辅酶Ⅰ在Co／CFUE上的电化学行为及应用

辅酶I(NAD+)在0.005moL/LTris 0.01moL/LNaCl溶液(pH7.0)中,于钴离子注入修饰碳纤维电极上出现一个S形的还原波,半波电位为-1.45V(vs.SCE)。峰电流与NAD+的浓度在2.38×10-5～4.76×10-4mol/L(r=0 9992)和4.76×10-4～1.78×10-3mol/L(r=0.9982)之间成线性关系,检出限为1.19×10-5mol/L,回收率在96.7%～103.4%之间。用线性扫描、循环伏安法研究了钴离子注入修饰碳纤维电极上NAD+的电化学行为。电极反应机理为:NAD++e NAD·;NAD·+e+H+ NADH;2NAD·→NAD2。另外,钴离子注入修饰碳纤维电极对NAD+具有电催化作用。     

气相二茂铁双电荷离子的动能谱研究

The unimolecular charge separation reactions of the doubly charged ions FeC_(10)H_(10)~(2+)、FeC_(10)H_9~(2+)、FeC_(10)H_8~(2+) produced in the ion source by electron impact from ferrocene have been studied using Mass analyzed Ion Kinetic Energy Spectrometry (MIKES) technique. From the values of the kinetic energy releases (T), the intercharge distances (R) of the exploding doubly charged ions in their transition structures have been estimated and some structural informations about the transition states can be obtained. The collision induced reactions of the FeC_(10)H_(10)~(2+) ion with Ar have been studied using MIKES, we postulate a new type of continuing reaction which may be "collisional charge separation induced dissociation".     

脱色阴离子交换剂的再生研究

提出一种新的离子交换剂再生理论，即吸附物的脱附依靠离子交换和络合的协同效应完成．以二价钙离子为再生剂，对糖液脱色用的阴离子交换树脂和阴离子交换纤维进行再生，并与传统的碱性钠盐相比较，研究证明钙离子为再生剂的工艺，具有低成本、无污染的特点．     

简易型离子选择电极-流动注射分析仪的研制及卤水中氯、溴和碘的连续测定

本文设计研制了简单实用的流通池,组装了简易型离子选择电极—流动注射分析仪,对体系的分析特点和影响因素进行了考察。此装置性能可靠,能满足简单流注分析的需要,并建立了卤水中Cl~-、Br~-和I~-的连续测定方法。     

Effect of ion pairing on steady-state voltammetric limiting currents at microelectrodes Part I. Theoretical principles

Voltammetric studies in solutions of high resistivity are facilitated by the use of microelectrodes under steady-state conditions. Such solutions are encountered with solvents of low permittivity because of the very sparing solubility of electrolytes. Moreover, in such media the supporting electrolyte, as well as the electroactive ionic species, is usually extensively ion paired. Here we predict the limiting current that will flow in these circumstances, when a monovalent ion undergoes a one-electron transfer at a hemispherical microelectrode to form a neutral product. The ion pairing equilibria are assumed to be fast but all diffusion coefficients are treated as distinct. An analytical solution is elusive in the general case, but a simple numerical procedure allows the limiting current to be predicted for any combination of the system parameters. Several special cases are also discussed, some of which yield explicit formulae for the limiting current. In a companion paper, experimental data are compared with the theoretical predictions.     

离子注入修饰电极检测硝基苯

离子注入是一种新技术，可按人们的意愿和需要，将不同的离子注入不同的基本电极表面，制成具有催化活性强，稳定性高，重现性好等特点的修饰电极。作者研究了离子注入钴和注入镍的玻碳电极在０．１ｍｏｌ／ＬＨＡｃ－ＮａＡｃ缓冲溶液中硝基苯的行为及测定。     

金属有机化合物的分析（Ⅷ）：氢硼酸金属有机络合物的反相色谱机理

本文研究了具有特殊结构的氢硼酸金属有机络合物的反相色谱及机理。在MicropakC_(18)柱上,加入含离子试剂的甲醇-水作为流动相,通过用电导法测定流动相电性能,Break-through法测定离子试剂在固定相上的吸附量及制备色谱法研究各流分组成,认为此类化合物的保留机理为动态离子交换过程。     

Ion mobility–mass spectrometry: a new paradigm for proteomics

Matrix-assisted laser desorption/ionization (MALDI) coupled with ion mobility–mass spectrometry (IM–MS) provides a rapid (μs–ms) means for the two-dimensional (2D) separation of complex biological samples (e.g., peptides, oligonucleotides, glycoconjugates, lipids, etc.), elucidation of solvent-free secondary structural elements (e.g., helices, β-hairpins, random coils, etc.), rapid identification of post-translational modifications (e.g., phosphorylation, glycosylation, etc.) or ligation of small molecules, and simultaneous and comprehensive sequencing information of biopolymers. In IM–MS, protein-identification information is complemented by structural characterization data, which is difficult to obtain using conventional proteomic techniques. New avenues for enhancing the figures of merit (e.g., sensitivity, limits of detection, dynamic range, and analyte selectivity) and optimizing IM–MS experimental parameters are described in the context of deriving new information at the forefront of proteomics research.     

离子交换-原子捕集-火焰原子吸收光谱法测定水中的超痕量镍

在文中所述条件下,镍的原子捕集灵敏度较常规法高320倍,即在离子交换法浓缩仅40倍的情况下,可使镍的测定灵敏度提高12800倍,从而成功实现了ppt级超痕量镍的测定。     

反相离子对高效液相色谱法测定蔬菜中多菌灵残留量

建立了一种用HPLC测定蔬菜中多菌灵残留量的分析方法。样品中多菌灵经甲醇提取,在pH 1~2时用二氯甲烷液液净化,水相调至弱碱性,再用二氯甲烷提取,提取液经浓缩,癸烷磺酸钠离子对试剂处理后,用HPLC-DAD分离测定,外标法定量。对于50 g样品,定容至10 mL,进样量20μL,检出限为0.05mg/kg,样品回收率>80%,RSD<10%,能满足农药残留分析的要求。