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991.
We establish conditions under which K-spaces in the limiting real interpolation involving slowly varying functions can be described by means of J-spaces and we also solve the reverse problem. To this end, we prove several versions of the fundamental lemma of the real interpolation theory. We apply our results to obtain density theorems for the corresponding limiting interpolation spaces. 相似文献
992.
Gary L. Cloud 《Experimental Mechanics》1980,20(1):9-16
Residual strains near coldworked holes were measured for several degrees of radial expansion. Moiré-grating photography created magnified replicas of deformed gratings. Fringe patterns with sensitivity multiplication and S/N improvement were obtained by optical data processing and by using slotted apertures for photography. Computer data reduction and plotting provided the required strain maps. 相似文献
993.
Comparison of the three-phase oil relative permeability models 总被引:3,自引:0,他引:3
A comparative study of seven different methods for predicting three-phase oil relative permeabilities in the presence of gas and water phases is presented. Predicted oil relative permeabilities from these correlations have been compared with published three-phase experimental data obtained in Berea sandstone core samples. Some of the correlations under study have been recently developed and have never been tested against the laboratory data.The comparison shows that the commonly used models such as Stones' often do not give accurate predictions of the experimental data. It is concluded that the recently developed models fit the experimental data as well as or better than the previously developed and widely used three-phase oil relative permeability models. 相似文献
994.
We present an effective approach for modelling compositional data with large concentrations of zeros and several levels of variation, applied to a database of elemental compositions of forensic glass of various use types. The procedure consists of the following: (i) partitioning the data set in subsets characterised by the same pattern of presence/absence of chemical elements and (ii) fitting a Bayesian hierarchical model to the transformed compositions in each data subset. We derive expressions for the posterior predictive probability that newly observed fragments of glass are of a certain use type and for computing the evidential value of glass fragments relating to two competing propositions about their source. The model is assessed using cross‐validation, and it performs well in both the classification and evidence evaluation tasks. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
995.
Gary S. Nichol Ruben Vardanyan Victor J. Hruby 《Journal of chemical crystallography》2010,40(11):961-964
Abstract
As part of a study into new Fentanyl-derived opioid compounds with potent analgesic activity and reduced side effects the starting material title compound, C14H21N3O (1), was synthesized and characterized by NMR spectroscopy and single-crystal X-ray diffraction. The crystal structure is monoclinic Cc with unit cell parameters a = 14.1480(3) ?, b = 14.1720(4) ?, c = 27.6701(7) ?, β = 96.956(1)°, α = γ = 90°. The compound has crystallized with four crystallographically unique molecules in the asymmetric unit; each molecule has a very similar conformation and an analysis of the structure shows that although all four unique molecules overlay very well there is no evidence of pseudo-symmetry which would relate the molecules in the higher symmetry space group C2/c. The crystal packing consists of two separate hydrogen bonded chains which are linked together to form a thick 2D structure in the ab plane. 相似文献996.
Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is used for the first time to characterize radio frequency plasma-deposited polymers and for investigation of the plasma polymerization process. The MALDI mass spectra of the plasma polymers of allyl alcohol, di(ethylene glycol) vinyl ether and ethylene glycol butyl vinyl ether are all reported using solvent-based MALDI sample preparation approaches. The MALDI mass spectra of each of the three plasma polymers contain distinctive polymer series ion signals having molecular weight distributions below 2000 Da. Unexpectedly, however, the ion signals from each of the three plasma polymers show a common polymer repeat unit of 44 Da, for which the chemical formula is most likely -(C(2)H(4)O)-, and no evidence of the expected radical chain polymerization polymer is detected. These results are discussed in terms of the likely involvement of gas-phase radical species having different stabilities in the radio frequency plasma environment. 相似文献
997.
Wojciechowski J Chase-Baldwin K Wasieloski LP Padilla S Vora GJ Taitt CR 《Analytica chimica acta》2010,679(1-2):85-90
Microarray performance depends upon the ability to screen samples against a vast array of probes with the appropriate sensitivity and selectivity. While these factors are significantly influenced by probe design, they are also subject to the particular detection methodology and reagents employed. Herein we describe the incorporation of super avidin-biotin system (SABS) and secondary enzymatic enhancement (SEE) as post-hybridization signal amplification techniques to improve the sensitivity of oligonucleotide microarrays. To these ends, we tested these methods on electrochemically interrogated arrays using both purified influenza A PCR products and randomly amplified genomic Francisella tularensis DNA as targets. While SABS treatment did not improve sensitivity for CombiMatrix ElectraSense(?) arrays using purified influenza A cDNA, chip sensitivity was improved 10-fold for randomly amplified targets. SEE improved performance to a greater degree and was able to lower the detection limits 10-fold for influenza A and 100-fold for F. tularensis DNA. These results indicate the promising capability of post-hybridization amplification techniques for enhancing microarray performance. 相似文献
998.
Brian D. Lawrence Scott Wharram Jonathan A. Kluge Gary G. Leisk Fiorenzo G. Omenetto Mark I. Rosenblatt David L. Kaplan 《Macromolecular bioscience》2010,10(4):393-403
Effects of hydration on silk fibroin film properties were investigated for water‐annealed and MeOH‐treated samples. Hydration increased thickness by 60% for MeOH‐immersed films, while water‐annealed samples remained constant. MeOH‐immersed films showed an 80% mass loss due to water, while water‐annealed lost only 40%. O2 permeability was higher in MeOH‐immersed films with Dk values of 10?10 (mL O2 · cm) · (cm?1 · s?1 · mmHg?1), while those of water‐annealed films reached only one fifth of this value. All films showed a decrease in Young's modulus and increased plastic deformation by two orders of magnitude when submerged in saline solution. FT‐IR showed that β‐sheet content in water‐annealed films increased with increasing water vapor pressure, while MeOH‐immersed films showed no change.
999.
We present the performance limits on three-dimensional (3D) localization accuracy of currently used methods of wide-field superlocalization microscopy. The three methods investigated are double-helix microscopy, astigmatic imaging, and biplane detection. In the shot-noise limit, Cramer-Rao lower bound calculations show that, among these techniques, the double-helix microscope exhibits the best axial and 3D localization accuracy over short as well as long depth-of-field systems. The fundamental advantage of engineered point-spread function systems, like the double-helix, stems from the additional degrees of freedom available to control diffraction in three dimensions over variable regions of interest. 相似文献
1000.
G. Asher Newsome Gary L. Glish 《Journal of the American Society for Mass Spectrometry》2009,20(6):1127-1131
A focused laser is used to make infrared multiphoton photodissociation (IRMPD) more efficient in a quadrupole ion trap mass
spectrometer. Efficient (up to 100%) dissociation at the standard operating pressure of 1 × 10−3 Torr can be achieved without any supplemental ion activation and with shorter irradiation times. The axial amplitudes of
trapped ion clouds are measured using laser tomography. Laser flux on the ion cloud is increased six times by focusing the
laser so that the beam waist approximates the ion cloud size. Unmodified peptide ions from 200 Da to 3 kDa are completely
dissociated in 2.5–10 ms at a bath gas pressure of 3.3 × 10−4 Torr and in 3–25 ms at 1.0 × 10−3 Torr. Sequential dissociation of product ions is increased by focusing the laser and by operating at an increased bath gas
pressure to minimize the size of the ion cloud. 相似文献