核-壳结构的Fe-FeOxH2x-3催化UV/H2O2降解腐殖酸

采用硼氢化钠还原法制备了核-壳结构的Fe-FeOxH2x-3纳米复合材料,在近紫外光和H2O2催化条件下,对饮用水消毒副产物前驱体腐殖酸的去除比纳米零价铁的去除高.说明零价铁表面铁氧化物能加速界面电子转移,提高反应效率.探讨了H2O2浓度、腐殖酸初始浓度和起始溶液pH对反应速率的影响.研究结果表明,H2O2最佳投加量为5 mmol·L-1,在pH为5～9时,催化剂都显示了较高的活性;腐殖酸不但被脱色降解,而且TOC去除率达到60%,并且生成的中间产物降低了三氯甲烷的生成趋势.     

降解系统构建菌的原生质体制备及诱变研究

对根际微生物耦合降解系统的两种构建菌株的原生质体形成及再生条件进行研究。结果表明取对数期前期的生长细胞 ,在溶菌酶终浓度为 1mg/mL ,酶解时间为 0 .5h制备的原生质体形成率和再生率均高。在此基础上进行Co6 0 辐射诱变 ,筛选到抗性或营养缺陷型标记菌株共 85株     

河南省洼村粘土矿床地质特征及成因探讨

本文论述了洼村粘土矿床地质特征，成矿模式。根据成矿物质来源等方面研究，认为含矿岩系的物源主要来自碳酸盐岩的红土风化壳。矿床是在海侵过程中风化壳解体，经搬运、沉积、成岩及表生作用形成。     

内循环三相生物流化床启动特性实验研究

本文分别考察了空气流量、水力停留时间、接种污泥浓度及微量元素等因素对内循环三相生物流化床反应器启动挂膜的影响。实验结果表明 ,0 .384L/ min的空气流量对生物膜的培养有利 ;低于 4小时的水力停留时间有利于启动挂膜 ;较少的接种污泥浓度有利于启动挂膜 ,快速排泥的方法能保证反应器启动成功 ;锌及镍等微量元素对反应器启动挂膜影响不大     

福建区域工业三废污染比较研究

福建各地区工业结构、经济发展水平差距较大，工业三废污染对经济、社会发展造成的压力也不尽相同。选取反映工业三废污染及处理的12项主要指标，通过系统聚类分析方法和因子分析方法，分别定量地研究了2000年福建省各地区工业三废污染及处理情况，并分析了原因，进而提出解决的对策。     

活性炭吸附法去除废水中重金属的研究进展

总结了活性炭吸附法去除废水中重金属的机理和规律进行了,其吸附机理有离子交换、络合、化学吸附等,吸附平衡模式除了有Langmuir模式和Freundlich模式之外,还有表面络合模式;分析了pH、溶液的离子强度和初始浓度对单组分溶液吸附去除率的影响;论述了多个金属离子共存时活性炭对金属离子的吸附影响以及金属离子与有机物共存时活性炭对金属离子的吸附影响;最后展望了活性炭在重金属废水处理中的应用前景,提出了一些建议。     

皖北地区乡村稀释化特征、影响因素及形成机制——基于城乡关系的视角

乡村稀释化是指城乡关系失衡下乡村人口持续减少、社会活力凋敝、人居空间不断被稀释的过程,是我国快速城镇化进程中乡村空间问题的动态化呈现,是新时代乡村地理学亟待深化研究的课题。基于城乡关系视角,从人口活力、土地利用和社会活动三个维度对皖北地区乡村稀释化进行测度,综合运用空间自相关、地理加权回归、地理探测器等方法,揭示皖北地区乡村稀释化时空特征、影响因素及形成机制。结果表明：（1）近10年皖北地区乡村稀释化呈现出阶段性加速化过程、多维度差异化状态、集聚性分异化空间格局等特征;（2）人均水资源量、农业从业人口密度、贫困发生率、城乡居民收入差异系数、单位乡村小学在校生人数、每万农村居民村卫生室医生数等要素对皖北地区乡村稀释化影响显著;（3）在特定城乡关系背景下,基于区域本底条件,城市系统的控制引导与乡村系统的被动响应共同推动了乡村稀释化的形成和蔓延。科学认知乡村稀释化,可为乡村振兴与城乡融合发展精准施策提供理论指导。     

