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981.
Municipal solid waste management (MSWM) in China warrants particular attention as China has become the largest MSW generator in the world and the total amount of MSW it produces continues to increase. In recent years, central and local governments have made great efforts to improve MSWM in China. New regulations and policies have been issued, urban infrastructure has been improved, and commercialization and international cooperation have been encouraged. Considering these developments, an overview is necessary to analyze the current state as well as new opportunities and challenges regarding MSWM in China. This paper shows that since the late 1990s, the amount of MSW collected has been largely decoupled from economic growth and incineration has become an increasingly widespread treatment method for MSW. We identify and discuss four major challenges and barriers related to China’s MSWM, and propose an integrated management framework to improve the overall eco-efficiency of MSWM. 相似文献
982.
Jae E. Yang Earl O. Skogley Mahtab Ahmad Sang Soo Lee Yong Sik Ok 《Environmental geochemistry and health》2013,35(6):715-725
The resin capsule system (RCS) was tested as a means of providing data on the presence and forms of volatile hydrocarbons. Results indicated that resin capsules provided data showing sensitivity to soil variables (texture and moisture content) and time. The objectives of this paper are to evaluate the RCS methodology and to determine whether carbonaceous resin capsules provide results that can be described by fundamental chemical partitioning and kinetic principles. Findings revealed a significant relationship between quantities of benzene, toluene, ethylbenzene, and xylene adsorbed on the capsule and quantities partitioned into the vapor phase. Kinetic evaluation indicated that the vapor adsorption by the resin capsule is regulated by diffusion processes. No verification of rate-limiting processes was possible due to limitations imposed by the experimental design, but it appears that during early stages, adsorption rate was limited by vapor diffusion through the soil. The resin capsule data also reflected differences that would be expected due to properties of the organic liquids present. These results provide further evidence that the RCS could be developed to suggest direct in situ monitoring to reveal quantities and nature of organic substances in soils. 相似文献
983.
对旧建筑物拆除,诸如墙体、基础、砖石建筑物、地板、油罐等容器、铜结构和特殊结构建筑物的拆除中的一般安全技术措施、拆除设施的设置、警告装置、安全装置,均作了较具体而明确的要求;对机械法拆除和爆破法拆除两种拆除方法中的安全技术要求,也有简要论述。 相似文献
984.
985.
Hongzhi Wang Qihui Shao Rendong Li Mingjie Song Yong Zhou 《Environmental monitoring and assessment》2013,185(12):10521-10536
The prosperity of farmers is closely tied to governmental policies. The Jianghan Plain is an important region for commodity grains, cotton and edible oil for China. The trajectories of land use and land cover change (LUCC) of the study area from 1995 to 2010 were studied based on the LUCC database of the Chinese Academy of Sciences. The LUCC was characterised by a continuous decrease of arable land and continuous increase of waters and construction land. The LUCC was obviously concurrent with the implementation of related national policies. The transition to construction land was ever well controlled by ‘Notice regarding the further strengthening of land management and arable land protection’ promulgated in 1997. However, it flourished again with the ‘Rise of Central China Strategy’ taking effect since 2006. The transition of construction land to others reflects an uncommon trend, which must be strengthened with the strict implementation of the overall plan, which imposes a limited acreage quota of construction land to each district. The policies were quite contradictory to the transition of waters. LUCC related to waters is most active, which was driven by both natural forces and national policies. Just after the devastating flood of 1998, the state council of China put forward the Green Policy to govern the major rivers. As to the study area, it is mainly to ‘push over dykes to let flood through and return farmland to lakes’. In 2004, the Grain Direct Subsidy Policy was implemented, which, along with the surge in the price of rice, resulted in a strengthening trend of conversion of ponds to paddy fields. 相似文献
986.
Yong Ju Choi Young-Jin Kim Kyoungphile Nam 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2197-2202
This study investigated the ability of a saponin-based microbubble suspension to enhance aerobic biodegradation of phenanthrene by subsurface delivery. As the microbubble suspension flowed through a sand column pressure buildup and release was repeatedly observed, which delivered oxygen to the less permeable regions. Burkholderia cepacia RPH1, a phenanthrene-degrading bacterium, was mainly transported in a suspended form in the microbubble suspension. When three pore volumes of the microbubble suspension containing B. cepacia RPH1 was introduced into a column contaminated with phenanthrene (100 mg/kg), the oxygen content declined to 5% from an initial value of 20% within 5 days and correspondingly, 34.4% of initial phenanthrene was removed in 8 days. The addition of two further three pore volumes enhanced the biodegradation efficiency by a factor of 2.2. Our data suggest that a saponin-based microbubble suspension could be a potential carrier for enhancing the aerobic biodegradation under an oxygen-limiting environment. 相似文献
987.
