改性酚醛环氧—PTFE耐磨防蚀涂层

介绍了一种改性酚醛环氧－ＰＴＦＥ耐磨防蚀涂层。这种涂层Ｔｉｍｋｅｎ试验机上于３１２Ｎ，２．５ｍ／ｓａ下耐磨寿命可达１３５００ｍ／μｍ，摩擦系数为０．１６－０．２０；在スウスト试验机上３ＭＰａ、０．２ｍ／ｓ，干燥空气和相对湿度为５０％中耐磨寿命均大于２．５×１０＾５周。经５％ＮａＣｌ盐雾试验１００ｈ后，底材与涂层的粘结强度，抗冲击强度及     

改性酚醛环氧－PTFE耐磨防蚀涂层

介绍了一种改性酚醛环氧－ＰＴＦＥ耐磨防蚀涂层。这种涂层在Ｔｉｍｋｅｎ（环－块）试验机上于３１２Ｎ、２．５ｍ／ｓ下耐磨寿命可达１３５００ｍ／μｍ，摩擦系数为０．１６～０．２０；在试验机上３ＭＰａ、０．２ｍ／ｓ、干燥空气和相对湿度为５０％中耐磨寿命均大于２．５×１０５周。经５％ＮａＣｌ盐雾试验１００ｈ后，底材与涂层的粘结强度、抗冲击强度及柔韧性等良好，低碳钢底材无锈蚀，可广泛应用于耐磨及防蚀等场合。     

NbCx-C三维网状纤维的制备

采用碳热还原法和不同的添加剂在温度为９７０￣１１２０℃,压力为０．１ＭＰａ的Ｎ２条件下,在石墨电阻炉内首次制备出ＮｂＣｘ（ｘ＝０．９８）－Ｃ三维网状纤维。三维网状纤维的直径为１２￣３８μｍ,网的环长为０．２２￣２．２ｍｍ,网孔径为７０￣７０１μｍ。本文详细研究了制备的工艺条件及相应的网状纤维的形貌。     

反应氯气气氛下卤化银光纤原料的超提纯

采用反应氯气气氛下水平区域熔融生长单晶的方法对卤化银原料进行超提纯,反应氯气气氛是由裂解低沸点碳氯化合物得到;化合物的通式为ＣＨ_ｎＣｌ_４－ｎ(ｎ＝０,１,２)．提纯的温度为４５０~５００℃,温区移动速度为０．２~０．８ｍｍ/ｍｉｎ;载流气体Ａｒ的流量为８０~１６０ｍＬ/ｍｉｎ．提纯后的卤化银原料红外吸收光谱显示,在４０００~８００ｃｍ^－１(２．５~１２．５μｍ)区域内的吸收随波长的增加而降低,中红外４０００~６００ｃｍ^－１(２．５~１６μｍ)区域是卤化银材料最佳的传输波段．用此原料制成的光纤可传输３．３~１６μｍ中红外光谱;传输１０．６μｍＣＯ_２激光的损耗为０．３~０．５ｄＢ/ｍ．     

Y2O3：Eu超微粉末的合成及发光性质研究

本文用络合－沉淀法制备了Ｙ２Ｏ３：Ｅｕ超微粉末，平均粒径０．０４μｍ－０．１μｍ，ＸＲＤ分析为立方晶系，试验结果表明，Ｙ２Ｏ３：Ｅｕ的平均粒径和相对亮率随焙烧温度的增加而明显增加；超微状态下的Ｙ２Ｏ３：Ｅｕ相对亮度低；Ｙ２Ｏ３：Ｅｕ的平均粒径对相对亮度有很大的影响。     

在Ag基体上用MOCVD法连续制备YBCO超导带

用ＭＯＣＶＤ法在Ａｇ基体上以－１５ｃｍ／ｈ的带速连续制备ＹＢＣＯ超导带，在８００－８５０℃之间沉积的样品均呈强裂ｃ－轴取向；而在７５０－８００℃间，ｃ－轴取向明显减弱，前者为不规则排列的大片状晶结构，而后者为不规则排列的小棒状晶和发育不育的片状晶，或者为小粒状晶集，所制亲品的Ｊｃ（７８Ｋ，ｏ）一般在０．５－１×１０＾４Ａ／ｃｍ＾２之间，最好的达到１．４×１０＾４Ａ／ｃｍ＾２。     

以球形α-Ni_(0.8)Co_(0.2)(OH)_2制备锂离子电池正极材料LiNi_(0.8)Co_(0.2)O_2

ＬｉＮｉ０．８Ｃｏ０．２Ｏ２是很有希望取代ＬｉＣｏＯ２的新一代锤离子电池正极材料．采用控制结晶法合成球形 α－Ｎｉ０．８Ｃｏ０．２（ＯＨ）２为前驱体,与 ＬｉＯＨ·Ｈ２Ｏ混合,在７００℃通Ｏ２热处理４ｈ合成锂离子电池正极材料ＬｉＮｉ０．８Ｃｏ０２Ｏ２粉末．Ｘ光衍射分析表明合成的ＬｉＮｉ０．８Ｃｏ０．２Ｏ２粉末结晶良好,具有规整的α－ＮａＦｅＯ２层状结构．扫描电镜分析表明粉末颗粒呈球形,粒径约８μｍ．粉末的流动性好,堆积密度高．充放电测试表明,合成的 ＬｉＮｉ０．８Ｃｏ０．２Ｏ２正极材料具有优良的电化学性能：首次充电比容量为１９７ｍＡｈ·ｇ－１,放电比容量为１７４ｍＡｈ·ｇ－１,１０次充放电循环后保持初始放电比容量的９６．６％．     

Ba6-3x(Sm1-yPry)8+2x Ti18O54微波介质陶瓷结构及性能的研究

本文研究了Ｂａ６－３ｘ（Ｓｍ１－ｙＰｒｙ）８＋２ｘＴｉ１８Ｏ５４（ｘ＝０．５,ｙ＝０．０、０．１、０．２）微波介质陶瓷的结构和性能。结果表明,在Ｓｍ－Ｐｒ系中Ｐｒ取代Ｓｍ形成了钨青铜结构的固溶体,随Ｐｒ取代量的增多,晶格常数呈线性增加趋势。最佳烧结温度确定为１４００℃。同时,随Ｐｒ的取代,介电常数得到提高,同时保持了低的损耗,并可以找到ｆ恰为零的最佳成分点。     

一种在于光三角法的激光测振仪

介绍一种基于光三角法的激光非接触测振仪,对激光测振仪的结构参数的优化设计进行了分析。研制的激光测振仪的主要技术参数为工作距离４０ｍｍ－２ｍ,测量范围２－５０ｍｍ,测量分辨力２－２２０μｍ频率响应０－３ｋＨｚ．     

一氧化碳和苯乙烯交替共聚物的合成与表征

利用乙酸钯和２，２′－联吡啶组成的催化剂体系催化一氧化碳和苯乙烯交替共聚合成出聚（１－氧代－２－苯基丙撑）（ＳＴＣＯ）。采用ＩＲ、ＮＭＲ、元素分析以及广角Ｘ光散射对该聚合物以表征。该共聚物晶体为单斜晶胞，晶胞参数为ａ＝１５．７×１０－１０ｍ，ｂ＝６．１７×１０－１０ｍ，ｃ＝７．４５×１０－１０ｍ，α＝９０．０°，β＝１０４．３°，γ＝９０．０°；晶胞体积为６９７．２×１０－３０ｍ３；空间点群为Ｐ２１／ｃ。此外，对该共聚物热降解进行了初步研究。     

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.     

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 ...