火焰原子吸引光谱法测定鱼腥草、西洋参和茯苓中的铜含量

用硝酸-高氯酸混合酸(4:1)消化鱼腥草、西洋参和茯苓,在波长324.8nm处,利用火焰原子吸收光谱法测定鱼腥草、西洋参和茯苓中铜的含量.线性回归方程为A=0.1708C 0.0004,相关系数r=0.9997,线性范围为0-5μg/ML,检出限为0.0035μg/ML,测定结果的相对标准偏差为0.09%,加标回收率为98.0%-104.2%.     

食品中汞含量的直接进样测定

建立直接进样测定食品中汞含量的无损分析方法。在最佳测定条件下的线性回归方程为y=0.0261x+0.0006,线性范围为0.5—10.0μg/mL,相关系数为r=0.9999,检出限为0.0044μg/mL,加标回收率为98.7%—104.3%,RSD为0.38%。本方法具有简便、快速、灵敏度高等优点,用于食品中汞含量测定,结果满意。     

裸玻碳电极直接电化学发光测定诺氟沙星含量

基于诺氟沙星能够显著增强过硫酸根的电化学发光信号,建立了一种灵敏、简便而且价廉的测定诺氟沙星含量的新方法。在最佳实验条件下,诺氟沙星浓度在0.141—6.33μg/mL范围内,与电化学发光信号强度呈良好的线性关系,线性回归方程为IECL=116.4+73.5CNFLX(μg/mL),r=0.9968,检出限为0.039μg/mL(S/N=3)。对4.22μg/mL的诺氟沙星平行测定11次,RSD为1.3%,表明该方法具有良好的重现性,并成功地应用于人尿样中诺氟沙星含量的测定。     

水杨醛缩4-氨基安替比林分光光度法测定痕量铜

合成了席夫碱水杨醛缩4-氨基安替比林(SALAAP),据此建立起一种新的测定痕量铜的直接分光光度法。线性回归方程为A=0.0462+0.1885[Cu2+](μg/mL),相关系数r=0.9990。线性范围为0.20—2.5μg/mL,检出限为4.6×10-8g/mL。本法已成功用于江水中铜含量的测定。     

高效液相梯度洗脱法测定银黄含片中黄芩苷、绿原酸和芦丁

建立了反相高效液相色谱法同时测定银黄含片中的黄芩苷、绿原酸和芦丁。采用HypersilODSC18柱(200mm×4.6mm,粒径5μm),流动相A:甲醇-水-乙酸(10∶88∶2)和流动相B:甲醇-水-乙酸(88∶10∶2),梯度洗脱程序0min(A∶B/97∶3)-10min(A∶B/73∶27)-25min(A∶B/20∶80)-36min(A∶B/20∶80);流速1.0mL/min;检测波长为327nm和280nm;柱温25℃。黄芩苷线性范围为0.051—0.512μg/mL,r=0.9990,样品的平均加标回收率为98.23%,(RSD为2.13%);绿原酸线性范围为0.059—0.592μg/mL,r=0.9996,样品的平均加标回收率为97.61%,(RSD为2.13%);芦丁线性范围为0.087—0.868μg/mL,r=0.999,样品的平均加标回收率为98.56%,(RSD为1.13%),该方法专属性强,结果稳定,重现性好,能有效地控制药品的主成分含量,具有较强的实用价值。     

RP-HPLC同时测定辛芷提取物中的木兰脂素和欧前胡素

建立了RP-HPLC同时测定辛芷提取物中木兰脂素和欧前胡素的含量。取辛芷鼻提取物,用甲醇溶解,0.45μm微孔滤膜过滤,取续滤液进样检测。采用Hedera C8分析柱(4.6mm×250mm,5μm),流动相为乙腈-水(50∶50,V/V),流速1mL/min,柱温25℃,检测波长为278nm。木兰脂素、欧前胡素的线性范围分别为21.88—350.00μg/mL(r=0.9996,n=5)、1.25—20.00μg/mL(r=0.9997,n=5),平均回收率分别为103.56%、102.79%。该法简便、快速,结果准确可靠。     

苯酚红褪色分光光度法测定小麦粉中的痕量溴酸钾

对苯酚红褪色分光光度法测定小麦粉中痕量溴酸钾进行了研究。实验考察了各种因素如酸度、苯酚红的浓度和用量、反应时间和温度等对测定的影响。结果表明,在最优化的实验条件下(最大吸收波长为504nm,0.5mol/L盐酸,1.00mL 1.00×10-4mol/L苯酚红,85℃水浴条件下加热10min),溴酸钾在0—0.45μg/mL范围内符合比耳定律,线性回归方程为ΔA=0.6094C-0.0013(C:μg/mL,相关系数r=0.9991),摩尔吸光系数ε=3.6×106L.mol-1.cm-1,检出限为0.01μg/g(取样量5g)。将该法用于小麦粉中痕量溴酸钾的测定,样品加标回收率在93%—103%,相对标准偏差RSD<5%,结果满意。     

HPLC同时测定清胃黄连丸中的4种有效成分

建立同时测定清胃黄连丸中栀子苷、黄芩苷、小檗碱和巴马汀含量的HPLC方法。结果表明,栀子苷、黄芩苷、小檗碱和巴马汀分别在2.07—66.2μg/mL（r=0.9997）、2.72—86.9μg/mL（r=0.9998）、2.23—71.3μg/mL（r=0.9998）、2.13—68.1μg/mL（r=0.9998）范围内与峰面积呈良好的线性关系;平均回收率分别为103.2%（RSD=3.27%）、106.7%（RSD=2.46%）、103.5%（RSD=2.13%）、95.7%（RSD=2.68%）。该方法简便可行、重现性好、能更好的控制清胃黄连丸的质量。     

胶束电泳法测定五味子中的3种有效成分

建立了基于一种快速、高效分离与测定五味子中五味子甲素、五味子乙素和五味子酯甲含量的胶束毛细管电泳-紫外检测分析新方法。以毛细管(70cm×50μm i.d×375μm o.d)为分离通道,在最佳电泳介质(30mmol/L SDS,pH=7.2,20mmol/L磷酸盐缓冲溶液)中,当分离电压为21kV时,3种待测物质在11min内达到基线分离。在254nm波长处,五味子甲素、五味子乙素和五味子酯甲的线性响应范围分别为5.0—150.0μg/mL、1.0—100.0μg/mL和1.5—150.0μg/mL;检出限分别为1.0、0.22μg/mL和0.4μg/mL。该方法具有良好的重现性,以100.0μg/mL的五味子甲素、五味子乙素和五味子酯甲测定其保留时间和峰高相对标准偏差(RSD)(n=7)均小于2.98%。本方法用于中药五味子中五味子甲素、五味子乙素和五味子酯甲的含量测定,结果令人满意。     

荧光法直接测定环境水中邻羟基苯甲酸和苯酚混合物的含量

本文研究了用荧光分光光度法测定环境水中苯酚和邻羟基苯甲酸的含量,在pH＞11时直接测定邻羟基苯甲酸的含量,波长为λex/λem=289/338nm,检出限为3.4ng/mL,线性范围0-6.0μg/mL.在pH=6,波长为λex/λem=270/297nm测得苯酚含量,检出限为4.0ng/mL,线性范围在0-0.85μg/mL,回收率为98%-101%,结果满意.     

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.     

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.     

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.     

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.