茜素红荷移分光光度法测定头孢克洛

以茜素红(ARS)为荷移试剂,采用分光光度法直接测定了头孢克洛(CFC),并研究了ARS-CFC络合物的可见光谱性质及最佳反应条件.CFC浓度在1.157～38.58μg/mL范围内遵循比尔定律,回归方程为A=0.1312683 p+0.01064(ρ:μg/mL),检出限0.56μg/mL,表观摩尔吸光系数5.77×...     

茜素红与头孢哌酮的荷移反应研究与应用

实验以茜素红(ARS)为荷移试剂,采用分光光度法研究了ARS与头孢哌酮(CPZ)形成络合物的光谱性质及其反应的适宜条件.实验结果表明:头孢哌酮在2.0～200 μg/mL范围内遵循比尔定律,回归方程为:A=0.0036 p+0.000095(p:μg/ml),检出限0.75μg/mL,表观摩尔吸光系数2.64×10(4)L·mol-1·cm-1,相关系数为r=0.9965,并初步探讨了反应机理.用实验方法对尿样及生物样品进行加标回收测定,回收率在95.4%～104.8%.     

克拉霉素与百里酚蓝荷移配合物的光度分析研究

利用克拉霉素与百里酚蓝在乙醇介质发生荷移反应,建立了荷移分光光度法测定克拉霉素含量的方法.结果表明,荷移反应生成1∶1型配合物,最大吸收波长为442 nm,表观摩尔吸光系数为ε=1.66×104L·mol-1·cm-1,克拉霉素测定线性范围为8.278～57.59 mg/L.     

克拉霉素与苯基荧光酮的荷移反应及其测定

本文建立了一种测定克拉霉素的荷移分光光度法,克拉霉素与苯基荧光酮(PF)在乙醇溶液中发生荷移反应,荷移络合物在波长519nm处有最大吸收,其表观摩尔吸光系数为1.70×104 L·mol-1·cm-1,荷移络合物的组成比为1∶1,稳定常数为2.86×104,药物浓度在5.0×10-6~7.0×10-5 mol/L范围内服从比耳定律,当克拉霉素浓度为4.0×10-5 mol/L时,8次测定结果的相对标准偏差(RSD)为0.46%,检出限为6.0×10-7 mol/L。利用该法测定了克拉霉素胶囊中有效成分的含量,回收率大于98%以上。     

Hg(Ⅱ)-SCN- -甲基紫三元络合物光度法测定牛奶中痕量的汞

用Hg(Ⅱ)-SCN~- -甲基紫三元络合物光度法测定牛奶中痕量的汞,该法灵敏度高,络合物的摩尔吸光系数ε=5.015×10~5 L/(mol·cm),汞浓度在0～8μg(50 mL)时与吸光度呈线性关系,线性回归方程为A=0.04693c 0.01816,相关系数r=0.9928,汞的回收率为97.0％～98.5％,检出限为0.0068μg/mL。     

紫色素荷移分光光度法测定阿奇霉素

提出了紫色素荷移分光光度法测定阿奇霉素。在乙醇介质中,阿奇霉素与紫色素生成的荷移络合物在546nm处产生一个强的吸收峰。在最佳反应条件下,吸光度与阿奇霉素的质量浓度在8.0~120mg·L-1范围内呈线性关系,检出限(3s/k)为2.6mg·L-1。该法用于分析市售阿奇霉素片剂,测定值与标示值相符。加标回收率在98.8%~101%之间,测定值的相对标准偏差(n=5)在1.7%~2.4%之间。     

琥乙红霉素与甲基红的荷移反应研究

研究了电子给体琥乙红霉素与电子受体甲基红之间的电荷转移反应,确定了反应的最佳条件,建立了一种快速、简便测定琥乙红霉素的荷移分光光度法。结果表明:琥乙红霉素与甲基红在乙醇-水介质中即可生成稳定的1∶1络合物,该络合物的最大吸收波长为421nm,表观摩尔吸光系数和稳定常数分别为1.48×104 L·mol-1·cm-1和1.445×105。琥乙红霉素浓度在2.0~84.0μg/mL范围内符合比耳定律,线性相关系数为0.9991,检出限为1.06μg/mL。该方法用于测定药物制剂中琥乙红霉素的含量,加标回收率为98.2%~101.6%。     

荷移反应分光光度法测定谷氨酸的含量

对谷氨酸与四氯对苯醌的荷移反应进行研究,确定了反应条件。在pH9.6硼砂缓冲溶液中,两者形成1∶1的络合物,其最大吸收波长为338nm,表观摩尔吸光系数为5.5×103L/mol.cm,线性范围为0～25μg/mL。该法用于测定味精中谷氨酸钠含量的测定,加标回收率为96.1%～101.8%,相对标准偏差不大于1.13%(n=6)。     

胱氨酸与7,7,8,8-四氰基对苯醌二甲叉的荷移反应研究

采用分光光度法研究了胱氨酸与7,7,8,8-四氰基对苯醌二甲叉(TCNQ)的荷移反应。通过实验可知,在硼砂缓冲溶液中,室温下反应30min可获得稳定的1∶1的络合物,其λmax=425nm,表观摩尔吸光系数ε=4.4×103 L·mol-1·cm-1,线性范围为10~40μg·mL-1,探讨了荷移反应的机理,研究了该荷移络合物的结合常数和热力学性质。应用拟定的方法测定了胱氨酸片中胱氨酸的含量,经t-检验法检验,结果与文献方法无显著性差异,回收率为94.54%~101.2%。     

5′-硝基-水杨基荧光酮与头孢哌酮的显色反应

采用分光光度法,以5′-硝基-水杨基荧光酮(5′-NSAF)为显色剂,研究了5′-NSAF与头孢哌酮(CPZ)的络合物的可见光谱性质及反应条件。实验结果表明:头孢哌酮在6.68~133.6μg/mL范围内遵循比尔定律,回归方程为:A=0.0031ρ+0.023(ρ:μg/mL),检出限6.27μg/mL,表观摩尔吸光系数1.89×104L.mol-1.cm-1,相关系数为r=0.9970,并探讨了其反应机理。方法已用于尿样及生物样品中头孢哌酮含量的测定。     

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。     

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).     

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.     

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。     

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。     

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.     

Synthesis of Tyrosol and Hydroxytyrosol Glycofuranosides and Their Biochemical and Biological Activities in Cell-Free and Cellular Assays

Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.     

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.