CVD聚合制备聚(羟甲基对亚苯基二亚甲基)及其性能的研究

用化学气相沉积(CVD)聚合法制备了聚(羟甲基对亚苯基二亚甲基)(PPX-HM)膜,采用FTIR和元素分析的方法证实了其化学结构.对膜溶解性和抗化学氧化性能的研究表明PPX-HM膜具有优异的耐溶剂性和抗化学氧化性能.对PPX-HM膜热性能的研究表明羟甲基的引入使得膜的玻璃化转变温度降低,室温柔性增强,动态力学阻尼性能增大,热降解起始温度比聚对亚苯基二亚甲基(PPX)低,但主链降解温度比PPX反而高出约50℃.此外,羟甲基的引入使得膜的亲水性能大幅度提高,水汽透过性能也有所提高.     

化学气相沉积聚合制备聚溴代对亚苯基二亚甲基及其性能的研究

用化学气相沉积(CVD)聚合法制备了聚溴代对亚苯基二亚甲基(PPX-B r)膜,采用FT-IR和元素分析的方法证实了其化学结构。对膜溶解性和抗化学氧化性能的研究表明,聚溴代对亚苯基二亚甲基膜具有优异的耐溶剂性和抗化学氧化性能。对其热性能的研究表明,溴的引入使得膜的玻璃化转变温度降低,室温柔性增强,热降解性能与聚氯代对亚苯基二亚甲基(PPX-C)相似。与PPX膜相比,溴的引入对膜的亲水性能影响不大,而水汽渗透率明显降低,具有更好的防潮性。     

CVDP制备的聚对亚苯基二亚甲基的表面磺化改性

采用化学气相沉积聚合(CVDP)的方法制备了聚对亚苯基二亚甲基(PPX)涂层,再通过发烟硫酸的化学表面改性成功地在PPX的芳香环上引入磺酸基团,可作为进一步功能化的反应基团.与PPX相比,表面磺化改性PPX(PPX-SO3Na)的接触角变小,亲水性增加,更有利于作为生物医用材料.采用原子力显微镜(AFM)测定PPX和磺化PPX的表面形貌,结果表明,表面磺化改性后的PPX变得更光滑,更有利于作抗凝血涂层材料.Fenton试剂测得PPX-SO3Na的抗化学氧化时间略低于PPX,但由于膜的主链主要是由苯环连接而成的,相对其它常用聚合物来说依然具有较好的抗化学氧化性能.     

含亚苯基甲基苯基硅树脂的合成及表征

以甲基、苯基氯硅烷和1,4-二(羟基二甲基硅基)苯为原料,采用水解-缩聚法合成了主链含亚苯基的甲基苯基有机硅树脂,并对其结构和性能进行了研究。红外光谱(FT-IR)和核磁共振(29Si NMR)分析表明,亚苯基被成功引入到硅树脂主链中。差式量热扫描(DSC)分析表明硅树脂为均聚物。热失重(TG)结果表明,在N2氛中,硅树脂在450℃失重约1%,优于普通甲基苯基硅树脂。硅树脂的清漆涂层在300℃下使用时,附着力、抗冲击、柔韧性能仍保持良好。电化学阻抗分析(EIS)结果表明,硅树脂的清漆涂层常温固化后、经300℃的高温烘烤后都具有优良的耐腐蚀性能。     

片状ZnO/还原氧化石墨烯复合材料的制备及其可见光降解亚甲基蓝性能研究

利用化学浴沉积法合成的ZnO为前驱体,并加入不同含量的氧化石墨烯(GO),再采用经过300℃氮气氛围煅烧法,最终得到ZnO-热还原氧化石墨烯复合物(ZnO/RGO)。对合成样品进行一系列分析测试,并测试了样品的光催化性能。结果表明:掺杂0.8%-RGO的ZnO/RGO(ZRG)复合物的光催化活性最高,可见光照4h对亚甲基蓝(MB)的降解率达到87.7%。同时,探讨了不同条件下对光催化降解亚甲基蓝(MB)的影响,通过捕获剂实验表明,光催化降解MB的活性物种主要是超氧自由基O^-₂·和空穴h⁺。     

TiO2纳米管阵列的表征及光催化性能的研究

采用电化学刻蚀技术在纯钛板表面构筑有序结构的纳米TiO2管膜层.用Raman、SEM对表面产物进行分析和表征.结果表明当热处理温度为450℃时,TiO2纳米管膜的晶相结构绝大部分为锐钛型,当热处理温度为600℃时,TiO2的晶相结构转变为金红石型.20V电压下阳极氧化得到管径约为80～90nm,长度约400nm的高密度排列的有序TiO2纳米管.以亚甲基蓝为研究对象,紫外石英杀菌灯为光源,研究阳极氧化法制备的TiO2光催化剂的光催化性能.     

主链含柔性亚甲基苯并二噁唑类聚合物的合成及性能研究

设计并合成了一系列含有苯并噁唑环和不同CH2链长的刚、柔间隔聚亚甲基苯并二噁唑（PBOCx）聚合物，并对它们进行了结构表征，同时对聚合物的溶解性能和热性能进行了探讨．研究表明，在主链上引入亚甲基结构可以在一定程度上提高聚合物的溶解性，其中PBOC4显示了良好的溶解性能，但随着亚甲基数目的增加，聚合物的溶解性能有下降趋势；虽然有柔性链段的引入，分解温度降低，但是PBOCx仍具有很高的热分解温度，在450℃以下表现出良好的热稳定性．     

氧化石墨的制备及其对亚甲基蓝的吸附研究

采用Hummers法制得了氧化石墨,研究了氧化石墨对低浓度的亚甲基蓝溶液的吸附作用,探讨了氧化石墨的用量、pH、温度等对吸附的影响,以XRD和FT-IR对吸附前后的氧化石墨进行了表征。对吸附过程的动力学拟合表明吸附符合一级反应的动力学,吸附活化能E=71.73kJ/mol,指前因子lnA=24.93。结果表明吸附为化学吸附,吸附率约91%,吸附量为4.2mg亚甲基蓝/g氧化石墨。     

还原氧化石墨烯负载极性面占优氧化锌对亚甲基蓝的光催化降解

采用光还原方法将氧化石墨烯负载在极性面占有的氧化锌六棱盘上合成出氧化锌-还原石墨烯复合光催化材料。在紫外-可见光辐照下,该复合材料的光催化降解亚甲基蓝活性得到明显提高。光催化性能的提高主要归因于还原氧化石墨烯对光生电子的捕获抑制了电子和空穴的复合以及还原氧化石墨烯对亚甲基蓝分子的有效吸附。还原氧化石墨烯的最优负载量约为2%,同时负载的还原石墨烯对光的吸收可在一定程度上减少复合材料对光子的利用率。     

纳米碳纤维的固化及其亚甲基蓝吸附性能

采用化学气相沉积法(CVD),以甲烷为碳源,金属镍为催化剂,550℃下在不同基体材料(SiO2纤维、蜂窝陶瓷体)上合成了纳米碳纤维。通过场发射扫描电镜(FE-SEM)和X射线粉末衍射仪(XRD)对固化在2种不同基体材料上的纳米碳纤维的形貌和晶相组成进行了表征。对比考察了固化在2种不同基体材料上的纳米碳纤维对亚甲基蓝的吸附性能影响。结果表明,相比于蜂窝陶瓷体,SiO2纤维更容易生成大量致密有序的纳米碳纤维层,并且所得到的复合材料具有更优的吸附亚甲基蓝的反应性能。     

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