排序方式: 共有51条查询结果,搜索用时 19 毫秒
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选择2台重型柴油车发动机,在测功机台架上复现其在中国典型道路工况下的运行过程,并测取发动机的外特性曲线、特征转速和ETC(European Transient Cycle,欧洲瞬态循环)做功量;在此基础上,基于美国和欧洲2种典型的重型在用车符合性检测方法,即NTE(Not To Exceed,区域达标)法和AWM(Averaging Window Method,窗口平均值法),对比研究了这2种方法对中国重型柴油车典型道路工况的适应性. 结果发现:NTE法对在重庆国道高速公路下运行的重型柴油车工况具有较好的覆盖性,但对北京通州的公交车运行工况的覆盖性较差;改变NTE事件的采样时间准则和控制区域定义,对NOx比排放的数值影响不大. AWM能够利用全部的道路工况数据,但是由于怠速工况的存在,使得用该方法计算出的平均NOx比排放值比NTE法得出的数值偏高;而基于ETC循环做功量的窗口平均NOx比排放值具有较为合理的离散度. 相似文献
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Corrective measures based on pressure control strategies for CO2 geological storage in deep aquifers
A prerequisite to the wide deployment at an industrial scale of CO2 geological storage is demonstrating that potential risks can be efficiently managed. Corrective measures in case of significant irregularities, such as CO2 leakage, are hence required as advocated by the recent European directive on Carbon Capture and Storage operations. In this regard, the objective of the present paper is to investigate four different corrective measures aiming at controlling the overpressure induced by the injection operations in the reservoir: stopping the CO2 injection and relying on the natural pressure recovery in the reservoir; extracting the stored CO2 at the injection well; extracting brine at a distant well while stopping the CO2 injection, and extracting at a distant well without stopping the CO2 injection. The efficiency of the measures is assessed using multi-phase fluid flow numerical simulations. The application case is the deep carbonate aquifer of the Dogger geological unit in the Paris Basin. A comparative study between the four corrective measures is then carried using a cost-benefit approach. Results show that an efficient overpressure reduction can be achieved by simply shutting-in the well. The overpressure reduction can be significantly accelerated by means of fluid extraction but the adverse consequences are the associated higher costs of the intervention operations. 相似文献
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本文阐述了福建福人木业有限公司(原福州人造板厂)始终坚持“以人为本,安全第一”的思想,建立健全企业安全生产管理体系、安全生产科技文化体系、安全生产经费投入体系等,使企业连续15年实现安全生产,保障企业经济在新形势下可持续发展的措施。 相似文献
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农村居民点整理是促进节约集约用地的重要举措。以抽样调查获取的424份调查问卷为基础,构建了包括农户个人特征、家庭经济状况、家庭住房状况、其它因素在内的Logistic模型,分析了农户居民点整理意愿及影响因素。研究显示:(1)研究区域农村居民点整理意愿不强烈,仅41.5%的农户愿意居民点整理,其主要原因是担心生活成本增加、失去生活保障以及恋土情结等;(2)农户住房套数、与邻居血缘关系、家庭承包经营耕地面积、家庭收入、农户职业类型等都是影响农村居民点整理意愿的主要因素,其中家庭住房套数越多、收入越高、与邻居血缘关系越远的农户整理意愿越强烈,而年龄越大、家庭人口越多、以农业为主的农户则越不愿意整理搬迁;(3)为有效推进居民点整理工作,应切实从农民利益角度出发,努力提高拆迁补偿标准,建立健全社会保障机制,同时加大农村土地制度改革探索 相似文献
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The application of a micro-characterization protocol coupled with a balance approach has allowed the relevant monitoring of a phosphation process for fly ash produced by municipal solid waste incineration. The three main steps of this process consist in removing the salts (chlorides, sulfates) by dissolution at basic pH, phosphation of the residue to trap metals, and its calcination to destroy dioxin-like compounds. The chemical and mineralogical balances compiled on the samples after each step of the process validate these main objectives and highlight the wide phosphorus distribution throughout the sample during the phosphation process, as well as the formation of apatite-type crystallized phosphates. During calcination, the increase in the proportion of crystallized phosphates apatite and whitlockite is largely attributable to the presence of an available calcium source, corresponding to the calcite formed during washing. The metals Pb and Zn, initially distributed in the silicate and carbonate phases, are broadly redistributed in the phosphate neoformations after carbonate dissolution, thus guaranteeing a more permanent stabilization. 相似文献
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金佛山岩溶环境与经济开发对策 总被引:1,自引:1,他引:1
岩溶环境是一种缺土、缺水、富钙的极不稳定极其脆弱的生态环境,本文分析了金佛山岩溶环境的形成,探讨了该区现有的资源优势及其岩溶生态环境的脆弱性对经济发展的滞后作用,并针对该区存在的资源优势和环境劣势,提出了相应的经济开发措施,指出金佛山经济开发不能以牺牲环境保护和生态建设为代价,必须把它们放到与经济开放并重的位置。 相似文献
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纵向塞曼恒温平台石墨炉原子吸收法测定土壤,底质中镉和砷 总被引:5,自引:3,他引:5
为准确测定土壤中低含量元素镉和砷,研究了集恒温平台石墨炉(STPF)一体的纵向塞曼效应背景校正,最大功率升温,钯作基体改进剂和吸收峰面积积分的最新分析方法。方法测定结果,镉和砷的检测限(3σ)分别为35×10-13g和54×10-11g;相对标准差(n=6)分别为41%~52%和26%~45%;回收率分别为865%~109%和912%~105% 相似文献
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贵州春旱短期气候预测信号及预测模型研究 总被引:6,自引:1,他引:5
本文分析研究了贵州春旱的大气环流异常特征,寻找确定了贵州春早的6个短期气候预测信号,并在此基础上以1957~1996年作为样本年代建立了春旱短期气候预测模型.预测模型经1997~2000年为期4年的独立试报,取得了良好效果. 相似文献