光催化抗菌薄膜的制备与性能研究

采用溶胶-凝胶法,结合旋转涂膜法,制备了六种稀土掺杂光催化抗菌薄膜(Ce/TiO2,Pr/TiO2,Gd/TiO2,Dy/TiO2,Y/TiO2,Eu/TiO2),研究了影响薄膜光催化抗菌性能的因素,确定了最佳制备工艺条件.、除Ce掺杂TiO2薄膜含有极少量金红石型TiO2外,其余全部由单一锐钛矿型TiO2构成,薄膜表面均存在缺陷.RE/TiO2光催化抗菌薄膜对大肠杆菌平均杀菌率皆在90%以上,与纯TiO2的杀菌率34%相比有明显提高.稀土元素掺杂显著提高了光催化薄膜对可见光的响应.经反复使用和高温、高压、冲刷等处理,薄膜完整不脱落,始终有很高的杀菌率和稳定性.稀土掺杂TiO2具有良好的实用价值和应用前景.     

TiO2薄膜电极光电转换性能的影响因素

采用溶胶-凝胶法在玻璃基体表面制备了不同粒径的TiO2薄膜和纳米SnO2/TiO2复合薄膜,将它们与不同对电极进行了光电转换性能测试.结果表明:氧化物薄膜电极经染料敏化、薄膜颗粒细化及薄膜复合化都有利于提高电极的光电转换性能.用汞溴红敏化后,粒径为25 nm的TiO2薄膜的光电转换性能提高了847倍;粒径为25 nm的TiO2薄膜的光电转换性能是粒径为136 nm的TiO2薄膜的5倍;粒径为25 nm的TiO2薄膜经粒径为27 nm的SnO2薄膜复合后,其光电转换性能提高了7.7%.     

阳极氧化工艺及改性对TiO2纳米管阵列薄膜疏水性的影响

采用阳极氧化法在钛片表面制备TiO 2纳米管阵列薄膜,研究了不同氧化电压(15～25 V)和时间(0.5～2 h)下薄膜的微观结构;采用硬脂酸对其进行改性,分析了薄膜改性前后的润湿性能.结果表明:TiO 2纳米管平均管径和管间距随氧化电压增大而增大,随氧化时间的变化不明显,而表面结构均匀性则受氧化时间影响,氧化2 h的...     

硅PN结基底TiO2氧传感器的特性研究

采用薄膜工艺及MEMS工艺研制了一种以硅PN结为基底材料的TiO2氧传感器,阐述了该传感器的工作原理、工艺流程及射频磁控溅射制备银电极及TiO2薄膜的方法.利用XRD、SEM分析了薄膜的表面形貌及晶粒结构.基于该结构的氧传感器具有良好的感特性及响应特性,具有响应时间短、信号线性度好、灵敏度高等优点.     

Ag掺杂对TiO2纳米薄膜结构及摩擦学性能的影响

采用溶胶凝胶法在普通载玻片上制备了TiO2和Ag/TiO2纳米结构薄膜,利用X射线衍射仪(XRD)、X光电子能谱(XPS)、原子力显微镜(AFM)及UMT-2摩擦试验机,考察了Ag掺杂量对薄膜组成结构、表面形貌及摩擦学性能的影响。实验结果表明,Ag掺杂量对TiO2薄膜表面形貌和减摩抗磨性能产生重要影响,低掺杂时Ag自润滑性能对薄膜摩擦性能的增强作用占主导,而高掺杂时其对薄膜的影响主要表现为恶化表面,从而导致摩擦性能下降。本研究测试条件下,掺杂量为5.0%(摩尔分数)时具有最佳的耐磨寿命和最低的摩擦因数。     

烧结制度对稀土掺杂TiO2光催化抗菌材料抗菌性能的影响

采用溶胶-凝胶法并结合旋转涂膜法制备了稀土掺杂（Ce、Pr、Gd、Dy、Y、Eu）薄膜型光催化抗菌材料，利用TG—DSC综合热分析仪研究了烧结方式、烧结温度以及烧结时间等烧结制度对稀土掺杂TiO2光催化抗菌材料抗菌性能的影响。结果表明，各因素对材料的光催化抗菌性能均存在一最佳值，稀土元素掺杂对TiO2的晶型结构产生了一定的影响；薄膜中除Ce掺杂TiO2薄膜含有极少量金红石型TiO2外，其余全部由单一锐钛矿型TiO2构成，相比稀土掺杂TiO2薄膜对大肠杆菌的杀菌率可达93．38％，较纯TiO2（杀菌率为37．14％）杀菌效果提高了60．23％。该材料经反复使用仍具有很高的杀菌率和稳定性，极具实用价值和应用前景。     

