新显色剂对——偶氮苯重氮氨基偶氮苯磺酸用于测定痕量镉研究

本文报告在PH10.0的NH_3·NH_4Cl体系和Triton x-100存在下,对—偶氮苯重氮氨基偶氮苯磺酸与镉形成红色络合物,最大吸收峰532mm,摩尔吸光系数2.02×10~5L·mol~(-1)·cm~(-1) ,并研究了测定镉的各种条件.     

废水和土壤样品中微量T1的原子吸收测定

本文研究了T1与Br或I的离子缔合物在不同的HC1或H_2SO_4介质中,用MIBK、环己酮、乙酸戊酯、乙酸丁酯和乙酸乙酯等有机溶剂的萃取效率,以及受酸度影响的情况,从而选择出最佳酸度、萃取剂和测定条件。本方法用于土壤及废水(天然水)中微量T1的测定,收到了良好的效果。     

真菌对微量元素铁、锌、硒生物富集作用的研究

研究了在不同培养基成分和同一培养基成分中 ,三株酵母菌和三株食用菌对Fe ,Zn ,Se的富集作用 .结果表明 :培养基成分、微量元素浓度和不同的菌株会影响六株真菌的生物富集作用 .提高培养基中蛋白质、脂肪和Fe ,Zn ,Se的浓度 ,有利于它们对Fe ,Zn ,Se的富集 ,较高浓度的Fe ,Zn ,Se盐能促进香菇菌丝的生长     

直接滴定法测定天然水体金属有机络合参数的动力学影响理论分析

对天然水体痕量金属有机络合参数直接滴定法测定的动力学影响进行了理论分析；导出了１：１络合滴定反应的动力学影响公式，并用计算机模拟计算了几种因素对滴定平衡时间的影响，获得满意结果。     

生活与工业污水混合处理系统中关键毒物追踪

以常州市城北污水处理厂的进水和A^2O出水为研究对象，采用毒性鉴别评价（T IE）程序，对关键毒物进行了追踪。结果表明，进水对大型蚤（Daphnia magna）具 有24h急性毒性，经过A^2O系统的处理，出水已不显示24h急性毒性；因曝气可去除废水毒性，C18固相提取亦可去除废水毒性，据此判断进水中存在的主要毒物 为挥发性非极性有机化合物。进出水的GC／MS图谱显示，处理前后有机物浓度大大降低，关键毒物基本去除。     

阻抑动力学光度法测定痕量锡

基于痕量锡在稀硫酸介质中对溴酸钾氧化酸性品红反应的抑制作用 ,建立了测定痕量锡的动力学光度法 ,检出限为 1 .6× 1 0 - 11/ g·m L- 1,测定范围为 0～ 0 .2 / μg· 2 5 m L- 1。用于天然水中痕量锡的测量。     

简述煤中微量元素的环境学研究进展

分析了煤中微量元素研究的意义和必要性,叙述了国内外对煤中微量元素研究的历史和现状,以及煤中微量元素的析出机理,提出煤中微量元素在生态环境中的迁移和环境效应是今后研究的主要方向。     

土壤里的微量元素与土壤肥力变异因子关系分析

运用主成分分析选取土壤肥力变异因子。三个主成分的累积贡献率达85．21％，分别命名为：有机质因子、酸碱度因子、质地因子。将各样品的主成分因子得分作为自变量．土壤微量元素含量作为因变量，进行逐步回归分析，得到回归方程。根据方程的回归系数大小可以评价各肥力变异因子对土壤微量元素累积和迁移的作用大小。     

Soil emissions of NO, N2O and CO2 from croplands in the savanna region of central Brazil

In the last 40 years, a large area of savanna vegetation in Central Brazil (Cerrado) has been converted to agriculture, with intensive use of fertilizers, irrigation and management practices. Currently, the Cerrado is the main region for beef and grain production in Brazil. However, the consequences of these agricultural practices on NO, N₂O and CO₂ emissions from soil to atmosphere are still poorly investigated. The objectives of this study were to quantify soil emissions of NO-N, N₂O-N and CO₂-C in different no-till cultivation systems in comparison with native savanna vegetation. The agricultural areas included: (a) the maize and Brachiaria ruzizienses intercropping system followed by irrigated bean in rotation; (b) soybean followed by natural fallow; and (c) cotton planting over B. ruzizienses straw. The study was performed from August 2003 to October 2005 and fluxes were measured before and after planting, after fertilizations, during the growing season, before and after harvesting. NO-N fluxes in the soybean field were similar to those measured in the native vegetation. In the cornfield, higher NO-N fluxes were measured before planting than after planting and pulses were observed after broadcast fertilizations. During Brachiaria cultivation NO-N fluxes were lower than in native vegetation. In the irrigated area (bean cultivation), NO-N fluxes were also significantly higher after broadcast fertilizations. Most of the soil N₂O-N fluxes measured under cultivated and native vegetation were very low (<0.6 ng N₂O-N cm⁻² h⁻¹) except during bean cultivation when N₂O-N fluxes increased after the first and second broadcast fertilization with irrigation and during nodule senescence in the soybean field. Soil respiration values from the soybean field were similar to those in native vegetation. The CO₂-C fluxes during cultivation of maize and irrigated bean were twice as high as in the native vegetation. During bean cultivation with irrigation, an increase in CO₂-C fluxes was observed after broadcast fertilization followed by a decrease after the harvest. Significantly lower soil C stocks (0-30 cm depth) were determined under no-tillage agricultural systems in comparison with the stocks under savanna vegetation. Fertilizer-induced emission factors of N oxides calculated from the data were lower than those indicated by the IPCC as default.     

Evaluation of the levels and sources of trace elements in urban particulate matter

An assessment of air quality of Belgrade, Serbia, was performed by determining the trace element content in airborne daily PM₁₀ and PM_2.5 samples collected from a central urban area. The ambient concentrations of Zn were the highest in PM_2.5 (1,998.0 ng m⁻³). Multivariate receptor modelling (principal component analysis and cluster analysis) has been applied to determine the contribution of different sources of specific metallic components in airborne particles. The obtained results showed that vehicle traffic and fossil fuel combustion in stationary objects were the main sources of trace metals in Belgrade urban aerosols.