微图形Ti-O薄膜亲水性对细胞行为的影响

同时调控血小板和内皮细胞(ECs)的行为对心血管植入材料而言有着重要的意义。材料表面的亲水性和表面拓扑结构是影响细胞的粘附行为和形态的重要因素。采用光刻/湿法刻蚀及非平衡磁控溅射技术制备了微图形氧化钛薄膜,并通过紫外光照调控其亲水性,获得了亲/疏水间隔的微区,进而研究材料表面亲水性对血小板和内皮细胞粘附行为的影响。     

生物材料表面微图形化及其研究进展

生物材料表面微图形化是利用微图形技术在生物材料表面构筑具有规则、有序结构的微图形化区域，或进一步改善微图形区域表面的物理化学性质，通过研究材料表面形貌和表面物理化学性质与生物相容性的关系，获得有利于细胞生长的有序化微环境．本文综述了当前研究的材料表面微图形化加工技术、微图形在生物材料中的应用、细胞与微图形的关系等．     

内皮细胞在钛金属表面透明质酸微图形上的粘附行为

采用软刻蚀的方法在钛表面制备透明质酸(Hyaluronic acid,HA)微图形,利用高分子量的HA可以阻抗细胞粘附的性质,将内皮细胞粘附限制在一定的区域,并研究了内皮细胞的形态和细胞骨架排列情况。结果表明,HA可以通过软刻蚀的方法在钛金属表面得到轮廓清晰的的微米级小尺寸图形,该尺寸的微图形可以有效地将细胞限制在一定的区域,并能引导细胞朝一定的方向伸长,细胞骨架排列分布与细胞形态一致。这种改变细胞形态的简易方法为进一步的细胞功能及内皮化的研究提供了新的手段。     

射频溅射法制备硫化钨固体润滑薄膜的研究

本文研究了采用射频溅射法以3Cr13马氏体不锈钢为基片制备硫化钨薄膜.实验分别采用了不同的溅射功率、工作气压和沉积时间来制备样品.之后对三组样品分别进行物相分析、表面形貌观察、测定微区化学成分、结合力和摩擦系数.结果表明:通过射频溅射法可获得非晶态WS2薄膜,薄膜的S/W比一般小于2,并受溅射工艺影响较为明显,随着溅射功率的升高逐渐降低,随着溅射时间的延长明显升高.薄膜结合力受溅射工艺影响并不显著.通过射频溅射所获得薄膜的摩擦系数在一定范围内与其硫钨比成反比.     

钛表面蛋白质微图形的构建及其对人体成骨细胞粘附行为的影响

利用微接触印刷术在表面改性的钛薄膜表面构建了纤连蛋白细胞外基质微图形,激光共聚焦扫描显微镜及原子力显微镜的结果表明微图形形态规整,蛋白质层厚度约为5nm.人体成骨细胞的粘附实验表明,蛋白质微图形的尺度对细胞的粘附行为具有明显影响,通过控制微图形的尺度可以有效调控细胞的粘附与铺展行为,从而影响细胞的功能.     

Ti-O薄膜的溅射刻蚀微形貌表面对内皮细胞生长的影响

利用磁控溅射合成具有一定特性的Ti-O薄膜,并采用Ar离子溅射刻蚀该薄膜表面.运用原子力显微镜(AFM),X射线衍射(XRD)对刻蚀后的薄膜表面微观形貌、微结构进行表征.结果表明薄膜的结构未发生变化,表面的粗糙度减小.进一步的人脐静脉内皮细胞(HUVEC)种植实验表明表面粗糙度的变化对内皮细胞的贴附、生长与增殖有很大的影响.     

基于新型纳米复合介电材料的嵌入式微电容制备及特性

嵌入式微电容技术是一种能够使电子器件微型化,并提高其性能及可靠性的方法.研究适用于嵌入式环境的高介电材料,有着重要的意义.采用粒径为92 nm的钛酸钡（BaTiO3）颗粒作为纳米无机填充颗粒,选用聚酰亚胺（PI）作为有机基体制备新型BaTiO3/PI纳米复合薄膜,并对该薄膜的介电性能、耐压特性及温度特性进行了测试;并采用光刻、溅射、刻蚀等工艺,对BaTiO3/PI纳米复合薄膜进行图形化研究,制造嵌入式微电容器件原型,其后对该器件的介电性能进行了测试.测试结果显示,嵌入式电容器件原型的介电常数在低频下达到15以上,击穿场强达到58 MV/m以上,而刻蚀和溅射工艺对薄膜的性能影响不大.     

图形化表面TiO2薄膜的制备及其对内皮细胞附着形态的影响

采用光刻技术和反应离子刻蚀法(RIE)先在硅表面制备出一系列平面尺寸不同的微图形阵列,然后采用溶胶凝胶(sol-gel)浸渍提拉法在其表面制备出均匀致密、表面粗糙度一致的锐钛矿型纳米晶TiO2薄膜.利用扫描电镜(SEM)和免疫荧光标记实验研究图形尺寸对人脐静脉内皮细胞(HUVEC)附着形态的影响.实验结果发现在化学成分、细胞毒性、表面粗糙度都不对细胞附着形态产生影响的条件下,HUVEC对图形尺寸的响应为:当平面空间足够时细胞的附着伸展性能较好,而当没有足够的平面空间时细胞的附着伸展性能较差.     

Ti(Ta)O2薄膜的表面形貌对血管内皮细胞生长量影响的研究

采用磁控溅射合成不同Ta含量的系列Ti(Ta)O2薄膜.利用扫描电子显微镜(SEM)、原子力显微镜(AFM)对薄膜的表面形貌进行表征.并对薄膜表面进行人脐静脉内皮细胞(HUVEC)种植试验以评价薄膜材料的表面形貌对细胞组织相容性的影响.结果表明,细胞在不同Ta含量的Ti(Ta)O2薄膜表面因表面形貌的不同具有明显不同的粘附、增殖和生长行为.薄膜表面适当的粗糙度有利于细胞的贴附、生长和增殖.该研究指出,通过控制材料表面改性层的特征,可改善其表面细胞生物学行为,并可提高薄膜材料表面生物相容性.     

CdZnTe晶体欧姆接触电极的制备工艺研究

高阻CdZnTe晶体是X射线及γ射线探测最优秀的材料.制备CdZnTe探测器最关键的技术之一就是在CdZnTe表面制备出欧姆接触薄膜电极.关于在CdZnTe晶体表面制备接触电极用导电薄膜,大都是采用蒸发镀膜技术,膜层与CdZnTe晶体结合不很牢固.本论文主要开展了在CdZnTe晶体上欧姆接触电极的选材和制备工艺的研究.理论分析了金属与CdZnTe半导体的接触关系,根据影响因素选择Cu/Ag合金作为电极薄膜材料.利用射频磁控溅射法成功地在CdZnTe晶体上制备出Cu/Ag膜.研究发现Cu/Ag合金膜的电阻率随溅射功率的增大而增大、衬底温度的升高而降低.从理论上对这一规律进行了解释.     

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.     

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.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

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.……     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.