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1.
讨论了全空间上一类带Hardy-Sobolev项的拟线性椭圆问题,利用集中紧原理和适当的实验函数,得到并验证了(PS)_c条件,从而证明了该问题非平凡解的存在性.  相似文献   
2.
该文研究了一类带临界指标的Neumann问题, 利用Pohozaev恒等式和一些好的估计, 得到了此类问题解的唯一性结果.  相似文献   
3.
文献调研国外核动力航空推进相关技术研究,美国GE与PW公司通过ANP计划已试验验证了核动力航空推进的可行性;分析认为核动力航空推进当前最佳用途是长航时无人机与巡航导弹动力,关键技术是核屏蔽的轻量化设计、热交换效率与速率、热力系统设计与新型结构问题;核动力航空推进若采用蒸汽介质的二回路闭式循环驱动螺旋桨,蒸汽透平及动力系统设计没有技术障碍,闭式循环蒸汽流量关键取决于蒸汽透平汽耗率与热交换循环时间。  相似文献   
4.
The strain impact on hole mobility in the GOI tri-gate pFETs is investigated by simulating the strained Ge with quantum confinement from band structure to electro-static distribution as well as the effective mobility. Lattice mismatch strain induced by HfO2 warps and reshapes the valence subbands, and reduces the hole effective masses. The maximum value of hole density is observed near the top comers of the channel. The hole density is decreased by the lattice mismatch strain. The phonon scattering rate is degraded by strain, which results in higher hole mobility.  相似文献   
5.
采用水热法合成了2个铁的过渡金属配位聚合物[Fe(Medpq)(BDC)H2O]n(1)和{[Fe(Medpq)(QUI)H2O]·2H2O}n(2)(Medpq=2-methyldipyrido[3,2-f:2',3'-h]quinoxaline; H2BDC=terephthalic acid; H2QUI=2,3-pyridinedicarboxylic acid),并对其进行了元素分析、红外光谱和热重表征,并用X射线单晶衍射测定结构。2个配位聚合物中的中心铁(Ⅱ)离子,都呈现一个稍微扭曲的八面体几何构型。  相似文献   
6.
We have evaluated the effects of recombination processes in a charge storage layer, either between trapped electrons and trapped holes or between trapped carriers and free carriers, on charge trapping memory cell's performances by numerical simulation. Recombination is an indispensable mechanism in charge trapping memory. It helps charge convert process between negative and positive charges in the charge storage layer during charge trapping memory programming/erasing operation. It can affect the speed of programming and erasing operations.  相似文献   
7.
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   
8.
彭雅华  刘晓彦  杜刚  刘飞  金锐  康晋锋 《中国物理 B》2012,21(7):78501-078501
We evaluate the influence of the thermally assisted tunneling (TAT) mechanism on charge trapping memory (CTM) cell performance by numerical simulation, and comprehensively analyse the effects of the temperature, trap depth, distribution of trapped charge, gate voltage and parameters of TAT on erasing/programming speed and retention performance. TAT is an indispensable mechanism in CTM that can increase the detrapping probability of trapped charge. Our results reveal that the TAT effect causes the sensitivity of cell performance to temperature and it could affect the operational speed, especially for the erasing operation. The results show that the retention performance degrades compared with when the TAT mechanism is ignored.  相似文献   
9.
In this paper,we investigate the performance of the bulk fin field effect transistor(FinFET) through a threedimensional(3D) full band Monte Carlo simulator with quantum correction.Several scattering mechanisms,such as the acoustic and optical phonon scattering,the ionized impurity scattering,the impact ionization scattering and the surface roughness scattering are considered in our simulator.The effects of the substrate bias and the surface roughness scattering near the Si/SiO2 interface on the performance of bulk FinFET are mainly discussed in our work.Our results show that the on-current of bulk FinFET is sensitive to the surface roughness and that we can reduce the substrate leakage current by modulating the substrate bias voltage.  相似文献   
10.
航空发动机空气系统需要从多级轴流压气机中间级引气,不同引气方式将对轴流压气机性能和流场产生不同影响.以一带进口导叶的单级轴流压气机为研究对象,采用数值模拟方法研究了全周开缝、均布开孔以及不同开孔角度等引气方式对压气机性能的影响.结果表明,引气可不同程度地提高压气机性能,沿流向倾斜开设引气孔使喘振裕度提升最大,达到8.2%,反流向开设引气孔使压气机效率、压比有较大提高.  相似文献   
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