苦参生物碱杀虫生物活性测定

以桃蚜等9种试虫为供试靶标，研究了苦参根提取物和苦参碱、氧化苦参碱、槐果碱、野靛碱的杀虫活性。试验结果表明：苦参生物碱具有一定的杀虫活性，9种试虫中，苦参根提取物对蚜虫的活性最高，其对蚕豆蚜的LC50为20．635mg／L；即使在最高剂量为4000mg/L时，也不能直接杀死粘虫、小菜蛾和棉铃虫。4种生物碱对朱砂叶螨活性均较低，LC50均大于2500mg／L。野靛碱是4种生物碱中杀虫活性最高的，对淡色库蚊、桃蚜、蚕豆蚜、褐飞虱和家蝇的LC50分别为172．431mg/L、207．667mg／L、85．212mg／L、266．179mg／L和763．224mg／L；而且对褐飞虱、桃蚜和家蝇的活性高于苦参根提取物，苦参碱对蚜虫的活性高于氧化苦参碱和槐果碱，槐果碱对淡色库蚊、褐飞虱和家蝇的活性高于苦参碱和氧化苦参碱。     

浅谈国内外钒催化剂的质量差异

从化学组分、强度、活性、物相结构、孔容积及孔径分布等方面，对国产S101-2H、S108-1H钒催化剂和进口LP120、LP110钒催化剂进行剖析、对比。结果表明，国产催化剂强度比进口催化剂低30％左右；国产催化剂测定活性与进口催化剂相近，但实际使用活性明显劣于进口催化剂；进口催化剂载体中存在方英石、硫酸铝钾相，而国产催化剂没有；进口催化剂孔径分布较宽，主要孔径分布在0．50～1．50μm，而国产催化剂孔径分布较窄，主要孔径分布在0．060～0．30μm，不利于反应气体在催化剂内部的扩散。鉴此，建议采用高温煅烧载体，降低其有机物含量；优化配方，填加无机粘结剂；改进成型设备等措施，提高催化剂的强度和活性。     

药物抗氧化作用对DNA发光动力学行为的影响

本文应用ＣｕＳＯ４－Ｐｈｅｎ－Ｖｃ－Ｈ２Ｏ２－ＤＮＡ化学发光体系观察药物对发光动力学行为的影响，研究了九种药物对ＤＮＡ损伤的保护作用，并对其药物结构对抗氧化能力的影响进行了分析。发现药物在该系统中的抗氧化作用有三种类型，提示它们可能在体内不同的反应过程中起不同的作用。在该系统中具有抑制ＤＮＡ损伤发光能力的药物，按其作用强弱依次为阿魏酸、丹参素、芦丁，茶多酚、ＳＯＤ、、丹参酮Ⅱ－Ａ，丹皮酚，五味子乙     

混合物MH-81状态方程的研究——从无限稀释活度系数预测混合物汽液平衡

本文由无限稀释活度系数求取混合物MH-81状态方程的二元相互作用参数,预测了二元混合物的汽液平衡,获得了较满意的结果。     

Investigation on the electrocatalytic characteristics of SnO_2 electrodes with nanocoating prepared by electrodeposition method

SnO2 electrodes have many advantages in the degradation of toxic or bio-refractory organic wastewater,and SnO2 is a kind of anode material which has the potential to be widely used.Electrocatalytic effi-ciency and service life of Ti\SnO2 electrodes are key factors that can influence its applications.In order to enhance the electrocatalytic characteristics of Ti\SnO2 electrodes,a type of electrocatalytic electrode with nanocoating was prepared by direct current(DC)electrodeposition method and thermal oxidati...     

