External mass transfer during the adsorption of various pollutants onto activated carbon

A wide range of experimental studies are reported for the adsorption of phenol and p-chlorophenol onto activated carbon—Type Filtrasorb 400—in an agitated batch adsorber. A model has been used to determine the external mass transfer coefficient for the systems and the effect of several experimental variables have been investigated: these include agitation, initial pollutant concentration, carbon mass, carbon particle size and solution temperature. The mass transfer coefficient has been correlated in terms of the dimensionless Sh/Sc^0.33 against each variable. The Sherwood number, Sh = k_fR/D_mol, relates the external mass transfer coefficient k_f to particle radius, R, and molecular diffusivity, D_mol. The Schmidt number, Sc, is the ratio of kinematic viscosity, v, to molecular diffusivity. A few results are also reported for the adsorption of sodium dodecyl sulphate and mercuric ions onto activated carbon.     

油脂环氧化装置火灾危险性及防火设计

针对油脂环氧化装置的工艺流程及火灾危险性进行分析.探讨了油脂环氧化装置的潜在事故风险与事故发展模式,针对反应釜爆炸的发展模式提出防火安全设计应注意的问题及适用于油脂环氧化装置的防火设计对策.     

掺合料对低温混凝土孔径分布的影响

目的 针对低温条件下东北地区施工特点,研究了在不掺防冻剂的情况下,不同掺合料对C30幼龄期混凝土孔径分布的影响.方法：采用压汞法测试了在恒低温一次冻结和自然变低温多次冻结养护情况下幼龄期混凝土的孔径分布情况.结论：掺合料可以改善低温混凝土的内部结构,减少多害孔和有害孔的比例,提高少害孔和无害孔的比例;混凝土在恒低温-10℃养护条件下较之变低温-15℃～5℃养护条件下有害孔和多害孔所占比例高,少害孔和无害孔所占比例低.     

不同养护条件下水泥基材料的孔隙结构

对于不同水胶比的水泥基材料,使用压汞法研究了其在饱水养护和密封养护条件下孔隙结构的特征.结果表明：养护条件对水泥基材料的孔径分布影响明显.与饱水养护相比,密封养护能显著增加RⅢ区间（100～1000nm）的孔隙含量(质量体积),降低RⅠ区间（<10nm）的孔隙含量;密封养护会降低水泥基材料的比表面积,增加净浆的孔隙率(体积分数),但对砂浆孔隙率的影响较不明显.胶凝材料中的磨细高炉矿渣(质量分数为65%）和硅粉(质量分数为5%）不能完全抑制孔隙自干燥导致的孔隙连通作用.     

H3PW12O40-TiO2/膨润土光催化降解甲基橙的催化性能

通过溶胶凝胶制得H3PW12O40Ti(OH)4凝胶,并柱撑于膨润土层间制备了复合光催化剂H3PW12O40TiO2/膨润土。由XRD、SEM、EDS对制备的复合光催化剂进行表征测试表明,固载的H3PW12O40TiO2使膨润土层状结构发生明显变化,柱撑体H3PW12O40TiO2呈弥散状态,且TiO2为锐钛结构,催化剂为颗粒粒径大小不一、分布松散的复合材料。对甲基橙的H3PW12O40TiO2/膨润土光催化降解应用表明,掺杂的杂多酸使所制备的复合催化剂光催化活性得到了极大提高,在光催化体系下有较广的pH适应范围,且制备的催化剂具有良好的催化稳定性。在表征分析及应用实验的基础上,提出了H3PW12O40TiO2/膨润土的强化催化作用原理。     

聚合物干粉对加气混凝土用抹灰砂浆性能的影响

针对加气混凝土普通抹灰砂浆存在的保水性差、粘结强度低、易开裂空鼓等缺陷,研究了聚合物干粉对加气混凝土用抹灰砂浆性能的影响,并对该影响机理进行了讨论.研究表明,在砂浆中同时掺入羟乙基甲基纤维素醚和聚乙烯-醋酸乙烯酯可再分散乳胶粉,大大改善了砂浆的保水性、提高了和易性和粘结强度,较好地解决了普通抹灰砂浆用于加气混凝土存在的开裂、空鼓甚至脱落等问题.     

烟气脱汞技术研究现状与展望

重金属汞的危害性决定了烟气脱汞的必要性,尤其在污染物超低排放的背景下。首先分别从常规烟气净化装置脱汞、碳基吸附剂脱汞、矿物类吸附剂脱汞以及金属催化剂脱汞等四个方面综述了烟气脱汞技术研究现状,重点讨论了各种烟气脱汞技术特点以及吸附剂改性的反应机理。最后,分别从协同脱汞、纳米吸附剂脱汞以及可再生脱汞等三个方面对未来脱汞技术进行了展望,该三个方面主要分别涉及了多污染物控制排放、提高脱汞效率以及降低脱汞技术应用成本。期望为烟气脱汞技术的进一步开发与应用提供参考。     

Electroactive phases of poly(vinylidene fluoride): Determination,processing and applications

Poly(vinylidene fluoride), PVDF, and its copolymers are the family of polymers with the highest dielectric constant and electroactive response, including piezoelectric, pyroelectric and ferroelectric effects. The electroactive properties are increasingly important in a wide range of applications such as in biomedicine, energy generation and storage, monitoring and control, and include the development of sensors and actuators, separator and filtration membranes and smart scaffolds, among others. For many of these applications the polymer should be in one of its electroactive phases. This review presents the developments and summarizes the main characteristics of the electroactive phases of PVDF and copolymers, indicates the different processing strategies as well as the way in which the phase content is identified and quantified. Additionally, recent advances in the development of electroactive composites allowing novel effects, such as magnetoelectric responses, and opening new applications areas are presented. Finally, some of the more interesting potential applications and processing challenges are discussed.