni-Cheng MA Zhe-Sheng China University of Geoscience Beijin ChinaHAN Yu-Zhen Department of Chemistry Beijin University Beijin China 《中国化学》1995,(1)
Based on the phase equilibrium study of the system Sm(ClO4)3-4-monochloroace-tylantipyrine (C13H13ClN2O2)-H2O at 30℃, we have synthesized the title complex [Sm(C13H13Cl. N2O2)3(H2O)4](C1O4)3.4H2O. The single crystal structure analysis on RASA-IIS Rigaku diffrac-tometer shows that the coordination number of the metal ion is nine and the geometry of the complex is tricapped trigonal prism. Two of the three molecules of organic ligand act as bidentate chelated through both carbonyl oxygens to the metal ion, but the other one as a monodentate coordinated only through the ring carbonyl oxygen, the side chain carbonyl is far away from the central ion. The crystal is monoclinic, space group P21, a = 18.013(4), 6 = 14.709(3), c = 10.536(3) A, β=94.69(2)°, V=2782(1) A3, Z=2. 相似文献
990.
Diamine的光、电性质及其在有机薄膜电致发光器件中的应用 总被引:5,自引:1,他引:4
合成了芳香族二胺类衍生物(diamine),测定了它的光、电性质.制备了diamine作为空穴传输层的二层结构有机薄膜电致发光器件,使器件的发光亮度相对单层器件有了很大的提高.并用不同区域掺杂的方法,探讨了电致发光机理.分析、讨论了激子的形成和复合区域,较好地解释了单、双层器件的不同的电流电压关系和不同的亮度电压关系.从激子的扩散方程出发,对双层掺杂器件的发光强度比数据进行了拟合,确证了激子的扩散模式. 相似文献