烟酸诺氟沙星和乳酸诺氟沙星的荧光特性及应用

研究了烟酸诺氟沙星和乳酸诺氟沙星在不同介质中的荧光特性。采用荧光分光光度法测定了烟酸诺氟沙星和乳酸诺氟沙星的含量。烟酸诺氟沙星和乳酸诺氟沙星分别在0.025—2.5μg/mL和0.01—2μg/mL范围内,其荧光强度与浓度线性关系良好。     

结晶紫-紫外分光光度法测定食品中糖精钠的含量

pH7.0的Britton-Robinson(B-R)缓冲溶液中,结晶紫在250nm波长处有最大吸收,少量糖精钠的存在可使结晶紫在该波长处的吸收峰显著增强。在0.008-44μg/mL范围内,体系的吸光度的增强与糖精钠浓度呈良好的线性关系(r=0.9994),检出限为0.004μg/mL,回收率在98.1%-108.3%之间,该法用于食品中糖精钠含量的测定,与国标法(高效液相色谱法)对照,结果满意。     

荧光分光光度法定量分析OP乳化剂

通过对OP(聚乙二醇辛基苯基醚)乳化剂的荧光光谱研究,发现其在304nm处产生较强的荧光.在pH 5.5的B-R缓冲溶液中,OP乳化剂的荧光强度与其浓度在一定范围内呈良好的线性关系,据此建立了一种新的高灵敏度的测定方法.在0.1-50.0μg/mL的浓度范围内,测定波长λex/λem=226nm/304nm的回归方程为:F=22.12C+9.825(C:μg/mL,r=0.9995),检出限为0.068μg/mL;测定波长λex/λem=276nm/304nm的回归方程为:F=90.08C-10.12 (C:μg/mL,r=0.9999),检出限为0.053μg/mL.采用此两组测定波长对同组样品进行测定,样品回收率均在96.5％以上,对测定结果进行F检验和t检验分析,得出两组数据之间无显著性差异.方法灵敏度高,抗干扰能力较强,可用于测定较复杂环境样品中微量OP乳化剂含量.     

荧光法直接测定环境水中邻羟基苯甲酸和苯酚混合物的含量

本文研究了用荧光分光光度法测定环境水中苯酚和邻羟基苯甲酸的含量,在pH＞11时直接测定邻羟基苯甲酸的含量,波长为λex/λem=289/338nm,检出限为3.4ng/mL,线性范围0-6.0μg/mL.在pH=6,波长为λex/λem=270/297nm测得苯酚含量,检出限为4.0ng/mL,线性范围在0-0.85μg/mL,回收率为98%-101%,结果满意.     

依诺沙星的荧光熄灭法测定

基于依诺沙星对十二烷基苯磺酸钠的荧光具有猝灭的特性,建立了一种测定依诺沙星的新方法。在pH2.00的磷酸缓冲溶液中,十二烷基苯磺酸钠的激发波长为283nm,发射波长为326nm,依诺沙星的浓度在0—8.1μg/mL范围内与其荧光强度呈良好的线性关系,检出限为0.016μg/mL,方法的相对标准偏差为1.17%。本法灵敏度高、选择性好,用于制剂中依诺沙星的含量测定,结果令人满意。     

荧光猝灭光谱法测定DNA

利用荧光光谱法对5-邻氯乙酰氧基苯基-10,15,20-三苯基卟啉与脱氧核糖核酸（DNA）在不同条件下的荧光光谱特征进行了研究。实验表明,在低离子强度下,小牛胸腺DNA导致卟啉的荧光强度猝灭。在pH4.4的B-R缓冲介质中,荧光猝灭程度与小牛胸腺DNA的浓度呈线性关系,线性方程为ΔF=29.8C（μg/mL）-1.17,线性范围为0—10μg/mL,检出限为1.22μg/mL,相关系数为0.9949。对提取的植物基因组总DNA进行测试,由线性方程求得样品中的DNA含量。     

水杨基荧光酮荧光熄灭法测定痕量铝

研究了在羟丙基-β-环糊精(HP-β-CD)和乳化剂(OP)存在下,在NaAc-HAc介质中,以水杨基荧光酮(SAF)作为荧光试剂,用荧光熄灭法测定痕量铝的新方法;体系的最大激发波长和发射波长分别为365nm和522nm,25mL溶液中,Al(Ⅲ)含量在0.028-4.0μg/25mL范围内符合线性关系,方法检出限为1.11μg/L.干扰离子较少,已用于自来水中痕量铝的测定,结果令人满意.     

