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1.
A scanning infrared radiometer used to measure nitric acid was flown on the STRATOPROBE Flight of November 8, 1978. Using the observed thermal emission from 6.5 to 7.4 microns during the balloon ascent, a water vapour profile has been derived using a band model of the water vapour lines in this spectral region. The resulting profile has a minimum of 3.3 ppmv at the tropopause and then rises to a value of 5 ppmv by 30 km. The profile is comparable to the profile from another water vapour instrument from the National Physical Laboratory which was flown on the LIP balloon payload on the same day. A coincident profile from the LIMS experiment on NIMBUS 7 was also obtained since the STRATOPROBE experiment was flown as a correlative measurement for the LIMS experiment.  相似文献   

2.
A simple gamma ray telescope based on a time of flight triggering device has been constructed to measure medium energy photons (4–50 MeV). This instrument has been flown twice aboard stratospheric balloons. The results of these flights, used to separate the cosmic diffuse gamma-radiation from the atmospheric flux, using the growth curves, are presented.  相似文献   

3.
4.
A new instrument which can rapidly measure plasma particle distribution functions has been developed based upon recent innovations in electrostatic analyzer design and position sensitive particle detection. The new analyzer uses a quadrispherical geometry, but has a completely uniform 360° fan-shaped field of view. The polar angular distribution of entering particles is spatially imaged onto a position sensitive detector at the annular exit aperture after a deflection through 90°. Several methods of position sensitive detection have been successfully used in conjunction with this analyzer. The simplest is individual channel multipliers spaced around the annular exit. Microchannel plate electron multipliers permit greater position resolution to be obtained, and a detector using microchannel plates followed by a resistive anode image converter obtains angular resolution of about one degree -- i.e., 360 individual angle pixels. Instruments of this type were flown on a sounding rocket in early 1982 and will be included on the Giotto comet mission and the AMPTE ion release module (IRM).  相似文献   

5.
航天飞行器需要满足长时间待机、长轨迹飞行及高准确入轨的要求。新一代运载火箭从单一的惯性平台导航方式,改进为多套捷联惯组冗余制导方式。火箭飞行时,其中一套惯组作为主份,控制火箭飞行,其它惯组则处于热备份状态,参与冗余判断,并在主份出现故障时接管其工作。这就要求在火箭飞行前,需对冗余惯组之间的初始角度差进行现场标定。提出了利用光电测角技术原理,对冗余惯组之间的初始安装相对角度差进行测量,论述了标定方法及测量设备的研制方案,并对测量结果进行解算和原理验证,试验表明其具有测量原理正确、测试结果准确以及可操作性强等优点。  相似文献   

6.
将我国所产卤虫(Artemia salina)的卵,由1987年8月5日发射的返地卫星搭载,在空间飞行5天。于飞行完成后第8、21、24、34及66天,随机取卵进行人工孵化及发育观察。见到的主要现象有:(1)飞行卵的早期发育进程显著变慢;(2)随着回收后时间的延长,飞行卵的早期发育速度出现回升的趋势;(3)飞行卵早期发育中的冒出率和孵出率一般都比地面对照组的低,且随着回收后时间的延长,有继续下降的趋势;(4)飞行卵孵出的卤虫,自孵出第1天至接近全部自然死亡的23天内,存活率的下降情况与地面对照组的没有差异。本文提出一种空间飞行因素对卤虫卵损伤的“临界程度”的假设。实验还表明,我国所产的卤虫卵对空间飞行因素的作用是敏感的,是一种空间生物学研究的好材料。   相似文献   

7.
The Polar Balloon Atmospheric Composition Experiment (P-BACE) is a new generation of neutral gas mass spectrometer based on the time-of-flight principle. P-BACE is the scientific experiment on the Mars Environment Analog Platform (MEAP) flown successfully on a balloon mission in summer 2008. The MEAP mission was flown with a 334,000 m3 helium balloon in the stratosphere on a semicircular trajectory from northern Sweden around the North Pole to Canada using the summer northern hemispheric wind current. The atmospheric conditions at an atmospheric altitude of 35–40 km are remarkably similar to those on the surface of Mars and thus the balloon mission was an ideal testbed for our mass spectrometer P-BACE. Originally this instrument was designed for in situ measurements of the chemical composition of the Martian atmosphere.P-BACE has a unique mass range from 0 to 1000 amu/q with a mass resolution mm (FWHM) > 1000, and the dynamic range is at least six orders of magnitude. During this experiment, the acquisition of one mass spectrum is a sum of 65,535 single spectra, recorded in a time frame of 66 s.The balloon mission lasted 5 days and had successfully demonstrated the functionality of the P-BACE instrument during flight conditions. We had recorded more than 4500 mass spectra. With little modifications, P-BACE can be used on a planetary mission for Mars, but for example also for Venus or Mercury, if placed on a satellite.  相似文献   

