卟啉分子识别中的非共价键相互作用

卟啉由于其特殊的分子识别性能在超分子材料化学领域得到了广泛的应用。本文综述了近年来卟啉化合物的分子识别研究,详细介绍了卟啉化合物进行分子识别过程中的非共价键相互作用,重点探讨了氢键、配位、π-π堆积以及静电等相互作用在卟啉分子识别中的作用,并对卟啉分子识别的前景进行了展望。     

检测金属离子的R-S-F结构型荧光分子传感器研究进展

Receptor-Spacer-Fluorophore(R-S-F)结构型荧光分子传感器是由可选择性结合客体的主体基团与传递信号的荧光团通过桥联基团连接而成的一类分子传感器,结合了超分子在分子识别中良好的选择性和荧光信号的高灵敏度两个优点,成为一类可用于检测金属离子并具巨大发展潜力的新型光学敏感材料.以超分子主体化合物...     

新型环糊精衍生物的合成及应用

简要介绍了环糊精化学的产生与发展、环糊精化合物的结构特征、性能及应用。详细介绍了新型环糊精超分子聚合物的制备及在波谱分析中的应用;新型环糊精衍生物的制备及在分析分离科学中的应用;环糊精衍生物的超分子组装及应用。并对环糊精化学的发展进行了展望。     

基于杯[4]芳烃基超分子凝胶组装进展

超分子凝胶是化合物通过非共价键作用组装成的物理凝胶,具有突出的相变可逆和对外界刺激的灵敏响应。在化合物中引入新的作用位点或新的功能基团,开发新非共价键作用方式和组装方式,以便提高超分子凝胶的性能是当前该领域的研究热点。杯[4]芳烃具有空腔可调、构象可变、结构易修饰、合成方便等优点,将杯[4]芳烃片段引入超分子凝胶提高了凝胶的性能,拓展了凝胶的应用范围。在金属离子、阴离子、主客体、胆固醇片段、酸等不同驱动力作用下,杯[4]芳烃衍生物组装成凝胶。介绍了杯[4]芳烃衍生物的制备方法、凝胶形成机理及其刺激响应性,总结了杯[4]芳烃超分子凝胶在分离、提纯、药物捕捉释放及作为凝胶电解质等方面的应用,对杯[4]芳烃基超分子凝胶的发展进行了展望。     

基于β-环糊精的分子印迹技术识别机理及评价手段

β-环糊精是一种应用较为广泛的生物相容性强的超分子化合物,将环糊精与分子印迹技术相结合,有助于人工合成所需要的智能型主体分子,能够有效地推动分子印迹技术的发展.首先介绍了基于β-环糊精的分子印迹技术的基本原理,并对其识别机制分别从交联剂的选择、模板分子大小以及溶剂的选择3个方面进行阐述；然后分别从电化学法、光谱法、色谱法以及静态吸附法4个方面对MI-β-CDs的选择性进行评价简介；最后对该领域的发展前景进行了展望.     

金属表面均三嗪二硫醇纳米聚合薄膜研究进展

综述了均三嗪二硫醇类化合物纳米聚合薄膜在各种金属基底表面的光聚合、热聚合、蒸发聚合及电化学聚合制备方法及在金属防护、材料间粘接、润滑特性、介电特性、超疏水和作为重金属离子处理剂等方面的应用。对该类化合物在不同金属表面的吸附作用和聚合机理进行了归纳、讨论与分析。提出了通过对该类三嗪二硫醇化合物分子进行改性研究,可在金属表...     

基于杯吡咯及其衍生物的化学传感器研究进展

杯吡咯是近年来一类新兴的超分子主体化合物,由于其独特的结构和理化性质,使得杯吡咯及其衍生物在识别金属离子、阴离子和中性小分子方面应用广泛。通过引入不同基团、改变其空腔大小得到的主体可以与不同大小、不同性质的客体分子相匹配,可作为敏感材料应用于离子选择电极、离子敏感场效应管、压电晶体、离子光导膜等多种类型的化学传感器上,对各种阴离子和中性分子的识别和检测。     

新型Schiff碱的应用研究进展

介绍了各类Schiff碱的结构特征、Schiff碱的结构与性能的关系以及对Schiff碱进行结构修饰的方法。综述了近年来各类Schiff碱的常用制备方法及其在配位化学、分析化学、光学、电化学、超分子化学和生物医药等方面的应用。提出了Schiff碱研发存在的问题,分析了其发展趋势。     

分子自组装膜在电分析化学中的应用进展

本文介绍了分子自组单层膜、多层膜和双层磷脂膜在电分析化学和生物传感器方面的研究应用进展。     

两种新型氢键诱导液晶材料的合成及表征

以对氨基苯甲酸、对硝基苯甲醛和吡啶衍生物为原料合成了两种新型氢键诱导液晶。用IR、1H-NMR和元素分析对所合成的化合物进行了结构表征,并用DSC和带热台的偏光显微镜分别对质子供体和超分子复合物复合前后的液晶行为进行了研究。结果表明:合成了目标化合物;IR结果证明了羧基和吡啶环间分子间氢键代替了羧基间的分子间氢键,复合物表现出分子的热力学行为;液晶行为研究证明了氢键复合物是典型的热致液晶且呈现明显的向列型液晶态,超分子液晶复合物较质子供体的液晶相范围宽且其相转变温度低于质子供体,说明分子间氢键起到了稳定液晶相态的作用。     

Flow-Induced Instabilities in Pump-Turbines in China

The stability of pump-turbines is of great importance to the operation of pumped storage power (PSP) stations. Both hydraulic instabilities and operational instabilities have been reported in PSP stations in China. In order to provide a reference to the engineers and scientists working on pump-turbines, this paper summarizes the hydraulic instabilities and performance characteristics that promote the operational instabilities encountered in pump-turbine operations in China. Definitions, analytical methods, numerical and experimental studies, and main results are clarified. Precautions and countermeasures are also provided based on a literature review. The gaps between present studies and the need for engineering practice are pointed out.     

