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971.
Wenqian Hu Yung C. Shin Galen King 《Applied Physics A: Materials Science & Processing》2010,98(2):407-415
This paper deals with the unique phenomena occurring during the multi-burst mode picosecond (ps) laser ablation of metals
through modeling and experimental studies. The two-temperature model (TTM) is used and expanded to calculate the ablation
depth in the multi-burst mode. A nonlinear increment of ablation volume is found during the multi-burst laser ablation. The
deactivation of ablated material and the application of temperature-dependent electron-phonon coupling are demonstrated to
be important to provide reliable results. The simulation results based on this expanded laser ablation model are experimentally
validated. A significant increase of ablation rate is found in the multi-burst mode, compared with the single-pulse mode under
the same total fluence. This numerical model provides a physical perspective into the energy transport process during multi-burst
laser ablation and can be used to study the pulse-to-pulse separation time effect on the ablation rate. 相似文献
972.
This paper presents an analysis of the optimal structural features in the peacock tail feather. Peacock tail feathers are highly optimized in three respects. The feathers are highly efficient structures that can support their own weight in a deployed position. The feathers are also optimized for producing thin-film colours with a high degree of lustre. The feathers also have a structure which produces intricate patterns with a high degree of aesthetic merit. There are structural features that allow simultaneous optimization in the different areas of performance. In particular, the thin-film sandwich structure is ideal for producing optimal structural performance and optimal optical performance. 相似文献
973.
J. T. King R. G. Place Graham Edgar R. B. Purdum L. Bertiaux A. Lassieur A. Kling W. Böttger G. Meillère A. Eilert W. G. France T. S. Eckert A. de Meeus E. Lasala E. Fernandez-Espina I. Guiteras T. Callan G. W. Monier-Williams F. G. Hawley F. Glaser L. M. Dennis G. Krüss Th. P. McCutcheon Jr. P. A. van der Meulen A. B. Ray J. S. Goldbaum J. H. Reedy G. Schay Schleicher 《Analytical and bioanalytical chemistry》1925,67(9):356-368
974.
W. J. King 《Fresenius' Journal of Analytical Chemistry》1934,96(3-4):137-138
Ohne Zusammenfassung 相似文献
975.
G. E. F. Lundell H. W. Knowles J. Hanu A. Soukup O. Baudisch King Ferrari Holladay K. Schr?der J. Bellucci L. Grassi Brown Rodeja Turner Archibald und Fulton 《Fresenius' Journal of Analytical Chemistry》1922,61(1-2):60-66
Ohne Zusammenfassung
Die Zitate zu diesem Referat folgen ausnahmsweise am Schlusse des ganzen Artikels S. 66. 相似文献
976.
Andrew King 《Discrete Mathematics》2006,306(5):508-518
An indecomposable permutation π on [n] is one such that π([m])=[m] for no m<n. We consider indecomposable permutations and give a new, inclusive enumerative recurrence for them. This recurrence allows us to generate all indecomposable permutations of length n in transposition Gray code order, in constant amortized time (CAT). We also present a CAT generation algorithm for indecomposable permutations which is based on the Johnson-Trotter algorithm for generating all permutations of length n. The question of whether or not there exists an adjacent transposition Gray code for indecomposable permutations remains open. 相似文献
977.
978.
Margaret M. Curtin Carter N. Stewart McIntyre Hubert W. King Allan R. Pratt 《Journal of Non》1997,220(2-3):127-138
Slicate glass surfaces were observed over several weeks in normally humid laboratory air by atomic force microscopy. Auger spectroscopy and lateral force microscopy measurements were also made. Samples in the study include; vitreous quartz, bulk insulation glass, bulk and fibrous textile e-glass, and bulk container glass. Various features developed on these surfaces are consistent with patterns seen in crystal growth from supersaturated solution. Auger spectroscopy reveals the presence of chemically bound carbon and supports the hypothesis that these crystals are alkali and alkali earth carbonate species. The presence of these crystals is expected to affect the bonding of a coating to silicate surfaces. 相似文献
979.
Density functional theory is used to predict workfunctions, φ. For relaxed clean W(1 0 0), the local density approximation (LDA) agrees with experiment better than the newer generalized gradient approximation, probably due to the surface electron self-energy. The large Ba metallic radius indicates it covers W(1 0 0) at about 0.5 monolayer (ML). However, Ba2+, O2−, and metallic W all have similar radii. Thus 1 ML of BaO (one BaO unit for each two W atoms) produces minimum strain, indicating commensurate interfaces. BaO (1 ML) and Ba (1/2 ML) have the sameφ to within 0.02 V, so at these coverages reduction or oxidation is not important. Due to greater chemical activity of ScO vs. highly ionic BaO, when mixing the latter with this suboxide of scandia, the overlayer always has BaO as the top layer and ScO as the second layer. The BaO/ScO bilayer has a rocksalt structure, suggesting high stability. In the series BaO/ScO/, BaO/YO/, and BaO/LaO/W(1 0 0), the latter has a remarkably low φ of 1.3 V (LDA), but 2 ML of rocksalt BaO also has φ at 1.3 V. We suggest BaO (1 ML) does not exist and that it is worthwhile to attempt the direct synthesis and study of BaO (2 ML) and BaO/LaO. 相似文献
980.