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51.
53.
With the development of MEMS and the electronic devices's miniaturization and integration, a new kind of power sources that can satisfy the need for high energy density is required. Microbatteries are being researched abroad for their advantages of extreme thinness and long-term power supply. The development of MEMS microbatteries are reviewed and suggestedmagnetron sputtering in fabricating a high-performance microbattery. The technics as annealing are analyzed. The microbattery with a LiNi1-x Cox O2 cathode exhibited stable cycle ability and a high specific discharge capacity, which was attributed to the alloying effect of the LiNiO2and LiCoO2. 相似文献
54.
Donglin He Ping Li Wei Wang Qi Wan Jian Zhang Kai Xi Xiumei Ma Zhiwei Liu Lin Zhang Xuanhui Qu 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(5)
Although silicon‐based materials are ideal candidate anodes for high energy density lithium‐ion batteries, the large volumetric expansion seriously damages the integrity of the electrodes and impedes commercial processes. Reasonable electrode design based on adjustable structures of silicon and strong binders prepared by a facile method is still a great challenge. Herein, a three‐pronged collaborative strategy via hollow nanocubes, amorphous Void@SiOx@C, and in situ cross‐linked polyacrylic acid and d ‐sorbitol 3D network binder (c‐PAA‐DS) is adopted to maintain structural/electrode integrality and stability. The all‐integrated c‐PAA‐DS/Void@SiOx@C electrode delivers excellent mechanical property, which is attributed to ductility of the c‐PAA‐DS binder and high adhesion energy between Void@SiOx@C and c‐PAA‐DS calculated by density functional theory. Benefiting from the synergistic effect of accommodation of the hollow structure, protection of outer carbon shell, amorphous Void@SiOx@C, and strong adhesive c‐PAA‐DS binder, c‐PAA‐DS/Void@SiOx@C shows excellent electrochemical performance. Long cycling stability with a reversible capacity of 696 mAh g?1 is obtained, as well as tiny capacity decay after 500 cycles at 0.5 A g?1 and high‐rate performance. The prelithiated Void@SiOx@C||LiNi0.5Co0.2Mn0.3O2 (NCM523) full cell is also assembled and shows a reversible capacity of 157 mAh g?1 at 0.5 C, delivering an excellent capacity retention of 94% after 160 cycles. 相似文献
55.
理论上通过篡改FPGA位流,利用其实现的密码算法的错误输出可以分析出密钥,但这种攻击通常需要非常了解目标FPGA的内部结构与位流的对应关系。而位流逆向的难度很大,导致此类攻击的实用性不高。文章提出一种针对FPGA位流的自动化故障注入分析方法,不需要逆向位流,结合张帆等人提出的持久性故障分析理论,把因篡改算法常量导致的出错结果作为可利用的故障。并首次在Xilinx-7系列FPGA开发板上利用Spider进行电压故障注入实验,480条错误密文就可以得到AES-128的密钥,且在10 min内可以完成数据的采集和分析。对于加密位流的情况,可以先利用电磁侧信道分析方法得到明文位流,再结合该文的分析方法来进行密钥破解。 相似文献
56.
梅山汽车运输分公司运翔码头原设计为1500吨级码头,为适应市场发展需要,要停靠5000吨级船舶。从现运翔码头前沿航行水深、码头设施、防护设施等实际出发对安全停靠5000吨级船舶进行可行性论证。 相似文献
57.
Ping Huang Guangwei Chen Weifeng Jin Kunjun Mao Haitong Wan Yu He 《International journal of molecular sciences》2022,23(13)
Differential evolution of apoptosis, programmed necrosis, and autophagy, parthanatos is a form of cell death mediated by poly(ADP-ribose) polymerase 1 (PARP1), which is caused by DNA damage. PARP1 hyper-activation stimulates apoptosis-inducing factor (AIF) nucleus translocation, and accelerates nicotinamide adenine dinucleotide (NAD+) and adenosine triphosphate (ATP) depletion, leading to DNA fragmentation. The mechanisms of parthanatos mainly include DNA damage, PARP1 hyper-activation, PAR accumulation, NAD+ and ATP depletion, and AIF nucleus translocation. Now, it is reported that parthanatos widely exists in different diseases (tumors, retinal diseases, neurological diseases, diabetes, renal diseases, cardiovascular diseases, ischemia-reperfusion injury...). Excessive or defective parthanatos contributes to pathological cell damage; therefore, parthanatos is critical in the therapy and prevention of many diseases. In this work, the hallmarks and molecular mechanisms of parthanatos and its related disorders are summarized. The questions raised by the recent findings are also presented. Further understanding of parthanatos will provide a new treatment option for associated conditions. 相似文献
58.
Viewed as sinews and muscles of fluid motion,coherent vortical structures with their interactions are key to understanding the flow dynamics.Based upon this observation,we explore the possibility of efficient flow control by directly manipulating vortices numerically inside the flow field based on the vortex definition and identification system of Liutex.The objective is twofold:(1)to study the vortex dynamics,for example,by observing the response of the flow to strengthening or weakening of certain vortices,and(2)to obtain efficient vortex-based control strategies which might lead us to practical applications.In the present numerical study,the manipulating of vortices is achieved by introducing additional source(force)terms to the Navier-Stokes equations,which hereafter will be collectively called Liutex force field model.Methodologies including controlling the rotation strength and centripetal force of particular vortices are detailed in a flow past a cylinder with different control purposes at Reynolds number of 200.Further examples are provided with a cavitating flow around two-dimensional Clark-Y hydrofoil,with particular interests on cavitation suppression.It is illustrated particular vortex with cavitation encircled could be effectively suppressed. 相似文献
59.
Most existing two dimensional(2-D)angles of arrival(AOAs)estimation methods are based on the assumption that the signal sources are point sources.However,in mobile communications,local scattering in the vicinity of the mobile results in angular spreading as seen from a base station antenna array.In this paper,we consider the problem of estimating the 2-D AOAs of spatially distributed sources.First we perform blind estimation of the steering vectors by exploiting joint diagonalization,then the 2-D AOAs are obtained through two fast Fourier transforming of the estimated steering vectors.Simulations are carried out to illustrate the performance of the method. 相似文献
60.
湍流大气中光强闪烁对光通信链路的影响 总被引:4,自引:0,他引:4
给出了用大气传输通信设备进行传输距离 3.4 km外场试验光强闪烁对光通信链路影响的实验结果 ,并简要分析了光强闪烁对信号检测的影响和误码原因 相似文献