8.
Three arthropod systems are discussed in relation to their complementary and potential use in Space Biology. In a next biosatellite flight, Drosophila melanogaster pre-adapted during several months to different g levels will be flown in an automatic device that separates parental from first and second generations. In the same flight, flies will be exposed to microgravity conditions in an automatic unit in which fly motility can be recorded. In the International Microgravity Laboratory-2, several groups of Drosophila embryos will be grown in Space and the motility of a male fly population will be video-recorded. In the Biopan, an ESA exobiology facility that can be flown attached to the exterior of a Russian biosatellite, Artemia dormant gastrulae will be exposed to the space environment in the exterior of the satellite under a normal atmosphere or in the void. Gastrulae will be separated in hit and non-hit populations. The developmental and aging response of these animals will be studied upon recovery. With these experiments we will be able to establish whether exposure to the space environment influences arthropod development and aging, and elaborate on some of the cellular mechanisms involved which should be tested in future experiments.  相似文献   

9.
Absolute solar UV spectra were obtained with a 14m spectrometer on a balloon flight from Palestine, Texas on September 23, 1981. This balloon reached a float altitude of 39 km at solar noon. The ozone density profiles derived from these spectra are discussed. The measurements are compared with data obtained from the same calibrated instrument flown in 1976 at solar minimum.  相似文献   

10.
An algorithm has been developed that retrieves water vapour profiles in the upper troposphere and lower stratosphere from optical depth spectra obtained by the Measurements of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation (MAESTRO) instrument onboard the SCISAT satellite as part of the Atmospheric Chemistry Experiment (ACE) mission. The retrieval relies on ro-vibrational absorption of solar radiation by water vapour in the 926–970 nm range. During the iterative inversion process, the optical depth spectra are simulated at the spectral resolution and sampling frequency of MAESTRO using the correlated-k approximation. The Chahine inversion updates the water vapour volume mixing ratio (VMR), adjusting all retrieval layers simultaneously, to match the observed differential optical depth due to absorption by water vapour and ozone at each tangent height. This approach accounts for significant line saturation effects. Profiles are typically obtained from ∼22 km down to the cloud tops or to 5 km, with relative precision as small as 3% in the troposphere. In the lower stratosphere, the precision on water vapour VMR is ∼1.3 μmol/mol in an individual retrieval layer (∼1 km thick). The spectral capability of MAESTRO allows for the clear separation of extinction due to water vapour and aerosol, and for the fitting quality to be quantified and used to determine an altitude-dependent convergence criterion for the retrieval. In the middle troposphere, interhemispheric differences in water vapour VMR are driven by oceanic evaporation whereas in the upper troposphere, deep convection dominates and a strong seasonal cycle is observed at high latitudes.  相似文献   

11.
研究火箭空中爆炸冲击波参数预测方法对于乘员舱的安全评估具有重要意义。为了探究火箭空中爆炸时飞行高度对峰值超压的影响,获取冲击波参数快速预测方法,利用ANSYS/LS-DYNA有限元软件对火箭飞行至0~20 km高度爆炸进行了有限元仿真分析。结果表明,作用于乘员舱的冲击波峰值超压随飞行高度的增加而快速减小。火箭空中爆炸冲击波压强衰减系数与飞行高度之间的关系服从二次函数衰减。在此基础上,提出了考虑高度效应的火箭空中爆炸冲击波峰值超压预测公式,可为乘员舱的快速危害性评估以及防护研究提供一定参考。   相似文献   

12.
A rocket borne payload for simultaneous measurement of the electric field along and perpendicular to the rocket spin axis and the electron density in the medium was developed and flown from Thumba (8° 31′N, 0° 47′S dip) onboard two Centaure rockets for the study of plasma dynamcis in the equatorial E-region. The arrangement of sensors in this payload allows near continuous measurements of some of these parameters to be made.  相似文献   

13.
Space flight experiments on Chinese silkworm (Bombyx mori L.) were conducted on board the Russian 10th Biosatellite for 12 days. The samples included silkworm eggs, larvae, cocoons, pupae and moths. The processes of spinning, cocooning, mating, oviposition, larval hatching, pupation and moth emergence all completed well in space. The following effects of space flight on silkworm development were observed: The times of hatching and oviposition in the flight group were 2 to 3 days earlier than in the control group; the hatching rate of diapause eggs during space flight seemed higher than that of the control group; the life span of 2 of the 7 varieties flown was shortened; genetical variations appeared in 3 varieties. The results showed that the embryonic stage was probably the period most sensitive to the space flight environment.  相似文献   

