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高精度CCD尺寸自动检测系统的光学系统设计   总被引:2,自引:2,他引:0  
介绍测量精度为±0.003mm的CCD尺寸检测系统的光学系统设计特点及远心物镜设计原理,并给出了测试结果。  相似文献   
2.
利用1,4-二-(4-羧基吡啶基)丁烷(L)合成了两个新的三维配位聚合物{(CdL2)·4H2O·2ClO4}n 1和{(ZnL2)·4H2O·2ClO4}n 2。单晶X-射线结构分析表明,12具有相同的计量式,但其晶体属于不同的空间群(1属于P4n2,2属于P4222)。两种配合物中,每个金属离子分别由配体与四个相邻的金属离子连接,从而形成具有六重穿插的金刚石网络结构,其网络中大的空腔被高氯酸根离子和(H2O)4分子簇所占据。  相似文献   
3.
In this paper, a scheme of spatial perturbation is introduced into a class of excitable media, which are described by two-dimensional partial-differential equation models. Inertial acentric force (or centripetal force), which is generated by circumgyrating the whole system vs. a right axis, is used to disturb the system. The whole system becomes homogeneous as soon as the spatial perturbation is imposed on even when the noise is in consideration. The principle of this scheme is confirmed based on the theory of Hopf bifurcation and numerical simulation.  相似文献   
4.
Cesium gallium hydrogen triphosphate CsGaHP3O10-III crystallizes in the space group Pca21, a = 1 176.3(1) pm, b = 496.55(5) pm, c = 1 572.2(1) pm and Z = 4. The structure was solved by using 1 268 unique reflections Io > 2σ(Io) with a final wR2 value of 0.0742 (SHELXL-93). The P3O10 chain anions, bonded by Ga, are spreaded in layers parallel (0 0 1); the layers are interconnected by Cspolyhedra and obviously by hydrogen bonds. The interlayer distance is c/2. The new structure is compared with the previously known structures of CsGaHP3O10-I and Cs3Ga3P12O36. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), and the Charge Distribution (CHARDI) are calculated for the title compound.  相似文献   
5.
基于范德瓦耳斯流体的分子聚集模型,应用统计热力学方法导出分子聚集型状态方程。然后,应用两个特性因子一偏心因子(ω)和构形因子(ζ)预测在对比温度Tr=0.7下的化合物的聚集参数(3C*)0。该预测数据表明,(3C*)0。能反映物质的决定分子的聚集行为的结构特性。总的来说,这些数据对我们在基础理论研究方面是有很大意义的。  相似文献   
6.
曾卉一  郭胜平  郑发鲲  郭国聪 《结构化学》2009,28(10):1205-1209
As part of our systematic research on the acentric rare earth chalcogenides, the ErAlGeS5/KBr, Er3AgGeS7/KBr and Er6Ge3S14/KBr systems were investigated and three compounds belonging to the R6B2C2Q14 (R = rare earth, B = 6-coordinated element, C = 4-coordinated element, Q = S and Se) family were identified. These compounds crystallize in the P63 space group, and the crystal data are as follows: Er3Ge1/4GeS7, a = 9.6480(14), c = 5.7920(12) A^°, Z = 2; Er3Ge0.382(8)GeS7, a = 9.6360(14), c = 5.8460(12) A^°, Z = 2; Er3Ge1/2GeS7, a = 9.6061(13), c = 5.8346(18)A^°, Z = 2. Single-crystal analysis indicated that the Er3GexGeS7 (x = 1/4, 0.382(8), 1/2) structures consist of three types of building blocks: ErS7, GeS4 and GeS6 units. Er3MxGeS7 are deficient compounds with the B sites occupied partly by Ge(Ⅳ) and/or Ge(Ⅱ).  相似文献   
7.
Single crystals of caesium iron hydrogen phosphate, Cs3Fe3H15(PO4)9, 2 , were prepared hydrothermally by heating caesium iron dihydrogenphosphate, CsFe(H2PO4)4, 1 , with a small amount of water. 2 crystallizes orthorhombic, space group Pna21 (No. 33 Int. Tab.) with Z = 4 and a = 2718(1), b = 908.1(3), c = 1280.8(4) pm. The crystal structure was solved by using 4734 unique reflections I > 2σ(I) with a final wR2 value of 0.0801 (SHELXL-93). The main feature of the crystal structure are channels formed by combined PO4-tetrahedra and FeO6-octahedra along the [001] direction. Cs+ is placed inside of the channels. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), Charge Distribution (CHARDI) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound.  相似文献   
8.
Wiener指数与饱和烷烃偏心因子的关系研究任碧野(岳阳大学化工系岳阳414000)关键词Wiener指数,偏心因子,定量结构-性质相关性近年来,利用拓扑指数作为表征分子结构特征的数学量来进行物质定量结构一性质相关性(QSPR)研究非常活跃。其中应用...  相似文献   
9.
Molecular crystals exhibiting polar symmetry are important paradigms for developing new electrooptical materials. Though accessing bulk polarity still presents a significant challenge, in some cases it may be rationalized as being associated with the specific molecular shapes and symmetries and subtle features of supramolecular interactions. In the crystal structure of 3,5,7‐trinitro‐1‐azaadamantane, C9H12N4O6, the polar symmetry of the molecular arrangement is a result of complementary prerequisites, namely the C3v symmetry of the molecules is suited to the generation of polar stacks and the inherent asymmetry of the principal supramolecular bonding, as is provided by NO2(lone pair)…NO2(π‐hole) interactions. These bonds arrange the molecules into a trigonal network. In spite of the apparent simplicity, the structure comprises three unique molecules (Z′ =  +  + ), two of which are donors and acceptors of three N…O interactions and the third being primarily important for weak C—H…O hydrogen bonding. These distinct structural roles agree with the results of Hirshfeld surface analysis. A set of weak C—H…O and C—H…N hydrogen bonds yields three kinds of stacks. The orientation of the stacks is identical and therefore the polarity of each molecule contributes additively to the net dipole moment of the crystal. This suggests a special potential of asymmetric NO2(lone pair)…NO2(π‐hole) interactions for the supramolecular synthesis of acentric materials.  相似文献   
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