Are current Chinese national ambient air quality standards on 24-hour averages for particulate matter sufficient to protect public health?

With rapid economic development and urbanization in recent decades, China has experienced the worsening of ambient air quality. For better air quality management to protect human health, Chinese government revised national ambient air quality standards(NAAQS) for particulate matter(PM) in 2012(GB3095-2012). To assess the effectiveness of current NAAQS for PM on public health in Chinese population, we conducted a metaanalysis on published studies examining the mortality risk of short-term exposure to PM with aerodynamic diameters less than 10 and 2.5 μm(PM_(10) and PM_(2.5)) in China. The reported24-hour concentrations of PM_(10) and PM_(2.5) in studies ranged from 43.5 to 150.1 μg/m~3 and 37.5 to 176.7 μg/m~3. In the pooled excess, mortality risk estimates of short-term exposure to PM.In specific, per 10 μg/m~3 increase in PM_(10), we observed increases of 0.40%(95%CI: 0.33%,0.47%), 0.57%(95%CI: 0.44%, 0.70%) and 0.49%(95%CI: 0.40%, 0.58%) in total, respiratory and cardiovascular mortality, per 10 μg/m~3 increase in PM_(2.5), we observed increases of 0.51%(95%CI: 0.38%, 0.63%), 0.62%(95%CI: 0.52%, 0.73%) and 0.75%(95%CI: 0.54%, 0.95%) in total,respiratory and cardiovascular mortality. Finally, we derived 125 μg/m~3 for PM_(10) and 62.5 μg/m~3 for PM_(2.5) as 24-hour recommendation values based on the pooled estimates. Our results indicated that current Chinese NAAQS for PM could be sufficient in mitigating the excess mortality risk from short-term exposure to ambient PM. However, future research on longterm exposure cohort studies in Chinese population is also essential in revising annual averages for PM in Chinese NAAQS.     

重金属离子快速检测技术研究与应用进展

在突发环境污染事件和区域生态风险筛查中迫切需要环境样品中重金属离子的快速检测技术手段。环境样品中重金属离子的快速检测技术有电化学方法和生物学方法。电化学检测方法主要是阳极溶出伏安法(AnodicStripping Voltammetry,ASV),可以同时检测多种重金属离子,有标准化认证的产品,但是检测成本相对较高。随着纳米粒子技术(Nanoparticles,NPs)和石英微天平分析技术(Quartz Crystal Microbalance,QCM)的引入,ASV法的检测成本将不断降低;生物检测方法包括免疫检测(Immunoassay,IA)和功能DNA(Functional DNA)检测技术。重金属离子的免疫检测技术样品通量大,检测成本低,已经广泛用于食品行业,其中汞离子的免疫检测方法已经成为环境样品标准检测方法之一。免疫检测传感器技术将拓展重金属离子的快速检测的应用空间。功能DNA传感器检测的研究为重金属离子的快速检测提供了新的技术手段,但是这些仅限于实验室研究,还没有达到实际应用的水平。     

云南崇圣寺地基变形对南北小塔倾斜的影响

本文依托云南崇圣寺三塔保护工程项目,以崇圣寺三塔中发生明显倾斜的南、北小塔为主要研究对象,在查明场地工程地质条件的基础上,利用地基沉降量计算公式计算了南、北小塔地基的沉降量和不均匀沉降差值,结果表明北小塔的地基不均匀沉降引起的塔体倾斜仅占塔体总倾斜量的25.2％,南小塔地基不均匀沉降引起的塔体倾斜占塔体总倾斜量的20....     

炼化企业防恐脆弱性评估指标体系构建及评估方法探讨

脆弱性评估是企业防恐风险评估的关键环节。结合炼化企业装置设施特征,建立了以易损性、敏感性、承灾能力以及应急能力等4项一级指标、17项二级指标的防恐脆弱性评估指标体系,采用模糊层次分析法进行了防恐脆弱性半定量化评估,并根据评估结果提出了某炼化企业关键资产的安保策略改进方向。     

