共沉淀富集火焰原子吸收光谱法法测定固体弃物磷石膏中痕量镉

用ＣｕＳ作捕集沉淀剂共沉淀富集分离磷石膏中痕量Ｃｄ,研究了最佳沉淀条件,对溶液共沉淀酸度,沉淀试剂用量进行了讨论。平行６次测定Ｃｄ含量为０．０４４μｇ／ｇ的磷石膏样品,相对标准偏差为７．７９％,加标回收率在８８％￣１１０％之间。     

ICP—AES法测定锌及其化合物中的杂质元素

采用样品溶解后直接测定及氢氧化钇共沉淀将锌与被测杂质元素分离后测定相结合，研究了锌及其化合物中Ａｇ，Ｃｏ，Ａｌ，Ｎｉ，Ｆｅ，Ｃｕ，Ｃｄ，Ｃｒ，Ｍｎ，Ｉｎ，Ａｓ，Ｐｂ，Ｓｎ，Ｓｂ，Ｂｉ等１５个杂质元素的ＩＣＰ－ＡＥＳ测定方法，相对标准偏差１．６－８．１％。     

萃取—火焰原子吸收法测定骨骼中的微量元素Cu,Zn,Cd和Fe

本文研究了以邻菲罗啉为金属螯合剂，高氯酸钠为配体，在一定酸度下用１，２－二氯乙烷萃取－火焰原子吸收法测定动物骨骼中微量Ｃｕ，Ｚｎ，Ｃｄ和Ｆｅ的条件，并确定了测定方法，方法简单，准确，可靠，元素的检测限分别为：Ｃｕ：０．０３８μｇ／ｍｌ，Ｚｎ：０．００４２μｇ／ｍｌ，Ｃｄ：０．００１９μｇ／ｍｌ，Ｆｅ：０．０２μｇ／ｍｌ，回收率在９２．８％～１０５％之间。     

痕量钴、镍和镉的流动注射在线共沉淀预浓集的研究及其FAAS测定

本文应用流动注射分析技术为痕量钴、镍和镉的火焰原子吸收光谱测定建立了一个有效的在线共沉淀预浓集系统。钴、镍和镉离子在弱酸性介质中与ＡＰＤＣ－Ｆｅ２＋产生共沉淀，共沉淀反应和沉淀收集在编结反应器中同时进行。用甲基异丁基甲酮溶洗沉淀在线引入火焰原子化器中进行测定。分析速度为７２样／ｍｉｎ，样品消耗量为１．１ｍｌ以及装样时间３０ｓ时，测定钴、镍和镉获得的增感系数分别为４２、３０、３３。测定含量水平分别为２０．０、１００．０和１０．０μｇ／ｌ，钴、镍和镉的相对标准偏差为２．３％、２．０％和２．４％（ｎ＝１１）。测定钴、镍和镉的检出限（３σ）分别为１．０、３．０和０．３μｇ／ｌ。对尿样标准参考物（ＧＢＷ０９１０３）中镍和镉及动物组织牛肝标准参考物（ＮＢＳ１５７７ａ）中钴的测定结果与标准值一致     

APDC共沉淀分离富集—火焰原子吸收分光光度法测定明矾中的痕量铅

本文研究了ＡＰＤＣ－Ｃｕ（Ⅱ）共沉淀分离富集，开槽管原子捕集火焰原子吸收光谱测定铅的条件，发现痕量铅在ｐＨ值为２－８条件下能被ＡＰＤＣ－Ｃｕ（Ⅱ）定量共沉淀，方法的检出限可达１．５×１０＾－２μｇ／ｍＬ。用于明矾中痕量铅的分离富集和测定，共存物质不产生干扰，样品６次平行测定的相对标准偏差〈４％。加标回收率在９８％－１０３％之间。     

碳酸锶共沉淀富集火焰原子吸收法测定微量镉

用碳酸锶作为载体共沉淀富集镉使火焰原子吸收法测定镉的灵敏度大幅度提高。特征浓度０．０４４μｇ·ｍｌ－１／１％，加标回收率９９．７５～１０４．５％，ＳＤ是０．００６，ＣＶＳ．５２％。     

