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931.
932.
In this work, continuous removal of Malachite Green from aqueous solution by adsorption was investigated using a laboratory scale fixed-bed column packed with binary solid mixture of seashell powder (SSP) and eggshell powder (ESP). The effects of initial dye concentration, feed flow rate, bed height, and the SSP?:?ESP ratio in the binary solid mixture on the breakthrough characteristics were studied. The breakthrough time decreased with increase in the flow rate and the initial dye concentration. The breakthrough time also varied greatly with change in bed height. The breakthrough time increased from 17.2?h to 34.5?h with increase in bed height from 6?cm to 12?cm. The breakthrough time was significantly affected by the change in the SSP?:?ESP ratio in the binary mixture. The breakthrough time decreased with increase in the SSP ratio in the binary mixture. In order to determine the column kinetic parameters, three different column kinetic models, namely Adams–Bohart, Bed Depth Service Time (BDST), and Yoon–Nelson models were fitted to the dynamic flow experimental data. The BDST model showed good agreement with the experimental results at all the process parameters studied. Results suggest that this novel approach of simultaneous utilization of adsorbents can be adopted for the treatment of dye-bearing effluents. 相似文献
933.
Severe soil erosion in the upper reaches of the Yangtze River and the middle reaches of the Yellow River is a serious environmental problem in western China. In order to control this soil erosion, the national government implemented the Grain for Green Program (GGP) in Sichuan Province (in the upper reaches of the Yangtze River) and Shaanxi Province (in the middle reaches of the Yellow River) in 1999. To evaluate the effects of the GGP on soil erosion, the present study investigated the relationships between annual precipitation and three parameters, annual runoff, sediment concentration, and sediment discharge, for these rivers. As the area covered by the GGP increased, sediment concentration and sediment discharge both decreased, and the correlation with the GGP area was much stronger than the correlation with annual precipitation. Therefore, China's GGP appears to be controlling soil erosion in the upper reaches of the Yangtze River and the middle reaches of the Yellow River. 相似文献
934.
ABSTRACTThis paper interprets aspects of the implementation of environmental education in a Higher Education Institution, situated in a developing country, to promote Education for Sustainable Development (ESD). The paper will allow educators to categorise the multiplicity of ESD programmes and projects in higher education institutions, determine their limitations and acceptability, and benefit from the theoretical framework of affective learning in designing new ESD interventions. The paper will also provide an overview of the processes required to establish ESD in developing and developed countries. This paper will further help universities to develop a better understanding of how integration of the three components of sustainable development – economic development, social development and environmental protection – can be incorporated in higher education. The paper explores the challenges for planning the implementation of ESD in an education faculty, outlining the potential lessons learned that could assist in improving ESD efforts in Faculties of Education. 相似文献
935.
936.
We integrate new challenges to thinking about resource markets and sustainable resource use policies in a general framework. The challenges, emerging from six papers that JEEM publishes in a special issue, are (i) demand uncertainty and stockpiling, (ii) international trade and resource dependence, (iii) deforestation, and (iv) intertemporal effects of climate change policies (“Green Paradox”). We discuss new insights and results on these issues by fitting them into the Hotelling model of non-renewable resource depletion. 相似文献
937.
用改进的TRAP法测定树木端粒酶活性 总被引:1,自引:0,他引:1
TRAP法是一种常用的测定端粒酶活性的方法,但并不太适合测定木本植物的端粒酶活性.因此以油松针叶为实验材料,对TRAP法进行改进.参照前人的研究通过对比实验证明,在端粒酶提取过程中将PEG8000加入上清液,可获得高效的端粒酶.在此基础上,对PCR先导引选择TS、模板浓度选择100 ng,最终获得油松针叶高质量的端粒酶PCR产物.应用SYBR Green I替代银染液对电泳凝胶进行染色,获得条带清晰、重复性好的电泳结果.通过对油松针叶、银杏叶片、胡杨愈伤组织、沙冬青悬浮细胞等4种木本植物实验材料进行测定,证明该改进的技术体系可能是适合于木本植物端粒酶活性测定的稳定的、灵敏度高的可行方法.图5表1参17 相似文献
938.
We investigated the effect of financial incentives on performance in a professional organization. Whereas agency theory treats tangible rewards such as money as a potentially powerful motivator for improving performance, the professional control perspective posits that the motivational effects of financial incentives will depend on the intended recipients attitudes toward the incentives relative to their professional values. The study setting was a large network of physician practices that adopted a financial incentive program to improve physician performance in the management of diabetic patients. Consistent with agency theory, performance did improve following the introduction of the incentive. However, consistent with the professional control perspective, physicians' psychologically based attitudes toward the incentive program regarding its impact on their own work autonomy and the importance of the performance goals moderated the effect of the incentive on performance. Study findings indicate that agency theory and professional control are complementary theoretical perspectives for understanding how professionals will respond to the imposition of performance‐related financial incentives. In terms of practice, pay‐for‐performance programs aimed at professional organizations should be designed to take into account the values and goals of an organization's professionals to maximize the effect of financial incentives on performance. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
939.
基于EFQM的建筑企业安全投入绩效评估SEM 总被引:1,自引:1,他引:0
为解决目前我国建筑业安全生产事故频发,安全投入不足及其绩效产出低下的现状,通过探索性因子分析,从建筑企业安全投入22项组成内容中提炼出6项要素;借鉴欧洲质量卓越(EFQM)模型,建立建筑企业安全投入绩效评估结构方程模型(SEM),实证分析安全投入构成要素之间的复杂交互影响关系:领导分别对人员、资源设施、政策战略具有正向直接影响;人员与资源受到政策战略的正向直接影响,并对生产过程与事故损失产生正向直接与间接影响。因此,在加强领导投入以提升整体安全投入绩效的前提下,提高政策战略对于人员、资源与设施的约束性,将最终保障安全生产与减少事故损失。 相似文献
940.
航空人为差错事故/事件分析(ECAR)模型研究 总被引:2,自引:0,他引:2
为深入研究航空人为差错事故/事件的影响因素,以人为差错相关理论为基础,对比分析几种典型的人为差错分析模型;通过借鉴ECCAIRS分析框架,并在基元事件分析(EEAM)逻辑和CCAR396部的分类方法基础上,构建航空人为差错事故/事件分析(ECAR)模型,它从事件层、描述层、原因层和组织因素与改进建议层,分析航空事故和不安全事件的人为差错。此外,还将组织因素概念引入该模型。 相似文献