烷基链长对四苯基乙烯衍生物聚集行为和光学性质的影响

制备了带有不同烷基链长的四苯基乙烯衍生物1,1,2,2-四(4-正己氧基苯基)乙烯(THPE)和1,1,2,2-四(4-正癸氧基苯基)乙烯(TDPE),并采用紫外吸收光谱、荧光光谱研究THPE和TDPE在四氢呋喃(THF)/H_2O混合溶剂中的光物理性质,通过扫描电镜观察THPE和TDPE在THF/H_2O中形成的聚集体的形态结构。结果表明,THPE和TDPE在THF/H_2O中的紫外吸收光谱都出现拖尾现象,然而开始出现拖尾时溶剂中的水含量不同,THPE和TDPE分别在水含量为50%和40%的THF/H_2O中开始出现拖尾现象;THPE和TDPE都具有聚集诱导发光(AIE)性能,它们的荧光量子产率随着水含量的增加而增大,但是荧光量子产率快速增长的起始点不同,THPE和TDPE的荧光量子产率分别在水含量达到40%和30%后开始快速增长;THPE和TDPE在THF/H_2O中都能形成形状规则的聚集体,不同的是THPE在水含量为70%时才形成有序的纳米棒,而TDPE则在水含量为50%时即能形成纳米棒和微米片。这表明,带有长烷基链的TDPE更容易聚集,通过调节烷基链长度,有望制备出发光效率高、聚集体结构可控的AIE材料。     

咪唑基改性的水溶性PDI荧光材料的合成和表征及对Cu2+离子的荧光检测

以3,4,9,10-苝四甲酸二酐为原料合成了水溶性荧光材料-N,N'-二(1-氨丙基-3-丙基咪唑盐)-3,4,9,10-苝四羧酸二酰亚胺(PDI),引入的咪唑基团使PDI不仅溶于DMSO、DMF等有机溶剂,可溶于EtOH/H2O、Acetone/H2O、THF/H2O等的混合溶液,不仅提高了PDI在有机相和有机相/水相的溶解性,同时扩展了PDI的适用范围.对比不同的混合溶剂发现,PDI在EtOH/H2O中的荧光较强,UV-Vis最大吸收波长和荧光最大发射波长分别为526nm和540nm.进而在EtOH/H2O溶剂中,比较了PDI对各种离子的荧光识别作用,其中PDI作为Cu2+的荧光探针时,受干扰小,选择性较高.TG结果表明,PDI拥有高的热稳定性,温度达353℃时质量损失仅为5％.     

新型POSS基有机/无机杂化分子发光材料的制备及聚集效应研究

有机发光材料在电致发光与显示器件领域有着非常广泛的应用。以具有高荧光量子产率的长共轭芴类衍生物2-乙炔基-7-(4-(4-甲氧基苯乙烯基)苯乙烯基)-9,9-二辛基芴(EMOF)和POSS(T8H8)为原料,通过硅氢化反应制备了POSS基有机/无机杂化分子发光材料(EMOF-POSS),并用FT-IR、1H-NMR和13C-NMR对其结构进行了表征。通过紫外-可见和荧光光谱研究了EMOF和EMOF-POSS在不同比例的THF/H2O混合溶剂中的聚集效应,并对两者的热性能进行了测试。结果表明,EMOF-POSS不仅具有较好的热稳定性,而且有效地降低了荧光生色团的聚集,从而提高了材料的荧光量子产率(ΦFL)和发光性能。     

自由基聚合制备聚集诱导发光聚合物

首先制备了基于四苯基乙烯的聚集诱导发光(AIE)单体1-(4-丁烯氧基苯基)-1,2,2-三苯基乙烯(TPEBE)。然后,通过自由基溶液聚合法,将少量TPE-BE与丙烯酰胺和丙烯酸共聚制备了亲水性聚合物P1,与苯乙烯共聚制备了疏水性聚合物P2。利用红外光谱表征了P1和P2的结构,通过荧光光谱研究了P1和P2的发光性能,并探讨了聚合物亲疏水性对其发光行为的影响;采用扫描电子显微镜(SEM)观察了P2在四氢呋喃(THF)/H_2O混合溶剂中的微观形态。结果表明:P1在水中发出蓝光,随着THF的加入,荧光逐渐减弱,然而,P2在THF及THF/H_2O混合物中都不发光,表明聚合物的亲疏水性能够影响其发光行为。然而,P1和P2的固态粉末都发出较强的荧光,说明P1和P2具有聚集诱导发光性能。P2在水质量含量超过30%的THF/H_2O混合溶剂中能够形成微球。这表明通过调整共聚单体的种类,有望制备出结构和功能多样的AIE聚合物。     

苝酰亚胺类化合物的功能改性及光谱性能研究

本文合成了三种含有羧基的苝酰亚胺化合物，并研究了其紫外-可见吸收光谱及荧光光谱的特征；研究表明，苝环上1，6，7，12位取代基的引入，使得所合成的苝酰亚胺类化合物的最大吸收波长分别红移了50nm、49nm；Stokes位移变大30、31nm。而荧光量子产率的下降，但不是很明显。     

具有聚集诱导发光特性含萘单元共轭聚合物的合成

首先氯化亚砜和2,6-萘二甲酸酰氯化反应合成2,6-萘二甲酰氯(M1),然后M1和叔丁基苯傅-克酰基化反应合成2,6-二(4-叔丁基苯甲酰基)萘(M2),进而与1,2-乙二硫醇合成2,6-双(2-(4-(叔丁基)苯基)-1,3-二巯基-2-基)萘(M3),最后以六羰基钨为催化剂,分子间脱硫反应制备含萘单元共轭聚合物PNTB。利用傅里叶变换红外光谱仪、核磁共振波谱仪、凝胶渗透色谱仪、紫外-可见分光光度计和荧光分光光度计对M2、M3和PNTB的化学结构、相对分子质量和光学性质进行测试与表征。结果表明,随四氢呋喃/水(THF/H_2O)混合溶剂中水分数不断增加,PNTB的荧光强度呈递增的趋势,表明PNTB具有聚集诱导发光特性。PNTB在溶液状态(THF为溶剂)和聚集状态(THF/H_2O,体积比10/90)的荧光量子产率分别为1.83%和12.74%,说明PNTB容易发生聚集,聚集诱导发光效果良好。     

