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81.
The absorption spectrum of the 16O3 isotopologue of ozone has been recorded in the 7000-7920 cm−1 region by high sensitivity CW-Cavity Ring Down Spectroscopy. This report is devoted to the analyses of the 7065-7300 cm−1 region dominated by the ν1 + 2ν2 + 5ν3 and ν1 + 5ν2 + 3ν3 A-type bands at 7130.8 and 7286.8 cm−1 respectively. 289 transitions were assigned to the ν1 + 2ν2 + 5ν3 band. The corresponding line positions were modeled with an effective Hamiltonian involving Coriolis resonance interactions between the (1 2 5) upper state and the (4 4 0), (0 2 6) and (6 1 0) dark states, and an anharmonic resonance interaction with the (2 0 5) state. The very strong interaction (up to 50% mixing of the wavefunctions) between the (1 2 5) and (6 1 0) states leads to the observation of two extra lines of the 6ν1 + ν2 band due to a resonance intensity transfer. 213 transitions of the ν1 + 5ν2 + 3ν3 band were assigned and modeled taking into account a Coriolis resonance interaction with the (3 6 0) state.We take the opportunity of the present work to report the analysis of the very weak 4ν2 + 4ν3 B-type band at 6506.1 cm−1 which was assigned from previously recorded CRDS spectra. 286 transitions were modeled using the effective Hamiltonian approach.The dipole transition moment parameters of the three analyzed bands were determined by a least-squares fit to the measured line intensities. For the three studied band systems, the effective Hamiltonian and transition moment operator parameters were used to generate line lists provided as Supplementary Materials. 相似文献
82.
Robert Buras Bernhard Mayer 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(3):434-7735
We present five new variance reduction techniques applicable to Monte Carlo simulations of radiative transfer in the atmosphere: detector directional importance sampling, n-tuple local estimate, prediction-based splitting and Russian roulette, and circum-solar virtual importance sampling. With this set of methods it is possible to simulate remote sensing instruments accurately and quickly. In contrast to all other known techniques used to accelerate Monte Carlo simulations in cloudy atmospheres - except for two methods limited to narrow angle lidars - the presented methods do not make any approximations, and hence do not bias the result. Nevertheless, these methods converge as quickly as any of the biasing acceleration techniques, and the probability distribution of the simulation results is almost perfectly normal. The presented variance reduction techniques have been implemented into the Monte Carlo code MYSTIC (“Monte Carlo code for the physically correct tracing of photons in cloudy atmospheres”) in order to validate the techniques. 相似文献
83.
董明德 《应用数学和力学(英文版)》1985,6(4):307-320
In connection with non-Fuchsian equations Poincaré has made an important conclusion: It is impossible to obtain explicit expressions of irregular integrals
.To elucidate the essence of Poincaré's problem, we establish correspondence theorem. Irregular integrals are analytic functions of new kind, possessing tree structure; part of which can be represented by conventional recursive series, while its remaining part is expressed by the so-called tree series, not subjecting to any recursive relation at all.In contrast to the numerical solution calculated by infinite determinant of classical theory (Hill-Poincaré-von Koch), our method yields naturally exact analytic solution in explicit form. The method proposed may be used to construct a unifying theory for general equations with variable coefficients, having various kinds of singularities as singular lines.The significance of Poincaré conjecture is discussed, the tree series obtained belong to higher automorphic functions. 相似文献
84.
The convection in atmosphere discussed in ref. [1] is rigorously treated by considering the variation of environmental temperature
with the height. This represents an example of applications of the elementary catastrophe theory in Hamiltonian systems. 相似文献
85.
An existence theorem of two positive solutions of the singular BVP1/(p(t))(p(t)y′(t))′+λα(t)f(y(t))=0,t∈(0,1),αy(0)-βp(t)y′(t)=0=γy(1)+δp(t)y′(t)was established by using topological degree theory. 相似文献
86.
In order to evaluate its relevance, we reconsider critically the recent proposal by Leggett and Garg to test macrorealism
against quantum mechanics by resorting to experiments involving noninvasive measurement processes on a SQUID. Our conclusion
is that, in spite of the fact that the proposed experiment would neither constitute a test of macrorealism nor a test of macrocontextuality,
a simplified form of it represents a (presumably) feasible experiment permitting a direct test of macroscopic quantum coherence.
We also analyze the proposal from the point of view of the recent attempts to build up model theories allowing to take, within
a purely quantum framework, a macrorealistic position about natural phenomena, i.e., the socalled dynamical reduction models
and we stress that the proposed experiment has no relevance for the dynamical reduction program, as developed so far. However
consideration of the SQUID system allows one to test other possible dynamical mechanisms leading to the objectification of
macroproperties which could, in principle, be operative. We also briefly sketch experimental procedures to be followed to
get all relevant information concerning macrocoherence. 相似文献
87.
本文研究电子与体纵光学声子耦合弱、与表面光学声子耦合强的半无限晶体中的表面极化子的性质.采用改进了的线性组合算符法和微扰法导出了半无限晶体中的慢速运动极化子的有效哈密顿量.在计及电子在反冲效应中发射和吸收的不同波矢的声子之间的相互作用时,讨论了对有效哈密顿量,诱生势和有效质量的影响.对AgBr晶体进行了数值计算,结果表明反冲效应中发射和吸收的不同波矢的声子之间的相互作用对有效质量和诱生势的影响随耦合常数αt的增加而增加,对有效质量的影响随坐标z的增加而减小的更多,对诱生势的影响随z的增加而增加的更多. 相似文献
88.
Stefan Wewers 《Journal of the American Mathematical Society》2003,16(4):991-1032
We study Galois covers of the projective line branched at three points with bad reduction to characteristic , under the condition that strictly divides the order of the Galois group. As an application of our results, we prove that the field of moduli of such a cover is at most tamely ramified at .
89.
We consider a fifth-order partial differential equation (PDE) that is a generalization of the integrable Camassa–Holm equation. This fifth-order PDE has exact solutions in terms of an arbitrary number of superposed pulsons with a geodesic Hamiltonian dynamics that is known to be integrable in the two-body case N==2. Numerical simulations show that the pulsons are stable, dominate the initial value problem, and scatter elastically. These characteristics are reminiscent of solitons in integrable systems. But after demonstrating the nonexistence of a suitable Lagrangian or bi-Hamiltonian structure and obtaining negative results from Painlevé analysis and the Wahlquist–Estabrook method, we assert that this fifth-order PDE is not integrable. 相似文献
90.
This paper deals with the solvability of boundary value problems for singular integral equations of the form (i)-(ii).By an algebraic method we reduce the problem (i)-(ii) to a system of linear algebraic equations which gives all solutions in a closed form.AMS Subject Classification: 47G05, 45GO5, 45E05 相似文献