阴影像与眼像差仪的几何光学原理

Howland像差仪是一种由正负柱透镜中间夹着格栅组成的系统。它通过检出人眼透过像差仪所视的变形格栅图中的偏移变形量,来获得对应的人眼的波像差信息。建立了该系统的等效光学成像模型,从格栅所成阴影像的概念出发,得到其成像公式,给出人眼波像差计算方法。     

一种新的消色像全息术

本文从全息再现像的物像关系出发,对准像面情况下,像点随波长及参考光源扩展的变化进行了研究.阐明了利用散射线光源作参考光使全可见光范围内的像叠加在一起,产生消色像全息图的基本思想,并引入了消色像域的概念.考虑到点基元全息图尺寸及人眼瞳孔对成像光束的限制,白光再现时,可以获得清晰、明亮、具有一定景深和相当视场范围的消色再现像.     

用MeF3金相显微镜研究LiNbO3晶体的光像

用MeF_3金相显微镜观察了多畴和单畴的LiNbO_3晶体的X、Y、Z切面的蚀像和光像.发现各切面光像形态与各切面的蚀像形态对应,并与晶体的对称性完全一致.利用晶体的光像确定晶体极性和晶轴是一种简便的光学方法.     

光纤传像束的物镜设计

分析3种像方远心系统的结构和用途。在传像光纤物镜的设计过程中,分别采用传统单组像方远心系统和“负-正”型式的像方远心光学系统结构,通过比较发现“负-正”型式的像方远心系统的结构能很好地解决镜头轴外像差校正和像面照度均匀性的问题,并且镜头结构紧凑。使用ZEMAX光学软件进行优化,给出工作波长(0.38～0.78)μm,焦距1.92mm,视场角60°,相对孔径为1∶4的镜头设计实例。设计结果表明:此镜头在46lp/mm处的MTF大于0.8,像质优良。     

电子稳像技术及其发展

简单介绍了电子稳像技术的基本概念及产生、发展过程 ,重点分析了几种典型的电子稳像系统 ,在此基础上给出了其原理工作框图 ,并详细阐述了电子稳像技术的实质及其目前发展方向     

四方晶系SBN晶体中位错光双折射像的理论计算和实验观察

本文计算了铌酸锶钡(SBN)晶体中沿光轴的位错双折射像的反衬,计算中考虑了光弹系数的各向异性,结果表明与各向同性计算相比刃位错双折射像中的花瓣有伸长的趋势,螺位错无反衬,并与实验结果作了比较。     

偏心光学系统的中心点亮度的计算

本文讨论了偏心光学系统的中心点亮度计算中所必须考虑的离焦、波差展开式、数值计算等几个主要问题。     

电子稳像技术中的坐标变换及像偏移函数分析

为了进行图像偏移的数字补偿 ,需要分析图像的偏移函数 ,要对定坐标系O0 X0 Y0 Z0 ,CCD摄像机载体坐标系O1X1Y1Z1和像空间坐标系O2 X2 Y2 Z2 进行坐标变换 ,从而得出图像偏移与载体运动速度的关系 ,为数字电子稳像奠定基础。     

变焦距镜头最佳像面位移的调整

通过移动变倍组和补偿组，在保证所要求的变焦倍率的同时，考虑高级像差对最佳像面的影响，调整各组之间的间隔，使之尽量符合各焦距最佳像面的位移变化，最终达到在各种焦距位置时对高斯像面的严格一致。     

颤振对TDICCD相机像质的影响分析

为了分析卫星颤振对TDICCD相机像质的影响,给出了低频正弦颤振引起的相机像移,重点分析了滚动、俯仰、偏航三个方向的颤振对相机成像质量的影响.通过对两种卫星颤振动力学仿真数据的计算,具体研究了颤振对相机像质的影响程度.结果表明,TDICCD相机对卫星颤振幅值要求较高,且随TDI积分级数的增加,颤振的影响尤为突出,必须加以限制.     

