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91.
固定污染源监测断面的选择对流量测定的影响   总被引:2,自引:0,他引:2  
监测断面的选择在废气污染源监测中起着相当重要的作用 ,在无法找到完全符合技术规范要求的监测断面时 ,以前常将监测断面选择在砖砌烟囱上的方法。通过实验 ,否定了该方法应用于测定废气流量较小的污染源的可行性 ,提出了应用于测定废气流量较小的污染源时 ,较为成熟的监测断面选择方案。  相似文献   
92.
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   
93.
94.
Abstract

This study describes the elimination of zearalenone concentrations in vitro using two new polymeric forms of cross‐linked polyvinylpyrrolidone (cryogels of cross‐linked PVP). Adsorption of zearalenone was studied under isothermal conditions and simulating pH of intestinal environment. A Freundlich isotherm was used to describe the adsorption data obtained. The results showed significant decrease of zearalenone concentrations, ranging from 33.5–66.2 % per 25 mg of polymer. Adsorption capacity (k) was estimated to be higher than that of previously tested adsorbents, including crospovidone. The data indicate the need to investigate structure peculiarities in order to improve mycotoxin deactivation procedures using PVP derivatives.  相似文献   
95.
The high conservational value of the lichen-rich vegetation and landscape of the marine foreland Ørkenen on the isle of Anholt is treated from a Danish as well as a European perspective. The sensitivity of the lichen-rich vegetation to physical disturbance is emphasized. The impact of invasive species such asPinus mugo as well as the effect of atmospheric deposition of nutrients on the heaths at Anholt is described. Considerations related to the development of a management plan for Ørkenen are presented.  相似文献   
96.
GM(1,1)模型群在黄河水质预测中的应用研究   总被引:5,自引:0,他引:5  
灰色预测对统计数据较少问题可以进行预测,一般3-4个数据就可以建模,由于建模序列长短不同,会得到不同的预测方程,即对实际问题发展趋势某种程度的把握.实际预测时若能将不同的预测结果综合考虑进去,效果更佳.介绍了GM(1,1)模型建立的方法与步骤,并依据黄河潼关断面过去10年(1996-2005年)水质状况,利用GM(1,1)模型群预测了未来7年(2006-2012年)的水质发展状况.  相似文献   
97.
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   
98.
《组织行为杂志》2017,38(1):45-67
This paper examines the role of employees' future time perspective (FTP) in the association between human resource management (HRM) systems and work‐related attitudes. Drawing on social exchange theory, signaling theory, and affective events theory, we hypothesize HRM systems' indirect effects on individual‐level job satisfaction and affective organizational commitment as mediated by FTP. The results of this multilevel study, comprising 913 employees of 76 business units, provide evidence that HRM systems have (i) direct effects on employees' FTP and (ii) indirect effects on job satisfaction and organizational commitment via FTP. In addition, three HRM bundles' (i.e., knowledge, skills, and abilities enhancing; motivation enhancing; and opportunity enhancing) corresponding indirect effects are explored. We discuss the results, theoretical contributions, and practical implications of the study, as well as future research directions. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
99.
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   
100.
旱作垅种(小麦)沟盖(玉米)地膜带田优于目前推广的沟种(小麦)垅盖(玉米)带田种植形式。在作物共生期相互调水作用更趋合理,平衡了小麦、玉米不同生育阶段对水分的供需矛盾,作物的生态条件更加适宜,群体结构更加协调,提高了作物的生产量,前者比后者增产90%~125%。  相似文献   
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