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121.
122.
T. G. Tsuru T. Tanimori A. Bamba K. Imanishi K. Koyama H. Kubo H. Matsumoto K. Miuchi M. Nagayoshi R. Orito A. Takada S. Takagi M. Tsujimoto M. Ueno H. Tsunemi K. Hayashida E. Miyata 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(12):2688-2690
We propose a new type of wide band X-ray imaging spectrometer as a focal plane detector of the super mirror onboard on future X-ray missions including post Astro-E2. This camera is realized by the hybrid of back illumination CCDs and a back supportless CCD for 0.05–10 keV band, and a Micro Pixel Gas Chamber detecting X-rays at 10–80 keV. 相似文献
123.
R.L.C. Starling E.M. Puchnarewicz E. Romero-Colmenero K.O. Mason 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(12):2588-2593
We present a series of monitoring observations of the ultrasoft broad-line Seyfert galaxy RE J2248-511 with XMM-Newton. Previous X-ray observations showed a transition from a very soft state to a harder state five years later. We find that the ultrasoft X-ray excess has re-emerged, yet there is no change in the hard power-law. Reflection models with a reflection fraction of 15, and Comptonisation models with two components of different temperatures and optical depths (kT1 = 83 keV, T1 = 30 eV, τ1 = 0.8; KT2 = 3.5 keV, T2 = 60 eV, τ2 = 2.8) can be fit to the spectrum, but cannot be constrained. The best representation of the spectrum is a model consisting of two blackbodies (kT1 = 0.09 ± 0.01 keV, kT2 = 0.21 ± 0.03 keV) plus a power-law (Γ = 1.8 ± 0.08). We also present simultaneous optical and infrared data showing that the optical spectral slope also changes dramatically on timescales of years. If the optical to X-ray flux comes primarily from a Comptonised accretion disk we obtain estimates for the black hole mass , accretion rate and inclination cos(i) 0.8 of the disk. 相似文献
124.
M. Nakajima T. Mihara K. Makishima H. Niko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2756-2758
We report on the luminosity dependent change of the cyclotron resonance energy obtained from a transient X-ray pulsar, 4U 0115+63. Using RXTE data observed on 1999 March, we found that the fundamental resonance energy stayed constant (11 keV) when the source luminosity was above 5 × 1037 erg s−1. As the luminosity decreased below 5 × 1037 erg s−1, the fundamental resonance energy gradually increased up to 16 keV at 0.16 × 1037 erg s−1. The luminosity dependence of the resonance energy can be understood by the change of the accretion column height. 相似文献
125.
F. Frontera D. Dal Fiume W. Dusi E. Morelli G. Spada G. Ventura 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
The transient X-ray pulsar A0535+26 was observed on October 4, 1980 during a high level intensity outburst with a balloon borne hard X-ray detector. High statistical quality source spectra were determined up to 100 keV. Both blackbody and Wien laws fit well the data. Pulse phase spectroscopy shows variation of temperature index between 7.5 and 8.5 keV in the off source spectra and between 7.4 and 10.5 keV in the off pulse spectra. The time averaged luminosity above 30 keV is 8×1036 erg/s. 相似文献
126.
The X-ray Nova GRO J0422+32 in its low brightness has been identified with a B 21
m
, R20
m
star on Palomar Sky Survey glass copies. The scans obtained with an automatical microdensitometer along with our special PC program were used. The resulting outburst amplitude 8
m
is one of similarity features for the class of the low mass X-ray Novae, black hole candidates. 相似文献
127.
康普顿散射对X射线热激波破坏效应的影响 总被引:1,自引:0,他引:1
本文应用GRAY三相物态方程及Lagrange数值模拟方法,计算并讨论了康普顿散射对X射线热激波及其破坏效应的影响。计算结果表明,对较硬的X射线谱(15keVPlanck谱),康普顿散造成量沉积与热击波峰压明显下降,在LY-12铝中,能量沉积的相对差△E(x)/E(x)可达9%-22%,热击波峰压的相对差△pm(x)/pm(x)约为12%。 相似文献
128.
P.L. Bernacca 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
The eccentric binary model for X Persei is discussed with a view to most recent determination of mass, radius and mass loss rate. The existence of such a system depends critically on the value of viscosity in the outer layers of the star and, in the case where viscosity is induced by shear turbolence, on the axial rotational velocity. The parameters of the binary system are derived in the most favourable case. 相似文献
129.
Lara Sidoli 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
In the recent years, the discovery of a new class of Galactic transients with fast and bright flaring X-ray activity, the supergiant fast X-ray transients, has completely changed our view and comprehension of massive X-ray binaries. These objects display X-ray outbursts which are difficult to be explained in the framework of standard theories for the accretion of matter onto compact objects, and could represent a dominant population of X-ray binaries. I will review their main observational properties (neutron star magnetic field, orbital and spin period, long term behavior, duty cycle, quiescence and outburst emission), which pose serious problems to the main mechanisms recently proposed to explain their X-ray behavior. I will discuss both present results and future perspectives with the next generation of X-ray telescopes. 相似文献
130.
W.Q. Gan Y.P. Li L.I. Miroshnichenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(6):908-913
The footpoint motions of flare hard X-ray (HXR) sources are directly related to the reconnection scenario of a solar flare. In this work, we tried to extract the information of footpoint motions for a number of flares observed with RHESSI. We found that the RHESSI flare results of the footpoint motions strongly support the classification proposed from the observations of YOHKOH/HXT. Furthermore, it is found that a flare can consist of two types of footpoint motions. We discussed the connections of the footpoint motions with the two-dimensional reconnection models. 相似文献