煤颗粒热膨胀量与破碎特性的研究

煤颗粒的热膨胀破碎特性直接影响流化床锅炉的运行效率.本文利用热机械分析仪(TMA)测定了不同种类不同密度的型煤和原煤的热膨胀特性,并对部分破碎微观形貌进行了FSEM观察;通过旋转炉内的燃烧试验研究了热膨胀特性和破碎的关系.研究表明,煤颗粒在燃烧过程中其热膨胀破碎主要发生在挥发分析出阶段;内部挥发分的析出会使颗粒内压增大而产生膨胀,进而产生细小裂纹并破碎;挥发分越高,颗粒密度越大,其热膨胀形变率越大,越容易发生破碎现象;主要挥发分析出后热膨胀引起的破碎可以忽略.     

CCD摄像系统镜头的畸变测量

从畸变定义出发,讨论了畸变数学模型,介绍了精密测角法与比长法综合测量畸变的原理。通过放大率法标定出CCD探测器的像素距离当量,通过质心法求出点目标的质心,质心与原点的像素距离乘以像素距离当量得到精确长度。利用正切函数求出绝对畸变值,用最小二乘法解多组数据超定方程,求出拟和公式的系数。实际计算和数据处理结果表明：畸变数学模型在中视场范围内拟合效果很好。     

旋涡的场特征与物质性──离散涡方法基础

旋涡的场特征与物质性──离散涡方法基础吴文权（华东工业大学，上海，２０００９３）关键词旋涡动力学，旋涡场性，旋涡物质性众人关注的不稳定、非定常、分离流动无不与旋涡有关。因而对旋涡的研究吸引了人们的注意。尤其是近来非线性科学的发展，提供了新的思想、方法...     

发射光谱法测定乳浊料中的锆和铪

研究了用碳粉和二氧化钛作缓冲剂同时测定乳浊料中的锆和铪的发射光谱法,选择钛作内标线,不需分离、不需化学处理,直接压样于杯形的石墨电极中,具有简便、快速、准确的特点。对测定条件、干扰因素进行了研究,从而建立测定锆和铪的新方法。锆和铪的分析线分别为327.3和286.6 nm,内标线选择为钛的308.8 nm线,锆和铪的线性范围分别为0～0.50%和0～0.25%。锆和铪的检测限分别为0.001%和0.010%,其回收率为96.67%～105.0%,当n=9时,锆的RSD为3.61%;铪的RSD为4.82%;用于样品的测定取得了满意的结果。     

Design and development of a fiber-optic immunosensor utilizing near-infrared fluorophores

The design and application of a fluorescent fiber-optic immunosensor (FFOI) are reported. The FFOI is utilized for the detection of antibody/antigen binding within the near-infrared (NIR) spectral region. The technique is developed through the combined use of fiber-optic, semiconductor laser-excitation, fluorescence detection, NIR dye, and immunochemical techniques. The antibody is immobilized on the FFOI and utilized as a recognition component for trace amounts of specific antigen. The FFOI is constructed to utilize an antibody sandwich technique. The assay involves the immobilization of the capture antibody on the sensing tip of the FFOI followed by the exposure of the immobilized sensing tip to the antigen. The antigen-coated FFOI is then introduced to a second antibody previously labeled with the NIR dye. Typical measurements are performed in about 15 min. A semiconductor laser provides the excitation (780 nm) of the immune complex. The resulting emission is detected by a silicon photodiode detector (820 nm). The intensity of the resulting fluorescence is directly proportional to the concentration of the antigen. The sensitivity of the analysis reaches 10 ng/ml and the response time is 10–15 min.     

Structure prediction and aromaticity of acenes and phenylenes series. A combination method between asymmetric Kekulé structures

The combination method between asymmetric Kekulé structures (CMAK) was expanded to the structure prediction of a series of acenes and phenylenes. The structures predicted by the CMAK correspond to those calculated by the ab initio molecular orbital (MO) and B3LYP density functional methods. The CMAK can characterize the structures. The aromaticity for the whole ring and each ring in the treated compounds was estimated by the index of deviation from aromaticity (IDA). The estimated aromaticity corresponds fairly well to the characterization of the structure predicted by the CMAK. The predicted structures of linear acenes reveal the aromaticity of the central ring and also explain its reactivity. The side ring in [n]phenacene shows high aromaticity. The critical difference in the structure and aromaticity for the central six‐membered ring of the isomers benzo[1,2:4,5]dicyclobutene and benzo[1,2:5,6]dicyclobutene was explained. Copyright © 2012 John Wiley & Sons, Ltd.     

