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Photoelectron angular distribution (PAD) in the laboratory frame for randomly oriented molecules is typically described by a single anisotropy parameter, the so-called asymmetry parameter. However, especially from a theoretical perspective, it is more natural to consider molecular photoionization by using a molecular frame. The molecular frame PADs (MFPADs) may be used to extract information about the electronic structure of the system studied. In the last decade, significant experimental efforts have been directed to MFPAD measurements. MFPADs are highly characterizing signatures of the final ionic states. In particular, they are very sensitive to the nature of the final state, which is embodied in the corresponding Dyson orbital. In our previous work on acetylacetone, a prototype system for studying intra-molecular hydrogen bond interactions, we followed the dynamics of the excited states involved in the photoexcitation–deexcitation process of this molecule. It remains to be explored the possibility of discriminating between different excited states through the MFPAD profiles. The calculation of MFPADs to differentiate excited states can pave the way to the possibility of a clear discrimination for all the cases where the recognition of excited states is otherwise intricate. 相似文献
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Continuum Mechanics and Thermodynamics - A theory of heat conduction in rigid heat conductors based entirely on mechanical concepts is proposed and compared with the traditional thermodynamic... 相似文献
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Etienne Plésiat Piero Decleva Fernando Martín 《Central European Journal of Physics》2013,11(9):1157-1162
We use an extension of the static-exchange density functional theory (DFT) method, previously reported in [E. Plésiat et al., Phys. Rev. A 2, 023409 (2012), E. Plésiat, P. Decleva, F. Martín, Phys. Chem. Chem. Phys. 31, 10853 (2012)], to evaluate vibrationally resolved (total and angular) K-shell photoelectron cross sections of methane. The calculated cross sections are in very good agreement with the existing experimental measurements at low photoelectron energies. We show that, in contrast with the rich interference patterns previously observed in molecular frame C(1s) photoelectron angular distributions of methane at both low and high photoelectron energy, no interference effects are observed in the calculated β parameters, even at high photon energies. 相似文献
38.
Lucia Calucci Emanuela Grigiotti Guido Pampaloni Calogero Pinzino Piero Zanello 《Journal of organometallic chemistry》2006,691(5):829-836
The reaction of Cr(η6-CH3C6H5)2 with 1-benzoyl-6-hydroxy-6-phenyl fulvene, dbcpH, and with pentakis(methoxycarbonyl)cyclopentadiene, pcmcpH, proceeds with evolution of dihydrogen and the formation of the ionic derivatives [Cr(η6-CH3C6H5)2][X] ([X]− = 1,2-dibenzoylcyclopentadienyl, [dbcp]−, pentakis(methoxycarbonyl)cyclopentadienyl, [pcmcp]−), which have been characterized by IR and EPR spectroscopies, X-ray diffraction and electrochemical techniques. The sterically demanding anions do not affect the structural and electronic properties of the cations in solution but strongly influence crystal packing. In fact, a rare cis-eclipsed conformation of the toluene rings is found for [Cr(η6-CH3C6H5)2][dbcp] · THF, whereas two independent complexes are observed in the unit cell of [Cr(η6-CH3C6H5)2][pcmcp], one with toluene rings in a cis-eclipsed conformation and the other in a staggered conformation (projections of methyl groups form an angle of 151°). 相似文献
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Naka Seidel Klaus Jacob Piero Zanello Marco Fontani 《Journal of organometallic chemistry》2001,620(1-2)
The reaction of {C,N-[Fe(η5-C5H5)(η5-C5H3(CH2NMe2)-2)]}Li, (FcN)Li, with zinc chloride affords the diorganozinc complex (FcN)2Zn (1). In solution, 1 appears as a mixture of rac and meso diastereomers, whereas in the solid state it crystallizes solely as a rac diastereomer. The ratio of rac/meso diastereomers in solution is solvent-, temperature- and concentration-dependent, consistent with an intermolecular exchange between diastereomers. An intramolecular dynamic phenomenon involving dissociation and recoordination of Zn---N bonds was also observed. The reaction of 1 with zinc chloride yields the monoorganozinc compound (FcN)ZnCl (2) as a slightly soluble yellow microcrystalline powder. 相似文献
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Roberto Consonni Piero Dalla Croce Raffaella Ferraccioli 《Journal of heterocyclic chemistry》1990,27(2):427-431
The 2-methyl-2H-1,2-benzothiazin-4-(3H)-one 1,1 dioxide ( 2 ), obtained according to a new, one-pot method, is transformed into the pyrrolidino enamine 3 . Reaction of p-toluenesulphonyl azide with 3 gives, via an unstable triazoline adduct which loses nitrogen, the two isomeric tosylamino derivatives 4 and 5 . The structures have been assigned by exhaustive nmr analysis and some aspects on their formation and chemical behaviour are discussed. 相似文献