流动注射化学发光法测定邻苯二酚

基于在甲醛存在下 ,邻苯二酚与高锰酸钾在酸性介质中发生化学发光反应 ,建立了测定邻苯二酚的流动注射化学发光分析法 ,该法测定邻苯二酚的线性范围为 3.0× 10 -8— 1.0× 10 -5mol/L,检出限为 1.0× 10 -8mol/L,相对标准偏差为 3.5 % (1.0× 10 -6mol/L邻苯二酚 ,n=11)。该法应用于测定自来水中加入的邻苯二酚 ,结果令人满意     

流动注射化学发光增强法测定焦性没食子酸

在较低 p H值的 Na OH介质中 ,焦性没食子酸对 Luminol- K3 Fe(CN) 6化学发光体系有很强的增敏作用 ,据此建立了焦性没食子酸的测定方法——流动注射化学发光增强法。该法的化学发光增强值 (ΔI)与焦性没食子酸浓度 (在 3.0× 10 -9— 1.0× 10 -6mol/ L范围内 )呈良好的线性关系 ,检出限为 1.0× 10 -9mol/ L(n=11) ,对 5× 10 -8mol/ L焦性没食子酸测定的相对标准偏差为 2 .8%。用于没食子酸热解产物中的焦性没食子酸测定 ,结果令人满意     

5-甲氧基色醇-酸性高锰酸钾-甲醛化学发光体系研究与应用

在甲醛的存在下 ,5 -甲氧基色醇 (5 - ML)与高锰酸钾在高氯酸介质中发生化学反应 ,能产生很强的化学发光。本文据此采用流动注射技术研究其发光行为 ,对影响化学发光强度的实验因素进行优化 ,建立了快速灵敏测定 5 - ML的化学发光新方法 ,测定方法的线性范围为 2 .0× 10 -8mol/ L— 4 .0× 10 -5mol/ L,检出限为 7.9× 10 -9mol/ L(S/ N=3) ,相对标准偏差为 2 .4 % (5 .7× 10 -7mol/ L5 - ML;n=10 )。该方法应用于脑脊液样品中 5 - ML含量测定 ,回收率达到 86 .0 %— 97.2 %。文中还对体系的化学发光反应机理进行探讨     

鲁米诺化学发光熄灭法测定稀土镧的研究

本文研究了稀土La（Ⅲ）对Luminol-H2O2-Cr(Ⅲ)化学发光体系的熄灭效应，在此基础上建立了稀土镧的流动注射化学发光分析法，方法的检出限为4×10^-8mol/L；对于2×10^-7mol/L稀土镧标准溶液测定的相对标准偏差为3.0%（n＝11）；线性范围为1.0×10^-7-1.0×10^-4mol/L；相关系数大于0.9984，该法用于合成样品分析，结果满意。     

化学发光法测定水中1-溴-3-氯-5,5-二甲基海因

基于在碱性条件下 (p H 12 .0— 12 .5 ) 1-溴 - 3-氯 - 5 ,5 -二甲基海因与鲁米诺 -过氧化氢体系反应产生化学发光的性质 ,建立了一种测定其含量的新方法。 1-溴 - 3-氯 - 5 ,5 -二甲基海因的浓度在 4 .0× 10 -8— 1.0×10 -6mol/ L范围内与化学发光强度呈良好的线性关系。本方法的线性范围宽 ,灵敏度高 ,检出限为 2 .0×10 -8mol/ L。操作简单、方便。应用于游泳池水中 1-溴 - 3-氯 - 5 ,5 -二甲基海因的测定 ,结果令人满     

光泽精化学发光体系的研究与应用

对光泽精化学发光体系的动力学性质、荧光光谱、化学发光光谱及化学发光机理进行研究和探讨。详细研究了光泽精 - H2 O2 - Co( )流动注射化学发光体系的最佳分析条件。结果表明 ,当光泽精 (L c)为 2 .5×10 - 5mol/L、H2 O2 为 0 .5 mol/L、Na OH为 0 .4 mol/L、CTMAB为 2 .0× 10 - 5mol/L时 ,测定 Co( )的校准曲线线性范围为 0 .0 5— 2 0 0μg/m L ,检出限为 0 .0 1μg/m L。对 10μg/m L Co( )连续测定 7次 ,相对标准偏差为 1.7%。     

荧光光度法测定胰腺肿瘤细胞膜上的潘生丁

测定了胰腺肿瘤细胞膜上的潘生丁在乙腈 -水溶液中的荧光光谱和强度 ,并推算出胰腺肿瘤细胞膜上核苷载体的数量。潘生丁的浓度与其荧光强度在 1.0× 10 -12 — 5 .0× 10 -5mol/ L范围内呈线性关系 ,检出限为 2 .8× 10 -13 mol/ L(1.4× 10 -4ng/ m L) ,相对标准偏差为 2 .7%。     

单扫描极谱法测定有机锗(Ge-132)

在 p H2 .0的 K2 SO4 介质中 ,有机锗 (Ge- 132 )在单扫描示波极谱仪上于 - 0 .13V(vs.Ag Cl/ Ag)和- 1.0 5 V(vs.Ag Cl/ Ag)处产生两个还原波 ,其中 - 1.0 5 V(vs.Ag Cl/ Ag)波灵敏、波形好。峰电流与 Ge-132在 1.0× 10 - 5— 5 .0× 10 - 4mol/ L范围内呈良好的线性关系 ,其检出限为 8.9× 10 - 5mol/ L。该方法用于有机锗营养口服液中 Ge- 132的测定 ,结果较好     

化学发光抑制法测定抗坏血酸

利用抗坏血酸对DTMC H2 O2 化学发光体系的抑制作用 ,研究了对抗坏血酸进行间接测定的可能性。试验发现 ,化学发光猝灭率 (R)与抗坏血酸浓度在 1 0× 10 - 7～ 8 0× 10 - 6 mol·L- 1 范围内呈线性关系 ,检出限达到 8 0× 10 - 8mol·L- 1 (S N =3)。对 1 0× 10 - 6 mol·L- 1 抗坏血酸进行 10次平行测定 ,其化学发光强度猝灭率相对标准偏差为 4 6 %。该猝灭体系不需要额外的掩蔽剂 ,方法简单、选择性好 ,可直接应用于一些食品中微量抗坏血酸的测定。     

黄嘌呤氧化酶-乙醛-吖啶酯化学发光分析新体系

乙醛在黄嘌呤氧化酶催化作用下,被空气氧化生成乙酸和过氧化氢,酶反应生成的过氧化氢氧化新吖啶酯试剂[10-甲基-9-(对甲酰苯基)吖啶羧酸酯氟磺酸盐]产生化学发光,化学发光强度与己醛浓度在一定范围内成线性关系.由此建立了一种化学发光分析新体系,用于测定乙醇含量.线性范围2.0×10-7～1.2×10-3mol/L,测定5.0×10-7mol/L乙醛,相对标准偏差为6.8%,检测限为1.2×10-7mol/L,测定环境水样中乙醇含量,取得满意结果,回收率为95～106%.     

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.     

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.     

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.     

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.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.