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71.
介绍了APV喷雾干燥尾气的性质,原尾气系统存在的问题,改造中采取的措施、原理、流程和取得的效果。实践证明,用“麻石文丘里一次降温、洗涤—XP型塔板二次洗涤—旋流除雾器除雾”的改造方案,取代原“换热器降温—喷淋塔洗涤—折流脱水器脱水”的流程,取得了良好的降温、洗气和除雾效果,且工程费用低。 相似文献
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Bilateral cleft lip and cleft palate can be diagnosed by ultrasonography prior to 20 weeks of pregnancy. The anomaly produces an abnormal facial profile and, on cross-section, the clefts in the maxilla are demonstrable. The method is illustrated by sonograms from a fetus in which the defect was diagnosed before trisomy 13 became known by karyotyping. 相似文献
74.
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
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
75.
秦皇岛市水环境现状与恢复 总被引:1,自引:0,他引:1
秦皇岛地区原始自然环境优越,多年来,不正当的人为活动、环境恶化趋势明显,也直接干扰与影响着水的良性循环。现状水环境:河流基流渐小,并季节性断流,坑塘减少,湿地萎缩水土流失,洪径增大。地下水位下降,水量减少,承压水无序开采,污净比失衡,河流承栽力降低。地下水垂直污染面扩大,点、面、垃圾污染源趋重。联通青一洋、石一起,实施水资源再分配。优化配置城乡用水。重视地下水源地建设,联合调度地表、地下水源。谨慎开发承压水。植树造林、涵养水分。注重防风林带建设,改善田间小气候。严控地下水采量,防止土壤旱化。搞好坑塘建设,解决乡镇污水出路与净化。保护湿地,促进水的良性循环。深度处理废污水.使之资源化。从源头抓好城市三大水源地污染源.察勘储备新地下水源地。改良恢复水环境,保障水资源循环利用。 相似文献
76.
Anne Ingeborg Myhr Terje Traavik 《Journal of Agricultural and Environmental Ethics》2003,16(3):227-247
Risk governance of GM plants and GMfood products is presently subject to heatedscientific and public controversies. Scientistsand representatives of the biotechnologyindustry have dominated debates concerningsafety issues. The public is suspicious withregard to the motives of scientists, companies,and political institutions involved. Thedilemmas posed are nested, embracing valuequestions, scientific uncertainty, andcontextual issues. The obvious lack of data andinsufficient information concerning ecologicaleffects call for application of thePrecautionary Principle (PP). There are,however, divergent opinions among scientistsabout the relevance of putative hazards,definition of potential ``adverse effects,' andwhether actions should be taken to preventharm. The reliance on the concept ofsubstantial equivalence in safety evaluation ofGM food is equally controversial. Consequently,value assumptions embedded in a scientificframework may be a barrier for employment ofthe PP. One of our major conclusions is thatprecautionary GMP usage requires riskassessment criteria yet undeveloped, as well asbroader and more long-term conceptions of risk,uncertainty, and ignorance. Conflicts ofinterest and public participation are otherissues that need to be taken intoconsideration. GMP governance regimes that arejustifiable from a precautionary and ethicalpoint of view must transcend traditionalscientific boundaries to include alternativescientific perspectives as well as publicinvolvement. 相似文献
77.
Assya Pascalev 《Journal of Agricultural and Environmental Ethics》2003,16(6):583-594
Thus far, the moral debateconcerning genetically modified foods (GMF) hasfocused on extrinsic consequentialist questionsabout the health effects, environmental impacts,and economic benefits of such foods. Thisextrinsic approach to the morality of GMF isdependent on unsubstantiated empirical claimsand fails to account for the intrinsic moralvalue of food and food choice and theirconnection to the agent's concept of the goodlife. I develop a set of objections to GMFgrounded in the concept of integrity andmaintain that food and food choice can beintimately connected to the agent's personalintegrity. I argue that due to the constitutionof GMF and the manner in which they areproduced, such foods are incompatible with thefundamental values and integrity of certainindividual moral agents or groups. I identifythree types of integrity that are threatened byGMF: religious, consumer, and integrity basedon certain other moral or metaphysical grounds.I maintain that these types of integrity aresufficiently important to provide justificationfor political and societal actions to protectthe interests of those affected. I conclude byproposing specific steps for handling GMFconsistent with the moral principles ofinformed consent, non-maleficence, and respectfor the integrity of all members of society.They include mandatory labeling of GMF, theimplementation of a system for control andregulations concerning such foods, andguaranteed provision of conventional foods. 相似文献
78.
论述了用市场化模式解决三峡库区城市污水处理场和垃圾处理场的建设和运营问题,并提出了市场化的总体架构。 相似文献
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