Micro-analysis of high-temperature oxidation-resistance of a new kind of heat-resistant grid plate in grate-kiln

To further improve the oxidation-resistance of materials and reduce the cost of grid plates in grate-kiln, a new kind of heat-resistant grid plate was developed. The microstructure of this grid plate with a life more than 18 months was studied by XRD, SEM and EDS techniques. The results show that high hardness, high intensity and good impact property make the new kind of heat-resistant grid plate and its oxide film have a higher resistance to deformation and abrasion at 900-1000°C. Besides, small grain size...     

Study on the structural characteristics of graphitized carbon microcrystal prepared from PI film using X-ray diffraction technique

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Fe3+-TiO2/SiO2气相光催化降解乙醛反应动力学研究

用浸渍法制备了Fe^3 -TiO2／SiO2负载型光催化剂,并进行了光催化降解气相中乙醛的实验和动力学研究．结果表明,Fe^3 掺杂量(nFe3 ／nTi4)为0．5％时光催化降解乙醛的效率最高;水气的存在提高了Fe^3 -TiO2／SiO2负载型催化剂的光催化活性,但使Fe^3 -TiO2纳米粉的光催化活性降低;O2的存在使Fe^3 -TiO2纳米粉和Fe^3 -TiO2／SiO2负载型催化剂的催化活性均有所降低;光强减弱使乙醛降解率下降,反应速率与光强之间呈近似线性关系;光催化降解气相中乙醛的动力学可以用Langrauir-Hinshelwood动力学方程描述．     

Preparation and characterization of nanocrystalline SnO2 thin film by electrodeposition technique

A novel process for preparing tin oxide thin films directly on copper foil by electrodeposition was developed. An optimal preparation technology to obtain SnO2 thin films was proposed with current density of 8 mA/cm2, the time of deposition of 120 min, the concentration of tin dichloride of 0.02 mol/L and the concentration of dissociated acid of 0.03 mol/L. The phase identification, microstructure and morphology of the thin films were investigated by thermogravimetric analysis and differential thermal analysis, X-ray diffraction, Fourier transform infrared spectra,scanning electron microscopy and transmission electron microscopy. The as-deposited thin film was composed of SnO2·xH2O was obtained by drying at room temperature. Nanocrystalline SnO2 thin film having tetragonal structure with average grain size in the range of 8 to 20 nm and porous, uniform surface was obtained by heat-treating the as-deposited film at 400 ℃ for 2 h. Electrochemical characterization shows that SnO2 film can deliver a discharge capacity of 798 mAh/g and the SnO2 film with smooth surface and annealed at 400 ℃ for 2 h has better cycle performance than that with rough surface and annealed at 150 ℃ for 10 h.     

Infrared thermochromic properties of VO2 thin films prepared through aqueous sol-gel process

The stoichiometric vanadium(IV) oxide thin films were obtained by controlling the temperature, time and pressure of annealing. The thermochromic phase transition and the IR thermochromic property of 400 nm and 900 nm VO2 thin films in the 7.5 μm-14 μm region were discussed. The derived VO2 thin film samples were characterized by Raman, XRD, XPS, AFM, SEM, and DSC. The resistance and infrared emissivity of VO2 thin films under different temperature were measured, and the thermal images of films were obtained using infrared imager. The results show that the VO2 thin film annealed at 550 ℃ for 10 hours through aqueous sol-gel process is pure and uniform. The 900 nm VO2 thin film exhibits better IR thermochromic property than the 400 nm VO2 thin film. The resistance of 900 nm VO2 film can change by 4 orders of magnitude and the emissivity can change by 0.6 during the phase transition, suggesting the outstanding IR thermochromic property. The derived VO2 thin film can control its infrared radiation intensity and lower its apparent temperature actively when the real temperature increases, which may be applied in the field of energy saving, thermal control and camouflage.     

室温非晶硅薄膜热电阻温度系数研究

用离子束增强沉积（IBED）方法,在SiO2/Si衬底上沉积了非晶硅薄膜和注氢的非晶硅薄膜。研究薄膜的电阻温度系数（TCR）随制备工艺的变化,分析非晶硅薄膜电阻的稳定性对电阻温度系数的影响。本征非晶硅电阻太大,虽然经过适当地退火后,TCR能够达到6.39%K-1,但是电阻值还是过高,不适合制作器件。经过硼掺杂的非晶硅薄膜,电阻显著下降,相应的TCR可以达到6.80%K-1。制作的氢化非晶硅薄膜的电阻温度系数（TCR）高达8.72%K-1,且制作工艺简单,与常规集成电路工艺兼容性好。用离子束增强沉积的非晶硅薄膜可以用于制备红外探测仪。但实验还存在着重复性不好等问题,需要作深入的实验研究。     

Cr沉积TiO_2复合薄膜的制备及其可见光催化性能

真空蒸镀法结合溶胶凝胶法成功制备Cr沉积TiO2三层复合薄膜.通过XRD、SEM、UV-vis等手段表征沉积Cr后的TiO2薄膜的结构、可见光吸收性能,以亚甲基蓝溶液为目标物评定其可见光光催化活性.结果表明:该法制备的Cr沉积TiO2复合薄膜,在723 K热处理后,蒸镀的金属层仍然为金属Cr,823 K时被氧化为Cr2O3.不同温度热处理后Cr沉积的TiO2复合薄膜在可见光区均表现出良好的光吸收性.而且随着热处理温度的升高,光吸收性能明显增强.降解实验表明,823 K热处理后的薄膜样品光催化性能最好.在可见光光照射2 h后,对亚甲基蓝溶液降解率接近40%.     

