乙酸异戊酯共沸干燥法制备低团聚掺锑氧化锡纳米微粉

以SnCl4·5H2O和SbCl3乙醇溶液为原料,用阴离子树脂交换除氯水解法制备得到无氯离子的前驱体掺锑氢氧化锡胶体沉淀。首次对以含氧官能团为主的系列憎水有机溶剂进行了共沸干燥脱水研究,并对所得粉体团聚程度进行比较。实验发现掺锑氧化锡共沸脱水干燥效果与有机溶剂分子结构之间有密切关系,提出了选择共沸有机溶剂的3个原则,在一系列有机溶剂中选择了最符合的乙酸异戊酯进行干燥实验,与常用的正丁醇共沸溶剂进行了消除粉体团聚效果的比较。运用IR、BET、TEM、XRD等方法对掺锑氢氧化锡粉体的结构、比表面积、形貌、物相进行表征。结果表明,乙酸异戊酯溶剂是理想的共沸干燥有机溶剂,其干燥所得掺锑氢氧化锡蓬松粉体的比表面积为284.44m2/g,比用正丁醇处理的增大了22%。将乙酸异戊酯干燥所得的掺锑氢氧化锡微粉经热处理后得到了低团聚的掺锑氧化锡纳米微粉。     

掺锑的纳米SnO2/WPU复合隔热涂层的制备与表征（英文）

利用掺锑的纳米SnO2和水性聚氨酯(WPU)制备了透明隔热的复合涂层.实验发现涂层的隔热起因于涂层中掺锑的纳米SnO2粒子对红外线的吸收.隔热测试结果表明在阳光的照射下,涂层表面的温度升高,而测试箱内的温度最大下降17.5℃.实验制备的掺锑的纳米SnO2/WPU复合隔热涂层具有许多优点,如成本低、化学性能稳定、制作方便等,是一种性价比较高的隔热涂层.     

非均相沉淀制备Cu包裹纳米SiC复合粉体颗粒

选用工业生产的立方相SiC纳米颗粒,尺寸约120nm,利用置换反应原理制得纳米Cu微晶。采用非均相沉淀方法将Cu包裹到纳米SiC颗粒表面,形成相分布均匀的复合颗粒,纳米Cu微晶吸附在SiC颗粒周围形成粗糙表面,复合粉体颗粒表面被一层连续、致密的Cu₂O层所包覆,Cu₂O的存在是纳米Cu微晶颗粒自发氧化的结果。     

SnO2纳米棒的固相反应制备与表征

利用室温固相反应方法,合成了SnO2纳米颗粒前驱物.在NaCl、KCl等熔盐介质中,在600～785℃对前驱物进行焙烧,前驱物纳米颗粒自组装生长形成SnO2纳米棒.利用TEM、XRD和XPS对SnO2纳米棒形貌、成分进行了表征和分析,SnO2纳米棒直径为20～80 nm,长度从几百纳米到几个微米.研究了SnO2纳米颗粒前驱体熔盐介质中的生长,探讨了SnO2纳米颗粒在熔盐介质中的固相转变生长机理.     

阴离子交换合成氧化锌纳米晶体粉新方法及粉体光催化活性

采用一种新型的液相掺杂方法——非水相离子交换除氯法制备掺锑纳米氧化锌。该方法是在中性条件下,严格在控制含水量的低极性溶剂中进行的反应。氯离子的去除与水解是同时进行的,以保证掺杂的准确性及均匀性,提出的乙酸异戊酯共沸蒸馏法回收得到的纳米材料具有高分散性,TEM照片表明其保持了合成时的粒径和形貌。XRD图谱表明,未经煅烧的掺杂纳米氧化锌具有明显晶体衍射峰的晶体。掺杂后纳米氧化锌紫外可见吸收光谱发生了紫移,而紫外的吸收增强,表明锑原子已经掺杂到ZnO的晶格之中。这种半导体材料对甲基红（MR）的光催化降解作用表明,掺杂极大地提高了氧化锌纳米晶体的降解效率,90min内对甲基红（MR）的降解率可高达97％,与纯氧化锌相比,提高了70％以上。     

