铬天青S-OP分光光度法测定碳酸镍中微量铝

在ＨＡｃ－ＮＨ４Ａｃ缓冲介质中,乳化剂ＯＰ存在下,铝与ＣＡＳ形成灵敏度很高的绿色络合物,测定波长位于６２０ｎｍ,ε６２０＝１．０９×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１。碳酸镍中Ｆｅ＾２＋对测定有干扰外,其它的杂质元素均干扰,方法具有较好的选择性。Ｆｅ＾３＋的干扰,可采用抗坏血酸还原Ｆｅ＾３＋成Ｆｅ＾２＋而消除,５ｍｇ以下Ｎｉ对无明显影响,但当Ｎｉ量大于此量时,络合物吸光度下降,产生负干扰,本法采     

P538萃取锰（Ⅱ）的研究

在２５±０．５℃，用Ｐ５３８的环己烷溶液从ＮａＣｌＯ４－ＨＣｌＯ４介质中萃取Ｍｎ（Ⅱ）的反应机理为离子交换机理，萃取焓△Ｈ＝－１９６ｋＪ．ｍｏｌ＾－１并用Ｃｌ＾－离子水合作用和Ｍｎ＾２＋与Ｃｌ＾－形成配合物的竞争解释了萃取分配比与水相中ＮａＣｌ浓度的关系。     

罗丹明6G.四溴荧光素双显色体系浮选光度法测定锗的研究

向锗与茜素氨羧络合剂罗丹明６Ｇ形成的Ｇｅ（ＡＷＬＣ３（Ｒ６Ｇ）５甲苯浮选物，加入０．１ｍｏｌ／Ｌ的ＮａＯＨ的溶液，使Ｒ６ＧＹ颜色相同的四溴荧光互，形成等色染料离子对Ｒ６Ｇ＾＋；ＴＢＦ＾－再被甲苯浮选。将浮先物溶于丙酮，于５３０处进行光度测定，由于１０个染料分子同时吸光，使本方法具有很高的灵敏度：ε＝５．８×１０＾５Ｌ．ｍｏｉｌ＾－１，ｃｍ＾－１，锗含量在０．００４０－０．１ｍｇ／Ｌ服从比耳定律。     

2—溴甲基萘荧光和室温磷光性质研究

研究了２－溴甲基萘（２－ＢｒＭＮ）的荧光及磷光性质。２－溴甲基萘是一种优良的荧光试剂,λｅｘ／λｅｍ＝２７４／３３４ｎｍ,其浓度在１．０×１０＾－６～１．２×１０＾－４ｍｏｌ·Ｌ＾－１范围内与荧光强度呈良好的线性关系,相关系数ｒ＝０．９９９,最低检测限为４．７×１０＾－８ｍｏｌ·Ｌ＾－１。以β－环糊精（β－ＣＤ）作保护剂和１,２－二溴丙烷（ＤＢＰ）为重原子微扰剂的２－ＢｒＭＮ／β－ＣＤ／ＤＢＰ体系     

5-(H-酸偶氮)-8-氨基喹啉与铜显色反应研究及在烟草分析中的应用

本文研究了５－（Ｈ－酸偶氮）－８氨基喹啉（ＨＡＱ）与铜的显色反应,在ＰＨ＝４．２ＨＡｃ－ＮａＡｃ缓冲介质中,有乳化剂－ＯＰ存在下,ＨＡＱ与铜反应生成稳定的２：１络合物,λｍａｘ＝５５０ｎｍ,ε＝４．８７＊１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１。铜含量在０－１６μｇ／２５ｍＬ范围内符合比耳定律,方法用于烟草样品中铜含量的测定,结果令人满意。     

结合重金属前后浮萍的红外光谱比较

对结合ＺｎＳＯ４前后浮萍的红外光谱图进行了比较。结构Ｚｎ＾２＋后,３４００ｃｍ＾－１附近的羟基峰发生了位移（△υ＝８３ｃｍ＾－１）,且吸光度下降,１６５０和１５４０ｃｍ＾－１处的蛋白质特征峰的吸光度也下降,而６２０ｃｍ＾－１处峰的吸光度随ＺｎＳＯ４浓度的升高显著增大。因此羟基在结合Ｚｎ＾２＋时起重要作用,结合ＺｎＳＯ４后细胞壁的结构发生了变化,结合ＺｎＳＯ４时物理吸附与化学吸附共同起作用。     

锆(Ⅳ)-桑色素-曲拉通显色反应的研究与应用

本文提出在曲拉通Ｘ－１００存在下,以桑色素为显色剂吸光光度法测定痕量锆的新方法。在「Ｈ＾＋」＝０．５－２．０ｍｏＬ的ＨＣｌ介质中形成三元配合物,其最大吸收波长为λｍａｘ＝４３０ｎｍ,摩尔吸光系数ε４３０＝９．８×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,锆量在０－１５μｇ／２５ｍＬ范围内遵守比耳定律,该方法简捷、准确,应用于铝合金中痕量锆的测定,共存离子不干扰,测定令人满意。     

Fe-CAS-NH4F-OP体系高灵敏度分光光度法测定二氧化硅中微量铁

在ＨＡｃ－ＮＨ４Ａｃ缓冲介质中,当有ＮＨ４Ｆ和乳化剂ＯＰ存在时,Ｆｅ与ＣＡＳ形成络合比为１：３的有色络合物,其最大吸收波长位于６５４．０ｎｍ,表观摩尔吸光系数为１．１８×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,１－２０μｇ Ｆｅ／５０ｍＬ线性关系良好。该法用于二氧化硅中铁的测定,结果令人满意。     

束—气条件下He（2^3S）＋CH2Cl2碰撞传能反应的动力学研究

本文在束－气条件下研究了亚稳态原子Ｈｅ（２＾３Ｓ）与ＣＨ２Ｃｌ２间的传能反应，测得了由该反应产生的ＣＨ（Ａ＾２△－Ｘ＾２П），ＣＨ（Ｂ＾２∑＾－Ｘ＾２П）ＣＨ（Ｃ＾２∑＾＋－Ｘ＾２П）和Ｈ原子（Ｂａｌｍｅｒ系）的化学发光光谱。通过对ＣＨ（Ａ，Ｂ）的光谱进行计算机模拟，推测出初手的ＣＨ（Ａ＾２△，ｖ＾１＝０－２）态振动分布为Ｎｏ：Ｎ１：Ｎ２＝１００：４０±５：１９±２，ＣＨ（Ａ＾２△，ｖ＾１＝０－０     

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     

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.