热电厂双膜法中水深度处理回用系统膜污染机制分析

以某热电厂实际规模的双膜法中水回用系统为考察对象,对膜污染结构、形貌、组成与特征进行了研究。结果表明：污染物以有机-无机-微生物复合形式存在,形成致密的膜污染层,无机物主要以P、S、Ca、Si、Mg为主,存在垂直分布特征;有机污染物以腐殖质类、蛋白质、微生物代谢产物为主,且研究发现RO过程富里酸类物质主要为微生物源。碱性清洗液具有更佳的膜污染清洗效果。通过分析可知：微生物污染是膜污染暴发的关键原因,其以杆菌和球菌为主,且具有显著的垂直分布特征;表层微生物主要是α和β变形菌,底层中γ变形菌丰度显著增加。微生物污染垂直分布的主要原因是杀菌和化学清洗过程的选择作用,γ变形菌是先锋微生物,是形成稳定膜污染层的关键物种。因此,控制微生物的滋生是RO中水深度处理的关键,这个过程主要包括预处理工艺的选择和优化杀菌、阻垢和化学清洗策略等。     

三峡水库入库溪流中麦氏花翅蜉(蜉蝣目:四节蜉科)的生活史研究

开展水生昆虫生长过程研究对掌握研究区域水生生物的生物学特征和研究区域生态环境状况等均具有重要作用,可为构建和完善研究区域河流生态环境保护体系提供科学参考。于2017年逐月对香溪河库湾入库支流(螃蟹溪)中的一种水生昆虫——麦氏花翅蜉(Baetiella macani)的种群进行了研究,基于大小频率法、幼虫期有效积温条件进行了生活史性状分析和验证。结果显示:麦氏花翅蜉为三化性昆虫,包含一个冬季世代和两个夏季世代。冬季世代幼虫的发育历期为3~4个月,所需有效积温为1 286 ℃;夏季世代幼虫的发育历期为1~2个月,所需有效积温为757 ℃。研究结果丰富了中国地区水生昆虫的生活史性状信息,并首次呈现了花翅蜉属的生活史特征。     

Influence of driving cycles on exhaust emissions and fuel consumption of gasoline passenger car in Bangkok

The influence of different driving cycles on their exhaust emissions and fuel consumption rate of gasoline passenger car was investigated in Bangkok based on the actual measurements obtained from a test vehicle driving on a standard chassis dynamometer. A newly established Bangkok driving cycle (BDC) and the European driving cycle (EDC) which is presently adopted as the legislative cycle for testing automobiles registered in Thailand were used. The newly developed BDC is constructed using the driving characteristic data obtained from the real on-road driving tests along selected traffic routes. A method for selecting appropriate road routes for real driving tests is also introduced. Variations of keyed driving parameters of BDC with different driving cycles were discussed. The results showed that the HC and CO emission factors of BDC are almost two and four times greater than those of EDC, respectively. Although the difference in the NOx emission factor is small, the value from BDC is still greater than that of EDC by 10%. Under BDC, the test vehicle consumes fuel about 25% more than it does under EDC. All these differences are mainly attributed to the greater proportion of idle periods and higher fluctuations of vehicle speed in the BDC cycle. This result indicated that the exhausted emissions and fuel consumption of vehicles obtained from tests under the legislative modal-type driving cycle (EDC) are significantly different from those actually produced under real traffic conditions especially during peak periods.     

河湖水系连通的理论探讨

在全球气候变化和水资源形势日趋严峻的背景下,为了从根本上提高水资源统筹配置能力、改善河湖健康状况和增强抵御水旱灾害能力,河湖水系连通作为国家新时期的一个治水方略被提出。当前关于河湖水系连通的理论基础研究要落后于实践,尚在探索之中。论文尝试从河、湖与水系等水循环基本概念入手,探讨水系的结构、特征和连通性,揭示水系连通的水循环物理机制,并进一步分析河湖水系连通的战略思想,探明其中涉及的几个关键水循环基础问题,包括水量平衡、能量平衡、水资源可再生性、水循环尺度等问题,为河湖水系连通战略的实施和理论体系的建立奠定基础。     

兰州大石鸡不同生活史阶段栖息地选择的初步研究

大石鸡不同生活史阶段选择不同的栖息地．集群期选择坡度小、低海拔、东向的山坡和坟地．配对期选择坡度３０～６０°、海拔居中的栖息地,选择的栖息地范围较宽．产卵期多见于坡度小、地面环境异质性小、海拔高的农田和山坡．育雏期选择植物丛密度低、坡度小、海拔高的山坡和农田．繁殖后期选择植物丛密度低、低海拔、东向的山坡和沟底．不同生活史阶段植被覆盖度、植物高度、环境类型和坡向差异不显著,坡度差异显著,植物丛密度、海拔高度和地面环境异质性差异极显著．在各环境因子中,只有地面环境异质性对大石鸡栖息地选择的影响较显著．地形、食物和气候可能是影响大石鸡栖息地选择的根本因素．     

