Preparation and Characterization of High Reflectance Titanium Powders

通过分析颜料光学性质、形貌和粒径与热反射比的关系,制备了一种对波长范围为400~2500 nm的光具有较高反射比的球形二氧化钛粉体材料。通过粉体的X射线衍射分析、扫描电镜成像、动态激光散射粒度分析等表征,证实粉体晶型为金红石型,粒径较好的分布在200~1250 nm,经紫外-可见-近红外分光光度计检测,其反射比均优于市售钛白,其中所制备的1.228μm球形二氧化钛粉体具有最好的反射比。Based on the analysis of the relationship between the light reflectance and pigment optical properties, morphology, particle size distribution, the spherical TiO2 powders with high reflectance were prepared. Through the X-ray diffraction, scanning electron microscope imaging, and dynamic laser scattering particle size analysis, it was confirmed that the TiO2 powders were all in the form of rutile type and sphere with 200 - 1250 nm in. size. The test results using ultraviolet-visible-near infrared spectrophotometer revealed that all the as-prepared TiO2 particles were superior to the commercial titanium white, and the one with 1. 228 μm size was the best among them.新疆维吾尔自治区自然科学基金项目（2015211A004）

均四甲苯氧化制二酐宏观动力学分析

为了提高均四甲苯氧化制均苯四甲酸二酐的收率,以某二酐生产企业生产的高效钒钛催化剂,在固定床反应器中对均四甲苯气相氧化制均苯四甲酸二酐反应体系的动力学进行了研究。首先提出了可能的反应网络,然后设计相关动力学测试实验,建立均四甲苯氧化反应的幂函数宏观动力学模型。进一步的实验和统计分析表明,模型计算值与实验值吻合较好。宏观动力学方程的建立为后续将其用于相应的固定床反应器模拟提供了基础保证。新疆维吾尔自治区自然科学基金项目(2015211A004)资

Research on Anticorrosive Property of Polyaniline

利用化学氧化聚合法合成了分散性好的本征态聚苯胺(Eb),然后用SEM(扫描电子显微镜)、uV-VIS(紫外可见分光光度计)、fT-Ir(傅里叶转换红外线光谱分析仪)、Xrd(X射线衍射仪)、Tg(热重分析仪)等表征测试手段对样品进行了分析研究。同时利用盐雾实验和电化学测试监测了本征态聚苯胺对有机涂层耐蚀性能的影响。结果表明:此方法合成的本征态聚苯胺在0.8%(质量分数)的添加量时即能使有机涂层的耐蚀性能得到极大的提高

Ru和Cu协同催化湿式氧化处理氨氮废水

采用化学还原法制备了RuCu/TiO2双金属催化剂,并探究了Ru和Cu的协同作用对催化湿式氧化（CWAO）无害化处理氨氮废水催化性能的影响。研究结果表明,Cu的添加可有效改善Ru/TiO2催化剂的N2选择性,而Ru的存在可有效提高Cu/TiO2催化剂的催化活性。反应条件为0.5 MPa、150℃、[NH3]0=1000 mg·L-1、pH=12、模拟废水处理量为33 L·（kg cat）-1·h-1时,1Ru2Cu/TiO2能使废水的氨氮转化率和N2选择性分别高达87.7%和85.9%。表征结果表明:Ru和Cu的协同在催化氧化氨氮废水过程中起了关键作用,主要体现在:Ru和Cu的强相互作用导致1Ru2Cu/TiO2催化剂具有良好的抗流失性能,进而使得催化剂具有良好的稳定性;Ru和Cu的电子转移使得1Ru2Cu/TiO2具有适中的亲氧性能,有效提高了催化剂的催化活性。新疆维吾尔自治区高校科研计划项目(XJEDU2016S083);;福建省自然科学基金项目(2015J05031)~

烧结板布风的甲烷化流化床反应器建模与分析

以烧结板型气体分布器的甲烷化流化床反应器为研究对象,在ANSYS-FLUENT平台中利用用户自定义函数建立了烧结板型气体分布器的数学模型;并对过程反应动力学模型提出了合理的改进,在宏观上实现反应速率与催化剂浓度的正相关。通过模型的计算结果与实验数据对比验证了模型的有效性,在模拟结果的基础上对烧结板型气体分布器的甲烷化流化床反应器的参数分布进行了分析。结果表明:烧结板模型的引入可增强反应器入口边界描述的精确性,对反应动力学模型的合理改进可更好地反映甲烷化反应过程,提高了计算的精确性。国家自然科学基金(21576228

烧结板布风的甲烷化流化床反应器建模与分析

采用双流体模型对烧结板型气体分布器的甲烷化流化床反应器进行数值模拟,在ANSYS-FLUENT平台中利用用户自定义函数建立了烧结板型气体分布器的数学模型;并对过程反应动力学模型进行改进,在宏观上实现了反应速率与催化剂浓度的正相关;通过模型的计算结果与实验数据对比验证了模型的有效性.在模拟结果的基础上对烧结板型气体分布器的甲烷化流化床反应器的参数分布进行了分析,结果表明:烧结板模型的引入增强了反应器进口边界描述的精确性,对反应动力学模型的合理改进更好地反映了甲烷化反应过程,并更符合实验结果,从而提高了模拟计算的精确性.国家自然科学基金(21576228

