Accuracy analysis of iron content of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum

The accuracy(repeatability and reproducibility) of the iron content analysis of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum is not better than that of flame atomic absorption spectrometry, sometimes it exceeds the quality control limit.Influences, such as current, voltage, equipment(internal circulating water, 10%CH4+90%Ar, and vacuum) checking, instrument monitoring, sample cleaning, and oper-ators, were investigated by means of 6-sigma and lean operations to improve accuracy.

Potential Applications of X-ray Fluorescence Core Scanner in Elemental Analyses of the Muddy Sediments on the Coastal Shelves of China and in Ecological Study

Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study on environmental information recorded in mud areas because of complicated sedimentary environment and variable sedimentary rate, requires a fast and economical method. In this study, we investigated the potential of X-ray fluorescence core scanner （XRFS）, a fast analytical instrument for measuring the elemental concentrations of muddy sediments, and observed a significant correlation between the element concentrations of muddy sediments determined by regular X-ray fluorescence spectrometer （XRF） and XRFS, respectively. The correlations are mainly determined by excitation energy of elements, but also influenced by solubility of element ions. Furthermore, we found a striking link between A1 concentrations and marine-originated organic carbon （MOC）, a proxy of marine primary productivity. This indicates that MOC is partly controlled by sedimentary characteristics. Therefore, XRFS method has a good potential in fast analysis of a large number of muddy sediment samples, and it can also be used to calibrate MOC in ecological study of coastal seas.

Application of a Portable XRF Spectrometer for <i>In-Situ</i>and Nondestructive Investigation of Pigments in Two 15th Century Icons

A simple portable X-Ray Fluorescence (XRF) spectrometer was successfully used for in-situ and nondestructive identification of the painting materials in two 15th century icons from the Onufri Museum in Beart, Albania. The spectrometer is based on a low power X-ray tube, a thermoelectrically cooled Si PIN detector and the spectrum acquisition system. It was assembled and adjusted at our laboratory for the investigation of the icons. A small number of pigments were clearly identified by X-Ray Fluorescence (XRF) measurements in both icons. This includes Lead white for the white color, gold and yellow ochre for the yellow color, red lead, cinnabar and red ochre for the red color, as well as cooper based pigments for the green color. At the same time, the investigation raised some new questions that need further investigations by the use of additional analytical techniques. The results show that in both icons are used similar pigments, which are in accordance with the Byzantine icon painting tradition.

Analysis of nickel distribution by synchrotron radiation X-ray fluorescence in nickel-induced early- and late-phase allergic contact dermatitis in Hartley guinea pigs

Background: Nickel-induced allergic contact dermatitis (Ni-ACD) is a global health problem. More detailed knowledge on the skin uptake of haptens is required. This study aimed to investigate the penetration process and distribution of nickel in skin tissues with late phase and early phase of Ni-ACD to understand the mechanisms of metal allergy. Methods: Forty Hartley guinea pigs were divided into four groups according to the NiSO4 sensitizing concentration and the NiSO4 challenged concentration: the 5% NiSO4-group, 5% to 10%(sensitization-challenge;late phase group);10% NiSO4-group, 10% to 10%(sensitization-challenge;early-phase group);and the positive and negative controls. Pathological biopsies were performed on each group. The depth profile of nickel element concentration in the skin of guinea pigs was detected by synchrotron radiation micro X-ray fluorescence spectroscopy (SR-μ-XRF) and micro X-ray absorption near-edge spectroscopy (μ-XANES). Results: In each section, the nickel element concentration in both the 5% NiSO4-group and 10% NiSO4-group was significantly higher than that in the negative control group. In the upper 300-μm section of skin for the early phase group, the nickel element concentration was significantly higher than that in the lower section of skin. In deeper sections (>200 μm) of skin, the concentration of nickel in the early phase group was approximately equal to that in the late phase group. The curve of the late phase group was flat, which means that the nickel element concentration was distributed uniformly by SR-μ-XRF. According to the XANES data for the 10% NiSO4 metal salt solution, structural changes occurred in the skin model sample, indicating that nickel was not present in the Ni^2+ aqueous ionic state but in the nickel-binding protein. Conclusions: This study showed that the distribution of the nickel element concentration in ACD skin tissue was different between the early phase and late phase groups. The nickel element was not present in the Ni^2+ aqueous ionic state but bound with certain proteins to form a complex in the stratum corneum in ACD model tissue.

