摘要：Understanding the influence of purities on the electrochemical performance of pure aluminum(Al)in alkaline media for Al–air batteries is ***,we comprehensively investigate secondary phase precipitate(SPP)-induced localized corrosion of pure Al in NaOH solution mainly based on quasi-in-situ and cross-section observations under scanning electron microscopy coupled with finite element *** experimental results indicate that Al–Fe SPPs appear as clusters and are coherent with the Al *** alkaline media,Al–Fe SPPs exhibit more positive potentials than the substrate,thus aggravating localized galvanic corrosion as cathodic ***,finite element simulation indicates that the irregular geometry coupled with potential difference produces the non-uniform current density distribution inside the SPP cluster,and the current density on the Al substrate gradually decreases with distance.

摘要：With a lot of millimeter-wave(mm-Wave)applications being issued,wideband circuits and systems have attracted much attention because of their strong applicability and *** this paper,four transformer-based ultra-wideband mm-Wave circuits demonstrated in CMOS technologies are reviewed from theoretical analysis,implementation,to ***,we introduce a mm-Wave low-noise amplifier with transformer-based Gm-boosting and pole-tuning *** achieves wide operating bandwidth,low noise figure,and good gain ***,we review an injection-current-boosting technique which can significantly increase the locking range of mm-Wave injection-locked frequency *** on the injectionlocked principle,we also discuss an ultra-wideband mm-Wave divider with the transformer-based high-order ***,an E-band up-conversion mixer is presented;using the two-path transconductance stage and transformer-based load,it obtains good linearity and a large operating band.

摘要：动态调控是现代光学器件中必不可少的特性,在激光雷达系统、显示器件以及数码相机等设备中具有重要意义.与传统的体光学器件相比,动态超表面为实现小型化和集成化智能光学系统提供了一个极具吸引力的解决方案.相变材料具有高的折射率对比度和易于操控的特性,是设计动态超表面的理想材料.本文通过操控氧化钒的相变,在近红外区域设计实现了可调谐的超构透镜和可切换图像编码的超表面器件.通过控制氧化钒的相变,能够改变超透镜的聚焦强度,实现强度对比约为12倍的开关聚焦效果.此外,利用氧化钒的相变还设计实现了任意两个不同数字图案的可切换成像.本工作为实现动态成像和光学加密系统的可调谐超表面奠定了基础.

摘要：Lorenz 系统家庭统一 Lorenz 系统，陈系统和 L ü系统是一个典型混乱家庭。在这篇论文，我们与变化时间的推动间隔认为冲动的控制是 Lorenz 混乱系统家庭。由建立一套不平等的一个有效工具，我们分析冲动的控制 Lorenz 系统家庭的 asymptotic 稳定性并且获得一些新不太保守的条件。基于稳定性分析，我们与变化时间的推动间隔设计一个新奇冲动的控制器。解说性的例子被提供显示出我们的方法的可行性和有效性。获得的结果能不仅被用来为 Lorenz 系统家庭设计冲动的控制，而且能被扩大到另外的混乱系统。

摘要：The use of a reconfigurable intelligent surface(RIS)in the enhancement of the rate performance is considered to involve the limitation of the RIS being a passive *** address this issue,we propose a RIS-aided amplify-and-forward(AF)relay network in this *** jointly optimizing the beamforming matrix at AF relay and the phase-shift matrices at RIS,two schemes are put forward to address a maximizing signal-to-noise ratio(SNR)***,aiming at achieving a high rate,a high-performance alternating optimization(AO)method based on Charnes–Cooper transformation and semidefinite programming(CCT-SDP)is proposed,where the optimization problem is decomposed into three subproblems solved using CCT-SDP,and rank-one solutions can be recovered using Gaussian ***,the optimization variables in the CCT-SDP method are matrices,leading to extremely high *** reduce the complexity,a low-complexity AO scheme based on Dinkelbachs transformation and successive convex approximation(DT-SCA)is proposed,where the variables are represented in vector form,and the three decoupling subproblems are solved using *** results verify that compared to three benchmarks(i.e.,a RIS-assisted AF relay network with random phase,an AF relay network without RIS,and a RIS-aided network without AF relay),the proposed CCT-SDP and DT-SCA schemes can harvest better rate ***,it is revealed that the rate of the low-complexity DT-SCA method is close to that of the CCT-SDP method.

摘要：A gallium nitride(GaN)power amplifier monolithic microwave integrated circuit(MMIC)with a wide band and high efficiency in the microwave frequency band is proposed in this *** power amplifier MMIC uses a 0.15^im GaN high electron mo-bility transistor(HEMT)*** operating frequency band of the amplifier can cover the whole K-band,i.e.,17-26.5 GHz.

摘要：A novel tunable optical power splitter, with a Y-branch waveguide based on the total internal reflection and a microprism with tunable index refraction, is presented. Numerical simulation of its optical performance shows that a high dynamic range, low optical loss, and relatively low wavelength-dependence can be achieved. This component offers numerous advantages such as ease for fabrication, low cost, and compact size, which are very useful for potential application in integrated optical devices.

摘要：To meet the requirements of the low power Zigbee system, VCO design optimizations of phase noise, power consumption and frequency tuning are discussed in this paper. Both flicker noise of tail bias transistors and up-conversion of flicker noise from cross-coupled pair are reduced by improved self-switched biasing technology, leading to low close-in phase noise. Low power is achieved by low supply voltage and triode region biasing. To linearly tune the frequency and get constant gain, distributed varactor structure is adopted. The proposed VCO is fabricated in SMIC 0.18-#m CMOS process. The measured linear tuning range is from 2.38 to 2.61 GHz. The oscillator exhibits low phase noise of-77.5 dBc/Hz and -122.8 dBc/Hz at l0 kHz and 1 MHz offset, respectively, at 2.55 GHz oscillation frequency while dissipating 2.7 mA from 1.2 V supply voltage, which well meet design specifications.

摘要：本文提出一种用于在干扰被视为加性高斯噪声的假设下在Z干扰信道(z-interference channel,Z-IC)上实现非正则高斯信号(IGS)的Pareto边界(可实现速率区域的边界)。具体来说,文章表明了帕累托边界可由某个用户的传输速率的两个区域表征,由传输信号的方差与伪协方差的两个变化路径决定。为每个用户发送的非正则信号的最优协方差和伪协方差设计推导出简明闭合的表达式。为此,我们通过仿真试验有力证明了所提出的最优信号设计策略的有效性,同时直观地展现出IGS较正则高斯信号(proper Gaussian signaling,PGS)的优越性。此外,我们提出的最优信号设计策略提供了实现所需速率区域的简单方法。利用该方法,我们得到了一个闭合形式的解决方案,用于快速确定最大和速率的信号设计方案。最后,我们深入讨论了帕累托边界的特征,定性分析了信道系数以及两个用户发送的信号的协方差和伪协方差与其的关系。

摘要：In this paper, we present a design where a bunched relativistic electron beam traversing inside the rectangular dielectric-loaded （DL） waveguide is used as a high power microwave generation device. Two kinds of methods of calculating the electromagnetic （EM） field excited by a bunched beam are introduced, and in the second method the calculation of EM pulse length is discussed in detail. The desired operating mode is the LSM11 due to its strong interaction with the electron beam. For the designed 7.8 GHz operating frequency, with a 100 nC/bunch drive train of electron bunches separated by 0.769 ns, we find that high gradient （〉 30 MV/m） and high power （〉 160 MW） can be generated. An output coupler is also designed which is able to extract the generated power to standard waveguides with a 94% coupling efficiency.