石墨烯-铋系氧化物复合光催化材料

当前环境和能源问题越来越突出,以TiO2为代表的半导体光催化剂能够有效利用太阳能,为解决这方面问题提供了可能,其中铋系氧化物具有较高的可见光催化活性,近年来受到广泛关注。石墨烯是2004年发现的一种新型二维碳纳米材料,利用石墨烯优良的导电性能和较高的比表面积使之与铋系氧化物复合,从而提高铋系氧化物的光催化性能,是当前光催化研究领域的热点之一。相较于离子掺杂、半导体复合,它能够避免在铋系氧化物内部形成新的缺陷(光生电子空穴复合中心)。阐述了石墨烯在增强铋系氧化物光催化性能方面的最新研究进展和成果,综述了石墨烯复合对铋系氧化物的影响,即石墨烯的复合会使铋系氧化物吸光性增强,比表面积增加,光生电流增强,且光催化效率与石墨烯负载量之间存在极值关系;分析了石墨烯与铋系氧化物之间的化学键对其光催化性能的影响。最后,从石墨烯-铋系氧化物的制备、化学键合作用等方面展望了其发展趋势。     

有色金属电积用钛基氧化物涂层阳极的研究进展

综述了国内外钛基氧化物涂层阳极的研究进展及应用,包括有色金属电积用钛基贱金属氧化物涂层和贵金属氧化物涂层,其中,钛基贱金属氧化物涂层详细阐述了钛基Pb系氧化物涂层、钛基Co系氧化物涂层、钛基Mn系氧化物涂层以及钛基Sn系氧化物涂层电极;钛基贵金属氧化物涂层重点阐述了Ti/Ta_2O_5-IrO_2涂层和Ti/Ru O_2-TiO_2涂层电极。评述了多元化钛基涂层的性能、各种涂层的优势与不足。     

高镍系三元层状氧化物正极材料容量衰减机理的研究进展

高镍系三元层状氧化物正极材料因其高比容量、低廉的价格以及较好的环境友好性而受到广泛关注, 但是其固有的一些缺点, 如循环过程中结构稳定性差、高温稳定性差以及储存性能差等极大地限制了其在各领域的广泛应用。本文着重总结并讨论近年来对高镍系三元层状氧化物正极材料循环过程容量衰减机理的研究进展, 并对高镍系三元层状氧化物正极材料的进一步改性作了简要的展望。     

氧化物电子陶瓷微波烧结用保温材料MgAl2O4-LaCrO3的研究

报道了一种用于氧化物电子陶瓷微波烧结的保温体材料MgAl2O4 LaCrO3的研究和应用情况。该保温材料解决了许多氧化物电子陶瓷在微波烧结过程中易发生的热应力开裂问题并同时具有使样品均匀烧结成瓷的作用。现已成功地应用该保温体对CnMnNiO系NTC热敏材料，BaTiO3系PTC材料，ZnO掺杂系电压敏材料，LaCrO3基复合材料等氧化物电子陶瓷进行了微波烧结，烧结样品无热应力开裂并成瓷均匀致密。适用的氧化物电子陶瓷微波烧结温度区间最高可至1600℃。     

日开发代替铂催化剂的PEFC用催化剂

昭和电工参加了新能源产业技术综合开发机构（NEDO）的氧化物类非贵金属催化剂项目，并开发出了可代替现有的铂（Pt）等贵金属催化剂的PEFC（固体高分子型燃料电池）用催化剂。系分别在铌（Nb）系或钛（Ti）系氧化物中添加使用碳（C）和氮（N）。     

氧化物电子陶瓷微波烧结用保温材料MgAl2O4-LaCrO3的研究

报道了一种用于氧化物电子陶瓷微波烧结的保温体材料MgAl₂O₄-LaCrO₃的研究和应用情况.该保温材料解决了许多氧化物电子陶瓷在微波烧结过程中易发生的热应力开裂问题并同时具有使样品均匀烧结成瓷的作用.现已成功地应用该保温体对CoMnNiO系NTC热敏材料;BaTiO₃系PTC材料,ZnO掺杂系电压敏材料,LaCrO₃基复合材料等氧化物电子陶瓷进行了微波烧结,烧结样品无热应力开裂并成瓷均匀致密.适用的氧化物电子陶瓷微波烧结温度区间最高可至1600℃.     

透明氧化铝—铌封接界面显微组织的研究

利用 Al_2O_3-CaO-BaO-SrO 系氧化物玻璃焊料,将透明氧化铝与金属铌连接在一起。以透射电子显微镜结合使用扫描电子显微镜和 X 射线衍射等方法,研究了透明氧化铝—氧化物玻璃焊料—金属铌的显微组织和界面结构。并就透明氧化铝—氧化物玻璃焊料,金属铌—氧化物玻璃焊料的界面相互作用进行了讨论。     

无机天线罩功能材料的新进展

从高温天线罩功能材料的性能要求出发,回顾了无机天线罩材料的发展历程,综述了近年来氧化物系、氮化物系和磷酸盐系陶瓷基天线罩复合材料的研究进展.     

具有钙钛矿结构的SOFC用电解质材料的最新研究进展

固体氧化物燃料电池(SOFC)是20世纪80年代迅速发展起来的新型发电技术,能量转换效率可高达70%～80%,被称为21世纪最有前途的绿色能源.主要介绍了固体氧化物燃料电池所用钙钛矿结构电解质材料的研究进展,集中讨论了LaGaO3系、(Ba,Sr)CeO3系和PrGaO3系的结构特性、制备方法、电学性能和应用前景.固体氧化物燃料电池钙钛矿结构电解质材料的发展趋势是:对基质材料进行二元或多元掺杂以形成综合性能更优的复合氧化物;研究和开发与之相适宜的电极材料;进一步提高固体燃料电池的稳定性和能量转换效率.     

基于高分辨率镧系掺杂氧化物玻璃的空间三维投影

本文介绍了一种新型高效发光、高分辨率镧系掺杂氧化物玻璃的空间三维投影显示。利用镧系元素掺杂的氧化物玻璃作为空间三维投影的承载介质,测量氧化物玻璃的分辨率以及受红外光激发时的荧光光谱,并分析该材料的上转换发光机制,通过搭建实验系统,实现了三维空间悬浮显示。     

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.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

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.……     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

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 ...