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目前正在进行研制石墨材料,准备用于MX 第一级和第二级固体火箭喷管的入口部,喉部,后喉部,出口锥和可延伸出口锥。这些材料必须经受住新型洲际弹道导弹(ICBM)喷管系统的苛刻的结构、化学侵蚀,粒子冲刷和高温环境。该系统的燃烧室压力可达127公斤/厘米~2,火焰温度为3700°K 至3922°K。叙述了第一级和第二级全尺寸试验喷管的现状。还提出了在喷管设计、石墨材料研制以及预期性能改进方面进一步工作的方向。 相似文献
4.
A strategy is being developed whereby the current set of internationally standardized space data communications protocols can be incrementally evolved so that a first version of an operational "Interplanetary Internet" is feasible by the end of the decade. This paper describes its architectural concepts, discusses the current set of standard space data communications capabilities that exist to support Mars exploration and reviews proposed new developments. We also speculate that these current capabilities can grow to support future scenarios where human intelligence is widely distributed across the Solar System and day-to-day communications dialog between planets is routine. 相似文献
5.
Green AR Andrews HR Bennett LG Clifford ET Ing H Jonkmans G Lewis BJ Noulty RA Ough EA 《Acta Astronautica》2005,56(9-12):949-960
In light of the importance of the neutron contribution to the dose equivalent received by space workers in the near-Earth radiation environment, there is an increasing need for a personal dosimeter that is passive in nature and able to respond to this neutron field in real time. Recent Canadian technology has led to the development of a bubble detector, which is sensitive to neutrons, but insensitive to low linear energy transfer (LET) radiation. By changing the composition of the bubble detector fluid (or “superheat”), the detectors can be fabricated to respond to different types of radiation. This paper describes a preliminary ground-based research effort to better characterize the bubble detectors of different compositions at various charged-particle accelerator facilities, which are capable of simulating the space radiation field. 相似文献
6.
本文是评论MX导弹喷管先进材料的三篇文章中的第二篇。第一篇文章于1977年4月在SAMPE季刊中发表(译文见“固体火箭技术”1978年第二期第99—105页),综述了MX导弹喷管对材料的要求,叙述了石墨材料的结构、性质和性能之间的关系。本文继续对MX的第一级和第二级发动机喷管所用先进材料进一步进行评价。 相似文献
7.
The mission's success fully depends on the Payload Operations conducted during the space flight. The Ground Team has to be trained to assist the Space Crew, to replan the cosmonaut's activities when contingengies occurr onboard and to change or cancel Payload activities when required. In order to act efficiently during the mission, the Ground Team must be prepared in advance of the flight and able to operate special tools for tracking the mission's progress, anticipating problems and taking decisions in realtime.
This document sets out the approach for conducting such a preparation for Ground Operation. It will be focused on the Altaïr mission performed in July 1993 onboard the Russian Mir space station. 相似文献
8.
This remote assistance trial, performed within the framework of the manned space flight Altaïr, was carried out by CADMOS (CNES), with the cooperation of the Sub-directorate of CNES Operational Systems, Medes, LBM of Tours and Christol Consultants. It consisted of supplying the cosmonaut performing the Orthostatism experiment (echograph acquisition) on board the Mir station with realtime assistance by an expert (LBM of Tours) working from the ground on the CADMOS premises. The various steps of the approach followed during the preparation phase are described, as well as the technical means of communication used between the Mir station and CADMOS. 相似文献
10.
新的混合键合剂系统用于端羟基聚丁二烯推进剂配方时,推进剂的高温老化特性和低温物理性质都有很大改善。混合键合剂系统由 MT_4[2.0克分子三-1-(2-甲基氮丙啶)膦化氧、0.7克分子已二酸和0.3克分子酒石酸的反应产物]、HX752[双-间苯二酰-1-(2-甲基)氨丙啶]和 BIDE(丁基亚胺二乙醇)组成,其重量百分含量分别占推进剂组成的0.10~0.20%、0.10~0.20%和0.02~0.05%。 相似文献