退火处理对TiO2薄膜结构和透射的影响

在常温下,采用射频反应磁控溅射方法在不同溅射功率下于K9双面抛光玻璃基底上制备二氧化钛薄膜.将制备的样品进行450℃退火6h热处理.利用X射线衍射仪(XRD)对比分析了退火前后薄膜的微观结构,采用光栅光谱仪测试了退火前后薄膜样品的透射谱.实验结果表明,退火前薄膜样品是非晶态,退火后薄膜晶化为晶态,但不同溅射功率下制备的薄膜结晶取向有差异;退火热处理对薄膜的折射率有一定影响,表现为退火前后透射谱偏移.     

磁控溅射制备五氧化二钒薄膜的研究

采用射频磁控溅射的方法,在不同条件下制备了氧化钒薄膜样品,分别在不同温度条件下做了退火处理,并对退火前后样品做了X射线衍射(XRD)、X射线光电子能谱(XPS)和激光扫描共聚焦显微镜测试与分析,旨在得出制备良好的V2O5 薄膜的条件。     

退火对铪掺杂类金刚石薄膜结构和力学性能的影响

退火可以改善材料的微结构,增加其韧性和释放其内应力.采用双靶共溅技术制备了铪掺杂类金刚石薄膜(Hf-DLC)样品,并对样品进行了不同温度的退火处理,研究了薄膜退火前后的形貌、键合结构和硬度和摩擦性能等的变化.结果 表明,Hf-DLC薄膜中Hf与C形成纳米晶HfC;在250℃条件下退火,薄膜仍比较稳定;300℃退火后,薄...     

磁控溅射硅钼薄膜的抗氧化性能研究

用射频磁控溅射法在单晶Si基体上制备了硅钼薄膜,对薄膜进行真空退火处理以及高温氧化实验,借助SEM和X射线衍射仪(XRD)等仪器对退火前后的薄膜以及高温氧化后的薄膜进行了分析。结果表明沉积态的硅钼薄膜为非晶态,高温真空退火使薄膜由非晶态转变为晶态,致密的复合氧化物是硅钼薄膜具有良好的抗氧化性能的主要原因。     

制备工艺条件对HfO_2薄膜结构和性能的影响

用电子束蒸发、离子束辅助、反应磁控溅射三种方法在石英衬底上制备了氧化铪薄膜.利用掠角X射线衍射和扫描电镜分析了不同制备工艺条件下氧化铪薄膜的晶体结构和显微结构,用紫外.可见分光光度计、椭偏仪、和纳米硬度计分别测试了不同制备工艺条件下氧化铪薄膜的可见透射光谱、光学常数和硬度.结果表明薄膜的晶体结构、显微结构、光学性能和硬度等都与制备工艺有着密切的关系,电子束蒸发制备的薄膜为非晶相,而离子束辅助和反应磁控溅射制备的薄膜为多晶相,三种方法制备的氧化铪薄膜都为柱状结构,电子束蒸发和离子束辅助制备的薄膜色散严重,但反应磁控溅射制备的薄膜吸收较大,反应磁控溅射制备薄膜的硬度远大于电子束蒸发和离子束辅助制备薄膜的硬度.并分别用薄膜成核长大热力学原理和薄膜结构区域模型解释了不同工艺条件下氧化铪薄膜晶体结构和显微结构不同的原因.     

新型硅基双异质外延SOI材料Si/γ-Al2O3/Si制备

异质外延法是目前制备新型SOI材料的技术途径之一。采用低压化学气相沉积技术(LPCVD)在硅衬底上先外延γ-Al2O3绝缘单晶薄膜，制备出硅衬底上外延氧化物外延结构γ-Al2O3/Si(EOS)，然后采用类似SOS薄膜生长的常压CVD(APCVD)方法在EOS上外延硅单晶薄膜，形成新型硅基双异质SOI材料Si／γ-Al2O3／Si。利用反射高能电子衍射(RHEED)、X射线衍射(XRD)、俄歇电子能谱(AES)及MOS电学测量等技术表征分析了Si(100)／γ-Al2O3(100)／Si(100)SOI异质结构的晶体结构、组分和电学性能。测试结果表明，已成功实现了高质量的新型双异质外延SOI结构材料Si(100)／γ-Al2O3(100)／Si(100)，γ-Al2O3与Si外延薄膜均为单晶，γ-Al2O3薄膜具有良好绝缘性能，SOI结构界面清晰陡峭，该SOI材料可应用于CMOS电路的研制。     

退火温度对硅基溅射银膜微结构和应力的影响

用直流溅射法在硅(111)基底上制备银膜，膜厚为380nm。用BGS6341型电子薄膜应力分布测试仪对膜应力随退火温度的变化进行了研究，结果表明：膜应力随着退火温度的升高而增大，在400℃退火温度下膜应力变化明显。用MXP18AHF型X射线衍射仪测量了膜的衍射谱，对膜微结构随退火温度的变化进行了讨论。制备的Ag膜仍为面心立方结构，呈多晶状态，平均晶粒尺寸为23．63nm，薄膜晶格常数(0．40805nm)比标准样品晶格常数(0．40862nm)稍小。     

电泳沉积法制备GaN薄膜的结构和组分分析

采用电泳沉积法在Si(111)衬底上制备出了GaN薄膜.用X射线衍射(XRD)、傅立叶红外吸收(FTIR)谱、X射线光电子能谱(XPS)和扫描电镜(SEM)对样品的结构、组分和形貌进行了分析.结果显示所得样品为六方纤锌矿结构的GaN多晶薄膜.     

AlSb多晶薄膜的制备及性质

用磁控溅射法制备了Al/Sb多层薄膜,通过X射线衍射(XRD)、X射线荧光(XRF)、Hall效应、暗电导率温度关系及透过谱的测试研究了退火前后薄膜的结构和性质。XRD测试结果表明,刚沉积的薄膜只有Sb的结晶相,而Al则以非晶态形式存在,500℃退火后化合为AlSb多晶,且沿(111)择优取向。Hall效应测试、电导激活能及光能隙的计算结果表明,所制备的AlSb多晶薄膜为P型材料,且载流子浓度为1019cm-3,光能隙为1.64eV,电导率随温度的变化可分为两个过程,在30℃到110℃,薄膜的电导率随温度的增加而缓慢增加,而在110℃到260℃间增加明显,升温电导激活能为0.11eV和0.01eV,这与AlSb多晶薄膜在升温过程中的结构变化有关。将制备的AlSb多晶薄膜应用于TCO/CdS/AlSb/ZnTe:Cu/Au结构的太阳电池器件中,已观察到明显的光伏效应,说明用这种方法制备的AlSb多晶薄膜适于作太阳电池的吸收层。     

Zr/Nb薄膜材料的制备及界面结构研究

通过直流磁控溅射法在单晶Si(100)基底上制备了Zr/Nb/Si薄膜材料。X射线衍射(XRD)研究表明Zr薄膜以多晶形式存在,而Nb薄膜则形成了(110)晶面择优生长。薄膜中Zr和Nb晶粒大小分别为14,6 nm。扫描电镜研究表明形成的薄膜表面平整光滑,没有微裂纹存在。扫描俄歇电子能谱及X射线光电子能谱的研究表明,Zr/Nb/Si薄膜样品具有清晰的界面结构。在薄膜表面形成了致密的氧化层物种,而在膜层内部少量氧则以吸附态形式存在。     

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.     

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.     

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.