紫外光引发淀粉接枝丙烯腈反应动力学的研究

研究了在紫上光下以安息香乙醚为引发剂玉米淀粉接枝丙烯腈的反应。得到了经验接枝聚合反应速率方程Ｒｇ＝ｋ「ＡＮ」＾０．８７「ＢＥ」＾０．４４「ＡＧＵ」＾０．４１,测定了该光接枝过程的活化能Ｅｇ＝１４．９ｋＪ／ｍｏｌ。     

淀粉／甲基丙烯酸甲酯接枝共聚及生物降解性能研究

本文以硝酸铈铵为引发剂，研究了单体浓度、引发剂用量、反应温度和反应时间对淀粉与甲基丙烯酸甲酯（ＭＭＡ）接枝共聚反应特征参数的影响。当引发剂浓度为４．５×１０（－３）Ｍ／Ｌ，ＭＭＡ浓度为０．２２５Ｍ／Ｌ，在３０℃反应３．５ｈ时，单体转化率Ｃ％＝９０．５％，接枝率Ｇ％＝６２％，接枝效率ＧＥ％＝７０％，接枝支链的粘均分子量Ｍ＝×１０（－３）。接枝共聚物及其与聚氯乙烯（ＰＶＣ）共混物浇铸成膜后，用黑曲霉在无机盐营养培养基中降解４０天，失重率分别为３２％和２３％，表明淀粉／ＭＭＡ接枝共聚物可作为生物降解塑料使用。     

甲基丙烯酸与木薯淀粉接技共聚反应研究

以硝酸铈铵为引发剂，以南方地区特有的木薯淀粉与部分中和的甲基丙烯酸接枝共聚。研究了单体转化率、淀粉接枝率和接枝效率与甲基丙烯酸浓度、引发剂浓度、反应温度和时间、甲基丙烯酸中和度之间的关系。实验结果表明，单体浓度为１．５ｍｏｌ／Ｌ，引发剂浓度为１．０ｍｍｏｌ／Ｌ反应温度为５０℃，反应时间２ｈ，中和度＞８０％时，单体转化率和接枝率较高，单体中和度对接枝反应影响显著。     

过硫酸钾—脲氧化还原引发的甲基丙烯酸乙酯基三甲基氯化铵反…

研究了以ｓｐａｎ－８０为乳化剂和过硫酸钾－脲引发体系下，甲基丙烯酸乙酯基三甲基氯化铵反相乳液聚合的动力学，得出在「Ｋ２Ｓ２Ｏ８」为１２．３－７３．８μｍｏｌ．Ｌ＾－１．「ＣＯ（ＮＨ２）２」ｏ为０－０．９５ｍｍｏｌＬ＾－１，乳化剂为４１．７５－６６．８０ｇ．Ｌ＾－１范围内的聚合速率表达式：Ｒｐ＾∞「ＤＭ．ＭＣ」＾１．７１「Ｋ２Ｓ２Ｏ８」＾０．２８「ＣＯ（ＮＨ２）２」＾０．０１「３」＾－１．１８，ＢＣ     

淀粉在CS2/H2O2体系中与烯烃接枝共聚

采用ＣＳ２／Ｈ２Ｏ２体系在碱性条件下引发玉米淀粉与丙烯酰胺,苯乙烯接枝共聚,系统研究了ＮａＯＨ、ＣＳ２和单体的浓度、ＣＳ２／Ｈ２Ｏ２的摩尔比及反应温度等与接枝效应关系。结果发现在适宜条件下,室温（２５－３５℃）接枝反应０．５－１．０ｈ,单体转化率和接枝效率可达９６％以上。     

A3钢在环烷酸中腐蚀的物理化学行为

用失重法测定了不同温度下Ａ３钢在环烷酸中的腐蚀速率。将试验结果与热力学和动力学方程进行拟合，得到温度与腐以应速度常数方程为：ｌｎｋ＝９．４６－４．３６５／ｔ，环烷酸与Ａ３钢的反应表观活化能为：Ｅａ＝３４６ｋＪ／ｍｏｌ，摩尔反应为：Ｑ＝ΔＨ＝２５．２ｋＪ／ｍｏｌ。用簇集理论分析了环灶酸分子的缔合状态与Ａ３钢的腐蚀的关系。     

淀粉和丙烯酰胺的辐照接枝共聚反应研究

研究淀粉与丙烯酰胺在^60Coγ射线引发下的接枝共聚反应规律和反应机理,由实验结果得出了辐照时间与接枝聚合率的关系,辐照剂量率、单体浓度、淀粉浓度和辐照温度对接枝共聚反应速率的影响,并由此关联出接枝反应速率表达式：Rp=k[I]^1/2[AM][AGU]^1/2。对接枝共聚反应机理进行了初步探讨,推导的接枝共聚反应速率理论式与实验式一致。     

DBM-g-PE与PVC的相互作用研究EI

采用固相接枝法制备了ＤＢＭ－ｇ－ＰＥ，用红外光谱分析证明了接枝物确实存在。ＰＶＣ／ＣＰＥ＝１００／５合金性能测定结果表明，添加５份接枝物的合金（Ａ），缺口冲击强度、拉伸强度分别为１８．２ｋＪ／ｍ２和５３．０ＭＰａ；而添加５份ＰＥ的合金（Ｂ），其相应性能为５．１ｋＪ／ｍ２和３３．８ＭＰａ。不加接枝物的合金（Ｃ），虽有高韧性，但拉伸强度却由５３．０ＭＰａ降至５０．２ＭＰａ。ＤＳＣ、ＳＥＭ的结果均表明，ＰＥ接枝ＤＢＭ后与ＰＶＣ的相互作用增强，与ＣＰＥ协同作用能增韧、增强ＰＶＣ，并探讨了其机理。     

淀粉/BA-VAc接枝共聚物的合成及应用研究

以过硫酸铵为引发剂，研究了玉米淀粉与丙烯酸丁酯和醋酸乙烯酯接枝共聚合反应的规律。实验结果表明，单体浓度０．９７ｍｏｌ／Ｌ，引发剂浓度９．１×１０－３ｍｏｌ／Ｌ，反应温度６８℃，反应３ｈ时，反应体系的接枝率较高。通过红外光谱和Ｘ射线粉末衍射对接枝共聚物进行了结构分析。笔者以该接枝共聚物为基料，采用计算机辅助法设计出最优工艺配方，在国内首次研制生产出性能优异的功能性粘接材料     

高密度聚乙烯与丙烯酸乙酯辐射接枝共聚

研究了ＨＤＰＥ经预辐照法与丙烯酸乙酯接枝共聚。接枝度随辐照剂量和接枝时间而增加：Ｇ＝（１．５０ｔ＋２．１２）Ｄ＋３２．５３。单体浓度５０（质量）％、接枝温度３５℃为最佳接枝条件，在５５℃以下接枝表观活化能为２９．０３ｋＪ／ｍｏｌ。     

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.……     

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.     

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.