色谱顶空法测活度系数及对三元极性体系液液平衡预测

用气相色谱顶空分析法测定 18组部分互溶三元极性体系在完全互溶区的 3个组分活度系数 ,由此拟合出 U NIQU AC过量自由焓模型参数 ,再用 U NIQUAC方程预测液液平衡。这一方法曾很好地用在水-正烷烃 -醇体系。将此法拓展到含醇、酮、酯 ,醚、卤烷烃和水等多种极性组分的三元体系液液平衡的预测 ,其结果与文献的液液平衡数据比较 ,平均均方根误差 1.4 1% ,表明本法对含极性组分的体系仍然可行     

Thermodynamic reassessment of the Cd−Zn system

The Cd−Zn system has been thermodynamically reassessed with the CALPHAD method by combining more recent experimental data, in particular the activities of zinc in the liquid phase. A good agreement is obtained between the calculated and experimental thermodynamic parameters as well asphase boundaries.     

含B2O3渣系的热力学计算模型

根据炉渣结构的共存理论和相图，推导了ＣａＯＢ２Ｏ３和ＦｅＯＦｅ２Ｏ３Ｂ２Ｏ３渣系的热力学计算模型。结果表明：（１）理论计算的ＣａＯＢ２Ｏ３渣系的作用浓度ＮＣａＯ及ＮＢ２Ｏ３与实测的活度ａＣａＯ及ａＢ２Ｏ３一致；（２）理论计算的ＦｅＯＦｅ２Ｏ３Ｂ２Ｏ３渣系的氧化能力ＮＦｅｔＯ与实测的炉渣ＦｅｔＯ的活度值相符合。这说明本文提出的热力学计算模型是合理的。     

Ligand Design in Atomically Precise Copper Nanoclusters and Their Application in Electrocatalytic Reactions

Metal nanoclusters (MNCs) are compositionally well-defined and also structurally precise materials with unique molecule-like properties and discrete electronic energy levels. Atomically precise ligand-protected Cu nanoclusters (LP-CuNCs) are one category of typical MNCs that usually demonstrate unique geometric and electronic structures to serve as electrocatalysts. However, the synthesis, application, as well as structure-performance relationship of LP-CuNCs are not adequately studied. Significantly, the ligands are essential to the geometric structure, crystal structure, size, and electronic structure of LP-CuNCs, which determine their physiochemical properties and applications. In this review, significant progress in the ligand design of LP-CuNCs, and their application in electrocatalytic reactions is introduced. The general basics of ligand-protected MNCs (LP-MNCs) are first introduced and the functions of ligands are emphasized. Subsequently, a series of different ligands for LP-CuNCs including thiolates, phosphines, alkynyl, polymers, and biomolecules are highlighted. Thereafter, their applications in different electrocatalytic reactions are discussed. It is believed that this review will not only inspire the design and synthesis of novel LP-CuNCs, but also contribute to the extension of their applications in electrocatalytic reactions and the establishment of accurate structure-performance relationships.     

Shape design of cerium oxide nanoparticles for enhancement of enzyme mimetic activity in therapeutic applications

Cerium oxide nanoparticles (CONPs), widely used in catalytic applications owing to their robust redox reaction, are now being considered in therapeutic applications based on their enzyme mimetic properties such as catalase and super oxide dismutase (SOD) mimetic activities. In therapeutic applications, the emerging demand for CONPs with low cytotoxicity, high cost efficiency, and high enzyme mimetic capability necessitates the exploration of alternative synthesis and effective material design. This study presents a room temperature aqueous synthesis for low-cost production of shape-selective CONPs without potentially harmful organic substances, and additionally, investigates cell viability and catalase and SOD mimetic activities. This synthesis, at room temperature, produced CONPs with particular planes: {111}/{100} nanopolyhedra, {100} nano/submicron cubes, and {111}/{100} nanorods that grew in [110] longitudinal direction. Enzymatic activity assays indicated that nanopolyhedra with a high concentration of Ce⁴⁺ ions promoted catalase mimetic activity, while nanocubes and nanorods with high Ce³⁺ ion concentrations enhanced SOD mimetic activity. This is the first study indicating that shape and facet configuration design of CONPs, coupled with the retention of dominant, specific Ce valence states, potentiates enzyme mimetic activities. These findings may be utilized for CONP design aimed at enhancing enzyme mimetic activities in therapeutic applications.

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