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111.
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Carbon monoxide (CO) in the surface sea waters is produced predominantly by photochemical processes, oxidized by micro-organisms and outgassed to the atmosphere. to assess carbon monoxide flux from the oceans to the atmosphere, the photochemical production and microbial oxidation of carbon monoxide in the oceanic mixed-layer was investigated during several oeanographic cruises and in the laboratory. the photoproduction rate of carbon monoxide was found to be well correlated to the concentration of dissolved organic carbon (DOC) in coastal and open ocean surface waters. Taking a global average carbon monoxide production rate of 10 ± 2 nmole litre-1 (mg DOC hr)-1 in the surface open ocean water, and 25 ± 7 nmole litre-1 (mg DOC hr)-1 in coastal sea water, at cloud-free summer solar noon, the photochemical production of carbon monoxide in the global oceans is estimated to be at a rate of 1200 ± 200 Tg CO y-1. the microbial carbon monoxide turnover time in the mixed-layer was observed to range from hours in a coastal estuary to 16 days in the Pacific along 1057deg; W in dark incubations. Natural sunlight can largely inhibit the microbial consumption of carbon monoxide in surface water. On a global scale, microbial consumption is responsible for the loss of less than 10% of photochemical produced carbon monoxide in the surface ocean. Field measurements have shown that the net transport of carbon monoxide from the euphotic zone to the underlying deeper ocean water is limited and that the overall life time in surface sea waters is less than 3-4 hours. When combined, these field measurements with the photoproduction and microbial consumption rates obtained, we estimate the oceanic flux to the atmosphere is about 1000 ± 200 Tg CO y-1, which represents the largest single source of atmospheric carbon monoxide. 相似文献
113.
Hazel Ann Nash 《Journal of Cleaner Production》2009,17(4):496-498
The promotion of sustainable consumption and production patterns is enshrined as a key objective in the renewed European Union Sustainable Development Strategy (EU SDS). Sustainable consumption and production is arguably the most challenging aspect of the EU SDS. It requires changes to the way products and services are designed, produced, used and disposed of, taking into account producer and consumer behaviours. This paper reviews the European Commission's Communication on the sustainable consumption and production and sustainable industrial policy action plan, introduced on July 16, 2008. The paper examines the priority areas identified for action, the means adopted to improve energy and environmental performance of products as well as uptake by consumers. The paper concludes that the absence of mandatory quantifiable targets and deadlines and a reliance on both cross-sectoral and multi-level relationships are likely to weaken the ability of the action plan's fundamental objective of decoupling economic growth from resource use. 相似文献
114.
A study was conducted to screen the three passes that link Lake Pontchartrain to the Gulf of Mexico via Lake Borne for the presence of EPA base-neutral (BN) priority pollutants and any other pollutants detected in significant concentration. Biota and sediment samples were collected and analytical procedures were developed for the trace analysis of BN organics in these matrices. Compounds identified include alkanes (normal, branched, cyclic), alkenes, aromatics, alkylated aromatics, polynuclear aromatic hydrocarbons and their alkylated derivatives, phthalates, ketones, furans, thiophenes, phenols, amines, nitriles, thiazoles, amides, aldehydes, alcohols, free fatty acids, fatty acid methyl and ethyl esters, phosphates, sterols. Concentrations were in the parts-per-billion range. 相似文献
115.
Karen L. Stals Matthew Wakeling Júlia Baptista Richard Caswell Andrew Parrish Julia Rankin Carolyn Tysoe Garan Jones Adam C. Gunning Hana Lango Allen Lisa Bradley Angela F. Brady Helena Carley Jenny Carmichael Bruce Castle Deirdre Cilliers Helen Cox Charu Deshpande Abhijit Dixit Jacqueline Eason Frances Elmslie Andrew E. Fry Alan Fryer Muriel Holder Tessa Homfray Emma Kivuva Victoria McKay Ruth Newbury-Ecob Michael Parker Ravi Savarirayan Claire Searle Nora Shannon Deborah Shears Sarah Smithson Ellen Thomas Peter D. Turnpenny Vinod Varghese Pradeep Vasudevan Emma Wakeling Emma L. Baple Sian Ellard 《黑龙江环境通报》2018,38(1):33-43
针对传统教与学算法在解决复杂多峰函数优化问题时,具有局部最优且搜索开发能力较差的缺点,提出了一种改进的多学习教与学优化算法,新算法为学员的每一维加入不同的教学因子,设计了基于学员均值比较的教师选择策略和向教师及学员学习的多学习策略。基于多个单峰和多峰函数的仿真结果表明,新算法跟传统的、改进的教与学算法相比,在稳定性、寻优精度和收敛速度方面更具优势。 相似文献
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117.
Gabriela E. Jones Hatem A. Mousa Helen Rowley Peter Houtman Pradeep C. Vasudevan 《黑龙江环境通报》2015,35(13):1336-1341
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119.
The theory of neighbourhood decline due to pariah land uses: Regaining control of the downward cycle
Some neighbourhood environments have become dumping grounds for locally unwanted land uses (LULUs) that middle-class Americans do not want near their homes. LULUs may combine with other pariah land uses to collectively undermine the quality of the local environment, reduce investment, government services, the proportion of middle-income people and associated businesses. As important neighbourhood attributes are lost, illegal activities, derelict structures, trash-strewn lots and the concentration of poor and unhealthy people may increase. This paper describes the theory behind the impact of pariah land uses through examples of the downward spiral experienced by Camden, New Jersey and the south Bronx, New York. It then documents the experience of one community, Elizabethport, New Jersey, in reversing that downward spiral. Success in Elizabethport came from the synergistic activities of local, state and federal governments, community groups, and not-for-profit organizations as they struggled to regain control through local environmental management, rebuilding, and reducing crime. Social capital was also strengthened by using a local community health concern—that of childhood asthma. Efforts to reverse the downward spiral of urban decay from pariah land uses should be multi-faceted, spurred by local efforts that address local concerns. 相似文献