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1.
In this paper an application of thermogravimetric-derivative thermogravimetric analysis (TG-DTG) to the measurement of the nitroglycerin (NG) in thc coating of the rocket propellant was developed. In comparisons with gas chromatography (GC) and weight method (WM), TG-DTC has been confirmed to he even more available to measure rapidly migration of NG in thc coating. The new method is accurate to within ± 0.5% and its standard deviation is O.1. The method is of actual significance in respect of thc investigation of the migration regularity of plasticizer, the selection for coating materials and the prediction of service life of the solid propellants.  相似文献   

2.
对改善推进剂工艺性能的文献进行了综述,包括对异氰酸酯改性、固化催化体系、工艺助剂和添加螯合剂的研究等,建议以三苯基铋延迟快速固化催化体系为基础,综合各种延长适用期、改善工艺性能的方法,解决二聚酸二异氰酸酯(DDI)在实际应用中的问题,推动DDI的实用化进程。  相似文献   

3.
杜永强  郑坚  彭威  张晓  顾志旭 《化工进展》2016,35(Z2):219-224
HTPB复合固体推进剂是火箭发动机的动力之源,其贮存寿命和性能优劣决定了火箭发动机的寿命和作战性能的发挥,因而研究HTPB复合固体推进剂的贮存老化模型及寿命预估具有重要的军事和经济意义。本文对复合固体推进剂贮存老化性能的研究方法进行了介绍,并综述了国内外贮存寿命老化建模的研究进展,针对推进剂实际贮存可能出现的问题对未来贮存寿命预估的发展趋势进行了预测。研究结果表明,现代仪器的运用可以弥补传统仪器在固体推进剂老化性能研究上的不足,但是还存在研究手段单一、测试方法存在误差、没有形成统一的系统等缺点;推进剂的老化过程比较复杂,结构完整性分析和老化试验相结合的方法可以对推进剂贮存性能和寿命预估进行系统性的研究,得到的结果更准确,可靠性更高。分段老化建模作为推进剂寿命预估研究的新方向,具有很大的发展空间。  相似文献   

4.
The migration of the plasticizer, dioctyl adipate (DOA) in the accelerated ageing of composite propellant has been studied. The method is based on the extraction of DOA with carbon tetrachloride and its estimation by gas chromatography. The concentration of DOA in the propellant at different distances from the insulation was determined after a definite ageing period and compared with the initial DOA concentration. The effect of (a) the ageing period, and (b) the ageing temperature on the degree of migration was examined. The present studies confirm the existence of plasticizer migration in the propellant adjacent to the insulation, during ageing.  相似文献   

5.
To understand the changes occurring in solid propellants on storage under space environments, the effect of vacuum and radiation on different propellants were studied. It was found that propellants lost weight on vacuum storage and that the rate and extent of weight loss depended upon the plasticizer content, the exposed surface area and the vacuum level. Mechanical properties and burning rates were practically unaffected and the effect on thermal decomposition was marginal. On the other hand, irradiation with gamma rays resulted in a drastic deterioration of mechanical properties and in a large increase in the rate of thermal decomposition at 225 °C. Radiation had no effect on burning rates.  相似文献   

6.
花永春 《工业催化》2002,10(4):16-22
根据对化肥生产中在线催化剂的优化操作模拟计算及使用寿命预测的应用实例,说明充分发挥计算机的作用,在提高化肥催化剂的使用技术中具有重要的现实意义。  相似文献   

7.
着重分析影响固碱锅使用寿命的因素:碱液的起始浓度、最高熔碱温度、火焰加热方式、升温速度等,提出了延长固碱锅使用寿命的措施。  相似文献   

8.
固相微萃取是一种简单高效的新型预处理技术,涂层作为萃取头的核心部分,在萃取过程中发挥着重要作用。本文对涂层进行了概述,介绍其萃取机理、涂渍技术以及新型涂层研究发展与应用的情况。  相似文献   

9.
A study has been conducted to investigate the relationship between binder molecular structure and the mechanical/rheological properties of solid propellants. Beginning with the mechanical property requirements dictated by the motor grain operating conditions as well as rheological constraints imposed by available processing technology, the approach taken was to work backwards to obtain the ideal molecular structure of a solid propellant binder. Structural/processing requirements were determined from the demands of three typical rocket motor applications: space transfer, launch vehicle/ballistic missile, and tactical air-to-air. Three general formulation approaches to meet the demands of these applications were considered. These include traditional composite and nitrate ester plasticized formulation approaches, in addition to a hypothetical all-binder propellant. For each of these three formulation approaches, a variety of polymer molecular characteristics were defined in terms of molecular weight, crosslink density, solubility parameter, chain stiffness, monomeric friction coefficient, volume fraction filler, and volume fraction plasticizer. Characterization data for ten polymeric binder systems are reported to show how their molecular architecture influences the resulting propellant properties.  相似文献   

