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271.
Book reviews     
Toward Sustainable Communities: resources for citizens and their governments. Mark Roseland with Maureen Cureton & Heather Wornell, 1998, Gabriola Island, New Society Publishers, ISBN 0 86571 374 X, $18.95

First Mover Advantage by Eco-efficiency: local incentives for environment and employment.. C. Erdmunger & S. Schreckenberger, 1998, Freiburg, ICLEI, DM30

Agendas for Sustainability: environment and development into the twenty-first century. Mary Macdonald, 1998, London, Routledge, ISBN 0 415 15491X, £55.00 (hbk)

Women, Population and Global Crisis: a political-economic analysis. Asoka Bandarage, 1997, London, Zed Books, ISBN 1 85649 428 4, £15.95 (pbk)

Spirit of the Environment: religion, value, and environmental concern. David Cooper & Joy Palmer (Eds), 1998, London, Routledge, ISBN 0 4151 4202 4, £12.99 (pbk)

Environmental Transition in Nordic and Baltic Countries. Hans Aage (Ed.), 1998, (New Horizons in Environmental Economics). Cheltenham, UK and Northampton, MA, USA, Edward Elgar, ISBN 1 85898 629 X

Sustainability Indicators: measuring the immeasurable. Simon Bell & Stephen Morse, 1999, London, Earthscan Publications, 175 pp. ISBN 1 85383 498 X, LE14.95 (pbk)

The Economics of Road Transport Regulation. Erik Verhoef, Cheltenham, Edward Elgar 1996, 265 pp. ISBN 1 85898 364 9, £55.00

