Synthesis, Crystal Structure and Fluorescent Property of One New Complex [Na2（2-benzoylbenzoato）4（Phen）2（H2O）2]·H2O

One binuclear sodium(Ⅰ) complex [Na2(2-benzoylbenzoato)4(Phen)2(H2O)2]·H2O has been synthesized with 2-benzoylbenzoic acid and 1,10-henanthroline as ligands. The crystal structure was determined by X-ray diffraction. The crystal belongs to the triclinic system with space group P , a = 1.08096(8), b = 1.09619(8), c = 1.09740(8) nm, α = 79.0600(1), β = 71.0450(1), γ = 62.0540(1)o, V = 1.08533(1) nm3, Dc = 1.421 g/cm3, Z = 2, F(000) = 484, GOOF = 1.036, the final R = 0.0363 and wR = 0.0961. The crystal structure shows that two neighboring sodium(Ⅰ) ions are linked together by two bridging water molecules, and each end position is coordinated with one 1,10-phenanthroline molecule and one 2-benzoylbenzoato to form a binuclear structure. Each sodium(Ⅰ) ion in the molecule is coordinated with five atoms to give a distorted trigonal bipyramid. The fluorescence property of the title complex is also discussed.     

基于银纳米粒子/氧化石墨烯复合薄膜制备TNP电化学传感器

利用改进的Hummers法制备了氧化石墨烯(GO), 以葡萄糖为还原剂直接在GO表面沉积银纳米粒子(AgNPs)得到性能稳定的AgNPs/GO纳米复合材料;基于该纳米复合材料修饰电极构建了一种新型的2, 4, 6-三硝基苯酚(TNP)电化学传感器。采用原子力显微镜(AFM)、扫描电镜(SEM)、透射电镜(TEM)、紫外可见光谱(UV-Vis)和交流阻抗(EIS)等多种方法对纳米复合薄膜进行了表征;并研究了TNP在复合薄膜修饰电极上的电化学行为和动力学性质。结果表明, AgNPs/GO对TNP有较强的电催化活性, 在复合薄膜修饰电极出现一灵敏的氧化峰和3个还原峰;利用氧化峰可对TNP进行定量分析。同时整个电极过程明显不可逆, 电极反应受到吸附步骤控制;复合膜电极表面覆盖度为5.617×10^-8 mol·cm^-2, 在所研究电位下的速率常数为9.745×10^-5 cm·s^-1。在pH 6.8的磷酸缓冲液中, 当富集电位为-0.70 V, 富集时间为60 s;TNP氧化峰电流与其浓度在5.0×10^-9~1.0×10^-7 mol·L^-1范围内成良好线性关系, 相关系数为0.995 8, 检出限可达1.0×10^-9 mol·L^-1。所制备的电化学传感器稳定性和选择性较好;用于实际水样中TNP的现场快速检测, 加标回收率在 97.6%~103.9%之间。     

有机相中脂肪酶催化糖酯合成的研究

研究了有机相中脂肪酶催化以单糖和乙酸乙烯酯或乙酸酐为底物的糖脂合成反应。建立了定性、定量检测糖酯的方法，考察了７种脂肪酶催化糖酯合成的活力，发现来自假单孢菌属的ＰＳＬ１的活力最高。研究了ＰＳＬ１对不同单糖底物的选择性，发现对甘露醇的选择性最好，转化率可达９５％。研究了反应体系中的含水量对糖酯合成的影响，探讨了酶浓度和温度对反应的影响。     

N-(2-甲基-6-乙基苯基)丙氨酸对映体的毛细管电泳分离

采用高效毛细管区带电泳法,以β-环糊精及其衍生物作为手性选择剂,对外消旋N-(2-甲基-6-乙基苯基)丙氨酸(EMPA)的两个对映体进行了手性分离,比较了环糊精种类、环糊精浓度、电解质溶液pH值、温度和电场强度对分离的影响.实验结果表明,采用2,6-O-二甲基-β-环糊精为手性选择试剂,环糊精浓度为40mmol/L、电解质溶液pH=5.5及温度为20℃时分离效果最佳,对映体基本达基线分离,线性范围为20～200mg/L,最低检测限为10mg/L.     

