固相微萃取-气相色谱法联用测定水中氯苯系化合物

采用顶空固相微萃取与气相色谱联用技术对水中九种氯苯进行测定。优化了SPME的萃取条件,选用65μmPDMS—DVB萃取涂层,在加入1．5gNaCl,温度为20℃的条件下萃取15min,280％解吸4min。该方法的相对标准偏差小于8％,相关系数大于0．9988。将该方法应用于湘江水中氯苯的测定,回收率分别为79．4％-99．9％,证明了访方法对痕量氯苯分析的可行性与可靠性。     

Phosphorus fractionation in different trophic sediments of lakes from different regions, China

The characteristics of organic phosphorus (P(o)) fractions in the sediments of nine lakes from the middle and lower reaches of the Yangtze River region, Yungui Plateau, Qinghai-Tibet Plateau, Northeast China Region, and Mongolia-Xinjiang Plateau, China were investigated and the differences of the different lakes on P fractionation was discussed. The results indicated that organic matter (OM) showed significant positive correlations with P(o) in sediment samples, and the rank order of the P(o) fractions was: residual P(o) > HCl-P(o) > fulvic acid-P(o) > humic acid-P(o) > NaHCO(3)-P(o) with mean relative proportions 7.4 : 3.4 : 2.4 : 1.7 : 1.0. The labile and moderately labile P(o) were the main fractions in the sediments for shallow eutrophic lakes except for Lake Qilu, however, nonlabile P(o) was dominant in the sediments from deep lakes. Labile P(o) was significantly correlated with total phosphorus (TP), inorganic phosphorus (P(i)), P(o), NaHCO(3)-P(i), HCl-P(i) and NaOH-P(i), and the nonlabile P(o) was significantly and positively related to OM, TP, P(o) and NaOH-P(i).     

A 100 year sedimentary record of heavy metal pollution in a shallow eutrophic lake, Lake Chaohu, China

This study has worked on the evaluation of the temporal and spatial evolution of heavy metal contamination in sediment taken from a shallow eutrophic lake, Lake Chaohu, China, over the last 100 years, and thereby used (137)Cs and (210)Pb dating, a PIRLA procedure, statistical analysis, geochemical normalization and a enrichment factor calculation (EF). Concentrations of 5174, 29?325, 10.7, 36.4, 20.4, 386.0, 21.1 and 38.4 mg kg(-1) for Ti, Fe, Co, Cr, Cu, Mn, Pb and Zn, respectively, are proposed as natural background values for the Lake Chaohu based on a PIRLA procedure. The contamination history from the last 100 years can be divided into two periods. Before the 1960s, heavy metal contamination did not occur and there was no spatial difference for heavy metal distribution. Since the 1960s, heavy metal enrichment and contamination has occurred, and the west half of the lake region showed a higher degree of contamination than the east half to various intensified anthropogenic activities. In the east half of the lake region, the anthropogenic source of heavy metals mainly originated from agricultural intensification, whereas in the west half of the lake it originated from city runoff and industry as well as agriculture. In all anthropogenic heavy metals, Co is only from industry.     

回灌型准好氧填埋场脱氮特性及加速稳定化研究

采用2个模拟填埋生物反应器,1号柱渗滤液简单回灌,2号柱为渗滤液回灌准好氧联合运行方式,研究了渗滤液回灌准好氧生物反应器填埋场的脱氮特性及加速垃圾稳定化特性。研究结果表明：渗滤液回灌准好氧填埋场具有很强的脱氮能力,2号柱由厌氧运行方式改为准好氧条件下,渗滤液中的氨氮和凯式氮浓度分别由最大值的3198mg／L和3345mg／L降低到第160d的73mg／L和81mg／L,去除率分别为97．7％和97．6％,pH快速升高到8．0左右,COD浓度快速降低。渗滤液中溶解性有机物（DOM）分级结果表明,2号柱HA和FA含量的增加明显快于1号柱。2号柱DOM的三维荧光光谱特性发生了较大变化,荧光基团从60d结构简单的类蛋白物质转变为95d结构复杂的类胡敏酸和富里酸物质,而1号柱渗滤液DOM荧光基团一直是结构简单的类蛋白物质。结果表明回灌准好氧生物反应器填埋场的稳定化速度远快于简单回灌的生物反应器填埋场。     

