MX导弹第二级发动机

引言MX导弹第二级发动机用来提供飞行第二阶段的动力,以及飞行第一阶段和第二阶段的滚转控制力矩。MX导弹第二级发动机的直径为92英寸(2337毫米),长220.4英寸(5598毫米),毛重60234磅(27322公斤),其基本结构如图1所示。经过16个月的系统论证(SD)和头4个月的全尺寸工程研制(FSED),第二级发动机业已进行了优化,以便满足系统要     

合成孔径快速数字算法

本文描述了合成孔长雷达数字信号处理的准最佳算法，对该算法的计算复杂性及其与最佳处理相比之下的不足进行了评估，分析了合成孔径方向图的形式，提出了选择算法参数的建议。     

Analytical definition and proposed concept for the manned infrastructure of a lunar outpost

A recent study made by ESA has reviewed the scientific investigations to be only, or best, performed on the Moon (Return to the Moon, ESA SP-1150, June 1992), and has identified the need for a manned lunar outpost to provide support to field geologists in sampling and in-situ observations of the lunar surface, and to allow the refurbishments of surface stations and rovers. Planning and development for a manned outpost on the Moon requires an in-depth understanding and analysis of the functions this outpost is expected to perform. We therefore analyzed the impact of the proposed scientific investigations on the design of a manned lunar outpost. The specific questions raised in our study were: What are the medical, physiological and psychological risks for a crew to stay and to work on the Moon? What transit and lunar surface infrastructures (habitats and vehicles) are needed to minimize those risks?     

美国固体推进剂的检验与鉴定规程

美国建立了测定固体推进剂的化学、物理和界面等各项性能的标准检验规程。对推进剂来说,所产生的整套数据,必须是充分的,而且足以确保其安全、工艺参数,并满足质量鉴定指标。固体推进剂的安全、化学、物理、力学等各项性能的检验,是与特定的发动机指标相联系的。测试项目的选择取决于推进剂的类型(如单基或双基,复合或复合改性双基),发动机使用条件(如密闭或不密闭的发动机壳体、相对应的溫度及高度的点火条件),以及要求的贮存寿命。目前,美国对推进剂的检验和鉴定大约进行六十种测试。本文提出了检验与鉴定准则的概要,讨论了各项或各类测试的细节与目的。     

The dynamics of blood biochemical parameters in cosmonauts during long-term space flights

Most of the previously obtained data on cosmonauts' metabolic state concerned certain stages of the postflight period. In this connection, all conclusions, as to metabolism peculiarities during the space flight, were to a large extent probabilistic. The purpose of this work was study of metabolism characteristics in cosmonauts directly during long-term space flights. In the capillary blood samples taken from a finger, by "Reflotron IV" biochemical analyzer, "Boehringer Mannheim" GmbH, Germany, adapted to weightlessness environments, the activity of GOT, GPT, CK, gamma-GT, total and pancreatic amylase, as well as concentration of hemoglobin, glucose, total bilirubin, uric acid, urea, creatinine, total, HDL- and LDL cholesterol, triglycerides had been determined. HDL/LDL-cholesterol ratio also was computed. The crewmembers of 6 main missions to the "Mir" orbital station, a total of 17 cosmonauts, were examined. Biochemical tests were carried out 30-60 days before launch, and in the flights different stages between the 25-th and the 423-rd days of flights. In cosmonauts during space flight had been found tendency to increase, in compare with basal level, GOT, GPT, total amylase activity, glucose and total cholesterol concentration, and tendency to decrease of CK activity, hemoglobin, HDL-cholesterol concentration, and HDL/LDL - cholesterol ratio. Some definite trends in variations of other determined biochemical parameters had not been found. The same trends of mentioned biochemical parameters alterations observed in majority of tested cosmonauts, allows to suppose existence of connection between noted metabolic alterations with influence of space flight conditions upon cosmonaut's body. Variations of other studied blood biochemical parameters depends on, probably, pure individual causes.     

Results of space experiment program "Interferon"

The results of the biological space experiment "Interferon" performed by two international cosmonaut teams (26 May 1980, and 16 May 1981) aboard space laboratory Solyut-6 are reported: (1) Human lymphocytes separated from blood of healthy donors and placed into "Interferon I" equipment could be kept for 7 days in suspension culture under spaceflight conditions. Interferon production could be induced in human lymphocytes by preparations of different origin: virus, synthetic polyribonucleotides, bacterial protein and plant pigment. An increased lymphocyte interferon production in space laboratory compared to ground control was observed. (2) Human interferon preparations and interferon inducers placed in space laboratory at room temperature for 7 days maintained their biological activity. (3) A decrease of induced interferon production and natural killer activity of lymphocytes isolated from peripheral blood of cosmonauts was observed on the 1st day on Earth after 7-days spaceflight.     

Human exploration of Mars

The human exploration of Mars has the potential to return a rich harvest of scientific information about that planet, its possible past biological history and the prospects for future habitation by Earthly life. The realization of that potential will require new approaches and new technologies--a whole new paradigm in space exploration. Picture yourself exploring the surface of Mars, where your task involves conducting a detailed investigation of features larger than the United States in order to uncover a record of planetary history spanning over four billion years.     

玻璃基环形振动微陀螺谐振子的设计与制造工艺

针对传统单晶硅材料热胀系数不稳定引起的硅基环形振动微陀螺的温度漂移问题,开展了玻璃基环形振动微陀螺谐振子的设计,并提出了一种新型的玻璃基准三维微结构制造工艺,借助微型电子机械系统（MEMS）工艺中成熟的深硅刻蚀、阳极键合、化学机械抛光等通用加工技术,融合玻璃熔融工艺,解决了玻璃基准三维微结构的制造工艺难题,同时保证了高的加工精度,实现了玻璃基环形振动微陀螺谐振子的高精度批量制造。     

用于石英谐振器研究的频域反射计

本文介绍一种用于精确测量石英晶体谐振频率特性的调相频域反射计系统的概念和工作原理。反射计法容许被测晶体谐振器远置于一环境试验箱中;这系统还能同时而又单独地对任一给定晶体中发生的不同谐振模(例如,SC切晶体中的b模和c模谐振)进行频率测量。这一反射计技木主要适用于对谐振器进行以下基本研究:频率一温度特性的研究;滞后现象和热冲击效应的研究;幅度一频率因数和多模激励特性的研究以及核幅射效应的研究,等等。本仪器也可应用于晶体生产过程,包括自动化生产、测试以及质量控制等。