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461.
ε-聚赖氨酸生产废菌体对六价铬吸附影响的研究 总被引:6,自引:5,他引:1
以ε-聚赖氨酸(ε-PL)发酵生产废菌体小白链霉菌(Streptomyces albulus)PD-1为研究对象,探讨了其对吸附Cr(Ⅵ)的影响.实验过程中,对预处理方式、pH、初始Cr(Ⅵ)浓度、吸附时间和温度等因素进行了考察.结果表明,HCl预处理的菌体具有较好的吸附能力,Cr(Ⅵ)的吸附增加率达到22.7%,最佳pH为2.0左右,温度对Cr(Ⅵ)的吸附影响不大.实验过程中分别采取Langmuir和Freundlich 2种吸附等温模型对实验数据进行了拟合,得到2个模型的线性相关系数R2分别为0.979 4和0.979 8,这表明吸附过程中既存在单层吸附同时也存在复杂的多层吸附,小白链霉菌对Cr(Ⅵ)的最大理论吸附量为23.92mg.g-1.通过傅里叶变换红外光谱分析,酰胺基和羟基等基团在吸附过程中起主要作用. 相似文献
462.
天然藻类吸附重金属的研究 总被引:1,自引:0,他引:1
传统的重金属废水处理技术存在耗能高、运行成本高及存在二次污染的问题等诸多劣势;而天然海藻由于其来源广、产量大,在处理重金属废水方面存在较多的优点。介绍了藻类处理重金属离子的研究背景、现状,阐述了藻类处理重金属的优点、机理,重点介绍了海藻处理废水过程中的各种影响因素,并对海藻处理废水的应用前景进行了展望。 相似文献
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465.
河套灌区的主体为后套平原,总土地面积为1万平方公里,主要为黄河冲积平原。由于化肥、农药的大量使用,致使河套地区地表水体和地下水氮、磷普遍超标。本文针对河套面源污染问题,提出了几点防治措施。 相似文献
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467.
地震安全社区建设是先进有效的灾害预防模式和载体,是增强社会应急管理能力的重要途径。本文通过对石家庄市建设地震安全社区的经验和做法的分析,对地震安全社区建设提出了"十个一"的建议。 相似文献
468.
采用Sato单次散射模型,利用大柴旦台数字地震资料,研究了大柴旦震群序列尾波Qc值在流逝时间窗长60~90 s时间内的变化特征,计算频率从3 Hz至18 Hz,得到Qc值随频率的变化关系:Qc(f)=(72±19.9)f0.93±0.08。计算结果反映出大柴旦地震余震序列的尾波Qc值较低,说明大柴旦震源区属于构造运动较为活跃的地区,这与大柴旦地质结构特征相符。 相似文献
469.
A framework for analyzing climate change adaptations as actions 总被引:1,自引:0,他引:1
Klaus Eisenack Rebecca Stecker 《Mitigation and Adaptation Strategies for Global Change》2012,17(3):243-260
Developing generalized theories about adaptation to climate change requires common concepts to map different adaptation situations.
The paper aims to contribute to this endeavor by presenting a novel framework that conceptualizes adaptations to climate change
as actions. The framework is intended to systematically analyze the actor relations involved in adaptations and the barriers
to their implementation. By combining established scientific action theories with terminology from the Intergovernmental Panel
on Climate Change (IPCC) in an innovative way, it can be used to clarify the notion of adaptation used in adaptation assessments.
The framework’s potential is illustrated by a case study on cooling water management in the river Rhine catchment and by the
elucidation of some prominent concepts in adaptation research. We show that by framing adaptations as actions, the purpose
of adaptations and how they tend to connect up in means-ends-chains becomes crucial. Actors can take different functional
roles as exposure unit, operator and receptor of adaptation. A mismatch of these roles can lead to barriers to adaptation,
of which we deduce four types: complex actor relations, missing operators, missing means and unemployed means. The case study
yields a complex bundle of adaptations, and shows that the potential barriers involved are quite diverse. There is thus no
blueprint solution. Although we identify entry points for adaptation, the analysis leads to a skeptical conclusion for adapting
cooling water management in the whole Rhine catchment. 相似文献
470.
Ellen M. Douglas Paul H. Kirshen Michael Paolisso Chris Watson Jack Wiggin Ashley Enrici Matthias Ruth 《Mitigation and Adaptation Strategies for Global Change》2012,17(5):537-562
We explored the possible future impacts of increased coastal flooding due to sea level rise and the potential adaptation responses
of two urban, environmental justice communities in the metropolitan Boston area of Massachusetts. East Boston is predominantly
a residential area with some industrial and commercial activities, particularly along the coastal fringe. Everett, a city
to the north of Boston, has a diversified industrial and commercial base. While these two communities have similar socioeconomic
characteristics, they differ substantially in the extent to which residents would be impacted by increased coastal flooding.
In East Boston, a large portion of residents would be flooded, while in Everett, it is the commercial/industrial districts
that are primarily vulnerable. Through a series of workshops with residents in each community, we found that the target populations
do not have an adaptation perspective or knowledge of any resources that could assist them in this challenge. Furthermore,
they do not feel included in the planning processes within their communities. However, a common incentive for both communities
was an intense commitment to their communities and an eagerness to learn more and become actively engaged in decisions regarding
climate change adaptation. The lessons that can be applied to other studies include 1) images are powerful tools in communicating
concepts, 2) understanding existing cultural knowledge and values in adaptation planning is essential to the planning process
and 3) engaging local residents at the beginning of the process can create important educational opportunities and develop
trust and consensus that is necessary for moving from concept to implementation. 相似文献