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51.
Shigeo Shionoya Hiroshi Saito Eiichi Hanamura Okikazu Akimoto 《Solid State Communications》1973,12(3):223-226
Luminescence lines due to excitonic molecules are observed in CdS and CdSe. The line shape is analyzed by taking account of the broadening due to elastic collision. It is pointed out that the anisotropy of the effective hole masses makes the molecular binding energies much larger than evaluated by using the geometrical means of the hole masses. 相似文献
52.
A new type of photorearrangement of the γ-hydroxy-α, β, δ, ε-dienone, vomifoliol acetate ( 2 ) to the diketone 4 is described, and its facile rearrangement is compared with that of desoxyvomifoliol acetate ( 3 ). 相似文献
53.
Mori S Endo M Furukawa S Sunaoka M Nonaka H Ishii T Ikehira H 《Magnetic resonance imaging》2005,23(5):691-694
We developed a high radiation sensitive polymer gel by modifying the amounts of the gel components and the temperature for the gel preparation. We evaluated its relaxation time linearity against dose and compared the measured dose distribution with the calculated one. For the relaxation time-dose linearity, irradiations were carried out with a linear accelerator using 6 MV photons and doses ranging from 0-5.0 Gy. The relationship between dose and R(2) value (reciprocal of T(2) relaxation time) was measured and it had good linearity over a wide range (0.3-5 Gy). The measured dose distributions were in good agreement with calculated ones. Since the present gel has higher sensitivity and it is synthesized more easily at lower cost than conventional polymer gels, we expect to see improved three-dimensional (3D) dosimetry using it. 相似文献
54.
Anisotropic optical absorption properties of single-walled carbon nanotubes (SWNTs) are determined from a vertically aligned SWNT film for 0.5-6 eV. Absorption peaks at 4.5 and 5.25 eV are found to exhibit remarkable polarization dependence and have relevance to optical properties of graphite. A method for determining a nematic order parameter for an aligned SWNT film based on the collinear absorption peak at 4.5 eV is presented, followed by the determination of the optical absorption cross section. 相似文献
55.
Hayakawa S 《Journal of mass spectrometry : JMS》2004,39(2):111-135
Charge inversion mass spectrometry is an MS/MS method in which the electric charge of the precursor ions is opposite to that of the secondary product ions. Charge inversion mass spectrometry is classified into four types depending on the electric charge and time scale of collisions. Charge inversion mass spectrometry using collisions with gaseous targets in the keV energy collision range has provided insights into the structures and reactions of ions and neutral molecules. The characteristics of charge inversion experiments are presented in terms of the reaction endothermicities and the cross sections and their dependence on the target species. In the case of rare-gas or simple molecular targets, double-electron transfer in one collision is effective to form positive ions from negative ions, while, in the case of alkali metal targets, successive single-electron transfers in two collisions is effective to form negative ions from positive ions. On the basis of the observed target-density dependence of the product ion intensity and thermochemical considerations for internal energy distribution using thermometer molecules, the charge inversion processes using alkali metal targets have been confirmed to occur by electron transfers in successive collisions and the dissociation processes are found to occur in energy-selected neutral species formed from near-resonant neutralization with alkali metal targets. While collisionally activated dissociation (CAD) is due to dissociation of activated ions with broad internal energy distributions, the charge inversion process using alkali metal targets is due to dissociation of energy-selected neutral species with narrow internal energy distributions. The charge inversion/alkali metal spectra provide clear differentiation of the isomeric cations of C(2)H(2), C(3)H(4) and dichlorobenzenes. The CAD spectra of these isomeric cations are similar. 相似文献
56.
57.
Manabu Nakazono Yasuyuki Sato Shigeo Hasegawa Norimasa Arisuda Aiko Miyamoto Kiyoshi Zaitsu 《Chromatographia》2009,70(5-6):933-937
Rapid separation of hydrophobic compounds such as bisindolylmaleimides, indolocarbazoles or fullerene C60 derivatives by ultra performance liquid chromatography was developed. Bisindolylmaleimides and indolocarbazoles were separated within 7 and 5 min, respectively. The linear ranges for the determination of bisindolylmaleimides and indolocarbazoles were 1.25?500 pmol and 0.5?50 pmol per injection (r > 0.99), respectively. Fullerene C60 derivatives were separated within 9 min, and the linear range for the determination of fullerene C60 derivatives was 0.1?10 pmol per injection (r > 0.99). 相似文献
58.
Wenting Bu Qiuju Guo Jian Zheng Shigeo Uchida 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(2):999-1005
Surface soil samples collected in the Jiuquan region in the downwind area of the Chinese nuclear test site (CNTs) were analyzed for Pu isotopes. The 239+240Pu activities ranged from 0.025 ± 0.009 to 0.89 ± 0.16 mBq g?1, varying significantly with different sampling sites. The Dunhuang city that is located in the southwestern part of the Jiuquan region received the heaviest Pu deposition (239+240Pu activities, 0.23–0.89 mBq g?1). Most of the 240Pu/239Pu isotopic ratios were similar with that of the global fallout. However, the low values (0.080–0.147) observed in three sampling sites further supported the finding of Pu originated from CNTs in that region. 相似文献
59.
Keiki Kishikawa Yuki Furukawa Tomohiro Watanabe Michinari Kohri Tatsuo Taniguchi Shigeo Kohmoto 《Liquid crystals》2017,44(8):1332-1339
Blue phases (BPs) obtained by doping a commercially available liquid crystalline compound (4-butyl-N-(4-ethoxybenzylidene)aniline (EBBA)) with (2R,3R)-2,3-bis(4-octyloxyphenylbenzoyloxy)-N-(hydroxydecyl)succinimide (1) were highly stabilised by the addition of a small amount of alkane diols. Especially, addition of only 0.5 mol% of octane-1,8-diol increased the BP–Iso transition temperature by 10 K and widened the BP temperature range up to 35 K. A model stabilisation mechanism based on the construction of a hydrogen bond network in each disclination zone in BPs was proposed. 相似文献
60.