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161.
162.
Y. Zhang T. M. Benson P. Sewell A. Vukovic D. Zhang W. J. Pan A Loni D. Furniss A. B. Seddon 《Optical and Quantum Electronics》2006,38(1-3):97-110
This paper presents our recent simulation results and novel designs of single mode large cross-section glass-based waveguides for photonic integrated circuits (PICs). Simulations were performed using an in-house Finite Difference (FD) based mode solver and the FD Beam propagation Method (FD-BPM). Our simulation results show that this innovative technology could provide a simplified means to couple optical energy efficiently between optical components in a single chip. This would provide the base for the future large-scale integration of optical components in PICs. The novel idea of using single mode large cross-section glass-based waveguides as an optical integration platform is an evolutionary innovative solution for the monolithic integration of optical components, in which the glass-based structures act both as waveguides and as an optical bench for integration. This allows easy and efficient optical coupling between optical components and optical fibres, removing costly and tedious alignment problems and considerably reducing optical coupling losses in PICs. We expect that the glass-based waveguide PICs technology will enable the emergence of a new generation of compact, reliable, high speed, and multifunctional devices. 相似文献
163.
D. Chiladze J. Carbonell S. Dymov V. Glagolev M. Hartmann V. Hejny A. Kacharava I. Keshelashvili A. Khoukaz H.R. Koch V. Komarov P. Kulessa A. Kulikov G. Macharashvili Y. Maeda T. Mersmann S. Merzliakov S. Mikirtytchiants A. Mussgiller M. Nioradze H. Ohm F. Rathmann R. Schleichert H.J. Stein H. Ströher Yu. Uzikov S. Yaschenko C. Wilkin 《Physics letters. [Part B]》2006
164.
Highly ordered composite nanowires with multilayer Ni/Cu and NiFe/Cu have been fabricated by pulsed electrodeposition into
nanoporous alumina membrane. The diameter of wires can be easily varied by pore size of alumina, ranging from 30 to 100 nm.
The applied potential and the duration of each potential square pulse determine the thickness of the metal layers. The nanowires
have been characterized by transmission electron microscopy (TEM), magnetic force microscopy (MFM), and vibrating sample magnetometer
(VSM) measurements. The MFM images indicate that every ferromagnetic layer separated by Cu layer was present as single isolated
domain-like magnet. This technique has potential use in the measurement and application of magnetic nanodevices. 相似文献
165.
Recently commercial equipment using sedimentation field flow fractionation (SFFF) has become available for analysis of particulate materials in the sub-micron range. This paper describes the DuPont instrument and discusses its performance. A particular study is described on the comparison of the SFFF technique with that of quasi-elastic light scattering (QELS). The paper concludes that the instrument is capable of measuring particle size distributions with high resolution and precision, provided that no particles above the upper size limit — about 1 μm — are present. 相似文献
166.
167.
S. S. Dragomir Y. J. Cho S. S. Kim J. Roumeliotis 《Journal of Applied Mathematics and Computing》2006,20(1-2):279-292
A reverse of Bessel’s inequality in 2-inner product spaces and companions of Grüss inequality with applications for determinantal integral inequalities are given. 相似文献
168.
S. S. Banerjee S. Goldberg Y. Myasoedov M. Rappaport E. Zeldov A. Soibel F. de la Cruz J. van der Beek M. Konczykowski T. Tamegai V. Vinokur 《Pramana》2006,66(1):43-54
Disorder and porosity are parameters that strongly influence the physical behavior of materials, including their mechanical,
electrical, magnetic and optical properties. Vortices in superconductors can provide important insight into the effects of
disorder because their size is comparable to characteristic sizes of nanofabricated structures. Here we present experimental
evidence for a novel form of vortex matter that consists of inter-connected nanodroplets of vortex liquid caged in the pores
of a solid vortex structure, like a liquid permeated into a nanoporous solid skeleton. Our nanoporous skeleton is formed by
vortices pinned by correlated disorder created by high-energy heavy ion irradiation. By sweeping the applied magnetic field,
the number of vortices in the nanodroplets is varied continuously from a few to several hundred. Upon cooling, the caged nanodroplets
freeze into ordered nanocrystals through either a first-order or a continuous transition, whereas at high temperatures a uniform
liquid phase is formed upon delocalization-induced melting of the solid skeleton. This new vortex nanoliquid displays unique
properties and symmetries that are distinct from both solid and liquid phases. 相似文献
169.
The stagnation slip flow on an axially moving cylinder is studied.The NavierStokes and energy equations reduce to nonlinearordinary differential equations under a similarity transform.For large slip, the flow field decays exponentially into potentialflow. The heat transfer can be expressed as an incomplete gammafunction. In general, the heat transfer increases with slip,Prandtl number and Reynolds number. 相似文献
170.
Y.-Q. Peng J.-H. Yang F.-P. Lu 《Applied Physics A: Materials Science & Processing》2006,83(2):305-311
Under the assumption of Gaussian energy distributions of the lowest unoccupied molecular orbital (LUMO) and the highest occupied
molecular orbital (HOMO), analytical expressions of generalized Einstein relation for electron and hole transport in doped
organic semiconductor thin films are developed. Numerical calculations show that, although traditional Einstein relation still
holds for low carrier concentrations, that is, the diffusion-coefficient-to-mobility ratio in units of kBT/q, with kB the Boltzmann’s constant, T the temperature and q the elementary charge, equals 1. But when the electron (hole) concentration
is high, the diffusion-coefficient-to-mobility ratio for electrons (holes) changes strongly with the electron (hole) concentration,
the doping level, the mean energy of LUMOs (HOMOs) of the dopant ELd (EHd) and the host EL (EH), as well as their variances. Dopants with ELd<EL (EHd>EH) affect the diffusion-coefficient-to-mobility ratio mainly in the range of low and middle carrier concentrations, while those
with ELd>EL (EHd<EH) have significant effect only in the range of high carrier concentrations. It was found that there can be a maximum in the
dependence of the diffusion-coefficient-to-mobility ratio on the quasi-Fermi energy or carrier concentration exist, for appropriate
values of the doping level, the mean energy and variance of LUMO or HOMO states of the dopant.
PACS 71.20.Rv; 72.90.+y; 73.50.-h 相似文献