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1.
李雪松 《交通环保》2000,21(1):38-41
国际海事组织目前正在对《MARPOL73/78公约》附则Ⅱ-控制散装液体有毒物质污染规则作重大修改,内容包手胡毒液体物质和化学品,这很可能对主管机关、船公司和化工界造成严重的冲击。  相似文献   
2.
The Minicontainer-test, first described by Eisenbeis (1993), was designed to study the kinetics of organic residue decomposition at a microsite level. It is derived from the litterbag technique and consists of polyethylene minicontainers (volume about 1.5 cm3) filled with a test substrate (litter, straw, cellulose, etc.). The minicontainers (MCs) are closed at either end with plastic gauze discs of variable mesh size (e.g. 20 μm, 250 μm, 500 μm or 2 mm). A definite number of such units are inserted into PVC-bars, which can be implanted into the soil horizontally or vertically, or be exposed on the soil surface horizontally. The bars are very stable and can be exposed in different environments for months to years. If required, the bars can be removed temporarily and stored, e.g. during soil cultivation. Should fresh litter be used, two phases of decomposition can be distinguished: a fast initial phase, which can be mainly related to the effect of leaching, and a second slow phase depending mainly on the activity of soil organisms and litter quality. Several questions can be addressed to investigations using MCs, e.g. 1) parts of the soil fauna which are involved in decomposition (nematodes, microarthropods, and smaller specimens of the macrofauna, e.g. enchytraeidae, diplopods and dipteran larvae) can be extracted from the litter substrate using a miniscale high gradient extractor, 2) the organic mass loss of litter can be determined, 3) microbial biomass (Cmic, Nmic) can be assessed by fumigation extraction and 4) microbial activity (respiration) in the test substrate can also be assessed by use of standardised methods. Compared to litterbag studies, the larger number of small replicate units improves the statistical evaluation. Until today the Minicontainer-test has been applied in forestry and agriculture, e.g. studying the effects of liming, soil restoration and the application of insecticides, e.g. Diflubenzuron (Dimilin) and Btk (Bacillus thuringiensis var.kurstaki).  相似文献   
3.
沉淀--吸附处理双氯灭痛高浓度有机废水的工艺研究   总被引:10,自引:0,他引:10  
介绍了用沉淀-吸附法处理双氯灭痛高浓度有机废水的工艺。先用废盐酸将废水的pH调节到4,沉淀、过滤,然后将滤液依次经过炉渣、生炭串级吸附,处理后的废水CODCr、pH、SS均达到GB8978-88污水综合排放制药行业二级标准。  相似文献   
4.
车内空气中挥发性有机物的研究   总被引:1,自引:0,他引:1  
采用热脱附-气相色谱/质谱联用法对4辆处于静止状态下的车辆内部空气中挥发性有机物(VOCs)进行了研究,共定性检出了48种有机物,其中C6~C9之间的组分较多;并对VOCs的总浓度进行了定量,1#~4#车分别为1846、2289、1104和3146 μg/m^3;其中BTEX占VOCs总量的20%~30%;车内VOCs浓度与温度及车辆使用年限密切相关.  相似文献   
5.
介绍了工厂有机溶剂废气处理方案和设计及实际运行效果,具有简单经济、净化彻底的特点.  相似文献   
6.
活性炭吸附室内空气中挥发性有机化合物   总被引:13,自引:0,他引:13  
活性炭吸附室内空气中挥发性有机化合物的10%穿透时间与气相浓度及挥发性有机化合物的种类有关,通过对苯、甲苯和丙酮的实验研究,得出了由高浓度估算室内低浓度时炭床10%穿透时间的经验公式tb,1=tb,h(C0,1/C0,h)^a,其中a值是与炭床性能及挥发性有机化合物种类有关的参数,可通过实验确定。  相似文献   
7.
Franke R  Franke C 《Chemosphere》1999,39(15):219-2659
A laboratory scale flow-through model reactor for the degradation of persistent chemicals using titanium dioxide (TiO2) as photocatalyst immobilized on glass beads is presented. In the test system with a volume of 18 L contaminated water is pumped to the upper part of the floating reactor and flows over the coated beads which are exposed to UV-radiation. The degradation of two dyes of different persistance was investigated. Primary degradation of methylene blue did not fit a first order kinetic due to coincident adsorption onto the photocatalyst and direct photolysis, resulting in a half-life of 6 h. A filtrate of a green algae suspension accelerated the colour removal. In contrast, reactive red 2 was degraded only by photocatalysis; neither adsorption nor direct photolysis led to a colour removal. The course of primary degradation followed a first order kinetic with a half-life of 18 h and a rate constant of 0.04 h−1. Analysis of the degradation products indicated mineralization by detection of NO2 and NO3, accompanied by a decrease of pH and an increase of conductivity. A successful adaptation of the model reactor (scale 1:10) to dimensions required for surface waters and waste water treatment plants would be a costefficient and environmentally sustainable application of photocatalysis for the treatment of industrially polluted water and could be of relevance for third world contries, particularly those favoured by high solar radiation.  相似文献   
8.
