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991.
We consider (anti-)Poisson superalgebras with a constant nondegenerate (anti)bracket realized on smooth Grassmann-valued functions
with compact supports in ℝn and find the deformations of these superalgebras and their central extensions.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 155, No. 1, pp. 109–116, April, 2008. 相似文献
992.
We introduce a super-Lévy process and study maximal speed of all particles process is a measure on the set of paths.We study the maximal speed of all particles during a given time period,which turns out to be a function of the packing dimension of the time period.We calculate the Hausdorff dimension of the set of a-fast patlls in the support and the range of the historical super-lévy process. 相似文献
993.
设X(t)(t∈R^N)是指数为α的d维分式Brown运动。本文研究X(t)的极函数问题,得出了满足P{t∈R^N\{0},X(t)=f(t)=0}的连续函数f组成的类的特征,解决了Legall提出的一个问题;并且得到了(N,N,2α)过程的不动点的Hausdorff维数。 相似文献
994.
995.
Viorel P. Paun 《Central European Journal of Physics》2009,7(2):264-269
The SEM microfractographies of Zircaloy-4 are studied by the time-series method. We first develop a computer application which
associates a time series to each SEM micrograph. Furthermore, we will apply the phase space embedding technique to reconstruct
the attractor and to compute the autocorrelation dimension. Using the fractal analysis technique, the SEM microfractographies
of the fracture surface of the Zircaloy-4 samples have been analyzed.
相似文献
996.
通过相空间重构技术,对Brent和WTI原油价格增长率的时间序列分别进行相空间重构,将若干固定时间延迟点上的数据作为新维处理,形成相点,应用Wolf方法得出了最大的Lyapunov指数,从而给出了系统混沌存在的证据;利用关联函数求出了关联维度和Kolmogorov熵,从而给出了对系统的混沌程度的估计和对Brent和WTI原油价格进行有效性预测的时间尺度. 相似文献
997.
A quasi-geostrophic intermediate complexity model of the mid-latitude atmospheric circulation is considered, featuring simplified baroclinic conversion and barotropic convergence processes. The model undergoes baroclinic forcing towards a given latitudinal temperature profile controlled by the forced equator-to-pole temperature difference TE. As TE increases, a transition takes place from a stationary regime-Hadley equilibrium-to a periodic regime, and eventually to a chaotic regime where evolution takes place on a strange attractor. The attractor dimension, metric entropy, and bounding box volume in phase space have a smooth dependence on TE, which results in power-law scaling properties. Power-law scalings with respect to TE are detected also for the statistical properties of global physical observables — the total energy of the system and the averaged zonal wind. The scaling laws, which constitute the main novel result of the present work, can be thought to result from the presence of a statistical process of baroclinic adjustment, which tends to decrease the equator-to-pole temperature difference and determines the properties of the attractor of the system. The self-similarity could be of great help in setting up a theory for the overall statistical properties of the general circulation of the atmosphere and in guiding-on a heuristic basis-both data analysis and realistic simulations, going beyond the unsatisfactory mean field theories and brute force approaches. A leading example for this would be the possibility of estimating the sensitivity of the output of the system with respect to changes in the parameters. 相似文献
998.
Duan-Ming Zhang Zhi-Yuan Chen Yan-Ping Yin Rui Li Xiang-Ying Su Wen-Jing Yang Ming-Tao Huang Hong-Ying Zhu Ling Zhang 《Physica A》2007
A one-dimensional dynamic model of polydisperse granular mixture with a power-law size distribution is presented, in which the particles are subject to inelastic mutual collisions and driven by Gaussian white noise. The particle size distribution of the mixture has the fractal characteristic, and a fractal dimension D as a measurement of the inhomogeneity of the particle size distribution is introduced. We define the global granular temperature and the kinetic pressure of the mixture, and obtain their expressions. By molecular dynamics simulations, we have mainly investigated how the inhomogeneity of the particle size distribution and the inelasticity of collisions influence the steady-state dynamic properties of the system, focusing on the global granular temperature, kinetic pressure, velocity distribution and distribution of interparticle spacing. Some novel results are found that, with the increase of the fractal dimension D, the global granular temperature and the kinetic pressure decrease, the velocity distribution deviates more obviously from the Gaussian one and the particles cluster more pronouncedly at the same value of the restitution coefficient e (0<e<1). On the other hand, as the restitution coefficient e decreases, the dynamic behavior has the similar evolution as above at the fixed fractal dimension D. The dynamic behavior changing with e and D is, respectively, presented. 相似文献
999.
Jakob G. Heller Nikolai Neumaier Stefan Waldmann 《Letters in Mathematical Physics》2007,80(3):257-272
Locally noncommutative spacetimes provide a refined notion of noncommutative spacetimes where the noncommutativity is present
only for small distances. Here we discuss a non-perturbative approach based on Rieffel’s strict deformation quantization.
To this end, we extend the usual C
*-algebraic results to a pro-C
*-algebraic framework.
相似文献
1000.
A geometric model for the quantum nature of interaction fields is proposed. We utilize a trivial fibre bundle whose typical
fibre has a multiconnectivity characterized by a discrete group Γ. By seeing Γ as a gauge group with global action on each
fibre, we show that the corresponding field strength is non-zero only on the future part of the light cone whose vertex is
at the interaction point. When the interaction is submitted to the symmetries of a Lie group G, we consider the gauge group G x Γ. The field strength of the gauge having this group includes a term expressing the quantization of the interaction field
described by G. This geometric interpretation of quantization makes use of topological arguments similar to those applied to explain the
Aharonov-Bohm effect. Two examples show how this interpretation applies to the cases of electromagnetic and gravitational
fields.
相似文献