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951.
原油对草原植被的影响   总被引:4,自引:1,他引:4  
为了定量说明落地原油对大庆地区草原植被的影响,选择了四种植物群落进行浇原油试验,浇油厚度为0.2、0.4、0.8cm,浇油时间为秋、春、夏。试验结果表明原油对植物个体的影响因原油量、季节和植物种类的不同而不同,随原油量的增加影响增大。  相似文献   
952.
Lead contamination at shooting range soils is of great environmental concern. This study focused on weathering of lead bullets and its effect on the environment at five outdoor shooting ranges in Florida, USA. Soil, plant, and water samples were collected from the ranges and analyzed for total Pb and/or toxicity characteristic leaching procedure (TCLP) Pb. Selected bullet and berm soil samples were mineralogically analyzed with X-ray diffraction and scanning electron microscopy. Hydrocerussite [Pb3(CO3)2(OH)2] was found in both the weathered crusts and berm soils in the shooting ranges with alkaline soil pH. For those shooting ranges with acidic soil pH, hydrocerussite, cerussite (PbCO3), and small amount of massicot (PbO) were predominantly present in the weathered crusts, but no lead carbonate mineral was found in the soils. However, hydroxypyromorphite [(Pb10(PO4)6(OH)2] was formed in a P-rich acidic soil, indicating that hydroxypyromorphite can be a stable mineral in P-rich shooting range soil. Total Pb and TCLP Pb in the soils from all five shooting ranges were significantly elevated with the highest total Pb concentration of 1.27 to 4.84% (w/w) in berm soils. Lead concentrations in most sampled soils exceeded the USEPA's critical level of 400 mg Pb kg(-1) soil. Lead was not detected in subsurface soils in most ranges except for one, where elevated Pb up to 522 mg kg(-1) was observed in the subsurface, possibly due to enhanced solubilization of organic Pb complexes at alkaline soil pH. Elevated total Pb concentrations in bermudagrass [Cynodon dactylon (L.) Pers.] (up to 806 mg kg(-1) in the aboveground parts) and in surface water (up to 289 microg L(-1)) were observed in some ranges. Ranges with high P content or high cation exchange capacity showed lower Pb mobility. Our research clearly demonstrates the importance of properly managing shooting ranges to minimize adverse effects of Pb on the environment.  相似文献   
953.
姚廷伸  高健 《四川环境》1990,9(2):17-25
本文综述了近十年来水中重要有机污柒物—酚类化合物的分离富集技术,以及色谱法(GC法和HPLC法)分析。  相似文献   
954.
造纸白泥烟气脱硫技术的工业应用   总被引:1,自引:0,他引:1  
曹友洪 《环境保护科学》2009,35(4):13-15,33
介绍了晨呜集团齐河板纸有限公司4×75t/h燃煤锅炉采用造纸白泥烟气脱硫工艺,着重阐述了SO2吸收系统工作原理和流程,测试了不同pH吸收液和过氧系数对脱硫效率的影响,分析了Na^+浓度、Cl-、F-浓度对脱硫系统的影响,并与石灰石石膏对比做简单的技术经济比较,为相似装置的设计提供参考。  相似文献   
955.
介绍了拟动力抗震试验方法的特点和原理,指出误差控制是拟动力试验成败的关键。对计算误差和系统误差等误差主要来源进行了分析,模拟了试验误差传递和积累过程,并从数值积分、试验设备、试验控制等方面对抑制试验误差的方法和措施进行了探讨。  相似文献   
956.
目前,国家对彩票业越来越重视,政府为满足特定的社会公共需求而发行的彩票已成为一种重要筹资手段,而近些年来中国彩票业的迅速发展,也为环保彩票的发行提供了有利的借鉴.文章通过分析环保彩票在中国的经济基础及生态环境背景下发行的客观条件,回顾近些年来有关环保彩票的学术文献,以及期间各种关于环保彩票的发行呼吁与尝试,指出了国家在环保彩票方面的探索进程.并结合中国的实际情况,提供对策建议,为早日在国内发行环保彩票做好铺垫.  相似文献   
957.