铈(V)与左旋多巴的荧光反应及其分析应用

研究了左旋多巴与Ce(Ⅳ)在碱性体系中的荧光特性.实验发现,左旋多巴具有弱的内源性荧光,在pH为9.15的伯瑞坦-罗比森Britton-robinson(BR)缓冲介质中可与Ce(Ⅳ)发生反应,使其荧光强度显著增强,据此提出了测定左旋多巴含量的荧光分析新方法.左旋多巴含量在0.08-3.6μg/mL范围内与其荧光强度呈...     

荧光素汞荧光熄灭法测定海带中微量碘

本文研究表明，在pH=6.0-11的磷酸协缓冲溶液中，碘离子对荧光素汞的荧光具有熄灭作用，据此建立了碘离子的荧光熄灭测定新方法。碘离子浓度在0．0768－4．365μg/mL范围内具有良好的线性关系，检出限为0．038μg/mL。该方法操作简单，灵敏度高，选择性好，可用于海带中碘含量的测定。     

荧光光谱法快速测定餐巾纸中的可迁移荧光增白剂

建立餐巾纸中可迁移荧光增白剂含量测定的荧光光谱法.在模拟人体温37℃的实验温度下,在餐巾纸中加入一定体积的二次去离子水,通过静置和振荡两种不同的萃取方式处理后,用荧光光谱法测定可迁移荧光增白剂含量.测定线性方程:y=1.564x+0.054,R2=0.9946,检出限为0.30μg/g,RSD为0.6％-9.8％.该法灵敏度高,且简单、快捷,适用于餐巾纸中可迁移荧光增白剂含量的快速测定.     

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.     

Hybrid Wavelength and Code Division Multiple Access in Optical Networks

A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.     

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.     

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.     

Research on beamforming method for dual-line array with space mismatch between the two line arrays

The performance of port/starboard discrimination of dual-line array will be seriously degraded when the space between the two line arrays of the dual-line array is mismatched. The directivity function of the delay-sum and delay-subtract beamforming is deduced and the port/starboard discrimination of the delay-sum and delay-subtract beamforming is also studied both under the ideal status and the status under which the space between the two line arrays of the dual-line array is mismatched. Analysis results show the delay-subtract beamforming has better performance of port/starboard discrimination. At last, the sea trial results demonstrate the theoretical results.     

Retrieval of ultraviolet skylight radiances and O3 slant column densities from balloon-borne limb spectrometer

With a novel light-weight and absolutely calibrated ultraviolet （UV） spectrometer, UV skylight radiances and O3 slant column densities are measured by balloon-borne limb measurements in Xinjiang area, China. UV skylight radiances measured at the height of 31 km are compared with the results from Modtran in the wavelength range from 290 to 420 nm. O3 slant column densities are derived from radiance spectra in the Huggins bands （320 - 335 nm） using differential optical absorption spectroscopy method. And the parameter exhibits a good correlation with the same value simulated by radiative transfer model （Tracy）. The O3 profile simultaneously measured by an O3 sonde is used as input in Tracy calculations. The O3 sonde is launched on the same balloon.     

Design optimization of highly sensitive LSPR enhanced surface plasmon resonance biosensors with nanoholes

For breaking through the sensitivity limitation of conventional surface plasmon resonance (SPR) biosensors, novel highly sensitive SPR biosensors with Au nanoparticles and nanogratings enhancement have been proposed recently.But in practice, these structures have obvious disadvantages.In this study, a nanohole based sensitivity enhancement SPR biosensor is proposed and the influence of different structural parameters on the performance is investigated by using rigorous coupled wave analysis (RCWA).Electromagnetic field distributions around the nanohole are also given out to directly explain the performance difference for various structural parameters.The results indicate that significant sensitivity increase is associated with localized surface plasmons (LSPs) excitation mediated by nanoholes.Except to outcome the weakness of other LSP based biosensors, larger resonance angle shift, reflectance amplitude, and sharper SPR curves' width are obtained simultaneously under optimized structural parameters.     

Polymer gratings based on photopolymerization for low-order distributed feedback polymer lasers

Novel polymer distributed feedback(DFB)gratings are fabricated based on photopolymerization to reduce lasing threshold of polymer lasers.A photopolymer formulation sensitive to 355-nm ultraviolet(UV)light is proposed for the fabrication of polymer gratings and it can be used to form polymer films by spin-coating process.A very low surface-relief depth ranging from 12.5 to about 1.0 nm has been demonstrated with a refractive-index modulation of about 0.012.The experimental results indicate that such polymer gratings have promising potentials for the fabrication of low-order DFB organic semiconductor lasers.