X射线荧光光谱法快速测定费托蜡中铁

通过对费托蜡(合成蜡、渣蜡)创新制样与装样、测试条件优化,利用仪器自带的基本参数法无标样半定量分析软件,建立了X射线荧光光谱(XRF)测定费托蜡中Fe的方法。测定的相对标准偏差<1%、典型分析时间10 min/样,无需标样。与ICP-AES测定结果相比较,相对误差低于10%,同时降低了蜡样测试对仪器真空度或分光晶体产生的不良影响。     

X射线荧光光谱熔融法测定锶永磁铁氧体中各组分含量

本文使用自制标准样品,采用混合熔剂熔融样品,用X射线荧光光谱法(XRF)测定锶永磁铁氧体半成品中Fe,Sr,Si等元素的含量.熔融制样有效地消除了矿物效应,并降低了基体效应的影响.实验结果表明,本法准确度高,重现性好,平行测定11次相对标准偏差(RSD)可达到0.1%.该方法用于实际样品分析,其结果与传统化学分析方法结...     

X-射线荧光光谱分析中粉末制样误差的Monte Carlo研究

粉末压片制样方法,简便快速,无需昂贵的铂-黄金坩埚,在XRF分析中一直被广泛地应用。R.P.Gardner等人用一种统一的推导方法概述了前人所建立的各种XRF强度与粉末粒度、压紧率(packing fraction)之间的数学关系。对分析工作者所关心的另一重要问题-粉末制样误差与粒度等因素的关系,国内外尚未见有深入研究报告,本文用Monte Carlo方法对此作一初步探讨。一.模型假设(参见图1) (1)样品具有相对于X-射线穿透深度而言的无限厚度和无限截面积,且仅由对X-射     

微波消解电感耦合等离子体光谱法测定碳化硼中痕量杂质元素

1引言碳化硼(B4C)陶瓷由于具有极高的硬度、优异的耐磨性能、优良的高温稳定性和化学稳定性以及轻质等优良特性而受到人们的极大关注,已在某些领域内得到了广泛应用。研究表明碳化硼中微量乃至痕量杂质元素都会影响其性能。电感耦合等离子体原子发射光谱法(ICP-AES)分析通常要求将样品处理成溶液雾化进样分析。在常压常温下,即使使用氢氟酸、碳化硼也难于分解。熔融样品则会引入大量的熔剂,需要稀释制样,影响样品痕量元素检测,且要使样品完全分解和分析也比较困难。本实验使用微波高压消解系统消解碳化硼样品,并用ICP-AES测定了碳化硼…     

废弃线路板化学分析采样、制样及检测方法

介绍废弃线路板中有回收价值元素和有害物质分析的采样、制样及检测技术。样品经过分类采样、剪切破碎和高温灰化制样,采用样品全分析或副批混合样分析。通过提高称样量、多次测定求平均值的办法,火试金富集-重量法测定贵金属金、银。湿法王水溶解样品,碘量法测定主体元素铜。电感耦合等离子体发射光谱(ICP-AES)法测定其它杂质元素,被测元素质量浓度在0~10μg/mL范围内与光谱强度呈良好线性关系,相关系数均大于0.9998。测定结果的相对标准偏差小于10%(n=5),加标回收率为97.0%~102.5%。该方法简单、快速,有效地解决了线路板样品不均匀而难采样,以及硬度、韧性强制样难,金属易包裹难分解的技术瓶颈,测定结果准确,具有代表性。该方法适用于废弃线路板化学成分分析,其它废弃电子产品检测可参考此方法。     

萤石成分分析方法的标准现状与研究进展

萤石是一种重要的战略性非金属矿产资源,本文对中国国家标准、行业标准、国际标准（ISO）、美国标准（ASTM）以及俄罗斯标准（GOST）中的萤石成分分析标准方法的现状进行了介绍。对近年来X射线荧光光谱法（XRF）、电感耦合等离子体发射光谱法（ICP-AES）、电感耦合等离子体质谱法（ICP-MS）、激光诱导击穿光谱法（LIBS）等技术在萤石成分分析中的应用以及标准物质/标准样品研制情况进行了总结和评述。文章认为,萤石分析测试技术标准体系相对完备,XRF、ICP-AES、ICP-MS等仪器分析测试技术已普遍应用于萤石样品实验室分析,建议尽快研究并建立萤石中稀土等微量元素测定的标准方法,并开展相应标准物质/标准样品的研制,同时应大力开展原位在线分析技术的研究与开发,以适应工业在线自动化监测的需求,LIBS与在线XRF技术联合在萤石在线分析方面具有良好的应用潜力。     

