Ti(OC4H9)4-MAPS体系溶胶-凝胶转变研究

研究了Ｔｉ（ＯＣ４Ｈ９）４－ＭＡＰＳ体系中Ｔｉ（ＯＣ４Ｈ９）４、ＭＡＰＳ、Ｃ２Ｈ５ＯＨ、Ｈ２Ｏ４个原料组分对聚钛硅氧烷产转变规律的影响。结果表明,增大水和Ｔｉ（ＯＣ４Ｈ９）４的用量或降低ＭＡＰＳ和Ｃ２Ｈ５ＯＨ的用量,菜成凝胶;反之,则易形成溶胶。     

气相色谱法研究碳在氧阴极过程中的腐蚀

用气相色谱法研究和为氧阴极的碳材料在Ｎａ２Ｂ４Ｏ７和Ｎａ２Ｂ４Ｏ７－Ｎａ２ＣＯ３介质中腐蚀,结果表明,在较负电位下（－０．４－０．５Ｖ,０．１ｍｏｌ／Ｌ ＮａＯＨ）,检出ＣＯ和Ｃ瑟空白相同,说明碳腐蚀主要由电化学作用所致。     

电化学抛光对1Cr18Ni9Ti组织和性能的影响

研究了１Ｃｒ１８Ｎｉ９Ｔｉ不锈钢在Ｈ３ＰＯ４／Ｈ２ＳＯ４体系电解液中电化学抛光工艺和表面显微组织形貌及性能的关系。结果表明，电抛光后，１Ｃｒ１８Ｎｉ９Ｔｉ表层由机械抛光时的典型纤维组织转变为均匀致密的颗粒状组织，并因表层钝化膜的形成，其耐腐蚀性明显提高；同时表面光亮度比机械抛光时明显提高，可达到镜面程度，而冷作硬化层的去除，使表面显微硬度稍下降     

多功能NiO—SnO2气敏材料的敏感特性

采用化学共淀淀法合成了不同配比的ＮｉＯ－ＳｎＯ２气敏材料，用Ｘ射线衍射法分析材料的结构与组成，测试了元件的气敏性能，并利用表面催化作用较好的解释了材料的敏感机理，通过改变ＮｉＯ的掺杂量及气敏元件的加热功率，ＮｉＯ－ＳｎＯ２材料可分别实现对Ｈ２，Ｃ２Ｈ５ＯＨ的选择性检测以及对Ｃ２Ｈ５ＯＨ、Ｈ２、ＣＯ、Ｃ４Ｈ１０和汽油等气体的广谱检测。     

爆轰合成纳米超微金刚石的提纯方法研究

用炸药爆轰的方法制备了纲米超微金刚石,分别用ＨＣｌＯ４、Ｈ２ＳＯ４＋Ｋ２Ｃｒ２Ｏ２以及Ｈ２ＳＯ４＋ＫＭｎＯ４等多种方法对纳米超微金刚石进行了提纯研究。用Ｘ射线衍射、差热和热失重对不同提纯方法得到的超微金刚石进行了分析。结果表明,Ｈ２ＳＯ４＋ＫＭｎＯ４提纯是一种高效、经济、安全、污染小、投资少的提纯新方法。     

HF催化快速制备SiO2气凝胶

ＳｉＯ２气凝胶晃一种新型轻质纳米多孔泡沫材料,本文以正硅酸乙酯（ＴＥＯＳ）为原料,以乙醇为溶剂,以ＨＦ为催化溶胶－凝胶法快速制备出了ＳｉＯ２气凝胶。ＨＦ的加入大大加速了溶胶－凝胶反应速度,使凝胶时间减少至几分钟甚至更短;同时使凝胶温度降低至室温。ＢＥＴ及ＴＥＭ测试结果表明所制备的ＳｉＯ２气凝胶具有大比表面积（６７３．８ｍ＾２ｇ＾－１）、纳米多孔结构（骨架颗粒为几纳米,孔洞尺寸为５～３０ｎｍ）。     

ZrO2掺杂对SnO2薄膜电性及气敏性的影响

本研究不用金属醇盐而以无机盐ＳｎＣｌ２．２Ｈ２Ｏ为主体原料，以Ｚｒ（ＯＣ３Ｈ７）４为掺杂剂，无水乙醇为溶剂，采用溶胶－疑胶Ｓｏｌ－Ｇｅｌ）工艺制备了不同ＺｒＯ２掺杂份量的ＳｎＯ２薄膜，发现ＺｒＯ２薄膜在常温下对Ｈ２Ｓ气体具有较好的气敏性能，同时本文研究了ＺｒＯ２掺杂份量对ＳｎＯ２薄膜导电率及气敏性能的影响。     

用碳气凝胶作电极材料制作双电层电容器

双电层电容器具有极大的电容量和优良的充放电性能，这种新型储能器件有着广泛的应用前景。用微结构可控的纳米多孔导电材料碳气胶作为电极制作的双电层电容器的比电容达２５Ｆ／ｇ，其内阻在１Ω以下，漏电流小于１ｍＡ。     

亚临界干燥制备疏水SiO_2气凝胶

以Ｅ－４０（多聚硅氧烷）为硅源、三甲基氯硅烷的异丁醇溶液为干燥介质,用溶胶凝胶法,在亚临界条件下制备出疏水的ＳｉＯ２气凝胶．通过ＳＥＭ、孔径分布、比表面积、接触角以及红外光谱的测试对其物性进行了研究．结果表明,所制备的ＳｉＯ２气凝胶具有典型的纳米网络结构、比表面积大且具有疏水性能．亚临界干燥使得制备压力从６．４ＭＰａ降低到２．３ＭＰａ,降低了制备成本和风险,同时疏水性能提高了ＳｉＯ２气凝胶环境适应性,从而十分有利于气凝胶的商业应用．     

制备SnO2薄膜时原料中水对其成膜和光电性质的影响

用无水ＳｎＣｌ４和ＳｎＣｌ４．５Ｈ２Ｏ为原料，用热喷涂法制备ＳｎＯ２薄膜，在基片温度为５３０℃时，对所制得ＳｎＯ２薄膜进行了Ｘ－射线，ＳＥＭ分析，并对其发电性质进行测定，总结出含Ｈ２Ｏ的ＳｎＣｌ４制得的ＳｎＯ２薄膜生长速度快，电阻率低。     

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.……     

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 ...