电化学现场时间分辩FTIR反射光谱和程序电位阶跃暂态响应信号同步检…

应用弛豫（或暂态）方法研究电极过程动力学始于五十年代，由于通过对暂态实验数据的解析能够获得反应速度常数、扩散系数、传统递系数、交换电流密度等参数，从而唯象地描述电化学反应动力学，这一研究领域至仍然十分活跃，从八十年代发展起来的电化学现场红外光为研究电化学应机理提供了分子水平上的数据，从而深化了对速度控制步骤等细节的认识，近几年来我们通过发展时间分辨电化学ＦＴＩＲ恍谱和程度阶跃技术成功地在分子水平上     

纳米多孔Pt,PtRu及PtRuIr催化剂的电化学FTIR光谱之比较(英文)

近年来,致力于Pt基电催化剂在燃料电池中的应用已取得显著成果.但随贵金属(如Pt)成本的增加,提高催化剂的活性以及降低负载量的需求也日益迫切.为此,作者合成并比较了纳米多孔Pt,PtRu及PtRuIr3种电催化剂.以扫描电镜(SEM)、能量色散谱(EDS)、X射线衍射(XRD)和X射线光电子能谱(XPS)表征水热法制得的纳米多孔电极.CO汽提实验和甲醇氧化反应测试上述纳米多孔材料的电催化活性.结果表明,添加Ir极大改善纳米多孔PtRu的活性.采用现场电化学FTIR光谱技术研究纳米多孔Pt,PtRu及PtRuIr电极上的甲醇氧化反应,以进一步揭示这种显著增强效应的成因.     

Sensor System for Simultaneous Measurement of Oxygen and Hydrogen Peroxide Concentration During Glucose Oxidase Activity

An amperometric sensor system, based on a repetitive double step potential method at a glassy carbon electrode, has been developed for the simultaneous measurement of hydrogen peroxide and oxygen concentrations. The current measured at a potential of –1 V (vs. Ag/AgCl/saturated Cl^–) corresponds to the sum of the reduction currents of hydrogen peroxide and dissolved oxygen. The current measured at –0.55 V (vs. Ag/AgCl/saturated Cl^–) is due to the reduction of dissolved oxygen to hydrogen peroxide. Alternatively, the concentration of dissolved oxygen can also be determined using a Clark electrode. The concentration of hydrogen peroxide and dissolved oxygen during enzymatic conversion of glucose can be followed on line and be used to control the process.     

双通道毛细管电泳-电化学法同时检测硝酸根、亚硝酸根和氯酚类化合物

双通道毛细管电泳-电化学法同时检测硝酸根、亚硝酸根和氯酚类化合物;双通道毛细管电泳电化学法;硝酸根;亚硝酸根;氯酚     

Nanohybrid Chemosensor for the Simultaneous Detection of Fluoride and Iodide in Aqueous System and Its Utility in Real Samples

A nanohybrid chemosensor for specific, selective and simultaneous recognition of iodide and fluoride was prepared through decoration of silver nanoparticles onto Schiff‐Base based organic nanoparticles. The developed chemosensor showed specific recognition ability for this analytes at low concentrations with detection limits at 690 nM for fluoride and 11 nM for iodide in two different regions of DPV profiles. Theoretical calculations based in Density Functional Theory were performed, which supports experimental results by demonstrating the binding selectivity of nanohybrids with I^? and F^?. The proposed sensor was also used for real sample analysis and results were verified using some standard literature method.     

Electrochemistry and Simultaneous Detection of Metabolites of Purine Nucleotide Based on Large Mesoporous Carbon Modified Electrode

A large mesoporous carbon modified glassy carbon electrode (LMC/GCE) was prepared. The morphology and structure of the LMC were characterized. The LMC/GCE was used to investigate the electrochemical behaviors of metabolites of purine nucleotide, uric acid (UA), xanthine (XA) and hypoxanthine (HX). The LMC/GCE exhibited high electrocatalytic activity towards the three compounds when compared with those obtained at the GCE. Furthermore, the LMC/GCE realized simultaneous determination of UA, XA and HX at a physiological pH of 7.0 with wide linear range and low detection limit. The electrocatalytic activity of the LMC/GCE towards guanine (G) and adenine (A) was also investigated.     

A Batch Injection Analysis System with Square-wave Voltammetric Detection for Fast and Simultaneous Determination of Zinc and Ascorbic Acid

The determination of organic and inorganic compounds in a single run is still a great challenge. In this paper, we developed a method for fast simultaneous determination of ascorbic acid (AA) and zinc ions (Zn) using batch injection analysis with detection by square-wave anodic stripping voltammetry (BIA-SWASV). Britton-Robinson (BR) buffer solution (pH=6.0) as the supporting electrolyte and boron doped diamond (BDD) as the working electrode. The method presented favorable analytical characteristics such as fast response (67 injections h⁻¹), low detection limits (0.2 and 5.4 μmol L⁻¹ for Zn ions and AA, respectively) and recovery values of 99±3%.     

中红外光纤技术用于口腔肿瘤在体原位检测的研究

肿瘤是严重威胁人类健康和生命的疾病,早期诊断和及时治疗是提高肿瘤病人存活率的重要因素,肿瘤的发生和发展一般可分为3个阶段：(1)基因突变;(2)生物分子组成和结构发生改变;(3)细胞和组织形态发生变化,目前常用的影像学方法只能检测较大的肿块,组织标本的病理诊断法需在     

拉曼光谱检测系统的搭建及在仪器分析基础实验教学中的应用*

报道了一种可由学生自行搭建的拉曼光谱检测系统,并设计了配套的实验内容,引入了前沿的表面增强拉曼光谱(SERS)技术,应用于牛奶中违法添加物三聚氰胺的检测。学生通过对仪器的组装和测试,可以更加深入地理解科学仪器的结构和工作原理,有助于提高学生的动手能力和创新思维。     

吸光光度多组分同时测定方法研究——MR和PLS法测定钴、镍、铜三组分混合体系

用偏最小二乘法(PLS)和多元线性回归法(MR)分别对钴、镍、铜三组分混合体系进行同时测定,证明PLS法对光谱重叠严重的体系较MR法有更好的预报准确性.着重讨论了校正集样品数n、波长数,和特征变量数d等测定参数对预报结果的影响.     

基于3D打印薄层池和流场形电极的镉离子流动检测系统

首次提出了流场形(FFS)电极的概念,并印制了FFS三电极体系.结合3D打印的薄层流通池(TLFC),采用方波溶出伏安法(SWSV),构建了镉离子(Cd2+)流动电化学检测系统.考察了电极形状、测量方式、流速、介质条件、富集时间等条件的影响.结果表明,此检测系统测量灵敏度高,重现性和稳定性好.在优化条件下,Cd2+浓度在2 ～ 100 μg/L范围内与溶出峰电流呈良好的线性关系,相关系数为0.997,检出限为0.5 μg/L.将本方法应用于环境水样和生物甲烷发酵液中痕量Cd2+的检测,结果与ICP-AES无显著性差异,加标回收率为90％ ～ 106％.