大肠杆菌的共振散射光谱研究

研究了大肠杆菌的共振散射光谱.它在470nm、510nm和730nm产生三个瑞利散射峰.当激发波长为470nm(6.38×1014Hz)时,大肠杆菌溶液在470nm(6.38×1014Hz)和940nm(1/2×6.38×1014Hz)分别产生一个瑞利散射峰和一个1/2分频散射峰;当激发波长为510nm(5.88×1014Hz)时,在510nm产生一个共振散射峰;当激发波长为730nm(4.11×1014Hz)时在365nm(2×4.11×1014Hz)和730nm(4.11×1014Hz)分别产生一个2倍频散射峰和一个共振散射峰.分频散射和倍频散峰与共振散射峰具有相似的散射行为.大肠杆菌的浓度在0.074～38×108个/mL范围内与共振光散射强度I470nm、I510nm、I730nm成良好线性关系.     

亮黄共振光散射法测定微量蛋白质

基于蛋白质对生物染色剂亮黄的共振光散射的增强效应,拟定了一种测定蛋白质的共振光散射法。在pH 2.5的Britton Robison缓冲溶液中,亮黄在510 nm处的共振光散射增强与蛋白质浓度呈线性关系。对牛血清白蛋白,线性范围为0.25~11.5 mg·L-1,检出限48μg·L-1。方法用于合成样品和人尿样品中蛋白质的测定,结果满意。     

液相卤化银纳米微粒的界面荧光和共振散射光谱特性

液相卤化银纳米微粒的共振散射光谱和发射光谱表明,AgCl和AgBr纳米微粒均在330,400,470和680nm处产生4个共振散射峰,在340,400和470nm处产生三个荧光峰．Ad纳米微粒在340,400,437,470和680nm处产生5个共振散射峰;除在340,400和470nm处产生3个荧光峰外,在434nm处有一最强的荧光峰．卤化银纳米微粒体系的浓度对共振散射信号的影响与浓度对荧光强度的影响一致,Aga,AgBr和AgI体系的共振散射光信号强度分别约为荧光信号的110,130和80倍,即荧光与共振散射之间存在相关性．提出了液相AgX纳米微粒荧光产生机理,解释了荧光与共振散射之间存在相关性的原因．     

痕量新霉素的共振散射光谱分析

在pH值5.9 NaAc-HAc缓冲介质中,十二烷基苯磺酸钠与新霉素相互作用形成粒径约为160±12 nm的缔合微粒,在320、340、420、470 nm有4个共振散射峰.新霉素浓度在0.076~6.840μg/mL范围内与470 nm处的共振散射强度成正比,检出限为0.03μg/mL.该法具有选择性较好、灵敏度较高、快速、简便等特点,用于市售滴耳液和尿液分析,结果满意.     

DNA的亮绿共振光散射法测定

研究了在表面活性剂十六烷基三甲基溴化铵（CTMAB）的存在下，碱性染料亮绿（BG）与小牛胸腺脱氧核糖核酸（ctDNA）体系结合反应及其共振发光光谱；在pH7.3-7.6范围内，亮绿在核酸分子表面进行长距组装后，在470nm产生共振光散射（RLS）增强峰，其发光强度与DNA浓度呈线性关系；方法已成功地应用于合成样品的测定。     

银纳米微粒共振散射光谱法测定羟基自由基及其应用

以柠檬酸三钠做还原剂,采用微波高压法制备了银纳米微粒。用高速离心纯化除去过量的柠檬酸三钠获得了纯银纳米微粒。纯银纳米微粒的共振散射峰位于470nm处。在pH4.0的HAc-NaAc缓冲溶液中,Fenton反应产生的羟基自由基可氧化银纳米微粒生成银离子,导致470nm处的共振散射光强度降低。过氧化氢的浓度在0.27-7.56gmol／L范围内与银纳米微粒470nm处的共振散射强度降低值△I470nm呈良好的线性关系,回归方程为△I470nm=24.3C＋13.8,相关系数为0.9959,检出限为0.23μmol／L。该方法用于筛选羟基自由基的清除剂,获得了满意的结果。     

