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341.
The effect of lead on the sorption of 2,4,6-trichlorophenol (2,4,6-TCP) on soil and peat was investigated using a batch equilibration method. Lead markedly diminished the sorption of 2,4,6-TCP, and 2,4,6-TCP had little effect on lead sorption. Peat was a more effective adsorbent for 2,4,6-TCP than soil. The desorption hysteresis of 2,4,6-TCP verified the presence of high-energy sorption sites. Mechanisms of lead suppression effect on the 2,4,6-TCP sorption included the following: Firstly, lead accelerated the aggregation of colloids, the aggregates covered the surface in part and shrunk the pore sizes of the adsorbents, hence decreased the sorption of 2,4,6-TCP. Secondly, X-ray absorption and Fourier transform infrared spectroscopy study suggested that lead competed with 2,4,6-TCP for carboxylic, phenolic and Si-OH groups of organic matter and clay minerals. Such competition was partly responsible for the overall suppression effect of lead on the sorption of 2,4,6-TCP.  相似文献   
342.
Effects of environmental contamination on plant seasonal development have only rarely been properly documented. Monitoring of leaf growth in mountain birch, Betula pubescens subsp. czerepanovii, around a nickel-copper smelter at Monchegorsk hinted advanced budburst phenology in most polluted sites. However, under laboratory conditions budburst of birch twigs cut in late winter from trees naturally growing around three point polluters (nickel-copper smelter at Monchegorsk, aluminium factory at Kandalaksha, and iron pellet plant at Kostomuksha) showed no relationship with distance from the emission source. In a greenhouse experiment, budburst phenology of mountain birch seedlings grown in unpolluted soil did not depend on seedling origin (from heavily polluted vs. clean sites), whereas seedlings in metal-contaminated soil demonstrated delayed budburst. These results allow to attribute advanced budburst phenology of white birch in severely polluted sites to modified microclimate, rather than to pollution impact on plant physiology or genetics.  相似文献   
343.
Heavy metals in coastal wetland sediments of the Pearl River Estuary, China   总被引:12,自引:0,他引:12  
Sediment quality in coastal wetlands of the Pearl River Estuary was concerned since the wetlands were used for land reclamation, aquaculture and wildlife protection, and meanwhile served as one of the main ultimate sinks for large amount of heavy metals discharged from the rapidly developing Pearl River Delta. Total concentrations of heavy metal, such as Zn, Ni, Cr, Cu, Pb, and Cd, and their chemical speciation were investigated. Results showed that the sediments were significantly contaminated by Cd, Zn and Ni with concentration ranges of 2.79-4.65, 239.4-345.7 and 24.8-122.1mg/kg, respectively. A major portion (34.6-46.8%) of Pb, Cd, and Zn was strongly associated with exchangeable fractions, while Cu, Ni and Cr were predominantly associated with organic fractions, residual, and Fe-Mn oxide. Cd and Zn would be the main potential risk and the sediment quality is no longer meeting the demand of the current wetland utilization strategies.  相似文献   
344.
Cost-effective biosorbents made from the byproducts of agriculture, forest, and related industries, such as barley straw, canola meal, and wood sawdust, have significant water adsorption capacity, showing a great potential for selective water removal from bioalcohols to produce fuel grade products. However, there is a challenge that the biosorbents are not stable when they come in contact with aqueous solution. There are organic carbons released from biosorbents to liquid phase, which needs to be addressed before this technology is applied in the industrial purification of bioalcohols. In this work, raw barley straw representing an abundant group of cellulosic materials in the above-mentioned industries was used as a model material. A methodology of chemical and physical treatment was developed to treat barley straw which successfully enhanced the stability and reduced the total organic carbon release from the material into the aqueous solution. In addition, the pre-treated barley straw biosorbent had significantly increased micropores, and the Brunauer--Emmett--Teller surface area favored by water adsorption compared with raw barley straw. It also had higher water uptake and dynamic water adsorption selectivity. The pre-treated barley straw was able to selectively remove water and generate concentrated ethanol.  相似文献   
345.
河南省云台山景区规划范围内有28个自然村落,部分村落经过历史的积淀而具有典型的地域特征和深厚的文化底蕴,另一部分村落更具现代气息,成为云台山景区内独特的景观旅游资源。在深入系统调查的基础上,对村落的价值特征进行了综合评价,将云台山景区内村落划分为旅游服务性村落、特色保护性村落两种类型。  相似文献   
346.
中国旅游规划与开发是随着中国现代旅游业的发展而逐渐发展起来的.中国现代旅游业发展历史较短,旅游规划发展的历史也较短.近十余年,随着中国旅游业的迅猛发展,旅游规划与开发正朝着法制化、科学化方向迈进,但就目前情况而言,还存在着许多问题,如规划与开发的立法完善、规划的科学性与实际可操作性等,这些问题的解决可借鉴一些发达国家的旅游规划与开发经验.日本现代旅游业发展历史长,它们在旅游规划与开发方面有着许多值得借鉴的经验.  相似文献   
347.
某专用化学品生产企业在内部需求和外部要求的共同作用下启动并完成了第二轮清洁生产审核工作。通过总结第二轮审核工作实践,发现:可从深入总结首轮清洁生产审核工作、重新规划第二轮审核工作内容、选择性完成第二轮审核的平衡建立工作、强化实施清洁生产方案等方面统筹调整第二轮审核工作的工作方式,从而将清洁生产理念持续推进。此外,在持续推进清洁生产审核工作时,需额外关注第二轮审核工作与第一轮审核工作的不同之处,并充分发挥员工积极性以广泛收集合理化建议,为持续推进清洁生产审核工作创造基础条件。  相似文献   
348.
吉林省环保电子政务信息安全制度规划管理探索   总被引:1,自引:1,他引:0  
本文介绍了电子政务信息安全的定义和内涵,通过对吉林省环保电子政务信息安全制度的梳理和优化,以制度建设为手段来提升环境管理水平,实现以环保电子政务为中心,提高行政服务效率同时以制度为保障降低安全风险。  相似文献   
349.
It was the first time that the Intergovernmental Panel on Climate Change(IPCC),which was founded in 1988,regarded climate change as a significant international political problem(O’Brien and Williams 2007).Over the next decades,environmentalist and policy makers have been applying many efficient ways to solve various environmental problems and have gained achievements.With the support of successful cases,this paper will focus on the market-based solutions and discuss its advantages compared with the conventional approach.  相似文献   
350.
目前,我国有关农村居民生活用水的系统研究相当缺乏。对地处上海市浦东快速城市化区域的8个村庄进行随机入户调查。在对调查数据进行整理和统计分析的基础上,系统研究当地农民的生活用水行为和影响因素。研究表明:(1)被访农民普遍认为自来水价格过高。家庭收入水平是决定被访农民对水价态度的主要影响因素。(2)自来水价格主要对农户的洗衣行为产生显著影响。认为自来水价格高的农户更倾向于用井水洗衣。(3)影响农户自来水用水量的显著变量包括:农户家庭常住人口、自来水价格、洗衣水源和洗澡方式。(4)被访农民普遍具有节水意识,但大都局限于“节约使用自来水,减少自来水水费”这个层面。提高农民的水污染控制和水资源保护意识,正确引导其井水抽取和生活污水排放行为,促进农村污水收集和治理项目的普及和正常运行,以及完善地下水资源的保护和管理机制是现阶段当地保障农村生活用水安全的工作重点  相似文献   
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