Theoretical Research on a Kind of Quantum Left-handed Metamaterial

Recently, research on left-handed materials （LHMs） has attracted considerable attentions. The LHMs are a kind of metameterial which have negative permittivity and negative permeability, which lead to negative refractive index in a frequency range. The LHMs that have been available so far are in the microwave range and are usually composed of classical particles, such as split-ring resonators. Some quantum phenomena such as spontaneous emission of atoms in the LHMs which are considered to be ＇classical background＇ have also been investigated. Many potential applications of LHMs have been proposed, such as superlenses which, in principle, can achieve arbitrary subwavelength resolution.     

钢板仓受风载作用的有限元分析

对高 14.76m ,直径 12m的螺旋卷边钢板筒仓在空仓风载工况下进行了有限元分析。计算结果表明 ,在风载作用下 ,仓体的强度不是主要问题 ,而仓顶开口处刚度较弱。     

关于命题公式的主范式

本文讨论了两个命题公式的一次复合的主析(合)取范式与它们的主析(合)取范式之间的关系。     

大众文化在中国的阐释焦虑

随着中国改革开放的进一步深化，大众文化得以20世纪90年代的中国大地上迅速兴起和发展。面对大众文化这一新的社会文化现象，理论的阐释面临着危机。当前对大众文化的分析研究出现和阐释的焦虑，主要表现在两个方面：一是研究者对大众文化持有各种不同的乃至完全相反态度，二是对因大众文化的多元性和矛盾性而带来的难题还没有找到很好的解决办法。     

基于RL&SM通用夹具系统的主动寻位技术及其实现方法

介绍了RL&SM通用夹具的寻位系统 ,描述了主动寻位与制造信息转换问题 ,提出和实现了相应的控制方法及其系统实现中的关键技术。理论分析与实验结果表明 ,提出的解决方法和技术是可行的 ,为RL&SM通用夹具系统的实际应用奠定了理论基础和技术支持     

A FUNDAMENTAL SOLUTION FOR THE LAPLACE OPERATOR ON THE QUATERNIONIC HEISENBERG GROUP

In this paper, the author studies the Laplace operator on the quaternionic Heisenberg group, construct a fundamental solution for it and use this solution to prove the Lp-boundedness and the weak (1-1) boundedness of certain singular convolution operators on the quaternionic Heisenberg group.     

系数变号的半线性椭圆方程的正解

本文研究半线性椭圆方程Dirichlet问题-△u=α（x）f(u），x∈Ω， u（x）=0，x∈ЭΩ，正解的存在性，其中Ω为R^n中有界的带光滑边界的区域，α(x)可以变号。     

Proton conductivity of phosphoric acid derivative of fullerene

The proton conductive property of methano [60] fullerene diphosphoric acid has been investigated under various humidity conditions at the temperature range between 15 and 45 °C. It shows proton conductivity as high as 10⁻² S cm⁻¹ at 25 °C under relative humidity of 95%. Thermal analyses including TG–DTA and thermal desorption mass spectroscopy (TDS) confirm that the compound is thermally stable up to 200 °C. Proton conduction of the compound depends very much on humidity or water content. The logarithmic conductivity at 25 °C is increased linearly with increasing relative humidity. The activation energy (E_a) estimated from the slope of log(σT) vs. 1/T is decreased from 1.08 to 0.52 eV, as the relative humidity is increased from 40% to 75%. The humidity dependence of conductivity is discussed in the light of the observed hydration isotherm.     

PVK∶DBVP掺杂体系的能量转移及发光性质的研究

研究了不同比例的PVK与齐聚PPV衍生物DBVP掺杂体系的能量转移和发光特性.通过对PVK,DBVP及PVK:DBVP掺杂体系的UV-vis,PL和PLE光谱的研究,分析了PVK与DBVP之间的能量转移过程.利用PVK在体系中类似于溶剂的分散作用,制备了结构为ITO/PEDOT/PVK:DBVP/LiF/Al的电致发光器件,研究了掺杂体系的电致发光性能.结果表明,在掺杂体系的光致发光和电致发光中,PVK的发射被有效地抑制,PVK与DBVP之间发生了非常有效的能量转移,通过调节PVK与DBVP的比例,可以获得蓝色和绿色发光,同时可以改善器件的发光性能,当PVK与DBVP的重量比为1∶2时,器件的绿色发光效率达到1·06cd/A,此时发光亮度为52cd/m2.     

用增量有限元法计算金属流动

利用增量有限元理论 ,对金属材料的变形过程进行模拟。为了模拟工程中塑性变形较大的构件的变形规律 ,在每个加载步迭代完成后自动实现坐标更新。