基于环境温度传感的节水调节器设计研究

传统节水调节器使用半自动机械控制,能够实现部分水资源节约,但在新疆等温度交替变化明显地区,无法根据温度变化情况实现自动控制节水调节,从而造成部分水资源浪费。为此提出基于环境温度传感的节水调节器设计。采用concise结构设计,在阻挠蝶板上增加环境温度传感装置,依托沿程阻力系数判定温度传感器节水调节系数ξ,通过不同ξ值的反馈,针对性的采取相应调节措施;使用调节Accurate检验机制,对温度变化幅度k进行测定,确定调节幅度有效取值,完成节水调节器的自动调节控制,实现基于环境温度传感的节水调节器设计。     

Energy-saving benefits from plug-in hybrid electric vehicles: perspectives based on real-world measurements

Promoting plug-in hybrid vehicles (PHEV) is one important option to mitigate greenhouse gas emissions and air pollutants for road transportation sector. In 2015, more than 220,000 new PHEVs were registered across the world, indicating a 25-fold growth during 2011–2015. However, more criticizes have been put forward against the current energy efficiency regulations for vehicles that are mostly depended on laboratory measurements. To better understand the real-world energy-saving and emission mitigation benefits from PHEVs, we conducted on-road testing experiments under various operating conditions for two in-use PHEVs in Beijing, China. Our results indicate that air condition usage, congested traffic conditions, and higher loading mass could significantly increase energy consumption and shorten actual all-electric distance for PHEVs. For example, the worst case (14.1 km) would occur under harshest usage conditions, which is lower by at least 35% than the claimed range over 20 km. In charge sustaining (CS) mode, real-world fuel consumption also presents a large range from 3.5 L/100 km to 6.3 L/100 km because of varying usage conditions. Furthermore, various vehicle users have significantly different travel profiles, which would lead to large heterogeneity of emission mitigation benefits among individual PHEV adopters. Therefore, this study suggests that the global policy makers should use real-world energy efficiency of emerging electrified powertrain techniques as criteria to formulate relevant regulations and supportive policies.     

我国当前城乡建设用地置换的实践探索及问题剖析

当前我国城乡建设用地利用存在着城市建设用地指标紧缺、农村建设用地低效利用和城乡建设用地"双增"大量侵占耕地等问题。城乡建设用地增减挂钩政策推动下的城乡建设用地置换有望成为破解该问题的综合途径。2004年开始,伴随相关政策陆续出台,城乡建设用地置换实践在多个省市试点推进,其中江苏省万顷良田建设工程、天津市宅基地换房、山东省农村社区化、重庆市地票交易市场的实践较为典型。基于上述典型案例和系统要素分析,总结了实践的问题、根源与演进,认为目前系统中的要素与相应的操作环节中存在问题隐患且部分问题表现突出;实践中主要以涉及"非自愿"置换、补偿与保障不足、生产生活方式改变等的农民利益受损问题较为突出;问题的根源集中在三个方面,即国家层面的约束性的法律、法规、政策尚不健全,地方政府操作不合理和缺乏科学研究支撑。今后的实践中,应该建立统一的城乡土地市场并逐步完善政府主导下的城乡土地市场运行机制,建立科学合理的征地补偿机制,深入开展相关科学研究,遵循集约型用地增长模式,同小城镇建设紧密结合,注重保护村落景观风貌。     

海河流域草地生态系统服务功能及其价值评估

草地生态系统为人类提供了畜产品和生命支持两个方面的多种服务功能,但人们常关注产品提供功能而忽视生命支持功能。研究采用联合国千年生态系统评估框架,构建了海河流域草地生态系统服务功能的评估指标体系,并以2005年为基准年,运用市场价值法、影子价格法等多种方法对海河流域草地生态系统进行经济价值评估。结果表明,海河流域草地面积为6.67×10¹⁰ m²,提供产品、固碳、保持土壤、净化环境等8项服务功能的总价值为2 216.28×10⁸元,单位面积价值为3.32元/(m²·a)。其中,提供产品的价值量最大,占总价值的31.3%,其次是固碳和营养物质保持功能的价值,分别占总价值的26.8%、22.2%。海河流域草地生态系统除了具有重要的产品提供功能外,固碳、营养物质保持等生命支持功能的巨大经济价值也不容忽视,平衡兼顾草地生态系统的产品提供功能和生命支持功能有助于促进海河流域经济社会发展与生态保护的协调。