X射线荧光光谱法测定萤石中CaF_2、CaCO_3、S、Fe及SiO_2

X射线荧光光谱法分析是目前快速分析方法之一,精密度受基体效应、均匀性、元素间干扰等影响。采用粉末压片法制备样品,用X射线荧光光谱法直接测定F、Ca元素,得出CaF_2及CaCO_3含量,并同时分析萤石中S、Fe、SiO_2的含量。精密度实验表明,待测元素的相对标准偏差均低于0.66%(RSD,n=10),能满足萤石中各元素的检测要求。     

X射线荧光光谱法测定萤石中氟化钙

采用X射线荧光光谱仪可以快速准确测定萤石中总钙的含量.但测定其中氟化钙含量时,一方面,由于样品中碳酸钙计入钙量,从而造成氟化钙测定结果准确性较差.另一方面,铜、锌等金属元素在熔融制样时对铂金坩埚腐蚀较大,因此需要进行酸处理除去碳酸钙及铜、锌等金属元素.然而,样品经过酸处理后,质量会发生变化,造成熔剂与样品的比例不一致,从而影响测定结果.对样品前处理条件、XRF分析中熔片和仪器工作条件等进行了优化,建立了熔融制样、X射线荧光光谱法（XRF）准确测定萤石中氟化钙含量的方法.方法干扰少,具有良好的准确度和精密度,操作简单,提高了分析效率.     

X射线荧光光谱法测定不同类型分子筛中氧化物的含量

分子筛是催化裂化催化剂中重要的活性组分.产品中Na2O、Al2O3、SiO2、RE2O3,等元素氧化物的含量将直接影响分子筛的质量和性能.通过对方法准确度和精密度的考察,表明X射线荧光光谱法(XRF)测定分子筛中重要元素氧化物的含量,准确度高,重复性好,是一种高效、快速、能有效指导企业生产的分析方法.     

X射线荧光光谱法测定哈氏C-276合金中10种元素

采用X射线荧光光谱法,可实现同时测定C-276合金中Si,Mn,P,Cr,Fe,Mo,W,V,Co,Cu,方法简便快速,便于生产过程控制和产品分析。采用成分相近的17种标准物质建立工作曲线,优化了测量条件并进行谱线重叠校正和元素间的吸收和增强效应的校正,各元素含量与测量强度均能呈现良好的线性关系。用于C-276合金中各元素的测定,具有良好的精密度,测定值与分光光度法、容量法、重量法等标准方法测定结果显示较好的一致性。为建立X射线荧光光谱法测定镍基合金成分提供了思路,为研究X射线荧光光谱分析镍基合金的干扰提供事实依据。     

粉末压片-X射线荧光光谱法与红外吸收光谱法联合测定萤石中各组分

采用粉末直接压片法,用X-射线荧光光谱法[1]测得萤石中Ca总量,Fe2O3,P,SiO2,K2O的含量,再用红外吸收光谱法测得样品中碳含量,换算得到CaCO3中的钙含量,进一步求得萤石中CaF2含量。此方法简便、准确。用9个标准物质制定了工作曲线,并进行了自测,另用该系列中5号样品(GBW07254)进行准确度和精密度测试,结果令人满意。     

X射线荧光光谱法测定铝合金及纯铝中痕量元素

根据X射线荧光光谱法分析样品形状要求,按照待测物料形状,适合于X射线荧光光谱测量的棒状类样品用车床车割,块、片状类样品用锯、锉刀处理,屑类样品首先用液压机压成片状,再用锉刀处理成适合于X射线荧光光谱分析的待测样品.测试了铝合金和纯铝中铁、硅、铜、镓、镁、锰、锌、钛和铬的含量,对于测量不灵敏的镁,每次测试带全套标样,峰值计量,单独为组测量可保障其准确度.基体单纯、固定的样品,测量痕量元素含量时峰值强度计量优于扣除背景的净强度计量,可避免背景测量误差,测量结果与直读光谱法相符.9项元素的精密度均优于3%.     

波长色散X射线荧光光谱仪和多晶X射线衍射仪联用技术鉴定进口铜矿和含铜物料

首次研究进口可利用含铜物料与进口铜矿属性的不同特性并建立了鉴定方法,采用X射线荧光光谱法和X射线衍射光谱法联用技术建立铜矿和含铜物料属性的鉴别方法。通过X射线荧光光谱法对铜矿和含铜物料中元素进行定性半定量分析,再用X射线衍射光谱法对铜矿和含铜物料的特征谱峰进行扫描,与X射线衍射仪中标准卡片比对分析,能够确定铜矿和含铜物料的物相组成。结果显示,X射线荧光光谱法测定的铜矿和含铜物料的共同特点是铜的含量较高,达到冶炼铜对原料的要求;硅、铁、钠、钙和镁元素都能够检出;差异性在铅和锌元素在含铜物料中较高,在铜矿石中基本未检出;用X射线荧光光谱法检测出的金属元素,通过X射线衍射仪扫描后与标准图片比对,各元素以不同的形式存在于含铜物料中,且有规律可循。     

