Sulfur analysis of conifer needles by inductively coupled plasma atomic emission spectrometry

Zusammenfassung Nadelproben werden in einem Druckaufschlu\gefÄ\ mit SalpetersÄure aufgeschlossen und die erhaltenen Lösungen mittels ICP-AES auf Schwefel analysiert. Die Messung erfolgt bei 182,04 nm in einem mit Stickstoff gespülten Spektrometer. Die Ergebnisse korrelieren gut mit unabhÄngigen Bestimmungen durch Wickbold-Aufschlu\ und Ionen-Chromatographie. Das Verfahren hat den Vorteil, da\ keine Verluste des Analysenelements auftreten und da\ die Aufschlu\lösung auch für die simultane Bestimmung von Spurenmetallen mit der ICP-AES geeignet ist.     

Bulk analysis by IR laser ablation inductively coupled plasma atomic emission spectrometry

Two laser ablation systems dedicated to bulk analysis were evaluated for steel and PVC samples, using inductively coupled plasma atomic emission spectrometry detection. These systems were characterized by the use of a Nd:YAG laser operating at 1064 nm, the absence of observation device and a large laser spot size. The 1064 nm wavelength was selected to avoid the use of frequency-multiplying optics, and to be less critical to the sampling position. Calibration graphs and limits of detection are given for both types of materials. LODs were in the range 3–120 μg/g for steel, and in the range 0.07–15 μg/g for PVC. In the case of steel samples, similar calibration graph slopes were obtained between polished and unpolished samples.     

Bulk analysis by IR laser ablation inductively coupled plasma atomic emission spectrometry

Two laser ablation systems dedicated to bulk analysis were evaluated for steel and PVC samples, using inductively coupled plasma atomic emission spectrometry detection. These systems were characterized by the use of a Nd:YAG laser operating at 1064 nm, the absence of observation device and a large laser spot size. The 1064 nm wavelength was selected to avoid the use of frequency-multiplying optics, and to be less critical to the sampling position. Calibration graphs and limits of detection are given for both types of materials. LODs were in the range 3-120 microg/g for steel, and in the range 0.07-15 microg/g for PVC. In the case of steel samples, similar calibration graph slopes were obtained between polished and unpolished samples.     

A helium inductively coupled plasma for atomic emission spectrometry

An annular helium inductively coupled plasma (He ICP) was generated at atmospheric pressure. No external cooling was used to stabilize the plasma. Aqueous solution was injected into the plasma without any difficulty. Preliminary results revealed that the annular He ICP was capable of exciting elements such as Cl and Br which possess high excitation energies. Atomic emission detection limits for Cl and Br were improved by factors of 63 and 34, respectively, as compared to the results obtained from the argon inductively coupled plasma. The excitation temperature of the annular He ICP (4180 K) was less than that of an Ar ICP (5570 K).     

Dissolution of Al-Fe materials and analysis by inductively coupled plasma – atomic emission spectrometry

A technique was developed for the dissolution of Al-Fe materials containing difficult to dissolve Al₂O₃. The developed procedure uses HCl and HNO₃ for initial sample attack followed by digestion with a mixture of H₃PO₄ and H₂SO₄ at 200 °C. This procedure was employe to dissolve Al-Fe material samples before the determination of Al and Fe. Minor and trace elements (B, Cr, Cu, Mo, Si, Zr) were determined after dissolution in HCl and HNO₃. Results of a round robin study verified the procedure accuracy. The developed methods have the required accuracy and precision to be used as a quality control procedure for Al-Fe materials analysis. Received: 9 February 1998 / Revised: 1 April 1998 / Accepted: 4 April 1998     

Direct analysis of tantalum powders by electrothermal vaporization inductively coupled plasma atomic emission spectrometry

A direct inductively coupled plasma atomic emission method for the determination of Ag, Al, As, Ca, Cd, Co, Cu, Fe, Ga, K, Li, Mg, Na and Pb in high-purity tantalum powders has been developed. The electrothermal vaporization technique using a modified longitudinally-heated Grün-ETAAS furnace with sample introduction on a platform and an automated sampling workstation provided the possibility of in situ analyte-matrix separation, freedom of blank, and applicability to routine analysis. Hard- and software were modified to allow signal recording and data processing independent of the spectrometer software. The extent of spectral interferences by Ta-emission at the analyte wavelengths used was determined and the analyte signals of each sample run were automatically corrected. Limits of detection ranging from 5 ng/g (Ag, Cu) to 250 ng/g (K, Pb) were obtained using optimized furnace and spectrometer conditions. The method was applied to the analysis of two tantalum samples and the results for Cu, Fe, K, Mg and Na were compared with those obtained by liquid and solid-samping ETAAS, showing satisfactory agreement.     

