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爆炸螺栓分离装置是一种应用广泛且相对成熟的点式火工分离装置,在航天器分离中应用广泛。爆炸螺栓通过腔内炸药爆炸的拉伸、剪切力学效应,使螺栓特定部位断裂实现解锁。爆炸分离过程会产生时间短、频率高、峰值高的冲击波,对航天器结构产生冲击。分离过程中,爆炸螺栓断裂位置尺寸、炸药药量和螺栓预紧力等因素的偏差都会影响爆炸分离产生的冲击响应。通过不同设计尺寸偏差下的有限元分析计算,研究了不同因素对航天器关键位置冲击响应谱的影响。结果表明爆炸螺栓断裂位置的端面尺寸和炸药药量的变化对冲击响应谱有着显著影响。 相似文献
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航天火工装置点火输出及传递的可靠性一般按GJB1307A-2004《航天火工装置通用规范》进行裕度试验,如120%、75%输出能量等。实际验证中,常采用120%装药量、75%装药量进行考核,忽视了点火输出压力散差造成的影响,可能导致该考核失效。文章从点火输出及传递压力一致性的角度,对其关键影响因素进行分析:针对点火输出环节,采用粒度更细的Al/KClO4烟火药改善燃烧性能和增加挡药板约束的方法,成功提高了点火的输出一致性;针对燃烧传递环节,采用更换黑火药粒为药饼和更换赛璐璐为铝箔增加约束的方法,成功提高了燃烧传递的输出一致性。两种方法成功提高了航天火工装置点火输出及传递的精细化控制水平,可有效降低裕度考核失效的可能,保证裕度试验结果的可靠性。 相似文献
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在1996年6月第27届ICT国际年度会议,俄罗斯门捷列夫化工学院BorisN.Kondrlkov报导了他们防止含能材料意外爆炸方法的研究工作,文章中说,过去十年中,俄国门捷列夫化工学院实验室进行了旨在防止合能材料发生意外爆炸的方法的系统研究工作,专门提出了预防计划和实施这些工作的规则,总体途径包括:①对材料生产和(或)应用技术作仔细分析;对于发生意外爆炸的起因和后果进行检查,对加工过程中最危险的阶段进行隔离.②对造成热释放的化学反应进行热力学和动力学研究,同时进行物理、机械和流体动力学过程研究。如果可能,建立热释放… 相似文献
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圆轨道卫星偏心率的一阶偏导数在入轨点不存在,因此,给我们沿用以往的线性偏导数制导理论造成了困难。经过研究简捷地找到了圆轨道卫星偏心率偏差的毕达哥拉斯公式,解决了发射圆轨道卫星制导问题,并给出了通过调整发动机关机时间和末级飞行程序来达到设计时需要的圆轨道的标准指标公式。 相似文献
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几种化合物在改性双基推进剂中降低燃速的作用 总被引:2,自引:0,他引:2
本文介绍了六种化合物在改性双基推进剂中的降燃速作用,这些化合物是黑索今(RDX)、奥克托金(HMX)、1,3,5-三氨基2,4,6-三硝基苯(TATB)、硝酸铵、蔗糖入醋酸酯(SOA)、草酸铵。讨论了它们对燃气发生剂降低燃速的贡献和机理,从实验数据的分析中得出了几点有用的结论。 相似文献
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Condensation reactions and formation of amides, esters, and nitriles under hydrothermal conditions 总被引:2,自引:0,他引:2
Hydrothermal pyrolysis experiments were performed to assess condensation (dehydration) reactions to amide, ester, and nitrile functionalities from lipid precursors. Beside product formation, organic compound alteration and stability were also evaluated. Mixtures of nonadecanoic acid, hexadecanedioic acid, or hexadecanamide with water, ammonium bicarbonate, and oxalic acid were heated at 300 degrees C for 72 h. In addition, mixtures of ammonium bicarbonate and oxalic acid solutions were used to test the abiotic formation of organic nitrogen compounds at the same temperature. The resulting products were condensation compounds such as amides, nitriles, and minor quantities of N-methylalkyl amides, alkanols, and esters. Mixtures of alkyl amide in water or oxalic acid yielded mainly hydrolysis and dehydration products, and with ammonium bicarbonate and oxalic acid the yield of condensation products was enhanced. The synthesis experiments with oxalic acid and ammonium bicarbonate solutions yielded homologous series of alkyl amides, alkyl amines, alkanes, and alkanoic acids, all with no carbon number predominances. These organic nitrogen compounds are stable and survive under the elevated temperatures of hydrothermal fluids. 相似文献
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Nechaev AP Myasnikov VI Stepanova SI Kozerenko OP Isaev GF Bronnikov SV 《Acta Astronautica》1998,42(1-8):331-338
The methodological approach to the study of cosmonauts errors is discussed in the paper. Within its framework an error is considered in psychophysiological aspect as consequence of cosmonaut "psychophysiological troubles" caused by combined effect of flight extreme conditions on his/her organism. This approach was used for the investigation of interrelation between cosmonauts errors, their psychophysiological state and work-rest schedule peculiarities. It includes procedures of expert analysis of data received in the course of radio and TV sessions with crew, analysis of timelines as well deviations in "crew-spacecraft" system functioning. These data are accumulated, systematized and processed in data base. Realization of the suggested approach does not require specialized onboard equipment and crew members time expenditure. Some results of inflight data analysis are presented to illustrate its potentials. 相似文献
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二硝酰胺铵(ADN)球形化工艺研究 总被引:4,自引:1,他引:4
介绍了近年来国外关于二硝酰胺铵(ADN)球形化的工艺方法,重点讨论了中间介质、分散剂、表面活性剂和热稳定剂的作用及其选择方法。 相似文献
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高能氧化剂二硝酰胺铵研究进展 总被引:1,自引:0,他引:1
介绍了高能氧化荆二硝酰胺铵(ADN)的特性和应用前景,以及国内外在ADN合成方法、热稳定性、成球造粒、防吸湿性、燃烧性能与应用研究方面所取得的进展。有关资料表明,各国的研究都还处在合成及性能改善阶段,尤其在防吸湿方面尚未取得突破,因而作为一种性能优越的固体推进荆氧化荆,ADN还没有在型号中得到普遍应用。 相似文献
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We have investigated an enzymatic racemization reaction as a marker for extraterrestrial life, which resulted in a change in optical rotation of a mandelic acid over time, as measured by polarimetry. Mandelate racemase was active in aqueous buffer in a temperature range between 0 degrees C and 70 degrees C and also in concentrated ammonium salt solutions and water-in-oil microemulsions in a temperature range between -30 degrees C and 60-70 degrees C; however, the enzyme was not active in several organic cryosolvents. Thus, we have demonstrated that concentrated ammonium salt solutions and water-in-oil microemulsions, both of which are able to form on extraterrestrial planets and moons in the presence of liquid water, are suitable media for enzyme reactions at subzero temperatures. Kinetic data for the mandelate racemase reaction obtained by polarimetry, while reproducible and internally consistent, differed significantly from several sets of data obtained previously by other methods such as chromatography and hydrogen-deuterium exchange. However, we conclude that reactions yielding a polarimetric signal, such as the racemizations employed in this work, are suitable mechanisms by which to utilize a change in chirality over time as a tool to detect signs of life. 相似文献