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31.
We prove a general optimal Lp-Euclidean logarithmic Sobolev inequality by using Prékopa-Leindler inequality and a special Hamilton-Jacobi equation. In particular we generalize the inequality proved by Del Pino and Dolbeault in (J. Funt. Anal.).  相似文献   
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The purpose of this work is to present a model for 3D massive gravity with topological and higher-derivative terms. Causality and unitarity are discussed at tree-level. Power-counting renormalizability is also contemplated.  相似文献   
34.
We study the long time asymptotics of a nonlinear, nonlocal equation used in the modelling of granular media. We prove a uniform exponential convergence to equilibrium for degenerately convex and nonconvex interaction or confinement potentials, improving in particular results by J. A. Carrillo, R. J. McCann and C. Villani. The method is based on studying the dissipation of the Wasserstein distance between a solution and the steady state.  相似文献   
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36.
The thermal behaviour of Na3 [Fe(CN)5SO(CH3)2] · 2H2O has been investigated by thermogravimetry and diferential thermal analysis. The results are briefly discussed.  相似文献   
37.
The quality of the determination of compound-specific isotopic content at natural abundance by gas chromatography–isotope ratio measurement–mass spectrometry (GC-irm-MS) relies on the stability of the voltage generated by the ion detector Faraday cages. The application of GC-irm-MS to the determination of δ13C (‰) and δ15N (‰) is now routine. However, for numerous applications, it is necessary to determine both the isotope content (δ15N) and the quantity (in micromoles) of analyte present. We now show that it is possible for nitrogen-containing compounds to measure how much analyte is present with an irm mass spectrometer linked to a GC by exploiting the integrated N2 total ion current intensity (Vs) generated by measuring the 15N/14N isotope ratio. The method is validated over a range of concentration (2–70 mmol/L) and δ15N (−70 to +50‰) values for six molecules of diverse chemical nature and functionality (nortropine, norpseudotropine, nortropinone, cysteine, taurine, glutathione). It is shown that once the ion current is calibrated, the quantitative values are of a comparable quality to those obtained from GC with flame ionization detection (GC-FID). In addition, it is demonstrated that over a definable range, the δ15N (‰) value is independent of the quantity of analyte introduced, confirming the validity of this method.  相似文献   
38.
We describe here a simple and catalyst-free method to synthesize diaryl selenides by reaction of arenediazonium tetrafluoroborate salts with arylselenols, generated in situ by using diaryl diselenides and hypophosphorous acid (H3PO2), using THF as solvent. This is a direct nucleophilic aromatic substitution (SNAr) reaction performed with diaryl diselenides and arenediazonium salts bearing electron-withdrawing and electron-donating groups affording the corresponding diaryl selenides in moderated to good yields.  相似文献   
39.
Bound-constrained minimization is a subject of active research. To assess the performance of existent solvers, numerical evaluations and comparisons are carried on. Arbitrary decisions that may have a crucial effect on the conclusions of numerical experiments are highlighted in the present work. As a result, a?detailed evaluation based on performance profiles is applied to the comparison of bound-constrained minimization solvers. Extensive numerical results are presented and analyzed.  相似文献   
40.
The MnIII/MnII redox couple with a standard potential of +1.51 V versus the standard hydrogen electrode (SHE) has attracted interest for the design of V/Mn redox flow batteries (RFBs). However, MnIII disproportionation leads to a loss of capacity, an increase in pressure drop, and electrode passivation caused by the formation of MnO2 particles during battery cycling. In this work, the influence of TiIV or/and VV on MnIII stability in acidic conditions is studied by formulating four different electrolytes in equimolar ratios (Mn, Mn/Ti, Mn/V, Mn/V/Ti). Voltammetry studies have revealed an ECi process for MnII oxidation responsible for the electrode passivation. SEM and XPS analysis demonstrate that the nature and morphology of the passivating oxides layer depend strongly on the electrolyte composition. Spectroelectrochemistry highlights the stabilization effect of TiIV and VV on MnIII. At a comparable pH, the amount of MnIII loss through disproportionation is decreased by a factor of 2.5 in the presence of TiIV or/and VV. Therefore, VV is an efficient substitute for TiIV to stabilize the MnIII electrolyte for RFB applications.  相似文献   
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