富钴结壳铂族元素超细标准物质的研制

2个富钴结壳铂族元素(PGEs)标准物质MCPt-1和MCPt-2的原样分别由中国和俄罗斯取自中太平洋海山和西太平洋麦哲伦海山区.样品经风干、选配,先经球磨制备成74 μm(200目)粉体样品,再用气流磨将其进一步加工成具有超细粒度的均匀样品.采用激光粒度仪检测样品的粒度分布,其平均粒度分别为1.8和1.5 μm(约2 000目).采用高精度的X射线荧光光谱法(XRF)和电子探针方法分别检验了6个主、次元素在mg和μg取样量水平上的均匀性,用LA-ICP-MS检验了包括Pt在内的40多个痕量元素在μg量水平上的均匀性.样品采用锍镍火试金和Carius管预富集和酸溶消解,除Rh外均采用同位素稀释电感耦合等离子体质谱测定(ID-ICP-MS),确定了MCPt-1和MCPt-2中6个铂族元素的标准值;采用XRF和ICP-AES、ICP-MS方法相结合给出了62个主、次和痕量元素的信息值.最小取样量分别为1 g(测定PGEs)和2 mg(测定其他元素).     

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.     

K金饰品中金含量的检测方法比对

目前实验室对金首饰金含量的主要检测方法为火试金法、X射线荧光光谱（XRF）法和电感耦合等离子体-原子发射光谱（ICP-AES）法.当测试结果出现争议时,国家标准GB 11887-2012中以火试金法作为仲裁方法.采用上述3种不同的金含量测试方法分别对14K、18K和22K饰品的金含量进行测定,并对3种方法检测结果进行比对.结果发现,在3种方法均可满足样品分析对准确度的要求时,以火试金法为基准,XRF法与ICP-AES法对同纯度的金首饰检测结果的相对误差差异较大,XRF法的结果可满足检测要求,而ICP-AES法的结果无法满足检测要求.其中,XRF法的相对误差为0.05%~0.77%,ICP-AES法的相对误差为1.24%~3.89%.从结果来看,低纯度的K金饰品使用XRF法的检测结果要更接近于火试金法.     

铝土矿有效铝含量测定影响因素研究

研究了影响铝土矿中有效铝含量测定的主要影响因素。主要探讨了样品粒度、均匀性对有效铝溶出效果的影响及样品组成对有效铝含量大小的影响。利用电感耦合等离子体原子发射光谱(ICP-AES)法测定铝土矿中有效铝含量、X射线荧光光谱(XRF)法测定铝土矿中总氧化铝含量和其它杂质成分含量,借助X射线衍射光谱(XRD)法对样品进行物相组成分析,确定各主要组成的结构和占比。将样品制备至0.106mm以下,均匀性好,精密度高,有效铝溶出率高。样品物相组成中三水铝石占比高,一水铝石占比低,与氢氧化钠低温条件更易反应,使溶出率高。通过加标回收实验验证方法的加标回收率为99.1%～101%,实验标准偏差为0.14%,相对标准偏差为0.003%,可对铝土矿有效铝的监控提供技术支撑。     

掺希土离子Eu3+的BaTiO3超细微粉的制备及物性表征

近年来人们对材料及由材料制备的元件提出了高可靠性、多功能等要求。为了达到这种要求,人们从多种途径进行了探索,其中,对现有材料进行掺杂就是很有效的方法之一［１,２］。本文报道对ＢａＴｉＯ３超细微粉进行Ｅｕ３＋的有效掺杂并对其进行了物性表征。１实验部分１...     

Generality of the scattering dilution method for FT-IR spectrometry

The scattering dilution method (SDM) was proposed as one measurement method of powders for FT-IR spectrometry. It was confirmed that SDM was a general measuring method for powders with a higher or lower refractive index for all cases. In the case of obtaining the IR spectra of powders, although we might not need to use SDM for transparent or non-colored samples, it is worthy to first utilize SDM for colored samples or mixture samples.     

