诺氟沙星与茜素红的显色反应及应用

诺氟沙星与茜素红在水 -乙醇体系中发生显色反应 ,反应产物的 λmax=5 2 1 .5 nm,表观摩尔吸光系数是 5 .34× 1 0 3 L·mol-1·cm-1 ,建立了简易的分光光度法。相对标准偏差为 0 .6 7% (n=6 )。测定药物制剂中诺氟沙星的含量与文献方法一致 ,回收率在 95 %以上     

靛酚蓝显色法直接测定血浆氨

建立了血浆氨的靛酚蓝直接显色测定新方法,研究了介质酸度、显色时间、共存物质及抗凝剂等的影响。结果表明,以柠檬酸钠作抗凝剂,在pH 10.5～11.2的磷酸盐缓冲体系中显色强度高,干扰小。有色化合物最大吸收波长位于630 nm,表观摩尔吸光系数为2.48×104 L·mol-1·cm-1。血浆氨浓度在0～1 500 μmol·L-1范围线性关系良好(r=0.999 9),检测下限为1.7 μmol·L-1,相对标准偏差RSD为1.13%(n=11),回收率为93.6%～101.6%,平均回收率97.0％。用本法测定43例正常人和97例各型肝病患者血浆氨含量均获得满意结果。     

巯基葡聚糖凝胶分离富集微乳液增敏三甲氧基苯基荧光酮光度法测定痕量铜

研究在微乳液介质中, pH 10.40时, 铜与三甲氧基苯基荧光酮(TM-PF)显色生成稳定的1∶2配合物, 在552 nm 处摩尔吸光系数为1.46×105 L·mol-1·cm-1, 铜含量在0～0.6 μg·mL-1 范围内符合比耳定律,引入微乳液介质,显著改善了铜的显色条件,使体系灵敏度提高。采用吸附容量大,而机械性能好的巯基葡聚糖凝胶分离富集,消除了共存离子的干扰,降低了测定体系的检出限。测定了血样、尿样、水样和矿石样品中铜的测定,相对标准偏差低于4.8%,回收率为94.2%～106%。     

ICP-AES法测定人血清中的硒

采用消化法预处理血清样品 ,并用ICP AES法测定样品中的Se ,同时 ,探索Fe的存在对测定的干扰情况以及干扰的消除方法。结果表明 ,Se的检测限为 0 0 0 76μg·mL- 1 ,加标回收率为 91 6 % ,1 0次测定的RSD(n =1 0 )为 2 1 4 7% ;在样品中加入KOH ,可以大大降低Fe对Se测定的干扰。     

原子吸收光谱法测定花粉中的微量元素

采用中温灰化样品,6 mol·L-1 HNO3浸取灰化物,用LaCl3和CsCl消除相关干扰,应用标准曲线法在同一溶液中利用空气-乙炔火焰原子吸收光谱法测定花粉中Zn,Cd,Fe,Mn,Pb,Mg,Cu,K,Ca和Na共10种元素含量。结果表明,花粉含有丰富的Zn,Mg,K,Ca,Na以及Fe,Mn,Cu,有害元素Pb的含量很低,Cd未检出。以野霍香花粉为例,详细研究确定了合适的样品处理及消除干扰条件,考察了方法的准确度和精密度。在选定的条件下,花粉中各元素间相互不干扰,可在同一份制备液中进行10种元素的分别测定。方法的加标回收率在93.4%～112.0%之间,相对标准偏差在0.3%～2.6%之间(n=5),测定结果准确可靠。     

紫外光谱法同时测定卤水海产品中I和IO_3~-

样品中I-被溴水氧化成IO-3,用甲酸除去多余的溴水,在磷酸介质中IO-3与过量的I-生成I-3;样品中的IO-3在磷酸介质中直接与加入的过量I-生成I-3,I-3在350和288nm具有强吸收,且吸光度与I-3的浓度在一定的范围内具有线性关系。通过测定样品氧化前后的吸光度分别得到样品中I-和IO-3总量以及IO-3的量,差减法得到I-的量,建立了自身紫外光谱法快速方便地测定卤水和海产品中的I和IO-3。讨论了溴水、甲酸、磷酸和碘化钾的加入量以及光照、反应时间、反应温度对测定的影响,优化试剂条件是:对测定I-的体系,加入3%溴水溶液2滴,10%甲酸溶液0.5mL,20%磷酸溶液4mL,100g·L-1 KI溶液1mL;对测定IO-3的体系,加入20%磷酸溶液0.2mL,100g·L-1 KI溶液1mL。室温避光条件下反应30min测定体系吸光度。在优化条件下,I和IO-3的浓度分别在0~1.2mg·L-1与0~1.5mg·L-1的范围内符合朗伯-比尔定律。对样品空白平行测定12次,得到I-和IO-3的检出限分别是1.54和14.8μg·L-1。对0.8mg·L-1的I和IO-3平行测定12次,相对标准偏差分别是0.097%和0.067%。用建立的方法直接测定了扎布耶卤水、洪峰地下卤水中的I-和IO-3,并且采用碱式消解测定了海带、紫菜、海白菜中I-和IO-3,同时进行了样品加标回收实验,I-和IO-3回收率均在80%~120%之间,测定结果符合分析化学检测要求。     

