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101.
P.N. Bhat S.K. Gupta P.V.Ramana Murthy B.V. Sreekantan S.C. Tonwar P.R. Vishwanath 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
In a further study of sporadic emission from pulsars we find evidence for short lived intense emission from the Crab pulsar. 相似文献
102.
Dale P. Cruikshank 《Space Science Reviews》2005,116(1-2):421-439
The diverse populations of icy bodies of the outer Solar System (OSS) give critical information on the composition and structure
of the solar nebula and the early phases of planet formation. The two principal repositories of icy bodies are the Kuiper
belt or disk, and the Oort Cloud, both of which are the source regions of the comets. Nearly 1000 individual Kuiper belt objects
have been discovered; their dynamical distribution is a clue to the early outward migration and gravitational scattering power
of Neptune. Pluto is perhaps the largest Kuiper belt object. Pluto is distinguished by its large satellite, a variable atmosphere,
and a surface composed of several ices and probable organic solid materials that give it color. Triton is probably a former
member of the Kuiper belt population, suggested by its retrograde orbit as a satellite of Neptune. Like Pluto, Triton has
a variable atmosphere, compositionally diverse icy surface, and an organic atmospheric haze. Centaur objects appear to come
from the Kuiper belt and occupy temporary orbits in the planetary zone; the compositional similarity of one well studied Centaur
(5145 Pholus) to comets is notable. New discoveries continue apace, as observational surveys reveal new objects and refined
observing techniques yield more physical information about specific bodies. 相似文献
103.
Dario Lorenzetti 《Space Science Reviews》2005,119(1-4):181-199
Observations of pre-main sequence objects (T Tauri, Herbig Ae/Be and FU Orionis stars) obtained with the instrumentation on
board the Infrared Space Observatory (ISO) are reviewed. All the observations have been mainly carried out by using the two
spectrographs SWS and LWS, adopting their low resolution modes and such data have been used both for lines detection and to
reconstruct the spectral energy distributions. Line emission and photometric behaviour of pre-main sequence objects have been
analyzed in the framework of the current models, discussing the agreement (or disagreement) with them and trying to derive
the questions which should be answered by the forthcoming FIR instrumentation.
Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries:
France, Germany, The Netherlands, and the United Kingdom), and with the participation of ISAS and NASA. 相似文献
104.
Alain Abergel Laurent Verstraete Christine Joblin René Laureijs Marc-Antoine Miville-Deschênes 《Space Science Reviews》2005,119(1-4):247-271
Infrared spectroscopy and photometry with ISO covering most of the emission range of the interstellar medium has led to important
progress in the understanding of the physics and chemistry of the gas, the nature and evolution of the dust grains and also
the coupling between the gas and the grains. We review here the ISO results on the cool and low-excitation regions of the
interstellar medium, where T
gas≲ 500 K, n
H∼ 100–105 cm−3 and the electron density is a few 10−4.
JEL codes: D24, L60, 047
Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries:
France, Germany, The Netherlands, and the United Kingdom), and with the participation of ISAS and NASA. 相似文献
105.
K. Shibasaki T. Takano S. Enome H. Nakajima M. Nishio Y. Hanaoka C. Torii H. Sekiguchi T. Bushimata S. Kawashima N. Shinohara H. Koshiishi Y. Shiomi 《Space Science Reviews》1994,68(1-4):217-224
The early phases of three flares, observed by the Nobeyama Radio Heliograph, are studied. Nonthermal and thermal radio sources are identified by comparison with soft X-ray images taken by the Soft X-ray Telescope onboard the Yohkoh satellite. Two of the flares are mainly of nonthermal origin and their location coincides with one of the footpoints of soft X-ray loops. Another flare has both thermal and nonthermal components which start to brighten simultaneously. This suggests that particle acceleration and plasma compression develop simultaneously. 相似文献
106.
107.
摘 要:为探究预混气组分对不同反应路径下NOx生成影响,针对高压射流反应器,基于CFD流场特征等,构建优化了单PSR、2PSR、3PSR以及PSR+PFR四种化学反应器网络模型。在贫预混燃烧条件下,研究了纯CH4及其混合气燃烧时不同反应路径下NOx的生成情况,得出了燃烧室内不同反应区域每条反应路径NOx的生成量。结果表明,纯CH4燃烧产生的NOx主要来自于热力型、快速型和N2O-中间体型三条反应路径。绝热火焰温度的提高主要促进了热力型和N2O-中间体型NOx的生成。随着CH4或CO中加入H2摩尔分数的增加,NOx排放总量降低,快速型NOx生成速率降低,特别是火焰刷区域的。另外,混合气中CO摩尔分数的增加会导致NOx生成量增多。 相似文献
108.
109.
Knowledge of the observable properties of orbital debris is necessary to validate debris models for both the low Earth orbit (LEO) and the geosynchronous Earth orbit (GEO). Current methods determine the size and mass of orbital debris based on knowledge or assumption of the material type of the piece. Improvement in the knowledge of material is the goal of the research described herein. The process of using spectral absorption features to determine the material type is explored. A review of the optical measurements of orbital debris as well as current research in the area is discussed. Reflectances of common spacecraft materials are compared. The need for, and advances made possible by obtaining real data are explored. The prospects of the venture are investigated. 相似文献
110.
提出用一氧化二氮-乙炔火焰原子吸收光谱法测定热电池隔离粉中镁。介绍镁的最佳测定条件并具有良好线性范围的浓度,并对样品消化处理条件、干扰因素进行了综合考虑。该方法灵敏度高、重现性好,同时具有方法步骤简单、操作容易掌握等特点,达到了实验室分析质量控制的要求。 相似文献