小分子配体诱导合成N,N-二苄基二硫代氨基甲酸镉(II)配合物及晶体结构

4,4'-联吡啶与二苄基二硫代氨基甲酸镉配合物[Cd(DBTC)₂]₂ (1)反应得到加合物[Cd(DBTC)₂(4,4'-bipy)] (2) (DBTC＝N,N-二苄基二硫代氨基甲酸), 通过晶体结构分析及红外光谱等研究其结构与性质. 结果表明: 引入小分子配体会破坏[Cd(DBTC)₂]₂ (1)的二聚结构, 加入吡啶则得到单核的吡啶加合物[Cd(DBTC)₂py] (3), 而引入4,4'-联吡啶后其结构变为新型的一维链状结构的配位聚合物2, 这种结构在二硫代氨基甲酸金属配合物中少见报道. 也比较了不同配体如吡啶及4,4'-联吡啶对Cd(II)及Zn(II)配合物结构的影响.     

Synthesis of 2,2＇-（Substituted Arylmethylene）bis（1,6,6-trimethyl 6,7,8,9-tetrahydrophenanthro[1,2-b]furan-10,11-dione） Derivatives

The reactions of tanshinone IIA with aromatic aldehydes have been investigated and several 2, T-（substituted arylmethylene） bis （1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]- furan- 10, 11-dione） derivatives were obtained,     

High-performance liquid chromatography of in vitro synthesized poly(ADP-ribose) on ion-exchange columns, separation of oligomers of varying chain length and estimation of apparent branching

Separated macromolecular fractions of in vitro synthesized poly(ADP-ribose) by liver nuclei were subjected to ion-exchange chromatography in a programmed high-performance liquid chromatographic elution system. The effects of ionic strength, pH and temperature on the separation of poly(ADP-ribose) chains were determined. Short chain oligomers (up to n = 11) were fractionated into individual components by baseline separation. Each fraction was analyzed for chain length. Trace amounts of Ado(P)Rib(P)Rib(P) found in phosphodiesterase digests were taken as indication of apparent branching. In phosphodiesterase digests of the shorter oligomers, besides traces of the above component, two other digestion products were also observed, presumably representing oligomer termini, one terminal fragment being dominant in short oligomers. Medium and long chain oligomers were partly resolved to individual components, and especially the long oligomers exhibited marked temperature dependent elution patterns. Apparent branching increased with increasing chain length up to about 3% for n = 44 and components presumably indicating termini diminished to mere traces. The adenine spectra of all fractions identified individual components.     

Visual detection of cysteine and homocysteine

The determination of cysteine and homocysteine levels is of great current interest for the monitoring of desease states. A new colorimetric method for the simultaneous detection of l-cysteine and l-homocysteine has been developed. A fluorescein derivative reacts with the above amino acids, producing their respective thiazolidines resulting in color changes. Interference from other amino acids and proteins is minimal.     

Bis­(ethyl­enedi­amine)copper(II) bis(O,O′‐diethyl di­thio­phosphate)

In the structure of the title compound, [Cu^II­(en)₂][(EtO)₂P(S)S]₂ (en is ethyl­ene­di­amine) or [Cu(C₂H₈N₂)₂](C₄H₁₀O₂PS₂)₂, the Cu atom lies on a center of inversion and is coordinated in a slightly distorted square coordination geometry by four N atoms from two ethyl­enedi­amine mol­ecules. The diethyl di­thio­phosphate moieties, (EtO)₂P(S)S^?, act as counter‐anions.     

马来酸酐封端聚碳酸亚丙酯的大分子偶联反应

自从 1 969年井上祥平[1] 发现二氧化碳 (CO2 )可以同环氧化合物直接共聚合成脂肪族聚碳酸酯(APC)以来 ,这一学科领域受到科学家的广泛关注[2～ 8] .这是因为CO2 所产生的温室效应 ,成为使全球变暖的主要因素[9,10 ] .已经确定CO2 使气侯变暖占诸多因素中的 66% .目前大气中CO2 的体积浓度为 345ppmv,由于人类的各类活动每年以 1ppmv的速度递增 .因此 ,降低CO2 排放量已成为全人类共同关注的热点之一 .另一方面 ,CO2 的固定化以及消耗、利用显然是一个应积极鼓励的研究课题 .目前人们已经将CO2 同环氧乙烷 (EO)、环氧丙烷 (PO)、环…     

生物合理设计光系统Ⅱ抑制剂研究(Ⅴ)——取代苯甲酰胺基丙烯酸乙酯和新型嘧啶酮类化合物的合成及其Hill反应抑制活性

基于Dl蛋白结构模型,设计并合成了取代苯甲酰胺基丙烯酸乙酯及有关成环化合物嘧啶酮,通过X射线衍射确定了2-芳基-5-乙氧甲酰基-6-甲硫基-4-嘧啶酮的结构.生物活性测定结果表明,部分化合物显示出一定的Hill反应抑制活性.     

固相微萃取参数选择及其对有机锡分析的影响

固相微萃取是一种新型的、不断发展和完善的样品前处理方法，它与其它技术联用可对多种样品基体中挥发、半挥发性有机化合物进行测定。目前，该技术在毒性金属有机化合物中的应用很少。本文分析参数选择对固相微萃取的影响的同时，还对其在有机锡化合物分析中的应用作了综述。     

土坯力学性能及受压本构模型研究

为获取传统土坯受压应力-应变特性,确定其数学表达式,针对湿制法和干打法制作的土坯开展了单轴抗压试验和三点抗折试验。分别从抗压、抗折强度、破坏机理以及应力-应变关系等方面分析了两类土坯的力学性能。结果表明,普通砌墙砖的抗压及抗折试验方法均适用于传统土坯,干打土坯的抗压强度为湿制土坯的3倍,抗折强度为湿制土坯的1.3倍,但湿制土坯的断裂能为干打土坯的2.5倍。受压初期,干打土坯的应力-应变曲线存在因土料压密而导致的下凹段,而湿制土坯未表现出该特性。基于两类土坯单轴受压状态下的应力-应变曲线特征,提出了土坯单轴受压本构模型,该本构模型与试验数据吻合较好,可用于土坯砌体结构的数值模拟研究。     

一种磁流变弹性体执行器的联合优化方法研究

磁流变弹性体（magnetorheological elastomer, MRE）执行器作为智能减振应用系统的核心元件,其结构的优化是决定执行器性能上限及系统控制成效的关键。针对目前MRE执行器优化方法及理论研究欠缺的问题,文中面向一款横向隔振的MRE执行器,基于其机械结构和有效磁路,以优越磁控性能、低功耗和快速响应时间为优化目标,提出了一种新的MRE执行器联合参数优化方法。首先,基于MATLAB和COMSOL的联合仿真,将遗传优化算法和电磁有限元分析方法进行有效结合,实现对MRE执行器的优化编程;其次,完成对器件的全局尺寸结构优化设计,使得器件具备优越磁控性能（526.21 mT）、低功耗（44.05 W）及快速响应（5.43 ms）;最后,通过搭建测试系统对优化后装配的MRE执行器进行测试和评估,验证了文中优化方法的可行性和有效性。提出的联合优化方法不仅适用于MRE执行器结构,还可为多领域减/隔振应用的共性MRE器件优化设计提供理论参考。