有机硅改性聚丙烯酸酯无皂乳液的合成及性能

利用无皂乳液聚合技术合成了有机硅含量不同的有机硅改性丙烯酸酯共聚乳液，通过对单体转化率及乳胶粒径的测定，发现有机硅单体的加入能提高硅一丙无皂共聚反应速率，减小乳胶拉拉径大小：结果还表明：合成共聚物的力学性能和耐水性随有机硅含量的增加而明显提高。     

有机硅氧烷改性丙烯酸酯乳液的制备及结构与性能研究

采用两步法合成了有机硅氧烷改性的丙烯酸酯乳液,并用差示扫描量热法、光电子能谱和透射电镜等方法对有机硅氧烷乳液及有机硅氧烷改性丙烯酸酯乳液的粒子形态、胶膜表面组成等进行了研究。结果表明,采用两步合成方法可制备稳定的有机硅氧烷改性丙烯酸酯乳液;在复合乳液中有机硅氧烷链段主要分布在粒子表面;在有机硅氧烷乳液中引入不饱和双键,则由于舍乙烯基的有机硅分子在第二阶段聚合过程中与丙烯酸酯分子发生接枝共聚．导致有机硅氧烷链段在表面富集程度降低。     

有机硅氧烷改性丙烯酸酯乳液技术研究进展

多官能团有机硅功能单体对丙烯酸酯乳液改性研究主要包括物理共混和化学共聚法,本文对有机硅改性丙烯酸酯乳液的研究方法进行了系统的综述.     

缩聚物/加聚物复合胶乳的制备科学Ⅱ.核壳结构聚氨酯-丙烯酸酯复合乳液的合成与表征

用合成的含羧基端羟基聚氨酯树脂，通过强外力乳化可形成稳定的水性聚氨酯乳液，与苯乙烯和丙烯酸丁酯等单体共聚，合成具有核壳结构的聚氨酯－丙烯酸酯接枝乳液，通过接枝乳液和共混乳液的性能差别对比，及DSC，FT－IR，粒径分析及力学性能测试分析表明，在聚氨酯－丙烯酸酯接枝乳液中，聚氨酯与丙烯酸酯发生部分交联形成稳定的核－壳结构，文中还对聚氨酯－丙烯酸酯接枝乳液的交联机理进行了研究。     

辐射引发种子乳液聚合制备硅氧烷/丙烯酸酯共聚乳液

采用^60Co γ-ray辐射引发种子乳液聚合法合成了聚有机硅氧烷(PSI)／丙烯酸酯共聚物乳液。通过TEM和IR分析对复合粒子微观形态和产物结构进行了表征,同时对乳胶膜的力学性能做了研究。结果表明,通过辐射引发PSI种子乳液聚合,制得了具有核壳式结构的P(SI—BA—MMA)共聚乳胶粒子。随着PSI含量的增加,复合乳胶膜的力学性能显著增强。     

新型有机硅改性丙烯酸酯乳液的制备及性能

为了解决常规有机硅单体在乳液聚合反应中易水解的问题,通过γ-甲基丙烯酰氧丙基三甲氧基硅烷(KH-570)和三甲基氯硅烷间的取代反应合成了一种难水解的新型有机硅单体γ-甲基丙烯酰氧丙基三(三甲基硅氧基)硅烷,再以其和丙烯酸酯类单体为原料,采用种子乳液共聚法合成了高硅含量有机硅-丙烯酸酯复合共聚乳液。采用傅里叶红外光谱(FTIR)、核磁共振(NMR)对新型有机硅单体进行了结构表征,利用红外光谱、表面接触角测试、热失重分析、拉伸测试等表征了乳液及乳胶膜性能。结果表明:新型有机硅改性丙烯酸酯乳胶膜比纯丙烯酸酯乳胶膜在耐水性、耐热性及力学性能等方面均有显著提高。     

高性能高硅烷含量硅丙复合乳液的研究

利用醇解反应，将γ-甲基丙烯酰氧基丙基三甲氧基硅烷中水解速度较快的甲氧基置换成水解速度较慢的乙氧基或异丙氧基，通过乳液共聚合成了高硅烷含量的硅丙复合乳液。用NMR，GC对硅烷单体进行了结构分析及转化率测试，并利用红外光谱对共降物进行了表征。研究了高有机硅含量对共聚物膜力学性能及吸水率的影响，证实了高含量硅烷组分能显著地提高丙烯酸酯乳液的物理性能。     

有机硅-丙烯酸酯共聚复合乳液的结构、形态及性能

利用红外光谱及扫描电镜对合成的有机硅氧烷-丙烯酸酯共聚复合乳液的化学结构、粒子形态进行了研究。结果表明,所合成的有机硅-丙烯酸酯复合乳液为一具有核壳形态结构的新型乳胶液,其核／壳问存在化学键合。通过与纯丙乳液和硅-丙共聚复合乳液薄膜性能分析与比较,发现有机硅-丙烯酸酯共聚复合胶乳膜在耐热老化性、耐水性及力学性能上有显著提高。     

塑料复合膜用水性聚氨酯胶粘剂的合成与表征

采用水性聚氨酯种子乳液与丙烯酸酯共聚的方法,制备了稳定的改性水性聚氨酯胶粘剂乳液,用FTIR及DSC分析表征了该共聚物的结构,通过改性聚氨酯胶粘剂粒度、乳液稳定性、耐水性、力学性能、粘接强度的测试,研究了丙烯酸酯含量及种类对水性聚氨酯乳液胶膜性能的影响.结果表明:丙烯酸酯的共聚加入改善了水性聚氨酯膜的耐水性、非极性基材之间的粘合力,当丙烯酸酯含量小于16%时,共聚物胶膜具有较好的力学性能.     

有机硅乳液的研究及进展

本文介绍了五种类型的有机硅乳液：聚硅氧烷乳液、硅微乳、聚硅氧烷／丙烯酸酯共混乳液、共聚乳液及复合乳液的制备方法，对各种乳液的性能及应用进行了综合评价，提出了有机硅乳液的发展前景。     

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.     

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.     

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     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to