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71.
Prof. Shinji Toyota Dr. Eiji Tsurumaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):6878-6890
Saturn-like systems consisting of nanoscale rings and spheres are fascinating motifs in supramolecular chemistry. Several ring molecules are known to include spherical molecules at the center of the cavity via noncovalent attractive interactions. In this Minireview, we generalize the molecular design, the structural features, and the supramolecular chemistry of such “nano-Saturns”, which consist of monocyclic rings and fullerene spheres (mainly C60), on the basis of previous experimental and theoretical studies. Ring molecules are classified into three types (loop, belt, and disk) according to their shapes and possible interactions. Whereas typical belt-shaped rings tend to form tight complexes due to the wide contact area via π–π interactions, flat disk-shaped rings generally form weak complexes due to the narrow contact area mainly via CH–π interactions. In spite of the small association energies, disk-shaped rings are attractive because such rings can mimic the planet Saturn precisely as exemplified by an anthracene cyclic hexamer–C60 complex. 相似文献
72.
73.
This paper reports the first observation of red electroluminescence (EL) in SrGa2S4:Ce, Mn thin film. The EL spectrum consists of single broad emission band having a peak wavelength of 665 nm. The dominant EL decay time was 31 μs. The relationship between the applied voltage and the EL waveform was measured in single insulating thin film electroluminescent (TFEL) devices. An asymmetric EL waveform was observed in SrGa2S4:Ce, Mn TFEL devices under a rectangular applied voltage. The polarity of the EL waveform in these devices was different from the waveform in manganese-activated zinc sulfide ZnS:Mn devices. This indicates that hot holes excite the Mn2+ ions to cause the red EL. 相似文献
74.
Hashi K Shimizu T Goto A Kiyoshi T Matsumoto S Wada H Fujito T Hasegawa K Yoshikawa M Miki T Ito S Hamada M Hayashi S 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,156(2):318-321
We have developed a 920-MHz NMR system and performed the proton NMR measurement of H(2)O and ethylbenzene using the superconducting magnet operating at 21.6 T (920 MHz for proton), which is the highest field produced by a superconducting NMR magnet in the persistent mode. From the NMR measurements, it is verified that both homogeneity and stability of the magnet have a specification sufficient for a high resolution NMR. 相似文献
75.
K. Ikematsu K. Fujii Z. Hioki Y. Sumino T. Takahashi 《The European Physical Journal C - Particles and Fields》2003,29(1):1-10
We developed a new method for the full kinematical reconstruction of the system near its threshold at future linear e
+
e
-
colliders. In the core of the method lies likelihood fitting which is designed to improve measurement accuracies of the kinematical
variables that specify the final states resulting from decays. The improvement is demonstrated by applying this method to a Monte Carlo sample generated with various experimental effects including beamstrahlung, finite acceptance and resolution of the detector
system, etc. In most cases the fit takes a broad non-Gaussian distribution of a given kinematical variable to a nearly Gaussian
shape, thereby justifying phenomenological analyses based on simple Gaussian smearing of the parton-level momenta. The standard
deviations of the resultant distributions of various kinematical variables are given in order to facilitate such phenomenological
analyses. A possible application of the kinematical fitting method and its expected impact are also discussed.
Received: 4 March 2003 / Published online: 23 May 2003
RID="a"
ID="a" e-mail: ikematsu@post.kek.jp
RID="b"
ID="b" e-mail: fujiik@jlcuxf.kek.jp
RID="c"
ID="c" e-mail: hioki@ias.tokushima-u.ac.jp
RID="d"
ID="d" e-mail: sumino@tuhep.phys.tohoku.ac.jp
RID="e"
ID="e" e-mail: tohrut@hiroshima-u.ac.jp 相似文献
76.
