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Fused borate glass beads were used for the determination of 42 components (Na, Mg, Al, Si, P, K, Ca, Sc, Ti, V, Cr, Mn, Fe Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, Nb, Sn, Cs, Ba, La, Ce, Pr, Nd, Sm, Gd, Dy, Er, Yb, Hf, Ta, W, Pb, Th, and U) in felsic rocks using x‐ray fluorescence spectrometry (XRF). Low‐dilution glass beads with 1:1 sample‐to‐flux ratios (called 1:1 glass beads) were prepared using the double‐fusing method to measure Sc, Sn, Cs, Hf, Ta, and rare earth elements. Double‐fusing, which uses two heating stages with intervening cooling to room temperature, was used to prepare homogeneous 1:1 glass beads. Pulverized rock samples of less than 20 µm modal diameter enabled us to prepare homogeneous 1:1, 1:2, and 1:10 glass beads. The glass bead thickness was set as constant because the fluorescent x‐ray intensity of heavier elements, such as Rb, Sr, Y, and Zr, was influenced by thickness of 1:10 glass beads. Mutual interference of the nine analytical lines, V Kα, Cr Kα, Y Kα, Zr Kα, Nb Kα, Ba Lα, Ce Lα, Er Lα, and Yb Lα, was corrected using the intensities of Ti Kα, V Kα, Rb Kα, Sr Kα, Y Kα, Rb Kα, Ba Lα, Zr Kα, and Ni Kβ, corresponding to each overlap. Calibration curves of the 42 components showed good linearity (coefficient of determination, r = 0.991–1.000). The calibration ranges, indicating lower and upper limits of detection, were 1.6–58 to 0.03–7.6 mass ppm for the major elements (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, and Fe2O3) in 1:10 glass beads, 0.2–0.5 to 50–100 mass ppm for Rb, Sr, Y, and Zr in 1:10 glass beads, 0.3–6.0 to 20–230 mass ppm for minor elements (V, Cr, Co, Ni, Cu, Zn, Ga, As, Nb, Ba, W, Pb, Th, and U) in 1:2 glass beads, and 0.7–8.9 to 20–220 mass ppm for trace elements (Sc, Sn, Cs, Hf, Ta, and rare earth elements) in 1:1 glass beads. Using this method, we determined 42 components in two granites from Japan, weathered granite, obsidian, and rhyolite. Copyright © 2007 John Wiley & Sons, Ltd.

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in igneous rocks were assayed with fused lithium borate glass beads using X-ray fluorescence spectrometry. Low dilution glass beads, which had a 1:1 sample-to-flux ratio, were prepared for determination of rare earth elements. Complete vitrification of 1:1 mixture required heating twice at 1200˚C with agitation. Extra pure reagents containing determinants were used for calibrating standards instead of the rock standard. The calibration curves of the 23 elements showed good linearity. Furthermore, the lower limits of detection corresponding to three times the standard deviation for blank measurements were 26 mass ppm for Na2O, 6.7 for MgO, 4.5 for Al2O3, 4.5 for SiO2, 18 for P2O5, 1.1 for K2O, 4.0 for CaO, 3.9 for TiO2, 1.6 for MnO, 0.8 for Fe2O3, 0.5 for Rb, 0.2 for Sr, 0.4 for Y, 0.5 for Zr, 3.3 for La, 6.5 for Ce, 2.7 for Pr, 2.1 for Nd, 1.7 for Sm, 0.7 for Gd, 2.7 for Dy, 0.5 for Th, and 0.6 for U. Using the present method, we determined the contents of these 23 elements in four rhyolitic and granitic rocks from Japan.

Plasma activated water (PAW) containing reactive oxygen and nitrogen species (RONS) is of great interest for applications in the agricultural and food industries, where processing methods with large capacities and high energy-yields are required. In this work, we studied the differences between seven types of discharge schemes in terms of the production rates and concentration ratios of RONS using deionized water and tap water in comparison. We used N 2 and air as the feed gas with a variable admixture of water vapour. When O 2 was incorporated into the reaction system, the major products in the PAW became NO − 2 and NO − 3 , while small amounts of H 2 O 2 and NH + 4 were detected only in O 2 poor situations with water vapour. Of the major products, the condition of whether NO − 2 or NO − 3 becomes predominant is dependent on the extent of successive oxidation reactions from NO to NO 2 and NO 3 and the competing rates between gas phase reactions and dissolutions into water. In our tested discharge schemes, those with volumetric glow-like discharge structures produced NO − 3 rich PAW, while those with spark discharge structures over the water surface or in water were favourable for the production of NO − 2 rich PAW. In particular, a discharge scheme with a wire-in-nozzle structure operated in a spark-mode with a bubbling gas flow yielded PAW with the highest NO − 2 concentration, more than 70%, at a high energy-yield of 2 g kWh −1 . In the storage period, NO − 2 was converted into NO − 3 due to ionic reactions in aqueous solution, but the buffer action of tap water was observed to suppress the conversion for a fairly long period.Keywords: plasma activated water, reactive oxygen and nitrogen species, NO − 2 , NO − 3 , H 2 O 2 , NH + 4 , energy-yield