CuAg纳米结构表面共存和Ag表面对甘氨酸的新吸附行为

在异质纳米结构表面发生的新现象是当前研究的热点.最近发现，尽管甘氨酸在纯Ag表面只 能作物理吸附，蒸镀在Cu表面的单层Ag岛却能在Cu的帮助下，出现对甘氨酸作化学吸附的能力，这种现象是溢流效应的一种反映.蒸镀在Ag表面的Cu岛也能帮助附近裸露的Ag表面获得 化学吸附甘氨酸的能力，虽然这里已不是单原子层的银了.结果说明这种溢流现象来源于CuA g在表面的纳米结构共存，而不只是这种共存的某个结构所特有的.但是，由于Cu的表面能大 于Ag，所以即使是在室温下，Cu岛也会逐渐地被一单层Ag原子完全覆盖，从而失去溢 关键词： 溢流 甘氨酸 Cu Ag(111)     

近红外光谱法预测烟草的pH值

用近红外(NIR)光谱技术直接扫描烟叶粉末,通过一阶导数+附加散射校正和偏最小二乘法(PLS)的处理,建立了预测烟草pH值的数学模型。该模型的内部验证决定系数(r~2)为0.8333,预测标准差(RMSECV)为0.0603;外部验证决定系数(r~2)为0.804,预测标准差(RMSEP)为0.0926;PLS模型的因子数为7。通过配对-t检验,该方法与标准方法测定的结果无显著性差异。该方法精密度高,可用于烟草pH值的快速预测,为烟草行业节省大量资金和显著提高工作效率。     

Three-Body Structure of 11Li

A variational calculation for neutron rich nucleus l1 Li is made in the ⁹Li + n + n model. The ⁹Li-neutron and neutron-neutron interactions are chosen to be of the Gaussian potentials with a repulsive core and an attractive tail. The strlicture and interparticle correlations are studied. A direct verification supporting neutron halo structure is found by inspecting the correlated densities.     

Synthesis,crystal structures,DNA binding and oxidative cleavage studies of copper(II) complexes of N2S2 tetradentate ligands

Two new copper(II) complexes with aminothioether ligands, [Cu(L¹)(ClO₄)](ClO₄) · 0.5H₂O (1) and [Cu(L²)(H₂O)](ClO₄)₂ · H₂O (2) (L¹ = 2-benzyl-1,3-bis(aminoethylthio)propane and L² = 2-(4-butylbenzyl)-1,3-bis(aminoethylthio)propane), have been synthesized and characterized. The single crystal X-ray diffraction analysis reveals that both 1 and 2 adopt distorted square pyramidal geometries. The binding modes of both complexes with calf thymus DNA were investigated by UV–Vis and CD spectroscopies. The results show that both complexes mainly adopt an electrostatic attraction binding mode with DNA and the binding constants are (1.62 ± 0.02) × 10³ and (2.02 ± 0.02) × 10³ M⁻¹, respectively. Both complexes are able to cleave pBR322 plasmid DNA efficiently in the presence of ascorbic acid and the activity of 2 is higher than that of 1. The DNA cleavage by 1 and 2 were inhibited strongly in the presence of DMSO and tert-butyl alcohol, which suggests that hydroxyl radicals are the reactive oxygen species for the cleavage.     

Synthesis and Crystal Structure of Nitrogen-rich Compound: 2,5,2′-triazido-1,1′-azo-1,3,4-triazole

Abstract  The title compound 2,5,2′-triazido-1,1′-azo-1,3,4-triazole(2) has been synthesized by the reaction of 2,5,2′-trichloro-1,1′-azo-1,3,4-triazole(1) with sodium azide. Its crystal structure was determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P−1 with a = 6.6604(13) ?, b = 6.7035(13) ?, c = 12.916 (3) ?, α = 98.13(3)°, β = 95.56(3)°, γ = 106.48° V = 541.68(18) ?³, Z = 2, C₄HN₁₇, Mr = 287.22, D _c  = 1.761 g cm⁻³, F(000) = 288 and μ(MoKa) = 0.140 mm⁻¹, the final R = 0.0553 and wR = 0.1541. X-ray analysis indicates a stronger delocalization of the azo π bond along the hypothetical N₄ moiety within the title compound than those in(E)-1,2-bis(2,6-diazido-9- azabicyclo[3.3.1]nonan-9-yl)diazene. Index abstract  The title compound 2,5,2′-triazido-1,1′-azo-1,3,4-triazole has been synthesized by the reaction of 2,5,2′-trichloro-1,1′-azo-1,3,4-triazole with sodium azide. Its crystal structure was determined by single-crystal X-ray diffraction. X-ray analysis indicates a stronger delocalization of the azo π bond along the hypothetical N4 moiety within the title compound than those in(E)-1,2-bis(2,6-diazido-9-azabicyclo[3.3.1] nonan-9-yl)diazene.