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1.
Francisco M. Baena-Moreno Mónica Rodríguez-Galán Fernando Vega Luis F. Vilches Benito Navarrete 《International Journal of Green Energy》2019,16(5):401-412
Biomethane production through biogas upgrading is a promising renewable energy for some industries which could be part of the equilibrium needed with fossil fuels consumption to achieve a sustainable society. This paper presents a comprehensive list of biogas upgrading technologies focused on carbon dioxide removal as well as recent advances reported by researcher with wide expertise in this topic. Additionally, an extensive costs–performance comparison among the technologies studied is discussed. Among the different alternatives, chemical scrubbing stood out to achieve high biomethane purities while cryogenic technologies proved to be effective against methane losses. Regarding the different costs, water scrubbing and membrane separation seem to be the most affordable techniques. 相似文献
2.
日本国土开发利用及对我国的启示 总被引:1,自引:0,他引:1
日本在战后经历了经济高速增长,工业化和城市化快速推进的发展历程,其间土地利用在结构、规模、价格、集约利用等方面发生了巨大变动。本文全面分析了二战之后,日本在经济高速增长、产业结构巨大变动、城市化迅速推进的发展过程中.农业用地、工业用地和城市用地在结构、规模、价格、集约利用程度等方面的特征;日本政府针对经济发展和土地利用的变动和影响。制订的一系列规划调整措施和政策法规体系。通过以上分析,探讨日本在有限的土地资源条件下实现经济高速增长的原因、途径和措施,以及对我国的启示。 相似文献
3.
村级水资源的管理与利用研究--来自南方四个村的案例分析 总被引:1,自引:0,他引:1
农村水资源及其相关设施的改革需要更多了解村和户层次上的现实状况和机制安排。以避免改革扭曲和失败。通过对湖北和广西共四个村的村委会、关键知情人及120个农户的调查。在村和农户两个层次上描述水资源及其相关设施的管理与利用,尤其是在干旱年份村和户所采取的策略。并深入分析了农村村级水资源管理与利用的制度安排与问题。得出的结论是。追求水利管理效率的市场化改革需要考虑干旱的威胁,要有基于风险的制度设计和法律保障。 相似文献
4.
5.
The impact of refugees on the health status and health services of host communities: Compounding bad with worse? 总被引:1,自引:0,他引:1
Dick B 《Disasters》1985,9(4):259-269
Although there have been a number of recent developments in our understanding of refugee health problems that have influenced policies and action, the effects of refugees on the health status and services of host communities remain relatively neglected. This article sets out to explain why this is an important issue with implications for policy, planning surveillance and evaluation, training and research.
The first sections outline some of the problems facing host governments and communities in Africa and discuss the changing rhetoric between the first and second International Conferences for Assistance to Refugees in Africa. A number of possible ways in which refugees could affect the individual, agent and environmental causes of disease are considered, as are the characteristics of the refugees, the host communities and the response which may all modify this impact.
Policy implications of the impact of the refugees, both negative and positive, are discussed, and detailed consideration is given to the pros and cons of integrated and parallel approaches to health care provision. The need to monitor carefully the health status and services of host communities is emphasized and recommendations are made for this and other essential developments relating to training and research. 相似文献
The first sections outline some of the problems facing host governments and communities in Africa and discuss the changing rhetoric between the first and second International Conferences for Assistance to Refugees in Africa. A number of possible ways in which refugees could affect the individual, agent and environmental causes of disease are considered, as are the characteristics of the refugees, the host communities and the response which may all modify this impact.
Policy implications of the impact of the refugees, both negative and positive, are discussed, and detailed consideration is given to the pros and cons of integrated and parallel approaches to health care provision. The need to monitor carefully the health status and services of host communities is emphasized and recommendations are made for this and other essential developments relating to training and research. 相似文献
6.
