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971.
Hiroshi TOKI Kenji SATO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(2):29-46
In modern life, we are surrounded by and filled with electromagnetic noise caused by the dominant use of energy in the form of electricity. This situation is brought about by the fact that the noise is not understood theoretically. A new practice of noise reduction was introduced for the construction of Heavy Ion Medical Accelerator in Chiba (HIMAC). The key concept is a symmetric three-line circuit that arranges power supplies, noise filters and magnets around a third central ground line. A continuous theoretical effort forced us to find a new circuit theory involving a multiconductor transmission-line system starting from Maxwell’s equations without any approximation. We discuss the essence of all of these experimental and theoretical developments with the hope to remove unnecessary electromagnetic noise not only from power supplies, but also from all electric devices. The newly derived circuit theory of multiconductor transmission lines is universal, and establishes the validity of the practice of noise reduction. 相似文献
972.
Masahiro Yoshida Kenji Ishii Ignace Jarrige Tetsu Watanuki Kazutaka Kudo Yoji Koike Ken'ichi Kumagai Nozomu Hiraoka Hirofumi Ishii Ku‐Ding Tsuei Jun'ichiro Mizuki 《Journal of synchrotron radiation》2014,21(1):131-135
A single‐crystal momentum‐resolved resonant inelastic X‐ray scattering (RIXS) experiment under high pressure using an originally designed diamond anvil cell (DAC) is reported. The diamond‐in/diamond‐out geometry was adopted with both the incident and scattered beams passing through a 1 mm‐thick diamond. This enabled us to cover wide momentum space keeping the scattering angle condition near 90°. Elastic and inelastic scattering from the diamond was drastically reduced using a pinhole placed after the DAC. Measurement of the momentum‐resolved RIXS spectra of Sr2.5Ca11.5Cu24O41 at the Cu K‐edge was thus successful. Though the inelastic intensity becomes weaker by two orders than the ambient pressure, RIXS spectra both at the center and the edge of the Brillouin zone were obtained at 3 GPa and low‐energy electronic excitations of the cuprate were found to change with pressure. 相似文献
973.
Joachim Krieger Kenji Nakanishi Wilhelm Schlag 《Communications in Mathematical Physics》2014,327(1):309-332
For the critical focusing wave equation ${\square u = u^5 \, {\rm on} \, \mathbb{R}^{3+1}}$ in the radial case, we establish the role of the “center stable” manifold ${\Sigma}$ constructed in Krieger and Schlag (Am J Math 129(3):843–913, 2007) near the ground state (W, 0) as a threshold between blowup and scattering to zero, establishing a conjecture going back to numerical work by Bizoń et al. (Nonlinearity 17(6):2187–2201, 2004). The underlying topology is stronger than the energy norm. 相似文献
974.
Improved calculation of band gap of Sr2Bi2O5 crystal using modified Becke–Johnson exchange potential
Yuki Obukuro Shigenori Matsushima Kenji Obata Masao Arai Kenkichiro Kobayashi 《Journal of Physics and Chemistry of Solids》2014
The electronic structure of Sr2Bi2O5 is calculated by the scalar-relativistic full potential linearized augmented plane wave (FLAPW+lo) method using the modified Becke–Johnson potential combined with the local density approximation correlation (MBJ–LDA). Both the valence band maximum (VBM) and conduction band minimum (CBM) exist at the Γ-point, indicating that Sr2Bi2O5 is a direct-band-gap material. The band gap is calculated to be 3.17 eV, which is very close to the experimental value. This result is in great contrast to the underestimation based on the GGA calculation. On the other hand, there is only a small difference in the effective masses of holes and electrons photogenerated near the VBM and CBM for the MBJ–LDA and GGA approaches. The optical properties of Sr2Bi2O5 are calculated from the complex dielectric function ε(ω)=ε1(ω)+iε2(ω). A highly polarized peak is observed at 3.5 eV in the ε2(ω) function. Furthermore, the absorption coefficient estimated from the MBJ–LDA is very similar to that from the experimental result. 相似文献
975.
976.
977.
Otake K Azukizawa S Takahashi K Fukui M Shibabayashi M Kamemoto H Kasai M Shirahase H 《Chemical & pharmaceutical bulletin》2011,59(7):876-879
2-Acyl-tetrahydroisoquinoline-3-carboxylic acid derivatives were synthesized and biologically evaluated. (S)-2-(2,4-Hexadienoyl)-7-[2-(5-methyl-2-phenyloxazol-4-yl)ethoxy]-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (14) showed peroxisome proliferator-activated receptor γ (PPARγ) and PPARα agonist activities and protein-tyrosine phosphatase 1B (PTP-1B) inhibitory activities. PPARγ agonist activity of 14 was comparable to that of rosiglitazone, and PTP-1B inhibitory activity was about 10-fold weaker than that of ertiprotafib, a PTP-1B inhibitor. Compound 14 showed high oral absorption in rats and potent hypoglycemic effects in KK-A(y) mice. In conclusion, 14 would be an excellent lead compound for a new type of anti-diabetic drug with triple actions. 相似文献
978.