中国居民及动植物的环境激素暴露研究现状和建议   总被引:1,自引:0,他引:1  
环境激素污染严重威胁着人类及动植物的健康。综述了EDCs生物危害,简要介绍了美国、日本和欧盟的EDCs研究工作,分析了中国居民和动植物的EDCs暴露现状,归纳了现有的流行病学调查信息,并针对现状提出了建议。  相似文献   
9.
Goal, Scope and Background In order to evaluate the estrogenic activity of sediments and XAD water extracts of selected sites of the catchment area of the River Neckar, a river system in Southern Germany, an integrative assessment approach was used to assess the ecological hazard potential of endocrine-disrupting compounds in sediment and water. Methods The approach is based on estrogen receptor-mediated vitellogenin synthesis induced in isolated hepatocytes of rainbow trout and quantified in a non-radioactive dot blot/RNAse protection-assay in parallel to comprehensive chemical analyses of estrogenic substances. Results and Discussion Numerous investigated extracts revealed an estrogen activity comparable to that of the positive control (1 nM 17?-estradiol corresponding to 270 ng/L in the test medium). Based on a concentration factor of 30 in the extracts and a recovery of XAD resins of approximately 80 %, 17?-estradiol equivalent concentrations between 20 and 26.7 ng/L could be calculated downstream of a sewage treatment plant (< 0.1 ng/L for a reference site). A comparison of the bioassay-derived Bio-TEQs (toxicity equivalents) and the Chem-TEQs revealed a high correlation with a Pearson coefficient of 0.85, indicating that the same ranking of the samples could be obtained with respect to the endocrine disrupting potential with both chemical and bioanalytical analysis. However, the TEQ concentrations computed from chemical analyses were significantly lower than the bioassay-derived TEQ concentrations. In fact, in none of the samples, more than 14 % of the vitellogenin-inducing potency could be attributed to the substances (steroids, alkylphenols, bisphenol A, diethylstilbestrol) analyzed. A comparison of the endocrine disrupting potential of sediments extracted by the solvents acetone and methanol revealed lower biological effects for acetone-extracted samples. Possible reasons may be a masking of endocrine effects in acetone extracts by cytotoxicity, a low extraction efficiency of the solvent acetone, or anti-estrogen potencies of some extracted sediment compounds. Using a mass balance approach, the contribution of the compounds analyzed chemically (Chem-TEQs) to the total endocrine activity (Bio-TEQs) was calculated. Based on the very low detection limits, particularly of the steroids with their high TEF factors, results revealed that a calculation of the Chem-TEQs is associated with considerable scale inaccuracy: Whereas only 7-15 % of the biological effectiveness (Bio-TEQs) could be explained by endocrine substances identified above the detection limits, the assumption of concentrations slightly below the given detection limits would result in a significant over estimation (137-197 %) of the Bio-TEQs. Even the interassay variation of the dot blot assay with different fish donors for primary hepatocyte (factor 2 - 2.5) is relatively low, when compared to the large range of the Chem-TEQ concentrations (factor 20) obtained when applying different modes of calculation. Conclusions and Outlook Overall, only a minor portion of the endocrine activity detected by bioassays could be linked to compounds identified by chemical analysis. In vitro assays for assessment of endocrine activities are useful as sensitive integrating methods that provide quantitative estimates of the total activity of particular receptor-mediated responses. Although discrepancies may also result from different bioanalytical approaches, it is overall likely that bioanalytical and not chemical analytical approaches give the correct estimate of endocrine disrupting potencies in environmental samples. As a conclusion, assessment of endocrine disruption based on chemical analysis alone does not appear sufficient and further research into the spectrum of substances with potential endocrine activity as well as into additive or even synergistic effects in complex environmental samples is urgently needed.  相似文献   
10.
Reactive volatile organic compounds (VOCs) are known to affect atmospheric chemistry. Biogenic VOCs (BVOCs) have a significant impact on regional air quality due to their large emission rates and high reactivities. Diterpenes (most particularly, kaur-16-ene) were detected in all of the 205 enclosure air samples collected over multiple seasons at two different sites from Cryptomeria japonica and Chamaecyparis obtusa trees, the dominant coniferous trees in Japan,. The emission rate of kaur-16-ene, was determined to be from 0.01 to 7.1 μg dwg−1 h−1 (average: 0.61 μg dwg−1 h−1) employing branch enclosure measurements using adsorbent sampling followed by solid phase-liquid extraction techniques. The emission rate was comparable to that of monoterpenes, which is known major BVOC emissions, collected from the same branches. In addition, total emission of kaur-16-ene at 30 °C was estimated to exceed that of total anthropogenic VOC emissions.  相似文献   
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