双水相体系中Cu(Ⅱ)的显色反应研究

本文研究了铬黑Ｔ（ＥＢＴ）作萃取剂和显色剂,在聚乙二醇－２０００（ＰＥＧ）－Ｎａ２ＳＯ４－ＥＢＴ双水相体系中Ｃｕ（Ⅱ）的显色反应条件及应用,实验结果表明,在ｐＨ８．５缓冲溶液中,将Ｃｕ（Ⅱ）络合物从水溶液中萃取到ＰＥＧ相,其最大吸收波长位于５６０ｎｍ,摩尔吸光系数为３．０５×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,此法用于铝合金中铜的测定,获得了满意结果。     

β修正光度法测定微量成分及络合比研究：Fe（Ⅱ）－EBT显色体系

在ｐＨ４－５ＨＡｃ－ＮａＡｃ溶液中，Ｆｅ（Ⅱ）与铬黑Ｔ（ＥＢＴ）反应，显色液由蓝变红色。反应较灵敏，ＥＤＴＡ和硫脲可使反应对Ｆｅ２＋具有选择性。本文研究β修正光度法测定微量铁并计算其络合比，该方法能消除显色液中过量显色剂干扰，提高测定灵敏度、准确度和精密度，测定结果表明，铁－ＥＢＴ络合比１：２，相对标准偏差ＲＳＤ≤４．３％，回收率９０．７～１０８％。适合于水及矿石、食品中铁的分析。     

胆红素铬合物的表面增强拉曼光谱研究

本文通过对近红外激发傅里叶变换拉曼光谱（ＮＩＲ－ＦＴ－Ｒａｍａｎ）与表面增强拉曼散射（Ｓｕｒｆａｃｅ Ｅｎｈａｎｃｅｄ Ｒａｍａｎ Ｓｃａｔｔｅｒｉｎｇ,ＳＥＲＳ）技术的联用,没得胆红素及其络合物Ｎａ２ＢＲ,ＣａＢＲ与ＣｕＢＲ在银溶胶中的ＳＥＲＳ光谱。结果表明,这一类与胆结石密切相关的生物分子络合物具有不同的配位方式,且在银胶表面采取不同的吸附取向,并从配位化学角度初步解释了黑色结石的黑色成因。     

双波长β修正光度法测定铁－二甲酚橙络合物特性参数

双波长β修正光度法是经过大量实验证实的一种有效的痕量金属分析方法，它能完全消除络合物反应中过量络合剂的影响，计算出络合产物的其实吸光度，进而建立络合物特征参数：组成比γ、真实摩尔吸光系数εｐ的计算方程。本文对Ｆｅ（Ⅲ）与二甲酚橙（ＸＯ）络合显色体系进行实验研究，结果表明其组成比γ＝１∶１，εｐ＝１．６３×１０４（Ｌ／ｍｏｌ．ｃｍ）。     

析相光度法测定铜（Ⅱ）的研究

本文研究了Ｃｕ－ＰＥＧ－ＤＤＴＣ（铜试剂）（ＮＨ４）２ＳＯ４体系的析相光度法并应用于测定Ｃｕ。最宜酸度为３．６－９．０（ＮａＡｃ－ＨＡｃ，ＮＨ４Ｃｌ－ＮＨ３．Ｈ２Ｏ）缓冲溶液，其络合物的最大吸收位于４５０ｎｍ，表观摩尔吸光系数为９．０５×１０＾３Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，Ｃｕ浓度在０－３０μｇ／Ｌ范围内服从比耳定律，铜与ＤＤＴＣ形成组成为１：２的稳定络合物。该方法用于铝合金中铜的测定，获得了满     

新试剂5—（2,4—二甲苯偶氮）—罗丹宁与银的显色反应的研究及应用

新试剂５－（２，４－二甲苯偶氮）－罗丹宁，在ｐＨ７．０５的ＮＨ４ＡＣ缓冲液中，当有非离子表面活性剂ＴｒｉｔｏｎＸ－１００存在时，银可与试剂形成１：１的络合物，其络合物的最大吸收波长位５２０ｎｍ，表观摩尔吸光系数εｏ ９．６×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，Ａｇ量在０－１０μｇ／２５ｍＬ范围内遵循比耳定律，所拟方法用于工业废水中微量银的测定，结果满意。     

双波长分光光度法测定铜及其络合物特征参数

在ｐＨ４．５醋酸盐缓冲溶液中，铜（Ⅱ）与氯磺酚Ｓ（ＳＣＰＳ）发生灵敏显色反应，生成蓝色络合物。本文应用β修正光度分析原理，研究此显色反应双波长测定废水中微量铜，分析灵敏度和准确度均比普通光度法有所提高，而且，络合物的络合比，实际摩尔吸光系数和不稳定常数均能够准确而简单地测得。结果表明，在铜浓度为０－０．８０ｍｇ／Ｌ范围内，符合朗白－比尔定律，铜最低测定浓度为０．０３ｍｇ／Ｌ。对样品分析，铜的加标回收率为９３．５％—１０９％，相对标准偏差ＲＳＤ≤３．７％。     

硫酸锰等样品中微量铁的分析研究

在ＰＨ１．５的氯乙酸介质中,铁（Ⅲ）与５－Ｂｒ－ＰＡＤＡＰ生成紫色络合物,表观摩尔吸光系数为６．０＊１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,最大吸收波长为５８８ｎｍ,铁含量在０－１５μｇ／２５ｍＬ范围内符合比耳定,该方法灵敏、简便,用于测定硫酸锰等样品中微量铁的测定,结果令人满意。     

BaFCl∶Eu~（2＋）中F色心的浓度和光激励截面与温度和紫外线的辐照波长的关系

本文研究了ＢａＦＣｌ∶ＥＵ（２＋）在不同波长的紫外线辐照和不同的测定温度下的光激励发光性质．通过改变激励方式及激励光的扫描方向，给出了ＢａＦＣｌ∶Ｅｕ（２＋）光激励发光过程中，两种Ｆ色心的浓度比值和光激励截面比值与紫外线辐照波长和测定温度的关系．同时我们还研究了在激励读出过程中，对应两种Ｆ色心的光激励发光强度与激励温度的关系，并且给出了相应于Ｆ（Ｃｌ－）心的热激活能．     

萘相萃取双波长分光光度法测定微量铜的研究

本文用蔡作萃取剂，以５－Ｂｒ－ＰＡＤＡＰ为显色剂，采用双波长分光光度法测定微量铜的研究。研究表明，选择５４０－３８３ｎｍ，为测定波长时，络合物最大吸收峰为５４０ｎｍ，表观摩尔吸光系数为１．２６×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，铜量在０－５．０μｇ／７ｍＬ范围内符合比耳定律，方法应用于食品，水样品铜的测定，结果满意。     

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.     

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.     

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.     

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.