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901.
解立芳 《中国环境管理干部学院学报》2010,20(3):47-48,57
低碳生活是一种自然地节约各种资源的习惯,是一种生活习惯。气候变化是本世纪最严重的全球问题之一,不断推进低碳生活是减少人类生活对气候影响的重要途径。低碳生活推广后,消费者对建筑的规划、环境影响以及节能等关注将增加,进而影响建筑行业的发展。在分析低碳生活对建筑影响的基础上,提出了包括人才培养、政策支持和扩大宣传的多级支持发展建议。 相似文献
902.
溶解氧对好氧颗粒污泥影响的研究进展 总被引:1,自引:0,他引:1
好氧颗粒污泥技术是一种新颖废水处理技术。溶解氧(DO)是好氧颗粒污泥形成和稳定运行的一个重要参数。好氧颗粒污泥需要的曝气量大,能耗高。高曝气量带来的高DO浓度不利于氨氮通过SND去除。当DO扩散在颗粒内部受到限制时,颗粒中心形成的厌氧层不利于颗粒污泥的长期稳定运行。本文系统分析了DO浓度对好氧颗粒污泥影响的国内外研究现状,对好氧颗粒污泥中DO浓度这一重要参数的研究进行了总结。研究在低DO浓度下保持好氧颗粒污泥的稳定性有利于降低运行成本,采取合适的方法降低颗粒内部的扩散限制有利于增强颗粒的稳定性能。 相似文献
903.
石油污染土壤原位生物修复的强化实验研究 总被引:2,自引:0,他引:2
为研究添加营养物质和高效降解石油微生物对油污土壤生物修复的作用,通过分层土柱的方法,连续监测了不同条件下不同土层的含水率、石油烃含量、细菌数量及脱氢酶活性。结果表明:添加营养物质同时接种高效微生物可使降解效果明显改善,降解率比在自然条件下提高近50%,而单纯添加营养物质不接种高效微生物可使降解率比在自然条件下提高约25%。降解初期,上层土壤降解效果较好,而到中后期,中下层降解效果好于上层。微生物数量和脱氢酶活性与石油降解率之间存在良好的相关性,脱氢酶活性比微生物数量更能反映修复过程中微生物的存活状态。添加营养物质和高效降解石油微生物对油污土壤原位生物修复具有强化作用。 相似文献
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906.
Ram B. Jain 《毒物与环境化学》2016,98(1):137-148
National Health and Nutrition Examination Survey (NHANES) uses two tobacco use surveillance questionnaires. One is administered during an at-home interview (HI) and the other, during an examination session at a mobile examination center (MEC). NHANES data for the years 1999–2012 were used to evaluate the consistency of responses to tobacco surveillance questions in HI and MEC interview. In addition, accuracy of self-reported smoking status was evaluated. Of those who reported to be daily cigarette smokers during HI, 18.7% reported to be either some-day smokers or nonsmokers during MEC interview. Of those who reported to be some-day cigarette smokers during HI, 22.1% reported to be daily smokers and 17.5% reported to be nonsmokers. Also, 4.1% of those who reported to be nonsmokers during HI reported to be either daily or some-day smokers during MEC interview. Using serum cotinine measurements taken during MEC interview, 27.1% were found to be smokers and 72.9% were found to be nonsmokers. In general, a moderate to high agreement, as measured by the κ statistic, was found between the self-reported responses to tobacco use questions during the home and MEC interviews as well as between smoking statuses based on self-reported and serum cotinine measurements. 相似文献
907.
Olanrewaju Lawal 《Journal of Land Use Science》2016,11(2):222-235
The incorporation of land use (LU) data with socioeconomic data is a main issue in modelling. This is as a result of difference in data model and scale. This study proposed and tested the change–pattern approach, which allows the incorporation of these data sets in modelling LU change. Focusing on LU dynamics for a selected part of the Thames Gateway within the City of London, the approach tested two different methods of input selection for the modelling operations. Variables selected from these two methods serve as inputs into several neural networks tested in order to identify the direction of change for each of the LU types within the study area. The result shows that direction of LU change across the study area could be identified when spatial morphology of the area and socioeconomic variables are considered. Some classes of change could be identified fairly accurately using landscape metrics indicating level of fragmentation, extent of LU patches, shape complexity of LU patches in combination with some socioeconomic variables. 相似文献
908.
Patrick Meyfroidt 《Journal of Land Use Science》2016,11(5):501-522
Research into land and social-ecological systems science could benefit from improved clarity in the terminology used for causal analysis and a structured way to make causal inferences. Here I identify two aspects of causality, i.e. causal effects and causal mechanisms, and discuss explanation in historical sciences. I then propose definitions for the major terms used for causal relations, including driver, (spatial) determinant, location and contextual factor, proximate and underlying factors. Finally, I discuss the contribution of various operational approaches, including time series and counterfactual approaches for assessing causal effects and process-tracing approaches for establishing causal mechanisms. Having a coherent concept of causality, agreeing on a precise vocabulary and harnessing our tools with the clear purpose of establishing both causal effects and causal mechanisms should strengthen causal explanations for single cases, for drawing policy-relevant lessons and for theoretical development in relation to land and, more broadly, social-ecological systems processes. 相似文献
909.
Magdalini Soupioni Kyriaki Vlachou Alexandra Psarologou Argyro Bekatorou 《毒物与环境化学》2016,98(10):1191-1199
AbstractThe extent to which selected ethanol and lactic acid production bioprocesses contribute to whey waste abatement was examined. Alcoholic fermentation of whey was carried out by kefir cells immobilized on grape stalks, delignified cellulosic materials, or brewer's spent grains. Lactic acid fermentation was also performed by free kefir cells with or without addition of brewer's spent grains as promoting material. Since whey fermentation rate is affected by the lactose uptake rate, 14C-labeled lactose was used to study the fermentation ability of kefir. The highest reductions in biochemical oxygen demand and chemical oxygen demand of whey, about 68% and 52%, respectively, were achieved by lactic acid fermentation in 6 h at 37 °C and pH 5.5, in the presence of 120 g brewer's spent grains. Additionally, at the same conditions, the highest 14C-labeled lactose uptake rate by kefir and consequently the highest alcoholic fermentation rate were also recorded. However, greater reductions in biochemical oxygen demand and chemical oxygen demand of whey are required prior to final disposal. 相似文献
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