X射线荧光光谱法快速测定铅铋合金中的铅、铋、金、银、铜、砷、锑、锡和碲

建立快速测定铅铋合金中铅、铋、金、银、铜、砷、锑、锡、碲含量的X射线荧光光谱法。采用自制的铅铋合金样品作为标准样品,用台式车床制样,用X射线荧光光谱法快速测定铅铋合金中各元素含量,并用α理论系数法和经验系数法相结合对基体效应进行校正。各组分校准曲线的相关系数均大于0.998,检出限为5.54～101μg/g,测定结果的相对标准偏差为0.06%～7.73%(n=9)。用该方法对3个铅铋合金样品进行分析,测定结果与参考值吻合,相对误差小于8.33%。该方法简便快捷,结果准确,能满足铅铋合金中各元素检测要求,对炉前分析具有很强的实用价值。     

X射线荧光光谱法测定聚乙烯树脂中微量铬

X射线荧光光谱法应用于各种材料中元素测定,其含量分析范围为1×10-3%～100%,具有测定元素范围广、测定精度高、分析速度快、非破坏性分析等特点.     

X射线荧光光谱法测定螺旋藻中23种微量元素

采用粉末压片制样,实现了螺旋藻中磷、硫、氯、溴、硅、钠、钾、镁、钙、钛、钒、铬、铁等23种微量元素的X射线荧光光谱法测定。研究了粉末压片法制样时研磨时间和颗粒度对荧光响应信号的影响,采用GBW07603,GBW10025等国家一级标准物质绘制校准曲线,经标准物质验证,分析结果与标样吻合。对样品中23种元素所测值做精密度考察,同一样片重复测定10次时各元素含量的相对标准偏差在0.7%~10%范围内;10个样片分别测试时各元素含量的相对标准偏差在0.1%~6.6%范围内。通过与电感耦合等离子体质谱法比对,所得结果基本一致。研究表明,X射线荧光光谱法可以实现螺旋藻中一系列微量元素的便捷、准确检测。     

Trace Element Analysis of USGS Standards AGV2, BCR2, BHVO2, DTS2 and GSP2 by INAA

Five second generation USGS standards AGV2, BCR2, BHVO2, DTS2 and GSP2 were analyzed for trace elements by instrumental neutron activation analysis. Abundances of the rare earth elements La, Ce, Nd, Sm, Eu, Tb, Yb, Lu and eight other elements Co, Cr, Cs, Hf, Na, Sc, Ta and Th were determined in all samples, except for DTS2 which was analyzed only for Co, Cr, Na and Sc. Experimental precision and accuracy were evaluated. In general abundances of trace elements in this new generation of USGS standards are similar to the earlier standards. Abundances of Cr are, however, substantially higher in AGV2, BCR2, GSP2 and especially DTS2.     

ICP-AES法同时测定玻璃组份中的Ca、Mg、Ti、Fe、Pb、Cd、Al、Si、B、Zn、Cu元素

建立了一种用电感耦合等离子发射光谱(ICP-AES)法测定玻璃成份的简便、快速、准确、精密度好的方法．研究了样品的处理、标准样品的配制、谱线干扰等问题,并采用和基体匹配的方法消除基体的影响,进行了标准样品的分析、对照、精密度等试验,均取得了满意的结果．     

Valence of elements in HgBa2Can-1CunO2n+2+d (n=1, 2, 3, 4)

Valence of elements in HgBa2Can-1CunO2n+2+d (n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence for the highest Tc sample. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produce more carriers than argon annealed samples.     

Determination of mercury, selenium, bismuth, arsenic and antimony in human hair by microwave digestion atomic fluorescence spectrometry

A novel method for determination of Hg, Se, Bi, As and Sb based on microwave digestion followed by continuous flow vapour generation atomic fluorescence spectrometry was developed. The digestion for Hg was based on a two stage digestion involving HNO(3) and H(2)O(2), whilst for the hydride forming elements a common digestion using HCl and H(2)O(2) was found to be the most effective. The instrumentation and chemistry were optimised in order to provide the best accuracy and precision. The method detection limit for hair samples was found to be 0.2 ng g(-1) for Hg and between 2 and 10 ng g(-1) for the hydride forming elements. The atomic fluorescence detector showed excellent linearity over the concentration ranges studied with linear correlation co-efficients between 0.99984 and 0.99997. To validate the accuracy of the method a human hair certified reference material (GBW 0706) was analysed and excellent agreement with the certified value was obtained for all elements.     

