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991.
The classical first law of thermodynamics for a Kerr–Newman black hole (KNBH)is generalized to a law in quantum form on the event horizon. Then four quantumconservation laws on the KNBH equilibrium radiation process are derived. TheBekenstein–Hawking relation S = A/4 is exactly established. It can be inferredthat the classical entropy of black hole arises from the quantum entropy of fieldquanta or quasiparticles inside the hole. 相似文献
992.
WavelengthsofFiveNi-LikeLaserLines¥G.X.Chen;Q.Y.Fang;W.Cai(InstituteofAppliedPhysicsandComputationalMathematicsP.O.BOX8009Bei... 相似文献
993.
Dislocation velocities in silicon in the experimental range of temperature and stress are studied a priori by combining a mechanistic treatment of elementary kink processes with activation energies obtained by atomistic calculations. Pronounced effects of intrinsic coupling of the dissociated partial dislocations are captured in kinetic Monte Carlo simulations, which are consistent with observed velocity variations with applied stress. As a result, the nature of "weak obstacles" to kink propagation, a long-standing postulate in previous data interpretation, is clarified. A striking new effect is predicted and offered for experimental verification when dislocation velocity shows nonmonotonic oscillatory behavior with increasing stress. 相似文献
994.
995.
Yi-Fu Cai 《中国科学:物理学 力学 天文学(英文版)》2014,57(8):1414-1430
From recent observational data two significant directions have been made in the field of theoretical cosmology recently.First,we are now able to make use of present observations,such as the Planck and BICEP2 data,to examine theoretical predictions from the standard inflationaryΛCDM which were made decades of years ago.Second,we can search for new cosmological signatures as a way to explore physics beyond the standard cosmic paradigm.In particular,a subset of early universe models admit a nonsingular bouncing solution that attempts to address the issue of the big bang singularity.These models have achieved a series of considerable developments in recent years,in particular in their perturbative frameworks,which made brand-new predictions of cosmological signatures that could be visible in current and forthcoming observations.Herein we present two representative paradigms of early universe physics.The first is the reputed new matter(or matter-ekpyrotic)bounce scenario in which the universe starts with a matter-dominated contraction phase and transitions into an ekpyrotic phase.In the setting of this paradigm,we have proposed some possible mechanisms of generating a red tilt for primordial curvature perturbations and confront the general predictions with recent cosmological observations.The second is the matter-bounce inflation scenario which can be viewed as an extension of inflationary cosmology with a matter contraction before inflation.We present a class of possible model constructions and review the implications on the current CMB experiments.Lastly a review of significant achievements of these paradigms beyond the inflationaryΛCDM model is made,which is expected to shed new light on the future direction of observational cosmology. 相似文献
996.
Band-stop optical nanofilters with split-ring resonators based on metal–insulator–metal structure 下载免费PDF全文
Novel band-stop filters with circular split-ring resonators based on the metal–insulator–metal(MIM) structure are presented, with their transmission properties of SPPs propagating through the filter simulated by the finite-difference timedomain(FDTD) method. The variation of the gap of the split ring can affect the transmission characteristics, i.e., the transmission spectrum of SPPs exhibiting a shift, which is useful for modulating the filter. Linear and nonlinear media are used in the resonator respectively. By varying the refractive index of the linear medium, the transmission properties can be changed obviously, and the effect caused by changing the incident intensity with a nonlinear medium is similar.Several resonant modes that are applicable can be enhanced by changing the position of the gap of the split ring. Thus, the transmission properties can be modulated by adjusting the size of the gap, varying the refractive index, and changing the incident intensity of the input light. These methods may play significant roles in applications of optical integrated circuits and nanostructural devices. 相似文献
997.
998.
用345 keV的Kr15+和340 keV的Kr17+离子以45fi角入射n型GaAs单晶(100)面,测量了表面形貌的变化和发射的375—500 nm Ga I和Kr II的特征光谱线.Krq+(q=15,17)离子轰击后表面形貌的变化主要取决于入射离子的电荷态q.离子沉积到靶表面的能量引起Ga原子激发,其辐射光谱为Ga I 403.2 nm和Ga I 417.0 nm.入射离子中性化过程中俘获GaAs导带电子形成高激发态原子,通过级联退激填充3p,4d等空穴,P壳层电子跃迁发射谱线为Kr II 410.0 nm,Kr II 430.4 nm,Kr II 434.0 nm和Kr II 486.0 nm,Kr II486.0 nm为较强谱线.实验结果表明,入射离子与GaAs单晶相互作用发射的可见光产额与入射离子的电荷态密切相关,较高电荷态Kr17+离子入射产生的光辐射产额大约为Kr15+离子的两倍. 相似文献
999.
研究了在内噪声、外噪声(固有频率涨落噪声)及周期激励信号共同作用下具有指数型记忆阻尼的广义Langevin方程的共振行为.首先将其转化为等价的三维马尔可夫线性系统,再利用Shapiro-Loginov公式和Laplace变换导出系统响应一阶矩和稳态响应振幅的解析表达式.研究发现,当系统参数满足Routh-Hurwitz稳定条件时,稳态响应振幅随周期激励信号频率、记忆阻尼及外噪声参数的变化存在"真正"随机共振、传统随机共振和广义随机共振,且随机共振随着系统记忆时间的增加而减弱.数值模拟计算结果表明系统响应功率谱与理论结果相符. 相似文献
1000.
Elastic scattering angular distributions and total reaction cross-sections of ~(7,10,11,12)Be projectiles are predicted by the systematic ~9 Be global phenomenological optical model potential for target mass numbers ranging from24 to 209. These predictions provide a detailed analysis by their comparison with the available experimental data.Furthermore, these elastic scattering observables are also predicted for some targets out of the mass number range.The results are in reasonable agreement with the existing experimental data, and they are presented in this study. 相似文献