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生物淋滤对尾矿的重金属污染处理的效果已经得到了广泛的认可.在对酸性尾矿中的土著氧化硫硫杆菌以及氧化亚铁硫杆菌进行分离以及加富培养的基础上,分别运用单一菌种以及混合菌种对尾矿样本进行淋滤处理.通过12 d的淋滤实验,实验室结果表明,分离出的氧化亚铁硫杆菌以及氧化硫硫杆菌等土著微生物具有较高的利用价值.同时实验表明,在采用适当菌种的前提下,尾矿中重金属的溶解率都得到了不同程度的提高:土著氧化亚铁硫杆菌对Zn的淋滤效果最好,达到了98.12%;对于Cu的淋滤,土著氧化亚铁硫杆菌与土著氧化硫硫杆菌的混合菌种的效果最好,达到88.75%. 相似文献
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利用中国30个省区的数据检验了中国经济相容于巴拉萨-萨缪尔森效应的程度,结果表明:各省区的相对劳动生产率的差异与相对价格的关系符合巴拉萨-萨缪尔森效应理论所描述的特征。对各省区的相对劳动生产率与相对价格进行逐个的协整检验,结果表明:有23个省区的数据符合理论所预示,这也从一个角度提供了各省区通货膨胀率长期存在差异的解释。进一步研究发现,生产率的差异与各省区的实际汇率之间存在较弱的长期协整关系。 相似文献
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在传统的“统治”观念中,政府是公共产品、公共服务、社会福利的唯一提供者,而现代“治理”理念认为,公共治理的主体是多元的,NPO也是重要的治理主体。综观各个国家公共领域的发展,建立合作伙伴关系已经成为各国的共识。当前,NPO的迅速崛起和全球化已经被看成是影响未来全球发展的主要因素之一。在我国,构建政府与NPO之间的合作伙伴关系同样是政府与NPO关系发展的未来走向,两者合作伙伴关系的构建离不开政府主导作用的发挥,也离不开NPO的充分发展和社会的支持。 相似文献
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ZHANG Xiao rong 《保鲜与加工》2008,8(5):1-3
从贺兰山紫蘑菇分布、分类、形态特征及生理学特性等方面进行了介绍,并结合国内开发利用现状与出现的问题对贺兰山紫蘑菇的发展前景进行展望。 相似文献
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HUANG Lei chang ZHANG Zhi guo HUANG Chun yan SUN Xu cai WANG Xiang rong 《保鲜与加工》2008,(4):27-32
We discussed the trends and challenges of rapid urbanization for modern landscape from a development viewpoint. We analyzed the problems of modern landscape in P. R. China. Based on ecological principles, we proposed a corresponding eco-thinking model composing eco-thinking of vision, culture, environmental protection and public participation. We carried out a case study of the south entrance of Tongniuling Scenic Spot in Dalian. We constructed diverse scenarios according to the leading factors selected by factor analysis. We assessed them with the Delphi method and public anticipation. The priority rating was, in order, scenario number 2 (48.3%), number 1 (30.5%) and number 3 (15.7%). Scenario number 2 was the best for its prominent visual image, typical culture presentation, weaker disturbance and reasonable cost. Scenario numbers 1 and 3 took culture and environment as leading factors, respectively. The cost of the former was low while the latter was high. Our work indicates that the eco-thinking model, as a brand-new thinking for modern landscape, is feasible. 相似文献
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The Monte Carlo Finite Element Method is superior to other methods when it is used to analyze the reliability of the initial support of a highway tunnel. A correct reliability index could be collected when an adequate number of samples is selected because the failure probabilities of engineering structures are usually very small. The amount of sampling could sharply decrease by using the dual sampling method. During the comparison, the supporting role exaggeration of the line element, which is used in the FEM model to simulate the initial lining and rock bolt, was found by FEM simulation. The lining element reaction forces which were greater than usual were reported in FEM analysis results. Deeply Buried Tunnel Reliability Analysis was developed on the platform of ANSYS. 相似文献
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A forecasting model for logistics demand was presented to overcome the limitations of single goal forecasts of logistics demand and forecast data complexity. Based on the forecasting evaluation index and pretreatment of rough set theory, a multi input and multi output wavelet network (MMWNN) model for forecasting multi element regional logistics demand was studied. The network configuration was confirmed using the stepwise checkout and iterative gradient descent methods. After rough set reduction, the evaluation index was used to forecast the multi element regional logistics demand. The results of the numerical example indicate the feasibility and effectiveness of the model. 相似文献
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In order to improve the convergence rate of genetic algorithms based on edge detection, a novel edge detection method based on a good point set genetic algorithm (GGA) was proposed. The proposed method designed the crossover operation with the theory of good point set in which the progeny inherits the common genes of the parents which represent its family so as to improve the convergence rate of the genetic algorithm. Furthermore, before the algorithm was used for edge detection, the feature space of the image grey level was transformed into the feature space of the fuzzy entropy. Dissimilarity enhancement processing next was applied to the image by using a fuzzy entropy theory to filter the non edge pixels so as to reduce the scale of the solution domain. This approach offered another efficient way to improve the convergence rate. Experimental results show the proposed algorithm performs very well in terms of convergence rate. The detected edge image is well localized, thin, and robustly resistant to noise. 相似文献