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991.
When the oblique incidence interferometry is used to measure the form deviation of the tooth flank, because of the anamorphic distortion and image foreshortening, the collected interference fringe pattern (IFP) cannot be positioned on the tooth flank directly. Therefore a simulation tooth image (STI) is employed as a bridge to connect the collected IFP and the tooth flank. The exiting method is good enough to deal with the IFP of spur gear tooth flank, but it is inappropriate for the IFP of helical gear. This paper focuses on two improvements for positioning the IFP of helical gear on the tooth flank: (1) in the process of generating the STI, a mathematical model of helical tooth flank is proposed to judge the shielded situation of tooth flank; (2) in the process of matching the STI with the collected IFP, a non-rigid matching method is proposed to determine the relationship of the two images. The results of an experimental application are given to verify the feasibility and accuracy. 相似文献
992.
On the basis of the Wilsonian renormalization group (WRG) analysis of nuclear effective field theory (NEFT) including pions, we propose a practical calculational scheme in which the short-distance part of one-pion exchange (S-OPE) is removed and represented as contact terms. The long-distance part of one-pion exchange (L-OPE) is treated as perturbation. The use of dimensional regularization (DR) for diagrams consisting only of contact interactions considerably simplifies the calculation of scattering amplitude and the renormalization group equations. NLO results for nucleon-nucleon elastic scattering in the S-waves are obtained and compared with experiments. A brief comment on NNLO calculations is given. 相似文献
993.
Polycarbonates (4a–d) with various side chain lengths were synthesized by the reaction of 1,4-bis(hydroxyethoxy)benzene derivatives and triphosgene in the presence of pyridine. The polymer electrolytes composed of 4a–d with lithium bis(trifluoromethanesulfonyl)imide (LiN(SO2CF3)2, LiTFSI) were prepared, and their ionic conductivities and thermal and electrochemical properties were investigated. 4d-Based polymer electrolyte showed the highest ionic conductivity values of 1.0?×?10?4?S/cm at 80 °C and 1.5?×?10?6?S/cm at 30 °C, respectively, at the [LiTFSI]/[repeating unit] ratio of 1/2. Ionic conductivities of these polycarbonate-based polymer electrolytes showed the tendency of increase with increasing the chain length of oxyethylene moieties as side chains, suggestive of increased steric hindrance by side chains. Unique properties were observed for the 4a(n?=?0)-based polymer electrolyte without an oxyethylene moiety. All of polycarbonate-based polymer electrolytes showed good electrochemical and thermal stabilities as polymer electrolytes for battery application. 相似文献
994.
We review recent developments in the physics of ultracold atomic and molecular gases in optical lattices. Such systems are nearly perfect realisations of various kinds of Hubbard models, and as such may very well serve to mimic condensed matter phenomena. We show how these systems may be employed as quantum simulators to answer some challenging open questions of condensed matter, and even high energy physics. After a short presentation of the models and the methods of treatment of such systems, we discuss in detail, which challenges of condensed matter physics can be addressed with (i) disordered ultracold lattice gases, (ii) frustrated ultracold gases, (iii) spinor lattice gases, (iv) lattice gases in “artificial” magnetic fields, and, last but not least, (v) quantum information processing in lattice gases. For completeness, also some recent progress related to the above topics with trapped cold gases will be discussed.
Motto: 相似文献
995.
Generalized Weyl quantization formalism for the cylindrical phase space S1×R1 is developed. It is shown that the quantum observables relevant to the phase of the linear harmonic oscillator or electromagnetic field can be represented within this formalism by the self-adjoint operators on the Hilbert space L2(S1). 相似文献
996.
This paper presents the general theory of canonical transformations of coordinates in quantum mechanics. First, the theory is developed in the formalism of phase space quantum mechanics. It is shown that by transforming a star-product, when passing to a new coordinate system, observables and states transform as in classical mechanics, i.e., by composing them with a transformation of coordinates. Then the developed formalism of coordinate transformations is transferred to a standard formulation of quantum mechanics. In addition, the developed theory is illustrated on examples of particular classes of quantum canonical transformations. 相似文献
997.
Y. Yamada Y. Kobayashi M. K. Kubo M. Mihara T. Nagatomo W. Sato J. Miyazaki S. Sato A. Kitagawa 《Hyperfine Interactions》2014,226(1-3):35-40
The in-beam Mössbauer spectrum of 57Mn implanted into a Xe solid at 14 K was measured. Four singlets were observed in the spectrum, assigned to 57Fe?+? (3d7), 57Fe?+? (3d64s1), 57Fe0 (3d64s2), and 57Fe0 (3d74s1). The assignments were in agreement with calculated electron densities at nuclei reported in the literature. The β-decay of 57Mn did not disturb the surrounding Xe lattice, showing a singlet peak, and the excited states were stabilized in the time range of the Mössbauer measurements of ~100 ns. The production mechanism was explained in terms of the reduction of 57Mn x?+? and 57Fe y?+? ions by free electrons in the Xe matrix. 相似文献
998.
Y. Kobayashi M. Mihara T. Nagatomo Y. Yamada M. K. Kubo J. Miyazaki W. Sato S. Sato A. Kitagawa 《Hyperfine Interactions》2014,226(1-3):679-685
A new detector system for the coincidence technique between Mössbauer γ-rays and energetic β-rays originating from 57Mn has been developed for in-beam Mössbauer spectroscopy using 57Mn implantation. This system enables time-resolved Mössbauer measurements of 57Fe at various elapsed times after β ?-decay of 57Mn with sufficient quality. We applied this system to the time-dependent measurement of the site distributions of dilute Fe atoms in n-type Si. It was suggested that Fe atoms were already located at substitutional and interstitial positions in Si within a time of about 100 ns after the β ?-decay of 57Mn, and that the occupancy ratio between these positions was hardly dependent on the elapsed time after the β ?-decay. 相似文献
999.
We investigate the role of the central two-body nucleon-nucleon correlations on typical quantities observed in relativistic
heavy-ion collisions. Basic correlation measures, such as the fluctuations of the participant eccentricity, initial size fluctuations,
or the fluctuations of the number of sources producing particles, are sensitive at the level 10–20% to the inclusion of the
two-body correlations. However, the realistic correlation function gives virtually indistinguishable results from the hard-core repulsion with the expulsion distance set to ∼0.9 fm. In the second part of the talk we compare the spherical and Gaussian wounding
profiles and find that the latter, which is more realistic, leads to reduced eccentricity and fluctuations. This has significance
for precision studies of the elliptic flow. 相似文献
1000.
Harry Alles Jaan Aarik Aleks Aidla Aurelien Fay Jekaterina Kozlova Ahti Niilisk Martti Pärs Mihkel Rähn Maciej Wiesner Pertti Hakonen Väino Sammelselg 《Central European Journal of Physics》2011,9(2):319-324
Atomic layer deposition of HfO2 on unmodified graphene from HfCl4 and H2O was investigated. Surface RMS roughness down to 0.5 nm was obtained for amorphous, 30 nm thick hafnia film grown at 180°C. HfO2 was also deposited in a two-step temperature process where the initial growth of about 1 nm at 170°C was continued up to 10–30 nm at 300°C. This process yielded uniform, monoclinic HfO2 films with RMS roughness of 1.7 nm for 10–12 nm thick films and 2.5 nm for 30 nm thick films. Raman spectroscopy studies revealed that the deposition process caused compressive biaxial strain in graphene, whereas no extra defects were generated. An 11 nm thick HfO2 film deposited onto bilayer graphene reduced the electron mobility by less than 10% at the Dirac point and by 30–40% far away from it. 相似文献