菌株NKS-3对溴氨酸脱色特性探讨

从受溴氨酸污染地筛选出菌株ＮＫＳ－ ３ ,它对溴氨酸有脱色作用。菌株生长随碳源浓度增加而旺盛,溴氨酸能刺激菌株生长。溴氨酸浓度即使达到１０００ ｍｇ／Ｌ 也能被菌株基本脱色。研究发现,盐度抑制菌生长,在含盐培养液中溴氨酸的脱色过程被抑制     

吉林省城市大气降水pH值时空分异及成因

通过对吉林省８个代表城市１９９２－１９９７年大气降水观测数据的统计分析,对大气降水ＰＨ值的时空分异进行了探讨。结果表明：吉林省中西部城市大气降水基本呈中性;东部的图们,珲春两市大气降水酸化亚得,多年平均降水ＰＨ分别为５．１２和５．３８;全省碱性降水多集中在吉林市。     

植物对酸沉降的净化缓冲作用研究综述

从植物对ＳＯ２的吸收作用、森林冠层对湿沉降的缓冲作用以及森林枯枝落叶层对酸沉降的吸收缓冲作用３个方面介绍了国内外在植物对酸沉降的净化缓冲作用方面的研究成果。     

A review of biomarker compounds as source indicators and tracers for air pollution

An overview of the application of organic geochemistry to the analysis of organic matter on aerosol particles is presented here. This organic matter is analyzed as solvent extractable bitumen/ lipids by gas chromatography-mass spectrometry. The organic geochemical approach assesses the origin, the environmental history and the nature of secondary products of organic matter by using the data derived from specific molecular analyses. Evaluations of production and fluxes, with cross-correlations can thus be made by the application of the same separation and analytical procedures to samples from point source emissions and the ambient atmosphere. This will be illustrated here with typical examples from the ambient atmosphere (aerosol particles) and from emissions of biomass burning (smoke). Organic matter in aerosols is derived from two major sources and is admixed depending on the geographic relief of the air shed. These sources are biogenic detritus (e.g., plant wax, microbes, etc.) and anthropogenic particle emissions (e.g., oils, soot, synthetics, etc.). Both biogenic detritus and some of the anthropogenic particle emissions contain organic materials which have unique and distinguishable compound distribution patterns (C₁₄-C₄₀). Microbial and vascular plant lipids are the dominant biogenic residues and petroleum hydrocarbons, with lesser amounts of the pyrogenic polynuclear aromatic hydrocarbons (PAH) and synthetics (e.g., chlorinated compounds), are the major anthropogenic residues. Biomass combustion is another important primary source of particles injected into the global atmosphere. It contributes many trace substances which are reactants in atmospheric chemistry and soot paniculate matter with adsorbed biomarker compounds, most of which are unknown chemical structures. The injection of natural product organic compounds into smoke occurs primarily by direct volatilization/steam stripping and by thermal alteration based on combustion temperature. Although the molecular composition of organic matter in smoke particles is highly variable, the molecular tracers are generally still source specific. Retene has been utilized as a tracer for conifer smoke in urban aerosols, but is not always detectable. Dehydroabietic acid is generally more concentrated in the atmosphere from the same emission sources. Degradation products from biopolymers (e.g., levoglucosan from cellulose) are also excellent tracers. An overview of the biomarker compositions of biomass smoke types is presented here. Defining additional tracers of thermally-altered and directly-emitted natural products in smoke aids the assessment of the organic matter type and input from biomass combustion to aerosols. The precursor to product approach of compound characterization by organic geochemistry can be applied successfully to provide tracers for studying the chemistry and dispersion of ambient aerosols and smoke plumes. Presented at the 6th FECS Conference on Chemistry and the Environment, Atmospheric Chemistry and Air Pollution, August 26–28, 1998, Copenhagen.     