Characterization of cold-sprayed nanostructured Fe-based alloy

The ball-milled Fe-Si alloy was used as feedstock for deposition of nanocrystalline Fe-Si by cold spraying process. The microstructure of the as-sprayed nanostructured Fe-Si was characterized by using optical microscopy, scanning electron microscopy and transmission electron microscopy. The grain sizes of the feedstock and as-sprayed deposit were estimated based on X-ray diffraction analysis. The microhardness and coercivity of the deposited Fe-Si alloy were characterized. The results showed that the as-sprayed deposit presented a dense microstructure. The mean grain size of the as-deposited Fe-Si was several tens nanometers and comparable to that of the corresponding milled feedstock. The temperature of driving gas presented little effect on the microstructure of cold-sprayed nanostructured Fe-Si deposit. The mechanical alloying induced oxygen contents up to 8 wt% in the feedstocks and subsequent deposits. The microhardness of the deposit reached about 400 Hv. The deposit achieved a high coercivity up to 190 kA/m indicating the potential possibility for applications to recording materials.     

高功率宽谱开关振荡器

采用1/4波长开关同轴谐振器技术路线,开展了高功率宽谱微波产生及耦合输出技术研究。设计振荡器工作在200 MHz,低阻抗1/4波长同轴传输线与传输线一端的环形多通道气体火花开关构成谐振器,耦合器由集中电容和分布电感构成,实现宽谱微波的能量提取。通过数值模拟研究了振荡器的振荡及耦合输出过程,分析了高压脉冲馈入方式、谐振器阻抗特性及开关齿槽结构对环形开关导通特性的影响。数值模拟和实验结果证明,采用直馈方式、高阻结构和齿槽结构有利于形成开关多通道导通,并提高开关导通的稳定性。在输出电压为500 kV的Marx脉冲功率源平台上构建了高功率宽谱微波产生实验装置,实验得到的宽谱微波振荡频率为195 MHz,辐射因子约150 kV,频谱带宽约30%。     

Effect of Fe-doping on the structural,morphological and optical properties of ZnO nanoparticles synthesized by solution combustion process

The effect of Fe-doping on the structural, morphological and optical properties of ZnO nanoparticles synthesized by simple solution combustion process are reported. The powder XRD pattern indicates that the Fe-doped ZnO samples exhibit primary and secondary phases. The primary phase indicates the hexagonal wurtzite structure with the average crystalline size of around 25–50 nm and the secondary phase is associated with the face centered cubic structure of magnetite iron oxide. The elemental composition of pure and Fe-doped samples are evaluvated by EDX. The results of FE-SEM and HR-TEM cleary show that particles morphology have changed with respect to the incorporation of doping agent and particles are in aggregating nature. The vibrational properties of the synthesized ZnO nanoparticles are investigated by Raman scattering technique and it exhibits that the influence of Fe-doping significantly modify the lattice vibrational characteristics in ZnO sites. The optical properties of the Fe-doped ZnO nanoparticles are carried out by UV–vis absorption and PL spectra. The results of PL spectra show the near-band edge related emission as well as strong blue emissions in the Fe-doped ZnO nanoparticles.     

基于线偏振光反射率测量介质折射率的研究

研究线偏振光的振幅反射率与介质折射率的关系,提出一种测量介质材料折射率的方法。文中从菲涅耳公式出发,推导出各向同性介质的线偏振光反射率与折射率的关系式,给出基于线偏振光反射率测定介质折射率的原理。设计实验方案,在不同入射角情况,定出线偏振光p方向和s方向两种线偏振光在玻璃表面的反射率,得到线偏振光振幅反射率随入射角变化的实验曲线。依此实验数据得出材料的折射率。结果表明,测出的介质材料的折射率与理论值相符,所采取的测定方案可行。