二乙基二硫代氨基甲酸钠分光光度法测定铜的简便快速方法的探讨

水中可溶性铜和总铜的测定,有条件的实验室都使用原子吸收法测定,但对于一般的企业的污水处理部门,按照国家环境保护标准《水质铜的测定二乙基二硫代氨基甲酸钠分光光度法》(HJ 485—2009),使用分光光度计进行分析,也可满足要求。该方法原理是在氨性溶液中(pH=8～10),铜与二乙基二硫代氨基甲酸钠作用生成黄棕色络合物,络合物用四氯化碳或三氯甲烷萃取,在440nm波长处测量吸光度。本文对该方法进行探讨,采用缩少采样量和试剂用量(为原来的十分一),采用具塞的密闭比色管代替分液漏洞,减少工作强度和四氯化碳用量,与原方法相比更具经济性和更绿色环保。     

Electropolymerized poly（Toluidine Blue）-modified carbon felt for highly sensitive amperometric determination of NADH in flow injection analysis

Poly(pheniothiazine) films were prepared on a porous carbon felt (CF) electrode surface by an electrooxidative polymerization of three phenothiazine derivatives (i.e.,Tthionine (TN), Toluidine Blue (TB) and Methylene Blue (MB)) from 0.1 mol/L phosphate buffer solution (pH 7.0). Among the three phenothiazies, the poly(TB) film-modified CF exhibited an excellent electrocatalytic activity for the oxidation of nicotinamide adenine dinucleotide reduced form (NADH) at +0.2 V vs. Ag/AgCl. The poly(TB) film-modified CF was successfully used as working electrode unit of highly sensitive amperometric flow-through detector for NADH. The peak currents (peak heights) were almost unchanged, irrespective of a carrier flow rate ranging from 2.0 to 4.1 mL/min, resulting in the measurement of NADH (ca. 30 samples/hr) at 4.1 mL/min. The peak current responses of NADH showed linear relationship over the concentration range from 1 to 30 mol/L (sensitivity: 0.318 A/( mol/L); correlation coefficient: 0.997). The lower detection limit was found to be 0.3 mol/L (S/N = 3).     

Effects of UV/Ag-TiO2/O3 advanced oxidation on unicellular green alga Dunaliella salina: Implications for removal of invasive species from ballast water

The UV/Ag-TiO2/O3 process was investigated for ballast water treatment using Dunaliella salina as an indicator. Inactivation curves were obtained, and the toxicity of e uent was determined. Compared with individual unit processes using ozone or UV/Ag-TiO2, the inactivation e ciency of D. salina by the combined UV/Ag-TiO2/O3 process was enhanced. The presence of ozone caused an immediate decrease in chlorophyll a (chl-a) concentration. Inactivation e ciency and chl-a removal e ciency were positively correlated with ozone dose and ultraviolet intensity. The initial total residual oxidant (TRO) concentration of e uent increased with increasing ozone dose, and persistence of TRO resulted in an extended period of toxicity. The results suggest that UV/Ag-TiO2/O3 has potential for ballast water treatment.     

光催化反应器中臭氧产量及其影响因素研究

二氧化钛光催化降解染料废水具有反应迅速、降解彻底的优点.文章以悬浮态TiO2作为自制紫外光催化反应器(145W,185W)的催化剂,处理通有定量夺气的清水来产生微量的臭氧,通过改变臭氧捕捉方式、初始pH值、反应时间、TiO2用量及光照强度,研究纯水中臭氧产量及pH与上述因素之间的关系,并以循环伏安法作为对照.单因素实验...     

气相色谱法测定氯雷他定原料的残留溶剂

用毛细管柱气相色谱法建立氯雷他定残留溶剂（甲苯、乙腈）的测定方法。结果表明：本测定法方法简单、结果准确、重现性好,可用于氯雷他定原料中甲苯、乙腈2种残留溶剂的同时测定。     

COD测定中氯离子干扰消除方法的探讨

通过对银盐抑制法、Cl2校正法、标准曲线法、密封消解法、干扰扣除法、HCl去除法6种方法进行试验对比,分析COD测定中可靠、无毒、适用的消除氯离子干扰的方法,并分析了这些方法的特点和可行性。     

菜地氨挥发损失及影响因素原位研究

为获得菜地氨挥发通量和氨挥发损失率,并探讨其与环境影响因素之间的关系,于2009年1月～2009年5月,采用由风洞系统-大气气态污染物连续收集与在线分析装置和离子色谱联用组成的、时间分辨率为15min的氨挥发在线测定系统,用模拟试验方法对菜地(蔬菜上海青和生菜)施用尿素氨挥发特征进行研究.结果表明,系统氨气收集效率为(...     

紫外分光光度法与TOC/TN分析仪测定水中总氮的对比分析

摘要：总氮含量超标是导致水体富营养化的主要原因之一,因此需准确测定水体中总氮的含量。文章对TOC／TN分析仪测定地表水和国家环境部标准样品中的总氮含量和碱性过硫酸钾氧化一紫外分光光度计法测定结果进行了对比实验和实验数据分析,实验结果表明,两者方法结果一致性良好,测定结果准确可靠,TOC／TN分析法为快速准确测定总氮提供新的方法。     

重铬酸钾用量对硫铬氧化法测定土壤有机碳的影响

硫铬氧化法是在恒温加热条件下（135±2℃）,浓H2SO4介质中,用K2Cr2O7氧化土壤中的有机碳,通过分光光度法测定被还原的三价铬（Cr3＋）含量来计算出土壤有机碳的含量。实验发现适当增加重铬酸钾的用量可提高分析方法的测定上限,更好适应土壤有机碳的测定。     

快速消解分光光度法测定化学需氧量

采用快速消解分光光度法测定水样中的COD,操作简单、测定快速、结果准确.与经典的重铬酸盐法相比,测定结果具有较好的比对性;试验过程试剂用量小,减少了银盐、汞盐、铬盐带来的二次污染问题;消解过程短,能有效降低能耗.