FAAS法测定对氯基乙酰苯胺中的铁

本文建立了火焰原子吸收光谱法测定对氨基乙酰苯胺中的铁的方法。样品用酸分解或灰化处理后进行酸溶。采用氧化性空气／乙炔火焰，于２４８．３ｎｍ波长进行测定，２４种金属离子不干扰铁的测定，其特征浓度为０．０７５μｇ／ｍＬ／１％吸收，ＤＬ（３Ｓ）为０．０１４μｇ／ｍＬ，ＲＳＤ（ｎ＝１１）为０．７２％，标准回收率为９８％－１０３％。本方法与ＩＣＰ－ＡＥＳ法及分光光度法测定结果一致。     

火焰原子吸收法直接测定二乙醇胺吸收液中铁

本文建立了火焰原子吸收法直接测定二乙醇胺吸收液中铁的分析方法,该方法简单快速,无需样品预处理,国内未见类似报道。对含１．６９－１５９００μｇ／ｍＬ铁的样品进行测定,相对标准偏差为０．７１％－８．５１％（ｎ＝９）,回收率在９４．３％－１１１％之间。     

原子吸收分光光度法测定焊尘中铁,镍,锰

建立了一个焊尘中铁，镍，锰的测定方法，优化了仪器工作参数，在优化后的条件下，铁，镍，锰三个元素的灵敏度分别为０．０４μｇ／ｍＬ／１％，０．０４μｇ／ｍＬ／１％，０．０２μｇ／ｍＬ／１％。线性范围分别为铁０．１－１０μｇ／ｍＬ，镍０．０１－２μｇ／ｍＬ，锰０．０５－５μｇ／ｍＬ。该方法回收率大于９２％，用此方法成功地测定了焊尘中三元素的含量。     

氧化亚氮／乙炔火焰原子吸收与火焰原子发射光谱法测定头发样中铝

本文采用Ｎ２Ｏ／Ｃ２Ｈ２ＦＡＡＳ和ＦＡＥＳ两种方法同时测定正常人头发中的铝，并对测定条件、干扰物质的影响及测定结果进行了比较。实验表明，在酸性介质中，选择３９６．１ｎｍ发射线，不论是物质的干扰程度、还是测定的精确度、灵敏度和回收率，ＦＡＥＳ法均优于ＦＡＡＳ法。其对应的ＲＳＤ（ｎ＝９）分别为２．２和２．７％，检出限分别为０．０７和０．２５μｇ／ｍＬ。在１．０ｇ头发样品中加入２０．０μｇ铝，其回收率分     

双波长倍增差示法测定双嘧啶片中磺胺嘧啶和甲氧苄啶的含量

本论述了双波长倍增差示法同时测定了双嘧啶片中磺胺嘧啶（ＳＤ）和甲氧苄啶（ＴＭＰ）的含量，本法是基于测定标准溶液ＳＤ（８～１４）×１０＾－６ｇ／ｍＬ，ＴＭＰ（１～２）×１０＾－６ｇ／ｍＬ，和样品溶液在２４２．５ｎｍ和２２８．０ｎｍ处的吸收度。ＳＤ和ＴＭＰ的平均回收率与ＲＳＤ分别为１００．６０％，０．３３％，和９８．２７％，１．５８（ｎ＝２０）。本法简便快捷，结果满意。     

火焰原子吸收光谱法连续测定茶叶中的锌、铜和锰

本文研究了茶叶中锌、铜、锰微量金属元素的火焰原子吸收分光光度法的测定。方法简便、快速,灵敏度和精密度高,特征浓度锌为０．００９μｇ／ｍＬ／１％,铜为０．０３１μｇ／ｍＬ／１％,锰为０．０１７μｇ／ｍＬ／１％;相对标准偏差为０．９％～５．０％,回收率９２．０％～１０６．０％。     

