钢包旋转塔的倾覆安全分析

介绍了钢包旋转塔的工作性质、结构特点和潜在危险 ,其抵抗倾覆的主要联接件地脚螺栓的结构、安装方法和预紧力的计算 ,在工作载荷、安装载荷下的强度分析 ,并探讨在生产运行期间的检查、维护等有关安全问题     

Estimation of Organic Carbon Blank Values and Error Structures of the Speciation Trends Network Data for Source Apportionment

Abstract

Because the particulate organic carbon (OC) concentrations reported in U.S. Environment Protection Agency Speciation Trends Network (STN) data were not blank corrected, the OC blank concentrations were estimated using the intercept in particulate matter ≤2.5 µm in aerodynamic diameter (PM_2.5) regression against OC concentrations. The estimated OC blank concentrations ranged from 1 to 2.4 μg/m³ showing higher values in urban areas for the 13 monitoring sites in the northeastern United States. In the STN data, several different samplers and analyzers are used, and various instruments show different method detection limit (MDL) values, as well as errors. A comprehensive set of error structures that would be used for numerous source apportionment studies of STN data was estimated by comparing a limited set of measured concentrations and their associated uncertainties. To examine the estimated error structures and investigate the appropriate MDL values, PM_2.5 samples collected at a STN site in Burlington, VT, were analyzed through the application of the positive matrix factorization. A total of 323 samples that were collected between December 2000 and December 2003 and 49 species based on several variable selection criteria were used, and eight sources were successfully identi?ed in this study with the estimated error structures and min values among different MDL values from the ?ve instruments: secondary sulfate aerosol (41%), secondary nitrate aerosol (20%), airborne soil (15%), gasoline vehicle emissions (7%), diesel emissions (7%), aged sea salt (4%), copper smelting (3%), and ferrous smelting (2%). Time series plots of contributions from airborne soil indicate that the highly elevated impacts from this source were likely caused primarily by dust storms.     

An Experimental and Metamodeling Approach to Tensile Properties of Natural Fibers Composites

Journal of Polymers and the Environment - The present work presents an analysis of the tensile properties of Palm as well as Luffa natural fiber composites (NFC) in high density polyethylene...     

Investigation of migration rule of rainwater for sponge city roads under different rainfall intensities

Environmental Geochemistry and Health - Urban development and climate change have led to severe waterlogging in cities. To study the degree of mitigation of urban waterlogging using the design of...     

Association of urinary or blood heavy metals and mortality from all causes,cardiovascular disease,and cancer in the general population: a systematic review and meta-analysis of cohort studies

Environmental Science and Pollution Research - Amounting epidemiological evidence has shown detrimental effects of heavy metals on a wide range of diseases. However, the effect of heavy metal...     

Polycyclic aromatic hydrocarbons,long non-coding RNA expression,and DNA damage in coke oven workers

Environmental Science and Pollution Research - Exposure to polycyclic aromatic hydrocarbons (PAHs) was associated with DNA damage, while the roles of long non-coding RNAs (lncRNAs) in the...     

Migration,Transformation and Removal of Macrolide Antibiotics in The Environment: A Review

Environmental Science and Pollution Research - Macrolide antibiotics (MAs), as a typical emerging pollutant, are widely detected in environmental media. When entering the environment, MAs can...     

集约化畜禽养殖对环境的污染及防治研究

治理集约化畜禽养殖废弃物污染,开展废弃物的资源化利用,是解决中国畜牧业环境污染问题的主要路径。文章详述了中国畜禽养殖业污染问题的产生及对环境可能造成的影响,分析了畜禽废弃物处理措施与资源化利用的主要方式及其效果和存在的问题,并提出了控制畜禽粪污染物的对策和环境管理建议,将有助于推动中国畜禽养殖业的可持续发展,改善农业生态环境及农村人居环境。     

Industrial sustainability in China: practice and prospects for eco-industrial development

China is a large densely populated country undergoing rapid industrialization and is becoming one of the world's biggest consumers of natural resources. This circumstance provides a sharp contrast with other countries. As China is so significant in the global economy, studies of its eco-industrial development are very important. In this study we examined the state of eco-industrial development in China and have drawn conclusions from this analysis about some of the future prospects for sustainable development. In the analysis, we investigated the application of industrial ecology concepts by reference to several case studies. We have therefore described the current environmental situation in China, and have provided an overview of eco-industrial development and its implementation. Constraints to industrial sustainability in China have also been examined. We consider that eco-industrial development in China is in its infancy, and that closed loops involving chains and industrial symbiotic webs are the technological key and core of successful initiatives in the application of industrial ecology. In the case studies, we found that each system has different characteristics and management concerns. Our major conclusion is that even though China's Agenda 21 highlights the principles and sets the directions for eco-industrial development, these have not yet become essential ingredients in the country's industrial policy and practice for implementing Agenda 21.