The Water Crisis. Julie Stauffer, London, Earthscan, 1998, ISBN 185383 436X, £12.95 (pbk)  相似文献   
272.
The terrorist attacks of 11 September 2001 (9/11) left workplaces in pressing need of a mental health response capability. Unaddressed emotional sequelae may be devastating to the productivity and economic stability of a company's workforce. In the second year after the attacks, 85 employees of five highly affected agencies participated in 12 focus groups to discuss workplace mental health issues. Managers felt ill prepared to manage the magnitude and the intensity of employees' emotional responses. Rapid return to work, provision of workplace mental health services, and peer support were viewed as contributory to emotional recovery. Formal mental health services provided were perceived as insufficient. Drawing on their post‐9/11 workplace experience, members of these groups identified practical measures that they found helpful in promoting healing outside of professional mental health services. These measures, consistent with many principles of psychological first aid, may be applied by workplace leaders who are not mental health professionals.  相似文献   
273.
开发了一种矿渣硅灰混合水泥用来处理含多量Cd2+、Na2的低放射性废液.该水泥净浆经125℃蒸压14天的抗压强度达114MPa4用水银测孔仪测得总孔隙率为14.1%,最可几孔半径2.7nm.目前低放废液的处理常用硅酸盐水泥和矿渣水泥,从强度和微结构方面看,矿渣-硅灰混合水泥要比上述两种水泥好得多.对于废液中的Cd2+和Na+,成功地合成了无定形方沸石作为Na+的固主相,CdS为Cd2+的固化相.  相似文献   
274.
开发了一种矿渣硅灰混合水泥用来处理含多量Cd2+、Na2的低放射性废液.该水泥净浆经125℃蒸压14天的抗压强度达114MPa4用水银测孔仪测得总孔隙率为14.1%,最可几孔半径2.7nm.目前低放废液的处理常用硅酸盐水泥和矿渣水泥,从强度和微结构方面看,矿渣-硅灰混合水泥要比上述两种水泥好得多.对于废液中的Cd2+和Na+,成功地合成了无定形方沸石作为Na+的固主相,CdS为Cd2+的固化相.  相似文献   
275.
Pollution by polycyclic aromatic hydrocarbons(PAHs) is widespread due to tmsuitable disposal of industrial waste. They are mostly defined as priority pollutants by environmental protection authorities worldwide. Phenanthrene, a typical PAH, was selected as the target in this paper. The PAH-degrading mixed culture, named ZM, was collected from a petroleum contaminated river bed. This culture was injected into phenanthrene solutions at different concentrations to quantify the biodegradation process. Results show near-complete removal of phenanthrene in three days of biodegradation if the initial phenanthrene concentration is low. When the initial concentration is high, the removal rate is increased but 20%-40% of the phenanthrene remains at the end of the experiment. The biomass shows a peak on the third day due to the combined effects of microbial growth and decay. Another peak is evident for cases with a high initial concentration, possibly due to production of an intermediate metabolite. The pH generally decreased during biodegradation because of the production of organic acid. Two phenomenological models were designed to simulate the phenanthrene biodegradation and biomass growth. A relatively simple model that does not consider the intermediate metabolite and its inhibition of phenanthrene biodegradation cannot fit the observed data. A modified Monod model that considered an intermediate metabolite (organic acid) and its inhibiting reversal effect reasonably depicts the experimental results.  相似文献   
276.
Numerical simulations were carried out to investigate gyres within open lacustrine embayments subjected to parallel-to-shore currents. In such embayments, gyre formation occurs due to flow separation at the embayment’s upstream edge. High momentum fluid from the mixing layer between the embayment and offshore flows into the embayment and produces recirculating flow. Systematic numerical experiments using different synthetic embayment configurations were used to examine the impact of embayment geometry. Geometries included embayments with different aspect ratios, depths and embayment corner angles. The magnitudes of the recirculation and turbulent kinetic energy (TKE) in the embayment vary significantly for angles in the range 40°–55°. Embayments with corner angles less than 50° have much stronger recirculation and TKE, other parameters remaining the same. The numerical findings are consistent with gyre formation observed in two embayments located in Lake Geneva, Switzerland, and thus help explain flow patterns recorded in lacustrine shoreline regions.  相似文献   
277.
Catechol has been identified as one of the most abundant organic products in tobacco smoke and a major molecular precursor for semiquinone type radicals in the combustion of biomass material. The high-temperature gas-phase pyrolysis of catechol under hydrogen-rich and hydrogen-lean conditions was studied using a fused-silica tubular flow reactor coupled to an in-line GC/MS analytical system. Thermal degradation of catechol over temperature range of 250-1000 degrees C with a reaction time of 2.0s yielded a variety products including phenol, benzene, dibenzofuran, dibenzo-p-dioxin, phenylethyne, styrene, indene, anthracene, naphthalene, and biphenylene. Ortho-benzoquinone which is typically associated with the presence of semiquinone radicals was not observed and is proposed to be the result of fast decomposition reactions that lead to a variety of other reaction products. This is in contrast to the decomposition of hydroquinone that produced para-benzoquinone as the major product. A detailed mechanism of the degradation pathway of catechol is proposed.  相似文献   
278.
Uptake and localisation of lead in the root system of Brassica juncea   总被引:1,自引:0,他引:1  
The uptake and distribution of Pb sequestered by hydroponically grown (14days growth) Brassica juncea (3days exposure; Pb activities 3.2, 32 and 217microM) was investigated. Lead uptake was restricted largely to root tissue. Examination using scanning transmission electron microscopy-energy dispersive spectroscopy revealed substantial and predominantly intracellular uptake at the root tip. Endocytosis of Pb at the plasma membrane was not observed. A membrane transport protein may therefore be involved. In contrast, endocytosis of Pb into a subset of vacuoles was observed, resulting in the formation of dense Pb aggregates. Sparse and predominantly extracellular uptake occurred at some distance from the root tip. X-ray photoelectron spectroscopy confirmed that the Pb concentration was greater in root tips. Heavy metal rhizofiltration using B. juncea might therefore be improved by breeding plants with profusely branching roots. Uptake enhancement using genetic engineering techniques would benefit from investigation of plasma membrane transport mechanisms.  相似文献   
279.
Bottom sediments from Nakaumi Lagoon and the Honjo Area in southwest Japan were analyzed to determine their geochemical compositions and to assess potential impacts by comparison with sediment quality guidelines. Present-day water quality was also assessed. Results showed that the water quality of Nakaumi Lagoon and the Honjo area contrasts between their upper and lower parts. Average abundances of As, Pb, Zn, Cu, Ni, and Cr in the Nakaumi sediments were 12, 25, 135, 32, 21, and 46 ppm, respectively, compared to 10, 24, 110, 26, 20, and 38 ppm in the Honjo area. All averages are greater than those of the upper continental crust. The elevated metal concentrations are probably related to the fine-grained nature of the sediments, reducing bottom conditions produced by abundant organic matter and possibly minor non-point anthropogenic sources. Trace metal contents are strongly correlated with Fe2O3, suggesting that Fe oxides play a role in controlling abundances. Metal concentrations exceed the NYSDEC lowest effect level and CCME interim sediment quality guidelines that indicate moderate impact on aquatic organisms. Average abundances of As and Zn are comparable to the Coastal Ocean Sediment Database threshold, whereas maximum concentrations exceed that value, indicating that the concentrations of these metals are potentially toxic. These enrichments suggest that regular monitoring may be desirable even where no point sources of metal pollution exist.  相似文献   
280.
The Arctic is undergoing biological and environmental changes, and a coordinated effort to monitor is critical to detect these changes. The Circumpolar Biodiversity Monitoring Programme (CBMP) of the Arctic Council biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF), has developed pan-Arctic biodiversity monitoring plans that aims to improve the ability to detect and report on long-term changes. Whilst introducing this special issue, this paper also presents the making of the terrestrial monitoring plan and discusses how the plan follows the steps required for an adaptive and ecosystem-based monitoring programme. In this article, we discuss how data on key findings can be used to inform circumpolar and global assessments, including the State of the Arctic Terrestrial Biodiversity Report, which will be the first terrestrial assessment made by the CBMP. Key findings, advice for future monitoring and lessons learned will be used in planning next steps of pan-Arctic coordinated monitoring.  相似文献   
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