一种面向港口溢油监测的小型激光荧光遥测系统

目前,针对港口溢油巡航监测缺乏行之有效的技术手段。为探索激光诱导荧光光谱技术应用于港口溢油监测的可行性,以微型光纤光谱仪搭建小型激光荧光遥测实验系统,并对其性能进行测试分析。结果发现,在光谱仪曝光时间设为最小(1.11 ms)的情况下,环境光对荧光测量仍会产生影响,利用减背景法可以有效去除溢油荧光信号中环境光的影响;在相同条件下,系统测得不同油质溢油样品的荧光光谱表现出不同的光谱特征,轻质油较重质油的荧光峰蓝移、荧光更强;在上述环境光背景影响和光谱测量分析的基础上,进一步测试了系统的信号探测稳定性,结果显示,系统重复测量的相对标准偏差RSD=2.54%,表明该系统具有较好的信号探测稳定性。综上,基于微型光纤光谱仪的小型溢油激光荧光遥测系统可望在近岸港口溢油巡航监测中发挥重要作用。

微束X射线荧光光谱仪测定射击残留物特征元素分布图的应用研究

通过优化定距射击样本采集条件,考察了六四手枪在不同距离(0,2,5,10,15,20,25,30,35,40,45,50,60,80,100,120,140,170,200,300,500,1 000 cm)垂直射击PU布块靶体时相关元素(氯、钾、硫、锑、锡、钡、铅、汞、砷、铁、铜、锌、钛、钙、铑)的区域扫描图,建立了微束X射线荧光光谱(μ-XRF)面扫描技术分析射击样本的方法,并建立了六四手枪射击残留物特征元素分布图形随射击距离而变化的数据模型,同时对所得数据进行了归一化处理。本方法可协助推断射击距离,为涉枪案件的侦查与诉讼提供科学证据。

原位微区X射线荧光光谱分析装置与技术研究进展

原位微区X射线荧光(Micro-XRF)光谱分析技术是X射线光谱学领域一重要分支。近年来X射线毛细管光学透镜聚焦技术不断进步,以实验室X光源为基础的原位微区X射线光谱分析装置与应用技术快速发展,已成功应用于多领域样品的原位、多维、动态和非破坏性微区分析。文章介绍了近年来X射线毛细管光学透镜技术发展和原位微区X射线光谱分析装置研制进展,对近年来micro-XRF光谱分析技术在大气气溶胶颗粒物分析与来源识别、考古样品产地和真伪鉴别、古气候古环境重建研究中沉积纹层样品元素分析,以及刑侦科学中指纹样品的鉴定等应用领域进行了系统介绍,阐述了micro-XRF光谱分析技术性能的影响因素(空间分辨率和强度增益)。micro-XRF光谱分析技术不仅可以获取样品表面的信息,还能够获取样品内部的信息,成为目前国际上一门迅速发展的竞争技术。我国在毛细管透镜制造技术与性能研究,以及micro-XRF应用领域取得了重要进展。由于X射线焦斑尺寸对能量的依赖性以及样品基质对X射线的吸收效应,在微区定量分析中易引入较大误差,利用X射线毛细管透镜获取更小光斑尺寸与高稳定性的X射线光束,提高micro-XRF分析技术的空间高分辨率性能和对基体效应进行校正实验将是今后一个重要的研究目标和分析研究难点。