电感耦合等离子体质谱法测定高纯镉中的杂质元素

采用电感耦合等离子体质谱法测定高纯镉中的杂质元素。讨论了镉基体的谱线干扰,比较了镉基体产生的多原子离子的干扰程度,该干扰按ＣｄＨ、ＣｄＯ、ＣｄＯ２ 、ＣｄＡｒ、ＣｄＯＨ和ＣｄＯＨ２ 顺序递减。研究了不同浓度镉基体对分析物信号的抑制或增强效应,镉的浓度大于０．２５ｇ·Ｌ－ １ 时,对质量数小于１００的分析物的信号强度产生抑制,而对质量数大于１５０ 的分析物的信号强度产生增强,采用８９Ｙ和２０９ Ｂｉ作内标分别克服基体的抑制和增强效应。测定了高纯镉的Ａｓ、Ｂｅ、Ｃｏ、Ｃｕ、Ｇａ、Ｇｅ、Ｍｎ、Ｍｏ、Ｐｂ、Ｎｉ、Ｓｒ、Ａｕ、Ｔｌ、Ｔｈ、Ｖ 和Ｕ 等１６ 个杂质元素,方法的检测限０．００５～０．０５２ μｇ·Ｌ－ １ ,标准加入回收率８２％ ～１０８％ 。     

ICP-AES法测定青壳鸡蛋中的13种元素

用高压消化罐消解后,ＩＣＰ－ＡＥＳ法同时测定青壳鸡蛋中Ｃａ、Ｍｇ、Ｆｅ、Ｍｎ、Ｚｎ、Ｃｕ、Ｐ、Ｉ、Ｓｅ、Ｓｂ、Ｂａ、Ｃｒ、Ｃｄ等１３种元素的含量,在优化实验条件下,ＲＳＤ为１．２４％－８．７６％,加标回收率为９３．０％－１０５．９。方法简便、可靠,结果令人满意。     

用能带理论计算清洁Ag（111）,Ag（110）和Ag（001）表面的弛豫

用一维能带理论计算了清洁Ａｇ（１１１），Ａｇ（１１０）和Ａｇ（００１）表面的弛豫。计算结果显示出，当ｄ１＝２．６４０（膨胀４．２％）和ｄ２＝２．９２０（膨胀２３．８％）〔对ｎｇ（１１１）〕；ｄ１＝１．３７５±０．００８（收缩４．８％±０．００８）［对Ａｇ（１１０）」；ｄ１＝２．０４８±０．００５（膨胀０．２４％±０．００５）［对Ａｇ（００１）〕时，理论计算的ＬＥＥＤ谱与实验非常一致。     

ICP－AES法分析水质的探讨

本文用ＩＣＰ－ＡＥＳ（电感耦合等离子体－原子发射光谱法）测定水中Ａｌ、Ｂ、Ｂａ、Ｂｅ、Ｃａ、Ｃｄ、Ｃｏ、Ｃｒ、Ｃｕ、Ｆｅ、Ｍｇ、Ｍｏ、Ｍｎ、Ｎｉ、Ｐｂ、Ｓｒ、Ｖ、Ｚｎ等１８种微量元素。方法简便、快速，只将样品简单酸化，即可测定。方法检出限为０．０００５－０．５μｇ／ｍＬ。相对标准偏差＜１８％     

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.     

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.     

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.     

A novel methodology for photometric compensation of projection display on patterned screen

We propose a novel methodology based on the projector-camera (ProCam) system to address the photometric compensation issue for the projection display on the patterned screen.The patterned screen is treated as the combination of a perfect white screen and a color modulator.The perfect white screen is used to automatically and accurately characterize the ProCam system offline using the polynomial model,and the parameters of the color modulator can be efficiently recovered by employing only two gray images based on the linear reflectance model.The experimental results show that the color artifacts of the display image can be greatly improved with this methodology,which demonstrates its feasibility and validity in the photometric compensation.