Structure and Luminescent Properties of the First Cadmium Complex with Isophthalate and Di-pyrazole Ligands

The title complex [Cd(IPA)L(H2O)]n(1,H2IPA = isophthalic acid,L = 1,4-bis(pyra-zole-1-ylmethyl)benzene) has been hydrothermally synthesized,and characterized by elemental analyses,IR spectroscopy,TGA and X-ray single-crystal diffraction.It crystallizes in the triclinic system,space group P1 with a = 9.3060(6),b = 10.2374(7),c = 11.9706(8) ,α = 73.804(6),β = 77.883(5),γ = 85.942(5)°,V = 1070.7(1) 3,Z = 2,C22H20CdN4O5,Mr = 532.82,Dc = 1.653 g/cm3,μ = 1.062 mm-1,λ(MoKα) = 0.71073 ,F(000) = 536,R = 0.0392 and wR = 0.0640 for 3751 observed reflections with I > 2σ(I).Crystal structure analysis showed that complex 1 has a 1D double chain structure,which is assembled together through strong O-H...O hydrogen bonding interactions between coordinated water molecules and carboxylate groups of isophthalate to form a 2D supramolecular network.In addition,the solid-state fluorescent spectrum of 1 exhibits strong emission at 364 nm.     

Synthesis and Characterization of a Two-dimensional Cadmium(Ⅱ) Metal Organic Framework with Fes Topology

A new Cd(Ⅱ) coordination polymer, {[Cd(Hnbta)(L)]·H2O}n(L = 1,4-bis(5,6-dimethylbenzimidazol-1-yl)butane), H3nbta= 5-nitrobenzene-1,2,3-tricarboxylic acid), has been hydro-thermally synthesized and characterized by elemental analyses, IR, XRPD, and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P21/n with a = 17.3056(13), b = 11.0114(9), c = 17.7484(14) A, β = 117.3640(10)o, V = 3003.7(4) A3, Z = 4, C31H31CdN5O9, Mr = 730.01, Dc = 1.614 g/cm3, μ = 0.792 mm-1 and F(000) = 1488. The cadmium(Ⅱ) ions are bridged by Hnbta2- to generate a two-dimensional metal organic framework with fes topology. In addition, the thermal stability and fluorescence properties of the complex were also studied.     

A Dinuclear Cu(Ⅱ)-based Coordination Framework with Two-fold Interpenetrated 3D pcu Topology Displaying Catalytic Activity

A new Cu(Ⅱ) coordination polymer, [Cu2(mip)2(bmix)]n(bmix = 1,4-bis(2-methylimidazole-1-ylmethyl)benzene, H2 mip = 5-methylisophthalic acid), has been hydrothermally synthesized and characterized by elemental analyses, IR, TGA and single-crystal X-ray diffraction. The title compound belongs to the triclinic system, space group P1 with a = 9.435(5), b = 12.241(6), c = 13.666(6), β = 94.396(8)o, V = 1565.5(13) 3, Z = 2, C34H30Cu2N4O8, Mr = 749.70, Dc = 1.590 g/cm3, μ = 1.419 mm-1 and F(000) = 768. The title metal-organic coordination polymer exhibits the first two-fold interpenetrated pcu topological structure assembled by two types of dinuclear copper(Ⅱ) clusters and a flexible bis(imidazole)-based ligand. In addition, the fluorescence and catalytic performances of the complex for the degradation of Congo red azo dye in Fenton-like process were presented.     

基于SIFT匹配的全局运动估计方法

提出了一种基于SIFT(Scale invariant feature transform)匹配的全局运动估计算法.在SIFT初匹配的基础上,对每一个原始匹配特征点,利用所在尺度的邻域灰度信息,对其加权平均后再进行匹配,进而去除误配点.精炼后的匹配点集合作为求解全局运动参数模型的对应数据,采用最小二乘法计算模型参数.在...     

