区域传输对华东森林及高山背景点位大气污染物浓度的影响

利用HYSPLIT4.8轨迹模式和2011年6月～2012年5月NCEP气象再分析资料计算每日抵达华东森林及高山背景区域的后向气流轨迹并进行聚类,探讨该区域的大气污染物传输特征.同时结合国家大气背景监测福建武夷山站同期大气污染物监测数据,进一步分析不同气团的污染特征及高污染气团的主要来源.结果表明,有65%的轨迹输送污染气块,主要来自我国东部高污染负荷区、江西省以及西北部沙漠地区的高空,有35%的海洋性气团对站点污染物起清除作用,且各气团在各季节对污染物浓度的贡献有一定差异;SO2较高浓度主要受北方城市冬季采暖期燃煤影响,CO较高浓度主要受安徽省煤炭生产和消费过程中的污染物排放影响,NOx、O3、PM10和PM2.5较高浓度主要受我国东部高污染负荷区影响.     

Catalytic wet air oxidation of phenol with functionalized carbon materials as catalysts：Reaction mechanism and pathway

The development of highly active carbon material catalysts in catalytic wet air oxidation（CWAO）has attracted a great deal of attention. In this study different carbon material catalysts（multi-walled carbon nanotubes,carbon fibers and graphite） were developed to enhance the CWAO of phenol in aqueous solution. The functionalized carbon materials exhibited excellent catalytic activity in the CWAO of phenol. After 60 min reaction,the removal of phenol was nearly100% over the functionalized multi-walled carbon,while it was only 14% over the purified multi-walled carbon under the same reaction conditions. Carboxylic acid groups introduced on the surface of the functionalized carbon materials play an important role in the catalytic activity in CWAO. They can promote the production of free radicals,which act as strong oxidants in CWAO. Based on the analysis of the intermediates produced in the CWAO reactions,a new reaction pathway for the CWAO of phenol was proposed in this study. There are some differences between the proposed reaction pathway and that reported in the literature. First,maleic acid is transformed directly into malonic acid. Second,acetic acid is oxidized into an unknown intermediate,which is then oxidized into CO2 and H2O. Finally,formic acid and oxalic acid can mutually interconvert when conditions are favorable.     

城市轨道交通线网规划环评的环境影响要素识别与评价指标体系的建立研究

规划环评的环境影响要素识别和评价指标体系的建立是规划环评分析评价的基础。城市轨道交通线网规划既有战略性、宏观性特点,又有鲜明的行业特征。结合城市轨道交通线网规划环境影响评价的实践对城市轨道交通线网规划环评的环境影响要素识别与评价指标体系的建立进行探讨,使其具有对实际工作的指导意义。     

Preparation of n-Octadecane@MF resin microPCMs and its application in temperature control of esterification reactions

Reaction thermal runaway accidents occur frequently and occupy a high proportion in chemical accidents. Reducing accidents by controlling reaction temperature is of great implication to enhance the safety level of chemical processes. Phase change materials (PCMs) have a good energy storage potential, which can rapidly convert the reaction exotherm in the reaction process into its own phase change latent heat, urgently control the reaction temperature, and enhance the process thermal safety level. In this study, using n-octadecane as the core and melamine-formaldehyde (MF) resin as the shell, microencapsulated phase change materials (microPCMs) was made, which has a smooth spherical shape, good thermal stability, and a phase change enthalpy up to 162.87 J/g. The homogeneous esterification reaction of 2-butanol (2 B) and propionic anhydride (PA) was selected as the target reaction, and then the reaction was scaled up equivalently to investigate the effect of amplification to the reaction system. The results indicated that the temperature control of the esterification reaction system by microPCMs is the synergy between physical inhibition and chemical inhibition. The reaction temperature could be controlled by adding microPCMs, and the temperature control effect improved with the increase of microPCMs addition. In large scale reactors, microPCMs still has certain temperature control ability after being added.     