Dissolution of Al-Fe materials and analysis by inductively coupled plasma – atomic emission spectrometry

A technique was developed for the dissolution of Al-Fe materials containing difficult to dissolve Al₂O₃. The developed procedure uses HCl and HNO₃ for initial sample attack followed by digestion with a mixture of H₃PO₄ and H₂SO₄ at 200?°C. This procedure was employe to dissolve Al-Fe material samples before the determination of Al and Fe. Minor and trace elements (B, Cr, Cu, Mo, Si, Zr) were determined after dissolution in HCl and HNO₃. Results of a round robin study verified the procedure accuracy. The developed methods have the required accuracy and precision to be used as a quality control procedure for Al-Fe materials analysis.     

Quality of calibration in inductively coupled plasma atomic emission spectrometry

Calibration is a crucial step during the whole analytical process. A procedure is suggested to assess the quality of linear regression used for the calibration graph, based on the use of confidence limits for the concentration, as the regression coefficient is not appropriate for this purpose. This procedure has been applied to inductively coupled plasma atomic emission spectrometry. It indicates that the use of only three standards should be discouraged because of unacceptably high confidence limits for the concentration. Moreover, use of weighted regression is more adequate in performing the least squares method and provides more constant confidence limits over the concentration range used to construct the calibration graph. This procedure could be easily added to any commercially available ICP system software.     

Determination of phosphorus in fertilizers by inductively coupled plasma atomic emission spectrometry

An inductively coupled plasma atomic emission spectrometry (ICP-AES) method was developed for the determination of phosphorus in fertilizers. Total phosphorus, direct extraction available phosphorus (EDTA), and water-soluble phosphorus, reported as phosphorus pentoxide (P205), in 15 Magruder check fertilizers were measured by ICP-AES, and the results were compared with those obtained by the AOAC official method. Five analytical wavelengths of phosphorus, 177.499, 178.287, 213.618, 214.914, and 253.565 nm, were tested for the determination of phosphorus in fertilizers, and their detection limits were obtained. Acid effects of perchloric acid and possible matrix effects of aluminum, calcium, magnesium, potassium, and sodium were negligible for phosphorus determination. Wavelength 213.618 nm was the best analytical wavelength for phosphorus determination by all 3 sample preparation methods for the selected Magruder fertilizers. The results demonstrated that the accuracy and precision of the ICP-AES method were comparable with those of the official methods.     

Carbon-related matrix effects in inductively coupled plasma atomic emission spectrometry

In Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), it has been observed that the emission intensity of some atomic lines is enhanced or depressed by the presence of carbon in the matrix. The goal of this work was to investigate the origin and magnitude of the carbon-related matrix effects in ICP-AES. To this end, the influence of the carbon concentration and source (i.e. glycerol, citric acid and potassium hydrogen phthalate), the experimental conditions and sample introduction system on the aerosol characteristics and transport, plasma excitation conditions and the emission intensity of several atomic and ionic lines of a total of 15 elements has been studied. Results indicate that carbon related matrix effects do not depend on the carbon source and they become more severe when the amount of carbon loaded into the plasma increases, i.e., when using: (i) carbon concentrations higher than 5 g L^− 1; (ii) high sample uptake rates; and (iii) efficient sample introduction systems. Thus, when introducing carbon into the plasma, the emission intensity of atomic lines with excitation energies below 6 eV is depressed (up to 15%) whereas the emission intensity of atomic lines of higher excitation energies (i.e. As and Se) are enhanced (up to 30%). The emission intensity of the ionic lines is not affected by the presence of carbon. The origin of the carbon-related interferences on the emission intensity of atomic lines is related to changes in the line excitation mechanism since the carbon containing solutions show the same aerosol characteristics and transport efficiencies as the corresponding aqueous solutions. Based on the previous findings, a calibration approach for the accurate determination of Se in a Se-enriched yeast certified material (SELM-1) has been proposed.     

