溴化十六烷基吡啶存在下硫酸铵—碘化钾—结晶紫体系浮选分离铋(Ⅲ)的研究

研究了溴化十六烷基吡啶存在下硫酸铵—碘化钾—结晶紫体系浮选分离铋的行为及其与常见离子分离的条件.结果表明,在O.5mL溴化十六烷基吡啶(10g/L)存在下,当固体(NH_4)_2SO_4、碘化钾溶液(0.1mol/L)和结晶紫溶液(0.001mol/L)的用量分别为1.0g、1.0mL、1. 0mL时,控制pH值为7.0,Bi~(3+)可被该体系浮选,而常见离子Zn~(2+)、Fe~(2+)、Co~(2+)、Ni~(2+)、Al~(3+)不被浮选,据此实现了Bi~(3+)与这些离子的定量分离,对合成水样进行了定量浮选分离测定,结果满意。     

流动注射化学发光法测定芦丁

提出使用芦丁增强KMnO4-NaOH化学发光体系,结合流动注射分析技术进行芦丁的测定.本法选择性好、灵敏度高.芦丁在1 0×10-7～5 0×10-5g/mL浓度范围内与化学发光分析信号呈线性关系;检出限为7×10-8g/mL;对5 0×10-6g/mL的芦丁进行11次连续测定,相对标准偏差为2 5%.方法已成功地应用于片剂中芦丁含量的测定.     

线粒体ATP敏感性钾通道在心肌缺血保护中的作用

缺血预处理是指心肌反复多次短暂缺血/再灌注,对随后长时间心肌缺血/再灌注的一种保护.缺血预处理对心肌的保护机制十分复杂,一般公认为线粒体ATP敏感性钾通道(mitoKATP)是心肌缺血预处理保护机制的终末效应器之一.mitoKATP开放后可通过以下3条途径对抗心肌缺血损伤:减少线粒体膜Ca2 通道对Ca2 内流的驱动力,抑制Ca2 内流,减轻心肌细胞钙超载;保护线粒体呼吸链,减轻自由基释放引起的损伤;抑制线粒体转换孔开放,防止细胞色素C从线粒体释放,减少细胞凋亡.     

Cell-like-carbon-micro-spheres for robust potassium anode

Large-scale low-cost synthesis methods for potassium ion battery (PIB) anodes with long cycle life and high capacity have remained challenging. Here, inspired by the structure of a biological cell, biomimetic carbon cells (BCCs) were synthesized and used as PIB anodes. The protruding carbon nanotubes across the BCC wall mimicked the ion-transporting channels present in the cell membrane, and enhanced the rate performance of PIBs. In addition, the robust carbon shell of the BCC could protect its overall structure, and the open space inside the BCC could accommodate the volume changes caused by K⁺ insertion, which greatly improved the stability of PIBs. For the first time, a stable solid electrolyte interphase layer is formed on the surface of amorphous carbon. Collectively, the unique structural characteristics of the BCCs resulted in PIBs that showed a high reversible capacity (302 mAh g⁻¹ at 100 mA g⁻¹ and 248 mAh g⁻¹ at 500 mA g⁻¹), excellent cycle stability (reversible capacity of 226 mAh g⁻¹ after 2100 cycles and a continuous running time of more than 15 months at a current density of 100 mA g⁻¹), and an excellent rate performance (160 mAh g⁻¹ at 1 A g⁻¹). This study represents a new strategy for boosting battery performance, and could pave the way for the next generation of battery-powered applications.     

溴甲酚绿-高碘酸钾催化光度法测定痕量Mn（Ⅱ）

研究了在pH 4.1HAc—NaAc介质中,以氨三乙酸为活化剂,Mn（Ⅱ）催化高碘酸钾氧化溴甲酚绿褪色反应的条件及影响因素,建立了动力学光度法测定痕量Mn（Ⅱ）的新方法。方法的线性范围为0.4～12μg/L;检出限为0.12μg/L,对8μg/L Mn（Ⅱ）平行测定11次的相对标准偏差为0.09%。该催化反应的表观活化能为42.24kJ/mol,反应的表观速率常数为3.5×10^-4 s^-1。该方法具有较高的灵敏度和选择性,用于井水、自来水样品中锰含量的测定,结果令人满意。     

采用铬酸钾-罗丹明B化学发光体系对安乃近进行定量测定

采用铬酸钾．罗丹明B化学发光体系对安乃近进行定量测定．在酸性溶液中,铬酸钾可以氧化安乃近并在荧光试剂罗丹明B存在的条件下,产生强烈的化学发光信号,根据光信号的大小可对安乃近的含量进行测定．其工作曲线的线性范围为O．03—15．0μg·mL^-1,检出限为0．01μg·mL^-1．该测定方法可用于片荆药物中安乃近的定量测定,结果令人满意．     

河水化学需氧量测定方法的对比

同时采用高锰酸钾法和重铬酸钾法测定河水水样的化学需氧量(COD),结果表明,用重铬酸钾法所测得的COD值较高,因此,不能把两种方法所测定的结果互相混用。     

氯酸钾催化热分解反应动力学研究

本文通过TG—DTG—DTA实验方法,对氯酸钾催化热分解反应动力学及其反应过程进行了研究,并与氯酸钾的非催化热分解反应比较,结果是:分解反应都是连续一次进行完毕;催化剂二氧化锰降低了反应的活化能,使反应起始温度下降,反应速度常数提高了三个数量级。对于可能的反应机理亦作了初步推断。     

A new electrochemical oscillatory system of bromate in alkaline solution

A new electrochemical oscillatory system of bromate in alkaline solution is reported.In Pt-Bromate-Alkaline solution system,two different types of electrochemical oscillations(Type Ⅰ and Type Ⅱ) can be observed.Type Ⅰ appears before hydrogen evolution and Type Ⅱ involves periodic hydrogen evolution.Type Ⅰ relates to the adsorption/desorption of the hydrogen on platinum electrode,and Type Ⅱ with periodic oscillation stems from the coupling of electrochemical reactions(the reduction of bromate and evolution hydrogen reaction) with mass transfer(diffusion and convection).More over,under the right conditions,the two types appear in different oscillatory modes,for example,simple periodical mode and mixed one,etc..Crossed cycle in the cyclic voltammograms,which is the basic characteristics for electrochemical oscillatory systems,has also been observed as expected.     

碘酸钾氧化合成3-碘对氨基苯磺酸的研究

以对氨基苯磺酸和碘化钾为原料,碘酸钾为氧化剂,合成了3-碘对氨基苯磺酸,并对影响合成3-碘对氨基苯磺酸的一系列因素进行了研究.研究结果表明,对氨基苯磺酸用量为0.008 mol,碘酸钾用量为1.05g,以30 mL水作为溶剂,加入4 mL醋酸,温度为70～80℃,反应4h,3-碘对氨基苯磺酸的产率可达到90.05％.