固相反应制备SnO2纳米棒技术研究

利用室温固相反应方法,合成了SnO2纳米棒前驱物.在NaCl和KCl等熔盐介质中,在660～785℃对前驱物进行焙烧,纳米颗粒前驱物自组装生长形成金红石结构的SnO2纳米棒一维材料.利用TEM和XRD对制备的SnO2纳米棒的形貌、成分进行了表征和分析,SnO2纳米棒直径为20～80nm,长度从几百纳米到几微米.分析了SnO2纳米颗粒前驱体熔盐介质中的生长,探讨了SnO2纳米颗粒在熔盐介质中的固相生长现象.     

SnO_2纳米颗粒的制备及其发光性能

用大分子网络凝胶法合成了氧化锡(SnO2)纳米颗粒。X射线衍射(XRD)结果表明,合成的SnO2纳米颗粒具有四方金红石结构,不含任何杂质相。扫描电镜(SEM)观察发现,制得的SnO2纳米颗粒形貌规整、呈类菱形。荧光光谱结果表明,在326 nm波长的光激发下,其荧光光谱由四个主发射带组成,其峰值分别位于379,417,450,470 nm。用230 nm波长的光激发,得到一个740 nm的荧光发射峰。基于实验结果,探讨了纳米SnO2的形成机理和发光机制。     

焙烧室温条件固相反应制备前驱物合成SnO2纳米棒的研究

室温条件下通过固相反应合成了SnO2纳米颗粒前驱物.在600～780℃对前驱物进行焙烧,在NaCl、KCl和KCl＋NaCl的熔盐介质中SnO2前驱物纳米颗粒自组装生长形成SnO2 纳米棒.利用TEM、XRD和XPS对SnO2纳米棒结构、形貌和成分进行了研究.结果表明SnO2纳米棒直径为20～80nm,长度从几百纳米到十几微米.分析了SnO2 纳米颗粒前驱体熔盐介质中的生长,利用固相转变生长可以解释SnO2纳米棒在熔盐介质中的生长机制.     

稀土La对化学共沉淀法制备纳米SnO2结构的影响

以SnCl4和LaCl3为原料,采用化学共沉淀法制备混杂La的纳米SnO2,运用DSC-TG、XRD和TEM等对混杂La的SnO2纳米粉末的物相和粒度进行了分析.结果发现:(1)采用化学共沉淀法制备混杂La的SnO2粉末,焙烧温度在400～650℃时,主要成分为SnO2,750℃以上焙烧,主要成分为La2Sn2O7和SnO2.(2)La混杂是通过阻碍SnO2由非晶体向晶体转变来抑制纳米颗粒长大,一旦晶体形成,并达到一个临界尺寸值时,La元素便开始脱溶析出,并反应生成La2Sn2O7,其对纳米晶粒长大的阻碍作用消失,晶粒将迅速长大.     

SnO2纳米颗粒制备及其对溶胶-凝胶Sb:SnO2薄膜性能的影响

以Sn(OEt)2为起始原料,采用水热晶化法合成了分散性良好的金红石结构的SnO2纳米颗粒.采用X射线衍射对其进行了表征,表明SnO2纳米颗粒的结晶性良好,颗粒尺寸小于10nm.将合成的SnO2纳米颗粒均匀分散到Sb:SnO2镀膜液中,经陈化后制成镀膜溶胶,以溶胶-凝胶浸渍镀膜工艺制备纳米颗粒掺杂Sb:SnO2薄膜.分别采用范德堡(Van Der Pauw)法、UV/VIS分光光度计和FTIR中红外分析仪测量并分析膜层的导电性能、光学性能及结构特征,研究了导电纳米颗粒添加对Sb:SnO2薄膜电性能、光学性能和结构的影响.     

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.……     

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...     

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.     

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.     

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