7-(苯并噻唑-2-偶氮)-8-羟基喹啉-5-磺酸与镉显色反应的研究和应用

在 p H4 .8的邻苯二甲酸氢钾 - Na OH介质中 ,非离子表面活性剂 Tween- 80存在下 ,7- (苯并噻唑 - 2 -偶氮 ) - 8-羟基喹啉 - 5 -磺酸 (BTAQS)与镉形成 2∶ 1的紫红色配合物 ,其最大吸收波长 λmax=5 6 0 nm,表观摩尔吸光系数为 8.71× 10 4L· mol-1·cm-1,镉含量在 0— 6 μg/ 10 m L范围内服从比耳定律。用于矿样中镉的测定 ,相对误差小于 3% ,相对标准偏差小于 2 .5 % (n=5 )。     

锌-苯基荧光酮-CTMAB体系条件研究及应用

研究了在 p H8.0的硼酸 -硼砂缓冲溶液中 ,有 CTMAB存在下 ,锌与 PF的显色反应。锌与 PF生成的红色络合物 ,最大吸收波长为 5 70 nm,表观摩尔吸光系数为 4 .90× 10 4 L·mol-1·cm-1,测得络合物的组成比 Zn( )∶ PF=1∶ 1。锌含量在 0— 2 0μg/ 2 5 m L之间符合比耳定律。有色络合物稳定 2 4 h以上 ,应用于矿石中微量锌的测定 ,获得了满意的结果     

溴化5-［4-(2-吡啶-乙氧基)苯基］-10，15，20-三苯基卟啉对铜离子的显色反应研究

本文研究了溴化 5- [4 - ( 2 -吡啶 -乙氧基 )苯基 ]- 10 ,15,2 0 -三苯基卟啉与 Cu2 +的显色反应条件 ,在 p H=4 .0时 ,其络合物最大吸收波长为 4 13nm,试剂最大吸收波长为 4 4 3.5nm。对比度大约为 30 nm。试剂与铜络合比为 1∶ 1,其络合物表观摩尔吸光系数为 3.4× 10 5L·mol-1· cm-1,铜含量在 0— 0 .5μg/ 10 m L范围内符合比耳定律 ,本研究可用于痕量铜的测定     

亚叶酸钙与对硝基酚荷移反应的研究

本文主要研究了在水溶液中亚叶酸钙与对硝基酚发生荷移反应生成稳定的 1∶ 1络合物 ,络合物的最大吸收波长为 4 0 2 .2 nm,表观摩尔吸光系数为 ε=5 .2 5 5× 10 2 L· mol-1· cm-1,线性范围为 5 0—12 0 0 μg/ m L。回收率为 99.5 8%— 10 2 .6 0 % ,相对标准偏差为 1.4 3%。方法简单、快速、准确度高 ,可用于亚叶酸钙制剂含量的测定。     

分光光度法测定中草药中的槲皮素

在表面活性剂 Triton X- 10 0的存在下 ,于 p H4 .5 HAc- Na Ac缓冲溶液介质中 ,槲皮素与镓形成 2∶ 1的黄色络合物 ,由此建立了用分光光度法测定中草药中槲皮素含量的新方法。槲皮素的检出限为1.2 6× 10 -7mol· L-1,线性范围为 6 .30× 10 -7— 1.86× 10 -6mol· L-1,RSD<4 .1%。与 AFS法比较测定结果一致     

对硝基酚荷移分光光度法测定甲氧苄啶的含量

在水溶液中甲氧苄啶与对硝基酚发生反应生成 1∶ 1的荷移络合物。络合物最大吸收波长 4 0 2 .4 nm,线性范围 2— 2 5 μg/ m L,表观摩尔吸光系数为 ε=8.4 6 8× 10 3 L· mol-1· cm-1,回收率为99.6 7%— 10 0 .4 % ,相对标准偏差为 1.3% (n=5 )。本法测定甲氧苄啶药物制剂含量 ,结果令人满意。     

分光光度法测定水中的痕量镍

研究了在非离子表面活性剂 Triton X- 10 0存在下 ,在 p H 10 .5的 Na2 B4 O7- Na OH介质中 ,镍 ( )与显色剂 1- ( 4 -硝基苯 ) - 3- ( 2 -吡啶 ) -三氮烯 ( NPPy T)发生灵敏的显色反应 ,生成 1∶ 2的络合物 ,摩尔吸光系数ε=1.0 2× 10 5L· mol-1· cm-1,在 0— 2 0μg/ 2 5 m L范围内服从比耳定律。方法应用于水中微量镍的测定 ,结果令人满意     

钼-二溴邻硝基苯基荧光酮-CTMAB体系的分光光度法研究

研究了 1.2 mol· L-1的盐酸溶液中 ,有 CTMAB存在下 ,钼与 DBON- PF的显色反应。钼与 DBON- PF生成红色络合物 ,最大吸收波长为 540 nm,摩尔吸光系数为 6.2× 10 4 L·mol-1·cm-1。测得络合物的组成比为 Mo( )∶ DBON- PF=1∶ 2。钼量在 0— 2 0 μg/ 2 5m L范围内符合比耳定律。有色络合物稳定 8h以上。该方法用于矿石中微量钼的测定 ,结果令人满意。     

微波消化-固相萃取光度法测定生物样品中的钴

根据 2 - (2 -喹啉偶氮 ) - 1,5 -苯二酚 (QADHB)与钴的显色反应及 C18固相萃取小柱对显色络合物的固相萃取 ,建立了一种测定生物样品中痕量钴的新方法。在 p H=4 .0的 HAc- Na Ac缓冲介质中 ,溴化十六烷基三甲基铵 (CTMAB)存在下 ,QADHB与钴反应生成 2∶ 1稳定络合物 ,该络合物可用 C18固相萃取小柱富集 ,小柱上富集的络合物用乙醇 (内含 2 %乙酸 )洗脱后用光度法测定 ,络合物最大吸收波长为5 80 nm,钴含量在 0— 0 .8μg/m L范围内符合比耳定律 ,摩尔吸光系数 ε=5 .6× 10 4L· mol-1·cm-1。本方法用于几种生物样品的分析 ,结果令人满意。     

微波消化-分光光度法测定烟草中的镁

研究了偶氮氯膦 - 与镁的显色反应 ,在 p H=10 .0硼砂 -氢氧化钠缓冲介质中 ,偶氮氯膦 - 与镁反应生成 1∶ 1稳定的络合物 ,λmax=6 10 nm,ε=2 .34× 10 4L· mol-1· cm-1。镁含量在 0— 15μg/ 2 5 m L范围内符合比耳定律 ,结合微波消化样品技术 ,建立了一种烟草样品中镁含量的测定方法 ,结果令人满意     

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.     

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.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.