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1.
X射线映射成像包括吸收射线成像和衍射成像。吸收射线成像已在医学诊断、工业材料无损检测等领域得到广泛应用。衍射成像主要用来揭示具有相当高完整性(低位错密度)的单晶体内部的不规则结构和/或X射线波动范围,从而使其应用领域受到了限制。为了减少测试试样的局限...  相似文献   

2.
橡胶防泡剂     
娄成玉 《精细化工》1992,9(1):45-48
橡胶防泡剂是橡胶无压硫化配合体系中的一种功能性助剂。本文介绍了它的作用机理、制备方法、基本性质和主要应用。  相似文献   

3.
在过去的25年中,轮胎一直是采用X光技术进行检验的,目的是测定其内部结构的整体性。轮胎X光检验系统能够探测到常见的缺陷有:胎体帘布断线、交叉、接头不好、胎圈包布尺寸问题、带束级差及脱空。一般来说,X光检验系统可包括4个基本组成部分:X射线发生器、轮胎...  相似文献   

4.
X射线电缆     
木洋 《炭黑译丛》2003,(10):14-15
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橡胶填充剂的新发展   总被引:1,自引:0,他引:1  
龙志庭 《化学世界》1996,37(9):451-455
本文对近年来橡胶填充剂的发展进行了系统地论述。  相似文献   

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橡胶填充剂的新发展   总被引:2,自引:0,他引:2  
本文对近年来橡胶填充剂的发展进行了详细的、系统的讨论。  相似文献   

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《现代塑料》2009,(9):54-54
在医疗和工业领域,铅长期被认为是X射线装置不可缺少的制造材料。然而铅的不环保及难于处理的特性,使其在该领域的应用越来越受到限制。因此,市场迫切需要一种不含铅的防射线材料解决方案。  相似文献   

10.
周青山 《轮胎工业》1995,15(1):36-41
轮胎用橡胶的元素分析──X射线荧光分析法小谷真理奈田代育代石井子著周青山译刘登祥校前言轮胎用橡胶一般应能满足苛刻环境条件的要求。在胶料中添加各种配合剂,例如硫化剂、补强剂、填充剂、软化剂、防老剂和粘合增进剂等乃是为了改善轮胎的耐磨、耐切割、耐疲劳、耐...  相似文献   

11.
该文介绍Laursilicone新研发单组分液体硅橡胶,这种材料虽然尚处于商业化的早期阶段,但因其具有优良的物理性能和易使用性,未来的市场前景十分看好。  相似文献   

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The current generation of aircraft coatings had its basis in the polymer technologies of the 1970s and the use of chromate-based metal pretreatments and primers. There have been some incremental improvements in the epoxy and polyamide oligomers used in the primers as well as the isocyanates and flexible polyols used in topcoats, plus increases in the volume solids of the coatings to continue minimally meeting environmental requirements, but no truly new technologies have been developed and applied to aircraft coatings since that time. However, because of increasing economic and environmental pressures, this situation will soon change. Also, the U.S. Air Force is seeking a coating system that will have an ultimate lifetime of 30 years for maintenance cost control and fleet sustainability. The first change in the present coatings system will be in the pretreatments plus primers that currently constitute the metal protection system for the high strength Al alloys used for aircraft. For military aircraft, these alloys will continue to be Al 2024 T-3 and Al 7075-T6, heat-treated metals that have phase-separated regions rich in reactive metals such as Cu, Mg, and Zn. There are several new technologies now under consideration for such metal protection including conductive polymers as primers without Cr-based metal pretreatments, sol-gel based pretreatments and primers, plasma polymer metal pretreatments, and organo-modified aluminum oxide particles. Each of these technologies has shown some promise for Cr replacement, but each presently has a weakness that needs to be corrected for immediate usage. For the topcoat system, fluorinated polyols and improved use of UV-absorbers and light stabilizers will probably be the first changes implemented, with ceramer and other new crosslinking systems the most likely next polymer matrix candidates. The target for the entire coatings system is to have drastically improved wet-adhesion due to a covalently bonded system that has a gradient in composition that goes continuously from metal to metal oxide to mixed metal oxide/organic polymer to high-performance UV-stable organic polymer. The materials cost for such a system may be quite high, but the maintenance cost savings will much more than offset these costs. Presented at the 25th FATIPEC Congress, Sept. 19–22, 2000, in Turin, Italy. Department of Polymers & Coatings, Fargo, ND 58105.  相似文献   

