In vitro biocompatibility of titanium-nickel alloy with titanium oxide film by H2O2 oxidation

Titanium oxide film with a graded interface to NiTi matrix was synthesized in situ on NiTi shape memory alloy（SMA） by oxidation in H2O2 solution. In vitro studies including contact angle measurement, hemolysis, MTT cytotoxicity and cell morphology tests were employed to investigate the biocompatibility of the H2O2-oxidized NiTi SMAs with this titanium oxide film. The results reveal that wettability, blood compatibility and fibroblasts compatibility of NiTi SMA are improved by the coating of titanium oxide film through H2O2 oxidation treatment.     

不同晶粒形状材料的力学性能

采用有限元的方法来模拟纳米压痕实验的加、卸载过程,采用的是简化了的二维模型,有限元模型考虑了纳米压痕的标准Berkovich压头,介绍了有限元模型的几何参数、边界条件、材料特性与加载方式。从所得到的载荷与压入深度的关系曲线,以及由此计算而得到的硬度-位移曲线等为依据,对在纳米压痕测试过程中,不同的晶粒截面形状以及截面面积对整体材料的力学性能的影响进行了分析讨论。研究表明,在晶粒截面面积相等的情况下,当纳米压痕实验压入相同的深度时,晶粒的截面形状为矩形的材料的硬度高于晶粒的截面形状为三角形的材料的硬度,而且,当晶粒的截面形状相同的情况下,整体材料的硬度与晶粒截面的面积存在一种近似的正比例关系。这种研究结果说明,即使在材料相同的情况下,如果晶粒的截面形状不同,由于力学传递关系的不同,仍然能够使得薄膜具有不同的宏观力学性能。     

金属等离子体浸没离子注入改善9Cr18轴承钢表面耐磨性的研究

采用新改进的阴极弧金属等离子体源,对９Ｃｒ１８轴承钢进行了金属等离子体浸没离子注入（ＰⅢ）处理,首先将Ｔｉ、Ｍｏ和Ｗ离子分别注入到９Ｃｒ１８钢的表面,然后再对其进行Ｎ等离子体浸没离子注入,从而在９Ｃｒ１８钢表面形成了一层超硬耐磨的改性层。     

磁控溅射技术及其发展

磁控溅射技术可制备超硬膜、耐腐蚀摩擦薄膜、超导薄膜、磁性薄膜、光学薄膜,以及各种具有特殊功能的薄膜,在工业薄膜制备领域的应用非常广泛.本文着重介绍了磁控溅射技术原理、特点、磁控溅射技术的发展史及其发展趋势.     

ZnO/p-Si异质结构的电学输运特性

采用等离子体浸没离子注入沉积方法,在p型Si衬底上制备了具有整流特性的、非故意掺杂的以及掺氮的ZnO/p-Si异质结.非故意掺杂的ZnO薄膜为n型(电子浓度为1019cm-3数量级),掺氮的ZnO薄膜为高阻(电阻率为105Ω·cm数量级).非故意掺杂的ZnO/p-Si异质结在正向偏压下,当偏压大于0.4V,电流遵循欧姆定律.然而对于掺氮的ZnO/p-Si样品,当偏压小于1.0V时,电流表现为欧姆特性,当偏压大于2.5V时,电流密度与电压的平方成正比的关系.分别用Anderson模型和空间电荷限制电流模型对非故意掺杂和掺氮的ZnO/p-Si异质结二极管的电流输运特性进行了解释.     

多靶磁控溅射系统磁场优化设计

磁场分布对磁控溅射稳定性、离化率、靶材利用率及成膜质量都有重要影响,合理分布可使靶材附近等离子体分布均匀,不同位置溅射速率差减小,靶材刻蚀范围增大,靶材寿命延长,溅射过程稳定性提高。本文针对六靶复合表面改性设备,用有限元法对磁场进行模拟,得到较理想的磁场分布,为优化设计提供理论依据。     

SiOx调制的三元硅化物(C01-xNix)Si2外延

报道了通过Co/Ni/SiOx/Si(100)体系固相反应,实现三元硅化物(Co1xNix)Si2薄膜外延生长及薄膜特性的表征.测试结果表明,中间氧化硅层对原子扩散起到阻挡作用.XRD和RBS图谱显示,有中间层的样品所形成的硅化物膜和硅衬底有良好的外延关系.而Co/Ni/Si(100)体系,则形成多晶硅化物膜,和硅衬底没有外延关系.外延三元硅化物(Co1-xNix)Si2膜的晶格常数介于CoSi2和NiSi2之间,从而可以降低生成膜的应力.薄膜的厚度约为110nm;最小沟道产额(Xmin)为22%.外延三元硅化物膜的电阻率约为17μΩ@cm;高温稳定性达1000C,与CoSi2膜相当.     

超高真空电子束蒸发在多孔硅上外延单晶硅

采用超高越空电子束蒸发的方法在用阳极氧化制备的多孔硅衬底上外延单晶硅,研究了不同多孔硅衬底对外延质量的影响。采用高能电子衍射表征外延层的晶体结构,截面透射电镜上材料的微结构,原子力镜表征外延层表面的粗糙度,卢瑟福背散射／沟道表征外延层晶体质量,扩展电阻表征材料的电学性能。一系列的测试结果表明对在5mA／cm^2电流密度下阳极氧化10min形成的多孔硅衬底,可用超高真空电子束蒸发的方法外延出质量良好的单晶硅。     

Novel method of separating macroporous arrays from p-type silicon substrate

This paper presents a novel method to fabricate separated macroporous silicon using a single step of photo-assisted electrochemical etching. The method is applied to fabricate silicon microchannel plates in 100 mm p-type silicon wafers, which can be used as electron multipliers and three-dimensional Li-ion microbatteries. Increasing the backside illumination intensity and decreasing the bias simultaneously can generate additional holes during the electrochemical etching which will create lateral etching at the pore tips. In this way the silicon microchannel can be separated from the substrate when the desired depth is reached, then it can be cut into the desired shape by using a laser cutting machine. Also, the mechanism of lateral etching is proposed.     

Control of multidrug-resistant planktonic Acinetobacter baumannii: biocidal efficacy study by atmospheric-pressure air plasma

In this research,an atmospheric-pressure air plasma is used to inactivate the multidrug-resistant Acinetobacter baumannii in liquid.The efficacy of the air plasma on bacterial deactivation and the cytobiological variations after the plasma treatment are investigated.According to colony forming units,nearly all the bacteria (6-log) are inactivated after 10 min of air plasma treatment.However,7％ of the bacteria enter a viable but non-culturable state detected by the resazurin based assay during the same period of plasma exposure.Meanwhile,86％ of the bacteria lose their membrane integrity in the light of SYTO 9/PI staining assay.The morphological changes in the cells are examined by scanning electron microscopy and bacteria with morphological changes are rare after plasma exposure in the liquid.The concentrations of the long-living RS,such as H2O2,NO3,and O3,in liquid induced by plasma treatment are measured,and they increase with plasma treatment time.The changes of the intracellular ROS may be related to cell death,which may be attributed to oxidative stress and other damage effects induced by RS plasma generated in liquid.The rapid and effective bacteria inactivation may stem from the RS in the liquid generated by plasma and air plasmas may become a valuable therapy in the treatment of infected wounds.