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571.
随着低碳经济的发展,人们意识到环境问题日益严重,尤其作为企业,如何更好地履行社会责任需重点关注。低碳经济不仅影响企业的经济活动,而且使企业的会计核算面临更大的挑战。与传统的会计相比,环境资源会计在加强环境资源管理、促进低碳经济发展方面起到至关重要的作用。然而中国目前还没有构建完善的环境资源会计理论体系来指导相关工作。基于低碳经济视角的环境资源会计核算分析了环境资源会计的内涵、核算对象、目标、确认、计量和信息披露,形成了核算框架,为环境资源会计的具体实施提供参考。  相似文献   
572.
Carbon dioxide (CO2) adsorption on a standard metal-organic framework Mg2(dobdc) (Mg/DOBDC or Mg-MOF-74) and a tetraethylenepentamine (TEPA) modified Mgz(dobdc) (TEPA-Mg/DOBDC) were investigated and compared. The structural information, surface chemistry and thermal behavior of the adsorbent samples were characterized by X-ray powder diffraction (XRD), infrared spectroscopy (IR), thermogravimetric analysis (TGA) and nitrogen adsorption-desorption isotherm analysis. CO2 adsorption capacity was measured by dynamic adsorption experiments with N2-CO2 mixed gases at 60℃. Results showed that the CO2 adsorption capacity of Mg/DOBDC was significantly improved after amine modification, with an increase from 2.67 to 6.06 mmol CO2/g adsorbent. Moreover, CO2 adsorption on the TEPA-Mg/DOBDC adsorbent was promoted by water vapor, and the adsorption capacity was enhanced to 8.31 mmol CO2/g absorbent. The adsorption capacity of the TEPA-Mg/DOBDC adsorbent dropped only 3% after 5 consecutive adsorption]desorption cycles. Therefore, this kind of adsorbent can be considered as a promising material for the capture of CO2 from flue gas.  相似文献   
573.
为探究大气环境中污染物与气象要素交互作用对PM2.5浓度变化的影响特征,利用成都市2014~2020年逐日大气污染物资料以及同期的气象资料,采用广义相加模型(GAMs)分析不同影响因素对当地PM2.5浓度变化的影响效应.结果表明,单影响因素GAMs模型中,无论全年还是冬季,PM2.5浓度与平均气温(T)、相对湿度(RH)、平均风速(Wind)、降水量(Prec)、O3、NO2、SO2和CO间均呈非线性关系,其中CO、NO2、SO2T和Wind对PM2.5浓度影响较大,与全年不同的是,冬季T和O3对PM2.5浓度变化的影响效应较全年明显减弱.多影响因素的GAMs模型中,T、Wind、RH、CO、NO2、SO2和O3这7个解释变量对PM2.5浓度变化的影响均较显著,构建的全年多影响因素GAMs模型调整后的R2=0.759,方差解释率为76.42%,冬季R2=0.708,方差解释率为72.2%,无论是全年还是冬季,CO都是PM2.5浓度变化的主导影响因素.GAMs交互效应模型发现,全年弱低温(7℃左右)+高相对湿度+高浓度CO+高浓度NO2+高浓度SO2协同作用条件下有利于PM2.5浓度的生成;冬季低Wind+高RH+高浓度CO+高浓度NO2+高浓度SO2共存条件下有利于PM2.5的生成,即该条件对PM2.5浓度的生成有协同放大效应.运用GAMs模型能够对PM2.5污染的主导影响因素进行识别,并定量化分析影响因素单效应及其交互作用对PM2.5浓度变化的影响特征,对PM2.5浓度污染防控研究具有重要指示意义.  相似文献   
574.
随着城市化的推进,城市的脆弱性不断加剧。近年来频发的生产安全事故,凸显了传统风险治理范式的局限性。源头防控、多元参与、数据驱动是当下生产安全风险治理的重要议题,而多元主体风险和系统性风险是治理的焦点。以整体性思维为指引,建构“三生”空间相互作用下的“双环模型”,为安全多维及时空多维视角下生产安全风险的治理提供理论基础和总体思路。挖掘信息技术对国土空间动态监测、风险认知积累和风险防控能力成长的积极作用,提出“扁平化”的风险监测评估框架体系并探讨信息平台的需求与架构。以风险交织的化工行业为例,重点关注工业园区主导下的生产安全风险多元防控范式和基础框架,为不同行业的多类型风险防控提供思路借鉴。  相似文献   
575.
Economy-wide material flow accounting and analysis (EW-MFA) is considered a convenient tool for monitoring the vast range of issues related to the consumption of materials. As an increase in recycling is considered a crucial way of decreasing environmental pressures from this consumption, it makes sense to develop an indicator based on EW-MFA which would incorporate recycling flows. A prominent example of such an indicator is the cyclical use rate, which was developed by the Japanese Fundamental Plan for Establishing a Sound Material-Cycle Society.We calculated this indicator for the Czech Republic for 2002–2011 and proved that it can also be calculated for countries other than Japan, even though we encountered some unclear methodological issues related to specific features of the Czech waste management system. We further developed two modifications of the indicator taking into consideration that one purpose of the cyclical use rate is to express the ratio of consumption of secondary (recycled) materials and primary raw materials. We discussed these modifications and showed that overall cyclical use rate in the Czech Republic lags behind Japan both in terms of absolute value and trend development, although the indicator is higher for biomass in the Czech Republic. We also showed that this unfavorable evaluation is in contradiction with some classic waste indicators, such as treatment of waste by main treatment methods which is favorably evaluated in the Czech Republic. We concluded that it would be advisable to analyze measures for increasing recycling rates introduced by Japan and assess their possible transposition into the Czech Republic's institutional and legal framework for waste management.  相似文献   
576.
