共查询到19条相似文献,搜索用时 62 毫秒
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王秀丽 《中国环境管理干部学院学报》2012,22(2):48-51
研究了pH值、吸附接触时间、铜离子的初始浓度及活性炭纤维(ACF)的投加量对活性炭纤维吸附Cu2+的影响,并选取了最佳的实验条件。用Langmuir方程和Freundlich方程拟合活性炭纤维对Cu2+吸附等温线,结果表明:活性炭纤维吸附Cu2+更符合Langmuir等温式,其相关系数为0.9995,以单分子层吸附为主。对活性炭纤维改性能明显提高对Cu2+的吸附,其中效果最佳的吸附量从4.8mg/g增加到17.32mg/g,提高了3.6倍。 相似文献
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论我国废物交换存在的问题及对策 总被引:1,自引:0,他引:1
一、废物交换概述“废物交换”思想是正972年由荷兰首先提出并创建了世界上第一家废物交换机构。很快,欧洲、北美等地的许多国家相继接受了这种思想,仅美国、加拿大就成立了320多家废物交换机构,形成了北美废物交换网络,每年召开一次年会。随后,这种废物管理思想又进入了亚洲,日本首先进行了大范围的实践,取得了很大成就。找国是近几年才开始接受这种思想,并得到了国家环保总局的大力宣传和指导。废物交换的原始定义是,“一个企业的废物可以转变成另一企业的原料的过程”。废物交换可分为信息交换型和物质交换型两种。我国虽然接受… 相似文献
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功能纤维处理含铬废水的初步研究 总被引:10,自引:2,他引:8
试验研究筛选了各种离子交换纤维对Cr^3 和Cr^6 的静态和动态吸附性能,试验结果表明所制磺酸型和羧酸型功能纤维对Cr^3 的静态吸附量在25mg/g-45mg/g纤维的范围,动态吸附穿透曲线比相应的树脂好,但穿透点之前出口液中Cr^3 浓度偏高,所制五种碱性功能纤维对Cr^6 的交换吸附量比较高,最高达293mg/g,最佳吸附pH值都在1-2,其中PVA-g-4VP-季铵化纤维比日本树脂吸附量高很多,它还具有很好的动态吸附Cr^6 的效果,穿透点前的铬浓度近乎为零穿透点突跃明显。 相似文献
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1 前言降水中的硫酸根等阴离子在被土壤吸附的同时,土壤中可交换的氢氧根离子就会被置换出来。这一氢氧根离子将会消耗降水中的氢离子,通过对土壤中硫酸根离子的吸咐量的测定,就可以得知以交换性氢氧根为基 相似文献
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采用改性活性炭粉末对用纯净水加氟化钠配制而成的含氟水溶液进行动态电吸附去除实验.研究不同电压、电吸附时间,以及Cl-和SO2-4对氟离子去除的影响,并探讨吸附动力学和吸附方程.实验结果表明:活性炭对氟离子的吸附等温方程符合Freundlich方程,吸附动力学符合一级动力学方程;活性炭对氟离子去除与所施加的电位、吸附时间等因素有关,施加的电位越大,去除效果越好;随着吸附去除时间的延长,氟离子浓度下降趋缓;Cl-对氟离子去除影响很小,而SO2-4对氟离子去除有显著的不利影响. 相似文献
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在日化工业磷酸盐解析方法的基础上,针对污水中各磷酸盐含量特征,对树脂床高度、淋洗液流速和用量等因素作了选择研究,确定了分离污水中各种磷酸盐及测定其含量的条件和步骤。 相似文献
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本文主要针对信号线路交换网络设计中的失效问题展开讨论,对输出信号在传输网络中失效性进行了评估,根据失效评估在设备可靠性设计方面做了相应的考虑。 相似文献
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《Resources Policy》1989,15(2):156-168
The decline of the dollar since February 1985 relative to countries of the industrialized world is a generally welcome development, acting to restore lost competitive advantages to US industry. However, as this paper shows, use of popular exchange rate indices can be a misleading indicator of shifting competitive advantage. The copper industry serves as an interesting illustration. Real exchange rates have not improved for the USA compared to several important copper producing nations, including Canada, Chile, Mexico, Peru, Zaire and Zambia. As this paper shows, region- or even country-specific analysis of real exchange rate movements is necessary to assess supply side factors. 相似文献
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本文综述了20多年来汞在土壤-大气界面间交换的研究现状,包括汞在大气和土壤中的存在形态、大气汞的干湿沉降、土壤汞释放及影响因素的研究,分析其存在的问题,并提出了未来的研究重点。 相似文献
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This paper discusses a method by which individuals working in government, private business, not-for-profit and educational organizations developed a collaborative statewide program involving the exchange of materials from manufacturers, commercial business and not-for-profit organizations in Ohio. 相似文献
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Peter J. Hancock 《Environmental management》2001,29(6):763-781
Active exchanges of water and dissolved material between the stream and groundwater in many porous sand- and gravel-bed rivers create a dynamic ecotone called the hyporheic zone. Because it lies between two heavily exploited freshwater resources—rivers and groundwater—the hyporheic zone is vulnerable to impacts coming to it through both of these habitats. This review focuses on the direct and indirect effects of human activity on ecosystem functions of the hyporheic zone. River regulation, mining, agriculture, urban, and industrial activities all have the potential to impair interstitial bacterial and invertebrate biota and disrupt the hydrological connections between the hyporheic zone and stream, groundwater, riparian, and floodplain ecosystems. Until recently, our scientific ignorance of hyporheic processes has perhaps excused the inclusion of this ecotone in river management policy. However, this no longer is the case as we become increasingly aware of the central role that the hyporheic zone plays in the maintenance of water quality and as a habitat and refuge for fauna. To fully understand the impacts of human activity on the hyporheic zone, river managers need to work with scientists to conduct long-term studies over large stretches of river. River rehabilitation and protection strategies need to prevent the degradation of linkages between the hyporheic zone and surrounding habitats while ensuring that it remains isolated from toxicants. Strategies that prevent anthropogenic restriction of exchanges may include the periodic release of environmental flows to flush silt and reoxygenate sediments, maintenance of riparian buffers, effective land use practices, and suitable groundwater and surface water extraction policies. 相似文献