Effects of Strain Rate,Temperature and Grain Size on the Mechanical Properties and Microstructure Evolutions of Polycrystalline Nickel Nanowires: A Molecular Dynamics Simulation

Through molecular dynamics(MD)simulation,the dependencies of temperature,grain size and strain rate on the mechanical properties were studied.The simulation results demonstrated that the strain rate from 0.05 to 2 ns~(–1 )affected the Young’s modulus of nickel nanowires slightly,whereas the yield stress increased.The Young’s modulus decreased approximately linearly;however,the yield stress firstly increased and subsequently dropped as the temperature increased.The Young’s modulus and yield stress increased as the mean grain size increased from 2.66 to6.72 nm.Moreover,certain efforts have been made in the microstructure evolution with mechanical properties association under uniaxial tension.Certain phenomena such as the formation of twin structures,which were found in nanowires with larger grain size at higher strain rate and lower temperature,as well as the movement of grain boundaries and dislocation,were detected and discussed in detail.The results demonstrated that the plastic deformation was mainly accommodated by the motion of grain boundaries for smaller grain size.However,for larger grain size,the formations of stacking faults and twins were the main mechanisms of plastic deformation in the polycrystalline nickel nanowire.     

Reconsideration on Homogeneous Quadratic Riemann Boundary Value Problem

The homogeneous quadratic Riemann boundary value problem (1) with Hoelder continuous coefficients for the normal case was considered by the author in 1997. But the solutions obtained there are incomplete. Here its general method of solution is obtained.     

浅谈功率因数的补偿及其应用

根据我国当前电力系统运行情况，对电网无功功率补偿的必要性及通用补偿方法及其装置进行了具体阐述。     

顶凌覆盖节水增产技术研究

通过1998年、2000年的试验研究，系统分析了顶凌覆盖技术在高寒区节水增温保温、增产增收的机理及其应用效果。提出该技术可以缓解低温干旱特别是春旱对农业生产的困扰，是一项可以抗旱保春播增产增收的实用技术，在高寒地区具有较高的推广价值。     

复数,实数及实对称数据下Bruun FFT算法的实现

本文在复数、实数以及实对称数据下研究和实现了Ｂｒｕｕｎ ＦＦＴ算法。文章分析和评价了各种数据下ＢｒｕｕｎＦＦＴ的运算量和特点，提出了算法的实现结构和方法。最后给了ＴＭＳ３２０Ｃ３０上的运算时间，我们实现的算法比基２ＦＦＴ速度提高３５％。     

Influence of Microstructure and Sintering Routes on Transport Properties of Apatite Materials for Fuel Cells

1 Results Oxy-apatite materials are thought as zirconia-substitutes in Solid Oxide Fuel Cells due to their fast ionic conduction. However, the well known difficulties related to their densification prevent them from being used as such. This study presents strategies to obtain oxy-apatite dense materials and the influence of elaboration route on transport properties. Particular emphasis is put on the microstructure effect on ion conduction. By the combined use of freeze-drying and conventional or spark p...     

Static extracting method of software intended behavior based on API functions invoking

The method of extracting and describing the intended behavior of software precisely has become one of the key points in the fields of software behavior＇s dynamic and trusted authentication. In this paper, the author proposes a specified measure of extracting SIBDS （software intended behaviors describing sets） statically from the binary executable using the software＇s API functions invoking, and also introduces the definition of the structure used to store the SIBDS in detail. Experimental results demonstrate that the extracting method and the storage structure definition offers three strong properties： （i） it can describe the software＇s intended behavior accurately; （ii） it demands a small storage expense; （iii） it provides strong capability to defend against mimicry attack.     

Homology Priority Task Scheduling in μC/OS-Ⅱ Real-Time Kernel

μC/OS-Ⅱ is an open source real-time kernel adopting priority preemptive schedule strategy. Aiming at the problem of μC/OS-Ⅱ failing to support homology priority tasks scheduling, an approach for solution is proposed. The basic idea is adding round-robin scheduling strategy in its original scheduler in order to schedule homology priority tasks through time slice roundrobin. Implementation approach is given in detail. Firstly, the Task Control Block （TCB） is extended. And then, a new priority index table is created, in which each index pointer points to a set of homology priority tasks. Eventually, on the basis of reconstructing μC/OS-Ⅱ real-time kernel, task scheduling module is rewritten. Otherwise, schedulability of homology task supported by modified kernel had been analyzed, and deadline formula of created homology tasks is given. By theoretical analysis and experiment verification, the modified kernel can support homology priority tasks scheduling, meanwhile, it also remains preemptive property of original μC/OS-Ⅱ.