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1.
环境中邻苯酸酯类化合物污染研究概况   总被引:9,自引:0,他引:9  
邻苯酸酯类化合物在工农业及人们日常生活中均有广泛应用。近来它已被确认为环境激素。本文介绍该领域的研究概况,着重在北美和西欧地区对这类化合物的风险评价、雌激素活性体内和体外的测定结果以及对它的安全性看法。  相似文献   

2.
受潮汐作用的河口,地处内陆和海洋连接的咽喉处,它在经济、政治和军事诸方面都具有特殊重要意义,它给人类文明的发展提供了基地和资源。因此,一般在较大的河口都有发达的工业基地和城市。而预测这些工业和城市排放污染物所引起河口水体水质的变化,就成为一个重要的技术问题。河口的水力学情况非常复杂,它既受到潮汐、地球自转、风和密度等因素的影响,又受到底部摩擦和河口形状等的影响。与一般河流相比,周期性的潮汐是河口水力学特性的最重要标志。潮汐对污染物有两种效果相反的作  相似文献   

3.
数理统计是应用广泛的一个数学分支,它是以概率论为基础的科学,它根据试验或观察得到的数据,运用科学的方法,对研究对象的客观规律性作出种种合理的估计和判断。在环境保护工作中,我们常常会遇到许多复杂的问题,需要通过处理大量的数据,找出其规律性  相似文献   

4.
苍白杆菌还原Cr(Ⅵ)的最适条件及其豆渣培养基的优化   总被引:1,自引:1,他引:0  
利用本实验室筛选的一株苍白杆菌进行还原Cr(Ⅵ)的实验,在LB培养中它对Cr(Ⅵ)具有很强的还原能力,其最适还原条件为pH 8,温度30℃,证明它是一种专性好氧偏碱性细菌.通过在豆渣培养基中培养,并对豆渣进行优化处理,证实苍白杆菌在优化后的豆渣培养基中对Cr(Ⅵ)具有良好的还原能力.这为利用苍白杆菌处理含铬工业废渣、废液提供了廉价的培养基和为其实现工程化提供了实验依据.  相似文献   

5.
反渗透是一种膜分离技术,它借助于一个具有选择渗透性的半透膜,在一定的压力下,使溶液中某些组份分离、浓缩和提纯。自从一九六○年S.Loef和S.Sourirajan发明了不对称膜的制膜工艺以来,这种技术的应用发展得很快。它以省能、省力、省资源为特点。目前除用于咸水和海水淡化外,在食品加工、医药卫生、超纯水制备、环境治理等方面都在不断地显示它的生命力。它可有效地分离各种有毒  相似文献   

6.
新型废水处理技术——人工湿地   总被引:70,自引:0,他引:70  
人工湿地是一种新型的废水处理技术,它适用于我国广大中小城镇和乡村地区的废水处理。它不仅具有良好的有机物去除能力(BOD5和COD的处理效果可分别达85% ̄95%和80%以上),而且具有较高的除磷(达90%)和脱氮(60%)效果。此外,它还具有运转管理方便及工程造价低等优良特性。本文对人工湿地系统的基本构造、类型、运行机理以及主要工艺设计和运行控制条件作了深入的介绍,并结合有关工程实例对该工艺的经济  相似文献   

7.
美国两位地理学家根据对鹦鹉螺化石的研究,提出了一个极为大胆的见解:月亮在离我们远去,它将越来越暗。  相似文献   

8.
燃煤火力发电厂大气污染及其控制   总被引:3,自引:0,他引:3  
电能是一种优质能源,它的使用方便快捷,使其在国民经济的各个领域得到广泛应用,但火力发电厂在发电过程中排放的烟尘所造成的大气污染,也给人类带来了负面影响。文中主要谈到燃煤火力发电厂,介绍了它的燃料特性和生产,以及排放的污染物和其危害,重点列出了当前可行的控制措施。  相似文献   

9.
反硝化脱硫菌的代谢特征及其环境应用研究进展   总被引:1,自引:0,他引:1  
反硝化脱硫菌(NR-SOB)是一种具有同步硝酸盐还原和硫氧化能力的功能微生物。探讨了NR-SOB的代谢特征及其影响因素,并对它在废水处理,防腐,天然气、工业废气脱硫方面的应用进行了综述。最后,还指出了今后NR-SOB在环境应用方面的研究方向。  相似文献   

10.
TiO2光催化氧化技术是一种新型现代环境污染治理技术,它具有节能、高效、稳定和环保的特点,应用前景广阔.文中对TiO2光催化氧化机理、在环境污染治理中应用及在应用中应当解决的问题进行了论述.  相似文献   

11.
Measurements of organic compounds in air and deposition have been carried out in parallel on the Swedish west coast. In this investigation the importance of long-range transport for the occurrence of organic compounds in deposition has been studied. Air samples were collected using a high volume sampler (HVS) and the deposition was sampled on a 1 m2 Teflon-coated horizontal surface with runoff for the precipitation to an adsorbent. The samples were analyzed in order to identify and quantify different semivolatile compounds such as PAH and petrogenic hydrocarbons and chlorinated compounds such as PCB, HCH and HCB. Qualitative differences between the content of organic compounds in air and deposition during periods with varying levels of air pollution and different meteorological conditions have been studied and a comparison with other air pollutants, such as soot, has been carried out. The results of the measurements show that deposition of PAH and other hydrocarbons takes place continuously but the greatest amounts are measured in the deposition in connection with episodes together with heavy precipitation. The highest concentrations of PCB and HCH in the air were obtained during a warm dry period in May and the greatest amounts were deposited in a period in May with heavy precipitation.  相似文献   

