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971.
Senyue Lou 《中国科学A辑(英文版)》1997,40(12):1317-1324
The possible high dimensional integrable models are studied in three different aspects: (i) starting from a strong symmetry
operator of a known (1+1) -dimensional integrable model, we can construct a type of (n+1)-dimensional integrable models, high
dimensional breaking soliton equations; (ii) from every concrete realization of the generalized Virasoro algebra, we can get
many high dimensional integrable models in the meaning that the models possess generalized Virasoro symmetry algebra; (iii)
starting from the Schwartz equations which possess conformal invariance, we can also get various high dimensional integrable
models in the meaning that they possess Painlevé property.
Project supported by the National Natural Science Foundation of China and the Natural Science Foundation of Zhejiang Province. 相似文献
972.
娄本东 《数学物理学报(B辑英文版)》2000,20(1)
1IntroductionLetEbeaBanachspaceandI=[O,l].ConsiderthesystemofHammersteinintegralequationsinE:wherekiEC[IxI,R'](i=1,2)arenonnegative,fieC[IxExE,E](i=1,2)andyt,YEC[I,E].Inthispaper,weinvestigatetheexistenceofeigenvectorsofsystem(l)bymeansoffixedpointindextheory.WealsogivesomeapplicationstoasystelllofSturm-Liouvilleproblemsofordinarydtherentialequations.Iuwl1atfollows,PdenotesthenormalconeofEwithanormalconstantN(see[1,2l):95u5vimplieslluII5N11vIl,whereoisthezeroelementofE.ExEisaBana… 相似文献
973.
S. Dayal R. Królicki Y. Lou X. Qiu J.C. Berlin M.E. Kenney C. Burda 《Applied physics. B, Lasers and optics》2006,84(1-2):309-315
The first real-time observation of the early events during energy transfer from a photoexcited CdSe nanoparticle to an attached
phthalocyanine molecule are presented in terms of a femtosecond spectroscopic pump–probe study of the energy transfer in conjugates
of CdSe nanoparticles (NPs) and silicon phthalocyanines (Pcs) with 120 fs time resolution. Four different silicon phthalocyanines
have been conjugated to CdSe NPs. All of these have proven potential for photodynamic therapy (PDT). In such NP-Pc conjugates
efficient energy transfer (ET) from CdSe NPs to Pcs occurs upon selective photoexcitation of the NP moiety. Spectral analysis
as well as time-resolved fluorescence up-conversion measurements revealed the structure and dynamics of the investigated conjugates.
Femtosecond transient differential absorption (TDA) spectroscopy was used for the investigation of the non-radiative carrier
and ET dynamics. The formation of excitons, trapped carriers states, as well as stimulated emission was monitored in the TDA
spectra and the corresponding lifetimes of these states were recorded. The time component for energy transfer was found to
be between 15 and 35 ps. The ET efficiencies are found to be 20-70% for the four Pc conjugates, according to fluorescence
quenching experiments. Moreover, as a result of the conjugation between NP and the Pcs the photoluminescence efficiency of
the Pc moieties in the conjugates do not strictly follow the quantum yields of the bare phthalocyanines.
PACS 73.63.Bd 相似文献
974.
Equations and theorems governing the flow of an inviscid, incompressible, continuously-stratified fluid in a gradually varying channel with an arbitrary cross section are developed. The stratification and longitudinal velocity are assumed to be uniform in the transverse direction, an assumption that is supported under the assumption of gradual topographic variations. Extended forms of Long's model and the Taylor–Goldstein equation are developed. Interestingly, the presence of topographic variation does not alter the necessary condition for instability (Richardson number ) nor the bounds on unstable eigenvalues (the semi-circle theorem). The former can be proved using a new technique introduced herein. For the special case of homogeneous shear flow, generalized versions of the theorems of Rayleigh and Fjørtoft do depend on the form of the topography, though no general tendency toward stabilization or destabilization is apparent. Previous results on the bounds and enumeration of neutral modes are also extended. The results should be of use in the hydraulic interpretation of exchange flow in sea straits. 相似文献
975.
