大气有机物GC分析预处理中的组分损失

大气有机物在脱水，富集过程中的组分损失造成ＧＣ分析的系统误差。回收率测定表明，在本实验条件下，疏水性有机组分在填充碱石棉与碳酸钾的脱水预柱上的损失率分别为２５％和１５％左右，亲水性的乙醇的损失经高达６０％左右。     

鲤鱼对三种硝基芳族化合物的摄取、释放和生物富集

用第二松花江水和鱼体中多次检出的三种硝基芳族化合物来分别测定鲤鱼体中的生物富集系数（ＢＣＦ），摄取和释放动力学参数，以及在肌肉、肠、肝和鳃等组织中的分布。试验在半静态条件下进行。硝基芳族化合物在鲤鱼体内的释放可用双区一级动力学模型很好地描述。鲤鱼对２，４－二硝基甲苯和对硝基氯苯的富集过程中发现有未知的代谢产物生成。     

陆地生物配体模型（t-BLM）初探：镁离子降低铜离子对小麦根的毒性

生物配体模型(BLM)同时考虑了水中金属离子的化学形态以及阳离子与金属离子在生物配体(BL)上的竞争对其毒性的影响,能成功预测水体金属的生物毒性/有效性.最近,BLM呈现出向土壤环境中拓展的趋势,发展能预测重金属对土壤生物毒性的陆地生物配体模型(t-BLM)正成为最新的国际研究热点.论文模拟土壤溶液,以土壤溶液中的主要阳离子Mg2+为例,通过单因素浓度控制-恒pH营养液培养-陆生植物根伸长抑制试验,定量探讨了不同浓度Mg2+存在下,铜离子(Cu2+)对小麦(Triticum aestivum)根的毒性.结果表明,Mg2+浓度升高显著减弱了Cu2+对小麦根的毒性,即呈现出保护效应.证实陆地生态系统中也存在阳离子对重金属植物毒性的保护效应,支持了BLM中阳离子和重金属离子在生物配体上存在竞争结合的假设,即BLM概念适用于陆生植物.定量分析表明,小麦根生长抑制的毒性效应指标EC50(以自由铜离子活度表示)与自由镁离子活度间存在良好的相关性,线性回归方程为:pEC50(Cu2+)=-0.36(Mg2+)+6.47(r2=0.9976),Mg2+对Cu2+毒性的影响强度可以通过该方程进行预测.论文积累了重金属铜对典型陆生受试植物小麦的毒性数据,探讨了t-BLM的构建方法学,并为其发展提供了思路.联合了土壤理化性质、金属形态及生物积累和毒性效应的t-BLM,将提供一个环境风险评价和制定土壤质量标准的新工具.     

气相色谱法估算多环芳烃的辛醇/水分配系数

通过对2－6环多环芳烃（PAHs)气相色谱保留时间（RGC）与HPLC保留值及与辛醇／水分配系数（KOW）对应关系的研究，发现RGC与HPLC保留值主KOW间存在明显的线性相关关系，建立了RGC与KOW间的一元回归方程，并对包括EPA16种优先控制的PAHs在内的33种多环芳烃化合物的KOW值进行估算，估算值的相对误差为0．10％－12．10％，平均值为4．51％。     

聚合物涂层纤维材料为固定相填充毛细管气相色谱及其在样品预处理中的应用

1　IntroductionGaschromatography(GC)isoneofthemostpopularseparationmethodsfortheanalysisofvolatilecompounds,andawidevarietyofpolymericmaterialsasthestationaryphases,havebeendeveloped .Incontrasttothesuccessfulapplicationsandsubsequentcommercializationofth…     

Concentration Evolution of Gas Species within a Collapsing Bubble in a Liquid Medium

In this study numerical methods are used to investigate the relationship between chemical concentration of gas species within a cavitating bubble, equilibrium radius of the gas bubble and pressure variations in the ambient liquid. For this purpose, governing equations are developed to describe the dynamic equilibrium of a bubble in a flowing fluid and mass transfer between gas and liquid phases, where it was assumed that gases undergo isothermal compression, obey the ideal gas law, Henry law. It is further assumed that the concentration of each phase within the bubble is uniform. The resulting nonlinear equations are solved using implicit Trapezoidal method with Newton iteration. Four gas species are modeled under various initial and ambient pressure variation conditions. These conditions maybe considered to represent typical cavitation events. The numerical results obtained are presented in terms of dimensionless numbers. These results indicate that chemical damage maybe an important component of cavitation surface damage, since high concentration profiles may develop within a collapsing bubble. Proposed formulation and numerical solutions are simple and cost effective to implement. The results presented in this study maybe used to benchmark experimental investigations or other more complex solutions, which are outside the scope of this study.     

Bioaccessibility of arsenic in soils developed over Jurassic ironstones in eastern England

Jurassic ironstones outcropping over parts of eastern England give rise to soils with arsenic concentrations in excess of the UK soil guideline value of 20 mg kg⁻¹ for residential areas. Total arsenic concentrations were determined for 73 ironstone derived soils and bioaccessible arsenic determined using an in vitro physiologically based extraction test. The bioaccessible arsenic concentration for these soils was found to be well below the soil guideline value with a mean concentration of 4 mg kg⁻¹ and a range of 2–17 mg kg⁻¹. The bioaccessible fraction ranges from 1.2 to 33%. Data from a sequential extraction test based on the use of aqua regia as the main extractant is presented for a subset of 20 of the soils. Chemometric data reduction is used to demonstrate that the bioaccessible arsenic is mainly contained within calcium iron carbonate (sideritic) assemblages and only partially iron aluminosilicates, probably berthierine, and iron oxyhydroxide phases, probably goethite. It is suggested that the bulk of the non-bioaccessible arsenic is bound up with less reactive iron oxide phases.     

碱性印染废水用于燃煤锅炉烟气脱硫除尘技术

介绍了当前国内利用碱性印染废水进行燃煤锅炉烟气湿法脱硫除尘的技术,并对其进行了技术经济分析。     

气相色谱法测定大气中烯烃的研究

采用硅胶－ＡｇＮＯ３富集样品,热解吸进样,气相色谱法分析大气中的烃一,富集过程在常温下进行。当富集样品０．１Ｌ时,乙烯,丙烯,丁二烯的最小检有度分别为０．０００６ｍｇ／ｍ＾３,０．００１ｍｇ／ｍ＾３、０．００４ｍｇ／ｍ＾３,相对标准偏差小于６％,加标回收率９７％－１０９％。     

高温煤气脱硫剂研究进展

系统地介绍了国外高温煤气脱硫剂的研究开发现状,指出我国重点研究开发铁系、锰系、锌系、铜系和钙系脱硫剂。