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BACKGROUND: The reinforcement of elastomers by the addition of fillers is one of the most important aspects in rubber science and technology. In order to optimise the filler–polymer interface, innovative in situ generation of silica within isoprene rubber was carried out by means of a bottom‐up approach through a sol–gel process starting from tetraethoxysilane as silica precursor. The main aim was the study of the effect of the silica concentration and of the presence of coupling agent on the morphology and the dynamic mechanical behaviour of the composites. RESULTS: The in situ generated silica particles were homogeneously dispersed in the vulcanised rubber with dimensions from a few nanometres to the submicrometre scale. In the presence of coupling agent a good polymer–filler adhesion was observed. The dynamic mechanical behaviour was nonlinear for silica contents higher than 20 wt%. In this range of compositions silica exerted a marked reinforcement on the low‐amplitude storage modulus, which is related to the silica content according to the Huber–Vilgis model. CONCLUSION: Isoprene rubber can be effectively reinforced by the in situ generation of silica for silica contents higher than 20 wt%, and the interaction at the silica–rubber interface can be optimised by using suitable coupling agents. Copyright © 2009 Society of Chemical Industry  相似文献   

16.
动态生热是橡胶黏弹性的直接体现,是外加机械能向热能的转化。动态生热产生的热量积累直接影响材料的使用性能,生热导致的温度上升会降低橡胶复合材料的力学强度、静态和动态模量以及耐磨性等。为此,开展了橡胶复合材料动态生热机理及低生热调控方面的研究。本文从橡胶基体网络结构、强化粒子分散、加工工艺和理论模拟等角度出发,对橡胶低生热研究进行了归纳、总结及展望。  相似文献   

17.
The recent global agreement signed in Kigali to limit the use of hydrofluorocarbons (HFCs) as refrigerants, starting by 2019, has promoted an active area of research toward the development of low global warming potential (GWP) new refrigerants. Hydrofluoroolefins (HFOs) have been proposed as a low GWP alternative to third generation HFC refrigerants, but further work on fully characterizing them and their blends with other compounds is still required to fully assess their performance to replace the ones in current use. In this work, the polar and perturbed chain statistical associating fluid theory coupled with the density gradient theory is used to predict the vapor–liquid equilibrium, isobaric heat capacity, speed of sound, and surface tension of selected HFC and HFO‐based commercial azeotropic blends as fourth generation low GWP refrigerants, seeking for a predictive tool for these properties. © 2017 American Institute of Chemical Engineers AIChE J, 63: 250–262, 2018  相似文献   

18.
Interest in carbon fiber reinforced composites based on polyaryl ether ketones (PAEKs) continues to grow, and is driven by their increasing use as metal replacement materials in high temperature, high‐performance applications. Though these materials have seen widespread use in oil, gas, aerospace, medical and transportation industries, applications are currently limited by the thermal and mechanical properties of available PAEK polymer chemistries and their carbon fiber composites as well as interfacial bonding with carbon fiber surfaces. This article reviews the state of the art of PAEK polymer chemistries, mechanical properties of their carbon fiber reinforced composites, and interfacial engineering techniques used to improve the fiber‐matrix interfacial bond strength. We also propose a roadmap to develop the next generation of high‐performance long fiber thermoplastic composites based on PAEKs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44441.  相似文献   

19.
介绍了在当前技术上作了重大改进的3种新型除雾器的开发.DEMISTER@型713丝网除雾器,在干燥塔中使用可提高效率且具有较低的压力降;FLEXIFIBER(R)BD-LdP布朗扩散型烛式除雾器,在吸收塔中使用可减小压力降且无效率损失;FLEXIFIBER(R)ICK-LF碰撞型烛式除雾器,在干燥塔和二吸塔中使用可延长使用寿命且无效率损失.讨论了每一种类型除雾器的优点和局限性,以帮助管理者作出明智的决策,针对他们的具体要求选择最好的技术,同时也将比较不同选择所预期的安装、检修和操作费用.  相似文献   

20.
对防水片材挤出连续硫化生产线的四条管路做了改进。其中的硫化加热管路,设计了一套完整的油加热管路,取代了蒸汽加热管路,用户使用方便,节约能源,外观美丽,经济效益大增。  相似文献   

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