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121.
Tatiana Y. Karogodina Igor G. Dranov Dr. Svetlana V. Sergeeva Dr. Dmitry V. Stass Prof. Dr. Ulrich E. Steiner 《Chemphyschem》2011,12(9):1714-1728
Oxidation of dihydrorhodamine 123 (DHR) to rhodamine 123 (RH) by oxoperoxonitrite (ONOO?), formed through recombination of NO and O2.? radicals resulting from thermal decomposition of 3‐morpholinosydnonimine (SIN‐1) in buffered aerated aqueous solution at pH 7.6, represents a kinetic model system of the reactivity of NO and O2.? in biochemical systems. A magnetic‐field effect (MFE) on the yield of RH detected in this system is explored in the full range of fields between 0 and 18 T. It is found to increase in a nearly linear fashion up to a value of 5.5±1.6 % at 18 T and 23 °C (3.1±0.7 % at 40 °C). A theoretical framework to analyze the MFE in terms of the magnetic‐field‐enhanced recombination rate constant krec of NO and O2.? due to magnetic mixing of T0 and S spin states of the radical pair by the Δg mechanism is developed, including estimation of magnetic properties (g tensor and spin relaxation times) of NO and O2.? in aqueous solution, and calculation of the MFE on krec using the theoretical formalism of Gorelik at al. The factor with which the MFE on krec is translated to the MFE on the yield of ONOO? and RH is derived for various kinetic scenarios representing possible sink channels for NO and O2.?. With reasonable assumptions for the values of some unknown kinetic parameters, the theoretical predictions account well for the observed MFE. 相似文献
122.
123.
P. Steiner S. Hüfner A. Jungmann V. Kinsinger I. Sander 《Zeitschrift für Physik B Condensed Matter》1989,74(2):173-182
Photoemission valence band spectra with three different photon energies (21.2 eV, 40.8 eV, 1253.6 eV) for Cu2O and CuO and a number of copper oxide based superconducting ceramics are investigated, namely La2CuO4 (LCO), Y1Ba2Cu3O7 (YBCO), Bi2Sr2CaCu2O8 (BSCCO) and Tl2Ba2Ca2Cu3O10 (TBCCO). From the Cu2O data it can be infered, that the He-II (40.8 eV) spectra give a fair representation of the density of states (DOS). In addition the agreement between the calculated density of states (DOS) and the He-II photoemission spectrum is almost perfect for Cu2O. This agreement is worse for CuO and the other materials which all have a Cu groundstate close to a 3d
9 configuration indicating a large contribution of thed-d correlation energy to the excitation spectra which is absent in Cu2O because of the filled 3d-shell. In all cases the experimental DOS atE
F is very small and only the spectra of BSCCO show a well defined Fermi edge. The relevance of these findings with respect to the theoretical local functional density DOS calculations is discussed. 相似文献
124.
125.
126.
F. Reinert P. Steiner R. Zimmermann R. Claessen S. Hüfner 《Zeitschrift für Physik B Condensed Matter》1995,99(1):229-234
The valence band of potassium permanganate (KMnO4) was investigated by means of resonant photoemission spectroscopy (ResPES) at the Mn2p, Mn3p and O1s edge. These data confirm
the previous conclusions of a strong deviation from a purely ionic charge distribution in this compound. The ResPES data are
in agreement with previous results about the character of the individual valence band states. A simple cluster model is used
to explain qualitatively the different structures seen in the valence band spectra and their dependence on the photon energy. 相似文献
127.
128.
Bert Lutz Jan A. Kanters John van der Maas Jan Kroon Thomas Steiner 《Journal of Molecular Structure》1998,440(1-3)
Structural and IR-spectroscopic evidence is given that directed contacts from terminal alkynes to C=C double bonds possess the essential characteristics of weak hydrogen bonds. The contacts are directed at the center of the π-bond rather than at one of the individual C-atoms. The contact distances from H to the center of the C=C bond are typically 2.8 Å, with the shortest distances being 2.5 Å. The interaction is of pronounced long-range nature and can be detected in the infrared spectrum even with a long H…π distance of almost 3.0 Å. The sample used is mainly composed of ethynyl steroids belonging to the progestine family. 相似文献
129.
130.
R. Baur A. Breskin R. Chechik A. Drees C. Jacob U. Faschingbauer P. Fischer Z. Fraenkel E. Gatti P. Glässel Th. Günzel C. P. de los Heros F. Hess D. Irmscher B. Lenkeit L. H. Olsen Y. Panebrattsev A. Pfeiffer I. Ravinovich P. Rehak A. Schön J. Schukraft J. Schukraft M. Sampietro A. Shor H. J. Specht V. Steiner S. Tapprogge G. Tel-Zur I. Tserruya Th. Ullrich J. P. Wurm 《Zeitschrift fur Physik C Particles and Fields》1997,74(4):593-594