农业生态系统的氮素循环研究进展

在自然和人为作用的双重驱动下,地球表面氮素的生物地球化学过程及其环境效应成为当前全球变化中区域研究的重要内容。探讨了氮素循环各个过程及其数量特征,对氮素循环模型进行了介绍,并对当前生态系统中氮素循环的研究热点进行了简要的论述。     

Research on whole life cycle carbon emission model of typical buildings

Based on the theory of life cycle assessment (LCA), this article analyzes the influence factors on carbon emissions from residential buildings. In the article, the life cycle of residential buildings has been divided into five stages: building materials production period, construction period, operation and maintenance period, demolition period, and solid waste recycle and disposal period. Based on this definition, the authors provide a theoretical model to calculate carbon emissions of residential building life cycle. In particular, the factor of human activities was introduced in the calculation of carbon emissions from the buildings. Furthermore, the authors put forward a model for calculation with the unit of carbon emissions for per-capita living space.     

畜牧业“碳排放”到“碳足迹”核算方法的研究进展

全球变暖趋势日益加剧,不仅影响农业可持续发展,而且威胁到人类生存。畜牧业碳排放因其在农业碳排放中乃至全球碳排放中占比较大而日益备受关注。准确核算畜牧业碳排放是制定切实可行的碳减排政策的前提,也为我国在气候变化下承担共同但有差别的减排责任提供话语权。本文基于研究范式的演进,对畜牧业碳排放到碳足迹核算方法的研究发展进行了系统梳理,研究表明,在学者的不断研究与质疑下,畜牧业碳排放到碳足迹的核算方法经历了从OECD核算法、IPCC系数法到生命周期法与投入-产出法的演变与完善,学术界认为区域异质性、养殖规模与管理方式均影响碳足迹;散养比规模化养殖产生更多的碳排放,舍饲比户外放牧排放更多的碳。畜牧业碳足迹核算能够更加全面地反映畜牧业全生命周期的碳排放情况,但由于研究假设、研究方法及研究样本等差异导致不同区域、不同畜产品的碳排放核算结果存在不确定性。运用生命周期法和投入-产出法对欧盟成员国畜牧业碳排放的核算结果基本一致,但运用IPCC系数法和全生命周期法对中国畜牧业碳排放核算中,牛、猪和羊的碳排放量排序结果不尽一致。鉴于核算结果的差异性,本研究对不同核算方法的起源、最早采用时间、特点、局限性等方面进行了归纳总结,并建议后续研究探讨基于生命周期评价的畜牧业碳足迹研究边界的延伸性,标准化畜牧业碳排放或碳足迹核算,避免学者重复核算畜牧业碳排放,以便深入展开畜牧业碳排放其他方面的研究。     

Proposing of new building scheme and composite towards global warming mitigation for Malaysia

The building sector has been regarded as a potential sector where there is large capacity to reduce the climate change effect. This study has proposed solutions to mitigate environmental impacts and achieve low CO₂ emission from residential sector. Therefore, full life cycle assessment (LCA) has been run to assess the CO₂ emission and its effect on the atmosphere and climate change. Based on the result, timber scheme is the best choice due to releasing less CO₂ emissions to the atmosphere. However, house builders in Malaysia have almost completely neglected timber as a building material, with timber use as building components reduced to 5%. In this study, LCA Software was used to assess CO₂ emissions from different wall construction. The alternative building scheme has been made by reinforce steel stud, wooden beam and timber wall (S8) to improve the scheme deficiency while releasing less CO₂ emissions compared to other schemes. Therefore, S8 has a decreased CO₂ effect by 85% less than precast concrete frame and 90% less than brick over their lifetime. (S8) increased the load bearing compared to conventional timber beam. Thus, new scheme S8 could be replaced by current scheme and promote more adjustable scheme for Malaysian housing.     

矿山清洁生产示范研究

矿山清洁生产具有双重性。矿山生命周期决定了矿山清洁生产体系的特殊性。矿山清洁生产体系是由培训体系、生命周期清洁生产体系和监合与审核体系构成的一个系统，生命周期清洁生产体系包括从资源勘探-规划设计-开发-闭矿-后续土地利用与监测的各个阶段。与其他行业相比，矿山清洁生产难度大且明显滞后，开展矿山清洁生产示范研究势在必行。