在岛津ICPQ-1000光谱仪上使用HG-3B型氢化物发生器

本文用岛津ＩＣＰＱ－１０００型光谱仪,并且使用了ＨＧ－３Ｂ氢化物发生器,这种发生器利用ＩＣＰ载气的压力产生的负压,自动吸入试样和ＮａＢＨ４溶液并发生氢化反应,生成的气态氢化物进入ＩＣＰ火炬并被激发。使用这种氢化物发生器同时测定了Ａｓ,Ｓｂ,Ｓｅ,Ｂｉ等４种元素,其检出限与常规气动喷雾器在比较至少降低了一个数量级。     

连续流动氢化物发生-原子吸收光谱法测定螺旋藻中痕量硒

将被测试液、氢化元素－ＮａＯＨ－ＮａＢＨ４溶液及ＨＣｌ溶液用三道蠕动泵在相同速率下，提取送入Ｔ型动态反应器，生成的气态氢化物由氩气载入等离子气中，测量谱线强度，该方法不需分离，直接测定，灵敏度高，干扰少的特点，是测定痕量硒的一种有效分析手段，方法下限可达０．０１７μｇ·ｇ－１，样品回收率为９８．８９％～１０１．２０％，结果令人满意。     

ICP／AES操作条件及氢化物发生条件对As、Se和Ge光谱信号影响的研究

本文较系统地研究了ＩＣＰ／ＡＥＳ操作条件及酸介质。ＮａＢＨ４溶液浓度对Ａｓ、Ｓｅ和Ｇｅ谱线强度以及信背比的影响，讨论了这些元素的最佳检测条件，考察了一些共存元素对氢化物光谱信号的影响，观察到Ａｓ、Ｓｅ和Ｇｅ氢化物发生中Ｇｅ的光谱信号的一些特殊行为，及Ｃｕ对Ｇｅ的氢化物光谱信号的增强。     

从碱性溶液中发生氢化物的原子荧光／原子吸收光谱法测定Te~（4＋）及Te~（6＋）

在０．３ｍｏｌ／ＬＮａＯＨ介质中，Ｔｅ（Ⅵ）和Ｔｅ（Ⅳ）都可与ＫＢＨ４作用，生成氢化物。在酸性介质中，只有Ｔｅ（Ⅳ）与ＫＢＨ４反应生成氢化物。利用这个事实测定不同价态碲的含量，方法快速、正确。用原子荧光法测定的检出限（３σ）为０．１ｎｇ／ｍｌ。可用于水样中不同价态碲的分析。     

连续氢化法电感耦合等离子体发射光谱同时测定生物样品…

本文叙述用氢化法电感耦合等离子体发射光谱同时测定生物样品中痕量硒，砷，锡，锑的方法。比较了浓度为２．８８ｍｏｌ／Ｌ，４．８ｍｏｌ／Ｌ和６．０ｍｏｌ／Ｌ的ＨＣｌ对Ｓｅ，Ａｓ，Ｓｎ，Ｓｂ，Ｈｇ和Ｇｅ谱线强度的影响，也比较了ＮａＢＨ４溶液中ＶＣ对测定Ｓｅ，Ａｓ，Ｓｂ，Ｓｎ，Ｈｇ和Ｇｅ的影响。在４．８ｍｏｌ／Ｌ ＨＣｌ浓度下，在１％ＮａＢＨ４溶液中加０．５％ＶＣ，ＨＹ－ＩＣＰ－ＡＥＳ的检出限是：Ｓｅ ０．     

新型激光介质NaS X^2П,A^2∑^＋,B^2∑^—,C^4∑^—,D^4П态的A…

首次提出了Ｉ～Ⅵ族元素组合ＮａＳ新型激光介质构想，并采用量子化学从头计算法计算了ＮａＳ的Ｘ＾２П，Ａ＾２∑＾＋，Ｂ＾２∑＾－，Ｃ＾４∑＾－，Ｄ＾４П态的势能曲线，证实了ＮａＳ的存在，获得了ＮａＳ各态光谱常数的理论值，比较了ＮａＳ同ＨＳ及ＮａＯ能级结构的差异。     

ICP／AES操作条件及氢化物发生条件对As,Se和Ge光谱信号影响的…

本文较系统地研究了ＩＣＰ／ＡＥＳ操作条件及酸介质。ＨａＢＨ４溶液溶度对Ａｓ，Ｓｅ和Ｇｅ谱线强度以及信背比的影响，讨论了这些元素的最佳检测条件，考察了一些共存元素对氢化物光谱信号的影响，观察到Ａｓ，Ｓｅ和Ｇｅ氢化物发生中Ｇｅ的光谱信号的一些特殊行为，及Ｃｕ对Ｇｅ的氢化物光谱信号的增强。     

