二氧化钛溶胶光催化二氯甲烷溶液的电导率特性研究

利用二氧化钛溶胶进行光催化含氯的有机物.二氯甲烷溶液在二氧化钛溶胶和紫外光的作用下,分解并使得溶液的电导率增加.二氧化钛溶胶的浓度和二氯甲烷的浓度对光催化的电导率的变化有一定的联系.当二氧化钛的浓度过高时,光照所产生的自由基和氧空穴对由于复合、浓度减低,导致二氯甲烷的降解反应速度变缓,反映在电导率的变化上,电导率的增加速度变缓.选择合适的二氧化钛的浓度,将有利于二氯甲烷的光催化分解.     

1,1,2,2-四氯乙烷光催化脱氯的研究

采用TiOSO4为前驱体,制备出比较稳定的纯水性透明TiO2溶胶,该溶胶为中性.利用该TiO2溶胶作为光催化剂对水中微量1,1,2,2-四氯乙烷进行紫外光催化处理.研究发现,1,1,2,2-四氯乙烷在光催化下分解并使溶液的电导率增加,表明在光催化分解下,不断生成氯离子和氢离子,不同的1,1,2,2-四氯乙烷的初始浓度和催化剂的用量等因素对光催化的脱氯的量都有一定的关联.在此实验条件下,固定光照时间,二氧化钛溶胶的浓度在5至10ppm时,光催化的效率达到最大,电导率的变化最大.     

聚酰亚胺和聚苯硫醚耐甲烷氯化物的研究

探究了聚酰亚胺、聚苯硫醚耐甲烷氯化物腐蚀的效果。通过质量变化和液相色谱研究了2种高聚物的耐蚀性。结果表明:聚酰亚胺在二氯甲烷、三氯甲烷中很快被溶解,在四氯甲烷中微量溶解;聚苯硫醚在二氯甲烷中微量溶解,在三氯甲烷、四氯甲烷中有溶胀现象发生。     

锐钛矿型F-TiO2溶胶制备及光催化降解4-氯苯酚的性能

以电解钛丝为前驱物,用过氧化氢溶解-改性水热晶化法制备了锐钛型氟掺杂二氧化钛溶胶.应用XRD、TEM、PSD、UV-vis-DRS,FTIR、XPS技术对溶胶粒子的大小、形貌、晶型、氟的存在形式进行了表征;研究了氟的掺杂量及溶液的pH值对溶胶光催化降解4-氯苯酚性能的影响.结果表明,130℃水热反应15h后生成的TiO2溶胶为纯锐钛型结构,平均粒径为11.0nm;氟分别以吸附态、结合态的形式存在于TiO2粒子的表面和晶格中;氟掺杂后溶胶粒子对4-氯苯酚的吸附能力增大并有利于4-氯苯酚深度矿化.     

金属有机骨架材料MIL-53对氯代甲烷的吸附

采用水热法合成了金属-有机骨架材料MIL-53(Al,Fe,Cr),并用X射线衍射(XRD)、氮气吸/脱附等进行了测试表征。利用固定床吸附试验装置和气相色谱测定了在298K,101kPa时,MIL-53(Al,Fe,Cr)对二氯甲烷、三氯甲烷的吸附情况。结果表明,二氯甲烷比三氯甲烷更易被MIL-53(Al,Fe,Cr)吸附,且MIL-53(Al)对氯代甲烷的吸附能力最强,MIL-53(Cr)次之,MIL-53(Fe)最弱,MIL-53(Al)对二氯甲烷和三氯甲烷的吸附量最高分别可达16.88和7.11mmol/g。实验结果与巨正则系综蒙特卡洛(GCMC)模拟结果一致。     

含氯尾气处理的研究

常温、常压下，用ＮＨ４ＯＨ稀溶液在填料吸收塔中处理任意浓度氯尾气实验；测定了塔顶排出气中含氯小于０．１０×１０－６，塔釜排出液含氯化物（以Ｃｌ－计）１．００ｇ／ＬＨ２Ｏ，游离氯０．２６ｇ／ＬＨ２Ｏ。     

磷酸酯酰氯表面接枝聚乙烯醇的阻燃改性研究

研究（β-氯乙基）磷酸酯酰氯[A]（ClCH2CH2OPOCl2）以三氯甲烷溶液为介质，通过脱HCl发生酯化反应对PVA进行接枝。讨论了阻燃剂浓度、温度、时间、介质等条件对接枝效率的影响，温度降低，接枝率减小，低于50℃时接枝不明显，阻燃剂浓度增大，反应时间延长或引入助溶剂，接枝率提高。热分析研究和剩炭的扫描电镜图分析说明阻燃剂促进PVA的热降解及交联，形成致密的剩炭，起到阻燃作用。     