清代红绿彩瓷器无损分析研究

红绿彩瓷器是我国陶瓷史上一种重要的釉上彩瓷器,分析其彩料的化学组成和物相结构对其烧制工艺的研究有很重要的意义。但由于瓷器表面的不平整和彩料分布的不均匀性,导致其不满足传统的1 mm×10 mm线光源的X射线衍射仪对样品的测试要求。而毛细管聚焦的X射线衍射仪采用点光源的方式照射样品,毛细管X光透镜对Cu-K_(α)的能量有高达3个数量级的放大倍数,同时具有低的发散度,能实现样品直径100μm的微区和直径3 mm的常规X射线衍射分析,非常适合古陶瓷类样品矿物结构的无损分析的研究。因此,应用毛细管聚焦的微束X射线荧光谱仪和毛细管聚焦的X射线衍射谱仪对江西景德镇出土的清代红绿彩瓷的白釉和釉上彩料的化学成分和物相结构进行分析,并对红绿彩瓷彩料中2 mm×2 mm感兴趣区域内多元素分布和矿物相的分布进行了二维扫描分析。结果表明,Cu为绿彩的主要着色元素,在绿彩中的含量为0.02%,部分以Pb_(8)Cu(Si_(2)O_(7))_(3)(PDF 31-0464)晶相形式存在;Fe为红彩的主要着色元素,Fe含量为1.63%,部分Fe元素以Fe_(2)O_(3)(PDF 47-1409)的晶相形式存在;其中Pb在绿彩和红彩中的含量分别为41.49%和6.29%,其主要作用是使彩料的熔点降低,部分Pb在700~800℃的烧制过程中与Cu元素和Si元素相结合以Pb_(8)Cu(Si_(2)O_(7))_(3)(PDF 31-0464)晶相形式存在。从扫描区域内的元素分布图和晶相分布图可以看出,彩料原料中着色元素Cu和Fe的矿物晶相与Cu和Fe的元素分布不一致,表明原料中原有的Cu和Fe的矿物晶相在烧制过程中基本上都消失了,仅剩余或生成部分Fe_(2)O_(3)晶相;白釉中存在莫来石晶相,说明白釉是在高温下烧制而成;其中Pb_(8)Cu(Si_(2)O_(7))_(3)晶相的形成温度在750℃左右,因此可以进一步说明清代红绿彩的绿彩料是在低温下烧制而成。以上结果说明,毛细管聚焦的微束X射线荧光和毛细管聚焦的微束X射线衍射谱仪在文物的科技研究中有着重要的应用前景。

X射线荧光光谱仪及其分析技术的发展

按照获得和分辨特征X射线荧光光谱的方式,X射线荧光光谱仪可以分为波长色散X射线荧光光谱仪(WDXRF)和能量色散X射线荧光光谱仪(EDXRF)两大类。依照这一分类,论述了X射线荧光光谱仪在设备装置和配套方法方面的新状况。X射线荧光光谱仪整机现在向着小型化、智能化、多功能方面发展,仪器各部件也随着研究的深入而得到了更进一步地改进,在这一基础上,仪器可分析元素的含量范围得到了拓展,方法也得到了丰富。目前,X荧光光谱仪开发了微区面分布的元素成像分析方法、高级次谱线分析方法、薄膜分析方法等新的方法,对这些新方法作以介绍,同时也对基本参数法(FP法)的新近发展作了说明。

毛细管X光透镜聚焦的微束X射线荧光谱仪的研发及应用

针对不同样品的分析需求,本文设计了几种不同类型的微束X射线荧光谱仪。用高精度激光位移传感器实时校正样品表面被测量点与毛细管透镜出端之间的距离,以减少形状不规则的古陶瓷样品测量时带来的误差;利用毛细管X光透镜传输能量高于25keV的X射线效率低的特点,将其应用于高铅釉瓷器彩料的无损分析中;采用大功率X射线源,扫描分析了大米中K、Ca等元素分布;以人民币5角硬币为例,研究了能量色散的微束X射线衍射方法。研究结果表明,本文研发的微束X射线荧光谱仪在生物样品和文物样品的分析研究中有广泛的应用前景。