以苝酰亚胺为构筑单元的π-π堆积型超分子聚集体的研究进展

苝酰亚胺作为一类独特的n-型有机半导体材料,以其为构筑单元形成的超分子聚集体具有独特的光物理和光化学性质,在光电功能器件上具有广阔的应用前景。综述了近年来以苝酰亚胺为构筑单元,π-π堆积引导构筑的各种超分子聚集体的研究现状,这些超分子聚集体展现出丰富的形貌结构和独特的光电功能。简单介绍了苝酰亚胺自组装纳米材料在场效应晶体管和气体传感器方面的应用。最后,对其发展前景作了展望。     

苝酰亚胺衍生物的合成及其荧光性能研究

以3,4∶9,10-苝四羧酸二酐为原料,合成了N,N′-二(1-戊基己基)-1,7-二对叔丁基苯氧基-3,4∶9,10-苝四羧酸二酰亚胺,使用1 H-NMR、MS、紫外-可见吸收光谱、荧光光谱对所合成的化合物进行了表征,并研究了其对常见有机小分子的荧光传感性能,发现对苯胺具有较好的选择性。     

两种有机化合物DMAHAS和DMANHAS的合成、表征和非线性光学性质

合成了两个有机化合物：反式-4-(N-羟乙基-N-乙基胺基)-4′(二甲基胺基)二苯乙烯(简称DMAHAS)和反式-4-[N-(乙基4″-硝基苯甲酰基)-N-乙基胺基]-4′-(二甲基胺基)二苯乙烯(简称DMANHAS)。用核磁、红外光谱以及元素分析进行了表征。测试了紫外吸收光谱、单光子荧光光谱和双光子荧光光谱。在800nm的飞秒脉冲激光的激发下，DMAHAS发出较强的蓝紫色上转换荧光。荧光峰位于430nm。而在相同条件下DMANHAS的荧光淬灭。     

苝纳米片的制备和光学特性

利用再沉淀法将Perylene/THF溶液注入甲醇和水的混合溶剂中制备了苝纳米薄片,采用扫描电镜（SEM）、吸收光谱对纳米片形貌和光学特性进行了表征,结果表明,注入不同体积Perylene/THF溶液的苝纳米片表现出不同光学特性,同时对纳米片的形成机制进行了初步的分析和探讨。     

Estimation of Parameters of Universal Distribution of Moments of Failure of Products

A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling.     

Evaluation of optical properties of highly scattering media by moments of distributions of times of flight of photons

A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue.     

Analysis of the rate of propagation of the wave of change of boiling modes

An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate agreement is demonstrated between the derived relations and experimental data.     

Estimation of potentialities of methods of summation of direct measurement errors

Conventional methods for summation of direct measurement errors are considered. Conditions under which these methods provide consistent results are stated. It is proposed to utilize for characteristic of the total error, its interval estimator or the half-sum of the value obtained by adding up its arithmetic and geometric random errors.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 10–12, April, 1995.     

空压机轴承箱蜗壳温度探头油封改造

由于空压机进气侧轴承箱蜗壳温度探头密封效果不好,使空压机及其后续管道受到油污染。后将温度探头的O形圈密封改为骨架油封,杜绝了轴承箱漏油问题。文章简介空压机的结构和技术参数,详细介绍了骨架油封的制作和优点。     

Characteristics of mechanical properties of materials in studies of conditions of attainment of marginal states

It is shown that conditions of attainment of marginal states in the material of structural components are formulated on the basis of analysis of force and deformation criteria of formation and development of destruction. The parameters of these criteria are data on types of structural materials, standard and special characteristics of their mechanical properties, structural forms of considered elements of the equipment, and their operating stress loading. In this case, the construction of a system of state equations for describing interrelation of current damage, external actions, and responses to them is based on the concept of calculating variations in properties of materials at all stages of the design life cycle.     

Determination of parameters of microstructural inhomogeneity of deformation of metals by the method of modeling

The article suggests a method of evaluating the microstructural inhomogeneity of deformation of metals by modeling. The method includes the measurement of deformations of metal according to meshes of a dividing grid with small base and the calculation of the distribution parameters of microdeformations in model representation. It is shown that the modeling method makes it possible objectively to evaluate the microinhomogeneity of deformation of metals independently of the chosen mesh size of the dividing grid. New structural characteristics are introduced: the base and wave of variation expressing the degree of crumbling or amalgamation of metal grains by inhomogeneity of deformation.Translated from Problemy Prochnosti, No. 7, pp. 40–44, July, 1991.     

水三相点复现的不确定度评定

水三相点是开尔文热力学温度的唯一基准点，也是ITS-90国际温标重要的定义固定点。因此，水三相点不确定度分析对整个温标的建立、温度量值传递起着至关重要的作用。近3年来，中国计量科学研究院研制出一系列高质量的水三相点容器，加强了水三相点的研究，为不确定度的分析提供了更为可靠的实验依据。同时，不确定度的分析也是客观评价新研制容器性能的一个重要指标。因此，根据实验结果对新研制容器所复现的水三相点进行了不确定度评定。评定结果表明，其扩展不确定度为0．16mK(k=2．69，P=0．99)。