中国交通运输碳排放及影响因素时空差异分析

为减少交通运输二氧化碳排放量,采用ESDA方法对交通运输碳排放时空分布格局进行研究,同时考虑了空间联系作用,构建GWR模型对碳排放影响因素进行时空差异分析.研究发现:(1)2000—2013年中国省域交通碳排放空间聚类特征随时间变化不大,存在显著的高值、低值聚类特征.京津冀地区、辽宁、山东、山西、陕西、河南地区为高值聚类区,新疆、青海地区一直处于低值聚类区.(2)碳排放影响因素在相邻地区差异较小.其中城镇化率、交通运输结构为主要推动因素,能源强度则起到关键抑制作用.应对碳排放聚类区域施行协同减排目标,同时,应根据因素影响作用差异,分区域制定针对性减排政策.     

功能化多孔材料对CO_2的吸附分离研究进展

功能化多孔材料拥有优越的CO_2吸附和存储性能,在燃煤电厂、玻璃炉窑、水泥厂、钢铁厂等高耗能工矿企业采用CO_2吸附技术,对CO_2减排、减缓温室效应具有重要意义。随着研究的不断深入,新型CO_2吸附材料呈现出廉价、易获取、高吸附率等趋势,当前研究重点集中在介孔硅、金属有机框架、沸石、活性炭、聚合物等的表面功能化。总结了上述典型吸附剂功能化的最新成果,重点介绍多孔吸附材料的功能化方法、吸附机理与吸附动力学的研究进展,并提出多孔材料对CO_2的吸附分离的研究空间和发展趋势。     

我国危险废物转移管理制度研究与讨论

随着社会的发展,危险废物在不同行政区域之间的转移越来越频繁。虽然针对危险废物转移,中国已经制订了相应的管理办法。但仍存在着危险废物转移许可程序不规范、转移手续复杂、转移过程中各相关方责任不清晰等问题,进一步规范和完善我国危险废物转移管理制度已显得十分必要。文章通过对我国危险废物转移管理现状进行分析,展开了相应的研究与讨论。     

Cr(Ⅵ)污染地下水修复的PRB填料实验研究

Fe0与Cr(Ⅵ)发生表层反应使Fe0-渗透反应墙(PRB)利用率极低且易板结、堵塞.针对Fe0利用率低,易板结、堵塞问题,研究了不同高分子材料包裹铁粉对受污染地下水中Cr(Ⅵ)的去除影响;实验结果表明,海藻酸钠(SA)作为包裹材料效果最好.FEI电镜扫描及EDX能谱分析结果表明,SA跟2价金属阳离子Ca2+交联形成孔隙结构,不仅为零价铁的附着提供了大量的吸附点位,还可使Cr(Ⅵ)进入到内部与铁粉反应.考察了SA包裹零价铸铁粉(SAC)和包裹还原铁粉(SAR)对Cr(Ⅵ)的去除影响;实验结果表明,SAC除铬性能是SAR的2倍.SAC填料工艺参数优化后,符合一级反应动力学;采用SAC填料进行动态实验,反应完全后铬/铁比高达32.25 mg.g-1,且填料仍然保持较高的渗透系数(2.38 cm.s-1);对SAC填料进行成本分析发现,SAC填料具有明显的价格优势,相比零价铸铁粉混砂填料节约成本76.56%.采用SAC填料治理Cr(Ⅵ)污染地下水是可行的.     

华东森林及高山背景区域臭氧变化特征及影响因素

为了探讨华东森林及高山背景区域大气中地面O3质量浓度的变化特征,以及相关物质和气象因子对O3生成和变化的影响,选取国家大气背景监测福建武夷山站2011年3月～2012年2月O3为期1 a的监测数据,研究其浓度变化特征和影响因子,并利用后向轨迹模式探讨区域输送对华东森林及高山背景区域O3质量浓度的影响.结果表明,华东森林及高山区域O3背景浓度为(87.9±34.1)μg.m-3;O3浓度具有明显的季节变化特征,春季>秋季>夏季>冬季;与其它气体污染物的相关性分析结果表明,O3来源于远距离水平输送、平流层注入和光化学反应生成;来自高空、长三角地区、珠三角地区气团的输送导致武夷山背景点O3浓度出现极大值.