Determination of 2-butoxyethanol emissions from selected consumer products and its application in assessment of inhalation exposure associated with cleaning tasks

Consumer products are important sources of human exposure to certain chemicals. Recent regulatory requirements for assessing human exposure to three glycol ethers, namely 2-methoxyethanol (ME), 2-ethoxyethanol (EE) and 2-butoxyethanol (BE), have prompted the investigation of these chemicals in consumer products and their emission characteristics. Thirteen products were selected for investigation based on their potential of containing the chemicals. Headspace results indicated that ME and EE were not present in any of the 13 selected products, while BE was detected in the headspace samples of seven products, of which five were household cleaning agents. Other related compounds such as 2-hexyloxyethanol (HE) and 2-(2-butoxyethoxy)ethanol (BEE) were also detected in the headspace samples of some products. BE emissions from five cleaning related products were measured using a field and laboratory emission cell (FLEC) with its subunit to provide emission data for inhalation exposure assessment purposes. These products had initial emission factors ranging from 145 to 938 mg m(-2) h(-1) under the experimental conditions. It was found that the emission factor of BE was inversely proportional to the dilution factor of the products. A good relationship was established between the emission factor of BE and its concentrations in water-based products. Based on product use scenarios developed by US EPA and an assumed "standard room," average daily inhalation exposure levels of a resident as a result of performing cleaning tasks were estimated to be 0.075 and 0.186 mg (kg b.w.)(-1) day(-1) for two all-purpose spray cleaners, and 0.004 and 0.006 mg (kg b.w.)(-1) day(-1) for two-spray glass cleaners, respectively.     

基于双层规划模型的城市固体废物管理系统优化研究

采用变权重组合模型和情景分析法,对北京市的城市固体废物(MSW)产量进行有效地预测.预测结果表明,北京市垃圾产量增幅不大但处理设施容量存在缺口.在科学预测的基础上,构建以温室气体(GHG)控制为上层目标,系统成本最小化为下层目标的双层规划模型(BLP-MG&MC).该模型的结果表明,焚烧和堆肥将是北京市MSW的主要处理方式;在3个规划时段内,GHG总排放量达到1.67×106 t(以CO2当量计),填埋场的CH4和焚烧厂的N2O是GHG排放的主要贡献者;系统总成本达到7.0×109元,其中,65%的成本来自于焚烧厂和堆肥厂.4种模型结果的对比分析表明,双层规划能提供综合经济和环境因素的管理方案.     

基于投入产出非线性模型的能源强度情景优化

节约资源在我国的\"十一五\"规划中已经上升到了基本国策的战略地位,降低能源强度是资源节约的一项具体体现。论文以行业最终需求为决策变量,以2010年能源强度最小为目标,构建了一个基于投入产出的能源强度非线性优化模型。在此基础上,设计了三方案九情景和一个强化节能情景,并采用遗传算法对模型进行求解。研究结论表明:如果不采取强化节能情景,能源强度的最优值区间为0.999 6~1.136 4 tce/104元,没有实现2010年能源强度降低20%的目标。如果实行强化节能,2010年能源强度可下降到0.943 9 tce/104元,相比2005年下降了21.75%,实现了\"十一五\"规划节能降耗20%的目标。     

消费品风险评价的伤害情景与三维矩阵集成方法

通过对比分析美国、欧盟及中国的消费品质量安全风险监管和评估现状,得出我国在消费品法律及标准、伤害监测与事故信息平台及公开、消费品风险辨识及评价程序等方面有待深化研究;基于2012年欧美等国家、地区对我国出口消费品的通报数据的统计分析,识别了主要消费品的隐患及危害类型,给出了伤害情景与三维矩阵集成的消费品风险评价方法,为消费品安全评价提供了新方法、新途径,并以婴儿车为例,进行了应用分析,检验了该方法的可行性。     

Irrigation Reliability Under Climate Change Scenarios: A Modeling Investigation in a River‐Based Irrigation Scheme in New Zealand1

Srinivasan, M.S., J. Schmidt, S. Poyck, and E. Hreinsson, 2011. Irrigation Reliability Under Climate Change Scenarios: A Modeling Investigation in a River‐Based Irrigation Scheme in New Zealand. Journal of the American Water Resources Association (JAWRA) 47(6):1261–1274. DOI: 10.1111/j.1752‐1688.2011.00568.x Abstract: The impact of climate change (CC) on irrigation reliability in a river‐based irrigation scheme in New Zealand was investigated. Reliability was defined as the river’s ability to meet the demand. Two future periods were considered, 2030‐49 (“2040”) and 2080‐99 (“2090”), and reliability at these periods were compared against those in 1980‐99 (“current”). A hydrology model, calibrated and validated for current condition, was applied to simulate flows for CC scenarios. Annual precipitation and mean temperatures were predicted to increase under CC scenarios over current condition. Occurrence of high intensity rainfall events indicated large flows under CC scenarios, though these increases could be occurring outside the irrigation season (September‐April). Compared to current condition, under CC scenarios, the number of days per season supply falling below demand could increase by 5 (2040) to 17% (2090). Snow storage plays a major role in sustaining flows in early spring under current condition. However, with increasing temperatures under CC scenarios, the average annual snow water storage could decrease from 155 mm (current) to 97‐134 mm (2040) and 40‐90 mm (2090). Under CC scenarios, to sustain the current levels of land and water uses in this scheme, storage options need to be explored.     

我国地方政府环保融资缺口解决方案的若干设想

环保融资缺口是我国环境保护事业发展的瓶颈。本文从财政投资、排污收费、利用外资、市场融资四个方面提出了一个系统性的解决方案。希望为环保融资困境提供一个可资借鉴的模式。     

危险化学品事故后果计算过程探讨

基于事故后果的风险评估方法是国内外进行安全评价和土地使用安全规划的基础方法之一。本文基于危险化学品种类和危险装置类型,对可能发生的事故情景和相应事故后果计算模型的选择方法进行了阐述,针对易燃、易爆、有毒危险化学品的事故后果计算过程进行了系统分析。最后对本文提出的事故后果分析方法进行了实例应用。本文的研究成果可为安全评价或土地使用安全规划等工作的开展提供必要的参考。     

考虑不确定性的多情景应急车辆综合调度模型

为提升不同应急情景下各救援力量的联合应急救援效率,降低救援风险,减少财产损失,采用情景分析的方法对应急状态不确定性进行参数估计,引入风险厌恶水平,构建一种以总调度成本和风险最小化为目标的应急车辆综合调度模型;运用非支配排序遗传算法(NSGA-II)求解目标函数值,通过仿真案例对比分析考虑情景与不考虑情景2种情况下的求解结果;利用模型分析不同情景下惩罚成本与风险厌恶水平的关系,给出合理风险厌恶水平值,选定最终调度方案。结果表明:该模型与方案能够有效满足不同应急情景下需求点的需求,提高救援效率,解决在情景与风险共同作用下的应急车辆综合调度问题。