Effects of relaxation of occupied band electrons to the ?-hole state through the hybridization between ? and band states are studied based on a detailed model for Ce-monopnictides. The effective 4? level is shifted about 1–2 eV to shallow energy side from the unrenormalized bare level in processes in which the 4? electron is only virtually excited, such as in excitation to the vacant p band states through the p-? mixing. Photoemission spectra show two peaks, one near the Fermi energy and the other about 3 eV below it. The latter is shifted to deep energy side about 0.5–1 eV from the bare level when it lies near the bottom of the valence band. The discrepancy between the 4? level estimated from the low energy phenomena and that from photoemission is resolved. 相似文献
77.
Shinji Adachi Tatsuya Watanabe 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(2):819-833
We are concerned with the uniqueness result of positive solutions for a class of quasilinear elliptic equation arising from plasma physics. We convert a quasilinear elliptic equation into a semilinear one and show the unique existence of positive radial solution for original equation under the suitable conditions on the power of nonlinearity and quasilinearity. We also investigate the non-degeneracy of a positive radial solution for a converted semilinear elliptic equation. 相似文献
78.
Debasish Ghosh Pradip Ghosh Golap Kalita Takuto Noda Chisato Takahashi Masaki Tanemura 《固体物理学:研究快报》2013,7(7):489-492
An efficient cathode material with high transparency (93%) based on conducting polymer poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and single wall carbon nanotubes (SWCNTs) has been developed for the fabrication of highly transparent and flexible field electron emitters (FEE). This kind of material showed superior field emission (FE) performance with very high current density (10–3A/cm2) at very low electric field. The FE performance of the hybrid materials was dramatically improved compared to either SWCNTs and PEDOT:PSS. Thus the hybrid structures of conducting polymer and SWCNTs might be a good choice for use as a cathode material to enhance the FE performance and for potential application in future portable displays. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
79.
Bailly J. L. Caso C. Chiba Y. Dibon H. Epp B. Ferrando A. Fontanelli F. Ganguli S. N. Gémesy T. Gurtu A. Hamatsu R. Hidas P. Hirose T. Hrubec J. Ivanyshenkov Yu. Kageya T. Khalatyan N. Kistenev E. Kita I. Kitamura S. Kubik V. MacNaughton J. Malhotra P. K. Matsumoto S. Mittra I. S. Montanet L. Neuhofer G. Pinter G. Porth P. Raghavan R. Rodrigo T. Singh J. Squarcia S. Takahashi K. Tanaka R. Tikhonova L. A. Trevisan U. Yamagata T. Zholobov G. Zotkin S. A. 《Zeitschrift fur Physik C Particles and Fields》1989,43(3):341-348
Zeitschrift für Physik C Particles and Fields - Correlations among identically charged pions were measured for pions produced inp p collisions at 360 GeV/c using the EHS spectrometer. The... 相似文献
80.
Keiichi Hirano Yoshiki Yamashita Yumiko Takahashi Hiroshi Sugiyama 《Journal of synchrotron radiation》2015,22(4):956-960
A novel X‐ray Bragg optics is proposed for variable‐magnification of an X‐ray beam. This X‐ray Bragg optics is composed of two magnifiers in a crossed arrangement, and the magnification factor, M, is controlled through the azimuth angle of each magnifier. The basic properties of the X‐ray optics such as the magnification factor, image transformation matrix and intrinsic acceptance angle are described based on the dynamical theory of X‐ray diffraction. The feasibility of the variable‐magnification X‐ray Bragg optics was verified at the vertical‐wiggler beamline BL‐14B of the Photon Factory. For X‐ray Bragg magnifiers, Si(220) crystals with an asymmetric angle of 14° were used. The magnification factor was calculated to be tunable between 0.1 and 10.0 at a wavelength of 0.112 nm. At various magnification factors (M≥ 1.0), X‐ray images of a nylon mesh were observed with an air‐cooled X‐ray CCD camera. Image deformation caused by the optics could be corrected by using a 2 × 2 transformation matrix and bilinear interpolation method. Not only absorption‐contrast but also edge‐contrast due to Fresnel diffraction was observed in the magnified images. 相似文献