阻燃剂水镁石的表面改性研究

使用铝酸酯、钛酸酯、硬脂酸3种偶联剂对水镁石进行表面改性。阐述了改性剂用量、时间和温度等因素对水镁石改性的影响。硬脂酸用量5%,改性温度80℃,改性时间80min条件下,产物性能最优良,活化指数达到96.2%。钛酸酯用量1%,改性温度60℃,改性时间50min条件下,产物性能最优良,活化指数达到98.2%。铝酸酯用量1%,改性温度70℃,改性时间50min条件下,产物性能最最优良,活化指数达到98.8%。使用XRD、FTIR和TG-DSC对改性前后的水镁石进行表征。分析结果表明改性剂对水镁石的改性机理是:改性剂分子与水镁石表面的羟基形成氢键而吸附在水镁石的表面,从而改善了水镁石与聚合物的相容性能。     

氨基酸改性支链淀粉/丙烯酰胺共聚物的制备及其抑菌性的研究

以玉米支链淀粉、丙烯酰胺为原料,合成了淀粉接枝丙烯酰胺共聚物.利用氨基酸对淀粉接枝丙烯酰胺共聚物进行了改性,并对反应条件进行了研究,得出了最佳条件为:pH值为11,反应温度70℃下反应10h,最佳条件下氨基酸转化率为24.2%.对改性产物通过菌落计数法进行抑菌实验,实验表明该产物具有一定抑菌效果.     

交替共聚物改性甲壳素对染料吸附性能的初步研究

利用苯乙烯-马来酸酐交替共聚物(SMA)与半脱乙酰甲壳素共混改性,制得交替共聚物改性甲壳素。产物用红外光谱、固体13 C-NMR和综合热分析进行表征,结果表明甲壳素C6位上的醇羟基与交替共聚物的羰基反应形成酯。探讨了染料初始浓度、改性产物投料量、吸附时间和温度对吸附性能的影响。结果表明,25℃时产物对中性红(NR)、次甲基蓝(MB)和孔雀石绿(MG)的最大吸附量分别为1281、984和1725mg/g;对NR的去除率最大,在20℃,吸附时间为30min时,吸附达到平衡,对NR溶液脱色率达到98%。     

微胶囊壁材用三聚氰胺甲醛树脂的改性及性能研究

制备出问苯二胺、间苯二酚改性三聚氰胺甲醛树脂.利用红外光谱测试表征产物的结构;通过热失重仪和差示扫描量热器测定了树脂的热失重率以及相变焓,研究了改性后树脂的热稳定性的变化.结果表明,经过化学改性后,三聚氰胺甲醛树脂分子引入苯环结构,使树脂在300℃左右的热稳定性得到提高.     

废弃对位芳纶粉末表面烷基化改性研究

对废弃的低相对分子质量对位芳纶(PPTA)粉末进行烷基化改性，以改善PPTA的化学惰性，研究了溶剂对烷基化产物表面接触角和溶解性能的影响，通过红外光谱仪、热重分析仪、比表面积及孔径分析仪、扫描电子显微镜对目标产物进行了表征。结果表明，以N-N二甲基甲酰胺、二甲亚砜(DMSO)作为溶剂时，PPTA粉末烷基化改性效果良好。为此通过正交试验对比了使用2种溶剂合成的烷基化产物的接触角，确定了最佳溶剂为DMSO,优化出适宜的改性工艺条件：溴代正丁烷与PPTA粉末质量比为3.5∶1,氢化钠质量分数为0.4%,反应时间为4.5h,反应温度为80℃,在此基础上进行3次重现性实验，烷基化产物接触角平均值为117.26°。     

PP包装膜胶粘剂的研究

以过氧化二苯甲酰(BPO)为引发剂,通过自由基聚合,采用马来酸酐(MAH)接枝改性氯化聚丙烯(CPP);研究了不同反应温度、不同反应时间和不同质量的MAH和BPO对改性PP包装膜的粘附性能的影响;得出较佳的工艺条件为反应温度85℃,反应时间2.5h,原料质量配比为m(CPP):m(MAH):m(BPO)=100:2.5:0.4.并对产物结构进行了FTIR表征.     