2019年5月上海复合污染过程中挥发性有机物的污染特征及来源

本研究基于2019年5月上海市臭氧（O₃）和细颗粒物（PM_2.5）复合污染期间获得的城区大气中挥发性有机物（VOCs）的观测结果,分析了大气中VOCs的污染特征及其与二次生成的关系,同时解析了气团的潜在来源及VOCs的人为源贡献.结果表明,2019年5月上海市O₃与PM_2.5共出现4次污染过程,在平均气温约26℃,相对湿度约40%左右的气象条件下,发生了PM_2.5和O₃同步超标的复合污染现象.VOCs光化学消耗程度与O₃最大净增长量呈现明显的正相关,二次有机气溶胶生成潜势（SOA_P）与PM_2.5日均值呈现明显的正相关.VOCs物种中对臭氧生成有重要贡献的关键活性组分为：间/对-二甲苯、乙烯、甲苯、丙烯和邻-二甲苯等,在臭氧污染日,乙烯和丙烯等关键活性组分的臭氧生成潜势（OFP）百分比贡献进一步加强;对二次有机气溶胶（SOA）有重要贡献的关键活性组分为：甲苯、间/对二甲苯、乙苯、邻-二甲苯和1,2,3-三甲苯,在PM_2.5污染日,甲苯、乙苯、邻-二甲苯和1,3,5-三甲苯等关键活性组分的SOA_P的百分比贡献会进一步加强.     

The dynamic development of bacterial community following long-term weathering of bauxite residue

Bauxite residue is the industrial waste generated from alumina production and commonly deposited in impoundments. These sites are bare of vegetation due to the extreme high salinity and alkalinity, as well as lack of nutrients. However, long term weathering processes could improve residue properties to support the plant establishment. Here we investigate the development of bacterial communities and the geochemical drivers in bauxite residue, using Illumina high-throughput sequencing technology. Long term weathering reduced the pH in bauxite residue and increased its nutrients content. The bacterial community also significantly developed during long term weathering processes. Taxonomic analysis revealed that natural weathering processes encouraged the populations of Proteobacteria, Chloroflexi, Acidobacteria and Planctomycetes, whereas reducing the populations of Firmicutes and Actinobacteria. Redundancy analysis (RDA) indicated that total organic carbon (TOC) was the dominant factors affecting microbial structure. The results have demonstrated that natural weathering processes improved the soil development on the abandoned bauxite residue disposal areas, which also increased our understanding of the correlation between microbial variation and residue properties during natural weathering processes in Bauxite residue disposal areas.     

Vertical distribution of volatile organic compounds conducted by tethered balloon in the Beijing-Tianjin-Hebei region of China

Volatile organic compounds (VOCs) as precursors of ozone and secondary organic aerosols can cause adverse effects on the environment and human health. However, knowledge of the VOC vertical profile in the lower troposphere of major Chinese cities is poorly understood. In this study, tethered balloon flights were conducted over the juncture of Beijing-Tianjin-Hebei in China during the winter of 2016. Thirty-six vertical air samples were collected on selected heavy and light pollution days at altitudes of 50-1000 meters above ground level. On average, the concentration of total VOCs (TVOCs) at 50-100 m was 4.9 times higher than at 900-1000 m (46.9 ppbV vs. 8.0 ppbV). TVOC concentrations changed rapidly from altitudes of 50-100 to 401-500 m, with an average decrease of 72%. With further altitude increase, the TVOC concentration gradually decreased. The xylene/benzene ratios of 34/36 air samples were lower than 1.1, and the benzene/toluene ratios of 34/36 samples were higher than 0.4, indicating the occurrence of aged air mass during the sampling period. Alkenes contributed most in terms of both OH loss rate (39%-71%) and ozone formation potential (40%-72%), followed by aromatics (6%-38%). Finally, the main factors affecting the vertical distributions of VOCs were local source emission and negative dispersion conditions on polluted days. These data could advance our scientific understanding of VOC vertical distribution.