通过现场采样和室内培养实验分析了藻类植物的生长状况和细胞结合态磷对磷酸盐浓度的响应.现场调查结果发现,在水华区域藻类植物的细胞磷库分布特点与非水华区域明显不同.室内培养结果发现,中肋骨条藻和东海原甲藻的最大磷酸盐吸收速率为7.71,2.39μmol/(L·d),最大比生长率分别为0.517,0.262d-1,磷酸盐吸收同化率为5.9×10-8,4.7×10-7μmol/cell,前者具有更快的磷酸盐吸收能力,更高的比生长率和较低的磷酸盐吸收同化率.2种藻细胞内结合态磷通常占细胞总磷库的50%以上,是细胞磷库主要存在形式.中肋骨条藻种群可以通过藻细胞数量增长来吸收环境中的磷源,而东海原甲藻则会优先满足细胞自身的磷储存后进行细胞增殖.在高浓度磷环境中,东海原甲藻种群的细胞不同结合态磷的质量浓度会达到饱和.磷匮乏时,中肋骨条藻和东海原甲藻的细胞内结合态磷的质量浓度与零时刻相比分别降低了45%和66%,前者明显低于后者.培养过程中,中肋骨条藻单个细胞的细胞表面吸附态磷库(95%)比细胞内磷库(50%)的降低幅度更大,东海原甲藻则与之相反. 相似文献
7.
京津冀及周边地区水泥工业大气污染控制分析 总被引:1,自引:0,他引:1
以京津冀及周边地区水泥工业为研究对象,基于产排污系数法,建立了水泥工业主要大气污染物排放计算方法,对2016年该地区水泥工业主要大气污染物排放控制水平进行了分析.结果表明:京津冀及周边地区2016年水泥工业SO2、NOx、PM(有组织)排放量分别达到3.2×104t、23.9×104t、9.7×104t,较2015年分别减少24.1%、18.2%、27.2%,各项污染物大幅下降.水泥工业PM无组织排放量占PM总排放量的45.4%,仍需要采取集中收集的方式加强治理.山东、河南是水泥工业SO2、NOx、PM、PM10、PM2.5重点排放来源,应通过化解过剩产能降低污染排放.从各工艺来看,新型干法工艺应考虑采用高效脱氮脱硫技术、协同处置技术、高效大型袋式除尘技术等新技术,进一步降低各项污染物的排放量;粉磨站也需进一步提高污染治理水平. 相似文献
8.
针对新疆物理监测工作(包括噪声监测、振动监测、辐射监测等)现状及环保监测系统物理监测的人员、仪器、能力等情况,分析了物理监测工作存在的不足,并对今后更好的开展物理监测工作提出建设性意见。 相似文献
9.
During the summers of 1991–1994, the Environmental Monitoringand Assessment Program (EMAP) sampled 344 lakes throughout thenortheastern United States using a proportional stratified sampling design based on lake size. Approximately one-quarter ofthe 344 lakes were sampled each year (4 years) for totalphosphorus to determine the proportion (and associated95% confidence intervals) of the northeast lake population 1ha (11,076 ± 1,699 lakes) that was in oligotrophic,mesotrophic, eutrophic, or heupereutropic (4 classes) conditionaccording to the total phosphorus criteria of the North AmericaLake Manegement Society. Estimates for the second, third, andfourth yr were developed as cumulative of the previous yrsamples and the current yr samples for the northeast as a wholeand for each of its three ecoregions (4 regions). New confidence intervals were computed for each cumulative yrcondition estimate. This produced a total (4 years × 4classes × 4 regions) of 64 cumulative yr tropic conditionestimates. Confidence intervals for 21% of these estimates didnot shorten with increased sample size. This phenomena raisedquestions about the accuracy of estimates based on cumulativesampling procedures. We explain why and how the phenomenon comesabout with both straight random and proportional randomsampling. Further, we present an example of the effects thisphenomenon has on lake tropic state condition estimates in thenortheastern United States. 相似文献
10.
通过对新疆著名旅游城市吐鲁番的空气环境、水环境、声环境、景观生态环境等环境质量存在的问题进行分析,针对性地提出了相应的环保对策及建议,为吐鲁番市的环境保护工作提供参考。 相似文献