己氧基对含二苯乙烯基发色团化合物荧光性能的影响

合成了两种新型甲基丙烯酸酯类化合物：4-甲基丙烯酰氧基-4’-硝基二苯乙烯(NS)和4-甲基丙烯酰氧己氧基-4’-硝基二苯乙烯(HNS),通过红外光谱、核磁、高效液相色谱、紫外吸收光谱等对化合物结构进行了表征。研究了两化合物的荧光发射光谱,考察了浓度、溶剂极性等对化合物荧光发射光谱的影响。结果表明,化合物NS、HNS均存在浓度自猝灭效应,其荧光最大发射波长均随着溶剂极性增大而红移;且HNS由于供电子己氧基的引入在分子内形成了推-拉电子结构,使得其荧光最大发射波长较NS红移了72nm,化合物在DMF溶液中产生的荧光由黄光转变为橙红色光。     

脱氢枞酸基D-A型分子的合成、空间构型及光谱性能

对三苯胺进行溴代和C-N偶联反应合成4-萘基三苯胺(a),对脱氢枞酸进行酯化、溴代、硝化、还原和C-N偶联反应合成13-[N,N-(4-萘基苯基)-苯基]胺基-脱异丙基脱氢枞酸甲酯(b)及13-[N,N-双(4-萘基苯基)]胺基-脱异丙基脱氢枞酸甲酯(c)两个化合物,通过1H MNR,13C MNR及MS对化合物的结构进行表征。为了研究化合物结构与光谱性能之间的关系,首先利用Gaussian 09程序采用密度泛函DFT/B3LYP方法,对三个化合物的空间构型进行全优化,得到它们的键长、键角和二面角,对比发现脱氢枞酸骨架和萘环的引入会影响化合物的共平面性,而萘环的引入会增大化合物的共轭程度。光谱性能方面,研究了三种化合物在甲醇、二氧六环、四氢呋喃、二氯甲烷和环己烷这5种极性逐渐减小的溶剂中的荧光发射光谱和紫外吸收光谱。结果表明,在荧光光谱中,化合物a,b和c在不同极性溶剂中最大荧光发射波长均有不同程度位移,在甲醇中最大,在环己烷中最小,但是位移并非随着极性的增大而只发生红移,在二氯甲烷、四氢呋喃和二氧六环3种极性依次增大的溶剂中,a,b,c的荧光发射波长均随着溶剂极性的增大而发生较大程度的蓝移;在同一溶剂中,化合物b和c相对于a的荧光发射波长依次发生红移,c的红移程度与b差距不大。紫外吸收光谱中,三个化合物在不同极性溶剂中的最大吸收波长也有差异,在200～250 nm区间,三个化合物均在二氯甲烷中有较大位移,在300～350 nm区间,在甲醇中位移较大,而在250～300 nm区间,最大吸收波长差别不大;在同一溶剂中,它们在300～350 nm区间的最大吸收波长差别较大,化合物c较a红移26 nm。结合结构优化所得数据可以证明,化合物的共轭程度对荧光发射光谱和紫外吸收光谱均有影响,而共平面性对荧光发射光谱影响较大。化合物a,b和c在不同极性溶剂中荧光发射光谱和紫外吸收光谱的较大变化,表明它们有明显的溶致变色行为,具有作为分子探针探测外部环境极性大小的潜能。     

新型吡唑啉类荧光化合物的合成及光谱分析

吡唑啉衍生物作为荧光增白剂具有优良的性质,已被广泛应用于染料工业。根据Schellhammer化学结构与荧光性的经验,在吡唑啉环的1-位引入苯并噻唑基,3-位引入吲哚基,5-位引入苯基衍生物,设计并合成了六种新的吡唑啉衍生物,并且通过红外光谱、1H NMR谱、质谱和元素分析进行了确证。化合物的荧光性能测定结果显示此类化合物具有良好的荧光性,均可吸收353 nm左右紫外光,最大发射波长在430～443 nm之间,是一类很有发展前途的蓝紫色荧光化合物。荧光最大发射波长和荧光强度与取代基有关,在苯并噻唑上引入6-Br基团,化合物的荧光发射波长发生蓝移,且强度增大;而引入CH₃基团,化合物的荧光发射波长发生红移,且强度降低。取代基和溶剂极性对荧光量子产率的影响较小。荧光相对强度与荧光量子产率没有直接关系。     

α-和β-四烷氧取代酞菁的合成及性能研究

利用 3 烷氧取代邻苯二腈和 4 烷氧取代邻苯二腈与相应的金属盐反应制备了两大系列 (α 和 β )四烷氧取代酞菁 .讨论了温度对中间体烷氧取代邻苯二腈合成的影响 ,探讨了酞菁的两种环合方法 ,并对 β 烷氧酞菁的环合历程进行了初步的考察 .研究了不同取代位置和酞菁的最大吸收波长之间的关系 ,结果表明 ,α 取代烷氧取代酞菁导致λmax红移值较大 ,而相应 β位取代情况下红移值较小 ,说明给电子基团在α位对酞菁骨架的π共轭结构微扰作用比 β位大 .同时研究了溶解度及热失重与酞菁结构的关系     

