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101.
Natalia Calonghi Carla Boga Patrizia Nitti Dario Telese Silvia Bordoni Giovanna Farruggia Fioretta Asaro Martina Grandi Chiara Zalambani Gabriele Micheletti 《Molecules (Basel, Switzerland)》2022,27(8)
A series of regioisomers of the hydroxystearic acid (HSA) was prepared, and the effect of the position of the hydroxyl group along the chain on a panel of human cancer cell lines was investigated. Among the various regioisomers, those carrying the hydroxyl at positions 5, 7, and 9 had growth inhibitor activity against various human tumor cell lines, including CaCo-2, HT29, HeLa, MCF7, PC3, and NLF cells. 10-HSA and 11-HSA showed a very weak effect. 8-HSA did not show inhibitory activity in all cell lines. The biological role of 7-HSA and 9-HSA is widely recognized, while little is known about the effects of 5-HSA. Therefore, the biological effects of 5-HSA in HeLa, HT29, MCF7, and NLF cell lines were investigated using the Livecyte’s ptychography technology, which allows correlating changes in proliferation, motility, and morphology as a function of treatment at the same time. 5-HSA not only reduces cell proliferation but also induces changes in cell displacement, directionality, and speed. It is important to characterize the biological effects of 5-HSA, this molecule being an important component of fatty acyl esters of hydroxy fatty acids (FAHFA), a class of endogenous mammalian lipids with noticeable anti-diabetic and anti-inflammatory effects. 相似文献
102.
The Armstrong model of the Schuknecht gel foam and wire prosthesis was tested in the magnetic field of a 1.5 Tesla magnet. The wire component of the prosthesis was found to be non-magnetic. Patients with this prosthesis can therefore undergo MRI examination safely. Two previous articles from the non radiologic literature concerning the magnetic properties of metallic middle ear prostheses are reviewed. 相似文献
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Gabriele Weirauch Alain Campargue Hans Bürger 《Journal of Molecular Spectroscopy》2002,216(1):113-121
The nν1 SiH stretching overtone transitions of trideuterosilane, HSiD3, have been recorded by Fourier transform spectroscopy (n=3 and 4) and by intracavity laser absorption spectroscopy (n=5 and 6). The unusually weak 3ν1 band is affected by considerable intensity and energy perturbations. The 4ν1 band is also strongly perturbed but the interaction with the dark states is more limited and part of the rotational structure of the v1=4 upper state could be satisfactorily modeled. Less pronounced perturbations affect the v1=5 level, newly detected by ICLAS. Its rotational structure is locally perturbed by anharmonic coupling with an unidentified vibrational dark state. The global modeling of the interacting dyad allowed the determination of the perturber parameters and the assignment of extra lines due to an intensity transfer from the v1=5 bright state to the dark state. In agreement with a previous ICLAS study, the 6ν1 band near 12 113 cm−1 was found free of perturbation. About six hundred line positions could be reproduced with an rms of 4.6×10−3 cm−1, leading to a significantly improved set of rovibrational parameters. The striking evolution of the rotational structure, which exhibits fewer and fewer perturbations when the SiH excitation increases, is discussed. 相似文献
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It is shown that radiation pressure can be profitably used to entangle macroscopic oscillators like movable mirrors, using present technology. We prove a new sufficient criterion for entanglement and show that the achievable entanglement is robust against thermal noise. Its signature can be revealed using common optomechanical readout apparatus. 相似文献
107.
Marina S. Fonari Yurii A. Simonov Victor Ch. Kravtsov Janusz Lipkowski Gabriele Bocelli Edward V. Ganin Vladimir O. Gelmboldt 《Journal of chemical crystallography》1999,29(12):1245-1254
Synthesis and single-crystal X-ray structures are recorded for three adducts of SbF3 with different azacrown ethers. [SbF3·H2O·L1], 1, (L1 = 12,13-benz-1,10-di(azamethyl)-4,7-dioxacyclotetradecane-1,14-dione), triclinic,
, a = 11.234(2), b = 11.691(2), c = 8.869(2) Å, = 94.66(3), = 113.12(3), = 67.82(3)°, Z = 2. [SbF3Cl·H2O·(HL2)], 2, (L2 = monoaza-18-crown-6), orthorhombic, P212121, a = 8.763(2), b = 13.003(3), a = 16.836(3) Å, Z = 4. [(SbF3)2Cl2·(H2L3)], 3, (L3 = 1,10-diaza-18-crown-6), triclinic,
, a = 8.284(2), b = 9.016(2), c = 9.134(2) Å, = 82.92(3), = 65.24(3), = 63.38(3)°, Z = 1. All three structures include SbF3 neutral molecules in the pyramidal mode and the antimony second coordination sphere is completed up to six in different fashions. In 1 the dimeric (SbF3)2 adducts are made up due to the involvement of the symmetry-related fluorine atom in coordination. The distorted octahedron is then completed by water molecule and carbonyl oxygen of L1. The neutral molecules are joined by coordination and hydrogen bonds in the infinite ribbons. 2 and 3 are both comprised of neutral and charged species also bounded via coordination and hydrogen bonds. L2 and L3 in the complexes adopt the form of single and double-charged cations, respectively. The inorganic backbone unites the neutral SbF3 molecules and chloride anions in the alternative mode. The sixth coordination site in the antimony polyhedron is completed by the water molecule in 2 and the ethereal oxygen atom in 3. Alignment of the inorganic entities within the structures of 2 and 3 is strikingly similar. Hydrogen bonding patterns are discussed. 相似文献
108.
M. Costa G. P. Chiusoli R. Gaetti B. Gabriele G. Salerno 《Russian Chemical Bulletin》1998,47(5):936-940
New rhodium-catalyzed amination reactions of arylacetylenes and cyclohexen-1-ylacetylene in the presence of strong bases with
the use of carbon dioxide as an auxiliary are described. Secondary amines attack the terminal carbon atom of the triple bond
followed by protonation of the adjacent carbon atom. Alternatively, the reaction can proceed further with the addition of
the second alkyne molecule. The conditions for the selective synthesis of enamines (up to 87% yield) or α-substituted propynylamines
(up to 86% yield) are reported.
Dipartimento di Chimica Organica e Industriale dell'Università, Viale delle Scienze, I-43100 Parma, Italia.
Dipartimento di Chimica, Università della Calabria, Arcavacata di Rende, I-80036 Cosenza, Italia.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 966–970, May, 1998. 相似文献
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