水质毒性测定仪在水质急性毒性测定中的应用

目的 探讨TOXTRACER水质毒性测定仪在水质急性毒性测定中的应用。方法 采用荷兰生产的TOXTRACER水质毒性测定仪测定了不同条件下费氏弧菌(Vibrio fisheri)对HgCl2的抑制发光率,并对各种水样进行了抑制发光率和EC50值的测定。结果 0．20mg／L的HgCl2溶液在10、15、30min反应时间里的抑制发光率差异很小。0．10、0．20、0．40mg／L HgCl2溶液反应15min时的抑制发光率的变异系数分别为12．3％,2．6％,0．9％。在10—30min的反应时间里,HgCl2的浓度与其抑制发光率(％)之间线性关系均较好,EC50值(半数有效浓度)稳定。该仪器使用的费氏弧菌可连续使用约5h,它对HgCl2的敏感性优于国产冻干菌株(Photobacterium phosphoreum T3)。费氏弧菌的抑制发光率与0．2—40．0mg／L的As^2 ,0．5-5．0mg／L的Cr^3 ,0．05-0．40mg／L的Hg^2 呈线性关系。结论 该仪器可直接准确定量测定水质急性毒性。     

硫喷妥选择性电极的研究

In this paper, PVC membrane electrodes were prepared with thiopental-hexadecyltrioctylammonium iodide (HTOA) and thiopental-hexadecyltriphenylphosphonium iodide (HTPP) ion-pair associates as electroactive materials. The effects of the nature of associate counterion and its concentration in the membrane phase have been studied. The electrode based on thiopental-HTOA membrane shows Nernstian response range from 1 × 10^-1 to 1 × 10^-4M, with an average slope of 56.0 mV/pC. The limit of detection is 1.2 × 10^-5M. The potentiometric selectivity coefficients of various common inorganic and organic ions including those which are similar to thiopental in structure were determined. The 0.01 M NaOH is selected as measuring medium for potentiometric measurements. The electrode was used for determining the thiopental sodium content in some injection preparations. The method is quicker and simpler than the pharmacopeia procedure.     

硫喷妥选择性电极的研究

硫喷妥钠属巴比妥类药物,是一种常用静脉麻醉剂。中国药典采用萃取—重量法测定,操作繁杂费时。Cosofret等人曾报道采用液膜Ag~+离子选择性电极和固膜Ag~+离子选择性电极,AgNO_3作滴定剂,电位滴定法测定硫喷妥钠纯品的含量。但对含有Na_3CO_3的硫喷妥钠粉剂样品应用不便。我们研制成直接响应硫喷妥离子的PVC膜硫喷妥电极,对硫喷妥钠具有较好的响应特性,能满足硫喷妥针剂快速分析的需要。     

深圳市医院污水治理状况

为了解深圳市近两年来医院污水的治理情况 ,在２０００年９月至２００１年１２月间 ,对深圳市区１０家医院排放污水进行监测调查。每季度监测１次 ,共检验水样５７个 ,测定项目为余氯、粪大肠菌群。采样及分析方法按照《水和废水监测分析方法》第３版进行。评价标准按照ＧＢ８９７８＿１９９６二级标准 :余氯＞３ｍｇ／Ｌ、粪大肠菌群１０００个／Ｌ进行评价。监测结果见表１。从监测结果可以看出 :粪大肠菌群、余氯分别有超标及不合格现象。粪大肠菌群超标率在１０．０%～５０．０%之间 ,最高测定值为≥２．４×１０５ 个／Ｌ。余氯不合格…