硝基甲烷在离子液体BMImBF4中的电还原特性

采用循环伏安等测试方法, 以铂微盘电极为工作电极, 研究了硝基甲烷在离子液体1-正丁基-3-甲基咪唑四氟硼酸盐(BMImBF4)中的电化学行为, 并探讨了温度和扫描速率等因素对硝基甲烷电化学特性的影响. 实验结果表明, 硝基甲烷在离子液体BMImBF4中的还原反应是受扩散控制的不可逆过程. 估算了不同温度下硝基甲烷在离子液体BMImBF4中的扩散系数D, 进而求得它的扩散活化能Ea约为39.5 kJ·mol-1.     

荧光各向异性法均相检测酸性、中性和碱性介质中的蛋白酶

荧光各向异性;罗丹明;蛋白酶;胰蛋白酶;胃蛋白酶;菠萝蛋白酶;蛋白酶抑制剂     

络合滴定法测定钙含量微型实验研究

利用微型滴定法测定含钙制品中的Ca2 含量,并对微型滴定法与常量滴定法的平行测定结果进行了比较。结果两种方法无显著性差异,F检验t检验结果均在允许范围内,相对偏差均小于2.0%,微型滴定法的精度达到常量滴定法测定水平,能满足化学分析要求。     

Gd_3Al_5O_(12)∶Eu~(3+)柠檬酸盐硝酸盐燃烧法合成及其发光性能研究

采用柠檬酸盐硝酸盐燃烧法,在较低的温度(900℃)下成功地合成单一晶相Gd3Al5O12∶Eu3+发光粉体,紫外激发荧光光谱分析表明,粉体615 nm和593 nm荧光发射源于Eu3+的5D0-7F2和5D0-7F1跃迁.该方法中各工艺条件(如pH值、柠檬酸/金属离子比、煅烧温度)对Gd3Al5O12∶Eu3+发光性能均有影响,通过试验得出了获得最佳发光性能荧光粉体的工艺参数.     

Dendritic Macroinitiator for the Ring—Opening Polymerization of γ—Benzyl L—Glutamate N—Carboxyanhydride

Much effort has been dedicated to the molecular design and synthesis of model proteins to define protein folding interactions and to develop protein-based materials. Among them, the ring-opening polymerization of -amino acid-N-carboxyanhy- drides (NCAs) has drawn much attention because the resulting artificial polypeptides have wide applications in biotechnology, biomineralization and diagnostics1, 2. It is well known that dendrimers are hyperbranched macromolecules possessing a very high co…     

吡咯基金属络合物的制备及其在有机合成中的应用

本文综述了近年来吡咯基金属络合物的研究进展, 详细讨论了σ~N-、σ~C-、π-型吡咯基金属络合物的制备方法, 以及各类吡咯基金属络合物在有机合成中的应用。     

合成重要中间体1,4位官能化化合物的简便方法

5,6-取代环烯醚2在乙腈的单重态氧反应有效的生成一系列1,4位官能化化合物3。1,4位官能化化合物为合成上重要的中间体。环烯醚2可以通过β-二酰基化合物1和1,3-二溴丙烷在稀碱(碳酸钾/丙酮)条件下缩合生成。     

反相离子对高效液相色谱法测定蔬菜中多菌灵残留量

建立了一种用HPLC测定蔬菜中多菌灵残留量的分析方法。样品中多菌灵经甲醇提取,在pH 1~2时用二氯甲烷液液净化,水相调至弱碱性,再用二氯甲烷提取,提取液经浓缩,癸烷磺酸钠离子对试剂处理后,用HPLC-DAD分离测定,外标法定量。对于50 g样品,定容至10 mL,进样量20μL,检出限为0.05mg/kg,样品回收率>80%,RSD<10%,能满足农药残留分析的要求。     

A Polymeric Iodiplumbate(Ⅱ) Templated by Conjugated Quaternary Ammonium: Synthesis, Band Structure and Optical Properties

A new lead(Ⅱ) iodide coordination polymer [(npq)(PbI3)]n 1 (npq = N-propyl- quinolinium) has been synthesized in the presence of npq as structure-directing reagent (SDA). Compound 1 crystallizes in the orthorhombic system, space group Pbca, with a = 19.158(4), b = 7.9909(16), c = 22.929(5) (A), V = 3510.2(12) (A)3, Z = 8, Dc = 2.877 g/cm3, F(000) = 2672, C12H14I3NPb, Mr = 760.14, μ(MoKα) = 14.872 mm-1, the final R = 0.0431 and wR = 0.1021 for 3678 observed reflections with I＞2σ(I). Structure determination indicates that the [PbI3]-n infinite chains in each unit cell shape the sketch of 1, which could be described as the result of face-sharing distorted PbI6 octahedra running along the b axis. Electrostatic interaction between conjugated organic counter-cations and inorganic moieties presents and contributes to the crystal packing. 1 was further characterized with IR and elemental analysis. Based on the crystal structure data, quantum chemical calculation with DFT method was used to reveal the electronic structure and optical property of 1.     

V（V）促进SO4^2-／ZrO2固体超强酸的制备及催化反应

用低温陈化的方法制得V（V）促进型SO4^2-／ZrO2固体超强酸（SZV），用流动指示剂法测定其酸强度，用IR，XRD和XPS进行结构表征，并将制得的催化剂用于催化乙酸和丙三醇的酯化反应．结果表明，低温陈化样品比常温陈化有更强的酸性和更高的催化活性，IR谱图中S—O键的伸缩振动峰显著增强，在600～650℃的焙烧温度下，低温陈化样品的晶体结构为ZrO2四方相，XPS图中Zx3d峰位出现较大的化学位移，表明低温陈化使SZV样品具有较高的酸性．