三维多枝雪花状银粉的制备及催化性能

室温下,以聚乙烯醇为保护剂,采用抗坏血酸还原硝酸银,于水相中一步合成出三维多枝雪花状银粉。结合X射线粉末衍射(XRD)、扫描电子显微镜(SEM)等结构表征手段,对三维多枝雪花状银粉的微观结构进行详细分析,在此基础上提出其可能的形成机理。此外,三维多枝雪花状银粉在4-硝基苯酚催化加氢反应中还表现出优异的催化活性。     

Bu3P-CS2加合物与含不饱和键化合物的环化反应

Bu₃P-CS₂加合物与含不饱和键化合物(富电子炔类、磷酰基炔类、磷酸基烯类)以及醛进行一锅反应以较好的收率得到1,3-二硫环戊烯或1,3-二硫环戊烷衍生物.Bu₃P-CS₂加合物与偶氮化合杨和醛类进行类似反应却得到四氢噻二唑硫酮衍生物.对反应机理进行了讨论.     

稀土对大鼠尿液成分影响的核磁共振研究

目前,稀土生物效应的研究已进入了分子和细胞水平,但在活体动物内研究稀土的作用情况还不多见。稀土化合物随食物进入动物体内后,会对动物体内的器官、组织、细胞产生一定影响,将导致其体液容量、分布、电解质浓度等方面的变化。现代NMR技术是目前药理毒理学研究的有效手段之一,它具有简便、全面、快捷、非破坏性等优点,可用于对体液样品的检测和研究。本文采用现代核磁共振技术研究了稀土化合物硝酸镧灌胃给药后对Wistar大鼠尿液中代谢产物的影响,为阐明稀土化合物的毒理学机制和稀土的进一步开发利用提供理论依据。     

Design,synthesis, and biological evaluation of 2-benzylpyrroles and 2-benzoylpyrroles based on structures of insecticidal chlorfenapyr and natural pyrrolomycins

Based on structures of insecticidal chlorfenapyr and antibiotic natural pyrrolomycins, a series of new 2-benzylpyrroles and 2-benzoylpyrroles (with or without ethoxymethyl group on the nitrogen of pyrrole) were designed and synthesized. These compounds or their parent compounds possess weak acidity and high lipophilicity, the two characteristic properties for uncouplers of oxidative phosphorylation; therefore, they are expected to have insecticidal and acaricidal activity. The bioassay result verified that both 2-benzylpyrroles 17 and 2-benzoylpyrroles 19 had varied degrees of insecticidal activity against oriental armyworm depending on the substituents on the benzene ring, but they did not give any acaricidal activity. Conversely, most N-alkylated compounds 18 and 20 exhibited both insecticidal activity and acaricidal activity, of which compound 18i [4-bromo-2-(2,4-dichlorobenzyl)-1-(ethoxymethyl) -5-(trifluoromethyl) - 1 \(H\) -pyrrole-3-carbonitrile] has IC \(_{50}\) as low as 10–20 mg L \(^{-1}\) on both activities.     

硫化物在铂电极上电氧化时空动力学的模型模拟和分析(英文)

根据铂电极上硫化物电催化氧化的反应机理,本文提取动力学模型并利用数值模拟研究了N型负微分阻抗(N-NDR)振荡区域的电极表面时空反应动力学.在均相体系模拟中观察到电流简单振荡和复杂振荡,其来源于双电层电势自催化与传质限制和毒化物种吸附负反馈的相互耦合.为了更接近于真实体系,在模型中考虑了平行和垂直于电极表面两个方向的传质过程.模拟结果发现了与实验现象具有相同演化行为的复杂斑图,如行波和闪烁波;同时在传质耦合体系模拟中观察到双电层电势双臂螺旋波.本研究工作促进对电化学体系时空斑图的理解和预测.     

The discovery of 3-(1-aminoethylidene)quinoline-2, 4(1H,3H)-dione derivatives as novel PSII electron transport inhibitors

Based on the structures of the 4-hydroxyphenylpyruvate dioxygenase inhibitor mesotrione and natural product fischerellin A, a series of imine derivatives of ( $E$ )-3-acyl-quinoline-2,4(1H,3H)-dione (6, 12 and 16) were designed, synthesized and systematically evaluated for their herbicidal activity. The bioassay results indicated that most of the synthesized compounds displayed good to excellent herbicidal activity, of which 6e, 6g, 6h, 6q and 6t exhibited more than 50 % inhibition against Brassica napus L., Amaranthus retroflexu or Digitaria adscendens at a dosage of $94\,\hbox {g}\,\hbox {ha}^{-1}$ or lower. The symptom of injured leaves in vivo, the high Hill reaction inhibitory activity of 6h in vitro ( $\hbox {IC}_{50}\,0.1\, \upmu \hbox {g}\,\hbox {mL}^{-1})$ and the computer-based binding model of compound 6h with D1 protein in photosystem II (PSII) reaction centre suggest this novel structure to likely be a new type of PSII electron transport inhibitor. Thus, we have found a novel type of diketone enamine structure targeted at the PSII reaction centre.     

不同采收期盘龙七中岩白菜素的含量比较

采用高效液相色谱法测定不同采收期盘龙七中岩白菜素的含量,进行比较,确定其最佳采收时期.色谱柱为Kromasil-C18(4.6mm×150mm,5μm),流动相为乙腈-0.2％％磷酸溶液(V/V,10∶90),流速为1.0mL/min,检测波长275nm;柱温35 C.结果表明,不同采收期盘龙七中岩白菜素含量变化较大,6月盘龙七中岩白菜素含量最低为2.34％,9月盘龙七中岩白菜素的含量最高为6.06％.以岩白菜素含量为指标,盘龙七的最佳采收期为9月.     

高质量大面积石墨烯的化学气相沉积制备方法研究

石墨烯因其奇特的能带结构和优异的物理性能而成为近年来大家研究的热点, 但是目前单层石墨烯的质量与尺寸制约了其实际应用的发展. 本文采用常压化学气相沉积(CVD)方法, 基于铜箔衬底, 利用甲烷作为碳源制备了高质量大面积的单层与多层石墨烯. 研究发现: 高温度、稀薄的甲烷浓度、较短的生长时间以及合适的气体流速是制备高质量、大面积石墨烯的关键. Raman光谱, 扫描电子显微镜、透射电子显微镜等表征结果表明: 制备的石墨烯主要为单层, 仅铜箔晶界处有少量多层石墨烯. 电学测试表明CVD制备的石墨烯在低温时呈现出较明显的类半导体特性; 薄膜电阻随外界磁场的增大而减小.     

Simulation of Electromagnetic Wave Logging Response in Deviated Wells Based on Vector Finite Element Method

The vector finite element method of tetrahedral elements is used to model 3D electromagnetic wave logging response. The tangential component of the vector field at the mesh edges is used as a degree of freedom to overcome the shortcomings of node-based finite element methods. The algorithm can simulate inhomogeneous media with arbitrary distribution of conductivity and magnetic permeability. The electromagnetic response of well logging tools are studied in dipping bed layers with the borehole and invasion included. In order to simulate realistic logging tools, we take the transmitter antennas consisting of circular wire loops instead of magnetic dipoles. We also investigate the apparent resistivity of inhomogeneous formation for different dip angles.     

无机及分析化学实验室管理的实践和探索

浙江大学无机及分析化学实验室在日常管理和教学辅助工作中开展了一系列的实践和探索,如开设循环实验、关注实验细节、加强安全教育与考核等。本文分析和总结了在实验室资源最优化、节约药品、保障仪器设备的运行、注重安全管理等方面所采取的一些行之有效的做法。