高温超导薄膜微波表面电阻测试方法的改进

介绍了一种12 GHz附近的高温超导薄膜微波表面电阻Rs测试系统。该系统采用低损耗高介电常数的蓝宝石,构成工作在TE011+δ谐振模式的介质谐振器,在77 K时,利用测量介质谐振器的Q值得到单片高温超导薄膜的微波表面电阻Rs。分析了其耦合装置对校准物理模型的影响,通过改进耦合装置可提高系统测试的准确度。该系统与前三代测试系统进行比较,其测试准确度有明显地提高。     

Corrosion Mechanism of E-glass of Chemical Resistance Glass Fiber in Acid Environment

The corrosion of ECR glass fiber was investigated by the analysis methods of weight loss ratio under different acids and at various durations.Weight loss,leaching of cations,and surface composition of ECR glass fiber were analyzed.The corrosion mechanism of ECR glass fiber in acid environment was also discussed.The experimental results showed that the corrosion degree of ECR glass fiber in different acids obeyed the order: HNO_3H_2SO_4HCl.The acid effects on corrosion of ECR glass fiberis were totally different.Hydrochloric acid mainly destroyed the network structure of [AlO_4],while sulfuric acid and nitric acid mainly destroyed the structure of [SiO_4].The acid resistance of ECR glass fiber is much better than that of E glass fiber due to the generation of intermediate product silicic acid gel Si(OH)_4 during ion exchange.It can adhere to the glass surface to form a thin film and hinder the proceeding of corrosion.     

高温超导薄膜微波表面电阻测试方法

介绍一种工作在12 GHz附近的高温超导薄膜微波表面电阻Rs测试系统,该系统采用低损耗高介电常数的蓝宝石构成工作在TE011+δ谐振模式的介质谐振器,在77 K时,利用它对高温超导薄膜的微波表面电阻Rs进行测试,提高了整个测试系统的品质因素,可成功地用于单片φ 50.8 mm较大超导薄膜的无损伤测试,整个测试系统体积小、操作方便,且所需实验条件简单,测试灵敏度高,具有简便、快捷、适合于工业化生产检测的特点。     

固载化杂多酸催化合成乙基叔丁基醚

采用溶胶-凝胶法制备出含杂多酸(HPA)的硅基催化剂,在气相反应条件下,将该催化剂用于叔丁醇和乙醇合成ETBE的醚化反应。重点考察了催化剂的组成、催化剂预处理温度、反应温度、原料摩尔比、空速等因素对醚化反应性能的影响,得到杂多酸质量分数为30%,在450℃下处理后的催化剂为最佳,最佳反应条件:温度为110℃,WHSV为2h-1,n(乙醇)/n(叔丁醇)为1.5∶1。在该条件下考察催化剂的稳定性,结果表明,在72h内活性未发生明显变化,采用烧焦法对催化剂进行再生,重复实验结果说明,采用简单的烧焦再生法,催化剂的活性得到很好的恢复。     

薄层油膜在电解质溶液中的导电机制转变

薄层油膜在电解质中的电位变化是一个电化学过程，采用组合式微电极研究了薄层油膜在5％Na2SO4溶液中导电机制转变行为。结果表明：薄层油膜在电解质溶液中存在导电机制由电子导体向离子导体转变现象，表现为薄层油膜在浸泡初期，电位随时间变化发生正移，当浸泡一段时间后，薄层油膜的电位开始随时间变化发生负移，理论分析说明：当油膜为电子导体时，所测得的电位值实际上反应了电解质溶液中的氧化剂在油膜／电解质界面发生还原反应时的平衡电位，当油膜为离子导体时，所测得的电位值实际上反应了金属在金属／油膜界面发生氧化反应时的平衡电位，因此，采用组合式微电极，通过对薄层油膜电位的精确测量，可以研究高阻薄膜（如薄层油膜）在电解质溶液中导电机制转变。     

ZnO/TiO2薄膜制备及在太阳能电池中的应用

用丝网印刷结合溶胶凝胶法制备了多孔TiO2薄膜,用溶液浸渍法制备了ZnO/TiO2复合薄膜;对薄膜的热处理制度、表面形貌、横断面结构、吸光度等进行了分析;组装电池,测试了电池的光电性能,结果表明：浸渍Zn（Ac）23 h,经过适当的热处理后,可以形成结晶良好,吸光度较好的ZnO/TiO2复合薄膜,电池的开路电压,短路电流以及光电转换效率均得到较大的提高.     

