废弃中药渣催化热解制取生物油的研究

利用热重分析仪(TGA)对植物类中药渣的热解特性进行了研究,用Coats-Redfern积分法计算了其热解动力学参数,得出中药渣热解反应符合一级反应动力学方程,其活化能较低,为36.0kJ/mol。考察了热解温度对气体、液体、固体产物的影响,在723K时,液体产物生物油产率最高,为39%。以介孔分子筛SBA-15以及分别负载Al、Sn、Ni、Cu和Mg的SBA-15作为催化剂,研究催化热解对气体、液体、固体产率及生物油组分的影响。研究表明,Al-SBA-15的催化效果较好,液体产率最高,为36%;采用元素分析仪和热值测定仪,得到用Al-SBA-15作为催化剂时生物油的氧质量分数最低,低位热值最高。用GC/MS对生物油组分的分析结果表明,添加Al-SBA-15后,热解产物中脂肪族和芳香族化合物增加,而含氧化合物减少。     

Land use in Korean tidal wetlands: impacts and management strategies

The coastal landscapes in southwestern Korea include a diverse array of tidal wetlands and salt marshes. These coastal zones link the ecological functions of marine tidal wetlands and freshwater ecosystems with terrestrial ecosystems. They are rich in biological diversity and play important roles in sustaining ecological health and processing environmental pollutants. Korean tidal wetlands are particularly important as nurseries for economically important fishes and habitats for migratory birds. Diking, draining, tourism, and conversion to agricultural and urban uses have adversely affected Korean tidal wetlands. Recent large development projects have contributed to further losses. Environmental impact assessments conducted for projects affecting tidal wetlands and their surrounding landscapes should be customized for application to these special settings. Adequate environmental impact assessments will include classification of hydrogeomorphic units and consideration of their responses to biological and environmental stressors. As is true worldwide, Korean laws and regulations are changing to be more favorable to the conservation and protection of tidal wetlands. More public education needs to be done at the local level to build support for tidal wetland conservation. Some key public education points include the role of tidal wetlands in maintaining healthy fish populations and reducing impacts of nonpoint source pollution. There is also a need to develop procedures for integrating economic and environmental objectives within the overall context of sustainable management and land uses.     

基于冷阴极触发管振动试验夹具的设计

介绍了一种基于冷阴极触发管性能检测及振动试验所需的夹具,从夹具材料的选取、结构设计和刚度要求进行了设计,分析了该夹具在制造过程中存在的关键问题及解决方法,并在振动试验中加以验证。     

低碳理念在工业园区规划环评中的应用低碳理念在工业园区规划环评中的应用

工业园区是温室气体排放的重要源头之一,工业园区规划环评应在规划的基础上,探讨如何在评价过程中通过制定合理的对策措施,促进园区低碳发展。本文分析了低碳发展理念纳入工业园区规划环评的工作重点,建议规划环评完善评价内容,在原有评价体系中融入园区温室气体排放特征、设定低碳发展评价指标、优化设计能源结构、构建低碳产业体系、低碳发展替代方案以及碳排放跟踪评价等内容,以达到规划环评指导工业园区按低碳路径发展的目的。     

中性红在柚子皮上的吸附机制研究

采用柚子皮作为生物吸附材料吸附去除中性红。研究了中性红的初始浓度、吸附时间及反应温度对吸附效果的影响。结果表明,当中性红溶液从100 mg/L升高到250 mg/L时,反应95 min后,柚子皮对中性红的吸附量从16.80 mg/g增加到40.00mg/g。中性红在柚子皮上的吸附在60 min内基本上可以达到平衡,且柚子皮对中性红的吸附过程为放热过程;二级吸附动力学方程能更好地描述中性红在柚子皮上的吸附行为;中性红在柚子皮孔隙中的扩散不是唯一的吸附速率控制步骤,这个吸附过程可能受多个步骤共同控制;柚子皮对中性红的吸附是自发吸附,Langmuir、Freundlich和Temkin吸附等温式能很好地拟合柚子皮对中性红的吸附过程,拟合相关系数分别达到了0.991 8、0.993 4、0.989 0。     