• Framework of indicators was established based on energy efficiency and recovery. • Energy neutrality potential of 970 wastewater treatment plants was evaluated. • Analysis of characteristics and explanatory factors was carried out. • Pathways for improving the energy neutrality potential were proposed. Wastewater treatment plants (WWTPs) consume large amounts of energy and emit greenhouse gases to remove pollutants. This study proposes a framework for evaluating the energy neutrality potential (ENP) of WWTPs from an integrated perspective. Operational data of 970 WWTPs in the Yangtze River Economic Belt (YREB) were extracted from the China Urban Drainage Yearbook 2018. The potential chemical and thermal energies were estimated using combined heat and power (CHP) and water source heat pump, respectively. Two key performance indicators (KPIs) were then established: the energy self-sufficiency (ESS) indicator, which reflects the offset degree of energy recovery, and the comprehensive water–energy efficiency (CWEE) indicator, which characterizes the efficiency of water–energy conversion. For the qualitative results, 98 WWTPs became the benchmark (i.e., CWEE= 1.000), while 112 WWTPs were fully self-sufficient (i.e., ESS≥100%). Subsequently, four types of ENP were classified by setting the median values of the two KPIs as the critical value. The WWTPs with high ENP had high net thermal energy values and relatively loose discharge limits. The explanatory factor analysis of water quantity and quality verified the existence of scale economies. Sufficient carbon source and biodegradability condition were also significant factors. As the CWEE indicator was mostly sensitive to the input of CHP, future optimization shall focus on the moisture and organic content of sludge. This study proposes a novel framework for evaluating the ENP of WWTPs. The results can provide guidance for optimizing the energy efficiency and recovery of WWTPs.  相似文献   
577.
高职高专院校主要培养"实践型"人才,而非"学术型"人才,但在传统的实验教学中存在验证性实验多,而综合性、设计性实验少的现象,不利于培养学生积极探索、合作交流、创造性解决问题的能力。分组互动教学具有调动学生的学习积极性,增强合作与竞争意识,培养独立思考与团队精神,提高实践能力等优点。因此有必要在环境综合实验教学采用分组互动教学法,将不同层次的学生均衡地分布在各个小组中,使学生由被动接受变为主动参与,教师由过去的"主讲"变为"主导",充分调动学生的动脑、动口、动手能力。  相似文献   
578.
This paper builds on and extends previous research to contribute to ongoing discussion on the use of resource and carbon accounting tools in regional policy making. The Northern Visions project has produced the first evidence-based footpath setting out the actions that need to be taken to achieve the step changes in the Ecological and Carbon Footprint of Northern Ireland. A range of policies and strategies were evaluated using the Resources and Energy Analysis Programme. The analysis provided the first regional evidence base that current sustainable development policy commitments would not lead to the necessary reductions in either the Ecological Footprint or carbon dioxide emissions. Building on previous applications of Ecological Footprint analysis in regional policy making, the research has demonstrated that there is a valuable role for Ecological and Carbon Footprint Analysis in policy appraisal. The use of Ecological and Carbon Footprint Analysis in regional policy making has been evaluated and recommendations made on ongoing methodological development. The authors hope that the research can provide insights for the ongoing use Ecological and Carbon Footprint Analysis in regional policy making and help set out the priorities for research to support this important policy area.  相似文献   
579.
安全人机工效虚拟仿真实验系统设计   总被引:1,自引:0,他引:1  
虚拟仿真技术可有效解决安全生产领域基础理论和应用技术研究过程不能进行试验验证的技术难题.首先阐述了安全人机工效虚拟仿真实现系统的构成以及各部分功能,确定了以Jack软件的可视性分析、可达性分析、工作姿势分析、疲劳恢复分析、受力分析等人因分析功能为核心,建立集开发平台、展示平台、交互平台和数据分析平台为一体的安全人机工效虚拟仿真实验系统.分析了系统集成的关键技术,对比了不同类型动作捕捉器的基本原理和优缺点,结合安全人机工效实验需求,确定了采用电磁式动作捕捉器的系统集成方案,以及动作捕捉器、数据手套和虚拟仿真展示平台的集成方法,并对本实验系统的应用前景进行了展望.  相似文献   
580.
This paper presents a holistic strategy on the interaction of activities in the Elbe river basin and their effects on eutrophication in the coastal waters of the German Bight. This catchment–coastal zone interaction is the main target of the EUROCAT (EUROpean CATchments, catchment changes and their impact on the coast) research project, with the Elbe being one of eight case studies. The definition of socio-economic scenarios is linked with the application of models to evaluate measures in the catchment by estimation of nutrient emissions with MONERIS (MOdelling Nutrient Emissions in RIver Systems), and their effects on coastal waters with the ecosystem model ERSEM (European Regional Seas Ecosystem Model). The cost effectiveness of reduction measures will then be evaluated by application of the CENER model (Cost-Effective Nutrient Emission Reduction) and a multi-criteria analysis. Finally, the interpretation of ecological integrity is used as a measure to describe ecological impacts in an aggregated form.  相似文献   
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