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本文叙述了痕量铍在铝合金中的重要作用以及石墨炉原子吸收光谱法测定铝合金中痕量铍的方法研究。该方法用硝酸(1+1)溶解样品。0.10mg/mL以上的铝具有增感效应,铍在0-0.25μg/100mL的范围内具有良好线性关系。该方法操作简便、灵敏度高,特征浓度为1.05×10 ̄(-5)μg/mL/1%。相对标准偏差为1.66%,回收率在96%-102.5%。 相似文献
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石墨炉原子吸收光谱法(GFAAS)是测定微量铍的主要方法,但干扰因素很多.本文在没有背景校正和基体改进的情况下,建立了一个一次多元线性回归模型,并采用正交回归设计方法定量研究了常见阳离子钾、钠、钙、镁和铝对测量铍的干扰.结果表明,GFAAS法测定微量铍时,钾和钠对测量的影响可以忽略不计,而钙、镁和铝对测量有增敏作用,镁和铝还存在交互效应,对测量有抑制作用.离子干扰的 定量回归方程为:A=-0.0059 0.0104(Ca2 ) 0.0874(Mg2 ) 0.1077(Al3 )-0.0239(Mg2 )(Al3 ),式中(Ca2 )表示lg([Ca2 ]/[Be2 ]),以此类推. 相似文献
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铍为脆性材料,在焊接时容易使焊缝开裂。为了防止焊缝开裂,途径之一是加延展性比较好的金属或合金(如Al-Si合金或银等)作填充材料进行钎接焊。但是,铍在非真空条件下焊接,在焊缝中出现的主要缺陷是焊接气孔和缩孔。人们早已知道,纯铝在焊接或铸造时的加热过程中会吸收环境中的氢,冷却时熔体要释放氢从而形成以氢为特征的氢气孔,进而影响铝加工的质量。这表明铝及铝合金焊接形成的气孔主要是与焊接时熔体的氢含量有关。那么,在加Al-Si合金焊接铍时,产生的气孔是否也与氢含量的关系,Al-Si合金熔体随温度升高氢含量有何变化趋势,Al-Si合金中的Si对铝熔体的吸氢起何作用。 相似文献
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塞曼效应石墨炉原子吸收法测定河水中微量铍 总被引:11,自引:0,他引:11
孙昕 《光谱学与光谱分析》1999,19(4):607-609
以镧或钡盐涂覆石管,大幅度提高测定铍的灵敏度和稳定性,并用铝或钙为基体改进剂,消除干扰,方法简便,快速,回收率92.6%-105.0%,RSD〈10.24%。 相似文献
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建立电感耦合等离子体质谱法测定居住区大气中铍、镉、砷、铅等痕量元素的分析方法.通过超声浸提同时分离气溶胶样品中多种元素,对仪器工作参数进行优化,选取72Ge,115In和204T1作为测定元素的校正内标,有效克服了基体效应、接口效应和仪器漂移对测定信号产生的影响.测定元素标准曲线的相关系数均优于0.999 5,铍、镉、砷、铅各元素的测定方法检出限分别为0.022,0.020,0.018和0.130μg·L-1,方法定最限分别为0.102,0.093,0.083和0.602 ng·m-3.通过测定标准参考物质GBW(E)080212考察方法的准确性,测定值均在标准值范围内.取采样滤膜分别加入低、中、高浓度标准溶液进行测定,样品加标回收率为91.6%~109.7%,相对标准偏差介于0.7%~4.8%.该方法精密度好、准确性好,简便、快速、灵敏,适用于居住区大气中痕量元素铍、镉、砷、铅含量的测定. 相似文献
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铍是一种轻质稀有金属,其比重仅有1.85克/厘米~3,在地壳中含量约为百万分之五左右。早先铍主要用来制造铍铜合金,氧化铍陶瓷等。1916年美国首次开始了金属铍材的工业生产,由于当时应用很少,使其发展受到限制。自从本世纪四十年代铍在原子能反应堆中得到应用以后,才引起了很多学者对研究铍发生兴趣,进一步揭示了铍的许多优良的特性,促进了铍的应用日趋广泛。 相似文献
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腐蚀和沉积对偏滤器靶板寿命的影响 总被引:1,自引:1,他引:0
讨论了偏滤器铍靶在聚变堆工况下的腐蚀问题,被物理溅射和辐射增强升华等过程腐蚀了的铍原子经电离后,部分将沉积到铍靶上,分析计算的结果表明,铍靶材被腐蚀后的自沉积将大大降低铍靶的净腐蚀率,在此基础,研究了一定浓度的硼杂质的沉积对铍靶的腐蚀率的影响,结果发现,铍靶前很低浓度的硼杂质即可大大降低了铍靶的腐蚀率,并且铍靶的腐蚀率随硼杂质浓度的增加而减少,这对聚变堆的稳态运行是有利的。 相似文献
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采用干法灰化,电感耦合等离子体-原子发射光谱法(ICP-AES)测定正常大鼠胃内硫糖铝中的铝量。结果表明,最佳分析波长为396.153nm,检出限为8ng·mL^-1,各组内相对标准偏差均小于0.81%,组间相对标准偏差均小于13.4%,铝的回收率在96.0%—99.5%之间,表明ICP-AES测定大鼠胃内硫糖铝中铝的精密度、准确度良好,满足生物样品分析要求。大鼠灌服硫糖铝6h后胃内的铝基本排空,与正常胃排空时间一致,表明硫糖铝中的铝对正常胃粘膜无粘附作用。 相似文献
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Synthesis of highly ordered nanopores on a photoresist template for applications in nanofabrications
Template synthesis involves preparation of nanostructures of the desired material within the pores of a nanoporous membrane.