高相对分子质量8-羟基喹啉锂聚合物的制备和性能

高分子电致发光显示器(PLED)是近几年来国际、国内的研究热点,取得了很大的进展,其中高分子化金属配合物是一类很有价值的功能材料。通过甲基丙烯酸甲酯(MMA)、苯乙烯(S)和含有8-羟基喹啉的单体共聚合成模板聚合物,再与氢氧化锂作用,实现了8-羟基喹啉锂配合物的高分子化,获得了一种能够溶解在普通的溶剂中的高相对分子质量的含喹啉锂配合物的发光聚合物,并利用元素分析、¹H-NMR、FTIR、UV、PL光谱、DSC、TGA、GPC等方法对其结构和性能作了表征。紫外吸收和光致发光(PL)光谱说明合成共聚物的发光来自于Liq基团,引入的可聚合的链段以及共聚物中的甲基丙烯酸甲酯或苯乙烯链段,并没有影响发光波长的改变。亲核溶剂改变8-羟基喹啉金属配合物分子结构,使共聚物光谱明显红移20nm左右。     

偶氮金属螯合物薄膜的光学常数和吸收光谱

偶氮金属螯合物薄膜是一类新型光信息存储和光学非线性材料。通过旋涂法在单晶硅上制备了三种新型偶氮染料：2-（4-甲革-2-噻唑基偶氮）-5-二乙基胺苯酚（MTADP）掺杂聚合物,MTADP的镍螯合物（Ni-MTADP）和锌螯合物（Zn-MTADP）薄膜。利用宽谱扫描全自动椭圆偏振光谱仪测定了上述薄膜的椭偏光谱,获得了三种薄膜在400—700nm波段的复折射率、复介电常量和吸收系数。两种金属螯合物薄膜的共振波长比非螯合物薄膜红移了60—70nm;光学常数和吸收系数在峰值的数值也发生了明显的变化。由于这两种螯合物具有不同的立体结构,Ni-MTADP薄膜的共振波长比Zn-MTADP有10nm的红移。     

含炔基有机硅共轭聚合物的光谱性能研究

应用荧光光谱、紫外光谱对不同结构的含炔基有机硅共轭聚合物的发光性能进行了表征和研究。探讨了聚合物主链上Si原子取代基的结构以及主链中炔基单元结构对其发光性能的影响,研究结果表明,聚合物可在219～260 nm处有紫外吸收,随着Si原子上取代基共轭性能的增强,以及主链中炔基数目的增多、链段共轭程度的增大,最大吸收波长红移。取代基的影响较小,主链共轭结构对吸收光谱的影响明显。不同主链结构的共轭聚合物在320～353 nm处发出一定强度的荧光。结果显示,聚合物主链共轭基团的结构对发射光谱具有明显的影响,随着主链中炔基数目的增多,最大发射波长显著向长波方向移动。由于此类聚合物的特殊结构使得他们具有良好的热学稳定性,因此这类聚合物具有潜在的光学应用价值。     

微波合成N-6-喹啉基-α-苯丙氨酸及其紫外光谱

以对溴苯胺和2-烯丙醛为原料,通过Skraup环化反应合成6-溴喹啉,进而与α-苯丙氨酸作用,采用不同方法合成了N-6-喹啉基-α-苯丙氨酸.探讨了微波辐射时间、辐射功率及缚酸剂种类等对合成产率的影响,最佳条件下产率可达94.5％.目标化合物的结构通过1H NMR、IR、元素分析和紫外光谱等方法进行了表征,紫外光谱研究表明:目标化合物的吸收波长红移,强度增加.     

pH敏感功能聚合物的研究

以荧光染料曙红为pH指示剂、甲基丙烯酸为单体、双甲基丙烯酸一缩二乙二醇酯为交联剂、庚烷为致孔剂,利用高分子聚合技术合成了pH敏感功能聚合物。考察制备pH敏感功能聚合物的影响因素条件及其pH响应行为。曙红染料在聚合物介质中由于极性的减弱,其最大荧光发射波长较在水溶液中红移,表观解离常数增大,对pH的响应区间向酸性方向移动。在最佳实验条件下,pH敏感功能聚合物对pH的响应范围为0～3.0,并且具有较好的可逆性和重现性。     

具有电子推拉结构的多支化分子的光物理特性的研究

利用稳态光谱和飞秒时间分辨荧光亏蚀的技术,研究了不同溶剂中一系列有分子内电荷转移特性的分子的结构与光物理性质的关系,研究体系为三苯胺作为电子给体,2,1,3-苯并噻二唑作为受体的单支分子及其对应的两支和三支分子. 并结合TD-DFT计算进一步解释了实验中所观察到的现象. 三个分子相似的吸收和荧光光谱以及强的溶剂依赖光谱特性表明两支与三支分子激发态与单支分子相似,表明激发态都定域在其中一支上. 激发时多支分子内发生多维电荷转移,然后快速地定域到某一支上发射. 另一方面多支分子相对于单支分子吸收和发射光谱的红     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Theoretical analysis and simulation of conjugate heights for dual-conjugate AO system in lidar

A multi-conjugate adaptive optics （MCAO） can offer a possibility of widening field of view （FOV） characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle＇s expressions of two deformable mirrors （DMs） MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.     

Quick single-photon detector with many avalanche photo diodes working on the time division

Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.