电子束退火法制备ZnO薄膜

利用溶胶一凝胶法制备出ZnO的凝胶前驱膜,用电子束退火取代传统炉子退火,对前驱膜进行后处理,退火时固定电子束加速电压为10 kV,退火时间为5 min,调节聚焦束流和电子束束流,使退火温度在600～900℃范围内变化.扫描电镜(SEM)、X射线衍射(XRD)、原子力显微镜(AFM)和压电力显微镜(PFM)的测试结果表明,运用电子束退火法可制备出晶粒尺寸小于30nm、沿(002)择优取向、具有压电效应的六方ZnO薄膜,且随着退火温度的升高,晶粒尺寸逐渐变大,薄膜的结晶性和取向变好,压电效应越来越明显.     

溶胶-凝胶法制备ZnO薄膜的晶粒定向生长与光学性质

采用溶胶一凝胶法在普通化玻片上制备出高C轴择优取向的ZnO薄膜,深入研究了溶胶浓度、甩膜层数、退火温度对薄膜相结构、晶粒定向生长和紫外光吸收与可见光透射特性的影响.实验发现,在300～600℃退火范围之内,随着退火温度的升高,薄膜晶粒生长取向性增强,晶粒尺寸增大;用Zn含量为0.5mol/L的溶胶使用旋涂法甩膜和经过预热处理的5层膜再经过550℃退火1h后所形成的薄膜晶粒沿C轴高度择优取向,结构系数Tc(002)达到5.1,该薄膜的平均透射率为90%.     

溶胶-凝胶法制备ZnO薄膜及其表征

用溶胶-凝胶法在普通玻璃表面制备了ZnO薄膜,并通过XRD、SEM、UV—VIS、DSC—TGA等测试手段对ZnO薄膜进行了表征。研究表明：溶胶-凝胶法制备的ZnO薄膜透明,薄膜表面均匀分布着片状ZnO晶粒;随着退火温度的升高,ZnO晶粒在17～30nm范围内逐渐增大。     

退火处理对溶胶-凝胶法制备AZO薄膜性能的影响

采用溶胶-凝胶旋涂法在普通载玻片衬底上制备出Al3 掺杂ZnO(AZO)薄膜.对所制备的薄膜在空气气氛中进行了不同温度(400～600℃)的退火处理,并在500℃下的不同气氛(氢气和氩气)中进行退火处理.利用XRD和SEM等分析手段对薄膜进行了表征,测定了薄膜的透光性.研究表明,随空气中退火温度的提高,ZnO薄膜(002)衍射峰强度得到增强,半高宽逐渐减小,透射率从85%提高到95%.薄膜晶粒尺寸范围为23.50～29.80 nm;在氢气和氩气气氛下退火得到的薄膜性能均优于在空气中退火得到的薄膜性能.     

热处理对溶胶-凝胶法制备ZnO薄膜性能的影响

以(CH3COO)2Zn·2H2O为前驱物,利用溶胶-凝胶旋转涂膜法以普通玻璃为基底制备ZnO薄膜。分别采用X射线衍射仪、紫外-可见分光光度计和扫描电子显微镜等对ZnO薄膜的物相组分、透射率和表面形貌进行测量与表征。研究了热处理温度对ZnO薄膜的物相结构和光学特性的影响。实验结果表明,ZnO薄膜的物相结构和可见光透射率都与热处理温度有关,随着热处理温度升高,ZnO薄膜的晶粒尺寸增大,晶格常数逐渐减小,薄膜的透射率增大。     

溶胶-凝胶法制备ZnO薄膜及其光催化性能

用溶胶-凝胶法在普通玻璃表面制备了薄膜型ZnO光催化剂,通过XRD、Ab2d、UV-VIS等测试技术对ZnO薄膜进行了表征;以偶氮胭脂红为降解物,考察了薄膜退火温度、镀膜层数、溶液初始质量浓度和反应体系初始pH值对ZnO薄膜光催化性能的影响,并进行了相关机理的探讨．研究表明：溶胶-凝胶法制备的ZnO薄膜呈透明状,薄膜表面均匀分布着球形ZnO晶粒;随着退火温度的升高,ZnO晶粒在17～30mm范围内逐渐增大．光催化实验中ZnO薄膜光催化降解偶氮胭脂红的最佳工艺条件是：退火温度为300℃,镀膜层数为5层,溶液初始pH值为8～9．     

退火温度对溶胶-凝胶法制备的ZnO薄膜性质的影响

为了提高ZnO薄膜的光学性能,采用溶胶-凝胶(sol-gel)和简易浸渍提拉法在石英基片上制备ZnO薄膜,并在不同温度下进行退火处理。利用X射线衍射(XRD)、原子力显微镜(AFM)、光致发光(PL)及紫外可见分光光度计对薄膜的结构特征、表面形貌和光学性质进行表征和测试。结果表明:所制备的ZnO薄膜均为六方形纤锌矿结构,结晶程度随退火温度的升高逐渐提高,薄膜透光性能良好,当退火温度低于500℃时,ZnO薄膜在见光区的平均透过率在70%以上。     

退火温度对ZnO/Mo/ZnO透明导电薄膜结构及光电性能的影响

采用电子束蒸发法成功制备了透明导电的ZnO/Mo/ZnO(ZMZ)复合薄膜,研究了不同的退火温度对其电学和光学性质的影响规律。利用X射线衍射仪、扫描电子显微镜、X射线能谱仪、紫外可见分光光度计和四探针测试仪等检测手段对样品的性能进行了分析。实验结果表明:随着退火温度的升高,薄膜的结晶程度提高,晶粒尺寸增大;薄膜的电阻率先降低后升高;薄膜的光学透过率先升高后降低。当退火温度为250℃时,ZnO/Mo/ZnO薄膜具有最佳的综合光电性能,在400nm~900nm波长范围内最高透过率为81.4%,平均透过率高于80%,最低电阻率为1.71×10-4Ω·cm,表面电阻为15.5Ω/sq。研究表明所制备的ZMZ复合透明导电薄膜可应用于太阳能电池、液晶显示器等领域。     

退火对铝诱导结晶锗薄膜的影响及其机理

为实现在Si衬底上制备GaInP/GaInAs/Ge三结太阳电池,本工作尝试利用磁控溅射和常规退火技术,采用铝诱导结晶(AIC)法在(100)晶面单晶硅衬底上制备Ge薄膜,利用金相显微镜(Metallographic microscopy)、X射线衍射仪(XRD)、拉曼光谱仪(Raman)对其进行表征。分析了铝诱导过程中退火时间和退火温度对Ge薄膜结晶性的影响,发现退火温度越低、时间越长,制备的薄膜质量越好,确定了Ge薄膜晶化的最低退火温度为250℃,并在该温度下成功制备出了晶粒尺寸超过100nm、Ge(111)晶面择优取向度达到99%以上的Ge薄膜。     

快速热处理对BaSrTiO3薄膜微结构的影响

采用射频溅射法在Si基片上制备BaSrTiO3(BST)薄膜,利用X射线衍射和原子力显微镜(AFM)研究了快速热处理温度和时间对BaSrTiO3薄膜微结构的影响.结果表明:BST薄膜的衍射峰强度和结晶度随退火温度的升高而提高.随退火温度的升高,BST薄膜的表面粗糙度经历先降低后增大的过程,而BST薄膜的晶粒尺寸单调减小.当退火温度为700℃时,随退火时间的增加,BST薄膜的晶粒尺寸几乎不发生变化,而表面粗糙度单调减小.     

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 ...     

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     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.