直读光谱法测定CD4MCu不锈钢中碳、镍、铬、铜、钼

应用光电直读光谱法测定了不锈钢(CD4MCu)中碳、镍、铬、铜及钼5种元素。通过下述三项措施提高了方法的准确度和精密度:共存元素的干扰校正;增加制作各元素的标准工作曲线时所用的标准样品数,用了两套标准共13块光谱分析用标准样品;选择样块上合适部位作为光谱激发点。上述5种元素的测量范围(质量分数)依次为0.02%～0.35%,3.50%～28.0%,6.50%～32.0%,0.05%～5.0%及0.05%～4.0%。对方法的精密度做了试验,测得相对标准偏差(n=11)为碳4.8%,镍、铬、钼0.4%,铜2.3%。应用此方法分析了5个不锈钢(CD4MCu)样品,所测得数据与用GB标准中化学法所测得的结果完全一致。     

Preconcentration neutron activation analysis of trace elements in seawater by coprecipitation with 1-(2-thiazolylazo)-2-naphthol,pyrrolidinedithiocarbamate and N-nitroso-phenylhydroxylamine

A method has been developed for the simultaneous preconcentration of Cd(II), Co(II), Cu(II), Hg(II), Mn(II), Th(IV), U(VI), V(IV) and Zn(II) from 500–1000 ml of water samples by coprecipitation using a combination of 1-(2-thiazolylazo)-2-naphthol, ammonium pyrrolidinedithiocarbamate and ammonium salt of N-nitroso-phenylhydroxylamine. The elemental contents have been measured by neutron activation analysis using different schemes of irradiation, decay and counting periods. Quantitative recoveries of all the above elements have been achieved between pH 6.0 and 7.2. For most of the elements, the enrichment factors are of the order of 10⁴. The precision, expressed in terms of relative standard deviation, and accuracy of measurements are within ±5–10%. The detection limits are in the ppb range. The method has been applied to sea and drinking water samples and biological materials.     

X-ray fluorescence determination of As, Bi, Co, Cu, Fe, Ni, Pb, Se, V and Zn in natural water and soil extracts after preconcentration of their pyrrolidinedithiocarbamates on cellulose filters

A simple method for the elements preconcentration on thin-layer paraffin-treated cellulose filters was proposed. It was found that pyrrolydinedithiocarbamates of As(III), Bi, Cd, Co, Cu, Fe(III), Ni, Pb, Se(IV), V(V) and Zn obtained after mixing of sample (3-5 ml min⁻¹) and reagent (0.7-1.0 ml min⁻¹) streams were quantitatively recovered from 100 ml sample. The sample acidity was adjusted to pH 4.8-5.2 for preconcentration of Cd, Co, Cu, Fe(III), Ni, Pb, V(V) and Zn, and to 2 M HCl for preconcentration of As, Bi and Se. The optimum reagent concentration was found to be 0.1%. The elements were determined on the filters by X-ray fluorescence spectrometry. The detection limits achieved were 0.1-4.0 μg of element on the filter. Relative standard deviation (R.S.D.) was not higher than 0.08 while determining 5-50 μg of elements on filter. Accuracy and precision of the technique proposed were evaluated by the analysis of spiked natural samples.     

X射线荧光光谱法测定超硬铝合金中成分

叙述了用SRS 300型X射线荧光光谱仪测定超硬铝合金中铜、镁、锌、铁、硅、锰、铬、镍、钛、锆的X射线荧光光谱分析方法。试样用车床加工至表面平整、光滑,采用强度校正模型,由计算机拟合回归曲线。此法测定结果与常规湿法化学法测定结果相符。     

ICP-AES法测定化妆品中铅、镉、砷、汞、锑、铬、镍、钡、锶等禁限用元素含量

建立了化妆品中铅(Pb)、镉(Cd)、砷(As)、汞(Hg)、锑(Sb)、铬(Cr)、镍(Ni)、钡(Ba)、锶(Sr)含量的电感耦合等离子体原子发射光谱法(ICP-AES)同步检测技术。采用微波消解,在较难消化的化妆品中加HF进行消化,铑(Rh)为内标元素消除基体干扰,以配备耐HF进样系统的ICP-AES进行测定。在0～1.0 mg/L范围内呈现良好的线性关系(相关系数≥0.9999),Pb、Cd、As、Hg、Sb、Cr、Ni、Ba、Sr检出限分别为0.0016,0.0007,0.0021,0.0013,0.0003,0.0009,0.0008,0.0009,0.0021 mg/L,方法回收率80.2%～111%,精密度1.7%～8.2%。结果表明,该方法适用于检测基体复杂的化妆品中Pb、Cd、As、Hg、Sb、Cr、Ni、Ba、Sr。     

不同酸体系对PM2.5中重金属测定的影响

采用3种消解体系对聚四氟乙烯滤膜采集的PM2.5样品进行消解,利用电感耦合等离子体质谱法测定样品中15种重金属元素。比较了硝酸–盐酸(A)、硝酸–过氧化氢(B)、硝酸–氢氟酸–高氯酸(C)3种体系的消解效果,分析了南京市PM2.5中重金属含量,并与文献值进行了比较。结果表明,A,B,C 3种体系测定结果的相对标准偏差的平均值分别为7.9%,9.9%和17.2%,加标回收率分别为80.5%~111.0%,87.5%~120.0%,74.1%~113.0%。C体系测定结果偏高,操作步骤繁琐,精密度差;A,B体系具有试剂用量少,精密度好,准确度高等优点,能满足环境空气PM2.5中多元素同时测定的要求。