火焰原子吸收光谱法测定中草药川东獐牙菜中的八种微量元素

用火焰原子吸收光谱法对川东獐牙菜中K, Ca, Na, Mg, Fe, Zn, Mn和Cu八种微量元素进行了分析测定。结果显示,用HNO₃-HClO₄(5∶1)混酸作消化液处理样品,精密度和回收率较好。在选定的实验条件下,川东獐牙菜各元素间相互不干扰,可在一份样品液中进行八种元素的分别测定。川东獐牙菜中含有较丰富的K,Ca和Na, 以及Mg和Zn,其含量K＞Ca＞Mg＞Na＞Zn＞Fe＞Cu＞Mn。方法的检出限均小于0.097 μg·mL-1,RSD≤2.34%(n=8),加标回收率89.32%～106.65%。     

双水相体系中镍的光谱性能及测定

本文研究了聚乙二醇 硫酸铵 锌试剂双水相体系中镍的光谱性能及测定。结果表明 ,该体系显色的最佳酸度为pH 8 5 ,络合物光谱最大吸收波长位于 6 75nm ,摩尔吸光系数ε=1 2 6× 10 4 L·mol- 1 ·cm- 1 ,Ni(Ⅱ )线性范围为 0 2～ 2 4 μg·mL 1 。Ni(Ⅱ )和锌试剂络合比为 1∶3。与一般水溶液光度法比较 ,络合物光谱最大吸收波长红移 10nm ,络合比增加 (由 1∶1到 1∶3) ,显色反应的灵敏度和稳定性提高。该方法用于铝合金中镍的测定 ,获得满意结果。     

微乳液增敏光度法测定大米中的痕量铜

研究了溴化十六烷基三甲基铵(CTMAB)和正丁醇、正庚烷、水4组分构成的微乳液对铬天青S与铜(Ⅱ)显色反应的增敏作用,建立了测定大米中痕量铜(Ⅱ)的分光光度新方法.结果表明,在pH=6.00的NaH2PO4-NaAc缓冲溶液介质中,铜(Ⅱ)与铬天青S形成蓝绿色配合物,λmax=604 nm,表观摩尔吸光系数为6.608×104 L·mol-1·cm-1,在0-1.2 mg/L范围内吸光度与Cu2 浓度呈良好的线形关系,线性回归方程为:A=-0.01475 0.39036V,相关系数为r=0.9996.应用该方法对大米中的铜进行测定,相对标准偏差RSD=2.8%,加标回收率为97%-104%.结果表明,该方法具有较高的灵敏度、准确度与精密度,适合大米中痕量铜的测定.     

ICP-AES法同时测定铬酸钾中杂质元素

应用电感耦合等离子发射光谱法(ICP-AES)同时测定K2CrO4中微量Ca,Mg,Ba,Co,Cd,Cu,Mn,Pb,Sr,Zn,Al,Fe,Ni,Ti,Si,V等杂质元素含量.通过选掸合适的分析谱线,采用基体匹配法消除了样品中基体元素的干扰.结果表明,在选定的测定条件下,方法的标准曲线线性关系良好(R2=0.998 6～1.000),实验测得16种元素的检出限在0.075～2.625 mg·kg-1之间,两次测定的加标回收率在83.7%～113.0%之间,9次测定的RSD小于9.48%.实验表明该方法快速、简便、准确、可靠,可用于实际样品分析.通过对测定结果的分析,得出K2CrO4中含有较高含量的Ca,Mg,Al,Si,不能直接用来作为离子膜法电催化合成铬酸酐的原料,必须对K2CrO4进行进一步的精制.     

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.