溶胶-凝胶法制备纳米SiO2/丙烯酸酯预聚物

以3-氨丙基三乙氧基硅烷和三缩丙二醇双丙烯酸酯为原料,合成丙烯酸酯三乙氧基硅烷（APTP）,再用溶胶-凝胶法对其水解缩合制备纳米SiO2/丙烯酸酯预聚物（HAPTP）。对合成产物进行了表征,研究了APTP缩合水解对涂料及其固化膜性能的影响。结果表明,APTP经水解缩合后,有纳米SiO2生成。和APTP涂料相比,在相同的...     

UV固化皮革上光油的研制

合成了长链聚醚改性环氧丙烯酸酯(PEA)和柔性聚醚氨酯丙烯酸酯(PUA),作为UV固化皮革上光油的柔性预聚物,并进行了UV光油的配方优化实验。所研制的UV固化皮革上光油完全达到真皮革和人造革的涂饰要求。     

UV固化聚氨酯丙烯酸酯涂料的合成及性能研究

以聚乙二醇(PEG-400)为软段,以丙烯酸羟乙酯(HEA)和2,4-甲苯二异氰酸酯(TDI)为硬段,采用两步法合成聚氨酯丙烯酸酯(PUA),并研究其合成条件及力学性能。FTIR及~1H-NMR测试结果表明成功制备出PUA。实验结果表明,PUA合成的最佳条件为:第1步,反应温度为75℃,反应时间为3 h;第2步,反应温度为45℃,反应时间为5 h;阻聚剂的最佳质量分数为0.5%;将活性稀释剂1,6-己二醇二丙烯酸酯(HDDA)与三羟甲基丙烷三丙烯酸酯(TMPTA)按照质量比为1:1的比例加入PUA中,固化膜的凝胶率最高且综合性能优异;选用复合光引发剂体系时,固化膜的固化速率最高,其最佳质量分数为3%。     

水性UV固化涂料用多羟甲基苯酚丙烯酸酯的合成

以多羟甲基苯酚钠和丙烯酰氯为原料,合成了适用于水性UV固化涂料的多羟甲基苯酚丙烯酸酯,通过红外光谱表征了产物的化学结构。探讨了物料比、反应温度、反应时间和催化剂用量等因素对产物产率的影响,结果表明:当n(多羟甲基苯酚钠)∶n(丙烯酰氯)=1∶2、反应温度为0～-5℃、反应时间为2.5h、催化剂四丁基溴化铵用量为0.04%(占物料质量比)时,最有利于产物的合成;多羟甲基苯酚丙烯酸酯的水溶性及涂膜性能,也能较好地满足水性UV固化涂料的应用。     

甲基丙烯酸马来海松环氧树脂/聚氨酯丙烯酸酯/碳纳米管复合材料的制备和性能

为了保护环境和利用可再生资源,文中合成了甲基丙烯酸马来海松酸环氧树脂(MREMA)和聚氨酯丙烯酸酯(PUA),将MREMA和PUA按质量比1∶1进行UV固化反应,并用羟基多壁碳纳米管(HCNTs)改性制备纳米复合材料。利用红外光谱仪、热重分析仪、动态力学谱仪和漆膜测试仪等研究了碳纳米管对MREMA/PUA材料的热性能、动态力学性能以及涂膜性能的影响。结果表明,加入HCNTs可以明显改善材料的热性能和动态力学性能。加入0.5%HCNTs,材料的玻璃转化温度Tg达到173.4℃,与纯组分相比提高了64.6℃;加入0.7%HCNTs,材料的起始热分解温度提高了38.2℃。UV-光固化涂膜的硬度也因加入HCNTs而提高,且涂膜具有很好的物理化学性能。     

TGBAPS/MNA/EMI-24体系的固化行为研究

采用非等温动态示差扫描量热法(DSC)和热失重分析法(TGA)研究了N,N,N’,N’-四缩水甘油胺-3,3’-双(4-氨基苯氧基)二苯砜/甲基纳迪克酸酐/2-乙基-4-甲基咪唑(TGBAPS/MNA/EMI-24)体系的固化反应过程及固化物的热稳定性。由Kissinger方程和Ozawa方程求得该体系固化反应的表观活化能分别为84.1kJ/mol和87.1kJ/mol;由Crane方程求得固化反应近似为一级反应;TGBAPS/MNA/EMI-24体系固化物具有良好的耐热性能,其Tg为215℃,5%、15%和30%的失重温度分别为317℃、331℃和359℃。     

