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991.
Giovanni DiLena Basilio Messano Delfina Roux 《Proceedings of the American Mathematical Society》1997,125(12):3575-3580
We introduce a new class of normed spaces (not necessarily finite dimensional), which contains the finite dimensional normed spaces with polyhedral norm. We study the properties of rigid sets of the spaces of this class and we apply the results to limit sets of the sequences of iterates of nonexpansive maps.
992.
We study a Fermi gas with general translation-invariant many-body interactions on a (v3)-dimensional lattice. A complete analysis is given of the perturbative terms up to second order and the program put forward by N. M. Hugenholtz for the derivative of the Boltzmann equation is verified to second order. 相似文献
993.
Remco van der Hofstad 《Journal of statistical physics》1998,90(5-6):1295-1310
The Edwards model in one dimension is a transformed path measure for one-dimensional Brownian motion discouraging self-intersections. We study the constants appearing in the central limit theorem (CLT) for the endpoint of the path (which represent the mean and the variance) and the exponential rate of the normalizing constant. The same constants appear in the weak-interaction limit of the one-dimensional Domb–Joyce model. The Domb–Joyce model is the discrete analogue of the Edwards model based on simple random walk, where each self-intersection of the random walk path recieves a penalty e
–2. We prove that the variance is strictly smaller than 1, which shows that the weak interaction limits of the variances in both CLTs are singular. The proofs are based on bounds for the eigenvalues of a certain one-parameter family of Sturm–Liouville differential operators, obtained by using monotonicity of the zeros of the eigen-functions in combination with computer plots. 相似文献
994.
Henri Carayol 《Compositio Mathematica》1998,111(1):51-88
Let G be an inner anisotropic form of an unitary group of 3 variables over Q, such that GRU(2,1), and be an automorphic representation of G(A) whose archimedean component is a degenerate limit of discrete series; such a never occurs in the cohomology (coherent or étale) of a Shimura variety. We show that however it does appear in the coherent cohomology of some line bundle over an associated Griffiths-Schmid variety. Moreover we study cup products between such cohomology classes and some other automorphic cohomology classes and we prove some non-vanishing results. 相似文献
995.
A discrete universality theorem is obtained in the Voronin sense for the L-functions of elliptic curves. We use the difference of an arithmetical progression h > 0 such that \(\exp \left\{ {\frac{{2\pi k}}{h}} \right\}\) is rational for some k ≠ 0. A limit theorem in the space of analytic functions plays a crucial role in the proof. 相似文献
996.
Alexander L. Stolyar 《Queueing Systems》2008,59(1):1-35
We consider a discrete-time model where multiple queues, each with its own exogenous arrival process, are served by a server
whose capacity varies randomly and asynchronously with respect to different queues. This model is primarily motivated by the
problem of efficient scheduling of transmissions of multiple data flows sharing a wireless channel.
We address the following problem of controlling large deviations of the queues: find a scheduling rule, which is optimal in
the sense of maximizing
where Q
i
is the length of the i-th queue in a stationary regime, and a
i
>0 are parameters. Thus, we seek to maximize the minimum of the exponential decay rates of the tails of distributions of weighted
queue lengths a
i
Q
i
. We give a characterization of the upper bound on (0.1) under any scheduling rule, and of the lower bound on (0.1) under
the exponential (EXP) rule. We prove that the two bounds match, thus proving optimality of the EXP rule. The EXP rule is very parsimonious
in that it does not require any “pre-computation” of its parameters, and uses only current state of the queues and of the
server.
The EXP rule is not invariant with respect to scaling of the queues, which complicates its analysis in the large deviations
regime. To overcome this, we introduce and prove a refined sample path large deviations principle, or refined Mogulskii theorem, which is of independent interest.
相似文献
(0.1) |
997.
It has been shown that the MARLAP (Multi-Agency Radiological Laboratory Analytical Protocols) for estimating the Currie detection limit, which is based on ‘critical values of the non-centrality parameter of the non-central t distribution’, is intrinsically biased, even if no calibration curve or regression is used. This completed the refutation of the method, begun in Part 2. With the field cleared of obstructions, the true theory underlying Currie's limits of decision, detection and quantification, as they apply in a simple linear chemical measurement system (CMS) having heteroscedastic, Gaussian measurement noise and using weighted least squares (WLS) processing, was then derived. Extensive Monte Carlo simulations were performed, on 900 million independent calibration curves, for linear, “hockey stick” and quadratic noise precision models (NPMs). With errorless NPM parameters, all the simulation results were found to be in excellent agreement with the derived theoretical expressions. Even with as much as 30% noise on all of the relevant NPM parameters, the worst absolute errors in rates of false positives and false negatives, was only 0.3%. 相似文献
998.
Let be a C*-dynamical system where be a semigroup of injective endomorphism and ψ be an (λt) invariant state on the C* subalgebra and is either non-negative integers or real numbers. The central aim of this exposition is to find a useful criteria for the inductive limit state canonically associated with ψ to be pure. We achieve this by exploring the minimal weak forward and backward Markov processes associated with the Markov semigroup on the corner von-Neumann algebra of the support projection of the state ψ to prove that Kolmogorov's property [A. Mohari, Markov shift in non-commutative probability, J. Funct. Anal. 199 (2003) 189–209] of the Markov semigroup is a sufficient condition for the inductive state to be pure. As an application of this criteria we find a sufficient condition for a translation invariant factor state on a one-dimensional quantum spin chain to be pure. This criteria in a sense complements criteria obtained in [O. Bratteli, P.E.T. Jorgensen, A. Kishimoto, R.F. Werner, Pure states on , J. Operator Theory 43 (1) (2000) 97–143; A. Mohari, Markov shift in non-commutative probability, J. Funct. Anal. 199 (2003) 189–209] as we could go beyond lattice symmetric states. 相似文献
999.
Helge Glöckner 《Journal of Functional Analysis》2007,245(1):19-61
Let G be a Lie group which is the union of an ascending sequence G1⊆G2⊆? of Lie groups (all of which may be infinite-dimensional). We study the question when in the category of Lie groups, topological groups, smooth manifolds, respectively, topological spaces. Full answers are obtained for G the group Diffc(M) of compactly supported C∞-diffeomorphisms of a σ-compact smooth manifold M; and for test function groups of compactly supported smooth maps with values in a finite-dimensional Lie group H. We also discuss the cases where G is a direct limit of unit groups of Banach algebras, a Lie group of germs of Lie group-valued analytic maps, or a weak direct product of Lie groups. 相似文献
1000.