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51.
Belz J Cousins RD Diwan MV Eckhause M Ecklund KM Hancock AD Highland VL Hoff C Hoffmann GW Irwin GM Kane JR Kettell SH Klein JR Kuang Y Lang K Martin R May M McDonough J Molzon WR Riley PJ Ritchie JL Schwartz AJ Trandafir A Ware B Welsh RE White SN Witkowski MT Wojcicki SG Worm S 《Physical review letters》1996,76(18):3277-3280
52.
1引言我们知道,一个可生成L2(R)中的多分辩分析的尺度函数(x)满足双尺度差分方程(1)式的Fourier变换为其中(ω)是函数(x)的Fourier变换,而叫做小波的共轭滤波器(简称滤波器),它满足若将滤波器H(ω)设成则条件(3)成为可形式地写出Daubechies[1]给出了(6)式无穷乘积收敛的条件.她还针对F(z)为多项式情形(此时称滤波器为多项式滤波器),给出了产生紧支小波的方法并给出了正则阶估计[2].在[3]中,作者给出了小波分式滤波器的定义(即(4)式中F(z))是实系数有理… 相似文献
53.
A theoretical investigation is reported of the fine structure levels and the spin-singlet contributions to zero-field-splitting (ZFS) parameters for Cr2+ ion in CdGa2S4 crystals. Firstly, the complete energy matrix including all spin states for a 3d 4 ion in tetrahedral D 2d symmetry is constructed according the double-group chain in the strong-field scheme. Then, by diagonalizing the complete energy of electron–electron interactions, the crystal field and the spin–orbit coupling for the Cr2+ (3d 4) ion in CdGa2S4 crystal, the fine structure levels and the spin-singlet contributions to ZFS parameters a, D and F are calculated. The results show that the spin-singlet contribution to D is negligible, but the contributions to a and F are very important. So, to obtain more accurate ZFS parameters for 3d 4 ions in the tetrahedral crystals, all spin states should be considered. 相似文献
54.
本文给出数值方法解Volterra积分方程的稳定性分析,我们判定可约积分方法的数值稳定性基于如下试验方程其中τ是正常数,p和q是复值的。在上述试验方程的情况下,我们研究θ-方法及可约积分方法的稳定性。 相似文献
55.
This paper focuses on the numerical stability of the block θ-methods adapted to differential equations with a dday argument. For the block θ-methods, an interpolation procedure is introduced which leads to the mumerical processes that satisfy an important asymptotic stability condition related to the class of test problems y' (t)=ay(t)+by(t-r) with a,b∈C, Re(a)<- |b| and τ>0. We prove that the block θ-method is GP-stable if and only if the method is A-stable for ordinary differential equations. Furthermore, it is proved that the P-and GP-stability are equivalent for the block θ-method. 相似文献
56.
Based on the theories of nonlinear continuum mechanics, piezoelectricity and elastic waves in solids, theoretical analysis of Bleustein-Gulyaev surface acoustic wave propagation in a prestressed layered piezoelectric structure are described. Numerical calculations are performed for the case that the layer and the substrate are identical LiNbO(3) except that they are polarized in opposite directions. It is found that an almost linear behavior of the relative change in phase velocity versus the initial stress is obtained for both surface electrically free and shorted cases. Potential applications in the design of acoustic wave devices are suggested. 相似文献
57.
We propose a scheme to engineer a non-local two-qubit
phase gate between two remote quantum-dot spins. Along with
one-qubit local operations, one can in principal perform various
types of distributed quantum information processing. The scheme
employs a photon with linearly polarisation interacting one after
the other with two remote quantum-dot spins in cavities. Due to the
optical spin selection rule, the photon obtains a Faraday rotation
after the interaction process. By measuring the polarisation of the
final output photon, a non-local two-qubit phase gate between the
two remote quantum-dot spins is constituted. Our scheme may has very
important applications in the distributed quantum information
processing. 相似文献
58.
Xiu-Li Kuang Xiao-Mei Zhao Hai-Fang Xu Yuan-Yuan Shi Jin-Bo Deng Guo-Tao Sun 《BMC neuroscience》2010,11(1):137
Background
Neuron-derived neurotrophic factor (NDNF) is evolutionarily well conserved, being present in invertebrate animals such as the nematode, Caenorhabditis elegans, as well as in the fruit fly, Drosophila melanogaster. Multiple cysteines are conserved between species and secondary structure prediction shows that NDNF is mainly composed of beta-strands. In this study, we aimed to investigate the function of NDNF. 相似文献59.
60.
Equilibrium geometries, relative stabilities, and magnetic properties of small AunMn (n=1-8) clusters have been investigated using density functional theory at the PW91P86 level. It is found that Mn atoms in the ground state AunMn isomers tend to occupy the most highly coordinated position and the lowest energy structure of AunMn clusters with even n is similar to that of pure Aun+1 clusters, except for n=2. The substitution of Au atom in Aun+1 cluster by a Mn atom improves the stability of the host clusters. Maximum peaks are observed for AunMn clusters at n=2, 4 on the size dependence of second-order energy differences and fragmentation energies, implying that the two clusters possess relatively higher stability. The HOMO-LUMO energy gaps of the ground state AunMn clusters show a pronounced odd-even oscillation with the number of Au atoms, and the energy gap of Au2Mn cluster is the biggest among all the clusters. The magnetism calculations indicate that the total magnetic moment of AunMn cluster, which has a very large magnetic moment in comparison to the pure Aun+1 cluster, is mainly localized on Mn atom. 相似文献