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流动注射 -氢化物发生 - ICP- AES检测小麦粉样品中痕量的砷 ,正交设计试验找出仪器测定的最佳工作条件 ,并对影响测定的主要参数和砷的氢化物产生条件进行了研究。该方法对小麦粉中砷的检测结果令人满意 ,砷检出限为 0 .15 μg/ L,相对标准偏差 <2 .5 %。 相似文献
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微波消解-氢化物发生原子荧光光谱法测定复合疏松剂中的砷 总被引:2,自引:0,他引:2
建立了测定复合疏松剂中砷的微波消解-氢化物发生原子荧光光谱方法,试验了微波消解复合疏松剂样品的适宜条件,试验了测定中酸介质和还原剂用量对砷信号的影响,通过实验确定了仪器的最佳工作条件,讨论了复合疏松剂中常见元素对测定的干扰情况.本方法中,砷的荧光强度与浓度在0-100μg/L范围内呈线性关系,相关系数为0.9992,方法检出限为0.22μg/L,回收率为89%-115%,方法相对标准偏差小于5%.该方法准确、快速,应用于复合疏松剂中砷的测定,获得满意结果. 相似文献
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利用硝酸-高氯酸消解处理试样,建立了原子荧光光谱法同时测定污泥中砷和汞的方法.并对消解体系、负高压、灯电流、载气流量、屏蔽气流量、硼氢化钠浓度等作了研究并予以优化.方法的线性范围:砷0.0-60.0ng/mL、汞0.0-6.0ng/mL,相关系数r≥0.9998;砷和汞的检出限均为0.03ng/mL;砷、汞相对标准偏差均不大于2%,试样加标回收率砷91.0%-104.0%和汞90.0%-96.0%.该方法操作简便、快速、灵敏度高,完全适用于污泥试样的检测. 相似文献
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高压消解-双道氢化物发生-原子荧光光谱法同时测定苦丁茶原植物中的砷和汞 总被引:1,自引:0,他引:1
采用HNO3/H2SO4预消解、HNO3/H2O2高压消解,硫脲-抗坏血酸预还原等手段,建立了高压消解-双道氢化物发生-原子荧光光谱同时测定苦丁茶原植物中砷和汞含量的分析方法。讨论并优化了分析测定条件,结果表明,砷和汞的线性范围分别为1.0×10-3—11.0×10-3mg.L-1和1.0×10-4—10.0×10-4mg.L-1,相关系数r分别为0.9986、0.9970,检出限分别是4.73×10-5mg.L-1和8.70×10-6mg.L-1;相对标准偏差(n=6)砷不大于4.25%,汞不大于4.92%。应用于5种苦丁茶原植物砷和汞含量的测定,该方法操作性强、用时短、灵敏度高。 相似文献
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研究了AFS-930型双道原子荧光光度计同时测定农产品中砷和硒的方法.该法快速,简便,准确,砷回收率为91.9%-99.6%,硒回收率为93.5%-103.8%,相对标准偏差(RSD)砷小于2%,硒小于1%,检出限分别为0.035μg/L和0.038μg/L. 相似文献
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一次性消解-原子吸收光谱法、原子荧光光谱法检测水产品中铅、镉、铜、锌和砷 总被引:3,自引:0,他引:3
采用湿法消解一次性处理水产品,塞曼石墨炉原子吸收光谱法测定铅、镉、铜,火焰原子吸收光谱法测定锌、氢化物发生-原子荧光光谱法测定砷.该方法简便、快速,通过优化前处理和上机条件,在最优条件下进行测试,铅、镉、铜、锌、砷的检出限分别为0.012、0.001、0.008、0.089、0.009mg/kg,回收率范围为87.6%-110%,相对标准偏差为3.9%-6.8%.通过测定有证标准物质,证明该方法具有很好的准确度. 相似文献
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Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide 总被引:1,自引:0,他引:1
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. 相似文献
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S. G. Nedel’ko M. A. Krysyuk A. L. Apanasenko L. N. Lymarenko Z. T. Moroz 《Journal of Applied Spectroscopy》1997,64(1):55-61
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. 相似文献
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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. 相似文献
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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. 相似文献
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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. 相似文献
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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. 相似文献
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Yepeng Guan 《中国光学快报(英文版)》2008,6(6)
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. 相似文献
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Byeong Ha Lee Young-Jae Kim Youngjoo Chung Won-Taek Han Un-Chul Paek 《Fiber and Integrated Optics》2001,20(5):443-455
A novel method based on fiber gratings for measuring the effective indices of fiber modes is proposed. The effective index difference between the core mode and a cladding mode was obtained by analyzing the interference fringe of a pair of cascaded long-period fiber gratings. In order to extract the core mode index from the measured index difference, an index matching oil immersion method is proposed. By analyzing the interaction between the cladding mode and the oil applied on the cladding surface, the mode order and the effective index of the involved cladding mode might be calculated. Experimental results about the interference fringe shifts induced by the oil index and the oil-applied length are also presented. 相似文献
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Nonlinear optical pulse compression of picosecond pulses typically requires long lengths of optical fiber and multiple components. Periodic structures, such as fiber Bragg gratings, are highly dispersive at wavelengths outside of the photonic bandgap. This implies that such gratings can be used as very short all-fiber compressors. In this paper a number of such compression schemes are reviewed involving uniform and nonuniform fiber Bragg gratings, relying on both soliton and nonsoliton compression principles. Experimental results supporting the corresponding underlying theory are also presented. Finally, an extension of one of the compression schemes is shown, which allows the generation of adjustable high-repetition rate soliton trains. 相似文献