Ternary Alloy Electrocatalysts for Oxygen Reduction Reaction

质子交换膜燃料电池作为重要的电化学能源转换装置,在提高能量转换效率、减少环境污染等方面具有诱人的前景.然而,阴极氧还原过电位较大、活性较低、稳定性差,且铂基催化剂昂贵,使该燃料电池难以商业化.纳米结构电催化剂的发展有望解决此难题.对纳米合金电催化剂其组分和结构的设计是开发高活性、高稳定性和低成本的燃料电池电催化剂的重要因素.本文综述了近期由分子设计和热化学控制处理法制备的三元纳米合金电催化剂对燃料电池氧还原反应催化性能的最新进展.该方法可控制纳米合金的尺寸、组成以及二元和三元纳米催化剂的合金化程度.以高活性的三元纳米合金催化剂PTnICO/C为例,综述了在设计燃料电池电催化剂时结构和组成的纳米级调优的重要性.PTnICO/C电催化剂的质量比活性远高于其二元合金催化剂和PT/C商业电催化剂.三元电催化剂的催化活性可通过控制其组成来调节.本文还讨论了三元纳米合金催化剂的结构及其协同效应对增强其电催化性能的影响.Proton exchange membrane fuel cell represents an important electrochemical energy conversion device with many attractive features in terms of efficiency of energy conversion and minimization of environmental pollution.However,the large overpotential for oxygen reduction reaction at the cathode and the low activity,poor durability and high cost of platinum-based catalysts in the fuel cells constitute a focal point of major barriers to the commercialization of fuel cells.The development of nanostructured catalysts shows promises to addresses some of the challenging problems.The ability to engineer the composition and nanostructure of nanoalloy catalysts is important for developing active,robust and low-cost catalysts for fuel cell applications.This article highlights some of the recent insights into the catalytic properties of ternary nanoalloy catalysts prepared by molecularly-engineered synthesis and thermochemically-controlled processing,focusing on oxygen reduction reaction in fuel cells.This approach has demonstrated the abilities to control size,composition,and nanoscale alloying of binary and ternary nanoalloys.A highly-active ternary nanoalloy catalyst consisting of platinum,nickel and cobalt that is supported on carbon(PtNiCo/C) will be discussed as an example,highlighting the importance of nanoscale tuning of structures and composition for the design of fuel cell catalysts.The mass activity of selected PtNiCo/C catalysts has been shown much higher electrocatalytic activity than those observed for their binary counterparts and commercial Pt/C catalysts.Selected examples will also be shown that the catalytic activity can be tuned by the ternary composition.The structural and synergistic properties of the ternary nanoalloy catalysts for the enhancement of the electrocatalytic activity will also be discussed.supportedbyNationalScienceFoundation(CBET-0709113andCHE-0848701);DepartmentofEnergy;Honda;andUTCPowe

Preparation of nano-TiO_2 with high reflectance

采用溶胶-凝胶法制备纳米TIO2,利用紫外-可见-近红外分光光度计测定样品在400--2500 nM的反射率。系统研究了制备条件对样品反射率的影响,并确定了最佳制备条件。所制备的纳米TIO2粉体的平均反射率大于110%,明显高于市售的太阳热反射粉,该粉体能够作为良好的太阳热反射涂料颜填料。Nano-TiO2 were prepared with sol-gel method,and the reflectance of nano-TiO2 in the range of 400-2500 nm was determined by UV-VIS-NIR spectrophotometer.The effects of preparating conditions on reflectance were systematically investigated,and the optimum preparating conditions were obtained.The average reflectance of nano-TiO2 was larger than 110%,aparently higher than that of the marketable solar reflective powders.This powder can be used as good fillers in solar reflective coatings.福建省自然科学基金(2009J05036)资

合成气甲烷化过程模拟与分析

针对合成气甲烷化反应,基于吉布斯自由能最小法的热力学模型对反应过程进行了热力学分析,考察了温度、压力、水分对反应过程的影响。基于Ni-ZrO2催化剂和固定床进行了合成气甲烷化实验,根...新疆维吾尔自治区高校科研计划(XJEDU2016S083

Effect of Ag loading on soot oxidation for Ag/Ce_(0.75)Zr_(0.25)O_2 catalysts

开发低温下高催化活性的柴油机碳烟颗粒燃烧催化剂是当前环境催化领域的热点问题。利用共沉淀的方法制备了用于碳烟催化燃烧反应的Ag/Ce_(0.75); Zr_(0.25)O_2催化剂。活性评价结果表明,相对于Ce_(0.75)Zr_(0.25)O_2催化剂,Ag的引入可显著降低碳烟催化燃烧温度。; 而且,Ag的负载量存在一个最佳值。以XRD、in-situ; XRD、BET、TPR等表征手段探究了该系列催化剂结构性质及其变化产生的影响。结果表明,Ag与Ce物种间的相互作用可显著降低催化剂(特别是CeO; _2表面氧)的还原温度。该相互作用使Ag/Ce_(0.75)Zr_(0.25)O_2催化剂在一定温度下(>200℃)就表现出Ag+的性质。这些性; 质与该催化剂具有较高的碳烟氧化活性相关。而且,该催化剂也表现出良好的稳定性。It is still important to develop soot oxidation catalysts with excellent; activity under low temperature. Ag/Ce_(0.75)Zr_(0.25)O_2 was synthesized; via coprecipitation method for soot oxidation. Compared with the; catalytic performance of Ce_(0.75)Zr_(0.25)O_2, the introduction of Ag; can lead to the decrease of soot-ignition temperature. Moreover, there; is an optimal Ag loading. Subsequently, several methods such as XRD,; in-situ XRD, BET, TPR were used to characterize the physicochemical; properties of Ag-based catalysts. The results showed that the; introduction of Ag resulted in decreasing the reduction temperature of; surface oxygen species, being due to the interaction of Ag and Ce. The; interaction also brings about the occurrence of Ag~+ nature. And the; feature is linked with the outstanding activity of soot oxidation for; Ag-based catalyst. Furthermore, the Ag-based catalyst possessed fairly; good stability in soot oxidation.国家自然科学基金项目; 中央高校基本科研业务费专项资金项