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101.
Alexander J Artuso M Bebek C Berkelman K Browder T Cassel DG Cheu E Coffman DM Crawford G DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Katayama N Kreinick DL Lewis JD Ludwig GS Mistry NB Mueller J Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Selen M Silverman A Stone S Worden H Worris M Sadoff AJ Avery P Besson D Garren L Yelton J Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Zhu Y 《Physical review letters》1990,65(13):1531-1534
102.
Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Ammar R Baringer P Coppage D Haas P Lam H Jawahery A Park CH Kubota Y Nelson JK Perticone D Poling R Chen W Dominick J McIlwain RL Miller DH Ng CR Schaffner SF Shibata EI Yao W Sparks K Thorndike EH Alam MS Kim IJ Li WC Lou XC Sun CR Fulton R Hempstead M Jensen T Johnson DR Kagan H Kass R Morrow F Whitmore J Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Alexander J 《Physical review D: Particles and fields》1990,41(3):805-808
103.
1,3-Diphenyl-5-imino-2-imidazolidinone-4-thione (II) was treated with diazomethanes to give (III-V). Interaction of (II) with amino compounds furnished the corresponding 4-substituted imino derivatives (VIa-m). Imidazoquinoxaline derivatives (VIIIb, c) were obtained through interaction of (II) with o-phenylenediamines. Condensation of (II) with hydrazines afforded the hydrazones (IX, Xa, b). Semicarbazone and thiosemicarbazone derivatives (XIIa-d) were prepared from the reaction of (IX) with isocyanates and isothiocyanates. Again (II) was allowed to react with n-butylmagnesium bromide and HgCl2 to give (XIII) and (XIV) respectively. 相似文献
104.
A. S. Shalabi M. A. Kamel H. Y. Ammar 《International journal of quantum chemistry》2005,103(4):432-448
The FA1:Cs+ and FA2:Li+ color centers at the low coordination (100) and (110) surfaces of AgCl and AgBr play important roles in laser light generation and color image formation. Double‐well potentials at these surfaces are investigated by using ab initio calculations. Quantum clusters were embedded in the simulated Coulomb fields that closely approximate the Madelung fields of the host surfaces, and ions that are the nearest neighbors to the FA ? defect site are allowed to relax to equilibrium. The calculated Stokes shifts suggest that laser light generation is sensitive to the simultaneous effects of the vibrational coupling mode, the impurity cation, the coordination number of the surface ion, the lattice anion, and the choice of the basis set centered on the anion vacancy. An attempt has been made to explain these effects in terms of Madelung potential, electron affinity, and optical–optical conversion efficiency. All relaxed excited states of the defect‐containing surfaces are deep below the lower edges of the conduction bands of the ground‐state defect‐free surfaces, suggesting that the FA(I):Cs+ and FA(II):Li+ centers are suitable laser defects. The dependence of orientational destruction, recording sensitivity, and exciton (energy) transfer on the empty cation; the coordination number of the surface ion; and the lattice anion is clarified. The Glasner–Tompkins empirical rule was generalized to include the impurity cation and the coordination number of the surface ion. As far as color image formation is concerned, the supersensitizer was found to increase the sensitizing capabilities of two primary dyes in the excited states by increasing the relative yield of quantum efficiency. The (110) surfaces of AgBr and AgCl were more sensitive than the corresponding (100) surfaces, and AgBr thin film was found to be more sensitive than that of AgCl. On the basis of quasi‐Fermi levels, the difference in the sensitizing capabilities between the examined dyes in the excited states is determined. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
105.
An automated, sheathless capillary electrophoresis-mass spectrometry platform for discovery of biomarkers in human serum 总被引:1,自引:0,他引:1
Sassi AP Andel F Bitter HM Brown MP Chapman RG Espiritu J Greenquist AC Guyon I Horchi-Alegre M Stults KL Wainright A Heller JC Stults JT 《Electrophoresis》2005,26(7-8):1500-1512
A capillary electrophoresis-mass spectrometry (CE-MS) method has been developed to perform routine, automated analysis of low-molecular-weight peptides in human serum. The method incorporates transient isotachophoresis for in-line preconcentration and a sheathless electrospray interface. To evaluate the performance of the method and demonstrate the utility of the approach, an experiment was designed in which peptides were added to sera from individuals at each of two different concentrations, artificially creating two groups of samples. The CE-MS data from the serum samples were divided into separate training and test sets. A pattern-recognition/feature-selection algorithm based on support vector machines was used to select the mass-to-charge (m/z) values from the training set data that distinguished the two groups of samples from each other. The added peptides were identified correctly as the distinguishing features, and pattern recognition based on these peptides was used to assign each sample in the independent test set to its respective group. A twofold difference in peptide concentration could be detected with statistical significance (p-value < 0.0001). The accuracy of the assignment was 95%, demonstrating the utility of this technique for the discovery of patterns of biomarkers in serum. 相似文献
106.
We report on measurements of periodic and chaotic self-pulsing beyond the second threshold of far-infrared NH3 lasers. While the instabilities of the 81 m14NH3 laser follow a simple pattern, for the 374 m15NH3 laser different pulsing properties are found in different parameter ranges.Pulses under conditions of high pumping power are measured in detail, in view of possible applications of these coherent, high-repetition rate far-infrared pulsed lasers. 相似文献
107.
108.
109.
Mohamed B. H. Sassi M’hamed Boutaous 《Journal of Thermal Analysis and Calorimetry》2014,117(2):943-951
The hot wire technique is widely used to determine the thermal properties of materials. Commonly, this technique is developed for considered infinite radius of cylindrical mediums. Here, we propose an analytical solution of the heat conduction problem in an insulated finite sample. The derived temperature solution is found mathematically to be non-regular convergent series, and lead to avoid the assumption of infinite geometries, difficult to realize in practice. The first part of this paper concerns the study of the calculability of this series. The second one deals with the thermal properties estimation. The sensitivity study shows that the estimation procedure is feasible either using the concept of the time of the maximum rising temperature or, when exploring large time measurements, using the least squares minimisation that has an equivalent pure graphical procedure. 相似文献
110.
Sami H. Mahmood Jumana Dawood Abdel-Fatah Lehlooh Abdelwaheb Cheikhrouhou Abdallah Ammar 《Hyperfine Interactions》2010,196(1-3):385-394
In this work we report the results of X-ray diffraction and Mössbauer spectroscopy for the systems Pr0.5Sr0.5Mn1???x Fe x O3 (with x?=?0.05, 0.10, 0.15, 0.20, 0.25, 0.30). XRD patterns indicated that all samples were single phase with slightly distorted orthorhombic symmetry. Room temperature Mössbauer spectra are all quadrupole split, indicating paramagnetic relaxation of the Fe moment for all values of Fe concentrations. The spectra are fitted with two doublet components associated with Fe3?+? ions in octahedral sites with different distortions. Mössbauer spectra recorded at liquid nitrogen temperature for this system also indicate paramagnetic relaxation of the Fe moments down to liquid nitrogen temperature (LNT). In these spectra a third quadrupole component with quadrupole splitting close to zero develops. This component is associated with the delocalization of the charge carriers and the consequent disappearance of lattice distortions produced by the polaronic effect at room temperature. The component with the high quadrupole splitting (0.81 to 1.07 mm/s) results from Jahn–Teller distortion as a consequence of charge ordering transition at low temperature. 相似文献