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C60与有机胺电荷转移配合物的吸光特性比较研究 总被引:3,自引:0,他引:3
考察了甲苯、CCl4和环己烷三种溶剂体系中,C60同N,N二甲基苯胺(DNA)、二乙胺(DEA)及三乙胺(TEA)电荷转移配合物(CTC)的吸光特性。发现不同胺同C60作用的程度在不同溶剂介质中均存在如下顺序:环己烷〉CCl4〉甲苯。而在同一溶剂介质中,不同胺同C60作用的程度各不相同。测定了电转移配合物在不同溶剂介质中的摩尔吸光系数及形成常数,并考察了温度对电荷转移配合物形成常数的影响。 相似文献
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碳的一种新形态—C60 总被引:2,自引:1,他引:1
文论述了C60的发现及其研究的最新进展,内容包括:历史上C60研究中的几个重要的事件,C60的合成及纯化方法,C60的几何结构、振动光谱、电子光谱、电子能级,C60的超导、磁化率等电磁性质,以及C60的衍生物化学等;还讨论了C60作为近几年化学中一项重要的发现给化学和物理工作者带来的机会和C60在前沿研究中的重要意义. 相似文献
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C60的发现,制备,结构,性质及其潜在应用前景 总被引:4,自引:0,他引:4
C60是碳的一种新的同素异型结构.本文综述了C60的发现与制备方法,C60形成的机制与其绪构特征,以及C60的性质与其潜在的广阔应用前景.重点介绍用红外(IR)谱,13C核磁共振(NMR)谱和X射线衍射(XD)谱研究C60结构的结果,及掺杂C60固体的高温超导电性及其结构的最新研究进展. 相似文献
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本利用分子间的相互作用模型,研究了固体C60势能面的特性,分析了固体C60的取向无序和有序,以及取向相变的物理原因。 相似文献
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石墨电弧放电过程中C60/C70的形成与氧化 总被引:1,自引:1,他引:0
本文用红外吸收光谱法研究发现,在用石墨电弧放电法制备C60/C70的过程中,有大量的C60/C70氧化物生成。该氧化物具有半导体特性和真空中热稳定性好的优点。 相似文献
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研究了C60和C70分别在溶液,聚苯乙烯薄膜两种不同状态下的吸收特性,实验结果表明,C60在聚苯乙烯薄膜中的吸收峰相对于在正己烷中峰位红移2~10nm,并且发现随着C60浓度的增大,薄膜中观察到有形状规则的针状固体物质出现,C70在聚苯乙烯薄膜中吸收峰同在甲苯中峰位基本重合,我们认为:C60在聚苯乙烯薄膜中是以“微晶”形式存在,而C70在聚苯乙烯薄膜中以比C60更小的颗粒存在或以单分子形式存在。同 相似文献
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Setzer KD Fink EH Alekseyev AB Liebermann HP Buenker RJ 《Journal of Molecular Spectroscopy》2001,206(2):181-197
Gas-phase emission spectra of the hitherto unknown free radical TeLi have been measured in the NIR range with a Fourier-transform spectrometer. The emissions were observed from a fast flow system in which tellurium vapor in argon carrier gas was passed through a microwave discharge and mixed with lithium vapor in an observation tube. Two systems of blue-degraded bands were measured at high spectral resolution in the ranges 8000-9000 and 5700-6700 cm(-1) and vibrational and rotational analyses were performed. In order to aid in the analysis of the experimental data, a series of relativistic configuration interaction calculations has been carried out to obtain potential curves for the low-lying states of TeLi and the isovalent TeH and also electric dipole transition moments connecting them. As in the TeH system, the ground state of TeLi is found to be X(2)Pi(i), but with a remarkably smaller spin-orbit splitting. The TeLi calculations indicate a strongly bound A(2)Sigma(+) state, while in TeH the analogous state is computed to lie significantly higher at approximately 32 000 cm(-1), and it is strongly predissociated. Based on the theoretical analysis, the observed TeLi band systems are assigned to the transitions A(2)Sigma(+)(A1/2)-->X(1)(2)Pi(3/2)(X(1)3/2) and A(2)Sigma(+)(A1/2)-->X(2)(2)Pi(1/2)(X(2)1/2). Analysis of the spectra has yielded the molecular constants (in cm(-1)) X(1)(2)Pi(3/2):omega(e)=457.49(3), omega(e)x(e)=2.482(9), B(0)=0.408908(8); X(2)(2)Pi(1/2): T(e)=2353.44(3), omega(e)=456.28(4), omega(e)x(e)=2.635(8), B(0)=0.414954(8), p(0)=1.00637(4); A(2)Sigma(+): T(e)=8574.64(2), omega(e)=437.81(3), omega(e)x(e)=2.581(8), B(0)=0.423903(8), p(0)=-0.19915(2), where the numbers in parentheses are the standard deviations of the parameters. Comparison of the isovalent TeLi and TeH systems emphasizes that the difference in bonding character (ionic in TeLi vs covalent in TeH) is responsible for qualitative differences in the electronic spectra of these two molecules. Copyright 2001 Academic Press. 相似文献
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The classical optimization problems of plates and shells to satisfy a priori given geometry and dynamical characteristics are considered. Orthotropic plates and shells with variable thickness and low transverse stiffness are analyzed. First, some useful theorems and their proofs are given. Then the finite approximation of the problem related to optimization of free vibrations of shells with transverse deformation and rotary inertia is discussed. The varational iteration (MVI) and Bubnov-Galerkin (MB) methods are applied, and their convergence and suitability for application to plates and shells analysis are discussed and numerically evaluated. 相似文献