电感耦合等离子体原子发射光谱法测定高温合金中低含量钇

建立电感耦合等离子体原子发射光谱法测定高温合金中低含量钇的方法。采用盐酸、硝酸、氢氟酸溶解样品,在优化的仪器条件下,采用基体匹配法配制系列标准工作溶液,选择分析线为360.073 nm。钇的含量在0.0005%~0.050%范围内与光谱强度具有良好的线性关系,相关系数为0.99999,检出限为0.000003%。该方法测定结果的相对标准偏差不大于6.0%(n=8),加标回收率为90.0%~104.0%。该方法简便、快速、准确,可用于高温合金中低含量钇的测定。     

Determination of the ZnGeP2 composition by inductively coupled plasma atomic emission spectrometry

A procedure employing inductively coupled plasma atomic emission spectroscopy has been developed for the precise determination of the composition of Zn_{1 + x}Ge_{1 + x}P_{2 + x} alloys after their autoclave digestion. An optimal composition of the acid mixture has been chosen and the conditions preventing element losses in the digestion process have been found. To minimize the error of the developed procedure, the optimal concentration of Zn, Ge, and P in the analytes was found by calculating the results of analysis as atomic ratios Zn : Ge and P : Ge. The accuracy of the developed procedure was confirmed by the standard addition method and the comparison of the results with the results of an independent method. The relative standard deviation of the determination of atomic ratios was 0. 7–2.0%.     

电感耦合等离子体原子发射光谱（ICP-AES）法测定铁矿石中钒

建立了电感耦合等离子体原子发射光谱(ICP-AES)法测定铁矿石中钒含量的分析方法。采用盐酸、硝酸、氢氟酸、高氯酸分解试样,不溶物残渣碱熔融回收,稀盐酸溶解盐类的方式对样品进行分解。对仪器的主要工作参数和分析谱线进行了选择,讨论了基体和共存元素的干扰,以及溶解酸和熔剂等条件实验,确立了最佳分析条件。按实验方法对铁矿石标准样品和试样中钒量进行测定,测定值与标准值或其它方法的认定值基本一致,相对标准偏差RSD<6.5%。     

Analysis of molybdenum oxide by inductively coupled plasma atomic emission and mass spectrometry

Procedures for the analysis of molybdenum oxide by of inductively coupled plasma atomic emission spectroscopy (ICP-AES) and mass spectrometry (ICP-MS) are proposed on the basis of preliminary extraction separation of molybdenum from impurity elements. To separate 39 impurity elements (Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, Cr, Mn, Fe, Co, Ni, Zn, Ga, Rb, Sr, Y, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Pb, Bi, Th, and U), the extraction of molybdenum from hydrochloric acid solutions using 5-n-pentylthio-8-hydroxyquinoline was used. The capacities of both methods ICP-AES and ICP-MS in the analysis of molybdenum oxide analysis were examined without the removal of the matrix and after the extraction separation of molybdenum.     

电感耦合等离子体原子发射光谱法测定钛合金中锆

建立电感耦合等离子体原子发射光谱法(ICP-AES)测定钛合金中锆元素的含量。采用盐酸-氢氟酸-硝酸溶解钛合金样品,选择357.247 nm为锆的分析谱线,通过基体匹配法消除基体钛的干扰,以电感耦合等离子体原子发射光谱法测定钛合金中锆的含量。锆的质量分数在0%~0.4%范围内与光谱强度呈良好的线性关系,相关系数大于0.999,定量下限为0.21%。测定结果的相对标准偏差小于2%(n=11),样品加标回收率为99.0%~102.7%。该方法快速、准确,能够满足实际生产中钛合金样品的测定要求。     

Determination of uranium in organic solutions by inductively coupled plasma atomic emission spectrometry

The determination of uranium in organic solutions by inductively coupled plasma atomic emission spectrometry is reported. The conditions for achieving plasma stability were determined as well as the optimum conditions (RF power, observation height and argon flow) of a spectrometer for analysis of U(II) 367.007 nm in three organic solvents, xylene, kerosine and benzene. The effects of RF power and observation height on signal-to-back-ground ratio and the detection limits are considered. Spectral interferences due to CN band are discussed.A part of this work was presented at the Second Karlsruhe International Conference on Analytical Chemistry in Nuclear Technology Karlsruhe, FRG, June 5–9, 1989.     

Determination of boron in boron-alloyed steels by inductively coupled plasma atomic emission spectrometry

An inductively coupled plasma atomic emission spectrometry (ICP-AES) procedure has been developed and examined for the determination of boron content (0.01 up to about 2% B) in boron-alloyed steels such as POLDI ATA BOR (65% Fe, 19%Cr, 12% Ni, 1.5% Mn, 1% B), POLDI ATA BOR EXTRA (62% Fe, 18% Cr, 13% Ni, 2.5% Mo, 1.5% Mn, 1% B) and POLDI ATA BOR-R (75% Fe, 18% Cr, 3.5% Ti, 1.8% B). The steel sample is dissolved with a mixture of hydrochloric, nitric, sulfuric and phosphoric acids in a quartz vessel. Borides of alloyed metals, especially of iron and chromium, are quantitatively decomposed. The presence of phosphoric acid in a sample solution reduces the volatility of boric acid with water vapour.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria