二氧化钛/石墨烯复合光催化剂的制备及其对水中双酚A的降解

双酚A污染问题日益严峻,已经威胁到人类的健康.半导体光催化技术可以有效去除水体中双酚A污染.近年来,二氧化钛/石墨烯复合材料,因其优越的光催化性能受到广泛关注.尤其石墨烯等新型纳米碳基材料,有较大的比表面积和丰富的官能团,为二氧化钛的负载创造了良好的条件,其表面可以形成化学键,为双酚A的吸附降解提供了更多的活性位点.本文重点介绍了国内外二氧化钛/石墨烯复合材料的制备方法及各种制备方法的优缺点;讨论了二氧化钛/石墨烯复合材料对双酚A的降解效果及其降解机理;分析了二氧化钛/石墨烯复合材料的再生性能.最后总结这种材料在实际应用中存在的问题及其前景展望.     

Formic acid fractionation towards highly efficient cellulose-derived PdAg bimetallic catalyst for H2 evolution

The present work, in which cellulose isolated from formic acid fractionation(FAC) is decorated with polyetherimide(PEI) to attain highly efficient cellulose-derived PdAgbimetallic catalyst(PdAg-PEI-FAC), has been investigated, and the catalyst properties are characterized by XRD, XPS, BET, ICP-AES and HAADF-STEM. The as-obtained Pd_3.75Ag_3.75-PEI-FAC exhibits excellent catalytic performance for H2 evolution from a sodium formate-free formic acid(FA) aqueous medium at ambient...     

Ceo2/ACFP催化剂低温选择性催化还原NO

采用介质阻挡放电低温氧等离子体技术进行表面改性的活性碳纤维（ACFP）为载体,进行CeO2／ACFP催化剂低温选择性催化还原（SCR）NO的研究。实验结果表明,ACF先经过低温氧等离子体技术进行表面改性后再负载CeO2,能明显提高对NO的去除率。在NO体积分数为1×10^-3、NH3体积分数为2×10^-3、O2体积分数为5％、Ar作为平衡气、反应温度为120—240℃的条件下,较理想的CeO2负载量（质量分数）为9％;在180℃用9％CeO2／ACFP为催化剂时,NO去除率为86．01％。     

负载TiO_2的活性炭纤维改性电极电吸附除氟

采用溶胶-凝胶法制备TiO2凝胶,将TiO2凝胶涂覆在活性炭纤维表面并进行热处理制备改性电极（TiO2/ACF）,利用扫描电子显微镜（SEM）、X射线衍射光谱仪（XRD）、比表面和孔隙度分析仪对负载前后电极的表面特性进行表征,并探讨了其对NaF溶液的电吸附效果。结果表明,电极负载TiO2后表面变得粗糙,比表面积和总孔体积减小,而介孔体积和平均孔径增大。此外,表面的TiO2同时以金红石和锐钛矿的晶型存在。电吸附实验结果显示,加电可以提高吸附容量,而且电压、pH和初始氟离子浓度均对电吸附容量产生影响：电压增大,吸附容量增加,当施加电压为2 V时,电吸附容量为1.03 mg/g,比开路电位时提高40%;pH可以通过影响氟离子在溶液中的存在形态和TiO2/ACF电极表面的羟基基团对电吸附容量产生影响;初始氟离子浓度升高,电极吸附容量增大,但是去除率降低。在处理初始氟离子浓度为4 mg/L的NaF溶液时,在2 V电压、中性pH和12 h的吸附时间下,改性ACF为电极的吸附量为1.32 mg/g。     

关于固体废物污染环境防治法修改的研究思考

2019年6月,《中华人民共和国固体废物污染环境防治法（修订草案）》（以下简称草案）经国务院审议通过,并初次提请全国人大常委会审议。草案修订力度之大,值得充分肯定。同时,草案还存在不少提升空间,需要进一步深入研究。本文以习近平生态文明思想为引领,按照中央全面依法治国委员会第二次会议提出的加强立法统筹、立改废释并举要求,剖析了当前我国固体废物环境管理及其立法修法中面临的挑战,以及存在的突出问题;并从明确固废污染防治立法原则、强化政府统筹管理、明确各部门职责、强化区域统筹、完善跨区域转移监管机制、统筹国内外相关法律法规及政策文件等方面提出了完善草案的建议,以期为我国固废管理决策和草案修改提供参考。     

新型动态膜预涂剂交联聚乙烯醇微球的制备及表征

提出用乳液聚合法制备交联聚乙烯醇(PVA)微球,使其吸附在膜表面实现膜的改性.通过聚乙烯醇(PVA)与戊二醛(GA)的乳化交联试验制备PVA微球粉末,并考察了W/O型乳状液内相的浓度、内外相体积比、乳化剂的性质和含量对形成稳定乳状液的影响.结果表明,当内相PVA水溶液浓度为2.7%、内外相体积比为40∶60、交联剂司盘-80的浓度为1.30 g/dL时,乳状液的稳定性好,形成的交联PVA微球满足需要.在乳化剂浓度足够的前提下,提高乳化机转速,制备的微球的粒径减小.随着理论交联度的提高,微球粒径有变小的趋势,而对Zeta电位影响不大.对制备的微球进行接触角、SEM和FTIR表征,考察了微球的亲水性、表面形态和交联反应对微球官能团的影响.     

Upgrading pyrolytic carbon-blacks (CBp) from end-of-life tires: Characteristics and modification methodologies

• Modification methodologies of upgrading CBp from ELTs were reviewed. • Surface microstructures and physiochemical properties of CBp were analyzed. • Future perspectives of ELTs pyrolysis industries were suggested. Over 1 billion end-of-life tires (ELTs) are generating annually, and 4 billion ELTs are currently abandoned in landfills and stockpiles worldwide, according to the statistics, leading to the environmental and health risks. To circumvent these issues, pyrolysis, as an attractive thermochemical process, has been addressed to tackle the ELTs’ problem to reduce the risks as well as increase the material recycling. However, due to the lack of systematic characteristic analysis and modification methods, poor quality of CBp limits the improvement of ELTs pyrolysis in industry applications, which plays a crucial role in the economic feasibility of pyrolysis process. In this review, we have summarized the state-of-the-art characteristics and modification methodologies of the upgrading of CBp, to in-depth understand the surface microstructures and physiochemical properties of CBp for the foundation for modification afterwards. By virtue of the proper selection of modification methods and modifying agents, the new generation of multifunctional carbon materials with desired properties can be instead of the traditional materials of CB, promising broader and various application fields.     

基于氢火焰离子化检测仪响应因子的设备泄漏排放核算

氢火焰离子化检测仪(FID)是检测设备泄漏挥发性有机物(VOCs)的主要仪器。通过变异系数分析了FID响应因子与FID型号、被测气体种类和被测气体浓度的关系,并进行了实例验证。分析结果表明,FID响应因子与各因素关联强度的排序为:被测气体种类FID型号被测气体浓度。响应因子应用实例的验证结果表明:对于芳烃重整装置145个接触甲苯、二甲苯两组分物料的泄漏设备,响应因子修正后的排放量计算值仅为修正前的18.68%;MTBE装置涉甲醇设备的甲醇排放量计算值修正后为修正前的3倍左右。在此基础上,就设备泄漏VOCs污染源,提出通过响应因子实现排放量精细化核算的建议。     

生物质对水体油污染吸附处理的研究进展

随着石油资源的开发与利用,水体油污染日益严重,寻求价廉、高效、环保的除油方法引起人们的关注,其中吸附法除油效率高,应用范围广,具有很好的发展前景。介绍了水体油污染现状、危害、处理方法,比较了不同类型吸油材料的吸油特性,提出生物质是兼具价廉、环保等多重优点的高效吸油材料。基于此,对生物质吸油材料的选择标准及除油影响因素进行了总结,介绍了常用的吸油机制微观分析方法,并对生物质除油的研究前景进行展望。     

Unintended Cultivation,Shifting Baselines,and Conflict between Objectives for Fisheries and Conservation

The effects of fisheries on marine ecosystems, and their capacity to drive shifts in ecosystem states, have been widely documented. Less well appreciated is that some commercially valuable species respond positively to fishing‐induced ecosystem change and can become important fisheries resources in modified ecosystems. Thus, the ecological effects of one fishery can unintentionally increase the abundance and productivity of other fished species (i.e., cultivate). We reviewed examples of this effect in the peer‐reviewed literature. We found 2 underlying ecosystem drivers of the effect: trophic release of prey species when predators are overfished and habitat change. Key ecological, social, and economic conditions required for one fishery to unintentionally cultivate another include strong top–down control of prey by predators, the value of the new fishery, and the capacity of fishers to adapt to a new fishery. These unintended cultivation effects imply strong trade‐offs between short‐term fishery success and conservation efforts to restore ecosystems toward baseline conditions because goals for fisheries and conservation may be incompatible. Conflicts are likely to be exacerbated if fisheries baselines shift relative to conservation baselines and there is investment in the new fishery. However, in the long‐term, restoration toward ecosystem baselines may often benefit both fishery and conservation goals. Unintended cultivation can be identified and predicted using a combination of time‐series data, dietary studies, models of food webs, and socioeconomic data. Identifying unintended cultivation is necessary for management to set compatible goals for fisheries and conservation. Cultivo Accidental, Líneas de Base Cambiantes y el Conflicto entre los Objetivos para las Pesquerías y la Conservación