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排序方式: 共有99条查询结果,搜索用时 15 毫秒
1.
筛网处理装置治理厨房油雾烟气的方法与研究   总被引:1,自引:0,他引:1  
筛网处理装置是沈阳环境科学研究所经过多年研制出的具有用途广泛、效果显著的一种新技术。它曾应用于锅炉除尘脱硫、喷漆尾气的净化等环境治理工程。本方法是利用筛网处理装置技术的拓宽研究  相似文献   
2.
高效菌活性污泥法处理分散染料废水实验研究   总被引:6,自引:1,他引:6  
张丽  贺启环 《环境工程》2002,20(1):77-79
针对复合微生物的筛选和分离进行了研究 ,分离出处理分散染料废水起高效降解作用的 2株菌种。结果表明 ,2株高效菌对分散染料废水降解能力很强 ,与普通菌结果对比CODCr去除率提高 17% ,并且高效菌对废水浓度的耐受性也明显提高  相似文献   
3.
介绍了由PLC和触摸屏组成的控制系统的特点和功能,以及PLC和上位机构成的控制系统可实现污水处理整个过程的实时监测和控制。  相似文献   
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Background, aim and scope

Estrogenic and non-estrogenic chemicals typically co-occur in the environment. Interference by non-estrogenic chemicals may confound the assessment of the actual estrogenic activity of complex environmental samples. The aim of the present study was to investigate whether, in which way and how seriously the estrogenic activity of single estrogens and the observed and predicted joint action of estrogenic mixtures is influenced by toxic masking and synergistic modulation caused by non-estrogenic chemical confounders.

Materials and methods

The yeast estrogen screen (YES) was adapted so that toxicity and estrogenicity could be quantified simultaneously in one experimental run. Mercury, two organic solvents (dimethyl sulfoxide (DMSO) and 2,4-dinitroaniline), a surfactant (LAS-12) and the antibiotic cycloheximide were selected as toxic but non-estrogenic test chemicals. The confounding impact of selected concentrations of these toxicants on the estrogenic activity of the hormone 17ß-estradiol was determined by co-incubation experiments. In a second step, the impact of toxic masking and synergistic modulation on the predictability of the joint action of 17ß-estradiol, estrone and estriol mixtures by concentration addition was analysed.

Results

Each of the non-estrogenic chemicals reduced the apparent estrogenicity of both single estrogens and their mixtures if applied at high, toxic concentrations. Besides this common pattern, a highly substance- and concentration-dependent impact of the non-estrogenic toxicants was observable. The activity of 17ß-estradiol was still reduced in the presence of only low or non-toxic concentrations of 2,4-dinitroaniline and cycloheximide, which was not the case for mercury and DMSO. A clear synergistic modulation, i.e. an enhanced estrogenic activity, was induced by the presence of slightly toxic concentrations of LAS-12. The joint estrogenic activity of the mixture of estrogens was affected by toxic masking and synergistic modulation in direct proportion to the single estrogens, which allowed for an adequate adaptation of concentration addition and thus unaffected predictability of the joint estrogenicity in the presence of non-estrogenic confounders.

Discussion

The modified YES proved to be a reliable system for the simultaneous quantification of yeast toxicity and estrogen receptor activation. Experimental results substantiate the available evidence for toxic masking as a relevant phenomenon in estrogenicity assessment of complex environmental samples. Synergistic modulation of estrogenic activity by non-estrogenic confounders might be of lower importance. The concept of concentration addition is discussed as a valuable tool for estrogenicity assessment of complex mixtures, with deviations of the measured joint estrogenicity from predictions indicating the need for refined analyses.

Conclusions

Two major challenges are to be considered simultaneously for a reliable analysis of the estrogenic activity of complex mixtures: the identification of known and suspected estrogenic compounds in the sample as well as the substance- and effect-level-dependent confounding impact of non-estrogenic toxicants.

Recommendations and perspectives

The application of screening assays such as the YES to complex mixtures should be accompanied by measures that safeguard against false negative results which may be caused by non-estrogenic but toxic confounders. Simultaneous assessments of estrogenicity and toxicity are generally advisable.  相似文献   
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经过实验分离到一株纤维素降解真菌CD-Q1,通过形态及分子生物学鉴定该真菌为匍匐根霉。该菌能够以滤纸、秸秆和脱酯棉为唯一碳源生长,8 d内可将26.5%的秸秆降解,可将7.5%的滤纸糖化。当以滤纸为唯一碳源时,pH=5条件下,滤纸失重及还原糖产生量最高,45 h内可将3%滤纸降解,生成0.845 mg/ml的还原糖(以葡萄糖计)。该纤维素降解真菌的分离为纤维素糖化及进一步利用提供了较好菌源,为纤维素降解性能的基因改良提供了理想的出发菌株。  相似文献   
8.
ABSTRACT: Data from 54 well in central and eastern Kansas developed in unconsolidated deposits of Quaternary age indicate that nitrate concentrations are inversely related to the depth of the well screen opening below the water level in the well casing because this relationship was found to exist in an area of Nebraska and in a large area of Kansas, the relationship is generally valid over a wide geo- graphical area. In addition, the data indicate that the incidence of nitrate concentrations exceeding 45 milligrams per liter and nitrate concentrations, in general, are significantly lower in water from wells with screens deeper than 25 feet below the water table in unconfined aquifers or where screens are placed in deep confined aquifers. No concentrations of nitrate greater than 45 milligrams per liter were in obseved wells where screens were deeper than 60 feet below the casing water level. These findings suggest that general placement of well screens as far below the water table as possible in unconfined unconsolidated aquifers in Kansas. and possibly other areas of the Midwest, may be an effective measure in preventing undesirable nitrate concentrations in ground water supplies. particularly in areas where nitrate is a problem.  相似文献   
9.
针对军事上大量使用的液体烟幕的残留物所存在的严重污染问题,研究了利用氨水的自净化法。探讨了自净化的机理和氨水的不同浓度、不同用量对净化效果的影响。该方法简单、高效,既可保持烟幕本身的功用特性,又可解决其残留物的严重污染问题,具有重要的环保价值,也是在军事运用中强调环保的一种有益尝试。  相似文献   
10.
本文以制作赤峰市环保触摸屏查询系统为例,介绍了一种使用Authorware7.0作为开发工具来设计查询界面的方法,使之实现了在环保工作中应用的功能。  相似文献   
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