阳极氧化法制备TiO_2薄膜的力学性能与摩擦磨损性能

在不同的电解液体系中,利用阳极氧化法在TC4钛合金基体上制备了不同形貌的TiO2薄膜,分析了电解液体系及电压对薄膜形貌的影响;测试了薄膜的显微硬度、弹性模量和摩擦磨损性能。结果表明:TiO2薄膜的形貌与电压、电解液密切相关,电压过小或过大时薄膜形貌呈非纳米管结构,在HF溶液及含F-的无机电解液中,电压在10~20V时,薄膜形貌呈有序的纳米管状;在含F-的有机电解液中,当电压为40V时,薄膜呈纳米弹簧结构;非纳米管结构薄膜的显微硬度大,弹性模量高,耐磨性不佳;纳米管的管径与壁厚的比值越小,薄膜的力学性能和耐磨性越好;纳米弹簧状薄膜的显微硬度和弹性模量皆较小,摩擦因数高,磨损量大。     

金属丝网负载纳米二氧化钛薄膜的制备及催化实验

采用溶胶-凝胶工艺在金属丝网表面制备了均匀透明的锐钛矿型TiO2纳米薄膜，通过XRD，TEM对薄膜进行了表征，其颗粒大小在12-20nm，薄膜成膜形态良好。利用甲醛催化实验评价了TiO2纳米薄膜的光催化性能。通过甲醛降解试验，证明了该薄膜具有良好的催化性能。     

层状结构金属化合物薄膜的制备及表征

采用分析纯TiO2、Nb2O5和K2CO3粉末为原料，采用高温固相反应制备出具有层状结构的K4Nb6O17和K2Ti4O9粉末，经过湿磨和离心沉淀分离，用旋转涂敷法在石英玻璃基片表面制备K4Nb6O17和K2Ti4O9薄膜。对所制备K4Nb6O17薄膜进行H^ 离子交换和正丙胺层间插入反应，用XRD对所制备的粉末和薄膜进行了表征。结果表明：所制得的薄膜均具有层状结构，因此有希望用此方法制备半导体复合金属化合物光催化薄膜。     

等离子浸没离子注入合成TiN/Ti-O梯度薄膜的成分与力学性能

用等离子浸没离子注入和沉积(PⅢ-D)的方法,采用三种工艺分别在Si、Ti6Al4V和热解碳(LTIC)表面合成了TiN／Ti-O梯度薄膜。用可编程逻辑控制器(PLC)为核心的一套控制系统控制金属源阴极的推进和气体成分的改变。使用纳米压痕仪、针盘式摩擦磨损试验机和结合力测试仪分析了梯度薄膜的力学性能,梯度薄膜硬度最高可达19.5 GPa,薄膜结合力可达到68 N左右。采用X射线衍射(XRD)分析表明,表层的薄膜为具有金红石结构的氧化钛,二次离子质谱(SIMS)对薄膜进行了定性分析,证实薄膜具有梯度特性。采用X射线光电子能谱(XPS)对梯度薄膜进行近表面成分分析,结果表明合成的TiN／Ti-O薄膜是非化学计量的,其成分组成为TiO2、Ti2O3和TiO。使用扫描电镜(SEM)观察了薄膜磨痕、结合力划痕,结果表明,控制合成的TiN／Ti-O梯度薄膜具有良好的力学性能。     

超薄含水油膜Couette流润滑特性的分子动力学模拟

基于分子动力学方法,建立超薄含水柴油膜的全原子分子模型,进行不同含水率下油膜Couette流的润滑特性研究。在相同剪切速度作用下,分析含水油膜的微观结构、速度分布、整体键取向参数、剪切黏度等性质。发现不含水时油膜形成了类固体层,不具有流动性,且在剪切过程中黏度值下降,即表现出剪切时间稀化现象;而含水工况下,油膜出现分层结构,流速符合Couette流的流动特性;且含水率越高,油膜的分层现象越明显,链烃的有序性越强,致使油水混合薄膜的剪切黏度值也越低,呈现出非牛顿流体性质,此时油膜固有的剪切稀化特性被削弱。研究表明,水分子由于具有较强的分子间作用力,能促使油膜中的有机分子重新排布,从而对油膜的润滑性能产生较大改变。     

A biomimetic approach for effective reduction in micro-scale friction by direct replication of topography of natural water-repellent surfaces

In this paper, we report on the replication of surface topographies of natural leaves of water-repellent plants of Lotus and Colocasia onto thin polymeric films using a capillarity-directed soft lithographic technique. The replication was carried out on poly(methyl methacrylate) (PMMA) film spin coated on silicon wafer using poly(dimethyl siloxane) (PDMS) molds. The friction properties of the replicated surfaces were investigated at micro-scale in comparison with those of PMMA thin film and silicon wafer. The replicated surfaces exhibited superior friction property when compared to those of PMMA thin film and silicon wafer. The superior friction behaviour of the replicated surfaces was attributed to the reduced real area of contact projected by them.     

