纳米硫化镉的制备、表征及其光催化性能研究

以CdCl2和Na2S为主要原料，制备了纳米CdS颗粒，通过X射线衍射（XRD）和扫描电镜（SEM）分析其晶型和粒径，通过紫外-可见漫反射的表征，计算其带隙能，并用BET法测定其比表面积．通过对CdS固体的红外光谱的分析，研究颗粒的表面状况。将制备的纳米CdS颗粒用于亚甲基蓝的光催化降解反应，通过空白实验和暗反应实验的对比证明，自制的纳米CdS颗粒具有良好的光催化性能．最后还通过多次实验证明了自制Cds具有持久的光催化寿命．     

一锅煮法制备硫化镉和碲化镉纳米晶及其性能表征

以三辛基膦为配位溶剂,采用一锅煮的方法制备出分散性较好的硫化镉和碲化镉纳米晶,通过改变反应温度和硫前驱体可制备出不同形貌和结构的硫化镉纳米晶。用此方法也可制备出碲化镉网状纳米晶。测试结果表明,这两种纳米晶都具有较好的晶型。     

氧化锌铝(ZAO)陶瓷靶材制备及其薄膜性能

溶胶-凝胶方法制备的ZnO和Al2O3混合粉末经冷压预成型加真空低压烧结,制备了高致密度(相对密度99%)、低成本的ZAO陶瓷靶材.研究了ZAO靶材与无氧铜的粘接性能.用中频交流磁控溅射ZAO靶材的工艺制备了ZAO薄膜.利用SEM和XRD分析测试了陶瓷靶材断口形貌以及靶材和薄膜的结构.试验结果表明制得的ZAO靶材具有良好的粘接性和溅射性能,内部组织致密,靶材中有明显的ZnAl2O4相.在优化沉积工艺条件下,制备的ZAO薄膜方块电阻为35 Ω,电阻率可达3.84×10-4 Ω·cm,可见光透过率(λ=550 nm)可达91.1%.沉积态的ZAO薄膜具有很好的结晶性,并呈现(002)择优取向.ZAO薄膜有明显的紫外吸收限,带隙Eg约为3.76 eV.ZAO靶材的工业化磁控镀膜试验也取得了较好的结果.     

多孔陶瓷支撑体膜材料的制备与性能表征

研究了α－Ａｌ２Ｏ３多孔陶瓷的性能与起分的粒径、成孔剂的用量等因素的关系，取得了一些规律性的认识，开发了以有机聚合物先驱物挤压成型工艺，在成功地制备出具有实用价值的单通道和多道的管状支撑体陶瓷膜，研究了烧成制度对性能的影响，测定了管膜的孔径颁孔隙率、透气和爱水性以及机械强度 。     

磁性陶瓷靶材的制备及其应用研究

薄膜制备过程中溅射靶材的利用率很低,导致薄膜材料制备成本很高。以自制的高纯度纳米晶镍钴锌/二氧化硅复合铁氧体粉体为原料,冷等静压后高温烧结制备得到铁氧体复合靶材。用XRD、EPMA和SEM分析靶材的化学成分和微观形貌。结果表明：靶材为尖晶石型铁氧体和二氧化硅的复合材料,收缩率达14.37%,能在高真空多功能磁控溅射仪正常工作,并成功制备得到性能良好的软磁薄膜。整个制备过程工艺简单,操作方便可行,大大降低了靶材的制备成本。     

二氧化硅@硫化镉核壳结构粒子的制备及表征

本文利用化学水浴沉积法,在单分散的二氧化硅球表面包覆硫化镉,制备出二氧化硅@硫化镉核壳结构.通过改变反应物质的量以及反应温度等条件,得到了具有不同核壳比的二氧化硅@硫化镉核壳结构.实验发现随着二氧化硅@硫化镉核壳结构中硫化镉晶粒尺寸的减小,其吸收边和光致发光峰都产生了蓝移;这主要是由于随着硫化镉晶粒尺寸的减小,该材料体系的光学特性由体效应向量子尺寸效应的转变造成的.     