JaeYoon Lee SungJun Park Cheonghoon Lee Kyuseon Cho Yong Seok Jeong Young-Mog Kim Kwon-Sam Park Jong Duck Choi Yongsik Sin GwangPyo Ko 《Food and environmental virology》2020,12(3):240-249
Human and animal feces are important sources of various types of microbial contamination in water. Especially, enteric viruses, the major agents of waterbo 相似文献
988.
冲击地压是煤岩体突然遭遇动力破坏,释放大量能量的灾害动力现象,可摧毁顶板、巷道、引发其它矿井灾害,造成人员伤亡.在冲击地压的预测、预报中,煤矿企业安装了不同公司的独立子系统,但这些系统侧重点不同,检测到的信息是不完整、不全面、不精确甚至有时是互相矛盾的.为此,需要运用信息融合技术把各个系统进行动态优化组合.根据矿山压力显现的基本规律性和各变量之间的内在联系,应用D-S证据融合理论,把微震监测系统、综采压力系统、电磁辐射系统、钻孔应力系统,包括钻屑法等环节获得的信息进行数据融合,其融合的结果能更好的解释矿山压力与岩层顶板运动发展的规律性,提高了冲击地压预测预警的准确率,改善了系统的可靠性,对于提前掌握顶底板运动变化的趋势和规律,指导安全生产与决策具有—定的指导意义. 相似文献
989.
基于高光谱遥感的沿海河口无机氮浓度空间分布特征解译 总被引:1,自引:0,他引:1
利用39组样本的野外实测光谱结合Hyperion影像资料,建立了高悬沙含量沿海河口可溶性无机氮(dissolved inorganic nitrogen,DIN)的高光谱定量遥感解译模型,实现DIN浓度空间分布规律的遥感反演及动态监测.研究发现,当悬沙浓度0.1kg/m3时,DIN浓度与悬沙含量之间呈显著的倒数相关关系,相关系数R2为0.617.据此首先将重采样处理后的野外实测光谱与同步DIN浓度数据进行统计相关分析,筛选出2个对DIN浓度变化敏感的波段,中心波长分别为630nm和804nm;然后利用波段反射率R804和R630计算出仿泥沙遥感参数因子R804×R630/(R804-R630),建立其与实测DIN浓度的非线性遥感模型,29组建模样本和10组检验样本的相关系数R2分别为0.746和0.67,DIN浓度平均绝对误差分别为109.07μg/L和147.58μg/L.将该非线性遥感模型应用于Hyperion影像,获得了射阳河口DIN浓度的空间分布特征,DIN浓度的变化范围为52~513μg/L.可以看出,在以悬沙为主要悬浮物的沿海河口,遥感解译得到的DIN浓度扩散趋势与潮流的运动以及悬沙的运移规律密切相关.因此,在无需了解水动力状况的条件下,高光谱遥感是对DIN浓度进行动态监测的有效手段. 相似文献
990.
中国松嫩草原羊草植硅体对全球变暖和氮沉降模拟的响应研究 总被引:3,自引:1,他引:2
在松嫩草原应用红外线增温和人工施氮的方法对羊草群落模拟全球变暖和氮沉降,提取羊草中的植硅体,分析探讨植硅体的形态及数量变化规律.羊草中的植硅体可以划分为4个大类和12个亚类,以及较小的植硅体碎片,其中帽型植硅体含量高达70%.尖顶帽型和平顶帽型植硅体与刺帽型植硅体可能有不同的发育机制,并且尖型植硅体对施氮更为敏感;与对照相比,增温处理对羊草植硅体的发育有促进作用(长宽增加0.1~2.6μm),而施氮处理则有一定的抑制作用(长宽减小0.1~1.4μm),增温和施氮交叉作用,则施氮对羊草植硅体发育表现出的抑制作用明显减弱;施氮处理中出现其他处理中未见到的空心棒型(占棒型总量的46%),而且除棒型、帽型、尖型以外的植硅体含量增加到10%,从而推测,对于以羊草为优势植物的松嫩草原,施氮的影响可能要强于增温,如果两者同时作用,增温能在一定程度上缓解施氮的影响.实验中的羊草植硅体对模拟全球变化很敏感,说明植硅体对环境因子的改变很敏感,其作为古环境的代用指标应是可靠的. 相似文献