流动注射-化学发光法定量测定同一水域中的腐殖酸

采用流动注射-化学发光(FI-CL)这一灵敏的检测方法,通过条件实验与参数优化,优选了测定环境中痕量多羟基酚类化合物的发光体系,通过考察天然水体中的腐殖酸对化学发光-多羟基酚测定体系的影响,为来自于水及土壤中的实际样品中腐殖酸的检测提供了参考,建立了同一区域水体中腐殖酸的化学发光定量测定方法。 所得线性回归方程y=70.36x+540.1,相关系数r=0.995 4,线性范围为3～15 mg·L-1,检测限为0.749 mg·L-1,HA浓度为6 mg·L-1时的相对标准偏差(RSD)为1.08%。     

流动注射化学发光测定间苯三酚

基于在甲醛存在条件下,高锰酸钾在酸性介质中氧化间苯三酚而直接产生化学发光,结合流动注射技术建立了测定间苯三酚的化学发光分析方法,该法测定间苯三酚的线性范围为5.0×10-9～5.0×10-5 mol·L-1,检出限为3.0×10-9 mol·L-1,相对标准偏差为2.5%(1.0×10-6 mol·L-1间苯三酚,n=11)。该法应用于测定在几种实际水样中加入的间苯三酚,回收率令人满意。     

化学发光法测定左氧氟沙星

利用左氧氟沙星对碱性luminol H2 O2 化学发光体系具有强的增敏作用 ,建立了一种测定左氧氟沙星的新方法。方法的线性范围为 5 5 3× 10 - 1 1 ～ 2 2 1× 10 - 8mol·L- 1 ,检测限 (3σ)为 1 38× 10 - 1 1 mol·L- 1 ,RSD为2 5 6 % (n=9)。该法用于胶囊的测定 ,结果满意。     

化学发光法测定巯嘌呤的含量

在流动注射系统中,利用巯嘌呤在碱性Luminol-K₃Fe(CN)₆化学发光体系中发光信号强的特点,建立了一种测定巯嘌呤的新方法。在优化条件下,方法的线性范围是1.02×10-7～1.02×10-9mol·L-1, 回归方程是Y=36.315c+140.72(Y是相对发光强度,c是巯嘌呤浓度与10-8 mol·L-1的乘积), 相关系数是0.998 2,检出限(S/N=3)是6.33×10-10mol·L-1,RSD为3.54%（c_i=2.0×10-9mol·L-1, n=12）。该法用于合成样品的测定,简便、灵敏、快速,结果令人满意。文章简要地探讨了巯嘌呤在碱性Luminol-K₃Fe(CN)₆化学发光体系中的化学发光机理：在反应过程中,产生大量的过氧自由基和羟基自由基,自由基与鲁米诺反应,形成激发态的鲁米诺分子,鲁米诺分子由激发态回到基态产生化学发光现象。     

流动注射化学发光法测定L-乳酸铝

发现L-乳酸铝对纳米金-酸性高锰酸钾体系化学发光的增强作用,其增强化学发光强度的能力与高锰酸钾及溶液的介质硫酸浓度、金浓度以及蠕动泵的转速、流动注射化学反应体系的流路设计等因素有关,在此基础上首次建立了测定L-乳酸铝的增强化学发光分析法。测定L-乳酸铝的线性范围为7.0×10-5～1.0×10-2g.mL-1,检出限为1.04×10-6g.mL-1(S/N=3),对8.0×10-4g.mL-1的L-乳酸铝标准溶液进行11次平行测定,相对标准偏差(RSD)为1.48%。该法直接用于L-乳酸铝制备合成反应液以及分离纯化废液中L-乳酸铝的测定,其回收率为95.8%～100.4%,本法与GB/T6987.8-2001法进行了对照,结果令人满意。探讨了该化学发光增强作用是由于L-乳酸铝注入体系后,加速了纳米金与酸性高锰酸钾的反应所致。     

阿莫西林的荷移光谱测定方法研究

在丙酮介质中阿莫西林与 7,7,8,8-四氰基对二次甲基苯醌 (TCNQ)荷移反应 ,形成 1∶ 1络合物 ,在74 4nm和 84 5 nm处有较强光吸收 ,表观摩尔吸光系数分别为 1.2× 10 4L· mol-1· cm-1和 1.8× 10 4L·mol-1· cm-1,阿莫西林的浓度在 10— 15 0 mg· L-1范围内符合比耳定律。在乙醇介质中 ,阿莫西林与对苯醌 (p- BQ)反应 ,形成 1∶ 1络合物 ,最大吸收波长为 4 80 nm,表观摩尔吸光系数为 1.92× 10 3 L· mol-1·cm-1。阿莫西林的浓度在 2 0— 2 0 0 mg·L-1范围内符合比耳定律。两种方法相对标准偏差分别为 1.2 %和1.5 % (n=8) ,用于测定阿莫西林制剂的含量 ,结果与标准方法一致。     

流动注射化学发光快速测定空气中甲醛

基于甲醛对Luminol-H2O2化学发光体系的增敏作用,建立了快速、简便、灵敏度高的流动注射-化学发光测定甲醛的新方法.测定甲醛的线性范围:0.1×10-12-10.0×10-12mol·L-1;检出限:0.03×10-12mol·L-1(3σ),RSD小于3%(n=5).本法成功的测定了空气和血清中甲醛的含量,采用标准加入法,回收率为94.28%-113.20%.     

吖啶橙-罗丹明B二聚体能量转移体系在DNA测定中的应用及机理研究

首次研究了吖啶橙 罗丹明B二聚体能量转移体系作为荧光探针用于DNA的测定 ,并对其机理进行了探讨。用于鲱鱼精DNA和小牛胸腺DNA的测定 ,线性范围分别为 0 33～ 1 33mg·L- 1 ,0 33～ 3 33mg·L- 1 ,检测限分别为 1 6 3× 10 - 3mg·L- 1 ,1 5 2× 10 - 3mg·L- 1 。对 1 0 0mg·L- 1 鲱鱼精DNA和小牛胸腺DNA的测定 ,相对标准偏差分别为 2 4 %和 2 0 %。     

溴酚蓝测定血清白蛋白质的研究

用酸性染料为探针对蛋白质的定量已应用于临床医学及生命科学的研究中,本文利用分光光度法研究溴酚蓝(BPB)与牛血清白蛋白(BSA)、人血清白蛋白(HSA)的反应。在pH=2.79的Britton-Robinson缓冲溶液中,血清白蛋白与溴酚蓝通过分子间力形成蓝色复合物使吸光度增加。λ=605 nm时,εBSA=5.20×10~5L·(mol·cm)-1,εHSA=5.12×10~5L·(mol·cm)-1;BSA在0-78.0 mg·L-1,HSA在0-81.6 mg·L-1范围内服从比尔定律。检出限分别为BSA:2.93 mg·L-1,HSA:3.12 mg·L-1。对7个人血清蛋白总量平行6次测定,相对标准偏差1.2％-3.1％,回收率91.9％-105.6％。     

化学发光法测定尿酸

利用尿酸对碱性luminol-H₂O₂-Co2+化学发光体系具有较强的抑制作用,建立了一种测定尿酸的新方法。方法的线性范围为1.0×10-10～7.0×10-6 mol·L-1,检测限(3σ)为1.1×10-11 mol·L-1,RSD 1.9%(n=4,ｃ_s=5.0×10-8 mol·L-1)。该法用于人体血清及尿液中尿酸的测定,结果满意。     

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.