溅射靶材的制备与应用

在信息产业不少基础产品的制造过程中,需使用多种溅射靶材,本文简介溅靶材的制造及主要应用情况。     

压电陶瓷表面硅钙复合膜的制备与表征

采用溶胶-凝胶法制备了硅钙复合溶胶，并在压电陶瓷表面制备硅钙复合膜，以改善水泥基压电陶瓷复合材料界面。确定了溶胶配比，研究了陈化、低温热处理和硅烷偶联剂对覆硅钙复合膜压电陶瓷接触角、压电和介电性能的影响。结果表明，硅钙复合溶胶中Ca与Si摩尔比>0.2时不利于成膜；提高陈化温度和延长陈化时间可明显减小硅钙复合膜的接触角；硅钙复合膜层数最佳为3层，烧结温度不大于160℃；加入微量硅烷偶联剂可有效改善膜层开裂。制备的硅钙复合膜接触角最小为27°，亲水性好。      

天然沸石陶瓷分离膜的制备与表征

以天然沸石为原料,采用挤压成型的方法,制备出多孔陶瓷分离膜管.探讨并研究了沸石的反应烧结过程,以及烧成温度、保温时间对多孔陶瓷膜管微观结构的影响,测试了不同温度烧成样品的氮气通量、水通量和弯曲强度,讨论了抗热震性和骤冷温差之间的关系,并尝试对材料的上述性能进行了解释.     

亲水性高分子-陶瓷复合膜的制备与表征

采用均质的氧化铝支撑体和不同表面层孔径的非对称氧化铝支撑体直接接枝聚丙烯酸(PAA)制备亲水性PAA-Al2O3复合膜。对所制备出复合膜的红外光谱(IR)分析、光电子能谱(XPS)分析、扫描电子显微镜(SEM)分析和表面的水接触角分析表明,成功地制备出了PAA-Al2O3复合膜。在相同实验条件下对所制备的复合膜进行纯水和纯乙醇的通量实验以及质量分数95%乙醇的脱水分离试验表明,最适合用于制备PAA-Al2O3复合膜的陶瓷膜支撑体是孔径为2～3μm的均质氧化铝支撑体,用其制备的复合膜的分离因子为139.33,通量为0.61kg/(m2.h),可以达到分离效率高、通量较大的效果.     

Preparation and characterization of CdS hollow spheres

CdS hollow spherical particles with average diameter of 800 and 850 nm have been prepared using core/shell fabrication method with poly-(styrene-acrylic acid) (PSA) latex particles as template. TEM images show that smoothly coated core/shell composite particles have been fabricated by multicycles of coating in optimum concentration of reactants. CdS hollow spheres were obtained after removing the template by dissolving the polymer in the organic solvent, and the wall thickness is about 40-100 nm.     

原位复合制备纤维素基CdS纳米复合材料及其表征

以微晶纤维素(MCC)为模板,氯化镉、硫化钠等为原料,在水的悬浮液中,用原位复合法制备了MCC/CdS纳米复合材料。对复合反应条件进行了初步研究,探讨了Cd2+浓度、Cd2+吸附时间及超声功率对复合反应的影响。研究表明,适当提高Cd2+吸附时间及超声功率有利于提高复合材料中硫化镉颗粒的复合量,Cd2+浓度对复合量的影响是显著的。应用X射线衍射(XRD),扫描电镜(SEM),红外光谱(FT-IR),光致荧光光谱(PL)对MCC/CdS复合材料进行了表征。结果表明,复合在微晶纤维素上的CdS颗粒大小均一,且均匀分布在微晶纤维素模板表面;制备的复合材料具有一定的荧光特性。     

Preparation and characterization of CdS nanocrystallites in nafion

Perfluoroethylene sulfonic acid polymer (NAFION) films are subjected to ion exchange in the medium of aqueous solutions of cadmium acetate, followed by ammonia passivation. The films are then treated with hydrogen sulfide gas for prescribed times. X-ray powder diffraction data of these samples have been analyzed for estimating the sizes of the nanocrystallites. The optical absorption spectra of the samples show an absorption edge beginning at 525 nm for the largest size clusters. A broad absorption band appears with a maximum around 410 nm–440 nm in the smaller size clusters.     

PSA@Fe3O4 doped CdS的制备及流变性能研究

用简单的湿化学方法首次制备了PSA@Fe3O4 doped CdS核壳结构复合微球.采用X射线衍射(XRD)、透射电子显微镜(TEM)、物性测试系统(PPMS)和荧光光谱(PL)对制备的样品进行表征、观察和性质测定.结果显示所制备粒子晶型稳定,尺寸均匀,分散性好.另外,所制备的样品在室温下表现出超顺磁性和荧光性质,充分显示磁性和半导体性质的良好结合.用PSA@Fe3O4 doped CdS颗粒作为磁性粒子制备磁性液体,对其在磁场下的运动和流变性能进行了研究.     

