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101.
102.
D. Seweryniak B. Cederwall J. Nyberg C. Fahlander A. Johnson A. Kerek J. Kownacki L. -O. Norlin E. Adamides A. Atac J. Blomqvist H. Grawe E. Ideguchi R. Julin S. Juutinen W. Karczmarczyk S. Mitarai M. Piiparinen R. Schubart G. Sletten S. Törmänen A. Virtanen 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(2):243-244
Neutron deficient nuclei close to 100Snhave been investigated in-beam by γ-ray spectroscopic methods using the NORDBALL detector array. A beam of 270 MeV 58Niwas used to bombard a target of 54Fe.Reaction channel separation was achieved with a 4π charged particle multidetector setup together with a 1π neutron detector wall placed in the forward direction. Excited states of 102Inwere identified for the first time. The level scheme constructed from γ-γ-particle-coincidence and γ-γ-angular correlation analysis is presented. The structure of 102 In is discussed and compared to neighboring nuclei in the framework of the nuclear shell-model. 相似文献
103.
Juan B. Arellano B. Bangar Raju† K. Razi Naqvi Tomas Gillbro‡ 《Photochemistry and photobiology》1998,68(1):84-87
Abstract— In this short communication we present the stoichiometric ratio of bacteriochlorophyll, bacteriopheophytin and carotenoids in a few photosynthetic purple bacteria complexes (whose two-dimensional or three-dimensional structures are well known) determined using the spectrum-reconstruction method (SRCM). An important conclusion of our pigment stoichiometric analysis is the evidence for the absence of the second carotenoid in the light-harvesting complex 2 (LH2). In the process, we also highlight the useful application of SRCM in determining the molar extinction coefficients of carotenoids present in LH1, LH2 or reaction centers for which these values are not known due to isolation problems and/or stability. 相似文献
104.
105.
S.R. Bare K. Griffiths P. Hofmann D.A. King G.L. Nyberg N.V. Richardson 《Surface science》1982,120(2):367-375
Using both synchrotron and HeII radiation the electronic and geometric structure of Pt{110}-(2×1)p1g1 CO was examined. The shape resonance for the 4σ orbital of CO is found to be peaked at 38 eV, while that for the 5σ orbital is peaked at 28 eV. No shape resonance is observed from the 1π orbital. The ordering is reversed from that of gas phase CO. Further evidence, from the polar intensity variation of the non-bonding 4σ orbital, is presented for the tilted CO structure proposed previously. 相似文献
106.
Predictions of the “redox” and “complex” schemes for the Fe3+ catalyzed decomposition of H2O2 have been compared with published and new experimental data by numerical integratior of the appropriate complete sets of differential equations. Apparent discrepancies for the redox scheme at high Fe3+/H2O2 ratios are shown to disappear in the complete treatment, and inconsistencies of the complex scheme with both kinetic data and spectroscopic measurements are pointed out. 相似文献
107.
108.
Ajay N. Jain Thomas G. Dietterich Richard H. Lathrop David Chapman Roger E. Critchlow Jr. Barr E. Bauer Teresa A. Webster Tomas Lozano-Perez 《Journal of computer-aided molecular design》1994,8(6):635-652
Summary Building predictive models for iterative drug design in the absence of a known target protein structure is an important challenge. We present a novel technique, Compass, that removes a major obstacle to accurate prediction by automatically selecting conformations and alignments of molecules without the benefit of a characterized active site. The technique combines explicit representation of molecular shape with neural network learning methods to produce highly predictive models, even across chemically distinct classes of molecules. We apply the method to predicting human perception of musk odor and show how the resulting models can provide graphical guidance for chemical modifications. 相似文献
109.
Attempts to characterize nucleic acid-silver interactions raise questions about how the free nucleic acid bases interact with silver ions in dilute aqueous solution. Studies of ultraviolet and infrared dichroism lead to the conclusion that with silver(I) ions in dilute solution adenine forms linear polymers, whereas 1-methyladenine forms dimers. The composition and structure of the complexes are further discussed against the background of the spectroscopic results. 相似文献
110.
We present a novel Monte Carlo algorithm for N diffusing finite particles that react on collisions. Using the theory of first-passage processes and time dependent Green's functions, we break the difficult N-body problem into independent single- and two-body propagations circumventing numerous diffusion hops used in standard Monte Carlo simulations. The new algorithm is exact, extremely efficient, and applicable to many important physical situations in arbitrary integer dimensions. 相似文献