二磺基苯基荧光酮光度法测定钢中微量钨

研究了二磺基苯基荧光酮（ＤＳＰＦ）与钨的显色反应条件,体系λｍａｘ＝５３０ｎｍ,ε＝１．６２×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,钨的含量在０￣１５μｇ／２５ｍＬ内符合比耳定律,方法用于钢样中钨的测定,结果满意。     

二磺基苯基荧光酮光度法测定铝的研究和应用

研究了二磺基苯基荧光酮（ＤＳＦＦ）与铝的显色反应,在ＰＨ＝４．６ＨＡｃ－ＮａＡｃ缓部介质中,非离子型微乳液存在下,ＤＳＦＦ和Ａｌ（Ⅲ）生成２：１紫色络合物,λｍａｘ＝６１０ｎｍ,ε＝１．４３×１０＾５Ｌ·ｍｏｌ·ｃｍ＾－１。方法用于环境水样中铝的测定,结果满意。     

邻硝基苯基荧光酮光度法测定镍的研究和应用

研究了邻基苯荧光酮与镍的显色反应,在ＰＨ＝１０．８的硼砂－氢氧化钠缓冲淀粉 中,在ＣＰＢ和ＯＰ存在下,ｏ－ＮＰＦ和Ｎｉ（Ⅱ）生成３：１的蓝紫色稳定络合物λｍａｘ＝６２０ｎｍ,ε＝１．２０＊１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,符合比耳定律的范围为０－１０μｇ／２５ｍＬ。本方法适用于铝合金中微量镍及水、电镀废水中镍的测定。     

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     

PF和吐温—80分光光度法测定铝的研究与应用

本文研究了氨性缓冲溶液中，在吐温－８０－存在下，铝与苯基荧光酮的显色反应，配合物的最大吸收波长为５５６ｎｍ，表观摩尔吸光系数为１．２×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，有色配合物配合比为Ａｌ；ＰＦ＝１：２铝量在０－５μｇ／２５ｍＬ范围内符合经耳定律。方法具有较高的灵敏度、操作简便，迅速，测定水中微量铝，结果满意。     

PF—吐温—80分光光度法测定钼的方法研究

在０．０５－０．４ｍｏｌ．Ｌ＾－１盐酸溶液中，吐温－８０存在下，钼与苯基萤光酮生成橙色配合物，在该配合物的第二吸收峰测量，其表观摩尔吸光系数ε＝１．１×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，测得配合物组成比为Ｍｏ＝ＰＦ＝１：１。在２５ｍＬ溶液中含钼０－８μｇ范围时遵守比耳定律。有色配合的稳定６ｈ以上。此法用于矿石中微量钼的测定，结果令人满意。     

Na（4D）＋Na（3S）=Na（4F）＋Na（3S）碰撞能量转移截面

利用双光子吸收，将Ｎａ（３Ｓ）原子激发到４Ｄ态，测量了Ｎａ（４Ｄ）＋Ｎａ（３Ｓ）＝Ｎａ（４Ｆ）＋Ｎａ（３Ｓ）碰撞能量转移截面，因为直接由４Ｆ→３Ｄ的荧光不能探测，所以检测３Ｄ→３Ｐ级联荧光讯号。结合基态钠原子密度的测量，给出了截面值σ４Ｄ→４Ｆ－１．３×１０＾－１４±２８％（ｃｍ＾２）。     

邻羧基苯基荧光酮与碲显色反应的研究及应用

在ｐＨ＝４．５ＨＡｃ－ＮａＡｃ缓冲介质中,ＣＴＭＡＢ存在下,邻羧基苯基荧光酮（ｏ－ＣＰＦ）和Ｔｅ（Ⅳ）生成４∶１稳定络合物,λｍａｘ＝５６０ｎｍ,ε＝１．２５×１０５Ｌ·ｍｏｌ－１·ｃｍ－１。Ｔｅ（Ⅳ）含量在０—１０μｇ／２５ｍＬ内符合比耳定律,方法用于烟尘中碲的测定,结果令人满意。     

新型显色剂2-(H-酸偶氮)-4,5-二硝基苯酚测定铁(Ⅲ)

本文研究了新试剂２－（Ｈ－酸偶氮）－４,５－二硝基苯酚与铁的显色反应,在ＰＨ５．３的ＮａＡｃ－ＨＡｃ缓冲介质中,ＨＡＤＮＰ与Ｆｅ（Ⅲ）生成３：１稳定紫色配合物,λｍａｘ＝５９０ｎｍ,ε＝１．７０＊１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,铁含量在０－１．０ｍｇ／Ｌ范围内符合比耳定律,该法用于自来水样中总铁的测定,结果令人满意。     

碘分子离子对态的时间分辨谱

本文用激光脉冲多光子激发的技术获得了碘分子高激发态Ｆ＇（０＾＋ｕ）（Ｔｅ＝５１７０６．７ｃｍ＾－１）的布居，并对该态１０个荧光辐射（３１０ｎｍ带）的时间分辨谱进行了测量。采用二步三光子的非线性激发模型对荧光时间分辨谱的数据进行处理，得到了离子对态Ｆ＇（０＾＋ｕ）的３１０ｎｍ荧光带的辐射寿命。     

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.