Tomoki Saka Toru Okaki Shohei Ifuku Yukiko Yamashita Kasumi Sato Shota Miyawaki Akiko Kamori Atsushi Kato Isao Adachi Yasuhiro Tezuka Peter G. Kiria Osamu Onomura Daishiro Minato Kenji Sugimoto Yuji Matsuya Naoki Toyooka 《Tetrahedron》2013
Synthesis and inhibitory activities against α-l-fucosidase of phenylalkyl-substituted polyhydroxypiperidines have been described. Among the newly synthesized compounds, 2,4,6-trichloro derivative (16q) showed very high inhibitory activity against α-l-fucosidase with IC50 value of 0.005 μM, and Ki values of 0.0011 μM, respectively. 相似文献
979.
Kenji Hotta Hideharu Ishida Makoto Kiso Akira Hasegawa 《Journal of carbohydrate chemistry》2013,32(4-5):491-506
Abstract A first total synthesis of a cholinergic neuron-specific ganglioside, GQ1bα (IV3Neu5Acα, III6Neu5Acα, II3Neu5Acα2-Gg4Cer) is described. Regio- and stereo-selective monosialylation of the hydroxyl group at C-6 of the GalNAc residue in 2-(trimethylsilyl)ethyl O-(2-acetamido-2-deoxy-3,4-O-isopropylidene-β-d-galactopyranosyl)-(1→4)-O-(2,6-di-O-benzyl-β-dgalactopyranosyl)-(1→4)- O-2,3,6-tri-O-benzyl-β-dglucopyranoside (4) with methyl (phenyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-d glycero-d galacto-2-nonulopyranosid) onate (5), and subsequent dimericsialylation of the hydroxyl group at C-3 of the Gal residue with methyl [phenyl 5-acetamido-8-O-(5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-d glycero-α-d galacto-2-nonulopyranosylono-1′,9-lactone)-4, 7-di-O-acetyl-3,5-dideoxy-2-thio-d glycero-d galacto-2-nonulopyranosid]onate (7), using N-iodosuccinimide (NIS)-trifluoromethanesulfonic acid (TfOH) as a promoter, gave the desired hexasaccharide 8 containing α-glycosidically-linked mono- and dimeric sialic acids. This was transformed into the acceptor 9 by removal of the isopropylidene group. Condensation of methyl O-(methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-d glycero-α-d galacto-2-nonulopyranosylonate)-(2→3)-2,4,6-tri-O-benzoyl-1-thio-β-dgalactopyranoside (10) with 9, using dimethyl(methylthio)sulfonium triflate (DMTST) as a promoter, gave the desired octasaccharide derivative 11 in high yield. Compound 11 was converted into α-trichloroacetimidate 14, via reductive removal of the benzyl groups, O-acetylation, removal of the 2-(trimethylsilyl)ethyl group, and treatment with trichloroacetonitrile, which, on coupling with (2S,3R,4E)-2-azido-3-O-benzoyl-4-octadecene-1,3-diol (15), gave the β-glycoside 16. Finally, 16 was transformed, via selective reduction of the azido group, coupling with octadecanoic acid, O-deacylation, and hydrolysis of the methyl ester group, into the title ganglioside 18 in good yield. 相似文献
980.
Norifumi Kishi Dr. Zhiou Li Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Kenji Yoza Prof. Dr. Jay S. Siegel Dr. Michito Yoshizawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(20):6313-6320
This article reports that an M2L4 molecular capsule is capable of encapsulating various neutral molecules in quantitative yields. The capsule was obtained as a single product by mixing a small number of components; two PdII ions and four bent bispyridine ligands containing two anthracene panels. Detailed studies of the host capability of the PdII‐linked capsule revealed that spherical (e.g., paracyclophane, adamantanes, and fullerene C60), planar (e.g., pyrenes and triphenylene), and bowl‐shaped molecules (e.g., corannulene) were encapsulated in the large spherical cavity, giving rise to 1:1 and 1:2 host–guest complexes, respectively. The volume of the encapsulated guest molecules ranged from 190 to 490 Å3. Within the capsule, the planar guests adopt a stacked‐dimer structure and the bowl‐shaped guests formed an unprecedented concave‐to‐concave capsular structure, which are fully shielded by the anthracene shell. Competitive binding experiments of the capsule with a set of the planar guests established a preferential binding series for pyrenes≈phenanthrene>triphenylene. Furthermore, the capsule showed the selective formation of an unusual ternary complex in the case of triphenylene and corannulene. 相似文献