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排序方式: 共有113条查询结果,搜索用时 62 毫秒
71.
渗滤液的同质与异质回灌技术   总被引:4,自引:0,他引:4  
根据承受回灌封场单元的稳定化程度、渗滤液与回灌载体的同质或异质关系,提出了渗滤液在其母体垃圾体中回灌的同质回灌概念和渗滤液在非母体垃圾中回灌的异质回灌概念.在异质回灌中,渗滤液可以引到稳定化程度较高的非母体填埋单元回灌,从而明显提高渗滤液中污染物的去除效果.同质回灌中,渗滤液与回灌垃圾载体性质相似,处理效果较差,其回灌意义基本上是自然蒸发减量化.  相似文献   
72.
通过冲裁间隙对冲裁断面、冲裁力的影响 ,提出合理冲裁间隙  相似文献   
73.
陡坡带构造演化史研究对断陷湖盆具有重要意义,平衡剖面技术在面积(体积)守恒的基础上为恢复构造演化史提供了一种科学合理的技术方法。通过对东濮凹陷兰聊陡坡带进行平衡剖面法构造演化史恢复,再现了兰聊断层的活动规律及其对东濮断陷湖盆发展演化的控制作用,明确了东濮凹陷早第三纪层序地层发育特征、坡折带类型及其对砂砾岩扇体的控制作用,指出了隐蔽油气藏发育的有利层段和分布的有利地区。  相似文献   
74.
基于北京市空气质量监测点获取的空气污染物浓度数据,通过遗传算法搜索径向基人工神经网络的最优隐含层神经元数目和扩展常数,构建了耦合径向基人工神经网络算法与遗传算法的预测模型,预测北京市未来一天24h平均PM2.5质量浓度.结果表明,预测精度与泛化性能良好.该模型不需要输入气象和地理位置信息等数据,具有依赖变量少、预测精度高(R2达0.75)和运算效率高等特征,并可以通过训练样本的驱动,使自身不断优化调整.该模型预测效果可以通过扩展输入特征、增加训练样本量等方法进一步提升,可对多种时空情境下的城市空气污染进行高效率且精确的预测.  相似文献   
75.
开发利用蔗茅野生种质资源的思考   总被引:3,自引:0,他引:3  
综述了国内外甘蔗种质资源的研究现状,对开发利用蔗茅野生种质提出了一些研究思路.目前,生产上使用的甘蔗品种是由甘蔗属内的3~5个种杂交培育而来,其亲缘关系较近,遗传基础日益狭窄.因此,开发利用具有优异遗传性状的甘蔗种质资源,综合应用新技术、新方法,以扩大甘蔗遗传多样性、提高甘蔗育种效率是解决这一问题的重要途径.  相似文献   
76.
DPIV图象的诊断方法研究   总被引:3,自引:0,他引:3  
数字粒子图象测速技术已在国内外各个实验方向得到广泛的重视和应用,但应用的关键就在于它的诊断方法。本文介绍了DPIV图象诊断方法中最常用的互相关法。并发展了传统互相关算法,然后对互相关法进行平移和旋转的标定,以确定其可行性和可靠性。最后应用于重力作用下水射流的实验。  相似文献   
77.
This study advances the limited research on work alignment and work engagement by investigating how perceived alignment of job tasks and organizational strategic priorities (strategic alignment) influences work engagement. Measures of job control and work social support were also included to enable comparisons between strategic alignment and other well‐established job resources. A total of 1011 employees of an Australian state police service responded to three electronic, self‐report surveys. A reciprocal model was assessed over three waves of data, with varying time lags: 18 (Time 1 to Time 2), 12 (Time 2 to Time 3), and 30 months (Time 1 to Time 3). Longitudinal, reciprocal relationships were observed for work engagement and job control, strategic alignment, and colleague support. Work engagement also predicted supervisor support over time (reverse effect). This study demonstrated that, in addition to job resources, perceived alignment of job tasks and organizational priorities plays an important role in maintaining high levels of work engagement over time. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
78.
Burst disks are often used as the highest level of defense against over pressure. 36 knife blade burst disks were spent to test their steadfastness and reliability. Half of the burst disks were subjected to stress similar to normal use in a plant. They showed no sign of degradation compared to the unstressed disks. However many disks failed to burst at the specified pressure and none opened with the specified cross section. These parameters are essential for dimensioning pressure relief equipment.  相似文献   
79.
This paper investigates how internally displaced persons (IDPs) in Batticaloa, Sri Lanka, financed their first year of displacement. We conducted extensive fieldwork in August 2007 in numerous welfare centres in Batticaloa that have received persons displaced from the Mutur divisional secretariat (DS) in the Trincomalee district. The sample was selected from the village of Sampur in Mutur DS. The displaced from Sampur are of Tamil origin and our findings reveal certain coping strategies that may be particular to this community, including the selling or mortgaging of gold jewellery to address the effects of displacement. We found that the IDPs in this region rely heavily on jewellery and other forms of savings to ensure their survival. There is also strong evidence to support the critically important coping role played by livelihoods. These coping strategies have enabled the IDP households in the present sample to live marginally above the poverty line.  相似文献   
80.
Natural weathering processes are significant mechanisms that noticeably affect the fundamental nature of incineration ash residues. To provide a greater understanding of these processes, a MSWI (mono)landfill site in the north east of the US was selected as the target for systematic investigation of the natural weathering of bottom ash residues. Samples of various ages were collected from locations A (1 yr), B (10 yrs), C (13-14 yrs) and D (20 yrs) of the landfill in 2009. We investigated the phase transformation of the collected bottom ash particles, neoformation processes as well as the behavior and distribution of certain heavy metals (Cu, Pb, Zn, Ni, and Cr) in the neoformed phases using optical microscopy, SEM-EDX, and bulk examinations. Key findings: at the preliminary stage, the waste metallic particles (Al, Fe, and Cu) and unstable minerals such as lime, portlandite, ettringite and hydrocalumite convert to oxide and hydroxide (hydrate) phases, calcite, alumina gel and gypsum. At the intermediate stage, the decomposition of melt products including magnetite spinels and metallic inclusions is triggered due to the partial dissolution of the melt glass. At the longer time horizon it is possible to track the breakdown of the glass phase, the extensive formation of calcite and anhydrite, Al-hydrates and more stable Fe-hydrates all through the older ash deposits. Among the dominant secondary phases, we propose the following order based on their direct metal uptake capacity: Fe-hydrates>Al-hydrates>calcite. Calcite was found to be the least effective phase for the direct sorption of heavy metals. Based on overall findings, a model is proposed that demonstrates the general trend of ash weathering in the landfill.  相似文献   
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