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战争不仅浪费大量的人力、物力、财力,破坏人类生存的社会环境,而且也破坏人类生存的自然环境.战争对生态环境的影响是多方面的,本文介绍了战争对生态环境的直接影响与间接影响,对环境要素的直接影响分为对水体、对生物、对大气、对土壤的影响;间接影响可分为常规武器、生物化学武器、核武器对生态环境的影响. 相似文献
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2007年6月5日是第36个世界环境日。当前,党中央、国务院高度重视污染减排工作。作为一个负责任的发展中大国,中国以“污染减排与环境友好型社会”为主题,积极回应世界环境日的全球行动,具有重要的现实意义和深远的战略意义。与此同时,环保总局对外发布了2006年中国环境状况,对去年我国的总体环境现状和环境保护工作取得的成就进行了全面的回顾。 相似文献
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Michael C. Newman Philip M. Dixon Brian B. Looney John E. Pinder 《Journal of the American Water Resources Association》1989,25(4):905-916
ABSTRACT: Left-censoring of data sets complicates subsequent statistical analyses. Generally, substitution or deletion methods provide poor estimates of the mean and variance of censored samples. These substitution and deletion methods include the use of values above the detection limit (DL) only, or substitution of 0, DL/2 or the DL for the below DL values during the calculation of mean and variance. A variety of statistical methods provides better estimators for different types of distributions and censoring. Maximum likelihood and order statistics methods compare favorably to the substitution or deletion methods. Selected statistical methods applicable to left-censoring of environmental data sets are reviewed with the purpose of demonstrating the use of these statistical methods for coping with Type I (and Type II) left-censoring of normally and log-normally distributed environmental data sets. A PC program (UNCENSOR) is presented that implements these statistical methods. Problems associated with data sets with multiple DLs are discussed relative to censoring methods for life and fatigue tests as recently applied to water quality data sets. 相似文献
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纳米二氧化钛粉体的制备及对染料脱色的研究 总被引:1,自引:0,他引:1
以钛酸四丁酯为原料,采用溶胶-凝胶法、水热沉淀法、水解法制备了纳米二氧化钛粉体。经XRD对三种方法制得粉体进行了表征,讨论了三种方法的优缺点。以水解法制得二氧化钛粉对六种染料进行了脱色研究,结果表明其有良好的光催化脱色性能。 相似文献
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Ecotechnological methods have been employed by developed countries like the United States of America, Europe, Australia and
Japan in the restoration of their degraded freshwater ecosystems. These methods according to literature sources, in many cases
have produced the desired results in these countries where they have been implemented. This article is aimed at providing
an overview on aspects of available ecotechnological methods employed in the reduction of eutrophication and acidification
and in Lake Ecosystem restoration in general. Ecotechnological methods offer great opportunities for developing countries
with tropical or subtropical climates due to their cost-effectiveness. The efficacy and potential limitations of the various
methods in their respective restorative approach is also reported in this article. 相似文献
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本文主要介绍了汽车内饰件感官测试——气味性测试的常规测试方法,对比归纳了国内车企对气味性测试方法的制定依据及参考要素,总结出了比较理想的气味性测试方法。 相似文献
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Mark S. Reed Anil Graves Norman Dandy Helena Posthumus Klaus Hubacek Joe Morris Christina Prell Claire H. Quinn Lindsay C. Stringer 《Journal of environmental management》2009
Stakeholder analysis means many things to different people. Various methods and approaches have been developed in different fields for different purposes, leading to confusion over the concept and practice of stakeholder analysis. This paper asks how and why stakeholder analysis should be conducted for participatory natural resource management research. This is achieved by reviewing the development of stakeholder analysis in business management, development and natural resource management. The normative and instrumental theoretical basis for stakeholder analysis is discussed, and a stakeholder analysis typology is proposed. This consists of methods for: i) identifying stakeholders; ii) differentiating between and categorising stakeholders; and iii) investigating relationships between stakeholders. The range of methods that can be used to carry out each type of analysis is reviewed. These methods and approaches are then illustrated through a series of case studies funded through the Rural Economy and Land Use (RELU) programme. These case studies show the wide range of participatory and non-participatory methods that can be used, and discuss some of the challenges and limitations of existing methods for stakeholder analysis. The case studies also propose new tools and combinations of methods that can more effectively identify and categorise stakeholders and help understand their inter-relationships. 相似文献
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人类活动排放的大量温室气体已经造成多种不利影响,为缓解这些不利影响,已有多个国家提出了碳中和目标。碳中和评估与预测预估是实现碳中和目标的科学基础,准确估算碳排放量和碳去除量是进行碳中和评估的关键,可以帮助决策者制定减排和增汇政策。本文梳理了碳排放量和碳去除量的估算方法以及预测预估方法的原理和特点,以期为准确评估碳中和现状以及预测预估未来情景下实现碳中和目标的可能性和路径提供方法论参考。碳排放量的估算方法可以分为用于支撑碳交易市场的碳排放核算方法、面向消费侧碳排放的估算方法和基于因素分解法的碳排放计量方法三大类;前两类方法主要用于历史碳排放量的盘点,第三类方法可用于碳排放量的预估。陆地生态系统碳去除量估算方法可以分为统计模型法、机理模型法和遥感模型法三大类;第一类方法应用最早但估算结果较粗糙,第二类方法模型应用最多但估算结果存在较大的不确定性,第三类方法观测范围大但缺乏预测预估能力。近年来,模型分析法在碳中和评估和预测预估上得到越来越广泛的应用。 相似文献