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1.
火焰原子吸收光谱法直接测定蜂蜜制品中锌 总被引:6,自引:0,他引:6
本文研究了阴离子表面活性剂十二烷基磺酸钠(SDS),阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB),非离子表面活性TritonX-100,Tween-20,Tween-80及铬天菁S(CAS),邻菲罗啉(Phen),8-羟基喹啉(Oxine),盐酸羟胺,二乙基二硫代氨基甲酸钠(DDTC)等数种试对锌的增敏作用,初探了其增敏机理和抑制干扰的机理,选用了增敏作用最强的Triton-X-100增敏剂 相似文献
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蒋淑艳 《光谱学与光谱分析》1997,17(4):120-123
本文研究了罗庆明B-磷钼杂多酸离子缔合物体系的荧光特性及测定方法,对实验条件进行了优化选择,并引入非离子表面活性剂OP对体系增敏,增稳。本法用于黑色食品中磷的测定,结果满意。 相似文献
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同步荧光法测定食品中维生素B1 总被引:7,自引:0,他引:7
本文研究了食品中维生素B1的同步荧光法测定条件,采用氯化钾-乙醇作柱层析洗脱液,碱性介质中氧化后立即调为中性,并加入表面活性剂OP对体系增稳增敏,取代丁醇萃取,经济方便,用于几种粮食样品的测定,结果满意。 相似文献
4.
SPAPT-CPB-AS光度法测定阴离子表面活性剂 总被引:7,自引:0,他引:7
在NaOH介质中,新试剂1-(4-磺酸基苯基)-3-「4-(苯基偶氮)苯基」三氮烯(SPAPT)和溴化十六烷基吡啶(CPB)与阴离子表面活性剂(AS)发生显色反应,形成三元配合物。利用SPAPT-CPB-AS显色体系。研究了光度法有离子表面活性剂。最大吸收波长590nm,测定十二基苯磺酸钠(DBOSO3Na)、十二烷基磺酸钠(DOSO3Na)、十二烷基硫酸钠(DSO4Na)的表观摩尔吸光系数分别为 相似文献
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阳离子表面活性剂与酚红的显色反应及其分析应用 总被引:15,自引:0,他引:15
黄传敬 《光谱学与光谱分析》2000,20(2):252-255
研究了阳离子表面活性剂(CSAA)溴化十六烷基三甲铵(CTAB)、溴化十六烷基吡啶(CPB)在水溶液中与溴酚红(BPR)的显色反应。发现在PH5.0~6.0范围内,CSAA单体与BPR形成离子缔合物(缔合比为3:2),可用于微是CSAA及CSAA的临界胶束浓度(CMC)的测定。本文还研究了显色2的适宜条件、分析特征,并讨论了反应机理。 相似文献
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微乳液进样火焰原子吸收光度法测定食品中的微量锰 总被引:8,自引:0,他引:8
研究了多种表面活性剂及微乳液对火焰原子吸收光谱法测定锰的增敏作用,并选择增敏作用最强的微乳液作为锰测定的增敏试剂,拟定了测定锰的新方法。 相似文献
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用自装的激光感生时间分辨荧光光谱装置,研究了Eu,Sm-二苯甲酰甲烷(DBM)体系在阳离子表面活性剂溴代十六烷基吡啶(CPB)存在下的光谱特性和荧光衰减动力学特性。给出同时测定Eu和Sm的激光感生时间分辨荧光光谱分析方法,用于高纯氧化物中痕量Eu和Sm的测定,获得了满意的结果。 相似文献
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Eu(Sm)-DBM-CPB体系的激光感生时间分辨荧光光谱的研究 总被引:1,自引:0,他引:1
用自装的激光感生时间分辨荧光光谱装置,研究了Eu、Sin-二苯甲酰甲烷(DBM)体系在阳离子表面活性剂溴代十六烷基吡啶(CPB)存在下的光谱特性和荧光衰减动力学特性。给出同时测定Eu和Sin的激光感生时间分辨荧光光谱分析方法,用于高纯氧化物中痕量Eu和Sin的测定,获得了满意的结果。 相似文献
9.