火焰原子吸收法测定高含量硒中碲

硒化合物在电子、玻璃等工业部门用途广泛，对高含量硒中碲的测定通常是用分光光度比色法或极谱法。本文详细研究了火焰原子吸收光谱法在这领域中的应用。使用本方法不必从硒化物试样中分离碲。在０．６—１．２ｍｏｌ／ＬＨＣｌ介质中测定碲时，检出限０．０８μｇ／ｍＬ，特证浓度０．１５μｇ／ｍＬ１％，线性范围１—２０μｇ／ｍＬ。相关系数０．９９９８。     

次甲基绿－溴酸钾体系催化光度法测痕量钒（Ⅴ）的研究

本文基于在抗坏血酸存在下，痕量钒（Ⅴ）对溴酸钾氧化次甲基绿褪色的新指示反应，建立了一个催化动力学光度法测痕量钒（Ⅴ）的新方法。线性范围为０—０．１２μｇ／２５ｍＬ和０．１２—０．２０μｇ／２５ｍＬ，方法检出限为３．４×１０~（－１０）ｇ／ｍＬ。用于人发、水样中痕量钒（Ⅴ）的测定，结果满意。     

次甲基绿—溴酸钾体系催化光度法测痕量钒（V）的研究

本文基于在抗坏血酸存在下，痕量钒（Ｖ）对溴酸钾氧化次甲基绿褪色的新指示反应，建立了一个催化动力学光度法测痕量钒（Ｖ）的新方法。线性范围为０－０．１２μｇ／２５ｍＬ和０．１２－０．２０μｇ／２５ｍＬ，方法检出限为３．４×１０＾－１０ｇ／ｍＬ。用于人发、水样中痕量钒（Ｖ）的测定，结果满意。     

催化动力学光度法测定痕量铁(Ⅲ)的研究

在弱酸性介质中,利用铁（Ⅲ）对高磺酸钾氧化溴酚蓝的催化作用,建立了催化光度测定痕量铁（Ⅲ）的新方法。该方法线性范围在０－１．２μｇ／２５ｍＬ之间,检出限为３．１＊１０＾－１０ｇ．ｍＬ＾－１。测定出反应表观活化能为Ｅａ＝９８．６６ｋＪ／ｍｏｌ。此法用于水样中微量铁的测定,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.     

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.     

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.     

Theoretical analysis and simulation of conjugate heights for dual-conjugate AO system in lidar

A multi-conjugate adaptive optics （MCAO） can offer a possibility of widening field of view （FOV） characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle＇s expressions of two deformable mirrors （DMs） MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.     

Quick single-photon detector with many avalanche photo diodes working on the time division

Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.     

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.     

Improvement of four-wave mixing-based wavelength conversion efficiency in dispersion shifted fiber by 40-GHz clock pumping

40-GHz clock modulated signal as a pump to improve the efficiency of four-wave mixing (FWM)-based wavelength conversion in a 26.5-km dispersion shifted fiber (DSF) is investigated. The experimental results demonstrate that the conjugated FWM component has higher intensity with the clock pumping than that with the continuous-wave (CW) light pumping. The improvement of FWM-based wavelength conversion efficiency is negligible when the pump power is less than Brillouin threshold. But when the pump power is greater than Brillouin threshold, the improvement becomes significant and increases with the increment of pump power. The improvement can increase up to 9 dB if pump power reaches 17 dBm.     

Characterization of PolyA and PolyC mismatches by Raman spectroscopy

A.C mismatches are studied by Raman spectral characterization of PolyA, PolyC, and their equimolar complex in solution of 0.14 mol/L Na ,pH7.0.Experimental results show that A·C mismatches occur to be A/B (mainly A) conformers, and unlike Watson-Crick base pairing, this kind of mismatches is stabilized by only one hydrogen bond involving cytosine N4H2 and adenine N7.The formation of A·C complex makes the base stacking interactions much stronger, and conformation of the backbone more ordered, which leads to obvious Raman hypochromic effect with some shifts in corresponding bands.