SrWO_4纳米材料的制备及其发光性能

采用反相微乳液法和溶剂热法制备了SrWO4纳米材料,探讨了反应条件对产物的结构和形貌的影响,采用X射线衍射(XRD)、场发射扫描电镜(FESEM)和光致发光(PL)谱等手段表征了产物结构、形貌,测试了发光性能。结果表明,采用微乳液法制备SrWO4材料时,反应时间和表面活性剂浓度是影响SrWO4产物形貌的重要因素,通过改变这2个因素得到了不同形貌的SrWO4纳米材料,如菜花状、树杈状、花束状等。而溶剂热法只得到SrWO4纳米颗粒。室温PL谱表明,所制备的SrWO4材料具有较强的绿光(400～450nm)发射光谱。     

采用室温原电池电化学技术制备SrWO4多晶膜的研究

电化学技术可以分为电解型电化学技术和原电池型电化学技术两个大类.本文采用原电池型电化学路线,在含Sr2 的碱性溶液中,在室温环境下制备出了钨酸锶多晶膜,并且采用XRD、SEM、XPS和EDAX等技术对多晶膜进行了分析表征.研究发现,沉积在钨片上的材料是结晶良好的、具有单一白钨矿结构的钨酸锶多晶膜;利用原电池方法制备的SrWO4多晶膜大致呈层状或近层状生长,没有出现用恒电流电化学方法制备的SrWO4多晶膜中所出现的束状或花状枝蔓晶团簇.其原因可归因于晶体在微小电流条件下能够更加容易地呈层状生长或近层状生长.     

室温下BaWO4薄膜的电化学制备及其性能表征

为了研究电化学工艺条件对制备的BaWO-4薄膜影响,探讨BaWO-4薄膜的成膜反应机制,采用室温恒电流电化学方法直接在钨片基体上制备了白钨矿结构的BaWO-4晶态薄膜.通过XRD、SEM、XPS技术对制备的BaWO-4薄膜进行了表征.结果表明:制备的BaWO-4薄膜表面均匀致密、为四方单相结构;制备BaWO-4薄膜适宜的电化学反应工艺参数为:电流密度 1 mA/cm2,电解液的pH值为13,电化学处理时间为1 h.     

BaMoO4薄膜电化学制备适宜的工艺条件

为研究BaMoO4薄膜的电化学成膜机制,寻求适宜的制备工艺条件,采用恒电流沉积技术直接在高纯金属钼片上制备了白钨矿结构的BaMoO4薄膜.借助XRD、SEM、XPS等分析技术研究了温度和电流密度等工艺条件对制备的BaMoO4薄膜的影响.结果表明,制备的BaMoO4薄膜为四方单相结构,室温、相对较低的电流密度条件下制备的BaMoO4薄膜表面更均匀、致密.适宜的电化学制备BaMoO4薄膜的工艺条件为:室温,电流密度为0.3 mA/cm2,溶液pH值为13,反应时间为1 h.     

锂磷氧氮电解质薄膜制备与性能研究

首次采用355nm脉冲激光沉积(PLD)法在N2压强26.6Pa、激光能量密度15J/cm2、靶-基片距离5cm、基片温度为室温条件下制备了室温离子电导率为1.6×10-6S/cm、厚度均匀、无针孔、无裂缝的非晶态LiPON电解质薄膜。考察了反应气氛压强、激光能量密度对LiPON薄膜电化学性能的影响,并利用台阶仪、XPS、EDX、SEM等分析方法对薄膜进行表征。     

Sr1～xCaxMoO4固溶体薄膜的室温电化学制备及表征

为全面研究钼酸盐金属氧化物薄膜的性质,在室温碱性Ca2 、Sr2 溶液中通过电化学阳极氧化制备了Sr～xcaxMoO4多晶薄膜.采用XRD、SEM、XPS、荧光分析等测试手段,分析了薄膜的晶相结构、表面形貌、组成比及室温光致发光特性.结果表明,制备的Sr1～xCaxMoO4薄膜是四方晶相的多晶固溶体薄膜;可以通过调节溶液中Ca2 、Sr2 的组分比来控制薄膜的组分比;薄膜组分比的变化将对晶粒生长、晶格参数、薄膜表面形貌、光致发光特性等产生重要的影响.     

