掺氮TiO_(2-x)N_x薄膜托槽的制备及其性能研究

利用射频磁控溅射制备了氮掺杂TiO2-xNx薄膜托槽,通过X射线衍射(XRD)、扫描电镜(SEM)等测试手段表征了托槽表面薄膜的结构、形貌,并通过原子力显微镜(AFM)、多功能材料表面试验仪等研究了TiO2-xNx薄膜与基底托槽的附着力、TiO2-xNx薄膜托槽的表面粗糙度以及表面摩擦系数。结果表明制备的托槽表面为均一的锐钛矿相结构TiO2-xNx薄膜,晶粒粒径为30nm,纳米TiO2-xNx薄膜托槽表面致密、平整,薄膜与托槽衬底结合紧密、附着性好,托槽表面粗糙度降低,摩擦系数变小,改善了托槽表面性能,为抗菌性研究奠定了基础。     

金属托槽表面TiO2-xNx薄膜的生物摩擦磨损性能研究

考察金属托槽表面掺氮TiO2-xNx薄膜的生物摩擦磨损性能。采用射频磁控溅射法在不锈钢金属托槽原材料表面制备掺氮TiO2-xNx薄膜,通过扫描电子显微镜(SEM)和X射线衍射(XRD)技术分析薄膜微观结构,利用UMT-2MT型摩擦磨损试验机考察薄膜的体外生物摩擦磨损性能。结果表明所制备的掺氮TiO2-xNx薄膜为锐钛矿结构,纳米量级,薄膜均匀致密;在干摩擦及人工唾液和Hank’s溶液的润滑条件下,掺氮TiO2-xNx薄膜均表现出良好的抗磨损低摩擦性能。     

掺氮TiO_(2-x)N_x薄膜托槽的细胞相容性研究

采用射频磁控溅射法在普通MBT直丝弓金属托槽表面制备了锐钛矿相掺氮TiO2-xNx薄膜,通过MTT比色法、细胞形态学观察、扫描电镜及荧光染色法评价薄膜托槽的细胞学性能。结果表明,掺氮TiO2-xNx薄膜托槽的细胞毒性为0级,与对照组相比,薄膜托槽组细胞的相对增殖率差异无统计学意义(P0.05);扫描电镜图像显示细胞在薄膜托槽表面贴壁生长良好;荧光显微镜观察显示粘附在材料表面的细胞其细胞核呈亮黄绿色荧光,细胞质呈绿色荧光,细胞生长良好。由此证明掺氮TiO2-xNx薄膜托槽具有良好的细胞相容性。     

ITO/TiO2-xNx/NiO复合电极制备及其光电化学性能

以三乙胺为氮源,钛酸丁酯为钛源,采用溶胶-凝胶法制备氮掺杂TiO2,并用旋涂法制备ITO导电玻璃为基材的氮掺杂TiO2薄膜,经300℃、400℃、500℃处理制得ITO/TiO2-xNx薄膜。采用XRD、XPS、SEM和UV-Vis吸收光谱等对样品进行表征,并进行光电化学性能测定,结果表明500℃处理制得的ITO/TiO2-xNx薄膜具有最佳的光电催化性能。进一步采用化学沉积法在ITO/TiO2-xNx薄膜表面上沉积多孔NiO薄膜,制得ITO/TiO2-xNx/NiO复合薄膜,研究表明该复合薄膜具有很好的光电致色特性及储放电性能,可应用于光电致变色和光电能量储存领域。     

氩气流量对四面体非晶碳膜结构和摩擦性能的影响

利用自主研制的45°单弯曲阴极电弧沉积系统,通过改变Ar流量(2,5以及10 ml/min),在p型(100)硅基底上制备了四面体非晶碳膜。借助表面轮廓仪测定薄膜厚度和粗糙度变化;采用X射线光电子谱获得薄膜微结构信息,利用残余应力仪和摩擦磨损试验机测定薄膜的内应力和摩擦学性能。实验结果表明:随Ar流量增加,薄膜的沉积速率降低,表面趋于光滑;薄膜中sp3含量由2 ml/min时的68%下降至10 ml/min时的55%;薄膜应力值随Ar流量的增大而减小,在10 ml/min处取得最小值;不同Ar流量条件下所制备薄膜的摩擦系数在0.024~0.045之间,且随Ar流量增加而增大。     

