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991.
We prove existence of solutions of a two-compressible (liquid and gas) phase flow model in porous media with two components
(water and hydrogen). This model is obtained by writing the mass conservation for each component in each phase. We suppose that the mass exchange between dissolved hydrogen and hydrogen in the gas phase
is supposed finite. This mass exchange is modeled by a source term on each mass conservation equations. 相似文献
992.
Florian Luca 《Archiv der Mathematik》2012,98(3):235-240
Let p(n) be the function that counts the number of partitions of n. Let b ≥ 2 be a fixed positive integer. In this paper, we show that for almost all n the sum of the digits of p(n) in base b is at least log n/(7log log n). Our proof uses the first term of Rademacher’s formula for p(n). 相似文献
993.
994.
995.
We consider direct diphoton production in hadron collisions, and we compute the next-to-next-to-leading order QCD radiative corrections at the fully differential level. Our calculation uses the q(T) subtraction formalism, and it is implemented in a parton-level Monte Carlo program. The program allows the user to apply arbitrary kinematical cuts on the final-state photons and the associated jet activity and to compute the corresponding distributions in the form of bin histograms. We present selected numerical results related to Higgs boson searches at the LHC and corresponding results at the Tevatron. 相似文献
996.
Daranciang D Highland MJ Wen H Young SM Brandt NC Hwang HY Vattilana M Nicoul M Quirin F Goodfellow J Qi T Grinberg I Fritz DM Cammarata M Zhu D Lemke HT Walko DA Dufresne EM Li Y Larsson J Reis DA Sokolowski-Tinten K Nelson KA Rappe AM Fuoss PH Stephenson GB Lindenberg AM 《Physical review letters》2012,108(8):087601
We show that light drives large-amplitude structural changes in thin films of the prototypical ferroelectric PbTiO3 via direct coupling to its intrinsic photovoltaic response. Using time-resolved x-ray scattering to visualize atomic displacements on femtosecond time scales, photoinduced changes in the unit-cell tetragonality are observed. These are driven by the motion of photogenerated free charges within the ferroelectric and can be simply explained by a model including both shift and screening currents, associated with the displacement of electrons first antiparallel to and then parallel to the ferroelectric polarization direction. 相似文献
997.
We construct deformations of general relativity that are consistent and phenomenologically viable, since they respect, in particular, cosmological backgrounds. These deformations have unique symmetries in accordance with their Minkowski cousins (Fierz-Pauli theory for massive gravitons) and incorporate a background curvature induced self-stabilizing mechanism. Self-stabilization is essential in order to guarantee hyperbolic evolution in and unitarity of the covariantized theory, as well as the deformation's uniqueness. We show that the deformation's parameter space contains islands of absolute stability that are persistent through the entire cosmic evolution. 相似文献
998.
Oberacher H Pitterl F Siapi E Steele BR Letzel T Grosse S Poschner B Tagliaro F Gottardo R Chacko SA Josephs JL 《Journal of mass spectrometry : JMS》2012,47(2):263-270
Mass spectral libraries represent versatile tools for the identification of small bioorganic molecules. Libraries based on electron impact spectra are rated robust and transferable. Tandem mass spectral libraries are often considered to work properly only on the instrument that has been used to build the library. An exception from that rule is the 'Wiley Registry of Tandem Mass Spectral Data, MSforID'. In various studies with data sets from different kinds of tandem mass spectrometric instruments, the outstanding sensitivity and robustness of this tandem mass spectral library search approach was demonstrated. The instrumental platforms tested, however, mainly included various tandem-in-space instruments. Herein, the results of a multicenter study with a focus on upfront and tandem-in-time fragmentation are presented. Five laboratories participated and provided fragment ion mass spectra from the following types of mass spectrometers: time-of-flight (TOF), quadrupole-hexapole-TOF, linear ion trap (LIT), 3-D ion trap and LIT-Orbitrap. A total number of 1231 fragment ion mass spectra were collected from 20 test compounds (amiloride, buphenin, cinchocaine, cyclizine, desipramine, dihydroergotamine, dyxirazine, dosulepin, ergotamine, ethambutol, etofylline, mefruside, metoclopramide, phenazone, phentermine, phenytoin, sulfamethoxazole, sulfamoxole, sulthiame and tetracycline) on seven electrospray ionization instruments using 18 different instrumental configurations for fragmentation. For 1222 spectra (99.3%), the correct compound was retrieved as the best matching compound. Classified matches (matches with 'relative average match probability' >40.0) were obtained for 1207 spectra (98.1%). This high percentage of correct identifications clearly supports the hypothesis that the tandem mass spectral library approach tested is a robust and universal identification tool. 相似文献
999.
We discuss the implementation of the “minimal” type III seesaw model, i.e. with one fermionic triplet, in FeynRules/MadGraph.
This is the first step in order to realize a real study of LHC data recorded in the LHC detectors. With this goal in mind,
we comment on the possibility of discovering this kind of new physics at the LHC running at 7 TeV with a luminosity of few
fb−1. 相似文献
1000.
Large eddy simulations of turbulent flow between shrouded co-rotating disks, representing a simplified model of a hard disk drive, are performed. The computation domain surrounds a complete disk and is bounded at top and bottom by half a disk. Therefore, it is possible to compute the fluctuating pressure field surrounding the middle disk. Also, the influence of the shroud geometry is taken into account by comparing a flat shroud wall and a wall with rib chambers. In the flat shroud case, the fluctuating pressure on the upper- and lower-surface of a disk indicates a strong correlation with fluid motion travelling across the disk-tip clearance region. However, in the ribbed shroud case the organized flow structure that is observed in the flat shroud case disappears and the fluctuating pressure acting on the surface of the disk is remarkably diminished. 相似文献