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41.
研究了(Ti,Al)薄膜的光学特性,对其反射和透射光谱作了仔细分析。运用Hadley方程,算出一定成分(Ti,Al)N膜的折射率n,消光系数k随波长的变化关系。又根据透射曲线,计算出了(Ti,Al)N膜的光隙能。 相似文献
42.
Deformed Hartree-Fock calculations are performed for some light nuclei in a large configuration space consisting of first
four major shells. The interaction employed is the modified Skyrme interaction in which the deformed density is replaced by
the band averaged scalar density that makes the Hamiltonian rotationally invariant rendering the spectroscopic calculations
feasible. It is shown that the introduction of density dependence spreads out the energy spectra and that the Skyrme variant
SIV which has a weak density dependence gives best overall agreement for energy spectra and the available data for the electromagnetic
properties of the nuclei studied. It is found that the maximum contribution to the energy of any state in the low lying spectrum
comes from thes-state attractive ands-state repulsive parts of the Skyrme interaction. It is also shown that when two-body density dependent version of Skyrme
interaction is used, the Koopmans theorem no longer holds. 相似文献
43.
《Journal of Coordination Chemistry》2012,65(2):231-239
Abstract The FT-Raman and FT-IR spectra of crystalline glutarimide and its N-deuterated derivative have been recorded in the range 4000-100 cm?1. A complete vibrational assignment is given for all internal modes and is supported by normal coordinate analysis based on a general valence force field. The calculated frequencies are in very good agreement with experiment. A close similarity is found for frequencies of the corresponding vibrations of glutarimide and uracils in the solid state. It is concluded that the strength of hydrogen bonding in glutarimide is very similar to that in crystalline pyrimidine nucleic bases. 相似文献
44.
E. Grell E. Lewitzki C. Bremer S. Kramer-Schmitt J. Weber A. E. Senior 《Journal of fluorescence》1994,4(3):247-250
lin-Benzo-adenine nucleotides can act not only as probes for fluorescence studies but also as structural active site probes for enzymes. To understand the basic properties oflin-benzo-ATP and-ADP, protolysis and Mg2+ and Ca2+, binding are investigated between pH 6.2 and pH 8.5 by spectrophotometric and spectrofluorometric titrations. Based on a reaction model, a set of equilibrium constants is determined which is consistent with all available experimental results. The pK values of the Mg2+ and Ca2+ complex oflin-benzo-ATP in the chosen medium are 4.6 and 4.1, respectively, and those for the corresponding diphosphate are 3.1 and 2.8, respectively. Fluorescence and absorption spectra are reported.This is a peer-reviewed conference proceeding article from the Third Conference on Methods and Applications of Fluorescence Spectroscopy, Prague, Czech Republic, October 18–21, 1993. 相似文献
45.
The transmitted photon spectra of133Ba,22Na,137Cs,54Mn and60Co point sources are measured through different thicknesses of water, concrete and sand. The multiple-scatter peaks observed
in these materials at 60, 90 and 100 keV energies respectively are found to be independent of incident photon energy and thickness
of the medium. 相似文献
46.
Alain Joye 《Journal of statistical physics》1994,75(5-6):929-952
The spectrum of the Floquet operator associated with time-periodic perturbations of discrete Hamiltonians is considered. If the gap between successive eigenvalues
j
of the unperturbed Hamiltonian grows as
j
-
j-1
j
and the multiplicity of
j
grows asj
with >0 asj tends to infinity, then the corresponding Floquet operator possesses no absolutely continuous spectrum provided the perturbation is smooth enough. 相似文献
47.
本文报道室温下Cd3Al2Ge3O12:Mn2+(简称CAGG:Mn2+)锗酸盐石榴石的漫反射光谱、激发和发射光谱.在UV光激发下,在CAGG中Mn2+离子发射强黄光,这是基质到Mn2+离子无辐射能量传递的结果.Mn2+的黄发射带是由一个弱的红带和一个强的绿带所组成.讨论了这两个Mn2+发射带的起因. 相似文献
48.
Eu3+、Tb3+与1-乙酰乙酰吲哚、1,10-邻菲啰啉二元、三元体系在溶液中荧光光谱研究 总被引:2,自引:0,他引:2
观察了以不同比例溶解在乙醇中的Eu3+、Tb3+、1-乙酰乙酰吲哚(HL)和1,10-邻菲啉(Phen)的荧光光谱.结果表明HL能有效地把吸收的能量传递给Tb3+,而不能有效地传递给Eu3+.讨论了HL和Phen对Eu3+、Tb3+的配位作用及其对Eu3+或Tb3+所组成的三元体系中敏化发光性能的影响. 相似文献
49.
Tsutomu Sato 《Pramana》1983,21(6):375-384
The first-order Raman spectra ofE
gandA
1g
modes in MnF2 crystal were measured at temperatures from 4.2 to 563 K, and the values of the linewidths obtained. The temperature dependence
of the linewidths was analyzed by the phonon dispersion curves based on the rigid ion model, and the result showed that it
was caused approximately by the cubic anharmonic term in crystal potential energy. 相似文献
50.
陈玉锋 《原子与分子物理学报》2021,38(2):021003-021003-5
马来酸氯苯那敏(chlorpheniramine maleate,CPM),化学名为2-[对-氯-α-(二甲氨基)乙基丁苯基], 又名扑尔敏,分子式C20H23ClN2O4,本文采用密度泛函理论(density functional theory,DFT),在M06-2X/6-311+g(d,p)水平上对扑尔敏分子的两种可能的结构进行了优化,优化结果显示分子基态结构具有C1对称性,分子由50个原子组成,共有144个简正自由度,所有的简正振动模式均具有拉曼活性。计算结果表明,吡啶环和苯环所在平面的二面角是92.1°,丁烯二酸和苯环所在平面的二面角是-174.5°。O40-H41和H41-N25键长分别为0.103nm、0.162nm,O40-H41-N25键角为175.29°,采用多功能波函数Multiwfn软件处理结果表明用于表征氢键强度的CVB指数(CVB指数越负,通常氢键越强。)为-0.2268,结果表明O40-H41-N25原子之间存在氢键,马来酸通过羧基上的氢原子和氯苯那敏吡啶环上的N原子通过氢键作用相结合;通过频率计算,获得了扑尔敏分子的拉曼光谱,并利用势能函数分布(PED)对拉曼光谱进行了指认,对谱图信息比较丰富的200-1800cm-1波段进行了分析归属;此外分析并讨论了扑尔敏分子的前线轨道,扑尔敏分子的最高占据轨道HOMO和最低未占据分子轨道LUMO轨道能量分别为-7.95ev、-1.05ev,能级差为6.90ev。为扑尔敏分子的光谱测定和电子结构分析提供了理论基础。 相似文献