浅谈脱氯剂在重整循装置中的应用

重整原料中的有机氯经加氢反应后生成hcl而进入到循环氢中，循环氢中hcl的大量积累会对对生产设备、管线及重整催化剂造成严重的危害。鉴于这种危害，脱氯剂应运而生。目前脱氯剂广泛应用于石化领域，对装置防腐和催化剂防中毒起到重要作用。本文简要介绍几种脱氯剂及其应用效果。     

PVC微波低温脱氯非热效应研究

采用效应差异法中相同初末温度比较法,从脱氯率、HCl产率、脱氯半焦特性、能量产率和升温能耗方面对比分析微波加热和常规电加热两种方式下聚氯乙烯(PVC)的脱氯效果,探究PVC微波低温脱氯过程中的非热效应.研究结果表明:相同终温条件下,微波加热与电加热的PVC脱氯效率差别不大,微波加热脱氯效率稍高于电加热;微波加的HCl产率显著高于电加热;除220℃外,电加热脱氯半焦的C和H元素含量稍低于微波加热脱氯半焦,而Cl元素和O元素显著更高;微波加热产生的脱氯半焦的能量产率均高于电加热脱氯半焦.两种热源低温脱氯效果总体上差异较小,因此认为PVC微波低温脱氯过程不存在非热效应,两者之间的差异主要由微波热效应引起.     

纳米二氧化钛的光催化性能研究

采用TiOSO4常温水解法制备纳米二氧化钛，以甲基橙溶液做光催化降解实验，考察各种因素对光催化降解效果的影响。结果表明：加入表面活性剂方式制备的纳米TiO2具有更大的比表面积,光催化降解效果明显；甲基橙溶液的初始浓度越低,光催化降解效果越好；锐钛晶型96．5％、金红石晶型3．5％(质量比)的混晶型纳米TiO2具有更高的光催化活性；进行过多次光催化实验的纳米TiO2经再生后仍然可保持较高的光催化活性。     

钛掺杂有序多孔氧化锆的研究

利用表面活性剂辅助途径,水热条件下合成了含钛的有序多孔氧化锆．通过ＸＲＤ、Ｎ_２吸附、ＨＲＴＥＭ、ＵＶ－ＶＩＳ吸收光谱、Ｒａｍａｎ光谱等手段对不同按量的钛掺杂多孔氧化锆进行研究．结果表明,＜１５ｍｏｌ％的钛掺杂有利于提高材料的比表面积;钛掺量＜３０ｍｏｌ％时,钛能很好进入氧化锆骨架中,但随着掺量增加,孔道有序性降低．掺量＞３０ｍｏｌ％,多余的钛将以纳米晶ＴｉＯ_２形式析出．     

Microstructure and mechanical properties of spark plasma sintered titanium‐added copper/reduced graphene oxide composites

Copper matrix composites were fabricated through mixing fixed amount of reduced graphene oxide and the different amounts of titanium. The dried copper/titanium/reduced graphene oxide mixture powders were firstly obtained by the wet‐mixing process, and then the spark plasma sintering process realized their faster densification. In the as‐sintered bulk composites, the layered reduced graphene oxide network, uniform titanium particles and copper‐titanium solid solution are observed in copper matrix. Investigations on mechanical properties show that the as‐prepared bulk composites exhibit the hardness and compressive yield strength compared with single reduced graphene oxide added composites. Increased titanium addition resulted into higher hardness and strength. The relevant formation and failure mechanisms of the composites and their influence on mechanical properties were discussed.     

柔性聚苯胺电极体积电容的提高:溶液浇铸法以及还原氧化石墨烯的影响

高体积比电容是柔性超级电容器的关键.在本文中,我们设计并制备了一种具有超高体积比电容和良好倍率性能的柔性复合电极.该膜电极以无孔且致密的聚苯胺作为基质,少量的还原氧化石墨烯片作为填料,通过一种新开发的溶液浇铸法制备而成.用于浇铸的溶液是由聚苯胺和氧化石墨烯的混合溶液自组装制备得到.关于还原氧化石墨烯作用的系统研究结果表...     

The influence of surfactants on the roughness of titania sol–gel films

Substrate dipping in a composite sol–gel solution was used to prepare both smooth and rough thin films of titanium dioxide (TiO₂) on commercial fiberglass. The deposition of a composite film was done in a beaker using a solution of titanium (IV) isopropoxide as the sol–gel precursor and cetyltrimethyl ammonium bromide as the surfactant. In order to establish a correlation between experimental conditions and the titanium oxide produced, as well as the film quality, the calcined samples were characterized using Raman spectroscopy, UV–vis spectrophotometry, scanning electron microscopy and atomic force microscopy. One of the most important results is that a 61-nm TiO₂ film was obtained with a short immersion of fiberglass into the sol–gel without surfactant. In other cases, the deposited film consisted of a titanium precursor gel encapsulating micelles of surfactant. The gel films were converted to only the anatase phase by calcining them at 500 °C. The resulting films were crystalline and exhibited a uniform surface topography. In the present paper, it was found that the TiO₂ films prepared from the sol–gel with a surfactant showed a granular microstructure, and are composed of irregular particles between 1.5 and 3 μm. Smooth TiO₂ films could have useful optical and corrosion-protective properties and, on other hand, roughness on the TiO₂ films can enhance the inherent photocatalytic activity.     

