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71.
L. W. Andrews H. Morawitz E. Rupp H. Bauer W. F. Schirmer Karin Thaulow H. Lescoeur E. Biilman F. Lehmann J. Knox P. W. Robertson H. Wastenson G. S. Jamieson F. Utz L. Garnier F. Reinthaler J. A. Muller A. Kolb A. Feldhofen G. Adanti B. Oddo L. Vignon H. R. Procter und R. A. Seymour-Jones 《Fresenius' Journal of Analytical Chemistry》1923,62(10):401-407
Ohne Zusammenfassung 相似文献
72.
73.
Antony V. Wilson Timothy Nguyen Felix Brosi Xuefeng Wang Lester Andrews Sebastian Riedel Adam J. Bridgeman Nigel A. Young 《ChemInform》2016,47(14):no-no
Binary palladium fluorides from PdF to PdF6 are investigated by matrix‐isolation methods using thermal evaporation and laser ablation to generate Pd atoms for reaction with F2‐doped Ar and Ne matrices as well as neat F2 matrices. 相似文献
74.
Eric S. Simon Panagiotis G. Papoulias Philip C. Andrews 《Journal of the American Society for Mass Spectrometry》2010,21(9):1624-1632
The fragmentation characteristics of peptides derivatized at the side-chain ε-amino group of lysyl residues via reductive
amination with benzaldehyde have been examined using collision-induced dissociation (CID) tandem mass spectrometry. The resulting
MS/MS spectra exhibit peaks representing product ions formed from two independent fragmentation pathways. One pathway results
in backbone fragmentation and commonly observed sequence ion peaks. The other pathway corresponds to the unsymmetrical, heterolytic
cleavage of the Cζ-Nε bond that links the benzyl derivative to the side-chain lysyl residue. This results in the elimination of the derivative
as a benzylic or tropylium carbocation and a (n − l)+-charged peptide product (where n is the precursor ion charge state). The frequency of occurrence of the elimination pathway
increases with increasing charge of the precursor ion. For the benzylmodified tryptic peptides analyzed in this study, peaks
representing products from both of these pathways are observed in the MS/MS spectra of doubly-charged precursor ions, but
the carbocation elimination pathway occurs almost exclusively for triply-charged precursor ions. The experimental evidence
presented herein, combined with molecular orbital calculations, suggests that the elimination pathway is a charge-directed
reaction contingent upon protonation of the secondary ε-amino group of the benzyl-derivatized lysyl side chain. If the secondary
ε-amine is protonated, the elimination of the carbocation is observed. If the precursor is not protonated at the secondary
ε-amine, backbone fragmentation persists. The application of appropriately substituted benzyl analogs may allow for selective
control over the relative abundance of product ions generated from the two pathways. 相似文献
75.
Theresa Hague Andrea Petroczi Paul LR Andrews James Barker Declan P Naughton 《Chemistry Central journal》2010,4(1):2
This is a correction to the following paper: Hague T, Petroczi A, Andrews PR, Barker J, Naughton DP: Determination of metal
ion content of beverages and estimation of target hazard quotients: a comparative study. Chem Central J 2008, 2:13. 相似文献
76.
An ocean acoustic waveguide remote sensing system can instantaneously image and continuously monitor fish populations distributed over continental shelf-scale regions. Here it is shown theoretically that the areal population density of fish groups can be estimated from their incoherently averaged broadband matched filtered scattered intensities measured using a waveguide remote sensing system with less than 10% error. A numerical Monte-Carlo model is developed to determine the statistical moments of the scattered returns from a fish group. It uses the parabolic equation to simulate acoustic field propagation in a random range-dependent ocean waveguide. The effects of (1) multiple scattering, (2) attenuation due to scattering, and (3) modal dispersion on fish population density imaging are examined. The model is applied to investigate population density imaging of shoaling Atlantic herring during the 2006 Gulf of Maine Experiment. Multiple scattering, attenuation and dispersion are found to be negligible at the imaging frequencies employed and for the herring densities observed. Coherent multiple scattering effects, such as resonance shifts, which can be significant for small highly dense fish groups on the order of the acoustic wavelength, are found to be negligible for the much larger groups typically imaged with a waveguide remote sensing system. 相似文献
77.
Florian Meirer Jordi Cabana Yijin Liu Apurva Mehta Joy C. Andrews Piero Pianetta 《Journal of synchrotron radiation》2011,18(5):773-781
The ability to probe morphology and phase distribution in complex systems at multiple length scales unravels the interplay of nano‐ and micrometer‐scale factors at the origin of macroscopic behavior. While different electron‐ and X‐ray‐based imaging techniques can be combined with spectroscopy at high resolutions, owing to experimental time limitations the resulting fields of view are too small to be representative of a composite sample. Here a new X‐ray imaging set‐up is proposed, combining full‐field transmission X‐ray microscopy (TXM) with X‐ray absorption near‐edge structure (XANES) spectroscopy to follow two‐dimensional and three‐dimensional morphological and chemical changes in large volumes at high resolution (tens of nanometers). TXM XANES imaging offers chemical speciation at the nanoscale in thick samples (>20 µm) with minimal preparation requirements. Further, its high throughput allows the analysis of large areas (up to millimeters) in minutes to a few hours. Proof of concept is provided using battery electrodes, although its versatility will lead to impact in a number of diverse research fields. 相似文献
78.
79.
Jolly Andrews Vincent Mathew 《Physica C: Superconductivity and its Applications》2011,471(11-12):338-343
A high transition temperature superconducting microstrip structure is modeled using the theoretical approach developed by Coffey and Clem for elucidating the vortex effects in propagation. Impedance type Green’s functions are derived for the electric field around the strip and the propagation characteristics are computed for a wide range of applied field, reduced temperature and superconducting strip thickness in a Galerkin procedure. The increase of static field and temperature result in increased vortex motion, which in turn, causes a corresponding change in the propagation characteristics of the transmission line. Numerical results are presented for propagation parameters and quality factor. 相似文献
80.
Received May 28, 1996 / Revised version received May 1, 1998 Published online October 9, 1998 相似文献