Air ion concentrations in various urban outdoor environments

Atmospheric ions are produced by many natural and anthropogenic sources and their concentrations vary widely between different environments. There is very little information on their concentrations in different types of urban environments, how they compare across these environments and their dominant sources. In this study, we measured airborne concentrations of small ions, particles and net particle charge at 32 different outdoor sites in and around a major city in Australia and identified the main ion sources. Sites were classified into seven groups as follows: park, woodland, city centre, residential, freeway, power lines and power substation. Generally, parks were situated away from ion sources and represented the urban background value of about 270 ions cm^?3. Median concentrations at all other groups were significantly higher than in the parks. We show that motor vehicles and power transmission systems are two major ion sources in urban areas. Power lines and substations constituted strong unipolar sources, while motor vehicle exhaust constituted strong bipolar sources. The small ion concentration in urban residential areas was about 960 cm^?3. At sites where ion sources were co-located with particle sources, ion concentrations were inhibited due to the ion-particle attachment process. These results improved our understanding on air ion distribution and its interaction with particles in the urban outdoor environment.     

Dynamic Tracking and Comprehensive Evaluation on the Natural Resources Security Elements and System in China

System theory,pressure-state-response and drivingpressure-state-impact-response model have been applied to establishing China's dynamic tracking evaluation system of natural resources security in this article.Based on analytic hierarchy process and Delphi methods,the natural resources security situation has been evaluated systematically from 1991 to 2007.The result showed that the overall level of China's natural resources security presented a downtrend from 1991 to 2007.The basic reasons are the pressure indicators such as population,GDP,natural resources trade increased gradually,resulting in tension and fragility of natural resources security.     

Factor analysis of corporate environmental responsibility

Under the current situation of environmental pollution and resources shortage, the research of corporate environmental responsibility (CER) is of great importance to promote the sustainable development of society. The article adopts the perspective of the Stakeholder Theory and environmental management to make the empirical analysis of CER. Consequently designed questionnaire investigation is carried out among 30 Shanghai enterprises during 2007 and 2008. Through the correlation analysis, principal component analysis, factor ordering, and variables reappearance of key factors, seven key indexes are identified in the original 35 variables. This article aims to provide reference for enterprise environmental management and forwards the study of Corporate Social Responsibility.     

基于加权TOPSIS法的旅游资源区际竞争力比较研究

旅游资源是旅游活动的客体,是旅游业赖以生存和发展的物质基础和前提条件。现有旅游资源区际竞争力的比较研究中,主要采用指数法、位序得分法和专家打分排序,主观因素影响过大。TOPSIS法是一种多属性决策方法,基本原理是通过构造决策问题中的各指标最优解和最劣解,计算比较对象贴近最优解和远离最劣解的程度,给出比较对象的优劣排序,作为决策判据,此方法可减少人为因素的干扰,提高评价结果的可靠性和可信度。首先阐述加权TOPSIS法,其次依据旅游资源的属性,构建旅游资源区际竞争力比较指标体系,在此基础上以长江三角洲16个城市为例,进行旅游资源区际竞争力实证研究。结果表明,地区间旅游资源存在较大的差异,苏州、杭州的旅游资源竞争实力最强,泰州、南通实力最弱。     

Congener-specific accumulation and environmental risk assessment of polybrominated diphenyl ethers in diverse Korean sewage sludge types

Industrial, domestic wastewater, and livestock sludge samples were collected from 23 wastewater treatment plants in Korea and analyzed for polybrominated diphenyl ethers (PBDEs). The concentrations of Σ₁₉PBDE ranged from 4.01 to 10,400 ng/g dry weight. The average Σ₁₉PBDE concentrations in industrial, domestic wastewater, and livestock sludge were 1,560?±?3,610, 402?±?148, and 27.6?±?50.4 ng/g dry weight, respectively. The composition of PBDEs differed according to the type of sludge. Among the PBDE congeners, BDE 209 was dominant in all sludge samples. After BDE 209, relatively high levels were found for BDE 28 and 47 from industrial sludge, BDE 47 and 99 from domestic wastewater sludge, and BDE 206, 207, and 208 from livestock sludge. Using hierarchical cluster analysis, sludges were divided into three groups according to PBDE congener composition. A risk assessment of PBDEs in sludge used for soil amendment was carried out. Preliminary results indicated that the potential risk of soil exposed to PBDEs in sludge was relatively low.