一种毛细管聚焦的便携式微束X射线荧光谱仪

基于毛细管X光透镜技术的便携式能量色散X射线荧光分析因其无损分析等优点成为分析文物样品的有利工具。但由于文物样品的表面不平整或弧度以及毛细管X光透镜聚焦X射线的特点,导致在测量过程中样品测量点与毛细管X光透镜出端之间的距离产生变化,引起照射样品的X射线束斑大小发生改变,从而影响测量结果的准确性和元素区域扫描的分辨率。介绍了本实验室自行研发的一种新型便携式微束X射线荧光谱仪,此谱仪主要是由SDD X射线探测器、30W低功率X射线管、毛细管X光透镜、CCD和一个新型闭环控制系统构成。该闭环控制系统是在激光位移传感器能够精确控制样品测量点到毛细管X光透镜出端距离的基础上,结合LabVIEW语言环境下开发的计算机控制程序以及步进电机、样品台等器件组成。基于此系统,该实验室研发的便携式微束X射线荧光谱仪在测量过程中可以时刻保证照射样品的X射线光斑大小固定不变。同时,该谱仪还可以通过调整样品测量点到透镜出端的距离来选择不同尺寸的X射线照射光斑。为了验证设备的可行性,使用该便携式微束X射线荧光谱仪在激活激光位移传感器和关闭激光位移传感器两种情况下测量了一块表面不平整古陶瓷样品釉彩层中K,Ca,Zn和Fe等元素的含量及分布,并将测量结果进行了对比。结果显示,在激活激光位移传感器的情况下测得的样品微区元素含量与真实值较接近,扫描区域元素分布图的分辨率更好,表明本谱仪基于激光位移传感器开发的自动调整样品测量点到透镜出口端距离的闭环控制系统能有效的减少由于样品表面不平整或弧度带来的测量误差,弥补了现有微束X射线荧光谱仪在此方面的不足。因此,本便携式微束X射线荧光谱仪在无损分析检测文物方面具有潜在的应用前景。

基于数字微镜器件的原子荧光色散检测技术研究

基于氢化物发生-原子荧光光谱法(HG-AFS)研制了一套由数字微镜器件(Digital micromirror device,DMD)作为空间光调制器、光栅作为分光器、光电倍增管(Photomultiplier Tubes,PMT)作为检测器的紫外DMD光谱仪。通过采用高紫外透射率DMD和改进信号采集系统等方式,提高光谱仪对180～320 nm范围内微弱荧光信号的检测能力。在实验平台上,对DMD的翻转控制参数和PMT负高压进行了优化,并对4种元素(As、Sb、Bi、Hg)的发射谱线和激发荧光进行了分析,对由空心阴极灯造成的光源散射干扰进行了讨论。结果表明,紫外DMD光谱仪初步实现了对HG-AFS荧光信号的检测和分析。此仪器具有结构简单、不含宏观移动部件、检测速度快等优点,完成一次全谱扫描分析仅需要0.848 s。

高频熔融-X射线荧光光谱法测定拟薄水铝石中多种微量和痕量杂质成分

研究了采用高频熔融-X射线荧光光谱法测定拟薄水铝石中SiO_2、Fe_2O_3、Na_2O、K_2O、CaO、ZnO、TiO_2、V_2O_5、P_2O_5等微量和痕量杂质含量。样品以四硼酸锂-偏硼酸锂混合熔剂熔融,以溴化锂为脱模剂,分别在800℃和1 000℃下加热3min,之后在1 150℃下熔融8min,冷却后制成玻璃片,进行测定。用与拟薄水铝石基体及杂质含量相近的氧化铝和氢氧化铝国家标准物质绘制校准曲线,在相同条件下熔融成玻璃片测定各成分荧光强度。当杂质质量分数大于0.001%时,本法测定值与ICP-AES法和AAS法测定值相近,9种杂质成分检出限在0.000 084%~0.005 6%之间,不同成分测定值的相对标准偏差(n=10)在0.36%~8.3%之间。

