政策

<正>商务部裁定日本产氯偏树脂存在倾销商务部发布1月19日公告,公布对原产于日本的进口偏二氯乙烯—氯乙烯共聚树脂(氯偏树脂)反倾销调查的初步裁定。商务部初步裁定原产于日本的进口偏二氯乙烯—氯乙烯共聚树脂存在倾销,中国国内产业受到实质损害,且倾销与实质损害之间存在因果关系,并决定对原产于日本的进口偏二氯乙烯—氯乙烯共聚树脂实施保证金形式的临时反倾     

偏二氯乙烯共聚树脂的应用与开发

全文介绍了偏二氯乙烯共聚树脂的性能,生产的主要技术路线与最佳的操作条件及有关进展情况.对现工业化运行的主要偏二氯乙烯共聚树脂生产工艺的技术特点进行了具体的分析和总结,阐述了国内外研究开发的现状与发展趋势.并探讨了扩大应用范围等的前景与市场需求.     

浅谈国产PVDC树脂的性能及应用

聚偏二氯乙烯,英文名称是P01YV1ny11deneCh1or1de,缩写为PVDC,是偏二氯乙烯（VDC）与其他单体二元或三元共聚物的总称,其共聚的单体主要有氯乙烯、丙烯腈、丙烯酸和甲基丙烯酸酯类。通常,PVDC树脂是指偏二氯乙烯与氯乙烯的共聚物。PVDC树脂加工成的薄膜具有很高的阻隔性,而且耐高温蒸煮,因而被广泛应用于肉类、     

聚偏二氯乙烯在包装领域的应用

一、什么是聚偏氯乙烯材料 聚偏氯乙烯树脂（PVDC）,学名为“聚偏二氯乙烯”,是以偏二氯乙烯单体为主要成分的共聚物,是一种无毒无味、安全可靠的高阻隔性材料。除具有塑料的一般性能外,还具有耐油性、耐腐蚀性、保味性以及优异的防潮、防霉、可直接与食品进行接触等性能,同时还具有优良的印刷性能,广泛应用于食品、药品、军工等领域。     

聚合物乳液平均粒度及粒度分布的测定

在本工作中对苯乙烯—丙烯酸酯共聚物、氯乙烯-偏二氯乙烯共聚物、聚苯乙烯、聚醋酸乙烯及其共聚物乳液利用消光法及离心沉降法成功地测定了乳胶粒平均直径及直径分布。将该两种方法作了对比,并与电子显微镜法进行了比较。结果表明,消光法和离心沉降法对于测定聚合物乳液平均粒度及粒度分布均是切实可行、简便有效的方法。     

涤纶片基偏二氯乙烯三元共聚物底层的研究

一、前言为了在照相、电影工业方面研制新型材料——聚对苯二甲酸乙二醇酯(涤纶)以代替三醋酸纤维,我们研究了偏二氯乙烯水胶乳底层对涤纶片基的粘牢度及其透明度。由于涤纶片基具有疏水性、化学惰性等特点,因此和感光层不易结合。为此各国进行了大量研究工作。主要方法有表面处理和树脂打底法。表面处理有溶剂法、火焰法、电火花法以及氧化腐蚀法。在树脂打、底法中,按所用树脂种类,大致有以下几种:偏二氯乙烯共聚物、卤代乙烯脂类、     

食品包装用聚偏二氯乙烯(PVDC)片状肠衣膜

<正>ICS55.040 A82中华人民共和国轻工行业标准GB/T 17030—2019代替GB/T 17030—2008(参考文本)2019-05-10发布2019-12-01实施食品包装用聚偏二氯乙烯(PVDC)片状肠衣膜1范围本标准规定了食品包装用聚偏二氯乙烯(PVDC)片状肠衣膜的分类、技术要求、试验方法、检验规则、标志、包装、运输及贮存。本标准适用于以聚偏二氯乙烯树脂为主要原料,采用吹塑法制成的食品包装用聚偏二氯乙烯     

VMD片的显影研究

VMD片是作者在研究偏二氯乙烯-丙烯酸甲酯共聚物光解的基础上发展起来的的一种新的非银盐成像体系,它利用偏丙树脂光解过程中释放的氯化氢对铝膜的刻蚀作用,形成图像。本文报导了不同含氯量偏丙树脂和显影过程条件对VMD片灵敏度影响的研究,为建立最佳配方和最佳使用条件提供了可靠的依据。     

新型发泡材料——发泡偏氯乙烯共聚树脂

本文介绍一种新型的高分子发泡材料－－发泡偏氯乙烯共聚树脂，综述其合成、发泡、特性和用途。     

丙烯酸酯乳液原位接枝共混高抗冲聚氯乙烯的制备与性能EI北大核心CSCD

首先以丙烯酸丁酯、甲基丙烯酸甲酯为单体,1,4-丁二醇二甲基丙烯酸酯为交联剂,烯丙氧基壬基酚聚氧乙烯醚硫酸铵为反应型乳化剂,聚苯乙烯乳液为种子乳液,通过种子乳液聚合工艺,制得了粒径约200 nm且窄粒径分布的丙烯酸酯共聚物(ACR)乳液。然后将该ACR乳液直接加入氯乙烯的悬浮聚合体系中,制得了ACR乳液原位悬浮接枝共混型高抗冲聚氯乙烯(PVC)复合树脂。用红外光谱、差示扫描量热仪、扫描电子显微镜对树脂结构和形貌等进行了表征;考察了不同聚合温度下所得的ACR乳液对最终PVC复合树脂力学性能的影响;考察了悬浮聚合工艺中ACR乳液的加料顺序对悬浮聚合稳定性、PVC复合树脂的颗粒形态和力学性能的影响。结果表明,所得PVC复合树脂由ACR、氯乙烯在ACR上接枝所得共聚物及PVC均聚物组成,该原位增韧PVC复合树脂的抗冲性能提高非常显著。尤其是70℃乳液聚合所得ACR乳液用于氯乙烯的悬浮聚合,且当ACR质量分数为6.0%时的PVC复合树脂的缺口冲击强度可达常规SG-5型PVC树脂的7.4倍。此外,在氯乙烯单体液滴分散好后再加ACR乳液进行悬浮聚合,所得PVC复合树脂的颗粒形态和抗冲性能较好,且聚合过程中无粘釜、无粘轴现象。     

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...     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

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.     

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.……     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.