In this paper we report on the fabrication of a new type of template, photoresist spin-coated on a conductive glass substrate,
as an alternative to the commonly used track-etch polymeric membranes and anodic aluminium oxide. The nanopores on the photoresist
are created by photolithography using a pre-designed pattern map stored in a Focused-Ion-Beam (FIB) machine. The pores created
are highly ordered, of uniform and desired diameters of between 20–35 nm, and run the full length of the resist membrane.
Pore dimensions are tenable in the range of 10 nm to hundreds nanometres in diameter and in the range of several micrometers
in membrane thickness. We conclude that, in addition to being functionally similar to anodic alumina, the photoresist template
is simpler and safer to fabricate making it a better alternative to in-house prepared anodic alumina templates and track-etch
polymeric membranes. 相似文献
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用原子吸收法测定大气颗粒物中的金属元素 --用CA-CN型微孔滤膜采样 总被引:6,自引:1,他引:5
本文用0.22μm孔径的微孔滤膜采集大气颗粒物中的铜,铅,锌,镉,锰,铁,镍,铬,并用原子吸收分光光度计测定。 相似文献
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提出了一种能同时测定金属铝中杂质元素Cu'Mn,Mg,Zn,Cr,Ni,V,Ti,Fe,S的ICP-AES分析方法,实验考察了金属铝基体,共存元素、不同溶剂等因素驿分析元素测试结果的影响,选择了仪器最佳工作条件。结果表明,当金属铝基体的纯度为96.00%-99.90%时,分析元素的回收率在95-105.05之间。相对标准偏差RSD均小于0.5%。在金属铝进出口商品检验中已获得满意的结果。 相似文献
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By supporting specimens on a thin membrane in the spectrophone wall, photoacoustic spectroscopy can be made on objects outside the acoustic chamber. Examples are presented from spectral measurements on liquid, powdered and thin anodic film samples on a 0.04 mm thick aluminium membrane. The conditions under which the technique may become practicable are briefly discussed. 相似文献
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氧化亚氮/乙炔火焰原子吸收与火焰原子发射光谱法测定头发样中铝 总被引:6,自引:2,他引:4
本文采用N2O/C2H2FAAS和FAES两种方法同时测定正常人头发中的铝,并对测定条件、干扰物质的影响及测定结果进行了比较。实验表明,在酸性介质中,选择396.1nm发射线,不论是物质的干扰程度、还是测定的精确度、灵敏度和回收率,FAES法均优于FAAS法。其对应的RSD(n=9)分别为2.2和2.7%,检出限分别为0.07和0.25μg/mL。在1.0g头发样品中加入20.0μg铝,其回收率分 相似文献
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Fast reactions between nitromethane and aluminium nanoparticles are studied using transient spectral methods. In comparison with species produced by pure nitromethane, the emergence time for species produced by nitromethane after addition of 1 g of aluminium nanoparticles decreases by 46-58% and the emission intensity increases by 13-100%. The results demonstrate that aluminium nanoparticles have positive effect on accelerating the decomposition rate of nitromethane and that the explosion efficiency of nitromethane is greatly improved. Fast reactions carried out between nitromethane and aluminium nanoparticles in different environments (CO2, H2O and O2) reveal that O2 and an appropriate amount of H2O improve the explosion efficieney of nitrornethane, whereas CO2 has the weakest effect on improving this parameter. The investigations provide insights into the process occurring in actual systems involving propellants and fuel-air explosives. 相似文献
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K. Habib 《Optics and Lasers in Engineering》1997,28(1):37-46
In the present investigation, holographic interferometry was utilized for the first time to measure the alternating current (a.c.) impedance of aluminium samples during the initial stage of anodization processes in aqueous solution without any physical contact. The anodization process (oxidation) of the aluminium samples was carried out chemically in different sulphuric acid concentrations (0.5–3.125% H2SO4) at room temperature. In the mean time, a method of holographic interferometric was used to measure the thickness of anodization (oxide film) of the aluminium samples in aqueous solutions. Along with the holographic measurement, a mathematical model was derived in order to correlate the a.c. impedance of the aluminium samples in solutions to the thickness of the oxide film of the aluminium samples which forms due to the chemical oxidation. The thickness of the oxide film of the aluminium samples was measured by the real-time holographic interferometry. Consequently, holographic interferometry is found very useful for surface finish industries especially for monitoring the early stage of anodization processes of metals, in which the thickness of the anodized film as well as the a.c. impedance of the aluminium samples can be determined in situ. In addition, a comparison was made between the a.c. impedance values obtained from the holographic interferometry measurements and from measurements of electrochemical impedance spectroscopy. The comparison indicates that there is good agreement between the data from both techniques. 相似文献
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We have investigated the influence of aluminium substitution for iron on the magnetic properties of amorphous and nanocrystalline Fe88-x
Zr7B5Al
x
alloys (x = 0, 1, 3, 5, 7 and 9 at.%). Thermomagnetic curves show an increase of Curie and crystallization temperature of amorphous phase with the increase of the content of aluminium in the alloy. The increase of aluminium content up to 3 at.% Al does not cause the decrease of a saturation magnetization in the as-quenched sample. In addition, magnetostriction of the annealed alloys has been studied. Also, the increase of aluminium content in the alloy causes an increase of the magnetostriction constant. 相似文献