Using the IPAT identity and decoupling analysis to estimate water footprint variations for five major food crops in China from 1978 to 2010

Evaluations of water footprint (WF) used to enhance performance of policies on water utilization will benefit from combining WF analysis with methods from sustainability analysis. For this purpose, this paper analyzes the WF of China’s five main food crops, which together account for roughly 33 % of the nation’s water consumption. We assess distributional equity at the provincial scale and use the IPAT identity and a decoupling analysis to assess the scale of both national and provincial WF consumption, the factors influencing the WF fluctuation, and the efficiency of water allocation. Results show that although it is difficult in the short term to end the unsustainable WFs of China’s five main food crops, more efficient allocation can be achieved through appropriate agricultural policy modification. In the long term, distributional equity at the provincial level must be the key factor in achieving sustainable agriculture in China.     

Pollution of hazardous substances in industrial construction and demolition wastes and their multi-path risk within an abandoned pesticide manufacturing plant

Exploration of heavy metals and organic pollutants, their leaching capacity along with health and environmental risks in contaminated industrial construction and demolition waste (ICDW) within a pesticide manufacturing plant were investigated. A maximum content of 90.8 mg?kg^–1 Cd was found present in the wastes, which might originate from phosphorus rocks and industrial sulfuric acid used in pesticide production processes. An average concentration of 979.8 mg?kg^–1 dichlorovos and other 11 organophosphorus pesticide were also detected. Relatively high leaching rates of around 4.14‰were obtained from laboratory simulated ICDW using both glacial acetic acid-sodium hydroxide and deionized water. Pesticide pollutants had the strongest tendency to retaining on dry bricks (leaching rate 1.68‰) compared to mortar-coatings, etc. due to their different physical characteristics and octanol-water partioning coefficient. Mobility of pesticide from on-site ICDW by water was spatially correlated to waste types, process sections and human activities, with a flux of leaching rate between 5.9‰ to 27.4%. Risk-based corrective action (RBCA) model was used to simulate the risk of contaminated ICDW debris randomly scattered. Oral and dermal ingestion amount by local workers was 9.8 × 10^–3 and 1.9 × 10^–2 mg?(kg?d)^–1, respectively. Potential leaching risk to aquatic systems exceeded the limit for nearly 75% waste. Environmental and health risk exceedance was found in most ICDW, while the risk value of the most severely contaminated brick waste was 660 times beyond critical level. Implications for waste management involving construction and deconstruction work, waste transferring and regulation supplying were also provided.

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可见光下氮掺杂罗丹明B分子印迹TiO_2的选择性光催化性能

采用溶胶-凝胶法和分子印迹技术,以尿素为氮源、罗丹明B为模板分子制备了氮掺杂罗丹明B分子印迹TiO_2粉末(N-TiO_2-RhB),并对样品进行了XRD、UV-Vis DRS和BET表征。表征结果显示:氮掺杂和分子印迹一定程度改善了样品的孔隙结构和孔径分布,N-TiO_2-RhB的比表面积和孔体积分别为TiO_2的1.9倍和1.5倍;氮掺杂使TiO_2的光吸收带边发生红移,而分子印迹不能改变催化剂的光吸收带边。N-TiO_2-RhB具有最佳的可见光活性和选择性,对罗丹明B的降解率高达92.7%。对罗丹明B、罗丹明6G、甲基紫和甲基绿的降解过程均符合一级反应动力学方程。     

水污染分析校准用汞溶液的研制

研制了水污染分析校准用汞溶液。采用原子荧光光谱法对样品进行了均匀性和稳定性检验,对样品的量值进行了验证并进行了不确定度评定。检验结果表明:汞溶液均匀性良好,室温条件下可稳定36个月以上;样品的标准值为100 mg/L,扩展不确定度为2 mg/L。样品量值与美国AccuStandard公司同种标准物质具有一致性。可用于水中汞检测的测定标准、质量控制、分析方法研究以及实验室能力验证等方面。     

碳材料促进废水厌氧处理中直接种间电子传递的研究进展

直接种间电子传递(DIET)是近年来发现的一种微生物电子传递方式,其在废水厌氧生物处理的重要过程中起重要作用。提高DIET效率能在促进有机物厌氧降解产甲烷的同时储存更多能量,优化厌氧生物处理工艺性能并降低处理成本。本文在DIET过程特性分析的基础上,重点论述了活性炭、生物炭、碳纤维布、单壁碳纳米管4种碳材料对废水生物处理中DIET过程的促进作用,并对今后的研究方向进行了展望。     

