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521.
在济南市区设11个点位,在不同季节采集大气颗粒物,其中五个点位用六级串级式采样器采集飘尘样。样品分析了40多种元素、非金属和有机物,并分析了不同粒径中苯并(a)芘含量。应用富集因子计算并提出富集值大干5(EF>5)为污染富集的论点;摸清了济南大气颗粒物的理化特征及粒径分布规律;用化学质量平衡(CMB_7)法探寻了颗粒物来源。  相似文献   
522.
Book reviews     
The Garden City Utopia

Robert Beevers. The Macmillan Press, 1988. £27.50. 206 pages.

Cost‐Benefit Analysis in Urban and Regional Planning

J. A. Schofield. Allen and Unwin, London, 1987. 249 pages. £30 hardback.

The Milton Park Affair — Canada's largest citizen‐developer confrontation

Claire Helman. Véhicule Press, Montréal, 1987. $12.95.

Regenerating the Inner City, Glasgow's Experience

Edited by David Donnison and Alan Middleton. Routledge & Kegan Paul Ltd., London, 1987. £12.95.

Community Architecture

Nick Wates and Charles Knevitt. Penguin Books, London, 1987. £4.95.  相似文献   

523.
Joint chemical flushing of soils contaminated with petroleum hydrocarbons   总被引:7,自引:0,他引:7  
How to increase the efficiency of chemical flushing and decrease the remediation expenses of contaminated soils are two key scientific and technological issues to be solved. Joint chemical flushing was tested and compared with the water-flushing. The joint acid-flushing could effectively remove petroleum hydrocarbons in contaminated aquorizem and the dosage of washing powder as a flushing agent was greatly reduced, thereby, saving approximately 1200 US dollars of expenses relative to the water-flushing. The joint salt-flushing could be an optimal method for the cleanup of meadow burozem contaminated with petroleum hydrocarbons under the experimental conditions. Moreover, the amount of surfactant remained in the two washed soils after the joint acid-flushing and the joint-salt-flushing was minimal.  相似文献   
524.
INTRODUCTION: Selective Traffic Enforcement Programs (sTEPs) are a proven method to change motorists' behavior. Since 1997, the Connecticut DOT's Division of Highway Safety has organized a statewide seat belt enforcement program, with sTEP waves every three or four months. To date, 28 waves have been implemented. METHOD: Pre-wave and post-wave seat belt observation surveys are conducted by both state and municipal police across the state. Survey results, as well as a summary of all enforcement activity during the wave, are submitted for evaluation. RESULTS: Connecticut seat belt use has continued to rise from one wave to the next in a predictable "saw blade" pattern. CONCLUSIONS: The data clearly demonstrate that agencies that have participated in a greater number of waves have experienced the greatest increase in belt use. Belt use has not yet plateaued and additional sTEP enforcement seems indicated. However, evidence from other states suggests that a plateau may occur somewhere in the mid 80% range. IMPACT ON INDUSTRY: Should this occur, Connecticut will work toward strengthening the round the clock model, emphasizing the importance of aggressive primary enforcement.  相似文献   
525.
The measurement of experienced burnout   总被引:1,自引:0,他引:1  
A scale designed to assess various aspects of the burnout syndrome was administered to a wide range of human services professionals. Three subscales emerged from the data analysis: emotional exhaustion, depersonalization, and personal accomplishment. Various psychometric analyses showed that the scale has both high reliability and validity as a measure of burnout.  相似文献   
526.
随着石油化工企业应用放射源数量的不断增多,放射源的安全管理已经成为石化企业安全管理工作的重要组成部分,尤其是废弃、闲置的放射源,存放不当或保存时间过久很容易丢失.对此,国家和中国石化集团公司高度重视,陆续颁布了一系列新的法规、规定.如国务院新修订的<放射性同位素与射线装置安全和防护条例>从2005年12月1日起实施,中国石化集团公司安全环保局也于2004年新修订了<放射防护管理规定>,并实行射线作业票制度.在中国石化集团公司历年安全大检查中,加大了对放射源的安全检查力度,放射源安全检查成为每次安全检查的必检内容.  相似文献   
527.
危险化学品事故应急救援预案编制过程问题讨论   总被引:4,自引:0,他引:4  
通过对编制危险化学品事故应急救援预案过程中若干问题的思考,探讨如何按国家安全生产监督管理总局颁布的<危险化学品事故应急救援预案编制导则(单位版)>的要求,结合石化企业的实际情况,编制或修订详细完善的危险化学品事故应急救援预案.  相似文献   
528.
Exotic species have been observed to be more prevalent in sites where the richness of native species is highest, possibly reflecting variation among sites in resources, propagule supply, heterogeneity, or disturbance. However, such a pattern leaves unclear whether natives at species-rich sites are subject to especially severe impacts from exotics as a result. We considered this question using path models in which relationships between exotic cover and native richness were evaluated in the presence of correlated environmental factors. At 109 sites on serpentine soils across California, USA, exotic cover was positively correlated with total native herbaceous richness and was negatively correlated with the richness of both serpentine-endemic and rare native herbs. However, in path models that accounted for the influences of soil chemistry, disturbance, overstory cover, and regional rainfall and elevation, we found no indication that exotic cover reduced any component of native herb richness. Rather, our results indicated similarities and differences in the conditions favoring exotic, native, endemic, and rare species. Our results suggest that, in spite of some localized impacts, exotic species are not exerting a detectable overall effect on the community richness of the unique native flora of Californian serpentine.  相似文献   
529.
Although choristoderes have a good Lower Cretaceous record in Asia, they have never previously been recorded from Jurassic deposits. Here we describe fragmentary vertebral material referable to Choristodera indet. from the Middle Jurassic Balabansai Svita of the Fergana Valley, Kyrgyzstan. This provides a significant range extension for the group in Asia and shows that choristoderes already had a Pan-Laurasian distribution in the Jurassic.  相似文献   
530.
高效厌氧产甲烷颗粒污泥中微生物多样性及定量化研究   总被引:4,自引:4,他引:0  
孙寓姣  左剑恶  邢薇  李建平  鲁颐琼 《环境科学》2006,27(11):2354-2357
以小试高效厌氧反应器不同运行阶段的颗粒污泥为对象,利用变性梯度凝胶电泳(DGGE)、荧光原位杂交(FISH)和实时定量链式聚合酶反应(RTQ-PCR)等技术研究了其中微生物种群的多样性、特征微生物的空间分布和定量关系,结果表明:随着反应器有机负荷逐渐提高,颗粒污泥中古菌的群落结构的变化较细菌更为明显;细菌多分布在颗粒外层,而古菌则主要分布在颗粒内层;古菌含量略少于细菌,但有逐渐增多的趋势;产甲烷丝菌在古菌中的含量增加明显.  相似文献   
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