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581.
582.
目前地面常规大气监测手段难以对垂直方向污染源监测,也难以应对环境突发事件,采用无人机大气监测与数值模拟结合的方法可以解决该问题。实验开发了基于无人机平台的空气质量监测平台,采用数值模拟方法确定平台搭载方案,再对无人机监测系统得到的监测数据与数值模拟计算结果作对比分析,得到各项污染物浓度。分析了该方法存在的问题,提出了提高数据链路传输能力,开展无人机遥感系统相关环境质量评价方法学研究,开发精度高、质量轻的无人机大气监测吊舱,开展地面静止比对和飞行测量比对实验等建议。 相似文献
583.
利用物料衡算和源排放测试对江苏省典型汽车涂装企业VOCs排放特征进行研究,并提出最佳治理技术。结果表明,大客车单位涂装面积VOCs排放量达到300 g/m2以上,小轿车为40~60 g/m2。苯系物是VOCs排放的重要组分,最高占比为33.2%~64.6%。乙酸丁酯、异丙醇、丁醇等醇酯类物质近年来广泛用于代替苯系物溶剂,其排放占比为29.6%~61.2%。汽车涂装行业最佳治理技术包括采用3C1B、水性免中涂等先进涂装工艺,用粉末涂料、水性涂料和高固体成分涂料等代替溶剂型涂料,从源头控制排放。采用干式漆雾分离技术、转轮浓缩吸附-蓄热式焚烧技术等先进尾气治理技术,VOCs去除率可达99%以上。 相似文献
584.
The Vegetation of Wet Meadows in Relation to Their Land-use 总被引:5,自引:0,他引:5
Susan M. Galatowitsch Diane C. Whited Richard Lehtinen Jason Husveth Karen Schik 《Environmental monitoring and assessment》2000,60(2):121-144
Wetland biomonitoring approaches are needed to determine when changes in response to stressors are occurring and to predict the consequences of proposed land-use changes. These approaches require an understanding of shifts in biota that occur in response to land-use, data that are lacking for most kinds of wetlands. Changes in floristic composition corresponding to land-use differences at multiple scales (site to 2500 m radius) were characterized for 40 wet meadows associated with prairie glacial marshes in Minnesota (U.S.A.). In general, guild was more useful than species composition for indicating land-use impacts. Site impacts (stormwater, cultivation) and landscape disturbance (agriculture and urbanization, combined), coincide with a reduction in native graminoid and herbaceous perennial abundance (e.g., Carex lasiocarpa, Calamagrostis canadensis, Spartina pectinata). This vegetation is replaced with annuals (e.g, Bidens cernua, Polygonum pensylvanicum) in recently cultivated sites or introduced perennials (e.g., Phalaris arundinacea, Typha angustifolia) and floating aquatics (lemnids) in stormwater impacted wetlands. Ditches also reduce native perennial importance and increase perennials, but only when they are in highly impacted landscapes. 相似文献
585.
为了认识岩溶区石灰土含水介质中化学氧化联合生物降解去除燃油苯系物的效果,以汽油中的苯、甲苯、乙苯和二甲苯(BTEX)作为污染物,通过批实验研究过硫酸盐(PS)联合硝酸盐去除汽油BTEX的效果,并认识不同浓度乙醇(EtOH)存在时带来的影响及化学氧化与反硝化联合修复的可能性.结果表明,在35 d内各组的BTEX去除率均达到91.00%以上,PS化学氧化能有效地去除BTEX.在不含EtOH及含EtOH初始浓度为500和5000 mg·L-1的情况下,BTEX浓度在第65 d时分别为未检出、0.226 mg·L-1、0.243 mg·L-1,去除率分别为99.98%、99.00%、98.70%,其中,苯的去除率分别为99.98%、97.01%、93.32%.随着EtOH浓度的增加,苯的去除受到抑制,EtOH对BTEX的化学氧化具有阻碍作用.石灰土介质中高铁含量对PS具有活化能力,高含量有机质能促进PS分解,并导致pH值回升,出现反硝化作用和硫酸盐还原作用,有利于生物降解作用的恢复. 相似文献
586.
Fenton process, as a pretreatment method, was found to be effective in the primary treatment of mature/medium landfill leachate. However, the main problem of the process is the large amount of produced sludge that requires an accurate feasibility evaluation for operational applications. In this study, the response surface methodology was applied for the modeling and optimization of Fenton process in three target responses, (1) overall COD removal, (2) sludge to iron ratio (SIR) and (3) organics removal to sludge ratio (ORSR), where the latter two were new self-defined responses for prediction of sludge generation and applicability assessment of the process, respectively. The effective variables included the initial pH, [H2O2]/[Fe2+] ratio and Fe2+ dosage. According to the statistical analysis, all the proposed models were adequate (with adjusted R2 of 0.9116–0.9512) and had considerable predictive capability (with prediction R2 up to 0.9092 and appropriate adequate precision). It was found that all the variables had significant effects on the responses, specifically by their observed role in dominant oxidation mechanism. The optimum operational conditions obtained by overlay plot, were found to be initial pH of 5.7, [H2O2]/[Fe2+] ratio of 17.72 and [Fe2+] of 195 mM, which led to 69% COD removal, 2.4 (l sludge/consumed mole Fe2+) of SIR and 16.5 (gCOD removed/l produced sludge) for ORSR in verification test, in accordance with models-predicted values. Finally, it was observed that [H2O2]/[Fe2+] ratio and Fe2+ dosage had significant influence on COD removal, while Fe2+ dosage and [H2O2]/[Fe2+] ratio had remarkable effects on SIR and ORSR responses, respectively. 相似文献
587.
Brian Furze 《Journal of Agricultural and Environmental Ethics》1989,2(1):59-67
Food is a basic human need and therefore a basic human right. While food output has increased to a level where there is enough food produced to feed the world, still millions starve. Using the concept of capitalist world economy as a framework, this paper provides a structural analysis of the food production and distribution system within monopoly capitalism and its implications for countries of the underdeveloped world. Focusing on the impact of a dominant world food supply system on indigenous systems (particularly through the rise of science, technology, and monopoly capital), considerations relating to environmental use and food production and distribution are raised. Finally a call is made for a new agricultural ethic. 相似文献
588.
本文提出安全科学技术也是第一生产力的观点。文中简析了科学、技术和科学技术的内涵及其相互关系;研究了科学技术与生产力的关系;阐述安全科学技术也是第一生产力:探讨了发展高科技与安全科学技术的关系;安全科学技术发展中应注意的问题。 相似文献
589.
Robert J. Langridge Bryan D. MacGregor 《Journal of Environmental Planning and Management》1986,29(1):19-22
This study analyses the behaviour of high technology and new firms in the Newbury District of Berkshire in terms of employment, location, genealogy, and local economic impact. It finds that encouraged by good communications networks and a ‘resident electronics establishment’, the direct, as opposed to the indirect, employment consequences are generally encouraging, but not widely replicable. Moreover, the general picture of employment growth masks important differences in labour demand across occupations, particularly with respect to ‘traditional male’ skilled manual workers. 相似文献
590.
Ulf Wiberg 《Journal of Environmental Planning and Management》1986,29(2):70-74
The computer and telecommunications technology has created new opportunities for developing interaction between offices and enterprises located far away from each other. Even if the market forces favour concentration to R & D centres in the big cities and in university towns, there are expectations that the distance over‐bridging qualities of the new technology can create development opportunities for sparsely populated peripheral areas. In this paper the interplay between the new technology and other important factors in the local and regional environment are discussed with the focus on both opportunities and restrictions. 相似文献