超细聚酰胺6粒子增韧聚丙烯体系的研究

采用磨盘形力化学反应器室温下制备了聚丙烯 (PP) /聚酰胺 6 (PA6 )超细粉体 ,研究了其粒度、粒度分布及PA6超细粒子填充对PP力学性能的影响 .结果表明 ,磨盘形力化学反应器可有效实现PP/PA6的粉碎 ,所得粉体平均粒径达微米级 ,初级粒子尺寸甚至可达纳米级 ,粒度分布呈双峰分布状态 .在PA6和PP熔点之间的温度下加工可制得PA6超细粒于填充的PP/PA6共混体系 ,其力学性能明显好于PP/PA6简单共混体系 ,30 %PA6用量下 ,拉伸强度由 2 3 .2MPa提高至 2 9 3MPa ,Izod缺口冲击强度由 4.6 2kJ/m2 提高到6 .34kJ/m2 .形貌分析结果表明 ,由于基本保持了PA6超细粉体的原始尺寸 ,填充体系中PA6相区尺寸小、分布均匀 ,与使用增容剂得到的相区结构类似 .     

电感耦合等离子体质谱法测定地质样品中银研究进展

应用电感耦合等离子体质谱（ICP-MS）测定地质样品中银时,锆、铌等元素干扰银的测定,造成准确度低、测定偏差大。采用银的富集、王水偏提取和化学分离法等方法可对干扰元素预分离,从而准确测定样品中银;而应用干扰校正方程及碰撞/反应池（CRC-ICP-MS）、膜去溶（DSN-ICP-MS）、激光剥蚀（LA-ICP-MS）和高分辨质谱（HR-ICP-MS）等新技术,能够更加方便、准确测定地质样品中银。     

氧化石墨烯/壳聚糖微球吸附-电感耦合等离子体质谱法测定地质样品中痕量钽EI北大核心CSCD

建立了氧化石墨烯/壳聚糖微球吸附-电感耦合等离子体质谱法测定地质样品中痕量Ta的方法。合成了氧化石墨烯/壳聚糖微球,将其应用于地质样品中痕量Ta的分离富集,采用电感耦合等离子体质谱对富集后的试液进行测定。对氧化石墨烯含量、配体种类和浓度、pH、吸附时间、吸附剂用量等吸附条件和洗脱剂类型、体积、洗脱时间等洗脱条件进行了优化,在优化的条件下,对地质样品标准物质进行测定,Ta的方法检出限为2.0 ng/g,富集倍数为26.7倍。     

The influence of morphology of ultra-fine calcite particles on decomposition kinetics

The decomposition kinetics of reference calcite and three ultra-fine samples with different morphologies are investigated. The kinetic parameters and rate equation are obtained according to the methods reported in our previous studies. Compared with the reference calcite, a considerable diminution of the activation energy E _a up to 70–80 kJ mol⁻¹ is observed in the case of three ultra-fine samples. There are also some distinct differences concerning the activation energy of each of the ultra-fine sample. This may have something to do with the particle morphology revealed by TEM and SEM measurements. XRD measurements of four calcite samples show that large strain exists in the crystal lattice in the case of ultra-fine calcite samples. This may give a reason to their abnormal decomposition behavior.     

X-ray fluorescence analysis in environmental radiological surveillance using HPGe detectors

X-ray fluorescence (XRF) has been proven to be a valuable tool for determining trace quantities of heavy metals, such as uranium and lead, in different types of samples. The present paper demonstrates the applicability of XRF spectrometry to measure the concentrations of these heavy metals in samples from natural ore and soil. The values of uranium concentrations in rock from the Peña Blanca uranium ore, in Chihuahua, México, were calculated for the purpose of precertifying the rock powders samples. The comparison with other techniques, such as inductively coupled plasma atomic emission spectrometry, atomic absorption spectrometry, alpha spectrometry and electron microscopy, was used to complete the precertification process, so that the sample powders may be used as secondary standards. The source-sample-detector geometry and the incident angle are the most important factors for obtaining low detection limits. The selected system uses a ⁵⁷Co source of about 0.1 mCi to excite the K X-rays from uranium and lead. X-rays were recorded on a CANBERRA HPGe coaxial detector. The comparative results for two incident angles (90° and 180°) performed previously by other authors show that the best geometry is the backscattering geometry. In the present paper, using EGS4 code system with Monte Carlo simulation, it was possible to determine the location and distribution of background produced by the Compton edge in the optimized geometry. This procedure allowed to find the minimum detectable concentration of uranium and lead, which was experimentally calculated using standards. The possibility of performing in vivo measurements rapidly and easily, as well as the factors affecting accuracy and the minimum detectable concentration in several samples are also discussed.     

