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Reverse blocking enhancement of drain field plate in Schottky-drain AlGaN/GaN high-electron mobility transistors 下载免费PDF全文
In this paper, we present the combination of drain field plate(FP) and Schottky drain to improve the reverse blocking capability, and investigate the reverse blocking enhancement of drain FP in Schottky-drain AlGaN/GaN high-electron mobility transistors(HEMTs). Drain FP and gate FP were employed in a two-dimensional simulation to improve the reverse blocking voltage(VRB) and the forward blocking voltage(VFB). The drain-FP length, the gate-FP length and the passivation layer thickness were optimized. VRBand VFBwere improved from-67 V and 134 V to-653 V and 868 V respectively after optimization. Simulation results suggest that the combination of drain FP and Schottky drain can enhance the reverse blocking capability significantly. 相似文献
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Based on linear interval equations, an accurate interval finite element method for solving structural static problems with uncertain parameters in terms of optimization is discussed. On the premise of ... 相似文献
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本文通过沉积在多孔硅表面的银纳米粒吸附对氨基苯硫酚和氨基的化学转化得到终端为NiⅡ-Nα,Nα-二(羧甲基)-L-赖氨酸水合物-即 NiⅡ-NTA体系的芯片。NiⅡ-NTA修饰的芯片被用于从高浓度的盐和助溶剂的缓冲体系中亲和捕获组氨酸标记的融合蛋白:thioredoxin-urodilatin和SUMO-hu-aprotinin,并进行在线的MALDI-TOF质谱检测,克服了MALDI-TOF质谱中直接点样污染物妨碍样品与基质共结晶的问题,避免了繁琐的离线样品预处理。芯片在线分离、纯化和MALDI-TOF质谱分析体系有望在复杂或原始体液的溶液中分析目标分子。 相似文献
15.
Simulation design of normally-off AlGaN/GaN high-electron-mobility transistors with p-GaN Schottky hybrid gate 下载免费PDF全文
Yun-Long He 《中国物理 B》2022,31(6):68501-068501
A novel normally-off AlGaN/GaN high-electron-mobility transistor (HEMT) with a p-GaN Schottky hybrid gate (PSHG) is proposed, and compared with the conventional p-GaN normally-off AlGaN/GaN HEMTs. This structure can be realized by selective etching of p-GaN layer, which enables the Schottky junction and PN junction to control the channel charge at the same time. The direct current (DC) and switching characteristics of the PSHG HEMTs are simulated by Slivaco TCAD, and the p-GaN HEMTs and conventional normally-on HEMTs are also simulated for comparison. The simulation results show that the PSHG HEMTs have a higher current density and a lower on-resistance than p-GaN HEMTs, which is more obvious with the decrease of p-GaN ratios of the PSHG HEMTs. The breakdown voltage and threshold voltage of the PSHG HEMTs are very close to those of the p-GaN HEMTs. In addition, the PSHG HEMTs have a higher switching speed than the conventional normally-on HEMTs, and the p-GaN layer ratio has no obvious effect on the switching speed. 相似文献
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通过原位聚合法在金红石型纳米TiO2表面包覆硅烷偶联剂,研究超声波处理时间、水浴时间及溶液的pH值对改性效果的影响。结果表明:当超声时间为60min、水浴时间为2h、溶液的pH=6时,其改性效果最佳;采用扫描电镜、X射线衍射、差示扫描量热分析法、紫外-可见分光光度计、氧指数测试仪等手段对试样进行表征,结果显示:纳米TiO2与偶联剂之间的结合为化学结合,改性后的纳米粒子分散性得到了提高,当纳米TiO2添加量为3%时,PVC/KH570-TiO2复合材料的阻燃性能与机械性能最佳。 相似文献
17.
Improvement of reverse blocking performance in vertical power MOSFETs with Schottky–drain-connected semisuperjunctions 下载免费PDF全文
To enhance the reverse blocking capability with low specific on-resistance,a novel vertical metal-oxidesemiconductor field-effect transistor(MOSFET) with a Schottky-drian(SD) and SD-connected semisuperjunctions(SDD-semi-SJ),named as SD-D-semi-SJ MOSFET is proposed and demonstrated by two-dimensional(2D) numerical simulations.The SD contacted with the n-pillar exhibits the Schottky-contact property,and that with the p-pillar the Ohmic-contact property.Based on these features,the SD-D-semi-SJ MOSFET could obviously overcome the great obstacle of the ineffectivity of the conventional superjunctions(SJ) or semisuperjunctions(semi-SJ) for the reverse applications and achieve a satisfactory trade-off between the reverse breakdown voltage(BV) and the specific on-resistance(R_(on)A).For a given pillar width and n-drift thickness,there exists a proper range of n-drift concentration(N),in which the SD-D-semi-SJ MOSFET could exhibit a better trade-off of R_(on)A-BV compared to the predication of SJ MOSFET in the forward applications.And what is much valuable,in this proper range of N,the desired BV and good trade-off could be achieved only by determining the pillar thickness,with the top assist layer thickness unchanged.Detailed analyses have been carried out to get physical insights into the intrinsic mechanism of R_(on)A-BV improvement in SD-D-semi-SJ MOSFET.These results demonstrate a great potential of SD-D-semi-SJ MOSFET in reverse applications. 相似文献
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Structural Variation and Its Influence on the 1/f Noise of a-Si_(1-x)Ru_x Thin Films Embedded with Nanocrystals 下载免费PDF全文
The structural variation and its influence on the 1/f noise of a-Si_(1-x)Ru_x thin films are investigated by Raman spectroscopy,transmission electron microscopy, and low frequency noise measurement. The Ru atoms are introduced into the amorphous silicon thin films by rf magnetron co-sputtering. Ru2 Si nanocrystals are found in the as-deposited samples. It is shown that the 1/f noise of the films can be reduced by a slight doping with Ru atoms. Moreover, both the microstructure and the 1/f noise performance of a-Si_(1-x)Ru_x thin films could be improved through a high-temperature annealing treatment. 相似文献
20.
Cavity optomechanics: Manipulating photons and phonons towards the single-photon strong coupling 下载免费PDF全文
Cavity optomechanical systems provide powerful platforms to manipulate photons and phonons, open potential applications for modern optical communications and precise measurements. With the refrigeration and ground-state cooling technologies, studies of cavity optomechanics are making significant progress towards the quantum regime including nonclassical state preparation, quantum state tomography, quantum information processing, and future quantum internet. With further research, it is found that abundant physical phenomena and important applications in both classical and quantum regimes appeal as they have a strong optomechanical nonlinearity, which essentially depends on the single-photon optomechanical coupling strength. Thus, engineering the optomechanical interactions and improving the single-photon optomechanical coupling strength become very important subjects. In this article, we first review several mechanisms,theoretically proposed for enhancing optomechanical coupling. Then, we review the experimental progresses on enhancing optomechanical coupling by optimizing its structure and fabrication process. Finally, we review how to use novel structures and materials to enhance the optomechanical coupling strength. The manipulations of the photons and phonons at the level of strong optomechanical coupling are also summarized. 相似文献