中美中小学环境教育活动教学之比较

活动教学既是美国中小学环境教育的一大特色,也是美国实施环境教育的重要途径。中国中小学环境教育经过 20多年的探索和实践也逐渐形成了课堂教学与活动教学相结合、校内教育与校外教育相结合的环境教育方法。但两个国家的环境教育中的活动教学存在着许多不同之处。 活动教学的主要内容 　　笔者对美国中小学环境教育活动教学案例的主题分析发现：其中 29.1％的是关于动物的; 9.1％是关于植物的; 9.1％是关于自然生态环境的; 12.7％是关于固体废弃物的回 收循环利用; 14.54％是关于水问题的 (水污染问题和节约用水问题 ); 3.6％是有关…     

铁路建设项目环水保管理理论与实践

从环水保法律法规及专业技术、铁路建设项目管理理论、铁路工程建造技术和智能化信息化管理等方面阐述铁路建设项目环水保管理体系要素,提出包括目标体系、标准体系、支撑体系、保障体系4个部分的铁路建设项目环水保管理体系框架.从依法合规进行建设、总结形成标准体系、强化专项保护措施及开发信息管理系统等方面对铁路建设管理工作实践进行总...     

超临界二氧化碳萃取环境样品中金属离子的研究进展

原位络合的超临界萃取技术开辟了超临界二氧化碳（ＳＣ－ＣＯ２）萃取金属离子的新途径。本文综述国外有关ＳＣ－ＣＯ２萃取环境样品中金属离子的原理、流程、应用及影响因素等方面的研究进展,并相信随着研究工作的不断深入,更加理想的络合剂和ＳＣ－ＣＯ２携带剂的发现,必将使ＳＣ－ＣＯ２萃取金属离子的技术在环境样品中痕量金属离子的前处理和分析以及有害金属离子的处理等方面的应用前景更为广阔     

芳香族化合物的生物降解途径

分析了以苯、甲苯、萘和联苯为代表的芳香族化合物的生物降解途径,发现其共同点都是经过两步加氧酶作用生成二醇,最后再开环;介绍了苯、甲苯、萘和联苯这几种芳香族化合物分解酶的组分、相对分子质量及其辅基。     

重金属离子对活性污泥处理污水的影响

研究了Hg2+、Cd2+、Pb2+3种金属离子对活性污泥系统处理污水效能的影响。通过对出水理化指标和生物指标的测定反映Hg2+、Cd2+、Pb2+对活性污泥系统运转效能的影响。结果表明:实验第4 d,Hg2+(0.3、0.4、0.5和0.6 mg/L),Cd2+(15、20、25和30 mg/L)和Pb2+(300、400、600和800 mg/L)各实验组出水的COD、SVI等均有显著影响。在实验中得出,对COD影响最为明显的为浓度600 mg/L和800 mg/L Pb2+实验组,在第4 d时,出水的COD去除率已经为零。锐利楯纤虫对Hg2+的浓度变化耐受力较强;点钟虫对Cd2+的浓度变化耐受力较强;杯钟虫对Cd2+的浓度变化耐受力较强。锐利楯纤虫对Pb2+和Cd2+的浓度变化较为敏感;点钟虫对Hg2+的浓度变化较为敏感;小口钟虫对Pb2+的浓度变化较为敏感。     

川渝地区天然气钻井作业环境影响及防治措施

针对天然气钻井作业特点、川渝地区土地资源与生态环境条件,在分析天然气钻井作业对川渝地区社会环境与生态环境影响及环境污染的基础上,提出了目前川渝地区天然气钻井作业存在的环境问题,并根据这些环境问题分别在钻井不同作业过程中给出了环境防治措施。