依波西隆蓝与蛋白质作用的共振光散射光谱及其分析应用

微量蛋白质对依波西隆蓝的共振光散射产生增强作用，且增强程度与蛋白质浓度有良好的线性关系，由此建立了测定蛋白质的灵敏共振光散射分析方法。利用该方法测定合成样品和血清样品中的蛋白质，均获得了可靠的分析结果。     

碳纳米微粒的共振散射光谱研究

液相碳纳米微粒的共振散射光谱实验表明,当碳浓度小于360mg/L时,它在400、470、510和940nm产生4个共振散射峰;浓度大于900mg/L时无共振散射、碳微粒浓度在0．45－45mg/L范围内与共振散射光强度I470nm成良好的性关系,研究了光源和扫描速度对液相碳纳米微粒共振散射光谱的影响。结果表明,光源的发射强度分布不一是产生共振散射光谱峰的一个重要因素,并结合已有的实验结果提出了界面共振吸收和黑白纳米微粒共振散射概念,解释了碳纳米微粒体系的共振散射光谱。     

蛋白质-SDS-罗丹明B体系的共振光散射光谱及其分析应用

研究了阴离子表面活性剂十二烷基硫酸钠(SDS),阳离子染料罗丹明B,与蛋白质相互作用的共振光散射(RLS)光谱及用于蛋白质的测定.实验表明,在pH 4.35的酸性介质中,SDS的共振光散射强度较小,它与蛋白质结合后,共振光散射强度能得到增强,但加入阳离子染料罗丹明B后,共振光散射强度显著增强.在λ=332.0 nm处,ΔIRLS最大,并且增强的共振光散射信号与蛋白质的浓度成正比.据此建立了一种测定蛋白质的新方法,该方法灵敏度高,对HSA的检出限达到1.9 ng/mL,线性范围为0.01～5.0 μg/mL.用于人血清样品中蛋白质的测定,回收率为94.0%～105.5%.     

用铬黑T作为共振光散射探针测定蛋白质

研究了金属指示剂铬黑T（EBT）作为共振光散射探针测定蛋白质的分析方法。实验表明，在pH=4.10的Britton-Robinson缓冲溶液条件下，铬黑T只有极弱的光散射，它与蛋白质结合后有强烈的共振光散射作用。在λ=375nm处，光散射强度最大，光散射强度与蛋白质的浓度成正比。据此建立了一种测定蛋白质的新方法。该方法简便、快速、灵敏度高，对HSA的检出限达到39μg/L;线性范围为0－15mg/L，用于人体血清样品的分析并用考马斯亮蓝法比较，取得了令人满意的结果。同时亦研究了牛血清白蛋白（BSA）、λ球蛋白、鸡蛋白蛋白、溶菌酶与染料EBT之间的作用。比较了2种不同类型的荧光仪器绘制的共振光散射光谱，并探讨了共振光散射的机理。     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...     

微量元素与疾病诊断治疗的研究现状及展望

对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述，包括：微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。     

Synthesis and Optical and Redox Properties of Symmetric and Asymmetric BODIPYs

Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.     

Conformations and steric and stacking interactions of trisubstituted ureas and thioureas with alkyl and phenyl groups

The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R₂UPh type and -thioureas of the R₂TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

Ferrocene and ferrocenium modified clays and their styrene and EVA composites

In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.     

钒与糖代谢及糖尿病

微量元素钒作为生物体内必需元素，经证实有很重要的生理学功能，与机体糖代谢有十分密切的关系，且能降低糖尿病动物模型的高血糖，极有可能被开发为治疗糖尿病的药物。     

含茂基苯并三氮唑基镧系有机配合物的合成及表征

三茂基镧系化合物和苯并三氮唑在四氢呋喃中反应,合成了7个未见文献报道的含茂基苯并三氮唑基镧系有机配合物,经元素分析、IR和MS测定,从有关数据推测了这类配合物的可能结构。