Characterization of metal/GaN Schottky interfaces based on I–V–T characteristics

Interface properties of metal/n- and p-GaN Schottky diodes are studied by I–V–T and C–V–T measurements, and simulation of their characteristics. On the basis of the previously proposed “surface patch” model, the gross behavior of I–V–T characteristics, which includes Richardson plots together with temperature dependence of the effective Schottky barrier heights (SBHs) and n-values, can be well reproduced. Furthermore, the dependence of the true SBH on the metal work function was also deduced from high-temperature I–V curves, giving S-values of 0.28 and 0.20 for n- and p-GaN samples, respectively, and the interface Fermi level tends to be pinned at a characteristic energy of about two-third of the bandgap.     

MPDATA: A Finite-Difference Solver for Geophysical Flows

This article is a review of MPDATA, a class of methods for the numerical simulation of fluid flows based on the sign-preserving properties of upstream differencing. MPDATA was designed originally as an inexpensive alternative to flux-limited schemes for evaluating the advection of nonnegative thermodynamic variables (such as liquid water or water vapour) in atmospheric models. During the last decade, MPDATA has evolved from a simple advection scheme to a general approach for integrating the conservation laws of geophysical fluids on micro-to-planetary scales. The purpose of this paper is to summarize the basic concepts leading to a family of MPDATA schemes, to review existing MPDATA options, and to demonstrate the use of MPDATA to effectively construct two distinct types of models (elastic and anelastic) for complex geophysical flows.     

计算机模拟研究聚合物纳米复合材料的分散与界面

针对聚合物纳米复合材料,系统综述了计算机模拟技术(分子动力学模拟)在纳米颗粒的分散与聚合物-纳米颗粒界面作用取得的成果与进展,包括不同形状纳米颗粒在聚合物基体的分散机理、相行为与微观结构、纳米颗粒对分子链构象的影响(分子链均方回转半径的变化)、分子链在纳米颗粒表面结构(取向与排列)、分子链与纳米颗粒界面作用能、界面区分子链活动性与纳米颗粒形成的网络结构.为构建聚合物纳米复合材料的组成、结构与性能之间的关系,提出了3个模拟方面的挑战,包括发展长时间跨尺度计算机模拟技术、建立准确模拟材料力学性能的方法与导电导热功能性的模拟.     

基于LabVIEW和GPIB的数字示波器数据自动采集系统设计

介绍了一种利用数字示波器和工控机建立的数据自动采集系统。通过GPIB接口,用一台工控机对多台数字示波器进行控制,实现对信号数据的采集、处理并将处理结果存入数据库中。采用这种方法建立的系统简单、经济、通用性强,具有一定的实用价值。     

Fisher–KPP equation with advection on the half‐line

We consider the Fisher–KPP equation with advection: u_t=u_xx?βu_x+f(u) on the half‐line x∈(0,∞), with no‐flux boundary condition u_x?βu = 0 at x = 0. We study the influence of the advection coefficient ?β on the long time behavior of the solutions. We show that for any compactly supported, nonnegative initial data, (i) when β∈(0,c₀), the solution converges locally uniformly to a strictly increasing positive stationary solution, (ii) when β∈[c₀,∞), the solution converges locally uniformly to 0, here c₀ is the minimal speed of the traveling waves of the classical Fisher–KPP equation. Moreover, (i) when β > 0, the asymptotic positions of the level sets on the right side of the solution are (β + c₀)t + o(t), and (ii) when β≥c₀, the asymptotic positions of the level sets on the left side are (β ? c₀)t + o(t). Copyright © 2016 John Wiley & Sons, Ltd.     

界面改性对玻纤增强聚丙烯弯曲强度的影响

为了提高玻纤增强聚丙烯（ＰＰ）的界面粘结，分别用Ｂ３０１或硅烷偶联剂对玻纤表面进行了处理，用过氧化物和顺丁烯二酸酐对ＰＰ进行了改性。经处理和改性后，ＰＰ／ＧＦ复合材料的弯曲强度有明显提高，对玻纤增强聚丙烯的界面结构也作了探讨。     

STUDY ON THE FORMATIONAL MECHANISM OF THE NORTHERN YELLOW (Huanghai) SEA COLD WATER MASS (Ⅱ)——DISCUSSION ON THE SOLUTION OF THE MODEL

The theoretical solution of the model of the Northern Yellow (Huanghai) Sea Cold Water Mass (NYSCWM) reveals that the NYSCWM is mainly formed through the continuous temperature increase of the overwintered water body above the Northern Yellow Sea Depression (NYSD) after spring when heat is continuously conducted from the sea surface to the'deeper layer. In the NYSCWM's growing period, (June-July), nonlinear, vertical convection and advection effects continuously increase, and are gradually balanced by the heat diffusion effect as the temperature increases from the surface to the bottom, which leads to the formation of an intensive thermocline and lateral front. Meanwhile, the three-dimensional circulation correspondingly occurs. In the NYSCWM's entire growing period, the horizontal circulation is always in the cyclonic motion, while the vertical circulation passes through a transition from a period with the cold centre as downwelling to a period with the cold centre as upwelling.     

等离子体处理云母对填充聚烯烃结构影响的研究

<正> 近年出现的用冷等离子体处理填料的方法被认为是偶联剂技术的一个新发展。它是通过等离子体作用,使填料表面产生有利于与基体树脂相容的结构变化,从而实现改善填充体系使用和加工性能的目的。这种处理方法具有作用强度大而穿透力小、效率高,无公害等特点。与采用硅烷、钛酸酯偶联剂等较成熟的处理方法不同,等离子体处理的研究尚在起步阶段,基本局限于对处理效果的探讨,有关处理对填充体系结构影响的研究尚不多见。本文以经乙烯等离子体处理的云母为填料,初步研究了填料与HDPE、IDPE及PS界面的水扩散特性、界面极化特性,以及基体的松弛转变行为。     

Ti/ZrN2/Si薄膜界面扩散反应的研究

利用直流磁控反应溅射法在Si基底上制备了Ti/ZrN2/Si多层薄膜，利用俄歇深度剖析和线形分析研究了真空热处理前后膜层间的界面状态及相互作用.研究结果表明，Ti膜和ZrN2膜均在沉积过程中发生了界面扩散作用，真空热处理可以显著地增强Ti/ZrN2/Si膜层间的界面扩散和化学反应，并分别在界面层生成了TiNx和SiNx等物种.