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381.
In this paper, the path integral solutions for a general n-dimensional stochastic differential equations (SDEs) with -stable Lévy noise are derived and verified. Firstly, the governing equations for the solutions of n-dimensional SDEs under the excitation of -stable Lévy noise are obtained through the characteristic function of stochastic processes. Then, the short-time transition probability density function of the path integral solution is derived based on the Chapman-Kolmogorov-Smoluchowski (CKS) equation and the characteristic function, and its correctness is demonstrated by proving that it satisfies the governing equation of the solution of the SDE, which is also called the Fokker-Planck-Kolmogorov equation. Besides, illustrative examples are numerically considered for highlighting the feasibility of the proposed path integral method, and the pertinent Monte Carlo solution is also calculated to show its correctness and effectiveness. 相似文献
382.
刘红梅;李阳 《数学物理学报(A辑)》2025,45(1):136-152
基于两个3F2-超几何级数求和公式,该文建立了两个一般的双变量级数变换公式.在经典超几何级数求和公式的帮助下,这两个变换公式变形出一系列形如Fq:1;0p:2;1的Kampéde Fériet级数求和公式.另外,利用四个Saalschützian4F3 [1]-求和公式,一些形如Fq:1;1p:2;2的Kampéde Fériet级数的简化和变换公式也被推导出来. 相似文献
383.
本文给出Fréchet空间中集值映射的锥拉伸与锥压缩不动点定理。同时也讨论Banach空间与Hilbert空间中集值映射的相应不动点定理。并导出逼近定理作为应用。 相似文献
384.
385.
A. I. Belogorokhov S. I. Bozhko A. N. Chaika A. M. Ionov S. A. Trophimov V. D. Rumiantseva D. Vyalikh 《Applied Physics A: Materials Science & Processing》2009,94(3):473-476
The main goal of this paper is to investigate the electronic structure of valence band and core levels as well as surface
topography of pristine tetraphenylporphyrin and Pt-based compounds Pt-TPP(p-COOH3)4, Pt-TPP(m-OCH3)4, PtCl2-TPP(m-OCH3)4 thin films. The electronic structure of various Pt-based metalloporphyrins which were investigated in dependence on their
chemical structure and spectra were measured by high-resolution X-ray photoelectron spectroscopy (XPS) of valence band and
Pt4f, Pt4d, C1s, O1s, N1s core levels. Results of atomic force microscopy (AFM) studies of topography and self-assembling
processes in thin films of porphyrines are presented and discussed. 相似文献
386.
Dana M. Alloway Neal R. Armstrong 《Applied Physics A: Materials Science & Processing》2009,95(1):209-218
We present here the characterization of organic/organic′ heterojunctions created from either of two perylene dyes, perylenetetracarboxylicdianhydride
(PTCDA) or the bisimide derivative perylenetetracarboxylicdianhydride-N,N′-bis (butyl)imide (C4-PTCDI), and two chloro-metallated
donor phthalocyanines (ClAlPc or ClInPc). The perylene dyes were selected to create thin films with the core of the perylene
dye parallel to the substrate plane (PTCDA) or nearly vertical to the substrate plane, with layer planes defined by the butyl
substituents (C4-PTCDI). We compare the frontier orbital offsets revealed by UV-photoelectron spectroscopy, and quenching
of luminescence of the perylene dyes, as a function of Pc coverage. The ionization potentials (IPs) of the Pc layers, the
degree to which interface dipoles are formed at the Pc/perylene dye interface, and the degree of quenching of the perylene
luminescence are affected by the structure of the Pc/perylene interface. Pc/PTCDA heterojunctions show significant interface
dipoles and higher IPs for the first-deposited Pc layers compared to Pc/C4-PTCDI heterojunctions, which show negligible interface
dipoles and lower overall IP values for initial Pc layers. Luminescence of the selectively excited perylene layers is quenched
by the addition of even submonolayer coverages of Pc. This quenching process occurs as a result of both energy transfer (perylene
to Pc) and charge transfer (Pc to perylene). Luminescence from monomeric and aggregated ClAlPc and ClInPc monolayers is seen
on C4-PTCDI films, whereas only luminescence from the aggregated forms of these Pcs is seen on PTCDA films. These studies
reveal aspects of organic heterojunction energetics which may have important implications for organic solar cell design. 相似文献
387.
Hiroyuki Yoshida Yuji Watazu Naoki Sato Toshihiro Okamoto Shigehiro Yamaguchi 《Applied Physics A: Materials Science & Processing》2009,95(1):185-191
Ultraviolet photoemission spectroscopic measurements of bis (benzo)pentathienoacene were carried out in gas and solid phase.
For the measurements of solid phase, vacuum deposited films in both amorphous and crystalline phase were prepared on different
substrates of HOPG and polycrystalline Au, respectively. The adiabatic ionization energies were determined to be 6.84, 5.32, and 5.08 eV, for gas, amorphous, and crystalline phases, respectively. The spectral lineshapes were interpreted with the aid of the
density functional calculations for both isolated molecule and single-crystal structure. The calculated electronic structures
were further analyzed in terms of the energy band dispersion and the transport properties of charge carriers. 相似文献
388.
该文讨论了一类由时变Lévy噪声驱动的随机微分方程(LSDE)的平均值原理,提出了其均值化方程,在均方和以概率意义下得到了均值化方程的解收敛到原LSDE的解,给出了一个具体例子. 相似文献
389.
K. Wünstel O. Kumagai P. Wagner W. Jantsch 《Applied Physics A: Materials Science & Processing》1982,27(4):251-256
The influence of hydrostatic pressure up to 5×108 Pa on deep levels related to transition metal impurities in silicon is determined by means of an isothermal capacitance method. Under pressure, donor levels of isolated Fe, V, Ti, and Mn shift towards the valence band in contrast to earlier results for deep chalcogen donors. This behavior is contrary to what is expected by considering only effects of hybridization. Quantitative differences between Fe, Ti, V, and, on the other hand, Mn suggest a different microscopic structure of these defects. The Fe-acceptor pairs FeB, FeAl, and FeGa move towards the valence band with a rate comparable to that of the 1 conduction band. The thermal capture coefficients of isolated Fe, V, and Ti are found to be pressure independent up to 5×108 Pa.On leave from Sony Corp., Research Center, Yokohama, Japan 相似文献
390.