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反应堆堆芯的燃耗计算关系到堆芯的燃料管理,并直接影响堆芯的经济性评估,因此如何快速且准确地对堆芯进行燃耗计算一直是反应堆物理设计的研究重点之一。随着反应堆的发展,其几何结构和物理特性日渐复杂,现有的一维、二维耦合燃耗程序因其在几何处理上的限制,难以满足先进反应堆精细设计分析的要求。为对复杂反应堆堆芯的燃耗情况进行计算,结合粒子输运程序MCNP 处理复杂几何和燃耗程序FISPACT处理核素全面的特点,开发了接口程序耦合MCNP 和FISPACT来进行燃耗计算,并对耦合程序进行了计算验证。采用了IAEA 基准校核例题和CFETR中国聚变工程实验堆例题进行程序验证,经计算得出的有效倍增因子随燃耗的变化曲线和TBR等数据与标准例题的结果符合良好,其误差在可接受范围内。 相似文献
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Gregory A. Chung Benjamin Akih-Kumgeh Graeme M.G. Watson Jeffrey M. Bergthorson 《Proceedings of the Combustion Institute》2013,34(1):831-838
NO formation and flame propagation are studied in premixed flames of iso- and n-isomers of butane and butanol through experimental measurements and direct simulation of experimental profiles. The stabilized flame is realized through the impingement of a premixed combustible jet from a contraction nozzle against a temperature-controlled plate. The velocity field is obtained by means of Particle Image Velocimetry (PIV) and nitric oxide concentration profiles are measured using Planar Laser Induced Fluorescence (PLIF), calibrated using known NO seeding levels. It is found that NO formation in n- and iso-isomers is comparable under the conditions considered, except for rich butanol mixtures, whereby NO formation is higher for iso-butanol. Generally, less NO is formed in butanol flames than in the butane flames. The experiment is simulated by a 1D chemically reacting stagnation flow model, using literature models of C1–C4 hydrocarbons [Wang et al., 2010] and butanol combustion chemistry [Sarathy et al., 2009, 2012]. NO prediction is tested using two of these mechanisms with a previously-published NOx submechanism added into the butane and butanol models. While a good level of agreement is observed in the velocity field prediction under lean and stoichiometric conditions, discrepancies exist under rich conditions. Greater discrepancies are observed in NO prediction, except for the C1–C4 mechanism which shows good agreement with the experiment under lean and stoichiometric conditions. The current study provides data for further development of mechanisms with NOx prediction capabilities for the fuels considered here. 相似文献
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V. Ya. Prinz 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2008,2(1):12-19
An original technology and the properties of new thin film nanoobjects, free films and shells of molecular and atomic thicknesses, are presented. Special attention is paid to shells of monoatomic or monomoleculer thickness with unique surface properties that have not been found in bulk materials. 相似文献
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We solve several problems that involve imposing metrics on surfaces. The problem of a strip with a linear metric gradient
is formulated in terms of a Lagrangian similar to those used for spin systems. We are able to show that the low energy state
of long strips is a twisted helical state like a telephone cord. We then extend the techniques used in this solution to two–dimensional
sheets with more general metrics. We find evolution equations and show that when they are not singular, a surface is determined
by knowledge of its metric, and the shape of the surface along one line. Finally, we provide numerical evidence by minimizing
a suitable energy functional that once these evolution equations become singular, either the surface is not differentiable,
or else the metric deviates from the target metric. 相似文献
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Ming Yang Xiao Yang Lufeng Huai 《Applied Physics A: Materials Science & Processing》2008,92(2):367-370
Hollow spheres and nanospheres of Au have been prepared by a simple reaction of HAuCl4·4H2O, NaOH and (NH2OH)2·H2SO4 in the presence of gelatin. The role of gelatin and the effect of the temperature of the reaction in producing the spherical
particles of Au are discussed. The products were characterized by powder X-ray diffraction (XRD), transmission electron microscopy
and UV–Vis absorption spectroscopy. The sizes of the nanospheres of Au were estimated by the Debye–Scherrer formula according
to the XRD spectrum.
PACS 81.05.Bx; 81.05.Rm; 81.07.-b; 81.16.Be; 81.20.Fw 相似文献