Preliminary Informative Results on Glass Tesserae from V^th-VI^thCentury AD Mosaics in Albania

This paper discusses some preliminary results regarding raw materials used in ancient glass mosaic tesserae. The studied glass tesserae were recovered during the archeological excavation of the mosaics at the Christian basilicas in Byllis, Lin and Elbasan, which according to the archeologists were built between the end of Vth and beginning of VIth century AD. In the recent years, several studies are performed on opaque coloured glass but in Albania only few studies are performed in this field. These samples are analyzed using optical microscopy and micro X-ray fluorescence. Optical microscopy is used to analyse the microstructure of the glass tesserae. The main elements and trace elements are determined qualitatively from measurements performed with micro X-ray fluorescence. The glass matrix resulted to be very heterogeneous with too many inclusions dispersed on it. Several elements which are responsible for the color and opacity of glass tesserae are determined. Comparisons are made between the same colors of glass tesserae from different archaeological sites.

实物地质资料测试分析技术应用研究——以湖南黄沙坪铅锌矿标本测试为例

开展典型矿床测试分析技术应用研究,提出适合实物地质资料的分析测试技术,加强实物地质资料的预研究能力,提升实物地质资料的服务利用水平。以湖南黄沙坪铅锌矿标本样品测试为例,分别采用便携式X射线荧光光谱仪、电子探针、扫描电镜、X射线荧光光谱仪、电感耦合等离子体质谱仪等分析仪器实施典型矿床分析测试实验。研究结果表明,便携式X射线荧光光谱仪无损测试技术适用于定性、半定量检测,异常查证等预研究,元素定量分析应以X射线荧光光谱法、电感耦合等离子体质谱法为主导,扫描电镜及电子探针微区分析方法配合使用进行矿物定名等研究。

埃迪卡拉纪晚期疑难化石Shaanxilithes在云南会泽朱家箐剖面的首现及其意义

陕西迹(Shaanxilithes)见证了埃迪卡拉纪–寒武纪之交生物演化及生态环境的变化,是埃迪卡拉纪末期标志性的疑难化石,具有全球对比意义。本文首次报道了云南曲靖会泽县大海乡朱家箐剖面灯影组旧城段泥质灰岩中新发现的宁强陕西迹(Shaanxilithes ningqiangensis Xing,Yue and Zhang,1984)。所采集的标本整体形态上呈条带状,边缘呈锯齿状参差不齐,可见环状体分布。通过镜下观察,可发现散落圆盘状单元。将大海乡朱家箐剖面与晋宁六街镇王家湾剖面渔户村组旧城段所产出的Shaanxilithes化石对比后发现,朱家箐剖面的标本宽度更窄,长度更长,碎片化更加明显。通过微区X射线荧光光谱仪(μ-XRF)将朱家箐剖面和王家湾剖面的标本进行对比分析后可知,前者形态在Si、Al、K的元素分布图中显示清晰,而后者的形态主要体现在Fe元素的分布图上;前者化石和围岩中Ca元素的含量远远高于后者;S元素仅在前者存在微量的分布,在后者中未有信号显示。新的化石证据表明Shaanxilithes并非只产出自碎屑岩中,还可以在灰岩中保存。化石μ-XRF的面扫描和半定量分析表明Shaanxilithes可能为伊利石矿物交代,并且说明在不同岩相背景下,风化作用程度的强弱造成两个产地化石的差异性保存。随着研究区域不断扩大,Shaanxilithes相继在华南板块滇东地区、印度西北缘、纳米比亚、华北板块西南缘等地区晚埃迪卡拉世地层中被发现。此次在滇东会泽地区发现的Shaanxilithes,进一步表明该化石分布的广泛性,可作为全球晚埃迪卡拉世地层对比的标准化石。本文结合形态学分析和微区X射线荧光光谱分析,讨论了Shaanxilithes的埋藏学信息与亲缘关系,为探索埃迪卡拉纪–寒武纪过渡时期的生物和生态特征提供了更多视角。