一种透明环氧改性有机硅树脂的制备与性能

采用二甲基二乙氧基硅烷与γ-(2,3-环氧丙氧)丙基三甲氧基硅烷为原料,经溶胶凝胶法,制备了透明的环氧改性有机硅树脂预聚物。将所得环氧改性有机硅树脂预聚物在4-甲基六氢苯酐为固化剂,二甲基苄胺为促进剂,经80℃固化1 h,120℃固化1 h,150℃固化2 h后,获得透明的环氧改性有机硅树脂固化物。研究了固化物的性能,结果表明,随着R/Si值增大,所得透明环氧树脂的透光率逐渐升高,但其硬度、玻璃化转变温度和热分解温度都逐渐降低。总体而言,当环氧改性有机硅树脂R/Si=1.6时,固化物具有很高的透光率,较好的热稳定性,可调的硬度,对基材有良好的粘接力,这表明所得环氧改性有机硅树脂有望用于光学透明器件的封装。     

端丙烯酸酯基超支化聚酯/聚氨酯丙烯酸酯体系的紫外光固化行为及性能

利用红外光谱(FT-IR)法研究了端丙烯酸酯基超支化聚酯(VHBP)/聚氨酯丙烯酸酯(PUA)体系紫外光固化反应,并研究了不同代数及含量VHBP对涂层性能的影响。结果表明,纯PUA达到最终双键转化率所需的时间最短,VHBP代数和含量高的体系时间较长。在PUA中加入VHBP后涂层硬度大幅提高,具有良好的综合性能,优于传统的PUA/环氧丙烯酸酯体系。随着VHBP含量的增加,涂层的硬度逐渐增大,耐冲击性和附着力有所降低。在相同VHBP含量时,硬度随代数的增加而逐渐降低。     

形状记忆聚氨酯丙烯酸酯的制备及性能

先以二元醇(1,4-丁二醇(BDO))引发ε-己内酯(ε-CL)开环聚合得到不同相对分子质量的4种聚己内酯二醇软段,再与六亚甲基二异氰酸酯(HDI)和甲基丙烯酸羟乙酯(HEMA)反应得到聚氨酯丙烯酸酯(PUA)。其中多元醇、二异氰酸酯和甲基丙烯酸羟乙酯的摩尔比为1∶2∶2。将制得的PUA溶于N,N-二甲基甲酰胺制备60%的溶液,加入光引发剂后紫外光固化制得聚氨酯丙烯酸酯薄膜。用傅里叶变换红外光谱、核磁和凝胶渗透色谱进行聚氨酯丙烯酸酯的结构和组成表征,通过差示扫描量热法、热失重分析、动态力学热分析(DMA)、力学性能测试等对PUA薄膜进行性能分析。并使用DMA的应力控制模式表征其形状记忆效应,发现当软段相对分子质量超过2000时,PUA膜具有极好的形状固定率和回复率,均高达98%以上,具有良好的重复性能。     

发光二极管封装用环氧树脂的制备与性能

以1,1,1-三(4-羟基苯基)乙烷(THPE)和环氧氯丙烷(ECH)为原料,合成具有较高折光率的三官能度环氧预聚物(TEP),其折光率为1.6002;由邻二氯苄和硫脲合成了既有芳香环又含硫的固化剂1,2-苯二甲硫醇(OBDMT),通过核磁共振对两者结构进行了表征。用OBDMT、常用含硫固化剂多硫醇(PCA)和传统固化剂甲基六氢苯酐(MHHPA)分别固化TEP成为3种固化体系。对3种固化体系进行了光学性能、耐热性能和力学性能的测试。结果表明,在环氧树脂中同时引入硫元素和苯环可以有效提高其折光率,TEP/OBDMT固化物折光率高达1.6420,具有较高的透光率(90%),很强的紫外光吸收能力,优异的热稳定性(玻璃化转变温度Tg=160℃,热分解温度=260℃)和良好的力学性能,可以应用于发光二极管(LED)封装领域。     

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