钐的时间分辨激光荧光光谱分析方法研究

本文利用Ｓｍ－ＴＴＡ－ＥｔＯＨ液体荧光体系，采用时间分辨激光荧光检测手段，建立了散的时间分辨光荧光分析法，该法的线性范围为０．０１～１０μｇ／ｍｌ，检出限为３．３ｎｇ／ｍｌ，０．５μｇ／ｍｌ钐标样测定的相对标准差为３．７％（ｎ＝１２），结合混合稀土中多种元素共存的特点，实验确定了装置的有关参数，用标准加入方法对实际样品进行了测定，并与其他方法测定结果进行了比较，结果满意，本法测定实际样品中钐的相对     

稀土元素荧光增强效应的研究─RE对Eu－苯甲酰三氟丙酮－溴化十六烷基三甲基铵体系的荧光增强

本文详细研究了稀土元素Ｌａ３＋、Ｇｄ３＋、Ｔｂ３＋、Ｌｕ３＋、Ｙ３＋及Ｓｃ３＋对铕苯甲酰二氟丙酮（ＢＴＡ）－阳离子表面活性剂体系的荧光增强效应。结果表明，在上述增强离子的分别存在下，体系的荧光强度分别增加１７、７５、６５、５、５５和１８倍，铕浓度在１．０×１０－１０－８．０×１０－７ｍｏｌ／Ｌ范围内与荧光强度成线性关系，最低检出限为１．０×１０－１１ｍｏｌ／Ｌ利用标准加入法测定了混合稀土氧化物中的铕，结果满意。     

铕（Ⅱ）—噻吩甲酰三氟丙酮—丙烯酸三元配合物及其聚合物发光性质研究

研究了铕（Ⅲ）与噻吩甲酰三氟丙酮（ＨＴＴＡ）、丙烯酸（ＨＡＡ）的三元配合物及与甲基丙烯酸甲酯（ＭＭＡ）成键聚合物（ＣＰＥｕ（ＴＴＡ）２ＡＡ）和掺杂聚合物（Ｅｕ（ＴＴＡ）２ＡＡ／ＰＭＭＡ）发光性质，测量了配合物中Ｅｕ＾３＋的＾５Ｄ０和＾５Ｄ１能级的荧光衰减，对其传能过程和荧光寿命进行了讨论，测量了配合物及聚合物ＴＨＦ溶液的荧光光谱，配合物的聚合有收交配体发生明显红移，且存在配体到中心离子的传能，指出     

Eu（Sm）—DBM—CPB体系的激光感生时间分辨荧光光谱的研究

用自装的激光感生时间分辨荧光光谱装置，研究了Ｅｕ，Ｓｍ－二苯甲酰甲烷（ＤＢＭ）体系在阳离子表面活性剂溴代十六烷基吡啶（ＣＰＢ）存在下的光谱特性和荧光衰减动力学特性。给出同时测定Ｅｕ和Ｓｍ的激光感生时间分辨荧光光谱分析方法，用于高纯氧化物中痕量Ｅｕ和Ｓｍ的测定，获得了满意的结果。     

Eu（Sm）－DBM－CPB体系的激光感生时间分辨荧光光谱的研究

用自装的激光感生时间分辨荧光光谱装置，研究了Ｅｕ、Ｓｉｎ－二苯甲酰甲烷（ＤＢＭ）体系在阳离子表面活性剂溴代十六烷基吡啶（ＣＰＢ）存在下的光谱特性和荧光衰减动力学特性。给出同时测定Ｅｕ和Ｓｉｎ的激光感生时间分辨荧光光谱分析方法，用于高纯氧化物中痕量Ｅｕ和Ｓｉｎ的测定，获得了满意的结果。     

二安替比林—（邻—乙氧基）苯基甲烷褪色光度法测定微量铜的研究

合成了新试剂二安替比林－（邻－乙氧基）苯基甲烷（ＤＡｏＥＭ），根据Ｃｕ＾２＋对Ｈ３ＰＯ４－Ｍｎ（Ⅱ）－Ｃｒ（Ⅵ）－ＤＡｏＥＭ显色体系的干扰褪色作用，建立了一个测定微量铜的新方法，其检出限为４×１０＾－６ｇ／Ｌ，铜离子含量在２０－１６０μｇ／Ｌ范围内与１ｇ（Ａ０／Ａ）成良好线性关系，体系稳定性和选择性良好，用于铅样中痕量铜的测定，结果满意。     

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     

DCP—直读光谱法测高纯氧化镧中的Ce,Pr,Nd和Sm

本文提出用ＤＣＰ－ＡＥＳ方法直接测定高纯Ｌａ２Ｏ３中的Ｃｅ，Ｐｒ，Ｎｄ和Ｓｍ。方法简单、快速。检出限分别为Ｃｅ，０．０１２μｇ／ｍｌ；Ｐｒ，０．０２１μｇ／ｍｌ；Ｎｄ，０．０２１μｇ／ｍｌ以及Ｓｍ，０．００９μｇ／ｍｌ。     

ICP—AES法直接测定高纯Eu2O3中14种稀土元素

建立了ＩＰＣ－ＡＥＳ测定高纯Ｅｕ２Ｏ３中１４种稀土元素的方法，用正交设计法优化仪器测量条件，实验了基体Ｅｕ２Ｏ３对被测元素的干扰和对方法测定下限的影响。１４个稀土元素的测定下限为：Ｙｂ２Ｏ３０．５μｇ．ｇ＾－１，Ｙ２Ｏ３１μｇ．ｇ＾－１，Ｄｙ２Ｏ３，Ｈｏ２Ｏ３，Ｔｍ２Ｏ３和Ｎｄ２Ｏ３５μｇ．ｇ＾－１、Ｇｄ２Ｏ３、Ｓｍ２Ｏ３、Ｅｒ２Ｏ３、Ｃｅ２Ｏ３、Ｐｒ６Ｏ１１和Ｌａ２Ｏ３１０μｇ．ｇ＾－１，Ｌｕ２     

超声雾化空气—氩ICP—AES的检出限

医用超声雾化强器改装后的ＩＣＰ－ＡＥＳ进样装置，在高频功率３．８×０．８０ｋＷ载气流量０．８０Ｌ．ｍｉｎ＾－１，观察高度１．０ｃｍ的折衷条件下，测定了２８种元素的检出限，１５种稀土元素中Ｄｙ，Ｅｕ，Ｈｏ，Ｙ和Ｙｂ的检出限低于１μｇ．Ｌ＾－１。     

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.     

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.     

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.