毛细管X光透镜聚焦的微束能量色散X射线衍射分析的研究

微束能量色散X射线衍射(EDXRD)分析在测量小样品或样品微区的物相结构方面具有重要的应用前景。提出了一种采用自行研发的微束X射线荧光谱仪进行微束能量色散X射线衍射分析的研究方法。用便携式毛细管X光透镜聚焦的微束X射线荧光谱仪(焦斑直径为190.7μm)对人民币5角硬币"角"部分长×宽为4mm×4mm的微区进行微束能量色散的X射线衍射扫描测量,并进行数据处理,得到该区域内Cu3Sn(0 8 3)和CuO(2 0 2)等晶相的分布;同时,用台式毛细管X光透镜聚焦的微束X射线荧光谱仪(焦斑直径为31μm)对一颗直径约为1mm的矿石颗粒进行微束能量色散的X射线衍射二维扫描分析,得到扫描区域内SiO2(3 2 9)和Fe2O3(1 1 6)等晶相的分布。结果表明,毛细管X光透镜聚焦的微束X射线荧光谱仪在开展小样品或样品微区的能量色散X射线衍射分析方面具有一定的应用前景。

Proximal sensor-enhanced soil mapping in complex soil-landscape areas of Brazil

Portable X-ray fluorescence(pXRF) spectrometry and magnetic susceptibility(MS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict soil classes using the Random Forest(RF) algorithm. The study was conducted on a 316-ha area featuring highly variable soil classes and complex soil-landscape relationships in Minas Gerais State, Brazil. The overall accuracy and Kappa index were evaluated using soils that were classified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models(DEMs) were created at 5-, 10-, 20-, and 30-m resolutions using contour lines from two sources. The resulting DEMs were processed to generate 12 terrain variables. Total Fe, Ti, and SiO_(2) contents were obtained using pXRF, with MS determined via a magnetometer. Soil class prediction was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important covariates and combining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most accurate maps. The high soil complexity in the area prevented highly accurate predictions. The most important variables influencing the soil mapping were MS, Fe, and Ti. Proximal sensor data associated with terrain information were successfully used to map Brazilian soils at variable spatial resolutions.

The implications of planting mode on cadmium uptake and remobilization in rice: Field experiments across growth stages

Global rice production practices have gradually changed from a reliance on transplanting to direct seeding.Yet how this shift may alter cadmium(Cd)accumulation in rice is poorly known.Here we conducted field experiments with two rice genotypes cultivars that were planted using three methods:via direct seeding(DS),seedling throwing(ST),and manual transplanting(MT).Rice samples were collected during four growth stages.The formation and distribution of iron plaque were analyzed using DCB(dithionite-citrate-bicarbonate)extractions and observed under micro-XRF(micro X-ray fluorescence).The results revealed that,in each growth stage,DS rice was more apt to harbor Cd distributed in the plant’s aerial parts,and the Cd concentration of brown rice from DS was 21.8%–43.3%significantly higher than those from ST and MT at maturity stage(p<0.05).During the vegetative stages,the Cd uptake percentage was higher in DS than MT rice,and those plants arising from the DS method were capable of absorbing more Cd earlier in their growth and development.Conversely,using DS decreased the amount of iron plaque covering the root surface in every growth stage,especially in the critical period of Cd accumulation,such that the roots’middle areas were distinguished by a near-complete absence of iron plaque,thus weakening its role as an effective barrier to Cd uptake from soil.Collectively,this study demonstrated that implementing the DS mode of planting will increase Cd’s distribution in the aboveground parts of rice,and heightening the risk of Cd contamination in grain.