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151.
Pietro Ubertini A. Corsi S. Foley S. McGlynn G. De Cesare A. Bazzano 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
After more than six and half years in orbit, the ESA space observatory INTEGRAL has provided new, exciting results in the soft gamma-ray energy range (from a few keV to a few MeV). With the discovery of about 700 hard X-Ray sources, it has changed our previous view of a sky composed of peculiar and “monster” sources. The new high energy sky is in fact full of a large variety of normal, very energetic emitters, characterized by new accretion and acceleration processes (see also IBIS cat4 (Bird et al., 2010). At the same time, about one GRB/month is detected and imaged by the two main gamma-ray instruments on board: IBIS and SPI. In this paper, we review the major achievements of the INTEGRAL observatory in the field of Gamma-Ray Bursts. We summarize the global properties of Gamma-Ray Bursts detected by INTEGRAL, with respect to their duration, spectral index, and peak flux distributions. We recall INTEGRAL results on the spectral lag analysis, showing how long-lag GRBs appear to form a separate population at low peak fluxes. We review the outcome of polarisation studies performed by using INTEGRAL data. Finally, concerning single GRB studies, we highlight the properties of particularly interesting Gamma-Ray Bursts in the INTEGRAL sample. 相似文献
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气象卫星扫描辐射计的辐射定标 总被引:2,自引:0,他引:2
朱广赜 《中国空间科学技术》1992,12(5):27-33
阐述了气象卫星扫描辐射计的辐射定标。包括卫星发射前的地面定标,飞行中的星上定标及星地对比定标。指出飞行中的可见光波段的定标至今还未能投入业务使用,仍处于研究阶段,而静止气象卫星的飞行中定标,无论红外或是可见光波段只能做到相对定标。为解决绝对定标问题,必须寻求星体外的客观目标作为定标源。采用这一途径,即使星上定标设备失效,也不致影响卫星数据的使用。 相似文献
155.
6mm,8mm,13mm辐射计校准系统的研制 总被引:3,自引:0,他引:3
为解决相应频段的辐射计的灵敏度、线性度、稳定性的定标问题.叙述了6mm,8mm,13mm辐射计校准系统的主要技术问题,给出了技术指标,系统组成,工作原理,校准结果及不确定度分析.该系统在国内首次将变温标准辐射源用于辐射计校准,有广泛的应用前景. 相似文献
156.
介绍了适用于红外焦平面成像探测辐射特性测量的3种典型标定方案,推导了3种方案对应的单像元辐射通量公式,并在此基础上分析了3种方案对黑体温度的需求。对3种方案的优缺点进行了综合比较,对特殊应用场合的标定方案提出了建议。 相似文献
157.
本文提出一种基于混响室平台将电磁环境和自然环境结合的综合试验箱集成技术,该试验箱集成了环境试验条件和电磁辐射敏感度试验条件,可以在高低温、湿热、温度循环、温度冲击等多种环境条件下同时对电子设备施加电磁辐射干扰,考核电子设备在同施加环境应力和电磁应力的复杂条件下的适应性。经过设计、建造和测试,该集成技术满足各项预期指标并容易进行推广,可进一步降低设备试验成本。 相似文献
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The aim of the present paper is to study the numerical solutions of the steady MHD two dimensional stagnation point flow of an incompressible nano fluid towards a stretching cylinder.The effects of radiation and convective boundary condition are also taken into account.The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis.The resulting nonlinear momentum,energy and nano particle equations are simplifed using similarity transformations.Numerical solutions have been obtained for the velocity,temperature and nanoparticle fraction profles.The influence of physical parameters on the velocity,temperature,nanoparticle fraction,rates of heat transfer and nanoparticle fraction are shown graphically. 相似文献
160.
A.R. Kennedy X.S. Wan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Radiation exposure in space is expected to increase the risk of cancer and other adverse biological effects in astronauts. The types of space radiation of particular concern for astronaut health are protons and heavy ions known as high atomic number and high energy (HZE) particles. Recent studies have indicated that carcinogenesis induced by protons and HZE particles may be modifiable. We have been evaluating the effects of proton and HZE particle radiation in cultured human cells and animals for nearly a decade. Our results indicate that exposure to proton and HZE particle radiation increases oxidative stress, cytotoxicity, cataract development and malignant transformation in in vivo and/or in vitro experimental systems. We have also shown that these adverse biological effects can be prevented, at least partially, by treatment with antioxidants and some dietary supplements that are readily available and have favorable safety profiles. Some of the antioxidants and dietary supplements are effective in preventing radiation induced malignant transformation in vitro even when applied several days after the radiation exposure. Our recent progress is reviewed and discussed in the context of the relevant literature. 相似文献