Quantitative analyses of Cr, As, Se, Cd, Hg, and Pb in soil were performed using wavelength dispersive X‐ray fluorescence (WDXRF) spectrometry with pressed powder pellet and loose powder methods. Standard soil samples containing hazardous metals were prepared by adding appropriate amounts of aqueous standards to base soils and then drying and homogenizing them. Base soil powders ground to less than 12.5 µm of modal particle size were Tachikawa loam, brown forest soil, and weathered granite containing 17.9, 9.43, and 3.49 mass% of Fe2O3, respectively. Analytical lines were CrKα, AsKα, SeKα, CdKα, HgLα, and PbLβ, with accompanying corrections for overlapping of SeKβ to PbLβ and PbLα to AsKα. Specimens for XRF analysis were prepared using powder pellets pressed to 23 mm internal diameter of an Al ring with 300 kgf cm−2, and loose powder in a 31 mm internal diameter polyethylene cup covered with 6‐µm thickness of polypropylene film. Calibration curves drawn using the proposed standards showed good linearity under 3000 mg kg−1 for the five metals, and 300 mg kg−1 for Hg. Corrections with Compton scattering for AsKα, SeKα, CdKα, HgLα, and PbLβ, and with background scattering for CrKα were effective and produced identical inclinations of calibration curves. CdKα having larger critical depth in the loose powder specimen showed merely smaller inclination of calibration curve than that of the pressed powder specimen because of optical shading. The spike test for five analytes showed good recovery for gravel soil and pumice soil. Copyright © 2009 John Wiley & Sons, Ltd.

The reaction mechanism of a manganese precursor, tris͑dipivaloylmethanato͒manganese ͓Mn͑DPM͒ 3 ͔, was investigated in liquid delivery metallorganic chemical vapor deposition ͑MOCVD͒ of manganese oxide films. The behavior of Mn͑DPM͒ 3 in the gas phase was analyzed under actual CVD conditions by in situ infrared absorption spectroscopy. The temperature dependence of the infrared absorption indicates that Mn͑DPM͒ 3 was decomposed in the gas phase under the actual deposition conditions. We discuss the correlation between the thermal decomposition of Mn͑DPM͒ 3 in the gas phase and film deposition of manganese oxides. When the substrate temperature is raised above 360°C, the deposition rate decreases, synchronized with the decrease of the infrared absorption by Mn͑DPM͒ 3 in the gas phase. The oxidation state of Mn in the deposited films was also investigated by highresolution X-ray fluorescence spectroscopy. No significant difference in the oxidation state of Mn is found between the deposited films and the starting source material, Mn͑DPM͒ 3 .Manganese-containing oxides have been receiving much attention due to their interesting physical and chemical properties and their related applications to rechargeable batteries, catalysts, sensors, and magnetic devices. Thin films of manganese-containing oxides have been synthesized by various deposition methods. From the viewpoint of practical use in device processes, metallorganic chemical vapor deposition ͑MOCVD͒ is regarded as one of the most promising techniques for the deposition of manganese-containing oxide films because of its excellent step coverage and good composition controllability. The MOCVD technique using liquid source delivery has the advantage of providing a stable and efficient supply of source materials. Although intensive work has been performed for process development, 1-3 the deposition chemistry is still not well understood in the liquid source MOCVD of manganese oxide films. In view of a lack of established guiding principles to control film quality, attempts to accumulate experimental data on gas-phase and surface reactions under actual CVD conditions are necessary to understand the film deposition mechanism. Recently, we have demonstrated that spectroscopic techniques such as in situ infrared absorption spectroscopy 4-10 and microdischarge optical emission spectroscopy 11,12 are useful for studying gas-phase reactions of various MOCVD precursors.In this work, in situ infrared absorption spectroscopy was employed under actual liquid delivery CVD conditions to understand gas-phase reactions of a manganese precursor, tris͑dipivaloylmetha-nato͒manganese ͓Mn͑DPM͒ 3 ,Mn͑C 11 H 19 O 2 ͒ 3 ͔. The chemical structure of Mn͑DPM͒ 3 is shown in Fig. 1. We observed the temperature dependence of the infrared absorbance and measured the deposition rate and atomic composition of the deposited films. The spectroscopic data on the gas-phase reactions, such as thermal decomposition and oxidation, were correlated with the characteristics of the deposited oxide films. Figur...