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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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利用微波消解,空气-乙炔火焰原子吸收光谱法对蕨麻中钾、钠、钙、镁、铜、锌、铁、锰8种人体必需矿物元素进行了测定。对样品的预处理方法、仪器的测定条件、共存元素的干扰及消除进行了研究,并对各测定元素进行了加标回收率实验。结果表明,在选定的实验条件下,该法的相对标准偏差均小于2.5%(n=8),各元素加标回收率为96.5%—103.2%。 相似文献
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ICP-AES同时测定辣木叶中的6种微量元素 总被引:5,自引:0,他引:5
采用湿法、泡制法、水煮法处理样品,以ICP-AES测定辣木叶中的Ca、K、Mg、Fe、Zn、Cu6种微量元素。方法简单、快速、灵敏度高、准确性好,可同时测定多种元素。6种元素的加标回收率为98%—104%,相对标准偏差均小于3.5%。 相似文献
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原子吸收分光光度法同时测定粮谷中痕量镉和砷 总被引:2,自引:0,他引:2
本文利用干扰效应并采用模拟退火 误差反向传播人工神经网络算法辅助原子吸收分光光度法在单波长下对粮谷中痕量镉和砷的同时测定时行了研究 ,取得了满意结果。标准加入法的回收率分别为 91%~98%和 87%~ 92 % ,7次平行测定结果的相对标准偏差均小于 4%。该法快速、简单 相似文献
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The molecular aggregation and spectroscopic properties of Pyronin Y (PyY) in the suspension containing natural bentonite clay were studied using molecular absorption, steady-state and time-resolved fluorescence spectroscopy techniques. Interaction between the clay particles and the cationic dye compounds in aqueous solution resulted in significant changes in spectral properties of PyY compared to its molecular behavior in deionized water at the same concentration. These changes were due to the formation of dimer and aggregate of PyY in the clay suspension as well as the presence of the dye monomer. The H-type aggregates of PyY in the clay suspension were identified by the observation of a blue-shifted absorption band of the dye compared to that of its monomer. In spite of diluted dye concentrations, the H-aggregate of PyY in the clay suspension was formed. The intensive aggregation in the clay suspension attributed to the localized high dye concentration on the negatively charged clay surfaces. Adsorption sites of PyY on the clay particles were discussed by deconvulated absorption and excitation spectra. Fluorescence spectroscopy studies revealed that the fluorescence intensity of PyY in the clay suspension is decreased by H-aggregates drastically. Moreover, the presence of H-aggregates in the clay suspension resulted in the decrease of fluorescence lifetime and quantum yield of PyY compared to those in deionized water. 相似文献
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The suspension characteristics of water droplet in oil were investigated under ultrasonic standing waves with high-speed photography in this paper. Firstly, the suspension position of droplet was predicted by theoretical derivation. The motion trajectory of droplet was captured and a kinetic analysis was applied to characterize the suspension position of droplet. The effects of droplet size, acoustic pressure, frequency, as well as density ratio of water and oil on the suspension position of droplet were analyzed in details. It was proved that the droplet size had little effect on the suspension position at different frequencies. The suspension zone approached minimum at 39.4 kHz, and the suspension position of droplet was insensitive to acoustic pressure amplitude and density ratio at this frequency. These would be advantageous to maintain the stability of droplet banding and shorten the width of banding. In addition, it was proved that the suspension position of droplet is approximately linear with the density ratio at different frequencies. 相似文献
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利用多重光散射技术研究吡虫啉悬浮剂的物理稳定性 总被引:1,自引:0,他引:1
Turbiscan Lab稳定性分析仪利用多重光散射技术,能够准确测量乳状液、悬浮液等沉淀层、浮油层或澄清层厚度以及粒子平均粒径随时间的变化情况,定性定量分析体系不稳定性发生的机理和速率。本文利用Turbiscan Lab稳定性分析仪测定了不同萘磺酸盐分散剂GY-D10,NNO,Morwet D-425,TERSPERSE 2425制备的350 g·L-1吡虫啉悬浮剂及其悬浮液背散射光强度随时间的变化情况以及颗粒平均粒径的聚结增大速率,同时利用激光粒度分析仪测定加速试验前后颗粒平均粒径的变化情况,结果表明:添加分散剂GY-D10,用量为4 Wt%时悬浮液的稳定性最好,对应的吡虫啉悬浮剂的稳定性也最好。 相似文献
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《Current Applied Physics》2015,15(8):857-863
Au–Ag bimetallic nanochains were prepared using pulsed laser ablation in liquid medium. Synthesis was performed by ablating silver target in a gold colloidal suspension. The plasmon characteristics of the nanostructures are found to be sensitive to ablation duration. AFM and TEM images indicate that almost all nanoparticles, both Au and Ag in the suspension participate in the growth process. An attempt was also made to realize plasmon hybridization by reducing the volume of the suspension by simple evaporation. The nanochains were tested for application as SERS substrates by using crystal violet as probe molecules. 相似文献
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A method for fabricating well-dispersed nanowire suspension has been demonstrated in the paper. Thin gold nanowires were prepared by template synthesis, and then functionalized with sulphonate group-terminated thiols before suspended in different solvents. The degree of aggregation of the obtained suspension was evaluated with transmission electron microscopy (TEM) and UV-vis spectroscopy. It was found that the degree of aggregation was predominated by the solvents, and the best degree of dispersion was obtained when isopropyl alcohol (IPA) was used as the solvent. The gold nanowires from the suspension can be selectively assembled onto chemically patterned substrates. This well-dispersed nanowire suspension is potentially useful for fabricating novel nanodevices. 相似文献
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悬浮液进样-火焰原子吸收光谱法测定面粉中的钙和镁 总被引:16,自引:0,他引:16
将悬浮液进样技术应用于火焰原子吸收光谱法,成功地测定了面粉中的钙,镁。将面粉悬浮于含有邻葳二甲酸二丁酯的琼脂胶体中而制成悬浮液。对悬浮剂的选择及化学干扰的消除进行了考查。 相似文献
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While driving off-road vehicles, operators are exposed to whole-body vibration acting in the fore-and-aft direction. Seat manufacturers supply products equipped with fore-and-aft suspension but only a few studies report on their performance. This work proposes a computational approach to design fore-and-aft suspensions for wheel loader seats. Field tests were conducted in a quarry to analyse the nature of vibration to which the driver was exposed. Typical input signals were recorded to be reproduced in the laboratory. Technical specifications are defined for the suspension. In order to evaluate the suspension vibration attenuation performance, a model of a sitting human body was developed and coupled to a seat model. The seat model combines the models of each suspension component. A linear two-degree-of-freedom model is used to describe the dynamic behaviour of the sitting driver. Model parameters are identified by fitting the computed apparent mass frequency response functions to the measured values. Model extensions are proposed to investigate postural effects involving variations in hands and feet positions and interaction of the driver's back with the backrest. Suspension design parameters are firstly optimized by computing the seat/man model response to sinusoidal acceleration. Four criteria including transmissibility, interaction force between the driver's back and the backrest and relative maximal displacement of the suspension are computed. A new suspension design with optimized features is proposed. Its performance is checked from calculations of the response of the seat/man model subjected to acceleration measured on the wheel loader during real work conditions. On the basis of the computed values of the SEAT factors, it is found possible to design a suspension that would increase the attenuation provided by the seat by a factor of two. 相似文献