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191.
Ellie Kim Yana Vaynzof Alessandro Sepe Maik Scherer Pedro Cunha Stephan V. Roth Ullrich Steiner 《Advanced functional materials》2014,24(6):863-872
3D continuous ZnO morphologies with characteristic feature sizes on the 10 nm length scale are attractive for electronic device manufacture. However, their synthesis remains a challenge because of the low crystallization temperature of ZnO. Here, we report a method for the robust and reliable synthesis of fully crystalline 3D mesoporous ZnO networks by means of atomic layer deposition (ALD) of ZnO into a self‐assembled block copolymer template. By carefully optimizing the processing conditions we are able to synthesize several‐micrometer‐thick layers of mesoporous ZnO networks with a strut width of 30 nm. Two 3D mesoporous morphologies are manufactured: a periodic gyroid structure and a random worm‐like morphology. Exploiting the ALD property to conformally coat complex surfaces of high aspect ratio, the channel network of a 3D continuous channel network of a self‐assembled block copolymer is replicated into ZnO. X‐ray photoemission spectroscopy and x‐ray diffraction measurements reveal that the chemical composition of the mesoporous structures is uniform and consists of wurtzite‐ZnO throughout the film. Scanning electron microscopy reveals an average pore dimension of 30 nm. The potential of this material for a hybrid photovoltaic application is demonstrated by the manufacture of a poly(3‐hexylthiophene)/ZnO solar cell. 相似文献
192.
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
193.
194.
195.
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
196.
197.
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
198.
199.
Thomas S. Ullrich 《Pramana》2004,62(2):465-481
QCD predicts a phase transition between hadronic matter and a quark-gluon plasma at high energy density. The relativistic
heavy ion collider (RHIC) at Brookhaven National Laboratory is a new facility dedicated to the experimental study of matter
under extreme conditions. Already the first round of experimental results at RHIC indicated that the conditions to create
a new state of matter are indeed reached in the collisions of heavy nuclei. Studies of particle spectra and their correlations
at low transverse momenta provide evidence of strong pressure gradients in the highly interacting dense medium and hint that
we observe a system in thermal equilibrium. Recent runs with high statistics allow us to explore the regime of hard-scattering
processes where the suppression of hadrons at large transverse momentum, and quenching of di-jets are observed thus providing
further evidence for extreme high density matter created in collisions at RHIC. 相似文献
200.
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