光电协同催化氧化苯甲酸的试验研究

在自制的光电协同催化氧化反应器中,对苯甲酸溶液进行了光电协同催化氧化处理研究,考察了阳极偏电压、反应氛围和制备光阳极所用基材对苯甲酸降解效率的影响,并比较了光电协同催化氧化与光解、光催化氧化和电解处理对苯甲酸去除率的差异.试验结果表明,经过1h的处理,光电协同催化氧化对苯甲酸的去除率可达85%以上,远远高于光解、光催化氧化和电解处理对苯甲酸的去除率(依次为48%、30%和约0%),具有明显的光电协同作用;工作电极与对电极采用内外同心圆柱形的布置方式;在通入高纯氮的条件下,TiO₂/Ti板光阳极对苯甲酸的去除率在1h时可达98%,优于TiO₂/Al板光阳极在仆时对苯甲酸85%的去除率;在通入纯氧的条件下,TiO₂/Ti板光阳极和TiO₂/Al板光阳极经过1h对苯甲酸的去除率均接近100%.     

聚合氯化铁对浊度和腐殖酸的絮凝特性研究

采用聚合氯化铁(PFC)絮凝剂在不同pH条件下处理高岭土悬浮液和腐殖酸溶液, 测试了絮凝过程中的Zeta电位、浊度和腐殖酸的去除率变化.结果表明:pH=4时, PFC投加量最小, 剩余浊度最大,投加范围最窄;pH=7时次之;pH=10时由于Fe(Ⅲ)离子的正电荷减弱, 电中和能力不强, 而且同时产生Fe(OH)₃(s)的吸附作用使得剩余浊度最低, 投加范围最宽, 但投加量很大;在酸性条件下腐殖酸与Fe(Ⅲ)离子最容易发生络合反应;腐殖酸的存在并没有影响PFC的絮凝效果.     

苯甲酸生产废水的处理与资源化

为有效地回收甲苯液相氧化法生产苯甲酸的工业废水中的苯甲酸和乙酸,并配合废水生物降解的末端处理技术,研究了20%,30%和50%磷酸三丁酯(TBP)/煤油的混合溶剂、正辛醇和甲苯萃取苯甲酸稀溶液特性,以及对工业废水处理的实验.结果表明,TBP对苯甲酸稀溶液具有良好的萃取作用,而纯溶剂体系与溶剂的极性有关,正辛醇的萃取能力与30%TBP相当;残液中的COD_Cr值由萃取剂在水中的溶解和苯甲酸自身的COD_Cr值组成,其中残液中溶剂溶解导致的COD_Cr值随其中苯甲酸浓度变化不明显,且COD_Cr值的大小为:50%TBP≈30%TBP>正辛醇>20%TBP>甲苯.针对工业废水中主要含有苯甲酸和乙酸的工况,提出了废水资源化的处理工艺流程,即首先采用甲苯进行废水中苯甲酸的回收,之后,再利用三烷基氧磷/煤油为萃取剂回收废水中的醋酸,进一步生产绿色化学品乙酸钙镁盐.     

粉煤灰--Fenton法处理酸性红印染废水

以美尔雅酸性红废水为研究对象 ,采用粉煤灰—Fenton法进行处理研究。确定了絮凝剂及其最佳浓度、粉煤灰和Fenton试剂处理的最佳条件。经处理后废水COD的去除率达 97%以上 ,色度去除率达 99%以上。     

吸附树脂对苯甲酸的吸附动力学研究

对比超高交联吸附树脂NJ 8与AmberliteXAD 4对苯甲酸的静态吸附动力学性质 ,并深入讨论温度和起始浓度对平衡时间和吸附速率的影响。NJ 8和XAD 4两种树脂在吸附苯甲酸的过程中 ,膜扩散和颗粒内扩散均为主控步骤 ,但是前者颗粒内扩散占据优势 ,而后者膜扩散占据优势     

锡林郭勒盟植被物候枯黄期对干湿变化的时间多尺度响应

基于全球监测与建模组(GIMMS)1982～2015年第三代归一化植被指数(NDVI)GIMMS NDVI 3g数据集和气象观测数据,采用累计NDVI的Logistic曲线曲率极值法提取锡林郭勒草原植被枯黄期,并结合不同时间尺度标准化降水蒸散指数(SPEI)分析植被枯黄期对干湿变化的响应特征.结果表明:1982～201...