梅州仙人草中微量元素含量的分析

采用微波消解-电感耦合等离子体-原子发射光谱法测定了梅州仙人草中K、Ca、Na、Mg、Cu、Zn、Mn、Fe共8种元素的含量.结果表明:仙人草中K、Ca、Mg、Fe等人体必需微量元素含量非常丰富.该方法的加标回收率在96.0%-106.7%之间,相对标准偏差小于3%,具有较好的准确度和精密度.     

FAAS法测定苦杏仁和甜杏仁中的13种金属元素

采用硝酸、高氯酸(V/V=4/1)常压微沸条件下消解苦杏仁和甜杏仁样品,火焰原子吸收法测定苦杏仁和甜杏仁中的金属元素:Mn、Ca、K、Mg、Na、Zn、Cu、Fe、Co、Cd、Ni、Pb、Cr的含量,研究了测定不同元素仪器的最佳工作条件、方法的准确度和精密度.结果表明:苦杏仁中Mn、Ca、K、Mg、Na、Zn、Cu、Fe、Co、Cd、Ni和Pb的含量分别为11.756,1614.167,5153.191,238.478,97.668,274.836,16.844,546.316,9.952,3.474,5.979,2.143μg·g-1Cr未检出,方法回收率(n=9)在97.32%-102.57%之间,RSD(n=9)在0.14%-2.22%之间;甜杏仁中Mn、Ca、K、Mg、Ni、Zn、Cu、Fe、Co、Cd、Ni和Pb的含量分别为6.622,1937.503,8663.824,216.956,257.546,77.961,12.483,372.183,7.990,3.666,2.268,3.214μg·g-1Cr未检出,方法回收率(n=9)在97.23%-102.43%之间,RSD(n=9)在0.47%-2.14%之间.该法快速,简单,准确度和精密度均较高,能达到分析要求.     

ICP-AES测定自制风味红枣豆浆的营养元素

通过正交试验设计实验方案,以方差分析优化实验条件制备得到了风味独特的红枣豆浆。采用ICP-AES测定自制红枣豆浆的Ca、Zn、Fe、Mn、Mg、Cu和K7种营养元素。该法简单、快速、灵敏度高,准确性好。回收率在96.9%—100.5%之间,相对标准偏差小于2.02%。实验结果表明:自制红枣豆浆中K、Ca、Mg、Fe、Zn含量较为丰富,风味独特、品质较好。     

陕北红枣中微量元素含量测定及聚类分析

采用火焰原子吸收光谱法,测定了6种红枣中6种微量元素的含量.测定结果表明,红枣中微量元素含量丰富,其含量顺序由高到低为Ca、Mg、Fe、Zn、Mn和Cu.并对6种红枣作了聚类分析,比较分析了6种红枣之间的相关性,这对于发挥红枣的药用价值具有重要意义.     

微波消解-火焰原子吸收光谱法测定2种不同来源重楼药材中的金属元素含量

采用微波消解-火焰原子吸收光谱法测定滇重楼和华重楼中Ca、Mg、K、Fe、Zn、Cu、Mn等7种金属元素的含量。结果表明,2种药材中金属元素的含量存在差异,其中滇重楼中宏量元素Ca、K、Mg,以及微量元素Cu的含量高于华重楼;而华重楼中微量元素Fe、Zn、Mn的含量高于滇重楼。实验的相关系数r≥0.9898,测定值的RSD在0.38%—1.70%之间,方法稳定可靠,其结果为进一步开发利用重楼药材资源提供了依据。     

维药“比也”中总黄酮及微量元素含量的分析

用紫外可见分光光度法测定维药"比也"(榅桲)中的总黄酮含量,并用火焰原子吸收光谱法测定了K,Na,Ca,Fe,Cu,Co,Zn,Mn,Mg等9种元素含量.测定结果表明:"比也"(榅桲)中总黄酮量为3.87%,平均回收率为97.1%,RSD值为2.6%,并含有丰富的人体必需的微量元素,其中Na,K,Ca,Mg的含量更显著.微量元素测定方法的回收率在95.2%-104.1%之间,RSD值在0.42%-2.2%之间.通过本实验为榅桲的进一步研究和综合开发利用提供了新的科学依据.     

FAAS测定昙花中的7种金属元素

采用火焰原子吸收光谱法对昙花花和茎中K、Mg、Ca、Fe、Zn、Mn、Cu 7种金属元素的含量进行分析测定。结果显示昙花含有丰富的Fe、Zn、Mn、Cu微量元素。花中钾含量高达69763.61μg.g-1,约为茎的两倍。花中Mg、Fe、Zn、Cu的含量也高于茎,而花的Ca、Mn含量明显低于茎。昙花样品的加标回收率为93.8%—104.3%,相对标准偏差RSD≤3.67%,实验结果令人满意。     

微波消解-FAAS测定萝卜和萝卜缨中的微量元素

采用HNO3消解体系程序升温微波消解制样,应用火焰原子吸收法测定萝卜和萝卜缨中的Na、K、Ca、Mg、Fe、Mn、Zn、Cu共8种微量元素的含量.结果表明:萝卜和萝卜缨中富含人体必需的Na、K、Mg、Fe、Ca等微量元素,萝卜和萝卜缨之间微量元素含量有一定差异,其中K、Mg、Cu、Fe的含量两者差异不大,Ca、Zn和Mn在萝卜缨中的含量分别是萝卜中的3.33、3.28倍和1.75倍,Na在萝卜中的含量是萝卜缨中的1.14倍.方法的加标回收率为96.2％-105.5％,相对标准偏差(RSD)≤3.57％.方法简单快速、干扰少、精密度高、环境污染少,适合常规分析.     

控温湿法消解-火焰原子吸收光谱法测定苹果果皮和果肉中的微量元素

运用控温湿法消解-原子吸收光谱法同时测定了苹果果皮和果肉中Fe、Cu、Zn、Mn、Ca、Mg、Na和K8种微量元素的含量。方法的相对标准偏差≤1.17%,回收率介于93.8%—110.0%之间。结果表明,苹果果皮和果肉中Fe、Ca、Mn、Mg、K和Zn等人体必须的生命元素含量较高,各元素的含量均有差异。本试验为苹果的进一步研究提供了新的科学依据。     

原子吸收光谱测定刺五加中金属元素的含量

用原子吸收光谱法测定了刺五加根、茎、叶中Ca、Cu、Mg、Fe、Zn、K、Mn、Na等8种矿物质元素的含量,并对其结果进行了分析比较,以此研究了这8种金属元素在刺五加体内的分布。结果显示：各元素在实验范围内,线性关系良好,加标回收率在99%—109.6%之间,相对标准偏差为0.2%—1.8%。刺五加中不同部位的这8种元素间存在显著差异,根中Ca〉Mg〉K〉Fe〉Na〉Mn〉Zn〉Cu,其叶中的含量以K为高,而且各部位均有较高的Ca、Cu、Mg、Fe、Zn、K、Mn、Na。从微量元素的角度分析,刺五加的根、茎、叶均有一定的应用价值。     

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.     

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.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.