14.
翼身融合(BWB)飞行器满足未来民用航空经济、绿色、低碳的运行需求,是重要的发展方向。针对BWB飞行器的飞行控制系统,对其安全性与系统设计进行了研究。给出基于系统理论的事故模型及过程,与相应的安全性分析,重点对BWB飞行器飞行控制系统内的复杂逻辑关系、不安全控制动作、危害致因进行分析;进行切换系统设计,给出低可靠先进系统和高可靠备用系统的设计过程,并分析切换逻辑;基于设计进行仿真验证。研究结果表明:系统理论过程分析方法能够支持BWB飞行器飞行控制系统复杂逻辑关系的安全隐患分析,同时所设计的飞行控制系统具有一定的安全性与实用性。  相似文献   

15.
推进剂利用系统连续液位测量滤波算法研究   总被引:1,自引:0,他引:1  
针对我国低温推进剂利用系统中连续液位测量中的错节问题,提出了一种基于流量的液位测量滤波算法。介绍了该算法的基本原理,对算法进行了数学建模与数字仿真。通过对仿真结果的分析证实了该算法可以有效解决火箭飞行过程中由于液位晃动造成的测量误差问题,具有一定的工程应用价值。  相似文献   

16.
针对特定探测天体,给出了特殊用途的探空火箭与其实现空间交会的时刻与地点的计算方法.根据特定天体的运行轨道,发射前算出标称交会飞行轨道,装订在箭载计算机内.火箭发射后,利用箭载惯性导航系统确定自身当前的位置与速度,比对标称飞行轨道参数得出飞行偏差,通过控制火箭推力偏斜调整飞行轨道,使探空火箭在交会时刻到达交会点,并在交会时刻相对与惯性空间的速度为0.定义了研究所用的各种坐标系,建立了火箭飞行动力学方程.研究了标称飞行轨道最优交会点选取,交会时间与发射时间计算等问题.给出了发射后动力飞行段的制导控制规律,核心思想是将控制信号分解为时间控制、当地水平面上的海拔高度控制、南北控制与东西控制,通过设置偏置量减小关机后轨道摄动因素引起的漂移.利用计算机数值仿真验证了这种制导控制规律的可行性.  相似文献   

17.
根据子午工程探空火箭电子和电场探测需求,设计了套筒式伸杆展开机构.通过电子伸杆和电场伸杆的结构方案设计、力学仿真分析,伸杆单项力学试验,伸杆与整箭的匹配力学试验以及伸杆飞行试验验证得出,该伸杆技术方案合理可行,伸杆总体构型、布局设计及结构方案设计满足科学探测各项技术指标的要求.   相似文献   

18.
Animal models have been used to determine the effects of spaceflight on the immune system. Rats and rhesus monkeys have been the primary animals used for actual space flight studies, but mice have also been utilized for studies in ground-based models. The primary ground based model used has been hindlimb unloading of rodents, which is similar to the chronic bed-rest model for humans. A variety of immune responses have been shown to be modified when animals are hindlimb unloaded. These results parallel those observed when animals are flown in space. In general, immune responses are depressed in animals maintained in the hindlimb unloading model or flown in space. These results raise the possibility that spaceflight could result in decreased resistance to infection in animals.  相似文献   

19.
The Ballooncraft Support Systems were developed by NASA Wallops Flight Facility for use on ULDB class balloon missions. The support systems have now flown two missions supporting the Cosmic Rays Energetics and Mass (CREAM) experiment. The first, CREAM I, flown in December 2004, was for a record breaking 41 days, 21 h, and the second flight flown in December 2005, was for 28 days, 9 h. These support systems provide CREAM with power, telecommunications, command, and data handling including flight computers, mechanical structures, thermal management, and attitude control to help ensure a successful scientific mission. This paper addresses the performance and success of these support systems over the two missions.  相似文献   

20.
Pre-mated adult female newts and fertilized eggs will be flown on the International Microgravity Laboratory-2 flight, in 1994. One objective of the flight will be to observe the influence of microgravity on the development of the gravity-sensing organs in the inner ear. These organs contain sensory hair cells covered by a layer of dense stones (otoconia). Gravity and linear acceleration exert forces on these masses, leading to excitation of the nerve fibers innervating the hair cells. If the production of the otoliths is regulated to reach an optimal weight, their development might be abnormal in microgravity. Ground-based control experiments are reported describing the developmental sequence in which both the otoliths and their associated sensory epithelium and the semicircular canals appear and develop. Three-dimensional reconstruction of serial sections through the otic vesicle of newt embryos at stages 31 through 58 demonstrate the first appearance, relative position and growth of the otoliths. Reports of experiments in which fertilized frog eggs were flown on a Russian Cosmos mission conclude that the utricular otolith is increased in volume, whereas the saccular otolith maintains normal size, suggesting that at least in the utricle, the weight of the otolith might be regulated.  相似文献   

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