阳离子表面活性剂与酚红的显色反应及其分析应用

研究了阳离子表面活性剂（ＣＳＡＡ）溴化十六烷基三甲铵（ＣＴＡＢ）、溴化十六烷基吡啶（ＣＰＢ）在水溶液中与溴酚红（ＢＰＲ）的显色反应。发现在ＰＨ５．０～６．０范围内,ＣＳＡＡ单体与ＢＰＲ形成离子缔合物（缔合比为３：２）,可用于微是ＣＳＡＡ及ＣＳＡＡ的临界胶束浓度（ＣＭＣ）的测定。本文还研究了显色２的适宜条件、分析特征,并讨论了反应机理。     

胶束体系中荧光素与四溴荧光素间能量转移条件及模型研究

研究了阳离子表面活性剂(CSAA)在水溶液中与阴离子酸性染料四溴荧光素(TBF)的荧光反应,发现当CSAA单体与TBF形成离子缔合物时,TBF的荧光发生猝灭,而CSAA胶束与TBF作用又会产生一个新的、更强的荧光。进而研究了阳离子表面活性剂CTMAB及CPB胶束体系中酸性阴离子荧光染料荧光素与四溴荧光素间的能量转移条件。表明只有在带相反电荷的CSAA形成的胶束中,阴离子染料间的能量转移才可能发生,在2/3临界胶束浓度(CMC)时能量转移效率达到最大。并推测了胶束体系中染料间能量转移模型及染料间能量转移的一般规律。     

铀-Br-PADAP-磺基水杨酸-表面活性剂体系的研究

本文研究了铀(Ⅵ)-Br-PADAP-磺基水杨酸三元络合物分别与阳离子表面活性剂溴化十六烷基吡啶(CPB)、溴化十六烷基三甲基铵(CTAB),非离子表面活性剂聚乙二醇辛基苯基醚(OP),Triton X-100的反应条件、生成物的性质和其组成,对反应机理进行了初步讨论。     

4,5—二溴邻硝基苯基荧光酮分光光度法测定铁

本文研究了4,5-二溴邻峭基苯基荧光酮在阳离子表面活性剂溴化十六烷基三甲基铵存在下,测定微量铁的显色反应。4,5-二溴邻硝基苯基荧光酮,溴化十六烷基三甲基铵与铁形成稳定的络合体系,在614纳米处有最大吸收峰,该法灵敏可靠(δ=1.47×10~5),选择性高,大部分常见元素不干扰。吸光值在24小时内不变,应用于白云石,水样及氧化镁中微量铁的测定,获得令人满意的结果。     

N2-苯浮选缔合光度法测定碘的研究

本文依据在强酸性磷酸介质中,Br2氧化I-为I2,进而与I-生成配阴离子I-3,利用溴化十六烷基三甲胺(CTMAB)与I-3发生等离子对缔合物反应,生成缔合物CTMA+*I-3,该缔合物易溶于苯,且在苯中稳定,从而建立了溶剂浮选光度法测碘新方法.本法灵敏度高,选择性强,精密度好,实测了天然水及加碘的盐中碘,结果令人满意.     

2-(2-喹啉偶氮)-1，5-苯二酚光度法测定铜的研究

合成了新试剂 2 - ( 2 -喹啉偶氮 ) - 1,5-苯二酚 ( QADHB) ,并研究了其与铜的显色反应 ,在溴化十六烷基三甲胺 ( CTMAB)存在下 ,p H=4 .0邻苯二甲酸氢钾缓冲介质中 ,QADHB与铜反应生成 2∶ 1稳定络合物 ,λmax=540 nm,ε=2 .12× 10 4 L·mol-1·cm-1。铜含量在 0— 30 μg/ 2 5m L内符合比耳定律 ,该方法用于环境样品中铜的测定 ,结果令人满意     

Fe(Ⅲ)-苯基荧光酮-溴化十六烷基三甲胺显色反应的研究与应用

本文研究了在溴化十六烷基三甲胺存在下，苯基荧光酮与铁的显色反应。试验结果表明，显色的适宜酸度为pH等于7.3至10．5，配合物的摩尔吸光系数为1．09×105L·mol-1·cm-1，铁量在0－6μg·25mL-1范围内符合比耳定律。用于试样中铁的测定，灵敏度高，且简便可靠。     

2-(2-喹啉偶氮)-4-甲基-1,3-苯二酚光度法测定铜的研究

合成了新试剂 2 - (2 -喹啉偶氮 ) - 4-甲基 - 1,3-苯二酚 (QAMDHB) ,并研究了其与铜的显色反应 ,在 p H=2 .2的磷酸 -磷酸二氢钾缓冲介质中 ,溴化十六烷基三甲基胺 (CTMAB)存在下 ,QAMDHB与铜反应生成 2∶ 1稳定络合物 ,λmax=5 5 0 nm,ε=4 .84× 10 4L· mol-1· cm-1。铜含量在 0— 2 0μg/ 2 5 m L范围内符合比耳定律 ,方法用于环境水样中铜含量的测定 ,结果令人满意     

甲基橙-溴化十六烷基吡啶分光光度法测定阴离子表面活性剂

在一定浓度的乙醇水溶液中,甲基橙(MO)可与溴代十六烷基吡啶(CPB)发生褪色反应,加入阴离子表面活性剂十二烷基硫酸钠(SDS),可使MO-CPB褪色体系增色,确定了显色体系的最大吸收波长为460nm.研究发现在最大吸收波长处,加入的SDS浓度与MO-CPB体系增色程度在一定范围内呈现良好的线性关系,当SDS的浓度在0...     