利用气相平衡扩散法研制出掺镁不同组分的LiNbO3晶体 ,并对其极化特性进行了研究 .研究表明晶体的开关电场和自发极化不仅与晶体组分 [Li] [Nb]比有关而且与掺镁量有关 ,[Li] [Nb]比为 0 973掺入 2mol%MgO的近化学比LiNbO3晶体的开关电场仅为 1 8kV mm ,是同成分晶体的 1 12 ,且其极化结构的质量要远好于同成分LiNbO3晶体和近化学比LiNbO3晶体 . 相似文献
976.
H.L. Bai E.Y. Jiang P. Wu Z.D. Lou Y. Wang C.D. Wang 《Applied Physics A: Materials Science & Processing》1999,69(6):641-647
The structural characterization of heat-treated CN films fabricated by dual-facing-target sputtering for soft X-ray multilayer
mirrors was performed by means of X-ray diffraction (XRD), Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS).
The XRD analyses indicate a graphization process in the CN films during thermal annealing. The Raman analyses imply that the
primary bonding in the CN films is sp2. In other words, the formation of the sp3 bonding in the CN films can be suppressed effectively by doping with N atoms, and thus the thickness expansion resulting
from the changes in the density of CN films during annealing can be decreased considerably. This result is also clarified
by the increased conductivity measured. The XPS results give the information of the existence of the strong covalent bonding
between N and C atoms, which can slow down the tendency of the structural relaxation during annealing. These results suggest
that CN films suitable for soft X-ray multilayers used at high-temperature environments can be obtained by reactive dual-facing-target
sputtering. With the low-angle X-ray diffraction measurements, we do observe the enhanced thermal stability of CoN/CN multilayers.
Received: 2 October 1998 / Accepted: 21 April 1999 / Published online: 23 September 1999 相似文献
977.
用Taylor级数展开的方法得到含速率平方阻力项的一维相对论谐振子的运动微分方程.从守恒量的性质及运动微分方程出发得到了系统的Lagrange函数和守恒量的表达式.
关键词:
相对论谐振子
Lagrange函数
守恒量 相似文献
978.
利用气相平衡扩散法研制出掺镁不同组分的LiNbO3晶体,并对其极化特性进行了研究.研究表明晶体的开关电场和自发极化不仅与晶体组分[Li]/[Nb]比有关而且与掺镁量有关,[Li]/[Nb]比为0.973掺入2mol% MgO的近化学比LiNbO3晶体的开关电场仅为1.8kV/mm,是同成分晶体的1/12,且其极化结构的质量要远好于同成分LiNbO3晶体和近化学比LiNbO3晶体.
关键词:
气相平衡扩散
3晶体')" href="#">掺镁LiNbO3晶体
周期极化 相似文献
979.
All optical bit clock recovery is one of the key technologies for all optical 3R recovery. In this paper, a simple method applying the combination of Fabry–Perot (F–P) filter and semiconductor optical amplifier (SOA) for clock recovery is proposed. The effect of the F–P filter finesse on the clock recovery and the reduction in the amplitude fluctuation of the clock pulse by the SOA are discussed theoretically. With this technology 10 Gbit/s clock recovery with equal amplitude and wavelength transparency was realized experimentally. 相似文献
980.
光通信中波分复用技术是解决通信网络瓶颈的有效手段,近年来得到很大发展。以平面波导波分复用器件为核心的密集波分复用技术已经得到成功商用。蚀刻衍射光栅是平面波导密集波分复用器件中很有发展潜力的一种。原有蚀刻衍射光栅采用罗兰圆设计,输入输出在圆弧曲线上由条形波导引出;而平场输入/输出的蚀刻衍射光栅在很多应用中可以省去制作输入输出波导,大大简化制作工艺,同时能够保持良好的线性色散和聚集效果。给出了平场输入和输出蚀刻衍射光栅的设计方法,并利用标量衍射理论对设计的结果进行模拟,验证了平场输出蚀刻衍射光栅具有很好的分波效果。 相似文献