选用碳链长度相同,极性基不同的三类表面活性剂:两性(C12BE)阴离子(SDS)阳离子(DTAB)形成胶束,通过高分辨核磁共振仪及分光光度计,研究了有或无高分子化合物PVP(聚乙烯吡咯烷酮)时,三类胶束增溶苯甲醇的位置及增溶量,结果表明,PVP包缠于SDS胶束外围,并有部分高分子链嵌入胶束中,使胶束粒径扩大,不仅侃SDS长链亚甲基裂分所需的增溶量增大,而且使SDS胶束增溶苯甲醇的总量也增大,但是, 相似文献
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胶束增敏分光光度法测定高纯石英粉中微量铝 总被引:2,自引:0,他引:2
选择阳离子表面活性剂氯化十六烷基吡啶(CPC)作为铝与铬天青S(CAS)显色体系的增敏剂,利用胶束增敏分光光度法测定高纯石英粉中微量铝,方法回收率为98%-104%,相对标准偏差低于2.7%(n=6). 相似文献
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The ways of increasing detecting power of the type M nuclear emulsion gel have been investigated in these studies. There have been found conditions under which type M emulsion sensitivity increased by 15–20% without increasing fog grain background. The stability of photographic sensitivity during emulsion gel storage increased by two times. The prevention of latent image fading (by means of layer moisture content) decreased to 1.2% and increasing the detecting power of the emulsion (by means of exposure temperature) by up to 37°C). The exposure time of tritium labelled autographs has been decreased to about 20%. 相似文献
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A. A. Chlenova A. A. Moiseev M. S. Derevyanko A. V. Semirov V. N. Lepalovskij G. V. Kurlyandskaya 《Technical Physics》2018,63(1):67-72
Multilayer structures based on Fe19Ni81 films have been obtained by ion-plasma sputtering and investigated on an impedance spectroscopy apparatus equipped with a temperature unit. An increase in the magnetoimpedance ratios for the total impedance and its real part has been found for the multilayer structure (Cu/FeNi)5/Cu/(Cu/FeNi)5 upon heating from 25 to 50°C. The maximum of the giant magnetoimpedance ratio of the total impedance ΔZ/Z = 56% has been observed at a frequency of 80 MHz with a sensitivity of 18%/Oe, while the maximum of the real part ΔR/R = 170% was observed at the frequency of 10 MHz with the sensitivity of 46%/Oe. Magnetization and resistivity at the direct current have been found to depend insignificantly on the temperature and, hence, the relaxation mechanism due to the magnetoelastic anisotropy was proposed as the most probable mechanism of increasing the value and sensitivity of the magnetoimpedance effect. 相似文献
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Stefano Corradini Marco Cervino 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,97(3):354-380
A multiple scattering inversion procedure for the aerosol extinction coefficient profile retrieval and error assessment in the oxygen A-band, for passive remote sensing instruments, has been developed. The procedure has been applied to SCIAMACHY nadir simulated measurements to investigate its effectiveness in the troposphere.The inversion procedure consists of a multiple scattering Forward Model, an inversion method and a complete sensitivity and error assessment tool. The Forward Model is based on LIDORT code; the inversion method, the sensitivity study and the complete error assessment are based on Optimal Estimation. The sensitivity and error analysis has been derived to investigate the profile retrieval errors due to the uncertainty of different aerosol optical properties, molecular and surface parameters.The analysis confirms that the profile retrieval accuracy and vertical resolution are strongly dependent on the oxygen A-band spectral resolution. The moderately high SCIAMACHY spectral resolution (0.4 nm in the oxygen A-band) results in distinguishing a maximum of three aerosol layers in troposphere. The SCIAMACHY tropospheric aerosol profile retrieval is shown to be highly sensitive to aerosol optical properties as phase function and single scattering albedo. The sensitivity study reveals an improvement of information content increasing the solar zenith angle and decreasing the surface albedo. As regards the forward model, negligible errors occur as the number of streams exceeds 6. 相似文献
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关于如何提升惠斯通电桥灵敏度一直是惠斯通电桥研究的热门话题.运算放大器组装成为的差分放大电路在一定范围内可以线性放大输入电压.但是,使用运算放大器提高电桥灵敏度的方法并未被采用.本文采用LM358N型运算放大器来提高电桥两端电势差的测量精度,从而提升惠斯通电桥的灵敏度.我们使用Multisim软件对该方案进行仿真,结果表明如果将放大倍数调至20倍,那么实际误差将小于2%.经过对改进电桥进行实际测量,实验和理论结论符合得很好.采用此方法可以得到一个易操作、低成本、高灵敏度的惠斯通电桥. 相似文献
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关于如何提升惠斯通电桥灵敏度一直是惠斯通电桥研究的热门话题.运算放大器组装成为的差分放大电路在一定范围内可以线性放大输入电压.但是,使用运算放大器提高电桥灵敏度的方法并未被采用.本文采用LM358N型运算放大器来提高电桥两端电势差的测量精度,从而提升惠斯通电桥的灵敏度.我们使用Multisim软件对该方案进行仿真,结果表明如果将放大倍数调至20倍,那么实际误差将小于2%.经过对改进电桥进行实际测量,实验和理论结论符合得很好.采用此方法可以得到一个易操作、低成本、高灵敏度的惠斯通电桥. 相似文献
16.
Mi Zhong Qi-Jun Liu Han Qin Zhen Jiao Feng Zhao Hai-Lin Shang Fu-Sheng Liu Zheng-Tang Liu 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(6):115
First-principles calculations were employed to investigate the influences of pressure on methyl group, elasticity, sound velocity and sensitivity of solid nitromethane. The obtained structural parameters based on the GGA-PBE +G calculations are in good agreement with theoretical and experimental data. The rotation of methyl group appears under pressure, which influences the mechanical, thermal properties and sensitivity of solid NM. The anisotropy of elasticity, sound velocity and Debye temperature under pressure have been shown, which are related to the thermal properties of solid NM. The enhanced sensitivity with the increasing pressure has been discussed and the change of the most likely transition path is associated with methyl group. 相似文献
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In this paper, the effect of dispersion of magnesium oxide nanoparticles on viscosity of a mixture of water and ethylene glycol (50–50% vol.) was examined experimentally. Experiments were performed for various nanofluid samples at different temperatures and shear rates. Measurements revealed that the nanofluid samples with volume fractions of less than 1.5% had Newtonian behavior, while the sample with volume fraction of 3% showed non-Newtonian behavior. Results showed that the viscosity of nanofluids enhanced with increasing nanoparticles volume fraction and decreasing temperature. Results of sensitivity analysis revealed that the viscosity sensitivity of nanofluid samples to temperature at higher volume fractions is more than that of at lower volume fractions. Finally, because of the inability of the existing model to predict the viscosity of MgO/EG-water nanofluid, an experimental correlation has been proposed for predicting the viscosity of the nanofluid. 相似文献
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