燃煤锅炉测试过程中运行负荷测定方法探讨

锅炉运行负荷是锅炉监测获得准确数据的重要条件,但实际监测过程中受各种条件制约,许多锅炉房不具备测试的计量条件。通过一些理论经验公式推导出一个简单的计算锅炉负荷的公式,经过验证,该公式计算值与实测值有较好的一致性。     

有害当量为基准的水污染总量收费标准研究

通过建立有害当量概念,着重研究水污染物的计量基准、单位污染物收费值和总量收费计算办法,并结合现行排污收费标准、污染治理费用等加以综合分析,确定了既科学合理、又简便易行的排放水污染物总量收费标准。      

Studies on Barriers for Promotion of Clean Technology in SMEs of China

1 INTRODUCTIONAccording to the definition of SMEs in the TemporaryRegulation of Small and Medium Enterprise in China(2003): SMEs are those enterprises that have either less than2000 employees or 300 million RMB/year sales revenue, or400 million RMB fixed assets. SMEs generally account for99.88% of the total number of manufacturingestablishments in China in 2002, and they contributesignificantly to the social, economic and industrialdevelopment (Su, 2003).However, the majority of t…     

危险废物无害化管理大数据分析应用研究初探

环境质量改善是我国"十三五"期间环保工作的核心,危险废物管理是影响环境质量的重要因素。近年来,我国危险废物污染防治工作在制度建设和能力建设等方面取得积极进展,但仍存在底数不清、减量不足、利用不畅等问题,频发的危险废物非法倾倒和掩埋已成为突发环境事件的重要诱因,严重威胁环境安全和人体健康。严峻的环境形势迫使我国改进传统的危险废物管理方式。文章从危险废物无害化管理现状分析入手,提出构建危险废物无害化管理大数据应用研究平台的建议,实现依靠数据管理、数据决策和预测性分析的构想。     

关于华北科技学院安全工程专业建设的探讨

简要介绍了我国高校安全工程专业的发展历史。重点分析了以华北科技学院开办安全工程专业教育的发展过程 ,指出了安全工程专业建设方面的办学优势和存在问题 ,提出了适应时代发展 ,完善和发展华北科技学院安全工程专业的详细建议 ,供同行参考     

Effects of sample survey design on the accuracy of classification tree models in species distribution models

We evaluated the effects of probabilistic (hereafter DESIGN) and non-probabilistic (PURPOSIVE) sample surveys on resultant classification tree models for predicting the presence of four lichen species in the Pacific Northwest, USA. Models derived from both survey forms were assessed using an independent data set (EVALUATION). Measures of accuracy as gauged by resubstitution rates were similar for each lichen species irrespective of the underlying sample survey form. Cross-validation estimates of prediction accuracies were lower than resubstitution accuracies for all species and both design types, and in all cases were closer to the true prediction accuracies based on the EVALUATION data set. We argue that greater emphasis should be placed on calculating and reporting cross-validation accuracy rates rather than simple resubstitution accuracy rates. Evaluation of the DESIGN and PURPOSIVE tree models on the EVALUATION data set shows significantly lower prediction accuracy for the PURPOSIVE tree models relative to the DESIGN models, indicating that non-probabilistic sample surveys may generate models with limited predictive capability. These differences were consistent across all four lichen species, with 11 of the 12 possible species and sample survey type comparisons having significantly lower accuracy rates. Some differences in accuracy were as large as 50%. The classification tree structures also differed considerably both among and within the modelled species, depending on the sample survey form. Overlap in the predictor variables selected by the DESIGN and PURPOSIVE tree models ranged from only 20% to 38%, indicating the classification trees fit the two evaluated survey forms on different sets of predictor variables. The magnitude of these differences in predictor variables throws doubt on ecological interpretation derived from prediction models based on non-probabilistic sample surveys.     

测空气和废气中甲醇时气相色谱法的改进

空气和废气监测分析方法一书第五章中甲醇的气相色谱分析方法,应该解决采样时间长回收效率低和色谱分离存在在拖尾大水峰三个方面的问题。     

武汉市大气中TSP、SO_2、NO_x、CO的变化规律研究

对武汉市大气中 TSP、SO2 、NOx、CO浓度的日、月、年变化规律以及 TSP、NOx 浓度和车流量之间的关系进行了研究。结果表明 :SO2 浓度与温度之间呈显著性负相关关系 ,NOx 浓度和车流量之间呈显著性正相关关系 ,TSP与 NOx、CO浓度的变化趋势一致 ,机动车尾气烟尘及行驶引起的扬尘 ,将是 TSP的主要来源     

渤海湾风暴潮灾害及对策

较详细地分析了天津、河北沿海地区风暴潮时空分布规律、灾情、产生的原因, 指出近年来本区风暴潮发生频率和强度有明显增加的趋势, 而且造成的经济损失增长更快。在过去４０ ａ中, 每过１０ ａ 灾损约增加１０ 倍。并提出了防潮减灾对策     

Ecosystem health: I. Measuring ecosystem health

Ecosystem analysis has been advanced by an improved understanding of how ecosystems are structured and how they function. Ecology has advanced from an emphasis on natural history to consideration of energetics, the relationships and connections between species, hierarchies, and systems theory. Still, we consider ecosystems as entities with a distinctive character and individual characteristics. Ecosystem maintenance and preservation form the objective of impact analysis, hazard evaluation, and other management or regulation activities. In this article we explore an approach to ecosystem analysis which identifies and quantifies factors which define the condition or state of an ecosystem in terms of health criteria. We relate ecosystem health to human/nonhuman animal health and explore the difficulties of defining ecosystem health and suggest criteria which provide a functional definition of state and condition. We suggest that, as has been found in human/nonhuman animal health studies, disease states can be recognized before disease is of clinical magnitude. Example disease states for ecosystems are functionally defined and discussed, together with test systems for their early detection.This article is contribution VI in D.J. Schaeffer's Environmental Audit series.