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81.
Generation and Quantum Interference of Entangled Electron-Hole Pairs in a Hanbury Brown and Twiss Interferometer 下载免费PDF全文
The Hanbury Brown-Twiss interferometer is proposed to serve as a detector of the crossed Andreev reflection and to generate entangled electron-hole pairs. It is shown that the non-local electron and hole induced by the crossed Andreev reflection are entangled. Quantum interference of the entangled electron-hole pairs gives rise to a new measurable effect of the phase difference between two superconductors in the cross correlation. The present theoretical predictions can be experimentally realized within the present-day microelectronic technology. 相似文献
82.
Electrical Response of Flexible Vanadyl-Phthalocyanine Thin-Film Transistors under Bending Conditions 下载免费PDF全文
Flexible vanadyl-phthalocyanine (VOPc) thin-film transistors are fabricated by the weak epitaxy growth (WEG) method. The devices show a mobility of 0.5 cm2/Vs, an on/off ratio of 105 and a low leakage current of 10-9 A. The performances exhibit strong dependence on bending conditions and reversible change can be found when the bending strain is less than 1.5%. This results from the change of the trap density calculated by subthreshold slopes. The results indicate that VOPc films fabricated by the WEG method have good durability to flexing and possess great potential in flexible electronics. 相似文献
83.
84.
根据爱因斯坦方程和Marcus电荷传输模型, 使用密度泛函理论B3lyp/6-31g**理论水平计算6 个吐昔烯衍生物分子的结构和电荷传输性质. 结果显示: 6个吐昔烯的衍生物分子的空穴迁移速率为0.018–0.062 cm2·V-1·s-1, 电子迁移率为0.055–0.070 cm2·V-1·s-1, 其中3, 8, 13-辛烷氧基吐昔烯衍生物分子适合作为双极性传输材料. 三条烷氧基链的吐昔烯衍生物分子上引入三个甲氧基或羟基, 均使空穴和电子传输率降低. 引入给电子基团或共轭性基团可减小吐昔烯衍生物分子的能隙, 达到有机半导体的能隙要求.
关键词:
吐昔烯衍生物
空穴传输
电子传输
有机半导体 相似文献
85.
以PEDOT∶PSS作为空穴注入层,聚合物PVK作为空穴传输层,制备了结构为ITO/PEDOT∶PSS/PVK/8-羟基喹啉钕(Ndq3)/Al的近红外OLED,研究了PVK与PEDOT∶PSS功能层对器件I-V特性和EL光谱的影响。结果显示,在EL光谱中的905,1 064,1 340 nm处均观察到了荧光发射,分别对应于Nd3+的4F3/2→4I9/2、4F3/2→4I11/2和4F3/2→4I13/2能级跃迁。与参考器件对比分析认为,PEDOT∶PSS高的导电性降低了器件的串联电阻,增大了器件的工作电流;PVK与PEDOT∶PSS共同降低了空穴的注入势垒,实现了Ndq3发光层区域的载流子的注入平衡并改善了器件的发射强度。此外,PVK有效降低了ITO电极表面粗糙度,也是器件性能提高的原因之一。 相似文献
86.
87.
本文利用60 MeV质子束流,开展了NAND (not and) flash存储器的质子辐照实验,获取了浮栅单元的单粒子翻转截面,分析了浮栅单元错误的退火规律,研究了质子辐照对浮栅单元的数据保存能力的影响.实验结果表明,浮栅单元单粒子翻转截面随质子能量的升高而增大,随质子注量的升高而减小.浮栅单元错误随着退火时间的推移持续增多,该效应在低能量质子入射时更为明显.经质子辐照后,浮栅单元的数据保存能力有明显的退化.分析认为高能质子通过与靶原子的核反应,间接电离导致浮栅单元发生单粒子翻转,翻转截面与质子注量的相关性是因为浮栅单元单粒子敏感性的差异.质子引起的非电离损伤会在隧穿氧化层形成部分永久性的缺陷损伤,产生可以泄漏浮栅电子的多辅助陷阱导电通道,导致浮栅单元错误增多及数据保存能力退化. 相似文献
88.
The interfacial characteristics of Al/Al2O3/ZnO/n-GaAs metal-oxide-semiconductor (MOS) capacitor are investigated. The results measured by X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) show that the presence of ZnO can effectively suppress the formations of oxides at the interface between the GaAs and gate dielectric and gain smooth interface. The ZnO-passivated GaAs MOS capacitor exhibits a very small hysteresis and frequency dispersion. Using the Terman method, the interface trap density is extracted from C-V curves. It is found that the ZnO layer can effectively improve the interface quality. 相似文献
89.
The effects of strain and surface roughness scattering on the quasi-ballistic characteristics of a Ge nanowire p-channel field-effect transistor 下载免费PDF全文
The effects of strain and surface roughness scattering on the quasi-ballistic hole transport in a strained gate-all-around germanium nanowire p-channel field-effect transistor (pFET) are investigated in this work. The valence subbands are shifted up and warped more parabolically by the influence of HfO2 due to the lattice mismatch. However, the boundary force only shifts the subbands downwards and has little effect on the reshaping of bands. Strain induced by HfO2 increases both the hole mobility and ON-current (/ON), but has little effect on the hole mobility. The/ON is degraded by the surface roughness scattering in both strained and unstrained devices. 相似文献
90.
Dielectric relaxation and charge transport induced by electron hopping in ZnO single crystal are measured by using a novocontrol broadband dielectric spectrometer. Typical Debye-like dielectric relaxation originating from electronic hopping between electronic traps and conductive band in surface Schottky barrier region is observed for ZnO single crystal-Au electrode system. However, after insulation of ZnO single crystal by heat treatment in rich oxygen atmosphere, dielectric relaxation and alternating current conductance are observed simultaneously in the dielectric spectra, implying that dielectric relaxation and charge transport can be induced simultaneously by electronic hopping at high temperature in an ordered system. The intrinsic correlation between local dielectric relaxation and long range charge transport offers us a new method to explore complicated dielectrics. 相似文献