柱状晶形貌TiO2膜厚对FTO/TiO2镀膜玻璃光催化活性影响

采用溶胶凝胶法,在FTO(SnO2:F)低辐射镀膜玻璃衬底上制备了柱状晶体结构的TiO2薄膜,获得双层结构FTO/TiO2镀膜玻璃样品.研究了TiO2薄膜厚度对FTO/TiO2镀膜玻璃样品的光催化活性、低辐射性能以及透光性能的影响.结果表明,FTO/TiO2镀膜玻璃样品光催化活性随着TiO2薄膜厚度的增加先升高后下降,在TiO2薄膜厚度为300 nm时光催化活性最佳;低辐射性能随着TiO2薄膜厚度的增加而下降,但TiO2薄膜厚度为300 nm时仍然具备一定的低辐射性能;透光性能与TiO2薄膜膜厚的关系不大,可见光透射比保持在72%左右;表面平均粗糙度约为1 nm,表面光滑,不易沾染油污灰尘.该镀膜玻璃在保证低辐射建筑节能和透光的前提下,兼具光催化自清洁功能,具有很好的应用前景.     

多层纳米TiO2薄膜的摩擦学性能研究

采用溶胶-凝胶法在普通载玻片上制备了1-4层纳米TiO2薄膜,使用AFM、SEM及UMT-2MT摩擦试验机等考察了薄膜的表面形貌、磨痕形貌及不同条件下的摩擦学性能.实验结果表明,所制备的薄膜平整、致密并具有良好的减摩抗磨性能.与TiO2/GCr15钢球相比TiO2/Si3N4陶瓷球摩擦副的摩擦学性能更稳定;薄膜的耐磨性能并不随膜层数的增加而增大,2层薄膜具有最佳的摩擦学性能;薄膜的摩擦失效机理主要为严重塑性变形、磨粒磨损和局部脆性断裂.     

纳米TiO2薄膜表面形貌与光致双亲性能的研究

采用溶胶-凝胶法,利用旋涂技术在玻璃表面制备了纳米TiO2薄膜.用X射线衍射仪(XRD)分析薄膜组成结构;用原子力显微镜(AFM)对薄膜表面形貌、粗糙度进行表征;以去离子水和苯作为水和油模型,研究了TiO2薄膜光致双亲的机理和表面薄膜粗糙度与双亲性的关系.结果表明:在550℃时,晶体生长得较完整,薄膜中的TiO2以锐钛矿形式存在,TiO2粒子的平均直径为26.2nm;双亲性跟表面粗糙度有关,粗糙度越大薄膜的双亲性能越好.     

纳米TiO2薄膜的低温制备

采用液相沉积法,在90℃下制备了纳米锐钛矿型TiO2薄膜.采用XRD、UV透射光谱、薄膜表面接触角的测量、厚度的测量及亚甲基蓝降解等手段研究了TiO2薄膜的性能.结果表明所制备的TiO2薄膜具有较好的超亲水特性及光催化活性,在可见光范围内具有较好的透明性,其平均透光率在80%以上.     

环境气氛对类金刚石薄膜摩擦学行为的影响

用射频等离子体化学气相沉积法(RF-PECVD)制备了含氢类金刚石薄膜(DLC).采用表面轮廓仪和纳米压痕仪分别测量膜的厚度和硬度.通过控制摩擦环境气氛对DLC薄膜和钢球对磨的摩擦系数进行了系统研究.利用光学显微镜和扫描电镜(SEM)分析了磨痕及磨斑的形貌,对DLC薄膜在不同气氛下的摩擦现象进行了表征和解释.结果表明,DLC薄膜的摩擦学行为与气氛中的O2、H2O和N2有关,其中N2的存在是DLC薄膜具有超低摩擦系数的重要原因.     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.