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排序方式: 共有564条查询结果,搜索用时 46 毫秒
21.
22.
随着集成电路的集成度与性能的不断发展,芯片的功耗问题已经变的十分严重,功耗带来的挑战日益突出。异构多核动态调频架构是目前研究低功耗的主流方向。SOC系统当中同一时刻只有一个处理器能够控制总线,其它处理器则处理等待状态,异构多核动态调频架构能够通过降低不控制总线的处理器频率来达到降低功耗的目的。异构多核领域的处理器和总线跨时钟域解决方案,此方案在国内属于首次提出,可以运用在异构多核动态调频(DFS)架构当中。目前手持终端设备越来越强调功耗的重要性,因此异构多核领域的处理器和总线跨时钟域解决方案将有非常好的应用前景。该方案通过在处理器和AMBA总线之间添加FIFO以及一些复杂的算法,达到消除亚稳态和正常通信的目的。最终,通过仿真发现任意调节处理器的工作频率都能满足传输协议。证明该方案能在异构多核动态调频架构中运用。 相似文献
23.
We have compared the structure, microstructure, and electrochemical characteristics of xLi2MnO3–(1−x)Li(Mn0.375Ni0.375Co0.25)O2 (0.0 ≤ x ≤ 1.0) thin films with their bulk cathode laminate counterparts of identical compositions. Pure Li(Mn0.375Ni0.375Co0.25)O2 as well as the synthesized composite films partially transform into cubic spinel structure during charge–discharge cycling. In contrast, such layered to spinel phase transformation has only been identified in bulk cathode laminates with x ≥ 0.75. At a current density 0.05 mAcm−2, the discharge capacity of Li(Mn0.375Ni0.375Co0.25)O2 thin film was measured to be ∼60 μAhcm−2. The discharge capacity (∼217 μAhcm−2) was markedly improved in x∼0.5 composite thin film. The capacity retention after 20 charge discharge cycles are improved in composite films; however, their capacity fading could not be eliminated completely. 相似文献
24.
CO2-expanded liquid (CXL) is a mixture of organic solvent with high-pressure CO2 whose volume is increased by CO2 dissolved in it. CXLs have attracted attention as tunable solvents, because the solvent properties can be widely controlled by the pressure. The volume expansion and the solubility of CO2 were measured by near-infrared spectroscopy for 6 CXLs at various pressures up to 55 bar and 40 °C. The molarity of organic solvent was determined from the absorbance of the 3ν and 2ν + δ bands, and that of CO2 was obtained from the area of the 3ν3 band, whose peak shifted to higher frequency with increasing pressure due to a decrease in the molecular interaction around CO2. The expansion coefficient was shown to be an increasing function of the pressure with larger slope at higher pressure, and the mole fraction of CO2 in the liquid phase was an almost linearly increasing function of the pressure. The results were in quantitative agreement with the literature data measured by conventional sampling method, indicating the validity of the spectroscopic method. 相似文献
25.
The conversion of CO2 to useful chemicals, especially to atom economical products, is the best approach to utilize an excess of CO2 present in the atmosphere. In this study, a metal‐organic framework (ZIF‐8) is integrated with nanocrystalline zirconosilicate zeolite to develop an integrated porous catalyst for CO2 insertion reactions. The catalyst exhibits excellent activity for the CO2 insertion reaction of epoxide to produce cyclic carbonate in neat condition without the addition of any co‐catalyst. The catalyst is stable and recyclable during the cyclic carbonate synthesis. Further, the catalyst also exhibits very good activity in another CO2 insertion reaction to produce quinazoline‐2,4(1H, 3H)‐dione. 相似文献
26.
《Current Applied Physics》2020,20(4):582-588
Energy storage system powered by renewable energies is a viable option to meet energy requirement without addition of carbon footprints to the environment. This study involves development of theoretical and computational models for a solar photovoltaic (PV) system coupled with a lead acid battery. The study commenced with selection of most appropriate lead acid battery and PV system for installation in a representative location in Riyadh, Kingdom of Saudi Arabia. Various technical and economic parameters were assessed and calculated by computational approach. The optimized lead acid battery was integrated with low concentration solar PV panels (CPV) followed by a feasibility study. Theoretical model was developed for the integrated system to calculate various parameters of the CPV and lead acid battery. Technical and economic assessment of this coupled unit was calculated using a theoretical approach. The developed model was then subjected to computational approach for verification and validation analysis of the integrated system. The detailed assessment of batteries and integrated system show the applicability of this system in Riyadh region. The research will be extended to develop energy storage systems for remote areas using lead acid batteries. 相似文献
27.
离子色谱-积分脉冲安培检测法测定大蒜多糖的单糖组成 总被引:2,自引:1,他引:2
采用氨基酸分离柱(Amino PAC PA10,2×250 mm),用10.0 mmol/L NaOH溶液作为流动相,以Au为工作电极,Ag/AgCl为参比电极的脉冲积分安培离子色谱法,分离检测了大蒜多糖水解产生的单糖成分及相对含量。实验结果表明,大蒜多糖中含有半乳糖、葡萄糖、甘露醇和果糖,检出限在0.3~6μg/L范围,样品加标回收率为95%~112%。该法具有灵敏度高、精密度好、分离效果好和样品不需要衍生处理的优点,适用于各种植物多糖的单糖组成分析。 相似文献
28.
29.
Gabriela Molar-Velázquez Francisco J. Renero-Carrillo Wilfrido Calleja-Arriaga 《Optik》2010,121(9):843-846
A two-dimensional optical micro-scanner, which main components are two mobile flat and a concave micro-mirrors, is designed such that, all optical components can be fabricated on the same substratum. The optical parameters, which physical dimensions are between 50 and 500 μm, are obtained within the geometrical optics. The optical performance is evaluated by means of the MTF and Rayleigh resolution criteria, given 80% of modulation for a frequency of 8 cycles/mm with a Gaussian source, the resolution limit is 30 μm. 相似文献
30.
A novel plasmonic nanolens formed by a tapered subwavelength metal slit surrounded by surface dielectric gratings is proposed and demonstrated numerically. By patterning surface corrugations on the output surface, the beam can be focused, by regulating the aperture, the focal length can be controlled effectively. Numerical simulations using Finite-Difference Time-Domain (FDTD) method coupled with anisotropic perfectly matched layer (APML) boundary conditions verify that the proposed metallic lens can focus the radiation on the scale of a wavelength below the substrate and the method is effective for the design of nano-optical devices such as optical microprobes. 相似文献