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排序方式: 共有826条查询结果,搜索用时 62 毫秒
821.
好氧颗粒活性污泥的培养及理化特性研究 总被引:88,自引:20,他引:68
研究厌氧-好氧交替工艺中好氧颗粒活性污泥的培养和理化特性,在普通好氧曝气条件下,反应顺内培养出了好氧颗粒活性污泥,颗粒直径0.5-1.5mm,比重1.007左右,含水率97-98%,MLSS4.04-6.88%g/L,SV120-45ml/g,一般约30ml/g,颗粒污泥受阻沉降层的均匀沉降速度vs约2.15cm/min,临界浓度时沉降速度值v2约0.35cmin,颗粒污泥的耗氧速率OURW1.2 相似文献
822.
超滤膜-生物反应器处理生活污水及其水力学研究 总被引:25,自引:3,他引:22
用超滤膜-生物反应器进行处理生活污水试验并研究其水力学行为。结果表明,当HRT为5h、SRT为30d、膜面流速为4m/s膜流量为75L/(m^2·h)时,试验出水水质优于建设部生活杂用水水质标准CJ25.1-89,可直接回用。 相似文献
823.
在政策支持和实际需求的驱动下,可能会导致县级地区垃圾焚烧项目迅速增多,且带来潜在的环境监管压力和环境社会风险,需要给予持续的特别关注,并对地方做好环境监管和风险管控的指导。本文基于全国精细化的生活垃圾焚烧处理设施、生活垃圾产生量、网络舆情等数据,通过构建泰森多边形等空间分析方法进行了焚烧处理设施的服务范围识别及负荷率计算,通过自然语言处理技术进行了关于生活垃圾焚烧处理设施的情感分析。在此基础上,基于焚烧处理设施的负荷率和负面舆情比例,对全国31个省份环境社会风险进行定量的评估分析并提出对策建议,一是平衡解决“缺口大”和“吃不饱”问题,合理规划布局县级地区生活垃圾焚烧处理设施;二是聚焦负面舆情高发领域、区域,积极防范县级地区生活垃圾焚烧处理设施环境社会风险。 相似文献
824.
William J. Smith Claudio S. Quilodrán Michał T. Jezierski Ashley T. Sendell-Price Sonya M. Clegg 《Conservation biology》2022,36(3):e13867
Domestic animals have immense economic, cultural, and practical value and have played pivotal roles in the development of human civilization. Many domesticates have, among their wild relatives, undomesticated forms representative of their ancestors. Resurgent interest in these ancestral forms has highlighted the unclear genetic status of many, and some are threatened with extinction by hybridization with domestic conspecifics. We considered the contemporary status of these ancestral forms relative to their scientific, practical, and ecological importance; the varied impacts of wild–domestic hybridization; and the challenges and potential resolutions involved in conservation efforts. Identifying and conserving ancestral forms, particularly with respect to disentangling patterns of gene flow from domesticates, is complex because of the lack of available genomic and phenotypic baselines. Comparative behavioral, ecological, and genetic studies of ancestral-type, feral, and domestic animals should be prioritized to establish the contemporary status of the former. Such baseline information will be fundamental in ensuring successful conservation efforts. 相似文献
825.
In this study, we suggested a criterion of Korean resource productivity calculation method including its range which is not generalized yet and analyzed its level by reviewing the resource productivity management policies and study trends of the major advanced countries. The material flow indexes that are widely used in major advanced countries, such as the domestic material consumption (DMC), were used to establish the resource productivity calculation method with estimation the domestic resource productivity during 2000–2010. As of 2010, the DMC was 590 million ton, GDP was 1 trillion dollars and DMC-based resource productivity was 1.75 thousand US dollars/ton, which was continuously increased during last ten years with 8.0%, 50.0%, and 38.9%, respectively. This increase tendency was not because of DMC reduction through resource management but because of just large GDP increase. The results of the comparison with other countries indicated that Korea had the lower resource productivity level and also the lower increasing rate than major advanced countries such as the UK and Japan, and required an efficient resource management plan for improvement. Therefore, we finally suggested a Korean resource productivity policy direction to construct its sustainable system for its improvement. 相似文献
826.