有机层界面对双层有机发光二极管复合效率的影响

建立了双层有机发光二极管中载流子在有机层界面复合的无序跳跃理论模型.由于有机分子材料的空间及能带结构的无序性，采用刚体模型处理有机层界面问题是不恰当的，而采用无序跳跃模型比较合理.复合效率及复合电流由载流子跳跃距离、有机层界面的有效势垒高度及该界面处的电场强度分布所决定：在双层器件ITO/α-NPD/Alq₃/Al中，当所加电压小于19.5V时，复合效率随着载流子跳跃距离的增加而增加，而大于19.5V时，复合效率随着其距离的增加而减少；复合效率随着有机层界面有效势垒高度的增加而增加； 关键词： 有机层界面 双层有机发光二极管 复合效率 有效势垒高度 无序跳跃模型     

混合层中柱状粒子运动的研究

本文在直接数值模拟混合层流场的基础上,求解柱状粒子运动方程而得到粒子运动轨迹,说明粒子在混合层中的不同区域,其运动轨迹也不同,有的呈现波状轨迹,有的呈现环状轨迹,有的是混合轨迹。粒子的混合程度与St数有关。文中结论对工程应用有指导意义。     

Influence of the metallic absorption layer on the quality of thermal conductivity measurements by the transient thermo-reflectance method

This work investigates numerically the influence of a metallic absorption layer on the laser-based measurements of the thermal conductivity of dielectric (SiO₂) and semiconductor (Si) electronic materials. The validity of the approach and the obtained results are assessed by comparison with experimental measurements obtained for gold-covered silicon dioxide samples. The results reveal the presence of behaviors associated with thermally thin and thermally thick absorption layers, depending on the ratio between the thickness of the absorption layer and the heat penetration depth. Optimal performance of the transient thermo-reflectance method was found to exist for thicknesses of metal layers falling between the identified thermally thin and thermally thick layers.     

Gas-Dynamic Methods of Temperature Stratification (a Review)

The known methods of gas-dynamic temperature stratification are reviewed. Attention is concentrated on an analysis of the possibilities of the gas dynamic stratification method proposed by the author. The method is based on the difference between the equilibrium temperature of a thermally insulated wall in supersonic flow and the adiabatic stagnation temperature of the gas. Certain possible practical applications of the method to various types of energy-converting apparatus are considered. The basic trends of fundamental and applied research in the field of gas-dynamic temperature stratification are formulated.     

MULTIPLE BOUNDARY LAYER PHENOMENA OF THE SOLUTION OF NONLINEAR HIGHER ORDER ELLIPTIC EQUATIONS WITH PERTURBATION BOTH IN BOUNDARY AND IN OPERATOR

1IntroductionInmanyproblemsofmechanicsandphysics,therefrequentlyappeartheellipticequationswiththederivativetermofthehigherordercontainingsmallparameters.Inengineering,thehigherorderellipticequationswithbothboundaryperturbationandoperatorperturbationoccurintheproblemsofcircularorellipticcoluxnnarshell(suchasthehullofasubmarineorthecolumnarshellroofetc.)withstiffeningribinthecirculnferentialdirection.Insuchcasesjthestudyofweldingstresscausedbyexternalpressureorself-weightduetoabnormalweldingposi…     

钩藤中异钩藤碱在TLC原位的FT-SERS研究

本文报道了将薄层色谱（TLC）与傅里叶变换表面增强拉曼散射（FT－SERS）联用，获得了中草药钩藤中的异钩藤碱光谱研究的新方法。研究表明，在薄层原位，2.5μg钩藤总碱可将异钩藤碱等8种生物碱完全分离。应用薄层原位的薄层色谱傅里叶变换表面增强拉曼散射（TLC－FT－SERS）技术，获得异钩藤碱分子的特征振动谱带，进而阐述了样品分子在银胶表面的吸附模式，异钩藤碱以分子中氧化吲哚基团上N原子的孤子电子对和吲哚环π电子共同吸附于银晶体微粒表面,1.615cm^-1与芳环骨架振动和氧化吲哚N－H变形振动相关的峰获得最大增强。说明TLC－FT－SERS对中草药化学成分进行高灵敏度示踪指纹检测的可靠性和优越性。     

宽带VPDN技术及其在城域网中的应用研究

简单介绍了宽带VPDN业务，分析了宽带VPDN基本原理及其在宽带IP城域网上的基本应用模式，并介绍了在宽带IP城域网上进行的宽带VPDN试验情况。     

ADSL网络体系结构

ADSL是DSL的一种非对称版本，是目前一种重要的宽带接入方式，ADSL能够向终端用户提供8Mbit/s的下行传输速率和1Mbit/s的上行传输速率，比传统的28．8kbit/s模拟调制解调器快将近200倍。文中讨论了一组能够支持基于PPP／ATM／ADSL接入网体系结构的核心网体系结构，分析了几种不同组网方式的特征与协议栈模型。     

New Oligomeric Proanthocyanidine from Ziziphus jujuba

Chemical and spectral data establish the structure of an oligomeric proanthocyanidine PZ-5 isolated from Ziziphus jujuba.     

由等价掺杂转换理论得到非对称线性缓变P-N结的击穿特性

基于等价掺杂转换理论的应用,得到了解析计算非对称线性缓变P-N结击穿特性.由于非对称线性缓变P-N结是单扩散P-N结的一个恰当近似,因而,研究其击穿特性可以更好地理解和设计功率器件P-N结的终端结构.运用等价掺杂转换方法的基本理论得到了不同扩散掺杂梯度和衬底浓度组合系列的击穿电压.研究了最大耗尽层宽度在扩散侧和衬底侧的扩展,给出了它们随扩散掺杂梯度和衬底浓度组合的变化而出现的不同特点.本方法预言的最大击穿电压较之单纯的突变结和对称线性缓变P-N结更接近文献报道的结果,显示了等价掺杂转换理论的理论计算非对称线性缓变P-N结击穿电压的有效性.