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121.
Oscillation and nonoscillation criteria for the higher order self-adjoint differential equation (-1)n(talphay(n))(n)+q(t)y = 0 (*) are established. In these criteria, equation (*) is viewed as a perturbation of the conditionally oscillatory equation (-1)n(talphay(n))(n) - µ,t2n-y = 0, where
n, is the critical constant in conditional oscillation. Some open problems in the theory of conditionally oscillatory, even order, self-adjoint equations are also discussed. 相似文献
122.
We study time dependence of various measures of entanglement (covariance entanglement coefficient, purity entanglement coefficient, normalized distance coefficient, entropy coefficients) between resonantly coupled modes of the electromagnetic field in ideal cavities with oscillating boundaries. Two types of cavities are considered — a three-dimensional cavity possessing eigenfrequencies 3 = 31, whose wall oscillates at the frequency w = 21, and a one-dimensional (Fabry–Perot) cavity with an equidistant spectrum n = n1 where the distance between perfect mirrors oscillates at the frequencies 1 and 21. The behavior of entanglement measures in these cases turns out to be completely different, although all three coefficients demonstrate qualitatively similar time dependences in each case (except some specific situations where the covariance entanglement coefficient based on traces of covariance submatrices seems to be essentially more sensitive to entanglement than other measures, which are based on determinants of covariance submatrices). Different initial states of the field, namely, vacuum, squeezed vacuum, thermal, Fock, and even/odd coherent states, are considered. 相似文献
123.
We propose a simple scheme to generate two-mode entangled coherent state in two separated cavities and realize the entanglement
reciprocation between the superconducting charge qubits and continuous-variable system. By measuring the state of charge qubits,
we find that the entanglement of two charge qubits, which are initially prepared in the maximally entangled state, can be
transferred to the two-cavity field, and at this time the two-cavity field is in the entangled coherent state. We also find
that the entanglement can be retrieved back to the two charge qubits after measuring the state of the two-cavity field.
相似文献
124.
Field of View Increase for Optical Heterodyne Receivers 总被引:1,自引:0,他引:1
A. Waksberg 《International Journal of Infrared and Millimeter Waves》1999,20(6):1059-1071
The field of view of optical heterodyne systems are usually limited by a simple criterion- namely, that ARR 2, where AR is an effective aperture, R the corresponding field of view and the optical wavelength. This paper will demonstrate that with a simple change of systems geometry and the possible use of array detectors, this severe restriction can be alleviated considerably and, in some cases, eliminated. Both coherent sources and thermal radiation sources are considered. This might suggest that heterodyne systems that were eliminated in the past because of that criterion alone, could turn out to be, not only possible, but even advantageous compared to other techniques. 相似文献
125.
Zhen-han Tu 《Proceedings of the American Mathematical Society》1999,127(4):1039-1049
By applying the heuristic principle in several complex variables obtained by Aladro and Krantz, we shall prove some normality criteria for families of holomorphic mappings of several complex variables into , the complex N-dimensional projective space, related to Green's and Nochka's Picard type theorems. The equivalence of normality to being uniformly Montel at a point will be obtained. Some examples will be given to complement our theory in this paper.
126.
Włodzimierz Ogryczak 《Annals of Operations Research》1994,51(1):33-44
Real-life decision problems are usually so complex they cannot be modeled with a single objective function, thus creating a need for clear and efficient techniques of handling multiple criteria to support the decision process. The most commonly used technique is Goal Programming. It is clear and appealing, but in the case of multiobjective optimization problems strongly criticized due to its noncompliance with the efficiency (Pareto-optimality) principle. On the other hand, the reference point method, although using similar control parameters as Goal Programming, always generates efficient solutions. In this paper, we show how the reference point method can be modeled within the Goal Programming methodology. It allows us to simplify implementations of the reference point method as well as shows how Goal Programming with relaxation of some traditional assumptions can be extended to a multiobjective optimization technique meeting the efficiency principle. 相似文献
127.
128.
Reinhard Weber 《European Journal of Operational Research》1985,19(1):104-113
The subject of this paper is the formulation and discussion of a semi-infinite linear vector optimization problem which extends multiple objective linear programming problems to those with an infinite number of objective functions and constraints. Furthermore it generalizes in some way semi-infinite programming. Besides the statement of some immediately derived results which are related to known results in semi-infinite linear programming and vector optimization, the problem mentioned above is interpreted as a decision model, under risk or uncertainty containing continuous random variables. Thus we treat the case of an infinite number of occuring states of nature. These types of problems frequently occur within aspects of decision theory in management science. 相似文献
129.
Chang-yong?ChenEmail author Ke-lin?Gao 《International Journal of Theoretical Physics》2005,44(8):1177-1191
The physics realization of a ququadrit quantum computation with cooled trapped 138Ba+ ions in a Paul trap is investigated. The ground state level 62 S1/2(m = −1/2) and three metastable levels: 52 D3/2(m = −1/2), 52 D5/2(m = −1/2), and 52 D5/2(m = 1/2), of the fine-structure of the 138Ba+ ion, are used to store the quantum information of ququadrits. The use of coherent manipulation of populations in single ququadrit,
being a four-dimensional Hilbert space, produces a discrete Fourier transform and the manipulation of the first red band transitions
with the introduction of an ancillary quantum channel between two ququadrits generates a conditional phase gate. The combination
of the both above results in a universal two-ququadrit gate, called XOR(4) gate corresponding to the controlled-NOT gate operation in qubit systems. The implementation of quantum Fourier transform
for n ququadrits is performed by means of the conditional phase-shift gate. The feasibility of physical realization of ququadrit
quantum computation with cooled-trapped 138Ba+ ions is detailed analyzed and described, and the theoretical detection method of logical states is given. Higher entanglement
between ququadrits than qutrits or qubits and more security of ququadrit quantum cryptography than qutrit's or qutrit's will
lead to more extensive applications ququadrits in quantum information fields. In particular, it is pointed out that this scheme
should be the highest dimensional quantum computation in cooled-trapped ions, the entanglement between ququadrits should be
the highest dimensional entanglement in it, and the ququadrit quantum cryptography should be the most secure cryptography
protocol in it. 相似文献
130.
Karol?Horodecki Micha??HorodeckiEmail author Pawel?Horodecki Jonathan?Oppenheim 《Foundations of Physics》2005,35(12):2027-2040
There are aspects of privacy theory that are analogous to quantum theory. In particular one can define distillable key and
key cost in parallel to distillable entanglement and entanglement cost. We present here classical privacy theory as a particular
case of information theory with adversaries, where similar general laws hold as in entanglement theory. We place the result
of Renner and Wolf—that intrinsic information is lower bound for key cost—into this general formalism. Then we show that the
question of whether intrinsic information is equal to key cost is equivalent to the question of whether Alice and Bob can
create a distribution product with Eve using IM bits of secret key. We also propose a natural analogue of relative entropy of entanglement in privacy theory and show that
it is equal to the intrinsic information. We also provide a formula analogous to the entanglement of formation for classical
distributions.
It is our pleasure to dedicate this paper to Asher Peres on the occasion of his seventieth birthday. 相似文献