ZnO/TiO_2薄膜制备及在太阳能电池中的应用

用丝网印刷结合溶胶凝胶法制备了多孔TiO2薄膜,用溶液浸渍法制备了ZnO/TiO2复合薄膜;对薄膜的热处理制度、表面形貌、横断面结构、吸光度等进行了分析;组装电池,测试了电池的光电性能,结果表明:浸渍Zn(Ac)23 h,经过适当的热处理后,可以形成结晶良好,吸光度较好的ZnO/TiO2复合薄膜,电池的开路电压,短路电流以及光电转换效率均得到较大的提高。     

丝网印刷法制备柔性染料敏化太阳能电池碳对电极

以廉价的炭黑掺杂石墨粉,氯化聚乙酸乙烯酯为胶黏剂制成导电浆料,在柔性基底上用丝网印刷技术制备薄膜,低温热处理后即得碳对电极。通过黏度计研究了料浆的流变性能,通过四探针测试仪、扫描电镜、太阳电池测试仪,分别测试了碳对电极的方块电阻、表面形貌及其光电性能。实验表明,以叔丁醇作为分散剂,导电浆料与石墨的质量比为2∶1时,料浆的流变性能最佳,以此料浆制备的碳对电极具有较好的电性能,通过对比发现在料浆中加入石墨一定程度上提高了碳电极的性能。     

丝网印刷法制备柔性染料敏化太阳能电池碳对电极

以廉价的炭黑掺杂石墨粉,氯化聚乙酸乙烯酯为胶黏剂制成导电浆料,在柔性基底上用丝网印刷技术制备薄膜,低温热处理后即得碳对电极。通过黏度计研究了料浆的流变性能,通过四探针测试仪、扫描电镜、太阳电池测试仪,分别测试了碳对电极的方块电阻、表面形貌及其光电性能。实验表明,以叔丁醇作为分散剂,导电浆料与石墨的质量比为2∶1时,料浆的流变性能最佳,以此料浆制备的碳对电极具有较好的电性能,通过对比发现在料浆中加入石墨一定程度上提高了碳电极的性能。     

Passivation method of 317L stainless steel used in medicine

The electrochemical performance of 317L stainless steel used in medicine under different conditions of passivation(Different conternts of HNO3 solution,different passivation time and different passivation temperatures)was studied.The results show that the pitting potential of 317L stainless steel used in medicine can reach about 1.0V(SCE) when electrochemically tested in 0.9% NaCl solution after the steel was passivated in 30% HNO3 solution at 35℃for 6h,which indicates that the passivation film has a relatively strong resistance to corrosion,The results also show that the corrosion resistance of the passivation film on the surface of 317SS can be increased after suitable amount of K2Cr2O7 is added into NHO3 passivation solution.     

Effect of SiO_2 Aerogel-cement Mortar Coating on Strength of Self-Compacting Concrete after Simulated Tunnel Fire

In order to facilitate self-compacting concrete to be better used in tunnel linings that can resist fires,a SiO_2 aerogel-cement mortar coating was prepared.Based on the HC curve,a self compacting concrete cube specimens coated and uncoated with SiO_2 aerogel-cement mortar (SiO_2-ACM) were heated to simulate tunnel fire for 0.5,1,1.5,2,2.5,3 and 4 h,respectively.The residual compressive strength was tested after the specimens were cooled to room temperature by natural cooling and water cooling.The results show that,the damages of specimens become more serious as fire time goes on,but the residual strength of specimens coated with SiO_2-ACM is always higher than that of uncoated with SiO_2-ACM.In addition,the residual strength of specimens cooled by water cooling is lower than that of natural cooling.However,for the specimens coated with SiO_2-ACM,the adverse effects of water cooling are lessened.With the increase of fire time,the protective effect of SiO_2-ACM is still gradually improved.Finally,a formula was established to predict the residual 150 mm cube compressive strength of specimens protected by SiO_2-ACM after a simulated tunnel fire.     

溶胶凝胶法制备介孔五氧化二钽薄膜

以五氯化钽为反应前驱体,三嵌段两性聚合物P123做天然模板,用溶胶凝胶法制备出了介孔五氧化二钽薄膜．经过SEM检测分析,薄膜厚度约为200nm．XRD研究结果表明,制得的薄膜具有明显的介孔结构,经TEM检测可以观察到孔洞结构;得到的五氧化二钽薄膜经过400℃煅烧1h,介孔结构仍然得到保留．     

人工合成Al2OTiO5稳定性的初步研究：添加剂对AT的稳定作用

本文探讨了单独加入 MgO、SiO_2和 Cr_2O_3对 AT 的稳定作用,实验结果表明,单独引入 MgO 或 SiO_2时能改善 AT 的烧结性能和力学性能,在不明显提高热膨胀系数的情况下稳定了 AT。而 Cr_2O_3没有起到稳定 AT 的作用。利用 XRD、SEM、EPMA 等手段测试分析了物相组成、晶格常数和显微结构形貌等。