鄱阳湖典型区域重金属污染的水生植物监测与评价

对不同水期鄱阳湖饶河入湖段不同区域的水生植物进行了重金属元素Cu,Zn,Pb和Cd等的污染调查与室内监测分析,结果表明:水生植物对重金属元素的吸收与积累反映了环境中的重金属污染水平,不同水生植物对各种重金属元素的吸收富集状况具有相对一致性,即Zn>Cu>Pb>Cd;对各种水生植物在不同时期的重金属综合污染指数(MPI)评价结果表明:多数水生植物的重金属综合污染指数以枯水期高于丰水期为主;大部分水生植物根部的重金属含量比茎、叶等部分偏高,反映了重金属元素在植物不同部位细胞体内的迁移特性。     

TRPO 萃取-固体荧光法测定土壤和空气尘埃中的铀

本文介绍了用 TRPO 萃取-固体荧光法测定土壤和空气尘埃中铀的方法。用混合铵盐和硫酸-硝酸分别预处理土壤和空气尘埃样品,在硝酸体系中用30%TRPO 的 OK 溶液萃取铀,制备 NaF 熔珠,测定铀含量。实验结果表明,本方法对土壤和空气尘埃样品中铀的全程回收率分别为(89.6±11.8)%和(85.5±5.6)%,灵敏度分别为0.03μg/g 和0.2pg/L。     

稀土铁矿尘中钍含量的测定

本文报道了一种稀土铁矿尘样品中钍含量的测定方法。用 CL-TBP 萃淋树脂和743阳离子交换树脂分离、纯化钍,电沉积制源,然后进行α谱测量。本方法的全程回收率为94.3±3.2%,对铀和其他α核素具有较好的分离效果,方法的精密度和准确度较好。用本方法测定了部分稀土铁矿尘样品中钍的含量。     

管线钢奥氏体晶界的浸蚀及测定

介绍一种显示管线钢奥氏体晶界的浸蚀剂及奥氏体晶粒平均尺寸的测定方法。结果表明，此浸蚀剂是管线钢一种理想的奥氏体晶界浸蚀剂，所采用的测定方法的精确度较高。     

Voltammetric studies of a novel bicopper complex modified glassy carbon electrode for the simultaneous determination of dopamine and ascorbic acid

A novel modified glassy carbon electrode (GCE) with a binuclear copper complex was fabricated using a cyclic voltammetric method in phosphate buffer solution. This modified electrode shows very efficient electrocatalytic activity for anodic oxidation of both dopamine (DA) and ascorbic acid (AA) via substantial decrease in anodic overpotentials for both compounds. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) using this modified electrode show two well-resolved anodic waves for the oxidation of DA and AA in mixed solution, which makes it possible for simultaneous determination of both compounds. Linear analytical curves were obtained in the ranges 2.0–120.0 μM and 5.0–160.0 μM for DA and AA concentrations by using DPV methods, respectively. The detection limits were 1.4 × 10⁻⁶ M of DA and 2.8 × 10⁻⁶ M of AA. This electrode was used for AA and DA determinations in medicine and foodstuff samples with satisfactory results.     

抑制型电导检测饮用水中草甘膦的研究

建立了一种抑制型电导检测饮用水中草甘膦的检测方法。使用IonPac19柱,氢氧化钾溶液等度淋洗,用抑制型电导检测器直接分析。实验结果表明,本方法线性范围广,在0～2mg/L范围内相关性好(r0.9990);精密度和准确度高,样品加标回收率在89.3%～92.4%之间,样品测定的相对标准偏差为2.5%;方法灵敏度高,25μL进样时,定量检出限达50μg/L;测定受其他阴、阳离子及酸碱度条件等影响较小。本方法完全可以满足国家饮用水卫生标准的检测要求,且具有灵敏度高,准确度好,受干扰小,操作简单的特点。     

Removal, preconcentration and determination of trace heavy metal ions in water samples by AAS via chemically modified silica gel N-(1-carboxy-6-hydroxy) benzylidenepropylamine ion exchanger

The use of chemically modified silica gel N-(1-carboxy-6-hydroxy) benzylidenepropylamine (SiG-CHBPA), ion exchanger for removal and preconcentration of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb in natural water samples collected from River Nile, Mediterranean Sea and other locations followed by their consecutive AAS determination was described. The effects on the percentage of recovered metal ions including mass change of ion exchanger, stirring time, pH of sample solutions and eluent concentration were studied. The distribution coefficient K_d, ml g^− 1 and the percentage concentration of the studied metal ions on the ion exchanger at equilibrium, C_M,_eqm ,% (Recovery, %) were studied as a function of experimental parameters. The logarithmic values of the distribution coefficients, log K_d are 3-6.3. The interfering effects of some foreign ions on the removal, preconcentration and determination of the investigated metal ions were described. The metal-chelates formed between the ion exchanger and the studied metal ions were characterized by IR (absorption and reflectance), UV spectrometry, potentiometric titration and thermal analysis (TG and DTG). The reliability of the present method was confirmed by the comparison with a standard solvent extraction method. The present method is simple and rapidly applicable for the determination of the studied metal ions, ng ml^− 1 in different natural water samples.     

对苯二甲酸残渣中总酸含量的测定

通过实验改进并总结了氧化残渣系统浆料总酸含量的测定方法,提出在滴定前加入吡啶作溶剂,EDTA作掩蔽剂,有效改善了滴定速度慢、终点判定不准的情况,成功实现了残渣系统浆料总酸含量的准确测定。     

大型园区电气设计探讨

阐述大型园区电气设计的要点,包括电源要求、变电所设置、变压器容量的确定,以及牵头设计单位与其他合作单位的设计协调等,并简介某高校大型园区电气设计。     

腺苷蛋氨酸发酵液中甲醇含量测定方法研究

利用变色酸比色法和气相色谱法分别对甲醇诱导毕赤酵母基因工程菌发酵液中甲醇含量测定方法进行了研究。结果表明,变色酸比色法测定发酵液中甲醇浓度具有较好的精密度和准确度,与气相色谱法相比误差不大。因此,利用变色酸比色法测定腺苷蛋氨酸发酵液中甲醇浓度是一种简单、易行、准确的测定方法。