Synthesis, characterization and gas sensing property of hydroxyapatite ceramic

Hydroxyapatite (HAp) biomaterial ceramic was synthesized by three different processing routes viz. wet chemical process, microwave irradiation process, and hydrothermal technique. The synthesized ceramic powders were characterized by SEM, XRD, FTIR and XPS techniques. The dielectric measurements were carried out as a function of frequency at room temperature and the preliminary study on CO gas sensing property of hydroxyapatite was investigated. The XRD pattern of the hydroxyapatite biomaterial revealed that hydroxyapatite ceramic has hexagonal structure. The average crystallite size was found to be in the range 31–54 nm. Absorption bands corresponding to phosphate and hydroxyl functional groups, which are characteristic of hydroxyapatite, were confirmed by FTIR. The dielectric constant was found to vary in the range 9–13 at room temperature. Hydroxyapatite can be used as CO gas sensor at an optimum temperature near 125°C. X-ray photoelectron spectroscopic studies showed the Ca/P ratio of 1.63 for the HAp sample prepared by chemical process. The microwave irradiation technique yielded calcium rich HAp whereas calcium deficient HAp was obtained by hydrothermal method.     

Preparation and characterization of ceramic thin film thermocouples

Indium tin oxide (ITO), alumina doped zinc oxide (ZnO) and NiCrCoAlY/alumina nanocomposites were systematically investigated as thermoelements. These ceramic thermoelements were initially tested relative to a platinum reference electrode and the resulting thermoelectric properties were evaluated. Bi-ceramic junctions comprised of the most stable and responsive ceramic thermoelements, i.e. those thermoelements with the largest and most stable Seebeck coefficients relative to platinum, were fabricated and tested. A bi-ceramic junction based on nitrogen-doped ITO:oxygen-doped ITO exhibited excellent high temperature stability and reproducibility, however, this thermocouple pair had a relatively low Seebeck coefficient (6 μV/°C). Alumina doped ZnO:ITO thermocouples generated a very large electromotive force at low temperatures but lacked high temperature stability. When nitrogen-doped ITO was combined with a NiCoCrAlY/alumina nanocomposite, a very large and stable Seebeck coefficient (375 μV/°C) was realized. Ceramic thermocouples based on several candidate materials were demonstrated at temperatures up to 1200 °C and the potential of using these materials in other thermoelectric devices including those for energy harvesting is discussed.     

Fe3O4/CdS纳米复合微粒的合成及性能研究

用反相微乳液法合成Fe3O4/CdS纳米复合微粒.用UV-Vis、PL、VSM和TEM对产物进行了表征,并对其结合机理进行了简单分析,认为主要以化学键结合和表面类齿轮切合作用所致.还研究了不同的合成条件对复合材料性能的影响.结果表明,随着微乳液水核尺寸增大,荧光发射光谱逐渐红移,同时壳层厚度先增后减.复合材料中磁性组份比重过大会引起荧光的迅速减弱,磁性先驱物与量子点先驱物物质的量比为0.25～0.5时比较合适.     

魔芋葡甘聚糖基干凝胶的制备与性能表征

以魔芋葡甘聚糖(KGM)和淀粉等几种植物多糖为原料,通过溶胶-凝胶及冷冻干燥法制备魔芋葡甘聚糖基干凝胶。通过质构仪、扫描电镜(SEM)、比表面积分析、水蒸气吸附平衡、差示扫描热量法(DSC)和热重分析(TGA)研究了此干凝胶的结构和性能。结果表明,制备的干凝胶表面光滑平整,没有皱缩、裂纹和塌陷。干凝胶内部呈三维空间网状结构。N2吸附表明干凝胶比表面积为51.84m2/g,平均孔径为50nm。此干凝胶样品在RH50%～80%的环境中吸湿量约6%～16%,仍能保持原有的形态不变。在169℃以内具有良好的热稳定性。     

阳离子光敏抗菌型水凝胶的制备及性能表征

利用蒙脱土(MMT)分别吸附3种阳离子光敏剂(meso-四(1-甲基吡啶嗡-4-基)卟吩对甲苯磺酸盐(TMPyP)、meso-四(N-甲基-4-吡啶)卟吩四氯化锌(Zn-TMPyP)、亚甲基蓝(MB)),然后均匀分散在聚乙烯醇-苯乙烯基吡啶盐缩合物(PVA-SbQ)的水溶液中,通过紫外光交联法制备出相应的光敏MMT/PS水凝胶。借助透射电子显微镜(TEM)对MMT和MMT/PS形貌结构进行分析,利用扫描电子显微镜(SEM)、热重分析仪(TGA)对3种光敏水凝胶的内部形貌、热学性能进行分析,研究其溶胀性能及对金黄色葡萄球菌的抗菌效果。结果表明:3种光敏MMT/PS水凝胶均具有良好的溶胀性能。抗菌结果显示,三者对金黄色葡萄球菌均具有一定的杀灭效果,其中负载Zn-TMPyP的水凝胶在光照条件下对金黄色葡萄球菌的杀菌率达到98.49%。