Thermal analyses applied to ceramic nanopowders: from synthesis to sintering

The free sintering of ceramic powders into fully dense nanostructured materials is still a challenging process, even more complex when nanostructured transition alumina is used as starting powder. In this paper, biphasic (Alumina–YAG) and triphasic (Alumina–YAG–ZrO₂) composite powders were produced by doping the same nanocrystalline transition alumina with inorganic precursors of the second-phases, which were subsequently yielded under controlled thermal treatments. The added dopants significantly increased both the θ- to α-phase transformation and the sintering temperatures, making even more difficult the retention of the starting nanometric grain size into the final dense materials. Thermal analyses (such as TG–DTA and dilatometry) are here used to support most of the ceramic processing steps involved in a successful elaboration of the desired ultra-fine structures. In fact, the thermal pre-treatments of the doped powders were set up on the ground of the DTA–TG curves whereas the dilatometric analyses were exploited to design optimised sintering cycles, through which the green bodies were successfully consolidated into fully dense materials, characterised by highly homogeneous and tailored micro/nanostructures.     

A new strategy of solution calibration in laser ablation inductively coupled plasma mass spectrometry for multielement trace analysis of geological samples

Because multielement trace analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is often limited by the lack of suitable reference materials with a similar matrix composition, a novel quantification strategy using solution calibration was developed. For mass spectrometric multielement determination in geological samples a quadrupole-based LA-ICP-MS is coupled with an ultrasonic nebulizer (USN). In order to arrange matrix matching the standard solutions are nebulized with a USN during solution calibration and simultaneously a blank target (e.g. lithium borate) is ablated with a focused laser beam. The homogeneous geological samples were measured using the same experimental arrangement where a 2% nitric acid is simultaneously nebulized with the USN. Homogeneous targets were prepared from inhomogeneous geological samples by powdering, homogenizing and fusing with a lithium borate mixture in a muffle furnace at 1050 degrees C. Furthermore, a homogeneous geological glass was also investigated. The quantification of analytical results was performed by external calibration using calibration curves measured on standard solutions. In order to compare two different approaches for the quantification of analytical results in LA-ICP-MS, measured concentrations in homogeneous geological targets were also corrected with relative sensitivity coefficients (RSCs) determined using one standard solution only. The analytical results of LA-ICP-MS on various geological samples are in good agreement with the reference values and the results of other trace analytical methods. The relative standard deviation (RSD) for trace element determination (N = 6) is between 2 and 10%.     

A new strategy of solution calibration in laser ablation inductively coupled plasma mass spectrometry for multielement trace analysis of geological samples

Because multielement trace analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is often limited by the lack of suitable reference materials with a similar matrix composition, a novel quantification strategy using solution calibration was developed. For mass spectrometric multielement determination in geological samples a quadrupole-based LA-ICP-MS is coupled with an ultrasonic nebulizer (USN). In order to arrange matrix matching the standard solutions are nebulized with a USN during solution calibration and simultaneously a blank target (e.g. lithium borate) is ablated with a focused laser beam. The homogeneous geological samples were measured using the same experimental arrangement where a 2% nitric acid is simultaneously nebulized with the USN. Homogeneous targets were prepared from inhomogeneous geological samples by powdering, homogenizing and fusing with a lithium borate mixture in a muffle furnace at 1050?°C. Furthermore, a homogeneous geological glass was also investigated. The quantification of analytical results was performed by external calibration using calibration curves measured on standard solutions. In order to compare two different approaches for the quantification of analytical results in LA-ICP-MS, measured concentrations in homogeneous geological targets were also corrected with relative sensitivity coefficients (RSCs) determined using one standard solution only. The analytical results of LA-ICP-MS on various geological samples are in good agreement with the reference values and the results of other trace analytical methods. The relative standard deviation (RSD) for trace element determination (N = 6) is between 2 and 10%.