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91.
G. Lhersonneau B. Pfeiffer J. Alstad P. Dendooven K. Eberhardt S. Hankonen I. Klöckl K.-L. Kratz A. Nähler R. Malmbeck J.P. Omtvedt H. Penttilä S. Schoedder G. Skarnemark N. Trautmann J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):285-297
The decay of 111Ru obtained from fast on-line chemical and mass separation has been investigated by β-γ-t and γ-γ coincidence techniques. Earlier spin and parity assignments of 111Rh levels based on extrapolations of level systematics are confirmed. In particular, the K=1/2 intruder band is supported
by the hindrance of E2 transitions between deformed and spherical states and enhancement of intraband E2 transitions. The
excitation energies of intruder band members in Rh isotopes show a minimum at 109Rh64, with two neutrons less than 111Rh at the N=66 midshell. This trend, which differs from the one in the higher-Z neighbouring elements Ag and Cd with minima
at N=66, follows the evolution of deformation observed in the lower-Z elements Ru and Mo.
Received: 25 June 1997 / Revised version: 10 September 1997 相似文献
92.
T. Böske W. Clemens D. Schmitz J. Kojnok M. Schäfer V. Cros G. Y. Guo W. Eberhardt 《Applied Physics A: Materials Science & Processing》1995,61(2):119-122
The coupling of Cr to Fe in stacked Cr/Fe/Cr trilayers is studied by circular magnetic X-ray dichroism using fluorescence yield to monitor the absorption. From the dichroic spectra, we determine the thickness dependent average magnetic coupling of Cr to Fe for Cr layer thicknesses of 1, 2 and 3 ML. We compare our results to new calculated spectra. Additionally, all Cr spectra show significant contributions due to photon scattering processes at theL
2, 3 absorption edges depending on the degree of circular polarization. 相似文献
93.
94.
On the way towards novel supramolecular assemblies and polymers, several copper(II) complexes consisting of one terpyridine as well as one bipyridine ligand were synthesized in a one‐step reaction. The compounds were characterized by UV/VIS spectroscopy and MALDI‐TOF mass spectrometry. Single crystals were obtained and their structures were determined by X‐ray analyses. 相似文献
95.
96.
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98.
Markus Allmendinger Robert Eberhardt Ferenc Molnar 《Journal of organometallic chemistry》2004,689(5):971-979
In situ ATR-IR spectroscopy is applied as a powerful tool to study the factors that control the reaction of epoxides with carbon monoxide in the presence of [Lewis acid]+[Co(CO)4]− salts. Based on these investigations, a consistent mechanistic scheme is presented, comprising the main lactone and polyester products and minor components, e.g., acetone and crotonic acid derivatives. β-Alkoxy-acyl-cobalttetracarbonyl species are shown to be key intermediates from which two reaction routes start in dependence of the applied Lewis acid (LA). Labile LA-alkoxy combinations favor a backbiting process of the oxygen function on the Co-acyl bond, primarily producing lactone products. More stable LA-alkoxy entities are unreactive toward PO conversion and afford a polymerization reaction after the addition of a nucleophile. In that case, the Lewis acid remains bonded to the chain end. 相似文献
99.
Amide-amide hydrogen bonds have been implicated in directing protein folding and enhancing protein stability. Inversion transfer (13)C NMR spectroscopy and IR spectroscopy were used to compare the ability of various amide solvents and of water to alter the rate of the cis-trans isomerization of the prolyl peptide bond of Ac-Gly-[β,δ-(13)C]Pro-OMe and the amide I vibrational mode of [(13)C=O]Ac-Pro-OMe. The results indicate that secondary amides are significantly weaker hydrogen bond donors than is formamide or water. These results are most consistent with models for protein folding in which the formation of secondary structure is a cooperative process that follows hydrophobic collapse. These results also suggest that a hydrogen bond between a main-chain oxygen and an asparagine or glutamine sidechain may contribute more to protein stability than does a main-chain-main-chain hydrogen bond. 相似文献
100.
S. Suzuki M. Kohno H. Shiromaru Y. Achiba H. Kietzmann B. Kessler G. Ganteför W. Eberhardt 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):407-409
Mass spectra of LaC n - were taken by using a laser-vaporization source (LVS) and pulsed arc cluster ion source (PACIS) applied to La-carbon composite rods (1:130 atomic ratio). The mass spectrum using the LVS with annealing procedure has shown several magic numbers for LaC n - (n = 44, 50, 60, and 70), whereas only small LaC n - (up to n = 14) have been observed in the mass spectrum using the PACIS. Photoelectron spectra of some of these have been measured using a magnetic-bottle type time-of-flight electron spectrometer. These results indicate the exsistence of a few conformational isomers for small La-containing carbon cluster negative ions LaC n - (n = 5–8). 相似文献