Syntheses,Structures, and Luminescent Properties of Two Zn~Ⅱ-organic Polymers Based on [Zn(ox)]_n Chains and Different Imidazole Linkers

Hydrothermal reactions of two imidazole derivatives(1,3,5-tib = 1,3,5-tris(1Himidazol-1-yl)benzene, 1,4-bimb = 1,4-bis(1H-imidazol-1-ylmethyl)benzene) and the ZnⅡ cations in the presence of oxalic acid(H2ox) afford two coordination polymers, namely, {[Zn(ox)(1,3,5-tib)]·2(H2O)}n(1) and [Zn1.5(ox)1.5(1,4-bimb)1.5]n(2). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction(PXRD) analyses. Both complexes 1 and 2 are based on the 1D zigzag [Zn(ox)]n chains, and their final structures are controlled by the two different imidazole linkers, which expanded the structure along different directions, finally giving a 3D dia net for 1 and a 2D sql layer for 2. Moreover, the luminescent properties of 1 and 2 have been investigated.     

Synthesis and Crystal Structure of a New Pr(Ⅲ)–K(Ⅰ) Heterometallic Oxalate Coordination Polymer

A new 3D heterometallic coordination polymer, namely [K2Pr2(C2O4)4·H2O]n(1), has been successfully synthesized under hydrothermal conditions. X-ray single-crystal diffraction determination reveals that 1 crystallizes in monoclinic system, space group P21/n with a = 12.060(4), b = 8.493(3), c = 15.776(5)(A), β = 93.235(3)°, V = 1613.4(9) 3, Z = 4, Mr = 730.12, Dc = 3.006 Mg/m3, μ = 6.581 mm-1, F(000) = 1368, the final R = 0.0283 and w R = 0.0866 for 2939 observed reflections with I 2σ(I). Complex 1 features an unusual 3D heterometallic coordination framework, in which oxalates exhibit three different coordination behaviours. Moreover, powder X-ray diffraction and thermal properties for 1 have also been investigated.     

Hydrothermal Synthesis and Structural Characterization of a Novel 3-D Open Framework Zinc Phosphate Microporous Compound(C_5N_2H_(14))·[Zn_3(OH_2)(PO_4)_2(HPO_4)]

One novel organically templated zincophophate(C5N2H14)·[Zn3(OH2)(PO4)2(HPO4)] has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction together with elemental analysis, infrared spectroscopy, thermogravimetric analysis, and powder X-ray diffraction. The title compound crystallizes in the monoclinic space group P21/n, with a = 9.7904(11), b = 14.0287(14), c = 11.8651(13) , β = 104.690(3), V = 1576.4(3) 3, Z = 4, T = 296(2) K, Mr = 601.31 and Dc = 2.533 g/cm3. The compound consists of a macroanionic [Zn3(OH2)(PO4)2(HPO4)]2- framework and(C5N2H14)2+ cations, and its structure is built up from ZnO3(OH2), ZnO4, HPO4 and PO4 tetrahedral units that result in 4, 8 and 10-ring channels.     

常见客体分子对笼型水合物晶格常数的影响

Natural gas hydrates are considered as ideal alternative energy resources for the future, and the relevant basic and applied research has become more attractive in recent years. The influence of guest molecules on the hydrate crystal lattice parameters is of great significances to the understanding of hydrate structural characteristics, hydrate formation/decomposition mechanisms, and phase stability behaviors. In this study, we test a series of artificial hydrate samples containing different guest molecules (e.g. methane, ethane, propane, iso-butane, carbon dioxide, tetrahydrofuran, methane + 2, 2-dimethylbutane, and methane + methyl cyclohexane) by a low-temperature powder X-ray diffraction (PXRD). Results show that PXRD effectively elucidates structural characteristics of the natural gas hydrate samples, including crystal lattice parameters and structure types. The relationships between guest molecule sizes and crystal lattice parameters reveal that different guest molecules have different controlling behaviors on the hydrate types and crystal lattice constants. First, a positive correlation between the lattice constants and the van der Waals diameters of homologous hydrocarbon gases was observed in the single-guest-component hydrates. Small hydrocarbon homologous gases, such as methane and ethane, tended to form sI hydrates, whereas relatively larger molecules, such as propane and iso-butane, generated sⅡ hydrates. The hydrate crystal lattice constants increased with increasing guest molecule size. The types of hydrates composed of oxygen-containing guest molecules (such as CO₂ and THF) were also controlled by the van der Waals diameters. However, no positive correlation between the lattice constants and the van der Waals diameters of guest molecules in hydrocarbon hydrates was observed for CO₂ hydrate and THF hydrate, probably due to the special interactions between the guest oxygen atoms and hydrate "cages". Furthermore, the influences of the macromolecules and auxiliary small molecules on the lengths of the different crystal axes of the sH hydrates showed inverse trends. Compared to the methane + 2, 2-dimethylbutane hydrate sample, the length of the a-axis direction of the methane + methyl cyclohexane hydrate sample was slightly smaller, whereas the length of the c-axis direction was slightly longer. The crystal a-axis length of the sH hydrate sample formed with nitrogen molecules was slightly longer, whereas the c-axis was shorter than that of the methane + 2, 2-dimethylbutane hydrate sample at the same temperature.     

