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941.
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
942.
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
943.
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
944.
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
945.
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
946.
947.
We consider the Shigesada-Kawasaki-Teramoto cross-diffusion model for two competing species. If both species have the same random diffusion coefficients and the space dimension is less than or equal to three, we establish the global existence and uniform boundedness of smooth solutions to the model in convex domains. This extends some previous works of Kim [12] and Shim [21] in one dimensional space. 相似文献
948.
Chang-Gong Li Yong-Fang Li Jing-Yan Shang Tian-Jun Lou 《Transition Metal Chemistry》2014,39(4):373-378
Carbonyl substitution reactions of [μ-(SCH2)2CHC6H5]Fe2(CO)6 with bidentate phosphine ligands, cis-1,2-bis(diphenylphosphine)ethylene (cis-dppv) and N,N-bis(diphenylphosphine)propylamine [(Ph2P)2N-Pr-n], yielded an asymmetrically substituted chelated complex [(μ-SCH2)2CHC6H5]Fe2(CO)4(k 2-dppv) and a symmetrically substituted bridging complex [(μ-SCH2)2CHC6H5]Fe2(CO)4[μ-(PPh2)2N-Pr-n] under different reaction conditions. Both complexes were fully characterized by spectroscopic methods and by X-ray crystallography. Their electrochemical behaviors were observed by cyclic voltammetry, and the catalytic electrochemical reduction of protons from acetic or trifluoroacetic acid to give dihydrogen mediated by complex [(μ-SCH2)2CHC6H5]Fe2(CO)4(k 2-dppv) was investigated. 相似文献
949.
Zhiyu Xie Lei Liu Wenfang Chen Hongbo Zheng Qingqing Xu Huiqing Yuan Hongxiang Lou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(15):3985-3989
Described is a practical and universal C H functionalization of readily removable N‐benzyl and N‐allyl carbamates, with a wide range of nucleophiles at ambient temperature promoted by Ph3CClO4. The metal‐free reaction has an excellent functional‐group tolerance, and displays a broad scope with respect to both N‐carbamates and nucleophile partners (a variety of organoboranes and C H compounds). The synthetic utility in target‐ as well as diversity‐oriented syntheses is demonstrated. 相似文献
950.