NaOH/尿素溶液屏蔽木粉羟基制备注塑级生物基塑料

为了解决石化资源日益紧缺和开发石化资源带来的环境污染,以可再生的农林废弃物胡桑枝条为原料制备了可注塑的生物基塑料.将球磨预处理的胡桑枝条粉放置在预冷的NaOH/尿素溶液中以-10 ℃溶解润胀1 h后,在捏合机中常温捏合,冷冻干燥得到捏合改性产物.捏合改性产物与一定量的甘油共混挤出制备生物基塑料.研究了不同溶液配比、甘油用量和甘油共混方式对改性产物力学性能的影响.结果表明:球磨木粉经过复合溶剂NaOH/尿素溶液体系捏合改性后,具有热塑性,加入甘油捏合或加入甘油共混挤出,能得到具有较好力学性能的生物基塑料,所制备的生物基塑料弯曲强度最大达到26.10 MPa,拉伸强度和断裂伸长率分别达到13.21 MPa和10.91%.以胡桑枝条木粉为原料,在NaOH/尿素体系中进行捏合改性后,木粉中羟基被屏蔽,结晶度降低,加入甘油增塑可制备出注塑级生物基塑料,实现了木粉的全组分高效利用.     

改性石膏对磷渣混凝土强度激发作用的研究

本文通过实验手段,研究了改性石膏对磷渣混凝土强度的影响,并结合XRD、SEM分析改性石膏-磷渣混凝土水化产物的结晶形态和矿物组成。结果表明：在磷渣粉掺量相同的情况下,加入天然石膏、120℃烧石膏、550℃烧石膏激发剂后,水化产物主要是水化硅酸钙、钙矾石,因此,磷渣混凝土抗压强度有了不同程度的提高,其中外掺6%的550℃烧石膏作激发剂的磷渣混凝土抗压强度最大。     

聚醚改性聚硅氧烷的合成及其表面活性研究

利用聚醚链末端的羟基与丁二酸酐开环反应生成末端含有羧基的改性聚醚,利用合成的聚醚链末端的羧基与亚硫酰氯反应得到链末端含有酰氯基的聚醚,再通过酰氯基与羟基硅油链末端的羟基反应合成了聚硅氧烷聚醚表面活性剂.采用红外、热分析、GPC等手段对合成产物进行了结构表征.通过表面张力的研究获得了聚醚改性聚硅氧烷表面活性剂在25℃时的临界胶束浓度CMC约为0.01g/mL.     

氧化石墨烯改性环氧隔热涂层的耐蚀和隔热性能研究

用氧化石墨烯(GO)浓缩浆分散法制备GO改性环氧隔热涂层，在浓度(质量分数)为3.5% 的NaCl溶液(50℃)中进行腐蚀实验并测试其腐蚀前后的隔热性能。432 h的腐蚀电化学测试结果表明，用0.5%(质量分数) 的GO改性显著提高了涂层低频阻抗，涂层的耐蚀性优于无GO改性和1.0% GO改性的涂层；SEM分析结果表明，用0.5%和1.0% GO改性的隔热涂层腐蚀432 h后表面形貌完好，涂层/基体界面处没有出现裂纹和腐蚀产物，而未经GO改性的涂层出现了明显腐蚀破坏。腐蚀试验前，0.5%、1.0% GO改性的涂层与没有改性的涂层的隔热性能没有明显的区别；腐蚀432 h后涂层对250℃热源分别降温98℃、123℃、115℃，粘结强度分别降低了3.9、1.0、2.3 MPa。实验结果表明，用0.5% GO改性的涂层耐蚀和隔热性能最好。     

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.     

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 ...     

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.