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61.
高光通量短波红外静止干涉成像光谱仪研究 总被引:2,自引:1,他引:1
讨论高光通量静止干涉(傅里叶变换)成像光谱仪的基本原理及结构特点,建立了短波红外的高光通量静止傅里叶变换光谱仪的实验系统,给出了实验结果。 相似文献
62.
本文应用多重尺度法构造出非线性微分方程组的解的渐近展开式。并用微分不等式的技巧,证明原问题的解的存在性,且给出解的一致有效渐近估计. 相似文献
64.
Two coordination polymers, namely, two-dimensional complex 1 {[Cu(μ- L)1.5(ClO4)2(H2O)].(H2O)0.5}n (L = pyrazine-1,4-dioxide) and one-dimensional complex 2 [Co(μ-L)Br2(H2O)2]n, have been synthesized with pyrazine-1,4-dioxide as bridging ligands, and their crystal structures were determined by X-ray crystallography. Crystal data for complex 1: monoclinic system, space group C2/c, with a = 23.310(3), b = 12.2338(17), c = 10.6075(15) , β = 110.487(2)°, V = 2833.6(7) 3, Z = 8, C6H9Cl2CuN3O12.5, Mr = 457.60, Dc = 2.145 g/cm3, F(000) = 1832 and μ = 1.998 mm-1; and those for 2: monoclinic system, space group C2/c, with a = 11.012(3), b = 7.483(2), c = 11.451(3) , β = 101.654(4)°, V = 924.2(4) 3, Z = 4, C4H8Br2CoN2O4, Mr = 366.87, Dc = 2.637 g/cm3, F(000) = 700 and μ = 10.487 mm-1. 1 shows a two-dimensional sheet structure on the ac plane through the coordination of μ-L bridging ligands with Cu(II) ions, while 2 displays a zigzag one-dimensional chain along the c axis via the coordination of μ-L bridging ligand with Co(II) ions. Hydrogen bonds in 1 and 2 make the sheets (or chains) connect each other to form a three-dimensional structure. 相似文献
65.
The runoff of the Huanghe contains a great amount of suspended load and forms the high-density underflows (hyperpycnal currents) at the river mouth. The sediments over the subaqneous delta are mainly transported by the underflow. The sediment texture gradually get fining seawards, which relates to the attenuation of the hyperpycnal currents and hypopycnal plumes. Being hydraulically equivalent to the medlum-silt-sized quartz, which is the dominant component in the sediments, the clastic mica concentrates on the delta. The maximum thickness of the subaqueous delta is about 16m and the period of accumulation lasted from 12 to 16 years, therefore its sedimentary rate ranges from 110 to 130 cm/a. 相似文献
66.
Cl···O intramolecular contacts are analysed here. Hence the Cambridge Structural Database (CSD) search was performed to find
five-membered Cl–C=C–C=O pseudo-rings closed through Cl···O intramolecular contacts. Such rings were analysed and it was found
that some of Cl···O distances are smaller than the corresponding sum of van der Waals radii. Additionally ab initio MP2/6-311++G(d,p)
calculations and AIM analyses were carried out here on 3-chloropropenal and its fluoro derivatives to deepen the nature of
intramolecular Cl···O interactions, some of findings may indicate that they are attractive and stabilizing ones.
This paper is dedicated to Prof. T. M. Krygowski on the occasion of his 70th birthday 相似文献
67.
首次采用Materialsstudio软件中不同的交换-相关势能函数对N-(1-萘基)-琥珀酰亚胺进行密度泛函理论计算,通过与文献报道的B3LYP/6-311G**常规计算方法进行比较,以及MP2/6-311G**方法进行单点能计算,确认所采用方法计算N-(1-萘基)-琥珀酰亚胺分子最低能量构象更接近整个势能面的全局最小点;振动频率理论分析结果与N-(1-萘基)-琥珀酰亚胺化合物羰基振动双重分裂的红外光谱特征相吻合,表明红外光谱可以作为琥珀酰亚胺类化合物的重要表征方法;根据对N-(1-萘基)-琥珀酰亚胺、萘和萘胺的轨道分布和电荷密度进行理论分析,解释了N-(1-萘基)-琥珀酰亚胺化合物溶液的紫外和荧光的光谱特征,并进而可推断N-(1-萘基)-琥珀酰亚胺分子在溶液中的构象和理论计算得到的真空中最低能量构象相同,其二面角为94.995°。 相似文献
68.
过渡金属酞等配合物(MPC)用手均相液相氧化中作催化剂已有不少报导,象许多均相催化剂一样,MPC用于均相反应存在着难于从反应体系中分离出来的问题.把均相配合物催化剂固载在无机氧化物如硅股或有机高分子载体上是解决这一问题的一种方法.我们曾尝试把MP。固载在分子筛载体和硅胶载体上,并用ESR研究其对O2的活化作用[1,2].本文报导MPc通过共价键键联固载在SiO2上,并研究其对O2的活化作用.1实验部分1.1试剂HSIC13为日本东京化成株式会社产品,二级试剂·发烟硫酸(SO。质量分数大于20%)为分析纯试剂.PCl5为化学纯试… 相似文献
69.
Summary In this paper an application is presented of the median molecule workflow to the de novo design of novel molecular entities with a property profile of interest. Median molecules are structures that are optimised to be similar to a set of existing molecules of interest as an approach for lead exploration and hopping. An overview of this workflow is provided together with an example of an instance using the similarity to camphor and menthol as objectives. The methodology of the experiments is defined and the workflow is applied to designing novel molecules for two physical property datasets: mean molecular polarisability and aqueous solubility. This paper concludes with a discussion of the characteristics of this method. 相似文献
70.