光学薄膜技术在光通信技术中的应用

介绍了光纤通信系统中用薄膜技术制成的光定向耦合器 ,波分复用器等原理及制作方法。叙述了用薄膜滤光片技术改善 EDFA的传输特性。     

Prevention of fretting by ion plated film

A new technological application of the ion plating technique to the prevention of fretting has been studied. Ion plating was done using gold and silver, which are commonly employed as thin metal film lubricants and also boron carbide which has extremely good wear resistance. The anti-fretting property of the ion plated film was always superior to that of the sputtered or vacuum evaporated film. The ion plated boron carbide film showed the best resistance to fretting. The better adhesion of ion plated films was responsible for the better anti-wear property. Transmission electron microscopy was used to study ion plated films.     

Characterization and tribological investigation of self-assembled lanthanum-based thin films on glass substrates

Rare-earth (RE) (lanthanum-based) thin films were prepared on hydroxylated glass substrates by a self-assembling process from specially formulated solution. Atomic force microscope (AFM) and X-ray photoelectron spectrometry (XPS) and scanning electron microscope (SEM) are used to characterize the thin films. The tribological properties of the as-prepared thin films sliding against a steel ball were evaluated on a friction and wear tester. The tribological experiment shows that the friction coefficient of glass substrate reduced from 0.85 to 0.13 after the formation of RE self-assembled film (SAM) on its surface. And the RE self-assembled film has longer wear life (2880 sliding pass). It is demonstrated that RE self-assembled film exhibited good wear resistant property. The superior friction reduction and wear life of RE films are attributed to good adhesion of the film to the substrate and special characteristic of the RE elements.     

Development of RF magnetron sputtering method to fabricate PZT thin film actuator

PZT piezoelectric very thin films suitable for a microactuator have been deposited onto Invar alloy substrate using a high-temperature RF magnetron sputtering technique. PZT thin films must be deposited onto conductive substrate for a monomorph or a bimorph actuator. The chemical composition and the crystalline structure of these films were measured by ESCA and XRD, respectively. The chemical composition of PZT deposited stoichiometrically was almost the same as commercially-produced bulk PZT. Crystal planes (1 1 0) and (1 1 1) of PZT perovskite structure were observed in XRD analysis. When the substrate was heated to above 600 °C, SEM revealed only a very small number of pinholes on the surface. A thin (500 nm) film actuator has been characterized by measuring the piezoelectric property using a Laser Doppler Vibrograph. It was confirmed that the piezoelectric property has a linear relationship with the grain size, which also increased with the substrate temperature. The piezoelectric property of deposited PZT thin films showed a good agreement with a quoted value of bulk PZT, when the substrates were heated to 600 °C.     

水介质液压泵锥形轴配流副轴承间隙的计算

以水介质轴向柱塞液压泵的锥形轴配流副为研究对象,对其在稳定工作状态下形成的滑动轴承的径向间隙计算方法进行了研究。采用等效结构参数法将配流副滑动轴承化为轴向推力轴承,根据柱塞轴向液压交变作用力引起轴承内水膜的变化特征推导出水膜厚度变化的速度,再依据锥顶体薄膜挤压效应公式计算出了轴承的径向间隙,结果表明径向间隙是柱塞泵工作压力和配流副结构参数的函数。     

流体吸附层厚度及位能界面的划分

根据流体吸附性能及流体粒子在固体表面的分布规律，应用能量的观点可以得出流体位能的分布规律，由此可知液体的性能，在薄膜润滑条件下表面作用尤其重要。应用能量的观点把液体的分布密度忽略，将使公式计算简化。     

薄膜润滑与润滑状态图

讨论了速度、固体表面能、滑动比、润滑剂粘度和化学性能对薄膜润滑状态下油膜厚度的影响,以及弹流润滑向薄膜润滑转化条件和液体膜失效条件。进而提出了新的润滑状态划分准则以及不同润滑机理下膜厚的变化情况。     

固体,液体及气体材料折射率的实验测定和误差分析

本文根据固体、液体、气体及介质薄膜物理性质上的差异，分别给出了它们折射率的测量原理、方法及测量精度，并分析了误差产生的原因。