电化学法用于微污染水脱氮处理实验   总被引:3,自引:0,他引:3  
采用电化学方法,以轻度污染的温榆河河水为研究对象,考察了电化学方法对微污染地表水中氨氮的去除效果,探讨极板间距、反应时间以及板间电压对氨氮去除的影响。研究表明:反应时间为10min,板间距为1.0cm,板间电压为11V时,该方法对去除微污染水中氨氮有较好的处理效果,对氨氮的去除由原水的8~36mg/L降至2.4~11mg/L,去除率能达到70%以上,同时总氮的去除与氨氮去除呈现良好的相关性。  相似文献   
958.
三江平原小叶章湿地系统硫的输入及输出动态   总被引:2,自引:1,他引:1  
以三江平原小叶章(Calamagrostis angutifolia)湿地系统为研究对象,应用野外原位观测法研究了小叶章湿地系统硫的大气沉降输入及其输出规律.结果表明大气湿沉降中硫的月均含量变化明显,其原因主要与人类活动、降水强度及频次有关;硫沉降量具有明显的月变化特征,经估算三江平原小叶章湿地硫的年沉降总量(以S计)为113 mg·m-2·a·-1.小叶章湿地H2S、COS的排放通量均具有明显的季节和日变化规律.H2S和COS的平均释放通量(以S计)分别为O.34 μg·m-2·h-1和-0.29μg·m-2·h-1;小叶章湿地系统在生长季向大气排放H2S的量(以S计)为1.42 mg·m-2,从大气吸收COS的量(以S计)为1.83 mg·m-2.小叶章湿地系统硫的输入量远高于硫输出量,其差值为113.41 mg.m-2·a-1,这表明硫在小叶章湿地系统中处于累积状态,湿地存在潜在的酸化趋势.  相似文献   
959.
Prior to independence, Central Asian countries were closely interconnected through the regional management incorporating water, energy, and food sectors. This approach, supported by the central government of Union of Soviet Socialist Republics (USSR), functioned effectively — meeting the needs of both upstream and downstream countries. However, after independence, Central Asian countries started prioritizing their own economic development policies without due account to regional concerns such as joint use of water resources, leading to instability. In this study, the case of Syrdarya basin was investigated to show how such strategies create tension in the region, since primary focus is given to national interests, without consideration for regional problems. To address this issue, an integrated approach to incorporating water, energy, and agriculture is needed. It is suggested that a single sector approach on water alone does not lead to stability, and a multi-sectoral approach is necessary to ensure sustainable development. Countries sharing benefits from the river have to be responsible for costs of operation and maintenance of the water facilities.  相似文献   
960.

Carbon footprint (CF) research has attained tremendous popularity for improving the climate environment purposes. In particular, current energy use has been identified as the main cause of climate change. CF plays an irreplaceable role in managing energy use, reducing gas emissions, and improving climate change. The objective of this study was to review studies that have developed CF and to perform a bibliometric analysis using two key terms: “climate change” and “energy use”. From bibliometric analysis using CiteSpace and VOSviewer, it was possible to establish a knowledge map of cooperative network structure and research evolution. We are aiming to reveal the main logical chain of CF research leading to climate change, to make up for the lack of current literature, and provide research inspiration for researchers. The research findings mainly focus on four aspects. First, the relevant research began in 2008 and is in a state of continuous rise. Second, due to the law of research development and the prominence of practical problems, related research has experienced a stage from conceptual methods to specific problems. Third, China and the USA assume an important role in which international cooperation is the overall trend. Fourth, related research can be divided into CF algorithm research, ecological environment management research, and specific cross-industry fields. In addition, possible opportunities for change in related research are explored. It is also suggested that the integration of CF with other footprints, when energy use and environmental change are fully considered, may become an important future research trend by providing a more comprehensive environmental impact.

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