10.
介绍了天津渤天化工有限责任公司固碱锅的使用情况,分析了损坏原因,提出了延长固碱锅使用寿命的措施。  相似文献   

11.
从纳米含能材料、纳米金属粉、纳米催化剂及纳米碳材料4个方面综述了纳米材料在固体推进剂中的应用进展,归纳了各类纳米材料的特点及其在固体推进剂应用中存在的问题。指出了未来的研究方向,如纳米材料在固体推进剂中的分散技术、影响纳米材料微观形貌和粒度的因素、纳米材料在固体推进剂中的催化作用机理及利用纳米材料改善固体推进剂的力学性能等。  相似文献   

12.
简介了二聚酸二异氰酸酯(DDI)的主链结构及物性指标,详细叙述了DDI在丁羟(HTPB)推进剂药柱及绝热层、衬层、隔层中的应用情况,同时概括了其在聚醚推进剂和聚酯推进剂中的应用进展,认为绿色、无毒及来源于可再生原料的DDI是开发双推力推进剂、固体脉冲推进剂、富燃料推进剂及大型固体航天助推器推进剂的重要原材料,进行DDI的开发和应用对提高我国战术、战略武器的性能具有极大的促进作用。  相似文献   

13.
高能固体推进剂用粘合剂的研究进展   总被引:7,自引:0,他引:7  
较为系统的从双基推进剂、复合固体推进剂、改性双基推进剂和NEPE推进剂等方面综述了其所用粘合剂的种类及其研究发展概况。介绍了当今新型含能粘合剂的类别和发展状况,并根据目前推进剂的发展要求,指出其粘合剂的发展趋势是含能化的热塑性弹性体。  相似文献   

14.
综述了近年来固体推进剂热安全性的研究进展,认为固体推进剂发生热爆炸主要是由于推进剂生热速率大于散热速率导致热量累积。影响推进剂热安全性的因素主要由其组成、形状和尺寸等内因,以及贮存环境、老化时间等外部因素构成。固体推进剂热安全性研究多采用分析仪器与实验相结合的方法,借助计算机模拟仿真研究将是今后固体推进剂性能研究的重点。  相似文献   

15.
为满足目前固体火箭推进剂在应用过程中产生的环境相容性要求,对几种无氯氧化剂在洁净固体推进剂中的应用进行了综述。针对固体推进剂燃烧产物中HCl对环境产生的危害,分析了几类推进剂的抑氯机理,并着重从氧化剂的角度介绍多种无氯高能氧化剂在固体推进剂中的应用,分析了无氯氧化剂的特点及在推进剂应用过程中面临的问题,提出了洁净固体推进剂的重点研究方向,促进洁净固体推进剂的广泛应用,降低HCl对环境的危害。  相似文献   

16.
Electrochemical impedance spectroscopy (EIS) is used to derive an expression for predicting the service life of organic coating in a C4-type environment (industrial and costal areas with moderate salinity) as defined in ISO 12944 standard for paints and varnishes—corrosion protection of steel structures by protective paint systems. Three coating systems with a record of 2, 5, and 10 years of durability were selected for the study. The selection was also based on proven composition and dry film thickness (DFT) of the coatings as per ISO 12944. Electrochemical impedance measurements of the paint-coated panels were carried out by exposing the coated mild steel panels without scribe in different corrosive environments such as immersion in NaCl solution, neutral salt spray, etc. Neutral salt spray exposure was found to be the most severe corrosive environment among all the three coating systems. In most of the cases, EIS gave early indication of coating failure when compared to visual defects such as blistering and over-film corrosion.  相似文献   

17.
The ignition of a solid propellant in water by means of an unsealed system of ignition in the form of an open channel with a heating coil placed in the channel is considered. The ignition system operates according to the principle of creation of extreme conditions of water boiling in the channel with heat supply from an electrical heater. It was established visually that the heating of the walls is preceded by a preliminary period connected with the change in the state of aggregation of water. The system was tested on solid-propellant specimens. Translated fromFizika Goreniya i Vzryva, Vol. 35, No. 3, pp. 52–57, July–August 1999.  相似文献   

18.
橡胶的热氧加速老化试验及寿命预测方法   总被引:10,自引:3,他引:10       下载免费PDF全文
胡文军  刘占芳  陈勇梅 《橡胶工业》2004,51(10):620-624
简介橡胶的热氧加速老化试验和寿命预测方法。采用加速老化试验预测橡胶寿命的理论基础是时温等效原理和扩散限制氧化(DLO)模型;时间一温度叠加的理论模型常用系列试验曲线求解Arrhenius活化能.确定平移因子。,通过平移试验曲线得到任一温度下橡胶的寿命;扩散限制氧化模型通过一系列试验确定橡胶中氧气的浓度与橡胶模量的关系,再通过测定橡胶中氧气的浓度预测橡胶的寿命。  相似文献   

19.
20.
葛成章  刘英 《氯碱工业》2002,(11):11-13
以太原化工股份有限公司氯碱分公司离子膜分厂F2型离子膜电解槽实际运行参数为依据,对该种电解槽的阴、阳极活性涂层性能衰减情况进行经济分析,并计算出电解槽活性涂层的最佳经济寿命。  相似文献   

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