用于荧光光谱测定的微量固体粉末样品制样优化*

为满足微量固体粉末荧光检测要求,采用薄层制样法,改变黏结剂种类、黏结剂的用量、涂层厚度以及后处理方法来进行其制样工艺优化。 结果表明:以聚乙烯醇做黏结剂、1∶5的固液比、在50 ℃烘干30 min、涂片次数3层的薄层制样优化工艺可满足荧光固体测样的要求。采用t检验比较固体样品池装样和薄层制样法的荧光检测结果发现两者无显著性差异,薄层制样优化工艺的需样量较样品池减少90%。     

粉末微波滤波器的制备和特性

利用通电导线的电磁感应和铜粉的趋肤效应,试制了在超导量子计算实验系统中使用的粉末微波滤波器.滤波器的频率响应随频率升高而平缓下降,在1GHz左右衰减至-80dB.我们分析了滤波器的原理,并通过改变参数对滤波器性能的变化进行了详细的研究.     

X射线荧光光谱(XRF)法测定土壤污染样品中9种重金属元素

采用粉末压片法制样,利用理学ZSX PrimusⅡX射线荧光光谱仪,用国家标准物质土壤(GSS系列)、沉积物(GSD系列)、环境保护部标准样品研究所研制的土壤标准样品GSB Z 50011-88(黑钙土)、GSB Z 50012-88(棕壤)、GSB Z 50013-88(红壤)、GSB Z 50014-88(褐土)、湖南污染土壤标准(GBW0732729)作标准样品,建立了X射线荧光光谱(XRF)法测定农业地质土壤污染物样品中的Cu、Pb、Cr、Ni、Zn、Co、As、Mn、V等9种重金属元素的方法,采用经验系数法校正谱线重叠干扰和基体校正。用3个土壤考核样品和环境保护部标准样品研究所研制的GSB07-3272-2015作为样品评估方法的准确度和精密度,结果符合《全国土壤污染状况详查土壤样品分析测试方法技术规定》中规定的Cu、Pb、Cr、Ni、Zn、Co、As、Mn、V元素检测方法质量要求。     

巯基乙酸锑(Ⅲ)配合物合成与晶体结构

以三氧化二锑和巯基乙酸在水溶液中反应合成了配合物HSb(SCH2COO)2,并通过元素分析、红外光谱、X射线粉末衍射进行了表征,利用单晶X射线四圆衍射法测定了晶体结构,结果表明该配合物晶体属于单斜晶系,C2/c空间群,晶胞参数为:a=1.40005(8)nm,b=1.19121(8)nm,c=1.23588(8)nm,β=126.822(1)°,V=1.6499(2)nm^3,Dc=2.439g·cm^-3,Z=8,R1=0.0250。并对X射线粉末衍射数据进行了指标化,其结果与单晶数据吻合。     

Li2+2xZn1-xSiO4水基溶胶-凝胶法合成及其离子导电性

用水基溶胶凝胶法制备了锂离子导体Li_2+2xZn_1-xSiO₄(0≤x≤0.5)。实验中对干凝胶的热稳定性进行了TG-DTG分析。XRD谱结果表明形成了与Li₃PO₄结构相关的固溶体Li_2+2xZn_1-xSiO₄。TEM结果则显示晶粒尺寸为50nm左右,并应用交流阻抗谱技术进行了样品烧结体的电性能测试。     

锂离子电池爆喷失效后残留粉末的研究

由电池挤压试验机得到不同荷电状态的电池爆喷失效后的残留粉末.经称量、水溶解和X射线衍射(XRD)测试,结果表明,随着电池荷电状态的提高,单位能量升高,电池燃烧温度上升和持续时间延长,其铜箔完好程度逐渐降低,粉末残余量逐渐减少.依据水溶解实验可将残留粉末分为不溶粉末和可溶粉末2种,其中不溶粉末较多,主要成分有C、Co和CoO;可溶粉末较少,主要成分有Li2CO3和LiF.随着电池荷电状态的提高,不溶粉末含量逐渐减少,而可溶粉末含量逐渐增多.