A method for determining optical constants, dimensions, and concentrations of “soft” absorbing particles in the brightening band region

We investigate the possibilities of creating a method for estimating the optical constants, dimensions, and concentrations of “soft” absorbing particles by applying a theoretical analysis of the angular dependence of the intergrated indicatrix, overall characteristics of light scattering, and absorption on the phase shift and diffraction parameter of particles in the brightening band region. We show that using the investigated optical characteristics, it is possible to determine the unknown parameters of a suspension from experimental data. Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 6, pp. 807–812, November–December, 1997.     

A Pseudo-Random Frequency Modulation Continuous Wave Coherent Lidar Using an Optical Field Correlation Detection Method

We propose a new detection method for a pseudo-random frequency modulation continuous wave (RM-CW) coherent lidar. The feature of this method is modulation of local beam with a time delayed pseudo-random sequence. Heterodyne detection and correlation detection between the received beam and the local beam are simultaneously carried out in an optical field. In the RM-CW coherent lidar using the optical field correlation detection method, the received equipment is greatly simplified. We carried out preliminary experiments and demonstrated that the new method is effective for detection of a CW coherent lidar.     

Alternating copolyfluorenevinyles with polynuclear aromatic moieties: Synthesis,photophysics, and electroluminescence

Three new copolymers, namely poly(fluorenevinylene‐alt‐naphthalenevinylene) ( N ), poly(fluorenevinylene‐alt‐anthracenevinylene) ( A ) and poly(fluorenevinylene‐alt‐pyrenevinylene) ( P ), were synthesized by Heck coupling of 9,9‐dihexyl‐2, 7‐divinylfluorene with a polynuclear aromatic dibromide. The 9,10‐disubstituted anthracene was obtained exclusively for A while N and P were obtained as a mixture of two isomers with predominant the 1,4‐disubstituted naphthalene and 1,8‐disubstituted pyrene, respectively. The polymers were soluble in common organic solvents and decomposed above 370 °C. Their glass transition temperature increased from 58 to 110 °C by increasing the number of the phenyl rings of the polynuclear aromatic moiety. Rather high‐efficiency blue and blue‐greenish photoluminescence (PL) of these copolymers in solution was largely decreased in their films, indicating the presence of concentration quenching in the solid state. The OLED using these polymers demonstrated green EL in the case of copolymers N and A , and red EL in the P derivative with η_EL = 0.26–0.31%. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4661–4670, 2007     

一种新型有机电致微腔结构的双模发射

采用结构Glass／DBR／ITO／NPB／NPB：Alq／Alq／Al制作了有机微腔电致发光器件。将空穴传输材料与发光材料以一定比例混合作为发光层，为了便于对比，在不改变有机层的膜厚的情况下同时制作了传统的异质结微腔器件，发现两种器件的发光光谱有很大不同，器件的复合效率与传统的异质结器件相比也得到了很大提高，这是因为将两种有机材料混合能消除界面势垒，提高器件的复合效率，从而提高了器件的发光性能，实现了微腔双模发射，且两个模式的半峰全宽分别为8nm和12nm。通过进一步优化器件结构可以实现微腔白光发射。     

玻色—爱因斯坦凝聚和兰姆位移

扼要地介绍了ＢＥＣ研究的近况和研究方向，同时报道了我们在ＢＥＣ的光散射和兰姆位移方面的研究工作     

D→Klv～l衰变过程的研究

用光锥QCD求和规则研究D→Klv～_l衰变过程，首先计算D→K跃迁形状因子，通过构造新的关联函数，消除了twist-3波函数的不确定性给计算结果所带来的影响，从而使计算结果更加精确. 计算得到的分支比与最近的实验数据相一致. 关键词： QCD光锥求和规则 D介子半轻衰变 分支比 形状因子     

杨氏双缝干涉实验中的光谱奇异现象

基于部分相干光的传输理论,研究了杨氏双缝干涉实验中的光谱奇异现象。发现在杨氏双缝干涉实验干涉场区中的某个点的光谱奇异现象,它会随着某些参量(如源光谱宽度Γ′,缝宽参量ε,相对空间相干度Δ0)的变化而改变,指出该现象可应用于信息的编码及自由空间的信息传输。     

荧光光纤温度传感器激励光源的选择

本文分析计算了荧光光纤温度传感器的温敏元件——GsAlAs/GaAs双异质结半导体材料的荧光辐射效率与激励光波长的关系。讨论了温度测量范围及温敏元件GaAlAs层铝含量对激励光源的限制,在0～200℃测温范围内,若采用LED作激励光源,其峰值波长应在0.70～0.76μm之间选择。