铌-酒石酸-铬天青S-溴化十六烷基吡啶分光光度法测定微量铌

研究了以酒石酸作为络合剂,铌与铬天青S及溴化十六烷基吡啶的显色反应及应用.吸光实验表明,在盐酸溶液中,Nb(Ⅴ)-CAS-CPB形成稳定的络合物,最大吸收波长为504nm,表观摩尔系数为2.1×106L·mol-1·cm-1.铌浓度在0-2.4μg/25mL范围内遵守比耳定律,相关系数为0.9989.该法测定铌钽矿中铌,测得铌的含量为0.502％.     

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.     

Characterization of PolyA and PolyC mismatches by Raman spectroscopy

A.C mismatches are studied by Raman spectral characterization of PolyA, PolyC, and their equimolar complex in solution of 0.14 mol/L Na ,pH7.0.Experimental results show that A·C mismatches occur to be A/B (mainly A) conformers, and unlike Watson-Crick base pairing, this kind of mismatches is stabilized by only one hydrogen bond involving cytosine N4H2 and adenine N7.The formation of A·C complex makes the base stacking interactions much stronger, and conformation of the backbone more ordered, which leads to obvious Raman hypochromic effect with some shifts in corresponding bands.     

Improvement of four-wave mixing-based wavelength conversion efficiency in dispersion shifted fiber by 40-GHz clock pumping

40-GHz clock modulated signal as a pump to improve the efficiency of four-wave mixing (FWM)-based wavelength conversion in a 26.5-km dispersion shifted fiber (DSF) is investigated. The experimental results demonstrate that the conjugated FWM component has higher intensity with the clock pumping than that with the continuous-wave (CW) light pumping. The improvement of FWM-based wavelength conversion efficiency is negligible when the pump power is less than Brillouin threshold. But when the pump power is greater than Brillouin threshold, the improvement becomes significant and increases with the increment of pump power. The improvement can increase up to 9 dB if pump power reaches 17 dBm.     

Multi-pulse operation of a Kerr-lens mode-locked femtosecond laser

Our experimental results show that the presence of a proper amount of negative group velocity dispersion is essential to multi-pulse operation of a Kerr-lens mode-locked femtosecond laser. We demonstrate that the pulse separations and the number of pulses contained within a cavity round trip are strongly dependent on the initial perturbations. The results allow us to get a better understanding on the influences of the convoluted self-phase modulation and intra-cavity dispersions on the stable multi-pulse oscillation in a Kerr-lens mode-locked femtosecond laser.     

Propagation of Helmholtz-Gauss beams in weak turbulent atmosphere

Based on the Rytov approximation of light propagation in weak turbulent atmosphere,the closed-form expressions of field and average irradiance of each one of the four fundamental families of Helmholtz-Gauss (HzG)beams:cosine-Gauss beams,stationary Mathieu-Gauss beams,stationary parabolic-Gauss beams,and Bessel-Gauss beams,which are propagating in weak turbulent atmosphere,are obtained.The results show that the field and average irradiance can be written as the product of four factors:complex amplitude depending on the z-coordinate only,a Ganssian beam.a factor of complex phase perturbation induced by atmospheric turbulence,and a complex scaled version of the transverse shape of the non-diffracting beam.The effect of weak atmospheric turbulence on irradiance distribution of the HzG beam can be ignored.     

An effective method for reducing speckle noise in digital holography

An effective method for reducing the speckle noise in digital holography is proposed in this paper.Different from the methods based on classical filtering technique,it utilizes the multiple holograms which are generated by rotating the illuminating light continuously.The intensity images reconstructed by a series of holograms generated by rotating the illuminating light possess different speckle patterns.Hence by properly averaging the reconstructed intensity fields,the speckle noises can be reduced greatly.Experimental results show that the proposed method is simple and effective to reduce speckle noise in digital holography.     

Influence of purity of HfO2 on reflectance of ultraviolet multilayer

The impurities in two kinds of HfO2 materials and in their corresponding single layer thin films were determined through glow discharge mass spectrum technology and secondary ion mass spectrometry(SIMS) equipment respectively.It was found that ZrO2 was the main impurity in the two kinds of HfO2 either in the original HfO2 materials or in the electron beam deposited films.In addition,the difference of Zr content in the two kinds of HfO2 single laver films was much laxger than that of the other impurities such as Ti and Fe.which showed that it was just ZrO2 that made the difference between the optical performance of the film products including the two kinds of HfO2.With these two kinds of HfO2 and the same kind of SiO2.we deposited HfO2/SiO2 multilayer reflective coatings at the wavelength of 266 nm.Experimental results showed that the reflectances of these two mirrors were about 99.85% and 99.15% respectively,which agreed well with the designed results what were based on the optical constants obtained from the corresponding single layer thin films.     

Speech enhancement by array crosstalk resistant ANC and spectrum subtraction

Microphone array-based speech enhancement has great importance for speech communications and speech recognition. To reduce the aperture of the microphone array and to increase the effect of the speech enhancement will greatly broaden the application areas of the microphone array. An array crosstalk resistant adaptive noise cancellation method is therefore presented. And then an improved spectral subtraction algorithm is further cascaded to obtain better enhancement results. Theoretic analysis and experiments indicate that the proposed scheme needs only a very small microphone array while it simultaneously achieves a higher SNR improvement. Besides, the proposed scheme can be used in many noisy environments and is easy for real-time implementation.