流动注射-氢化物-原子荧光法测定海洋生物样品中的铅

铁氰化钾直接溶解于硼氢化钾碱性溶液中 ,与盐酸作介质的分析溶液混合进行氢化反应发生铅烷 ,氢化物发生 -原子荧光法测定海洋生物样品中的铅。对各种分析条件进行了优化和探讨。方法的线性范围为 0— 80 μg/L,检出限为 0 .31 μg/L,RSD小于 5 .6 %。经标准物质的分析验证 ,结果令人满意     

SPAPT-CPB-AS光度法测定阴离子表面活性剂

在ＮａＯＨ介质中,新试剂１－（４－磺酸基苯基）－３－「４－（苯基偶氮）苯基」三氮烯（ＳＰＡＰＴ）和溴化十六烷基吡啶（ＣＰＢ）与阴离子表面活性剂（ＡＳ）发生显色反应,形成三元配合物。利用ＳＰＡＰＴ－ＣＰＢ－ＡＳ显色体系。研究了光度法有离子表面活性剂。最大吸收波长５９０ｎｍ,测定十二基苯磺酸钠（ＤＢＯＳＯ３Ｎａ）、十二烷基磺酸钠（ＤＯＳＯ３Ｎａ）、十二烷基硫酸钠（ＤＳＯ４Ｎａ）的表观摩尔吸光系数分别为     

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。     

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.     

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.     

Research on beamforming method for dual-line array with space mismatch between the two line arrays

The performance of port/starboard discrimination of dual-line array will be seriously degraded when the space between the two line arrays of the dual-line array is mismatched. The directivity function of the delay-sum and delay-subtract beamforming is deduced and the port/starboard discrimination of the delay-sum and delay-subtract beamforming is also studied both under the ideal status and the status under which the space between the two line arrays of the dual-line array is mismatched. Analysis results show the delay-subtract beamforming has better performance of port/starboard discrimination. At last, the sea trial results demonstrate the theoretical results.     

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.     

Retrieval of ultraviolet skylight radiances and O3 slant column densities from balloon-borne limb spectrometer

With a novel light-weight and absolutely calibrated ultraviolet （UV） spectrometer, UV skylight radiances and O3 slant column densities are measured by balloon-borne limb measurements in Xinjiang area, China. UV skylight radiances measured at the height of 31 km are compared with the results from Modtran in the wavelength range from 290 to 420 nm. O3 slant column densities are derived from radiance spectra in the Huggins bands （320 - 335 nm） using differential optical absorption spectroscopy method. And the parameter exhibits a good correlation with the same value simulated by radiative transfer model （Tracy）. The O3 profile simultaneously measured by an O3 sonde is used as input in Tracy calculations. The O3 sonde is launched on the same balloon.     

Design optimization of highly sensitive LSPR enhanced surface plasmon resonance biosensors with nanoholes

For breaking through the sensitivity limitation of conventional surface plasmon resonance (SPR) biosensors, novel highly sensitive SPR biosensors with Au nanoparticles and nanogratings enhancement have been proposed recently.But in practice, these structures have obvious disadvantages.In this study, a nanohole based sensitivity enhancement SPR biosensor is proposed and the influence of different structural parameters on the performance is investigated by using rigorous coupled wave analysis (RCWA).Electromagnetic field distributions around the nanohole are also given out to directly explain the performance difference for various structural parameters.The results indicate that significant sensitivity increase is associated with localized surface plasmons (LSPs) excitation mediated by nanoholes.Except to outcome the weakness of other LSP based biosensors, larger resonance angle shift, reflectance amplitude, and sharper SPR curves' width are obtained simultaneously under optimized structural parameters.     

Polymer gratings based on photopolymerization for low-order distributed feedback polymer lasers

Novel polymer distributed feedback(DFB)gratings are fabricated based on photopolymerization to reduce lasing threshold of polymer lasers.A photopolymer formulation sensitive to 355-nm ultraviolet(UV)light is proposed for the fabrication of polymer gratings and it can be used to form polymer films by spin-coating process.A very low surface-relief depth ranging from 12.5 to about 1.0 nm has been demonstrated with a refractive-index modulation of about 0.012.The experimental results indicate that such polymer gratings have promising potentials for the fabrication of low-order DFB organic semiconductor lasers.