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761.
化工生产中硫化氢泄漏事故的预防和处置对策   总被引:2,自引:0,他引:2  
通过发生在昆明市安宁齐天化肥有限公司的硫化氢中毒事故,提出硫化氢泄漏事故的预防措施及相应的处置方法,同时总结经验教训,提出整改措施,以避免类似事故的再次发生.  相似文献   
762.
通过对某高尔夫球场运营过程中化肥和农药施用的分析,用简化模型计算了一般情况下和最不利情况下化肥、农药对地面水环境的影响,提出控制农药化肥污染的对策措施。  相似文献   
763.
随着全球经济一体化步伐的加快,中国的化工企业已呈现各种化工园区集聚发展的态势。化工园区作为地区化工行业集聚区域,也是一个地区工业经济发展的重要载体,已逐渐成为推动区域经济快速增长的重要支撑。本文分析了国内外先进化工园区管理模式及经验,总结了目前国内化工园区管理中存在的问题,通过借鉴国内外先进化工园区管理模式及成功经验,分析提出解决化工园区环境管理问题的建议,以期为改善园区管理现状、促进化工园区科学发展提供理论依据。  相似文献   
764.

Increasing concern about persistence and environmental impact of synthetic pesticide residues require development of biodegradable and environmentally safe alternatives. The potential of using fruit extracts of hot pepper as alternatives to synthetic acaricides for controlling the two-spotted spider mite, Tetranychus urticae Koch, is explored in this study. Twenty-four Capsicum accessions (Solanaceae) were screened for their toxicity and repellency to the spider mites. Crude extracts from fruits of C. chinense, C. frutescens, C. baccatum, C. annuum, and C. pubescens were prepared in methanol and tested for their acaricidal properties. Spider mite mortality was greatest (45%) when fruit extract of accession Grif-9169 (C. annuum) was used. Results from diving board bioassays indicated that mites avoided filter paper strips treated with hot pepper extracts from accessions PI-596057 (C. baccatum), PI-195299 (C. annuum), and Grif- 9270 (C. annuum). This investigation suggests that methanolic extracts of these three accessions may have a great potential for repelling spider mites and should be field-tested on a large-scale to assess their value in managing populations of spider mites, which could reduce reliance on synthetic acaricides. An attempt was made to correlate repellency with chemical constituents of fruit extracts of the most repellent accessions to identify chemical sources of repellency. Capsaicin and dihydrocapsaicin, the pungent components of pepper fruit, were not correlated with toxicity or repellency, indicating that these are not likely related to the toxicity or repellency of the pepper fruit extracts. Other, unidentified chemicals are likely responsible for toxicity and repellency to the two-spotted spider mite  相似文献   
765.
Vinclozolin, a dicarboximide fungicide, is an endocrine disrupting chemical that competes with an androgenic endocrine disruptor compound. Most research has focused on the epigenetic effect of vinclozolin in humans. In terms of ecotoxicology, understanding the effect of vinclozolin on non-target organisms is important. The expression profile of a comprehensive set of genes in the amphipod Hyalella azteca exposed to vinclozolin was examined. The expressed sequence tags in low-dose vinclozolin-treated and -untreated amphipods were isolated and identified by suppression subtractive hybridization. DNA dot blotting was used to confirm the results and establish a subtracted cDNA library for comparing all differentially expressed sequences with and without vinclozolin treatment. In total, 494 differentially expressed genes, including hemocyanin, heatshock protein, cytochrome, cytochrome oxidase and NADH dehydrogenase were detected. Hemocyanin was the most abundant gene. DNA dot blotting revealed 55 genes with significant differential expression. These genes included larval serum protein 1 alpha, E3 ubiquitin-protein ligase, mitochondrial cytochrome c oxidase, mitochondrial protein, proteasome inhibitor, hemocyanin, zinc-finger–containing protein, mitochondrial NADH-ubiquinone oxidoreductase and epididymal sperm-binding protein. Vinclozolin appears to upregulate stress-related genes and hemocyanin, related to immunity. Moreover, vinclozolin downregulated NADH dehydrogenase, related to respiration. Thus, even a non-lethal concentration of vinclozolin still has an effect at the genetic level in H. azteca and presents a potential risk, especially as it would affect non-target organism hormone metabolism.  相似文献   
766.
Abstract

Inundatively used mycoherbicides have been uneconomical and ineffectual, mainly because a large inoculum is required to overcome weeds’ innate defenses, as well as the need for long dew periods to become established. Weed defenses can be suppressed by specific chemical agents, or overcome biologically (using mixed organisms and/or engineering enhanced pathogenicity), and better formulants replace the long dew periods.  相似文献   
767.
氯离子对COD测定影响的探讨   总被引:1,自引:0,他引:1  
研究含有高氯离子样品COD的测定,发现其中的白色沉淀为AgCl。实验结果证明,按照标准方法,当取样体积为20 mL时,按0.4 g HgSO4络合2 000 mg/L Cl-的比例投加掩蔽Cl-可以取得理想的效果。  相似文献   
768.
为确保公众与化工园区之间的和谐相处,分析化工园区综合风险评价中公众参与的现状,提出公众参与实施中所应遵循的原则、方法和形式,采用社会问卷调查的形式,验证了这一工作的必要性。阐述化工园区综合风险评价中公众参与应分为三个阶段,即早期公众参与、中期公众参与及持续公众参与,针对不同时期的具体情况,指出基本的工作程序。在公众参与调查中建立评价因素集的体系框架,并采用熵权法分析评价各因素的权重,结合公众"幅值"评分,综合得出公众对于化工园区建设、规划、准入项目及正常生产时带来影响的意见和建议的倾向性。首次提出在化工园区综合风险评价中增加公众参与这一内容,有利于增加政府机构办事的透明度,同时也确保公众的利益得到足够的重视。  相似文献   
769.
Deep waters of the Sea of Japan and surface waters of the Pacific Coast of Honshu and the northeast Sea of Japan were analysed for polychlorinated biphenyls (PCBs) pollution. the ΣPCB concentrations in solution in the Sea of Japan (50-3000 m) were between 140 and 1230 fg dm-3. the space-integrated surface water concentration near the Pacific coast of northern Honshu was 140 fg dm-3and for the surface water of the Sea of Japan was 230 fg dm-3. Based on these analyses four water masses were deduced in the Sea of Japan during the summer months. It is shown for the first time in the Sea of Japan that polychlorinated biphenyls are excellent chemical indicators of not only the anthropogenic pollution, but also water masses.  相似文献   
770.
系统分析了我国现阶段化工园区的基本特点及其安全监管中存在的问题,提出了建立以政府为主导、社会中介机构技术支撑、企业落实一体化的化工园区综合管理体系。实现化:亡园区应急救援资源整合及资源共享,提高化工园区应急救援资源有效利用率。数字化管理对化工园区的整体安全性的提高将发挥巨大的作用。  相似文献   
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