竹炭和猪炭对空心菜-小青菜轮作土壤N2O和CO2排放的影响

以动物源的猪炭和植物源的竹炭为试验材料,通过田间小区试验,研究生物质炭的种类(竹炭和猪炭)、施用方式(一次施用和分批施用)对空心菜-小青菜轮作土壤N_2O和CO_2排放的影响,结果表明:空心菜季土壤N_2O和CO_2排放显著高于小青菜季,土壤N_2O和CO_2排放与土壤pH、温度呈显著相关(p0.01).与不施炭对照相比,竹炭处理可使两季空心菜和小青菜土壤N_2O累积排放量减少16.9%~39.9%,同时CO_2排放量减少9.2%~15.7%,且一次施用处理优于分批施用.猪炭处理在土壤N_2O减排效果上没有竹炭显著,且一次性施用猪炭处理明显增加了两茬空心菜土壤CO_2排放量,与对照相比,分别增加了13.3%和12.9%.与猪炭相比,一次性施用20 t·hm~(-2)竹炭处理在抑制土壤N_2O和CO_2排放上效果更佳.     

Exploration of the key functional strains from an azo dye degradation microbial community by DGGE and high-throughput sequencing technology

Environmental Science and Pollution Research - This study investigated a previously developed thermophilic microbial community with the ability to effectively degrade azo dyes. To identify the key...     

Study on the influencing factors of peasants’ subjective well-being

On the basis of data collected from Liupanshan poverty-ridden areas, the paper selects 24 variables under 4 groups to figure out the influencing factors of subjective well-being (SWB) of peasants in ecological migration with the method of Ordered Probit Regression. As is shown in the results, variables under peasants’ personal endowment group and resource of the development group have little impact on peasants’ SWB. The variables with observable impact are concentrated in the living condition group and the public atmosphere group.     

Separation and characterization of magnetic fractions from waste-to-energy bottom ash with an emphasis on the leachability of heavy metals

Environmental Science and Pollution Research - Magnetic fractions were extracted from pulverized waste-to-energy (WTE) bottom ashes using a combined wet-dry extraction method. The resulting...     

The explosion overpressure field and flame propagation of methane/air and methane/coal dust/air mixtures

The explosion of the methane/air mixture and the methane/coal dust/air mixture under 40 J center spark ignition condition was experimentally studied in a large-scale system of 10 m³ vessel. Five pressure sensors were arranged in space with different distances from the ignition point. A high-speed camera system was used to record the growth of the flame. The maximum overpressure of the methane/air mixture appeared at 0.75 m away from the ignition point; the thickness of the flame was about 10 mm and the propagation speed of the flame fluctuated around 2.5 m/s with the methane concentration of 9.5%. The maximum overpressure of the methane/coal dust/air mixture appeared at 0.5 m. The flame had a structure of three concentric zones from outside were the red zone, the yellow illuminating zone and the bright white illuminating zone respectively; the thickness and the propagation speed of the flame increased gradually, the thickness of red zone and yellow illuminating zone reached 3.5 cm and 1 cm, the speed reached 9.2 m/s at 28 ms.     

Partial nitritation of landfill leachate with varying influent composition under intermittent aeration conditions

The start-up and operation of a partial nitritation sequencing batch reactor for the treatment of landfill leachate were carried out on intermittent aeration mode. Partial nitrite accumulation was established in 15 days after the mode was changed from continuous aeration to intermittent aeration. Despite the varying influent composition, partial nitritation could be maintained by adjusting the hydraulic retention time (HRT) and the air flow rate. An increase in the air flow rate together with a decrease in air off duration can improve the partial nitritation capacity and eventually result in the development of granular sludge with fine diameters. A nitrogen loading rate of 0.71 ± 0.14 kg/m³/d and a COD removal rate of 2.21 ± 0.13 kg/m³/d were achieved under the conditions of an air flow rate of 19.36 ± 1.71 m³ air/m³/h and an air on/off duration of 1.5 min/0.7 min. When the ratio of total air flux (TAF) to the influent loading rate (ILR) was controlled at the range of 163–256 m³ air/kg COD, a stable effluent NO₃^?–N/NO_x^?–N (NO₂^?–N plus NO₃^?–N) ratio below 13% was achieved. Interestingly, the effluent pH was found to be a good indicator of the effluent NO₂^?–N/NH₄⁺–N ratio, which is an essential parameter for a subsequent anaerobic ammonium oxidation (Anammox) reactor.     

四川城市水灾的历史特征

本文以2000多年的历史资料为基础,对四川城市水灾的规律进行了考察分析,认为有着明显的特征。即普遍性、周期性、季节性和区域性。并指出上述特征对于防洪减灾工作的有利条件和不利影响。     

安徽省工业危险废物产生现状与产量预测研究

近些年,随着安徽省正式加入长三角地区,化学工业和电子信息产业的发展,工业危险废物种类和数量均有显著增加.依据2011年-2014年安徽省统计年鉴中的工业危险废物产生量和综合利用量的统计数据,分析了安徽省工业危险废物类别及产业分布特点,并建立GM模型对未来几年危险废物产生的动态变化进行预测.同时分析了安徽省危险废物管理存在的一些问题,最后提出了相关的污染防治对策.     

绿色机场垃圾资源化处理流程设计

绿色机场是今后机场建设与运营的发展趋势,机场垃圾处理是绿色机场建设与运营的重要组成部分。分析了中国机场垃圾处理现状,结合机场垃圾的组分及特点,提出了一种资源化综合处理模式,根据“无害化、减量化、资源化”的原则设计了绿色机场垃圾资源化处理流程。为提高分选效率,采用多种组合工艺进行机场垃圾的分选,分离出的塑料、纸张和金属等直接回收利用,有机物采用水热氧化技术进行制肥,可燃物制成垃圾衍生燃料（RDF）,危险废弃物单独处理,少量剩余残渣填埋。该处理流程合理可行,实施性好,能产生较好的社会、经济和环境综合效益。     

等离子体协同MnOx/SBA-15催化降解正己醛的研究

采用浸渍法制备了MnOx/SBA-15催化剂,利用BET、XRD和SEM等对催化剂进行表征。考察了介质阻挡放电等离子体协同MnOx/SBA-15催化剂对正己醛的降解性能。结果显示,负载MnOx后的SBA-15仍然保持介孔结构,且MnOx均匀地分散在SBA-15中;等离子体与催化剂表现出较好的协同作用,干燥条件下7.5 kV的放电电压结合10%MnOx/SBA-15时降解效果最佳,正己醛去除率达99%;相比干燥条件,相对湿度低于20%时正己醛去除率变化不明显,但高于20%时催化效果明显下降;该催化剂具有很强的O3分解能力,O3在催化剂表面的分解不仅促进了正己醛的氧化,同时也提高了CO2的选择性。