12.
选择有代表性的芳香类有机物,在含有腐殖酸的水溶液中进行氯化试验.测定三卤甲烷和卤乙酸的生成特性.并分析有机物的化学结构对生成消毒副产物的影响.结果表明.各受试物氯化生成消毒副产物的活性和反应速率排序为间苯二酚>对苯二酚>邻苯二酚>苯酚>苯胺>苯甲酸>硝基苯;芳香类有机物苯环上官能团的性质、数量和位置等影响消毒副产物的生成;间苯二酚的氯化反应可分为快速反应阶段和慢速反应阶段.  相似文献   

13.
Carmona ER  Kossatz E  Creus A  Marcos R 《Chemosphere》2008,70(10):1910-1914
Few studies on the genotoxicity of mercury compounds have been carried out in Drosophila melanogaster, most of them focused in the effects on germinal cells, whereas studies in somatic cells are scarce. In the present study we have analyzed for the first time the genotoxic activity of mercury (II) chloride (MC) and methyl mercury (II) chloride (MMC) in the in vivo wing somatic mutation and recombination test in Drosophila, also known as the wing spot assay. This test is based on the principle that loss of heterozygosis and the corresponding expression of the suitable recessive markers, multiple wing hairs (mwh) and flare-3 (flr(3)), can lead to the formation of mutant clones in larval cells, which are then expressed as spots on the wings of adult flies. The mercury compounds were supplied to third instar larvae (72+/-2h old) at concentrations ranging from 1 to 50 microM for mercury chloride (MC) and from 0.5 to 5 microM for methyl mercury chloride (MMC). Both mercury compounds showed high toxicity; however, MMC was more toxic than MC. The results showed that none of the three categories of mutant spots recorded (small, large, and twin) increased significantly by the treatments, independently of the dose supplied, indicating that the mercury compounds tested exhibit a lack of genotoxic activity in the wing spot assay of D. melanogaster. These results contribute to increase the genotoxicity database on the in vivo evaluation of mercury compounds in Drosophila.  相似文献   

14.
双酚A和典型类固醇环境激素迁移转化研究进展   总被引:5,自引:0,他引:5  
近年来有关环境激素污染的认知、研究与防治已经开始受到全球的重视,其中双酚A(BPA)和类固醇是环境中检出频率较高的几种环境激素.国外有关BPA和类固醇环境激素的调查和其迁移转化的研究已经广泛展开,但我国仍处于起步阶段.综述了国内外BPA和两种典型类固醇激素17β-雌二醇(E2)和17α-乙炔基雌二醇(EE2)的研究进展,介绍了其基本性质、用途、危害、环境中浓度和其迁移转化规律;指出为了阐明BPA、E2和EE2在环境中危害,有关其吸附、生物降解和光降解等迁移转化规律,及各迁移转化过程之间协同作用与相互影响的研究还有待于进一步深入.  相似文献   

15.
16.
Linear relatinships between log bioconcentration factor (BCF) and log Kow for a variety of compounds have been reported many times in the literature. Analysis of the thermodynamics of the two partition processes has, however, shown that they are not analogous and that linear relationships can be expected to have different slopes for structurally unrelated compounds. In this study a set of literature lipid normalized BCF (BCFL) values of chlorbenzenes (CBs) for rainbow trout and polycyclic aromatic hydrocarbons (PAHs) forDaphnia was put together with literature Kow values. The slopes of the regression lines for log BCFL versus log Kow for the two groups of compounds proved to differ significantly in a statistical test using analysis of variance (ANOVA). The difference, which is of significance for estimates of BCFs in environmental modelling of these types of compounds, is explained by the differences in chemical structure of the two groups of compounds.  相似文献   

17.
Amat AM  Arques A  Miranda MA  López F 《Chemosphere》2005,60(8):1111-1117
The aim of this work has been to study the viability of ozone and/or UV in the treatment of cardboard industry effluents. Several model compounds have been chosen for the experiments: guaicol, eugenol, glucose, acetate and butyrate. Significant differences in the ozonisation rates are observed between phenolic products coming from lignin (eugenol and guaiacol) and aliphatic compounds. Reactions fit in all cases a pseudo-first order kinetics and are influenced by the pH of the solution. Real effluents have also been tested, and the COD decrease has been found to depend on the fatty acids/phenols ratio. Finally, respirometric studies have shown an increase in the BODst in effluents subjected to a mild oxidation, while under stronger conditions a BODst decrease is observed.  相似文献   

18.
19.
In a study of two unknown compounds in blubber of harbour seals (Phoca vitulina) of the Dutch North Sea coast combined capillary gas chromaiographic mass spectrometric data indicated the presence of trans-nonachlor and oxychlordane. These compounds have never been identified in environmental biota in The Netherlands before.  相似文献   

20.
Methyl ethers of halogenated phenols have been identified in marine air samples from the North and South Hemispheres. The compounds are tribromoanisole, pentachloroanisole and tetrachlorohydroquinone dimethyl ether. The concentrations of these compounds are in the pg m−3 range, and they are among the more abundant high-molecular weight halocarbons in the remote marine troposphere. A probable source of these compounds is the microbial methylation of the biocide pentachlorophenol and tribromophenol of either pollutant or natural origin.  相似文献   

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