Differences in coagulation in clotting of vascular access in hemodialysis patients

Arteriovenous graft (AVG) thrombosis is a frequent cause of graft failure. We evaluated coagulation protein concentrations, platelet function, and viscoelasticity factors in 20 hemodialysis (HD) patients with AVGs. The goal was to determine whether significant differences in protein concentrations, platelet function, and viscoelasticity factors exist among dialysis patients requiring frequent AVG declot procedures vs. those who do not. Twenty HD patients were enrolled: 10 frequent clotters (>3 declots in the previous year) and 10 were nonclotters. Patients on antiplatelets or chronic anticoagulation were excluded. Laboratories were drawn pretreatment and heparinase was added to counteract any potential heparin effect. Coagulation protein concentrations including tissue factor (TF), thrombin/antithrombin III complex (TAT), and prothrombin fragment 1 + 2 (F₁₊₂) were assayed. The time to clot onset was measured by force onset time (FOT). Platelet contractile force (PCF) measured the force produced by platelets during clot retraction, whereas clot rigidity was measured as clot elastic modulus (CEM). FOT, CEM, and PCF were measured by Hemodyne. Both groups had upregulation of the TF pathway, as TF, TAT, and F₁₊₂ levels were similarly increased over baseline levels. Hemodialysis patients with frequent AVG clotting had higher levels of both PCF and CEM compared with nonclotters. Additionally, the frequent clotters had a lower FOT relative to nonclotters, although both were considered in the normal range. Our study suggests that HD patients with recurrent AVG thrombotic events form clots with higher tensile strength compared with HD patients without recurrent graft thrombosis.     

Trends in alcohol-impaired driving in Canada

While a general decreasing trend in the number of persons killed in a traffic crash involving a drinking driver has occurred in Canada since the 1980s, it is evident that much of this decrease occurred in the 1990s. Since 2002, less progress has been made as the number of persons killed in crashes involving drinking drivers remains high. To better understand the current situation, this paper describes trends in drinking and driving in Canada from 1998 to 2011 using multiple indicators based on data collected for the Traffic Injury Research Foundation's (TIRF) Road Safety Monitor (RSM), the National Opinion Poll on Drinking and Driving, and trends in alcohol-related crashes based on data collected for TIRF's national Fatality Database in Canada. There has been a continued and consistent decrease in the number of fatalities involving a drinking driver in Canada. This remains true when looking at the number of fatalities involving a drinking driver per 100,000 population and per 100,000 licensed drivers. This decreasing trend is also still apparent when considering the percentage of persons killed in a traffic crash in Canada involving a drinking driver although less pronounced. Data from the RSM further show that the percentage of those who reported driving after they thought they were over the legal limit has also declined. However, regardless of the apparent decreasing trend in drinking driving fatalities and behaviour, reductions have been relatively modest, and fatalities in crashes involving drivers who have consumed alcohol remain high at unacceptable levels.     

Gender differences in publication productivity in psychology in India

An analysis of gender differences in psychology in India provides quantitative and qualitative assessment of R&D output contributed by psychologists with the indication of the trend of growth, skewness, relatedness, co-authorship pattern of productivity.     

离子液体中电沉积的研究进展

离子液体作为绿色溶剂和可设计性溶剂越来越受到重视.对电沉积来说,离子液体融合了高温熔盐和水溶液的优点.分别综述了AlCl3型离子液体、非AlCl3型离子液体和其他新型离子液体3类离子液体中电沉积的研究现状,在此基础上指出了目前尚存在的问题及今后的研究方向.采用离子液体进行电沉积能克服传统水溶液电沉积时存在的缺点,为电沉积领域找到了新的突破点,是一种很有应用前景的方法.     

高聚物银纹化的研究进展

结合最新的研究进展,对银纹引发、生长与断裂,银纹细观结构以及裂纹在银纹中的扩展等问题作了较全面的介绍和分析,对这一领域未来的研究方向和重点进行了展望。     

铁电陶瓷中电畴翻转研究进展

电畴为铁电陶瓷固有的独特微观组织特征之一,铁电陶瓷的许多性能均与其密切有关.综述了铁电陶瓷中的电畴结构,系统介绍了电场、机械作用引起的电畴翻转,概述了电畴翻转对铁电陶瓷断裂韧性的影响及其研究进展.     

Metrology in Chemistry in Germany

The system for Metrology in Chemistry in Germany is described. At the national standards level, a network of high-level chemistry institutes coordinated by the national metrology institute, PTB, provides the primary references for chemical measurements. A dissemination mechanism employs chemical calibration laboratories accredited within the framework of the German Calibration Service (DKD). They act as “multipliers” between the national standards level and the user level by providing the user with calibration means which are traceable to the SI via national standards. Traceability structures in clinical chemistry, electrochemistry, elemental analysis and gas analysis are described