自偏压对含氢非晶碳膜光学特性的影响

利用射频等离子体增强化学气相沉积（RFPECVD）方法，以CH4、Ar和H2为气源，在CR-39树脂材料上制备出了含氢非晶碳膜（a-C：H膜）。研究了不同偏压对a-C：H膜生长过程和光学特性的影响。使用激光拉曼光谱（Raman）和傅里叶变换红外光谱（FTIR）对样品的结构和成分进行了表征，分别使用纳米压痕仪和紫外-可见光分光光度计测试了样品的机械和光学特性。结果表明，自偏压对a-C：H膜的生长具有重要影响。随着自偏压的升高，所沉积a-C：H膜中的sp^3含量降低，薄膜的硬度和光学透过率也下降。     

过渡层对含氢非晶碳膜生长的影响

本文利用射频等离子体增强化学气相沉积（RFPECVD）工艺在不锈钢基底上制备了含氢非晶碳膜（a-C：H膜）。在沉积碳膜之前，首先在基底表面预先沉积了Ti／TiC、Ti／TiN和Ti／TiN／TiC等过渡层以提高膜基结合力。利用激光Raman光谱分析了过渡层对a-C：H膜生长过程及膜中sp^3含量的影响。实验结果表明，采用Ti／TiN／TiC过渡层时所制备的a-C：H膜中sp^3含量最多，同时膜基结合力最大。     

PMMA基底含氢非晶碳膜的结构和摩擦学性能

分别用磁控溅射和等离子体增强化学气相沉积方法在PMMA基底上沉积硅膜和含氢非晶碳(a-C:H)膜.用氩离子溅射硅靶制备硅膜,以甲烷和氢气为反应气体在不同自偏压下制备非晶碳膜.分别用原子力显微镜、X射线光电子能谱和紫外拉曼光谱表征薄膜的形貌和结构,并分别用纳米压痕仪和栓盘摩擦磨损试验机测试其机械和摩擦学性能.结果表明,沉积碳膜的PMMA基底呈现出高硬度、低摩擦系数和低磨损率的特性.碳膜的显微结构、机械和摩擦学特性均显著依赖薄膜沉积过程中使用的自偏压,其摩擦系数和磨损率与其硬度和sp3含量密切相关.     

等离子体化学气相沉积类金刚石碳膜的特性及应用

类金刚石（DLC）膜是含有sp^3杂化态的亚稳态非晶碳膜，是具有极高的硬度、化学稳定性和光学透明性的半导体材料。这篇综述介绍了用等离子体化学气相沉积DLC膜的沉积方法、所制备薄膜的特性及应用，最后展望了DLC膜的发展趋势。     

CF4,CH4制备氟化非晶碳薄膜工艺研究

以CF4和CH4为源气体,用等离子体增强化学气相沉积(PECVD)方法制备了不同工艺条件下的氟化非晶碳(a-C∶F)薄膜.发现薄膜的沉积速率和射频功率几乎成正比关系,薄膜中氟的存在是导致薄膜具有紫外吸收特性的根本原因;用傅立叶变换红外光谱(FTIR)分析可知薄膜中有C-F基团的存在,使得薄膜的介电常数降低;合理控制沉积条件,可获得理想的电介质薄膜.     

电子回旋共振-微波等离子体化学气相沉积法制备a—C：H（N）薄膜

采用电子回旋共振-微波等离子体化学气相沉积技术，使用CH4和N2混合气作为反应气体，在硅衬底上制备掺氮含氢非晶碳(a—C：H(N))薄膜。紫外Raman光谱证实了薄膜的类金刚石特性；傅立叶变换红外光谱表明薄膜中存在CH和CN键结构。采用原子力显微镜(AFM)观察薄膜的微观表面形貌，结果表明薄膜表面光滑。论文详细叙述了薄膜制备工艺，对测试结果进行了分析讨论，也对这种薄膜在微电子机械系统中的潜在应用进行了探讨。     

微波功率对a—C：F薄膜结构和光学性质的影响

用苯（C6H6）和四氟甲烷（CF4）混合气体作源气体,用微波电子回旋共振等离子体化学气相沉积技术制备了含氟非晶碳膜（a-C:F)。着重讨论了输入的微波功率对成膜结构和性质的影响。我们对沉积的膜作了膜厚、扫描电子显微表面形貌（SEM）、紫外－可见光透射谱（UV-VIS)`冷静叶红外变换（FTIR）等的测量。结果表明随着微波功率的增加沉积速率一直在上升;同时膜中缺陷增多;从FTIR的结果我们发现膜中主要以C－F、CF2和F－芳基成键;通过UV－VIS吸收谱的测量的结果我们求出了折射率和光学带隙;并且将光学带隙和膜中的sp^2碳浓度建立关系。     

太阳电池用非晶碳薄膜在黑硅衬底上的生长

利用微波等离子体化学气相沉积(MPCVD)法在黑硅和抛光单晶硅片衬底上生长非晶碳薄膜,其中变量为CH4流量,分别为10sccm、14sccm、18sccm、22sccm、26sccm.通过扫描电子显微镜(SEM)、X射线衍射分析(XRD)、原子力显微镜(AFM)、拉曼光谱表征了非晶碳薄膜的结构和形貌特征.结果表明,在650℃时随着CH4流量的逐渐增加,在平整的非晶碳薄膜上C-C的sp2相团簇颗粒的直径逐渐变大.AFM测试结果显示,非晶碳薄膜表面的平均粗糙度(Ra)为0.494nm.     

非晶碳膜的表面润湿性对生物相容性的影响

采用等离子体注入沉积方法(PⅢ-D),混合通入C2H2、Ar或N2,制备了具有不同表面润湿性的非晶碳薄膜a-CH和掺N非晶碳薄膜a-CNH.采用Raman及XPS方法对薄膜的结构进行了分析,采用血小板黏附实验评价薄膜的抗凝血性能,采用材料表面的内皮细胞培养,对材料的细胞毒性以及生物相容性进行评价.结果表明非晶碳膜的生物相容性的提高与其表面的润湿性的变化密切相关,可通过掺杂特定的元素,增加a-CH薄膜表面张力的极性倾向,提高非晶碳膜的亲水性,来进一步改进a-CH薄膜的生物相容性,特别是血液相容性.     

氟化非晶碳膜的微结构分析

利用等离子体增强化学气相沉积(PECVD)法,在不同的温度下制备了氟化非晶碳膜.采用原子力显微镜(AFM)、X 射线光电子能谱(XPS)和傅里叶红外吸收光谱(FTIR)等仪器对薄膜微结构进行了表征.研究发现,氟化非晶碳膜微观结构与薄膜生长过程温度控制密切相关,温度升高,膜内键合结构变化,sp2相对含量增加.     

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.     

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.     

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.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

Effect of Oxide Assisted Metal Nanoparticles on Microstructure and Morphology of Gallium oxide Nanowires

Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from