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硝酸钙在底泥修复中的作用机理及 总被引：11，自引：0，他引：11
受污染底泥的修复已经成为水环境修复中的重要组成部分，在底泥中注入硝酸钙则是近十多年来发展起来的一种污染底泥原位处理技术。全面分析了硝酸钙在底泥修复中去除有机物、抑制磷的释放以及消除水体黑臭现象的机理，并介绍了这一技术在国内外的研究和应用状况。研究成果表明：在底泥中注入硝酸钙的技术已从实验室和中试研究阶段发展到了实际的工程动作阶段，并且在有机物PAHS的降解和硫化物的去除方面已经得到了很好的效果。 相似文献
76.
Yongtang Jin 《Irrigation and Drainage Systems》1988,2(2):173-184
The largescale Dujiangyan Irrigation System has had a long history. Built some 2200 years ago, it still operates smoothly today. Two major causes for the obvious profits it has provided are:Firstly, Yuzui (a bifurcation pier), Feishayan (a sand outlet and spillway) and Baopingkou (a diversion intake for the general trunk canal), the three main head-works were built in accordance with the terrain and topography of the river and appropriately arranged, thus successfully solving the problem of sand discharge and flood control. Consequently the task of gravity diversion could be fulfilled over a long period.Secondly, there is a special management and maintenance system, which is made up of a technical and an administrative department. The former is in charge of the maintenance and drawing-up of flood control and water consuming plans. The latter is responsible to mobilize and organize farmers which benefit from the system to carry out related plans and tasks. The most apparent characteristics of management is that many farmers are organized to participate in the management of this irrigation system. At present, techniques like remote control and telemetery have been adopted. Also experiments on management automation and optimization of water allocation are being conducted. 相似文献
77.
煤水浆(CWM)是一种新型的正在开发的可工业化的石油代用燃料。而将煤水浆用于柴油机则处于试验阶段。流变特性是煤水浆性质判定的主要依据之一。本文将就下列三方面对超细煤木浆与柴油组成的混合液(用作柴油机燃料)的流变特性进行分析:(1)流变模型和流变参量;(2)超细煤水浆与柴油的最佳混合比;(3)触变性。 相似文献
78.
The quality of service provided by the provincial Irrigation Department (DGI) to the Water Users Associations (UA), and subsequently by the UA's to the related water users, is based on the provincial water law. The intended volume of water being delivered per considered period further depends on the water availability and on the (crop irrigation) water requirements. The Service Level (SL) compares the intended water supply with the water supply that would be required to supply the entire irrigable area with sufficient water. As soon as the intended water delivery pattern is set, the measured actual delivery can be assessed against the intention. Several performance indicators are used in this context. Based on the assessment of the Water Delivery Performance Ratio and the Overall Consumed Ratio recommendations are made on changes which can be made to improve water use and reduce problems of waterlogging. 相似文献
79.
This paper reports on laboratory research on the sediment passagecapability through long-throated flumes and broad-crested weirs withwhich the Froude number in the approach channel does not exceed 0.6over a distance of about 20 times the water depth upstream of thestructure. Design rules are given for any combination of flume or weirin combination with any channel. 相似文献
80.
为解决能源和环境两大难题,使发动机工作在稀薄燃烧区,而稀薄燃烧技术的关键是发动机空燃比的控制;采用先进的计算机控制技术使发动机在最佳稀薄空燃比下工作,有效改善发动机动力性、燃油经济性、降低尾气污染。 相似文献