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31.
正确理解和使用反倾销法律手段 总被引:1,自引:1,他引:0
从世界贸易组织关于反倾销的有关定义入手,结合我国现行国际贸易事务中化工行业对外反倾销调查和裁定案例,剖析了部分反倾销措施对化工产业总体发展的消极影响,提出了“综合论证”的操作方法,以降低因少数化工产品反倾销调查和裁定给国内其他产业的发展和最终消费者带来的损失。 相似文献
32.
无磷洗涤剂的现状及存在问题 总被引:1,自引:0,他引:1
含磷洗涤剂中含的“磷”主要是STPP,作用很大但对环境的危害也很大,它是造成地表水体出现富营养化的重要原因之一,所以许多地方政府都在实行“禁磷”——禁止销售、使用含磷洗涤剂。现在我国使用的无磷洗涤剂中代磷助剂主要有3种,其中4A沸石用量最大,但它会对环境带来新的问题。主要介绍了含磷洗涤剂的危害及无磷洗涤剂的应用现状,指出了我国禁磷后将面临的问题。 相似文献
33.
移动通信基站在高层建筑天台架设的定向天线,对周围环境的电磁辐射影响水平的监测进行分析,探讨高层建筑天台电磁辐射环境的污染防治对策。 相似文献
34.
对选矿废水综合利用的探讨 总被引:4,自引:0,他引:4
通过对金堆城钼业公司选矿废水再用于选矿作业的选矿试验,证明选矿废水循环利用是可行的,既提高了选矿浓度,又减少了对环境的污染,经济和社会效益显著。 相似文献
35.
Stakeholder involvement is essential to the development of a total maximum daily load (TMDL) and its implementation plan. A tool, beyond a simulation model, is needed to support the decision making process that requires negotiation and compromise among stakeholders. The decision support system (DSS) described herein has a TMDL module to calculate various combinations of point and nonpoint loads that can meet the water quality criteria. Its Consensus module allows stakeholders to formulate, evaluate, modify, and vote for alternatives. The DSS displays bar charts for pollution loads from various subwatersheds and attributes the nonpoint loads to land uses. The water quality consequence of the pollution loads is output in maps, which shows sections meeting criteria in green and those not in red. The DSS requires a front end effort of site specific adaptation and model calibration. An Internet-based stakeholder process was developed to allow more concerned citizens to participate in management decisions. 相似文献
36.
37.
aneta Polkowska Jacek Namienik Jacek Czerwiski & Bogdan Zygmunt 《International Journal of Food Science & Technology》1996,31(5):387-395
Applicability of thin-layer headspace (TLHS) procedure giving an aqueous concentrate and also classical purge and trap (PT) in off-line mode to isolate and enrich volatile organohalogen compounds in common beverages was tested. Both enrichment tech-niques were used in combination with gas chromatography – electron capture detection (GC-ECD). TLHS, combined with direct aqueous injection (DAI)-GC-ECD, proved applicable in the determination of volatile organohalogen compounds in all studied beverages, while the PT in a version with no preliminary sample pre-treatment was of limited applicability. Detection limits of the TLHS-based procedure were in the order of 1 ppt. Content of volatile organohalogen compounds in a number of beverages available on the Polish market including mineral waters, beers, juices, carbonated and non-carbonated soft drinks, etc. was determined by means of TLHS-DAI-GC-ECD. 相似文献
38.
A two-dimensional cross-section finite difference model is presented to simulate density dependent leachate migration in leaky aquifers. Unlike existing models, a new approach is adopted to couple the groundwater-flow equation and the hydrodynamic dispersion equation with the elimination of the intermediate step of calculating velocities. The concept of the reference density is employed, permitting increased accuracy (over pressure-based models) in the representation of the transport process. The model is then used to study the effect of several hydraulic and transport parameters on the flow pattern and plume migration which are found to be very sensitive to most of these parameters. Equiconcentration and equipotential lines are overlapped to provide a better understanding of the coupling effect. 相似文献
39.
Sabha Kesraoui-Ouki Christopher R. Cheeseman Roger Perry 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,59(2):121-126
This paper assesses the potential of natural zeolite utilization as a low-cost ion-exchange and sorbent material in pollution control and recovery of metals. The improvement of the purity of natural zeolites coupled with their chemical modification capabilities in order to provide specific properties may provide a cost-effective alternative for the treatment of heavy metal contaminated soil and water. The application of natural zeolites in industrial pollution control is becoming important and the level of technical effort is increasingly expanding. The extent of application is unlikely to be related solely to their low cost, but also to improved properties and performance characteristics, which will advance the practical implementation of natural zeolites' technology. 相似文献
40.