环境分权、环境规制对农业面源污染的影响

环境规制是实现农业面源污染减排的重要手段,而科学合理地划分环境管理权力是夯实环境规制减排绩效的制度基础。厘清环境分权、环境规制与农业面源污染三者之间的关系对优化环境管理体制和促进农业绿色发展具有重要的理论与现实意义。鉴于此,文章将环境规制、环境分权和农业面源污染纳入同一分析框架,基于2005—2017年省际面板数据,构建动态面板模型和面板门槛模型,实证考察了环境分权、环境规制与农业面源污染的内在联系。研究结果显示:①环境规制是抑制农业面源污染的重要手段;环境分权、环境监察分权和环境监测分权对农业面源污染具有显著的正向作用,环境行政分权对农业面源污染则表现为负向作用。②环境事务管理权力的下放将恶化环境规制的农业面源污染减排效应,引发“绿色悖论”效应,其中环境监察分权和环境监测分权的影响尤为突出。③从区域层面来看,中西部地区环境事务管理权力下放引发的“绿色悖论”效应显著,而东部地区则不显著。④环境规制对农业面源污染的影响随环境分权程度的变化呈现出门槛特征。伴随环境分权程度的提高,环境规制对农业面源污染的影响由“援助之手”转为“攫取之手”。因此,为解决日益严重的农业面源污染,应制定差异化的环境分权策略。一方面,环境行政权力应适当下放,而环境监察和环境监测权力要逐步上移;另一方面,进一步压缩中西部地区环境政策自由裁量空间,加大农业环境考核与监督力度。同时,建立长期动态农业面源污染监测体系,形成联防联控治理格局。     

固定化甲烷八叠球菌研究—─甲烷八叠球菌富集分离和固定化

用亨盖特（Hungate）厌氧技术,以甲醇为唯一碳源获得了甲烷八叠球菌的富集培养物,以甲醇或乙酸钠（或两者各50％）为碳源滚管培养,获得了以甲烷八叠球菌的分离培养物。用聚乙烯醇（PVA）为包埋剂对甲烷八叠球菌sp固定化,并对其特性进行了研究。结果表明：固定化甲烷八叠球菌与非固定化甲烷八叠球菌的总产气量相似,但两者的产气特性有明显不同。固定化甲烷八叠球菌产气迟于非固定化甲烷八叠球菌,固定化甲烷八叠球菌的产气集中,在产气的6天中,平均日产气量30.88mL甲烷,最高产气量可达2.80mL甲烷/h,在产气高峰两天中的产气量占总产气量的66.0％。非固定化甲烷八叠球菌产气平稳,平均日产气量为8.91mL甲烷。固定化甲烷八叠球菌的电子显微镜观察结果表明,细胞在固定介质中多呈较大包囊存在,包囊直径30～50μm。     

新型的无公害海洋防污涂料

本文概述了海洋防污涂料的发展现状及影响污损生物附着的主要因素,着重论述了低表面自由能材料,吸水性材料的和生化材料等无公害新型防污涂料的防污机制及其试用效果。并指出,开发和应用无锡自抛光涂料和新型低毒防污涂料,这是解决海洋中有机锡污染的近期目标。而刚刚兴起的无公害防污染料尚处在初期研制阶段,其推广应用还需要一个较长时间的发展过程。并且强调应当加强对静,动船舶在苛刻的海洋环境中抗海洋污染生物附着的防污     

铜铬催化剂清洁生产工艺研究

采用清洁生产概念与思维模式,对铜铬催化剂生产全过程进行审核,找出造成其产率低、活性差、污染重的原因及影响因素。以新催化剂研制理论和方法为指导,探讨铜铬催化剂用于糠醇生产过程中提高其产率、活性、原材料利用率以及减轻污染的清洁生产工艺。试验结果表明,在pH为6．2～6．5、Cu／Cr质量比为1：1、反应温度为65℃,活化温度为400℃的条件下,催化剂能获得较高产率和活性。按此新工艺生产的催化剂,产率可提高22％,Cr^6 的排放量可减少95％,活性可提高一倍,废品率可由原来的10％降至零。     

城市河流水域功能合理分类的研究——以第二松花江支流伊通河为例

为提高地方环境标准的科学性与可操作性,本文对我国重点保护水域－第二松花江的支流,流经长春市的伊通河现行过严的功能分类标准提出质疑;并根据第二松花江干流的功能要求和实施流域水污染总量控制的原则,通过预测与计算,提出了伊通河应分河段,跨类别控制的较为科学合理又切实可行的功能分类建议。