双组元掺杂钛硅再结晶石墨传导性能的研究

用煅烧石油焦作填料,煤沥青作粘结剂,钛粉和硅粉作添加剂,采用热压工艺制备了一系列双组元掺杂再结晶石墨.考察了不同质量配比的添加剂对再结晶石墨的热导率、电阻率和抗弯强度的影响以及微观结构的变化.实验结果表明,与相同工艺条件下制备的纯石墨材料相比较,掺杂15wt％钛粉再结晶石墨的传导以及力学性能有较大幅度的提高.在掺杂钛粉15wt％、硅粉<2wt％时,双组元再结晶石墨的常温热导率随着硅粉的掺杂量的增加有所提高.当掺杂钛粉及硅粉分别为15wt％和2wt％时,再结晶石墨RG-TiSi-152的常温热导率可达494W/m·K.但是当掺杂钛粉15wt％、硅粉>2wt％时,随着硅粉的继续增加,再结晶石墨的常温热导率反而降低.而双组元掺杂钛硅再结晶石墨的导电以及力学性能却随着硅粉的掺杂量的增加而降低.XRD分析表明,对于双组元掺杂钛硅再结晶石墨而言,钛元素最终在材料中以碳化钛形式存在,而硅元素则大都以气态形式被逸出,XRD物相图谱中未发现硅及其碳化物的存在.材料RG-TiSi-152的微晶尺寸La以及晶面层间距d₀₀₂分别为864和0.3355nm.     

Role of binder in the synthesis of titania membrane

The synthesis of titania membrane through sol-gel route involves hydrolysis of alkoxide peptization of hydrous oxide of titanium to obtain a sol, adjustment of the sol viscosity by including a binder and filtration of the viscous sol through a microporous support, gelation and sintering to desired temperature. The binder plays an important role in that it not only helps in adjustment of sol viscosity but also helps in binding the sol particle with porous support. Here a comparative study on the role of different binders, viz. polyvinyl alcohol, polyethyleneimine, polyacrylamide, effect of their viscosity and surface tension effect on the morphology of the titania membrane is presented. The results show that among the three binders studied polyvinyl alcohol gave rise to membranes of desired characteristics when the sol viscosity was 0.08 pa.s.     

Amount of hydroxyl radical on calcium-ion-implanted titanium and point of zero charge of constituent oxide of the surface-modified layer

To compare the surface properties of calcium-ion (Ca2+)-implanted titanium with those of titanium and to investigate the mechanism of bone conductivity of Ca2+-implanted titanium, amounts of hydroxyl radical of Ca2+-implanted titanium and titanium were estimated. Also, the point of zero charge (p.z.c.) of oxide constituting surface oxides of Ca2+-implanted titanium and titanium was determined. Results showed that the amount of active hydroxyl radical on Ca2+-implanted titanium was found to be significantly larger than that on titanium, indicating that the number of electric-charging sites of Ca2+-implanted titanium in electrolyte is more than that of titanium. The p.z.c. values of rutile (TiO2), anatase (TiO2), and perovskite (CaTiO3), were estimated to be 4.6, 5.9, and 8.1, respectively. Thus, Ca2+-implanted titanium surface is charged more positively in bioliquid than titanium, accelerating the adsorption of phosphate ions. © 1998 Chapman & Hall     

Effect of aluminum oxide doping on the structural,electrical, and optical properties of zinc oxide (AOZO) nanofibers synthesized by electrospinning

Zinc oxide nanofibers doped with aluminum oxide were prepared by sol–gel processing and electrospinning techniques using polyvinylpyrrolidone (PVP), zinc acetate and aluminum acetate as precursors. The resulting nanofibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–Vis spectroscopy, and current–voltage (I–V) properties. The nanofibers had diameters in the range of 60–150 nm. The incorporation of aluminum oxide resulted in a decrease in the crystallite sizes of the zinc oxide nanofibers. Aluminum oxide doped zinc oxide (AOZO) nanofibers exhibited lower bandgap energies compared to undoped zinc oxide nanofibers. However, as the aluminum content (Al/(Al + Zn) × 100%) was increased from 1.70 at.% to 3.20 at.% in the electrospinning solution, the bandgap energy increased resulting in lower conductivity. The electrical conductivity of the AOZO samples was found to depend on the amount of aluminum dopant in the matrix as reflected in the changes in oxidation state elucidated from XPS data. Electrospinning was found to be a productive, simple, and easy method for tuning the bandgap energy and conductivity of zinc oxide semiconducting nanofibers.