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1.
石墨炉原子吸收光谱法测定血清中砷   总被引:10,自引:1,他引:9  
本文研究了石墨炉原子吸收光谱法测定血清中砷的适宜条件,比较了镍与钯对砷的基体改进作用,给出了在Triton-X-100存在下,利用钯作为基体改进剂直接测定血清中砷的方法。检出限为6.37ng.ml^-1,相对标准偏差及回收率分别为1.79%和96.8-103.2%、线性范围50-600ng.ml^-1。  相似文献   

2.
本文设计了一种简易的加热/冷凝去溶装置,并使之与流动注射(FI)-柱预富集-ICP-AES体系联接。研究了在不同情况下进样体积、去溶温度、载液流速等对分析信号强度、检出限和精密度的影响,并与非去溶体系相比较。结果指出,去溶温度为120℃时,体系的去溶效率为34.2%,进样效率为72.5%;方法的检测限比非去溶体系改善近7倍。实验结果还表明,FI-柱预富集-去溶ICP-AES体系获得了ng/ml~亚ng/ml级的检出限,可望用于超痕量组分的测定。  相似文献   

3.
本文研究了用1-亚硝基-2-萘酚为配合剂,C18键合硅胶为固相富集材料,流动注射在线固相萃取预富集火焰原子吸收测定痕量和钴的方法。该方法自动化程度高,选择性强,方法的采样速度达90h^-1时,铜和钴的订九分别达20倍和18倍,检出限分别达1.8μg/L和3μg/L。用这一方法来测定生物样品淡菜、钢样NBS-364和NBS-362等标准样品,结果与标准值相符。  相似文献   

4.
原子吸收光谱法间接测定铁矿及锌精矿中的硫   总被引:4,自引:0,他引:4  
本文研究了铬酸钡沉淀置换-原子吸收光谱法间接测定铁矿、锌精矿中硫时大量共存元素的影响,采用数学校正方法消除大量铁的干扰。建立的方法简便、快速,特征浓度为0.16μg·ml ̄-1/1%,线性浓度范围为0~40μg/ml。试样分析的结果表明准确度及精密度均符合要求。  相似文献   

5.
本文设计了一种简易的加热/冷凝去溶装置,并使之与流动注射(FI)-柱预富集-ICRP-AES)体系联接。研究了在不同情况下进样体积、去溶温度、载液流速等对分析信号强度、检出限和精密度的影响,并与非去溶体系相比较,去溶温度为120℃时,体系的去溶效率为34.2%,进样效率为72.5%;方法的检测限比非去溶体系改善近7倍。实验结果还表明,FI-柱预富集-去溶ICP-AES体系获得了ng/ml~亚ng/  相似文献   

6.
原子吸收光谱法间接测定钒的研究   总被引:3,自引:1,他引:2  
使V置换出N-亚硝基苯胲铜中的铜,原子吸收光谱法测定铜,间接测定钒,灵敏度为0.06μg/ml1%,直线范围0-8μg/ml,应用实际样品的分析,结果良好。  相似文献   

7.
碳酸锶共沉淀富集火焰原子吸收法测定微量镉   总被引:4,自引:1,他引:3  
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%。  相似文献   

8.
流动注射氢化物发生原子吸收法测定血液中硒   总被引:2,自引:0,他引:2  
采用流动注射分析与氢化物发生原子吸收相结合的方法测定了血液中痕量硒。采用HNO3-HClO4体系溶解样品,取样量少,样品处理简单,快速。本法检出限为0.06μg/L^-1(3σ),进样频率为120-150样次/小时。讨论了砷对硒测定时的干扰及其排除方法,用该法测定了300个正常人全血和75个血清样品,其硒含量范围分别为0.056-0.118μgm1^-1和0.040-0.076μgm1^-1,回收  相似文献   

9.
本文采用双柱在线离子交换预浓缩FIA-ICP系统,建立了水及土壤浸出液中痕量钼的测定方法。用内装Dowexl(Cl^-1型)阴离子交换树脂微型柱吸附待测元素,然后用洗脱剂(1.9mol/L氯化铵-0.4mol/L柠檬酸铵混合液^[5])洗脱。在采样频率为12样/小时的速度下,浓缩倍数可达50倍。样品(自来水)回收率为90-110%;在0.2μg/ml水平时,变异系数为5.3%(n=11)。  相似文献   

10.
采用一定气孔性的石墨探针直接收集大气微粒物质(APM),然后,立即采用石墨探针炉原子吸收法测定收集在探针上的APM中痕量烟。方法准确,灵敏,简便,快速。在0-50ng/ml范围内,铟的浓度与峰面积吸光度呈良好的线性关系。铟的浓度大于300ng/ml时,产生记忆效应。铟的特征量为4.8pg,检测限为21.5pg。分析标准参比材料,铟的回收率为92.4-108.4%,相对标准偏差为8.1%。  相似文献   

11.
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   

12.
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.  相似文献   

13.
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   

14.
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.  相似文献   

15.
16.
A multi-conjugate adaptive optics (MCAO) can offer a possibility of widening field of view (FOV) characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle's expressions of two deformable mirrors (DMs) MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.  相似文献   

17.
Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.  相似文献   

18.
19.
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   

20.
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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