有机场效应晶体管应用于化学及生物传感的研究进展

有机场效应晶体管(OFETs)是以有机半导体材料作为有源层的晶体管器件。和传统的无机半导体器件相比,由于其具有成本低、易加工、柔性好和生物相容性而被人们广泛研究,在多种化学和生物传感器领域具有潜在而广泛的应用前景。本文简单介绍了OFETs的结构和工作原理,总结了近几年来OFETs在化学及生物传感方面的研究进展,最后对OFETs的发展方向做了归纳和展望。     

Kinetic aspects of chemical control over flame propagation in combustible gases

Kinetic aspects of controlling ignition and flame propagation parameters in the gas phase by chemical methods are considered. The efficiency of the chemical methods is due to the branched chain character of gas-phase combustion reactions and the dominant role of the competition between chain branching and chain termination in these processes.     

高效液相色谱法同时测定香兰素与邻位香兰素

建立了同时测定香兰素和邻位香兰素的高效液相色谱法.考察了流动相组成、柱温等因素对分析效率的影响.在流动相为5% 乙酸-乙腈(60 :40,体积比),流速1.0 mL/min,柱温25 ℃的优化条件下,香兰素和邻位香兰素可在5 min内实现分离.测定结果表明,香兰素和邻位香兰素在10 ～240 mg/L范围内线性关系良好...     

苯磺酸氨氯地平对映体在Chiralcel OJ柱上的色谱保留及拆分特性

在Chiralcel OJ手性柱上对苯磺酸氨氯地平对映体进行分离研究.考察了在正己烷流动相体系中,不同碳数、不同立体结构的醇类添加剂以及不同醇含量对分离结果的影响,同时还考察了流速及柱温对分离的影响.并通过色谱保留及热力学行为研究对药物手性识别机理进行了探讨.结果表明,在正己烷-异丙醇(90:10,体积比)为流动相,流...     

微波灰化/DUO-ICP-AES测定残渣燃料油中的铝、硅、钒

采用微波灰化技术消解残渣燃料油,用全谱直读DUO-ICP-AES同时测定残渣燃料油中的铝、硅、钒,优化了仪器工作参数和实验条件.结果表明,在质量浓度0 ～25.0 mg/L范围内铝、硅、钒的线性关系良好(r=0.999 70 ～0.999 99),检出限、回收率和相对标准偏差分别为0.005 ～0.050 mg/L、8...     

Experimental and theoretical study on the reaction of bicyclo[2.2.1]hept-5-en-endo-2-ylmethanamine with glycidyl ethers

Reactions of bicyclo[2.2.1]hept-5-en-endo-2-ylmethanamine with phenyl, 4-methylphenyl, 3-methylphenyl, 2-methylphenyl, 4-methoxyphenyl, cyclohexyl, and cyclohexenyl 2,3-epoxypropyl ethers gave the corresponding N-mono- and N,N-bis(3-R-oxy-2-hydroxypropyl) derivatives. The structure of the newly synthesized amino alcohols and regioselectivity of oxirane ring opening were determined by IR spectroscopy, ¹H and ¹³C NMR, and mass spectrometry. The reaction mechanism was studied by quantum chemistry at the PCM/B3LYP/6-31G(d) level of theory.     

Five-membered oxaza heterocyclic compounds on the basis of epoxides and aziridines

The review summarizes methods for the synthesis of 1,3-oxazolidin-2-ones, 1,3-oxazolidines, and dihydro-1,3-oxazoles from epoxides and aziridines. Possible applications of N,O-containing heterocycles in medicinal and organic chemistry as biologically active substances and intermediate products for their preparation are considered.     

The study of the interaction between chitosan and 2,2-bis(hydroxymethyl)propionic acid during solid-phase synthesis

New polymer salts and N-acetylated chitosan derivatives are prepared in an extruder by the method of solid-phase synthesis via the interaction of chitosan and 2,2-bis(hydroxymethyl)propionic acid. The effect of the initial component ratio and temperature on the yield and structure of the target products is studied. Joint deformation of solid components at room temperature is found to cause the quantitative formation of salt bonds between carboxylic groups of the acid and amino groups of chitosan. At elevated temperatures of synthesis, the corresponding acetylated derivatives with a degree of substitution of amino groups varying from 0.16 to 0.43 are prepared. The relaxation and phase transitions in the polymer salts and acetylated chitosan derivatives and their sorptional activity are studied. The films prepared from aqueous solutions of the new salt modification of chitosan are characterized by a homogeneous structure and improved mechanical characteristics relative to those of the films based on chitosan acetates. An additional thermal treatment of the products of the solid-phase synthesis leads to the formation of crosslinked and water-swollen materials that can be used for the development of novel polymeric chitosan-based membranes and sorbents.     

Single-component silicon sealing materials

Single-component silicon adhesive sealant of cold vulcanization based on liquid polyorganosiloxane resins with terminal hydroxyl groups designed at the State Research Institute of Chemistry and Technology of Organoelement Compounds are presented. It was demonstrated that due to their high performance characteristics, in particular the wide range of working temperatures (from −90 to +300°C), these materials draw interest from both civilian and special fields of industry. Methods of producing single-component silicon adhesive sealants were considered.     

延误休假且修理延迟的可修系统的更换策略

研究了修理工多重延误休假且修理延迟的可修系统,假设系统故障后均不能"修复如新",系统在准备休假期间故障的概率为q,系统延迟修理的概率为1-P,以系统故障次数为更换策略,运用更新过程和几何过程理论,得出系统长期运行单位时间内平均停机时间的表达式,并通过数值例子验证了存在最优策略,使得平均停机时间最短.