利用连续渗流理论构造股市指标波动模型及其讨论

本文引用连续渗流理论构造了股票市场指数波动模型,得到其特征函数收敛于Levy过程这一结论.并且在模型中也体现出了市场波动的"宽尾"现象.     

流量大小对混合流场特性等的影响

 在主、副气流各组份的流量比不变的情况下，改变输入氧碘化学激光器（COIL）光腔总气流流量，数值模拟给出了COIL拉伐尔喷管主、副气流混合状况和各物理量的分布等，通过对这些结果进行对比分析得出：输入COIL光腔总气流流量增加三倍，氧碘气流的混合状况稍稍变差，但Mach数和密度等的分布和变化规律基本不变。     

一个函数不等式“繁殖”出来的数列不等式“蘑菇群”

数列不等式的证明是高考数学中常见的难点问题，传统的证法中大都局限在放缩法、数学归纳法等，新教材将导数引入之后为某些数列不等式的证明开辟了一条全新的途径．     

文物红色系颜料高光谱识别指数研究

红色系矿物颜料曾被艺术家们大量地使用在古画和古建筑上。正确地识别出不同种类的红色系颜料对于文物监测与修复具有重要意义。传统的颜料识别主要依靠化学分析,不仅识别速度慢、识别范围小,而且对文物进行取样操作会造成文物的永久损伤。高光谱技术对颜料进行无损识别可以很好地解决这些问题。选用辰砂、胭脂、银朱、朱膘、朱砂、赭石、赭粉、铁红、土红、西洋红10种红色系矿物颜料作为研究对象,使用地物光谱仪在暗室中获取这10种红色系颜料在350～2 500 nm波段内的高光谱数据原始数字（DN）影像,经反射率校正,得到可直接用于光谱分析的反射率数据及光谱曲线。基于10种红色系颜料不同的光谱曲线特性,分两步筛选获取被区分颜料即目标颜料的光谱特征波段。取目标颜料光谱曲线的极值点作为特征波段,可以筛选得到目标颜料的初选光谱特征波段。将其余9种颜料在初选光谱特征波段上对应的反射率与目标颜料在此波段上的反射率做差,对于差值,筛去离群值后求平方和,不同波段对应不同的差值平方和,选取差值平方和较大的前4个波段作为优选后的光谱特征波段。基于归一化光谱指数模型公式[NDSI=（R_a-R_b）/（R_a+R_b）,R_a和R_b分别为目标颜料在光谱特征波段a和b处的反射率值]对10种红色系颜料分别构建归一化光谱指数,将目标颜料与其余9种红色系颜料在同一光谱特征波段处计算得到的光谱指数进行对比分析,计算目标颜料光谱指数与其余颜料光谱指数的区分度,以此作为评价区分效果的指标。对于最终优选出的4个光谱特征波段,可构建6个归一化光谱指数,选择最小区分度最大的归一化光谱指数作为目标颜料的光谱特征指数。研究结果显示,在通过各自的光谱特征指数进行区分时,每种目标颜料与其他颜料的最小区分度都保持在0.7以上（大于0.5可认为区分明显）,说明上述方法可以对各红色系颜料进行准确区分,对于文物颜料的快速准确识别具有实践意义。     

起爆方式对非圆截面装药结构释能特性的影响

为了研究不同起爆方式下非圆截面装药结构的释能规律,采用AUTODYN软件开展了非圆截面装药结构在不同起爆方式下的释能特性数值模拟,分析了起爆方式对爆轰波形演变、破片质量、破片初速的影响。结果表明：由于装药结构的特殊性,采用端部单点起爆时装药能量分布不均匀,部分区域产生大量的无效小质量破片,且不同位置处的破片初速波动较大;采用端部两点和端部三点起爆时,能够对爆轰能量起到匀化效果,减少无效破片数量,提升破片初速的一致性。由此证明通过调整起爆方式可以对非圆截面装药结构的能量输出结构进行有效调控,对其周向能量场起到匀化效果。