室温下射频磁控溅射制备ZnO:Al透明导电薄膜及其性能研究

采用射频磁控溅射技术,在室温下,以ZnO:Al2O3(2%Al2O3(质量比))为靶材,在石英玻璃基底上,采用不同工艺条件制备了ZnO:Al(AZO)薄膜。使用扫描电子显微镜观察了薄膜的表面形貌,X射线衍射分析了薄膜的结构,四探针测量仪得到薄膜的表面电阻,轮廓仪测量了薄膜厚度,并计算了电阻率,最后采用分光光度计测量了薄膜的透过率;研究了溅射功率、溅射气压与薄膜厚度对薄膜电阻率及透过率的影响。结果表明:所制备的AZO薄膜具有(002)择优取向,并且发现薄膜厚度对薄膜的光电性能有明显影响,溅射气压和溅射功率对薄膜电学性能有较大影响,但是对薄膜透过率影响不大。当功率为1kW、溅射气压0.052Pa、AZO薄膜厚度为250nm时,其电阻率为8.38×10-4Ω·cm,波长在550nm处透过率为89%,接近基底的本底透过率92%。当薄膜厚度为1125 nm时薄膜的电阻率降至最低(6.16×10-4Ω·cm)。     

基于氧化铝模板原位制备Ni/Al-LDHs薄膜的工艺及性能研究

采用电化学阳极氧化铝模板提供Al3+,在Ni(NO3)2和NH4NO3溶液中采用原位生长法制备了Ni/Al-NO3-LDHs薄膜,在弱酸性条件下通过离子交换将磺基水杨酸阴离子引入Ni/Al-NO3-LDHs薄膜层间,制备了磺基水杨酸/LDHs复合薄膜,优化了工艺条件,并借助XRD、FT-IR、SEM等手段对薄膜进行了结构和形貌分析。结果表明,磺基水杨酸阴离子成功插层于LDHs薄膜层间,层间距由0.883 nm增大为1.153 nm,NO-3离子在1 384 cm-1的特征峰基本消失,同时出现了磺基水杨酸的特征峰。SEM照片显示,LDHs晶片垂直于Al基底生长。电化学腐蚀和UV-Vis分析表明,LDHs薄膜具有良好的耐蚀性和优异的紫外阻隔性能。     

阳极氧化TiO_2纳米管阵列的制备及其光电化学特性研究

采用简单的电化学阳极氧化法在金属Ti表面制备了TiO2纳米管阵列薄膜,研究薄膜的表面形貌、晶相结构以及光吸收性质,考察其光电极的光电化学特性,结果表明,所制备的纳米管阵列膜结构高度有序,平均管径约90nm,管长约700nm。经过不同温度热处理后,薄膜结晶性质的重要性得到证实,600℃处理的光电极具有最优的光吸收和光电化学性质,最高光转化效率约1.07%。     

室温下射频磁控溅射制备ZnO∶Al透明导电薄膜及其性能研究

采用射频磁控溅射技术,在室温下,以ZnO∶Al203(2％Al2O3(质量比))为靶材,在石英玻璃基底上,采用不同工艺条件制备了ZnO∶Al(AzO)薄膜.使用扫描电子显微镜观察了薄膜的表面形貌,X射线衍射分析了薄膜的结构,四探针测量仪得到薄膜的表面电阻,轮廓仪测量了薄膜厚度,并计算了电阻率,最后采用分光光度计测量了薄膜的透过率;研究了溅射功率、溅射气压与薄膜厚度对薄膜电阻率及透过率的影响.结果表明:所制备的AZO薄膜具有(002)择优取向,并且发现薄膜厚度对薄膜的光电性能有明显影响,溅射气压和溅射功率对薄膜电学性能有较大影响,但是对薄膜透过率影响不大.当功率为1kW、溅射气压0.052 Pa、AZO薄膜厚度为250nm时,其电阻率为8.38×10-4Ω·cm,波长在550 nm处透过率为89％,接近基底的本底透过率92％.当薄膜厚度为1125 nm时薄膜的电阻率降至最低(6.16×10-4 Ω·cm).     

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.     

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.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to