利用废聚苯乙烯泡沫塑料制备改性乳液型胶粘剂

废聚苯乙烯泡沫塑料经洗净、干燥、粉碎、溶解、改性、乳化等步骤制备一种性能优异的木材纸张胶粘剂.对原料的用量、低毒性混合剂的选择和配比、改性剂的选择、乳化剂的选择、反应温度和反应时间的选择进行了优化试验.以乙酸乙酯、甲苯、丙酮为溶剂其最佳配比为:m(乙酸乙酯):m(甲苯):m(丙酮)=3:2:0.5.采用顺酐、丙烯酸对废聚苯乙烯进行改性试验.对酚醛树脂改性和邻苯而甲酸二丁酯增塑对其粘接性能的影响进行了探讨,确定酚醛树脂的最佳用量为3.0%～4.0%,邻苯二甲酸二丁酯的用量为8%～10%.用阴离子表面活性剂十二烷基硫酸钠和非离子表面活性剂OP-10作为乳化剂对废聚苯乙烯进行乳化改性.改性温度为(80±2)℃,反应时间为3～4h;乳化温度为70℃,反应时间为1～2h.     

废聚苯乙烯泡沫塑料的回收与利用——改性PS胶粘剂的研制

研究了溶剂、改性剂的选择及其用量以及反应温度对改性PS胶粘剂粘合性能的影响。     

羧基化改性聚苯乙烯微球的制备及对其聚乙二醇悬液的剪切增稠特性EI北大核心CSCD

以丙烯酸(AA)为改性剂,采用无皂乳液聚合的方法将其聚合接枝于聚苯乙烯(PS)微粒表面。使用红外光谱仪、热分析仪分析了其物性结构,使用扫描电子显微镜观察了粒子直径及阵列,使用接触角测量仪对比测试了PS粒子改性前后的接触角,分析了表面接枝基团对粒子亲水性能的影响。结果表明,改性后的PS粒子平均粒径为250 nm,表面富含羧基,亲水性得以改善。通过高能球磨法将合成的羧基化PS粒子分散在聚乙二醇200中,得到一种有机高分子体系的剪切增稠液(STF),分别采用动态流变仪和扩散波谱仪对其机械流变性能和微流变性能进行了测试,二者所测数据均表明流体具有显著的剪切增稠特性。     

羧基化改性聚苯乙烯微球的制备及对其聚乙二醇悬液的剪切增稠特性

以丙烯酸(AA)为改性剂,采用无皂乳液聚合的方法将其聚合接枝于聚苯乙烯(PS)微粒表面。使用红外光谱仪、热分析仪分析了其物性结构,使用扫描电子显微镜观察了粒子直径及阵列,使用接触角测量仪对比测试了PS粒子改性前后的接触角,分析了表面接枝基团对粒子亲水性能的影响。结果表明,改性后的PS粒子平均粒径为250 nm,表面富含羧基,亲水性得以改善。通过高能球磨法将合成的羧基化PS粒子分散在聚乙二醇200中,得到一种有机高分子体系的剪切增稠液(STF),分别采用动态流变仪和扩散波谱仪对其机械流变性能和微流变性能进行了测试,二者所测数据均表明流体具有显著的剪切增稠特性。     

无机有机材料对聚氨酯弹性体的改性研究

制备了一系列填料改性型聚氨酯(PU)弹性体,比较了几种无机填料(如硫酸钙晶须、白炭黑和蒙脱土等)和不同比例的有机材料如聚苯乙烯(PS)对PU弹性体物理机械性能和热性能的影响.研究结果表明:几种无机填料均能使弹性体的撕裂强度和耐热性能有不同程度的提高,但只有硫酸钙(CaSO4)晶须对提高拉伸强度有贡献.用不同比例的PS改性的PU弹性体,随PS含量的增加,耐热性有明显的提高,拉伸强度和撕裂强度先增加后降低.     

利用废聚苯乙烯泡沫塑料制备乳液型防水涂料

以废聚苯乙烯泡沫塑料为主要原料,甲苯、乙酸乙酯作为混合溶剂,用丙烯酸和丙烯酸丁酯对聚苯乙烯进行接枝改性,制备乳液型防水涂料.通过试验分别考察了混合溶剂的配比及用量、改性剂的选择、复合乳化剂的用量及增塑剂的用量对涂料性能的影响,并对涂料的质量进行了测试.     

亚微米核壳橡胶粒子改性聚苯乙烯——接枝度对形态结构及力学性能的影响

通过乳液接枝聚合技术合成不同聚丁二烯(PB)含量的聚丁二烯接枝聚苯乙烯(PB-g-PS)共聚物, 共混改性聚苯乙烯(PS), 使PB含量控制在20wt％。通过对接枝共聚物PB-g-PS接枝度的测定, 分析了不同接枝度对橡胶粒子分散状态以及橡胶粒子内部结构的影响, 考察了不同接枝度对改性聚苯乙烯力学性能的影响。通常认为橡胶粒子只有在1~3μm时才能对聚苯乙烯进行有效增韧, 然而实验结果表明, 使用粒径约为300nm的核壳橡胶粒子改性聚苯乙烯冲击韧性提高很大。此时, 接枝共聚物具有最佳核壳比PB/PS为70/30, 橡胶粒子呈均匀分散状态, 且最大冲击强度为124.9J/m, 相当于纯聚苯乙烯冲击强度的10倍。      

K2Ti6O13晶须改性硅酸盐无机胶粘剂的研究

以K2Ti6O13晶须为改性剂制备了一种改性硅酸盐胶粘剂.采用AG-250KNI电子精密材料试验机和DTG60H差热-热重分析仪对胶粘剂的力学性能和耐热性能进行了表征,采用常温水浸实验对胶粘剂的耐水性能进行了评价.结果表明,K2Ti6O13晶须有效的改善了胶粘剂的粘接强度、耐水性能和耐热性能.运用GBC10e紫外-可见分光光谱仪研究了K2Ti6O13对胶粘剂的改性机理.     

包装废EPS改性沥青研究

以回收的包装废聚苯乙烯发泡塑料(EPS)代替普通聚合物改性剂,对基质沥青进行改性,并对改性后沥青性能进行了研究.结果表明,改性后沥青软化点、5℃延度升高,针入度降低,基质沥青综合性能得到明显改善,并通过实验结果以及改性沥青微观结构的分析对包装废EPS改性机理进行了研究.     

纳米SiO2制备及改性

为了改善纳米SiO2的分散性,用溶胶-凝胶技术制备了纳米SiO2凝胶,并用不同改性剂对粉末进行了表面改性.采用透射电子显微镜(TEM)、X射线衍射(XRD)、粒度分析仪(PSA)、紫外-可见光分光光度计(UV-VS)等分析了纳米SiO2的粒径及分散性.结果表明,正硅酸乙酯的水解和缩合反应条件直接影响纳米SiO2粉体的粒径大小.KH-550硅烷偶联改性剂用量、改性时间等因素对改性效果有明显的影响.当改性剂用量为4.1%(质量分数),改性时间为2h时,可得到高分散性的纳米SiO2粉体.纳米SiO2粉末易发生团聚,只有对其进行表面改性,才能得到疏水性纳米SiO2粉末.     

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.     

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...     

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