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61.
T. Saito T. Nakano H. Hoshizuki K. Sakai Y. Tatematsu S. Mitsudo I. Ogawa T. Idehara V. E. Zapevalov 《International Journal of Infrared and Millimeter Waves》2007,28(12):1063-1078
A 300 GHz CW gyrotron FU CW I has been developed and installed in the Research Center for Development of Far-Infrared Region,
University of Fukui as a power source of a high frequency material processing system. Its performance was tested and the maximum
power of 1.75 kW / CW has been attained at the beam voltage of 15 kV and the beam current of 1A. The maximum window power
efficiency of 15.5% has been obtained at the cathode voltage slightly lower than 15 kV. This gyrotron is designed to deliver
a Gaussian beam after mode conversion from the oscillation mode TE22,8 in the cavity with a complex of an internal radiator and beam shaping mirrors. The detailed measurement with an infrared
camera has confirmed that a Gaussian beam is radiated when the magnetic field strength B
c
at the cavity is adjusted at a proper value. However, within a range of B
c
, the output power is emerged into multiple directions, which suggests simultaneous oscillation of competing cavity modes. 相似文献
62.
Souza Filho AG Kobayashi N Jiang J Grüneis A Saito R Cronin SB Mendes Filho J Samsonidze GG Dresselhaus G Dresselhaus MS 《Physical review letters》2005,95(21):217403
In this Letter, we report the effects of strain on the electronic properties of single-wall carbon nanotubes. When we normalize the electronic transition energies to the corresponding values obtained for unstrained tubes, we obtain that, regardless of the tube diameter, all the data collapse onto universal curves following an n - m = constant family pattern. In the case of metallic tubes, quantum interference effects on the Raman cross section are predicted for strained tubes when the energies of the lower and the upper components have nearly the same values. Experimental evidence for the strain-induced Raman cross section changes is observed in single nanotube spectroscopy. 相似文献
63.
64.
Akchurin N Langland J Onel Y Bonner BE Corcoran MD Cranshaw J Nessi-Tedaldi F Nessi M Nguyen C Roberts JB Skeens J White JL Bravar A Giacomich R Penzo A Schiavon P Zanetti A Bystricky J Lehar F de Lesquen A van Rossum L Cossairt JD Read AL Derevschikov AA Matulenko YA Meschanin AP Nurushev SB Patalakha DI Rykov VL Solovyanov VL Vasiliev AN Grosnick DP Hill DA Laghai M Lopiano D Ohashi Y Shima T Spinka H Stanek RW Underwood DG Yokosawa A Funahashi H Goto Y Imai K Itow Y Makino S Masaike A 《Physical review D: Particles and fields》1993,48(7):3026-3036
65.
66.
67.
The J = 1 ← 0 and J = 2 ← 1 transitions and the l-doubling transitions of J = 2 – 6 of 12CH3F in the ν2 and ν5 states were analyzed by taking into account the Coriolis interaction between the two modes. The molecular constants which are derived are: ν5 - ν2, 252 412 ± 112; , 25 611.60 ± 0.40; Aζ5, ?38 772 ± 116; , 25 432.52 ± 0.33; D, 21 838.4 ± 8.2; , 39.58 ± 0.30 MHz; in addition to a few other minor constants. The present result is completely consistent with the recent Raman data of Escribano, Mills, and Brodersen, J. Mol. Spectrosc.61, 249 (1976). Molecular constants in the ν3 and ν6 states have also been obtained: B3, 25 197.570 ± 0.020; B6, 25 418.917 ± 0.047; Aζ6ηJ, ?0.562 ± 0.030; |q6|, 8.70 ± 0.13 MHz. Errors are 2.5 times the standard deviations. 相似文献
68.
Katsutoshi Kubota Makoto Minakata Shoichi Saito Shingo Uehara 《Optical and Quantum Electronics》1978,10(3):205-210
A low drive-voltage optical modulator using a Ti-diffused UNbO3 optical waveguide has been fabricated. Stabilization against ambient temperature change was realized by using a miniature halfwave plate. The halfwave voltage, 3 dB bandwidth, optical insertion loss and extinction ratio were 3·8 V (at 1·06m wavelength), 850 MHz, 10 dB and 13 dB, respectively. A reduction scheme for the optical absorption caused by metallic electrodes, and an analysis of the modulator high frequency response are also reported. 相似文献
69.
Mitsutoshi Tanimoto Shuji Saito Yasuki Endo Eizi Hirota 《Journal of Molecular Spectroscopy》1983,100(1):205-211
The microwave spectrum of the SiF radical was observed in both and of the ground vibronic state. The SiF radical was produced by a dc discharge either in a mixture or in a transient molecule SiF2 generated by the reaction of SiF4 with heated solid silicon. The latter gave twice as intense a spectrum. A least-squares fit to the observed spectrum showed the rotational constant and the centrifugal distortion constant to be 17 350.2752(63) and 0.03188(13) MHz, respectively, with three standard errors in parentheses applying to the last digits of the constants. The lambda-doubling parameter p0 was found to be negative, ?87.67 MHz, indicating that the 2Σ+ excited state contributions dominate over those of 2Σ?. All four hyperfine coupling constants a, b, c, and d were determined and were employed to discuss the unpaired-electron spin and orbital distributions in the SiF radical. 相似文献
70.
The cw dye laser excitation spectrum of the vibronic band of HCCl was observed between 16 539 and 16 656 cm?1 with the Doppler-limited resolution, 0.03 cm?1. The HCCl molecule was generated by the reaction of discharged CF4 with CH3Cl. The observed spectra were assigned to c-type transitions with ΔKa = ±1 and also to axis-switching transitions with ΔKa = 0 or ?2, but all with K′a = 0, both for HC35Cl and HC37Cl. A rotational analysis yielded the rotational constants and quartic centrifugal distortion constants for the ground vibronic state and the band origin. A weak vibronic band, about one-third as intense as the main band, was found at about 57 cm?1 to the violet of the main band for both isotopic species, and was ascribed to a transition from the ground vibronic state to a vibrational level, possibly (041), of the à state. The rotational levels of HC35Cl in the à state showed a large perturbation; the J′ = 8, 9, and 10 levels were found to be split into two components. A normal coordinate analysis was carried out to calculate the centrifugal distortion constants and the inertia defect, which were in fair agreement with the observed values. The molecular structure of HCCl in the ground vibronic state was recalculated from the rotational constants of the two isotopic species combined with the 0.75B0 + 0.25C0 value previously reported for DC35Cl. 相似文献