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81.
H. Morita Y. Fukushima M. Yamamoto H. Fujimori 《Journal of magnetism and magnetic materials》1985,49(3):301-304
The magnetic anisotropy induced by magnetic field annealing was examined for amorphous (FexCo1-x)85Nb15 alloys produced by a sputtering technique. An appreciably large uniaxial anisotropy was observed even at x = 0. The anisotropy constant (Ku) obtained was 2.3x103 erg/cm3 at x=0, and it increased with x, showing a maximum of about 5.4x103 erg/cm3 near x = 0.2. This compositional change in Ku was explained in terms of the directional ordering of magnetic Fe-Co atom pairs under the negative nonmagnetic interaction energy leading to a precipitation. 相似文献
82.
Yukio Inoue Hirokazu Hori Takeki Sakurai Yukiko Tokitomo Junko Saito Taku Misonou 《Optical Review》2002,9(2):75-80
Optical properties of an ultraviolet-absorbing substance (UVAS) extracted from the marine red alga, Porphyra yezoensis, have been investigated. The substance is excited by UV light, and the emitted fluorescence is detected using an intelligent fluorescence detector. The fluorescence of UVAS is weaker by four orders of magnitude than the fluorescence intensity emitted by anthracene in the same optical system. The absorbed energy is apparently not transferred to the photosynthesis process and is believed to be consumed as heat. Using photothermal spectroscopy, a signal is observed indicating that the absorbed photon energy has transferred to the heat. The waveform of the photothermal signal of UVAS is similar to that of quinoxaline, whose fluorescence quantum yield is known to be zero. It is determined that the fluorescence quantum yield and the energy of the triplet state of UVAS are 1.7 ± 0.7 ± 10−4 and 21000 ± 1000 cm −1, respectively. The conclusion is that the excited molecules of UVAS decay by passing through the triplet state and dissipate all absorbed energy as heat. 相似文献
83.
Kiyohisa Fujimori Gregory T. Trainor Marion J. Costigan 《Journal of polymer science. Part A, Polymer chemistry》1984,22(10):2479-2487
A 1:1 hydrogen-bonded complex was formed between acrylic acid (AA) or methacrylic acid (MA) and the pyridine group of poly(4-vinylpyridine) (P4VP) in dilute solutions. A shift of infrared absorption of the hydrogen-bonded acid O? H to a lower energy direction and an upfield shift of acid proton in the NMR were observed when the monomers were added with pyridine. The equilibrium constants of the 1:1 complexation with P4VP measured by using a semipermeable membrane were 0.58 and 0.26 for AA and MA, respectively, at 25°C in methanol. The bromometrically measured initial rate of radical polymerization showed only a slight enhancement in the presence of P4VP, the rate being maximum at the 4VP unit:monomer mole ratio of 0.25 and 0.5 for AA and MA, respectively, in dilute methanol solution at 60°C. 相似文献
84.
Y. Nakagawa Y. Tanji H. Morita H. Hiroyoshi H. Fujimori 《Journal of magnetism and magnetic materials》1979,10(2-3):145-151
Fe-Ni Invar alloys exhibit anomalies in thermodynamic and physical properties at high temperatures. This is considered to result from the tendency to two-phase separation in the fcc phase. This idea is supported also by interdiffusion experiments in the Fe-Ni system, where the interdiffusion coefficient is anomalously small in the Invar region at lower temperatures. A simple theory of regular solutions based on a pair interaction model is applied to the Fe-Ni system; with the assumption of two gamma states this gives a miscibility gap in the Invar region. 相似文献
85.
Masao Shiozaki Yukiko Watanabe Toshio Kaneko Daisuke Tanaka Shin-ichi Kurakata 《Tetrahedron》2005,61(21):5101-5122
Lipid A analogues containing glucose in substitution for glucosamine on the reducing end were synthesized, and the inhibitory activities on LPS-induced TNFα production (LPS-antagonistic activity) in vitro using human whole blood cells were measured. The IC50 values (nM) of these ten compounds, 8, 14, 21, 31, 40, 51, 57, 62, 67 and 72, were 11.2, 15.4, 2.7, 0.1, 0.4, 1.3, 3.2, 3.2, 1.4 and 14.4, respectively. And also inhibitory activities (ID50) on TNFα production toward galactosamine loaded C3H/HeN mice in vivo of compounds 21, 31, 57, 62 and 67 were measured. The values of these compounds were 0.29, 0.50, 0.61, not dose-dependent and 0.33 mg/kg, respectively. 相似文献
86.
Yamagami C Hamasaki A Kumagai Y Moritoki T Tanahashi T 《Chemical & pharmaceutical bulletin》2005,53(4):398-401
We recently proposed a new hydrogen-accepting scale, S(HA), on the basis of the heat of formation calculated by the conductor-like screening model (COSMO) method. In this work, the same approach was applied to a series of compounds with a common hydrogen-donor group. Thus the S(HA) values for monosubstituted phenols were calculated and used for correlating their log P(oct) values (P(oct): 1-octanol/water partition coefficient) with log P(CL) (P(CL): chloroform/water partition coefficient) and log P(E) (P(E): butyl ether/water partition coefficient). It was demonstrated that the S(HA) parameter works effectively, providing excellent correlations whose physicochemical meanings are well rationalized in terms of hydrogen-bonding characteristics of the substituents. 相似文献
87.
Tin chlorides, SnCl2 and SnCl4.5H2O are excellent catalysts for the reactions of trioses, dihydroxyacetone and glyceraldehyde with alcohols (MeOH, EtOH and nBuOH) to give alkyl lactates, whose reaction mechanism involves the intermediary formation of pyruvic aldehyde followed by its esterification, which is distinctively promoted by tin halides. 相似文献
88.
Tilley RD Warner JH Yamamoto K Matsui I Fujimori H 《Chemical communications (Cambridge, England)》2005,(14):1833-1835
Silicon nanocrystals with a uniform size distribution were synthesized in inverse micelles using powerful hydride reducing agents. The silicon nanocrystals surfaces were then stabilized with 1-heptene to produce particles with strong blue photoluminescence. 相似文献
89.
The electronic structure of TiH2 has been studied using the augmented-plane-wave method and the LCAO interpolation. The density of states and its orbital components show that the conduction band is Ti d-like and that the valence band is largely derived from the hydrogen orbitals with small Ti 3d hybridization. The electronic charges on the hydrogen atom are ~ 1.5 as compared to 1.6–1.7 of the rare-earth metal hydrides. 相似文献
90.
Arenesulfonic acids, its sodium salts, and alkyl arenesulfonates were reduced readily to the corresponding arenethiols quantitatively with triphenylphosphine in the presence of iodine. 相似文献