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The elemental and crystalline phase compositions of fly ash collected before and after spraying of the ash with slaked lime (first and second fly ash) and the bottom ash of municipal solid waste collected at an incineration plant were analyzed using powder briquette by X-ray fluorescence spectrometry and Rietveld refinement by X-ray diffraction. The crystalline and amorphous phase contents were quantified by adding 10% corundum as an internal standard. In the first fly ash, SiO2, Cl, and CaO were the main components, and several thousand ppm (μg/g) of Zn and Pb were detected. Anhydrite, gehlenite, and amorphous phases were the main phases in the first fly ash samples. The components of the first fly ash originated exclusively from the incineration of municipal solid waste in a furnace. The crystal morphologies of the heavy elements in the ash samples were estimated by determining the correlations among the concentrations of all the elements. The heavy elements in the bottom ash showed no strong correlations with other elements; therefore, the heavy elements in the bottom ash were present in an amorphous phase.

The chemical states of heavy metals and radioactive Cs were estimated in fly ash sampled at Fukushima prefecture, Japan. Estimating the speciation of incinerator fly ash is important to ensure an appropriate and efficient management of fly ash generated from disaster-related waste. In this study, fly ash collected at a waste incineration facility in Fukushima prefecture was treated using a sequential extraction test. The test results indicated that the solubility behavior of radioactive Cs was similar to that of NaCl and KCl, and approximately 60% of radioactive Cs was included as water-soluble chloride compounds in the fly ash sample. Most heavy metals eluted in three fractions, in the extraction steps for carbonate-bound, free oxide, and bound to organic matter species. The chemical states of elements in the three non-water-soluble fractions and residue showed minimal elution into the environment. Therefore, most heavy metals in the fly ash exhibited minimal elution into the environment.

Six crystalline phases (anhydrite, calcite, gehlenite, halite, quartz, and sylvite) and the amorphous phase in fly ash of municipal solid waste (MSW) were quantified using Rietveld refinement of X-ray diffraction data. Corundum was used as an internal standard for the determination of amorphous phase. Gehlenite was synthesized by the solid-phase method to obtain the pure material for calibration standard. Quantitative values of 4.8, 5.1, 12.3, 9.3, 1.3, and 7.1 mass% for anhydrite, calcite, gehlenite, halite, quartz, and sylvite, respectively, were obtained by Rietveld refinement, in agreement with those obtained using the external standard and standard addition methods. Relative standard deviations (n = 5) of each crystalline phase were 1.6–63%. Monthly variations of crystalline phases of MSW fly ash were observed over a year (2008–2009). High correlation (R = 0.8068) was observed between the concentrations of halite and sylvite, which were derived from kitchen wastes such as vegetables and seasonings. Conspicuous concentrations of calcite and quartz were each observed once at June and December, respectively. Rietveld refinement was applicable as a quantitative method for the determination of MSW fly ash composition profile.

X-ray fluorescence spectrometry using the "standardless" fundamental parameter method has been studied for the whole elemental analysis of magnesium alloys. Twelve major elements were determined: Mg, Al, Si, Ca, Mn, Fe, Ni, Cu, Zn, Ag, Sn and Pb. The specimens used were over 30 mm in diameter and greater than 10 mm thick to determine Sn Kα which has the largest analyzing depth (9 mm) through the alloy samples. The surfaces of the specimens were polished with fine alumina abrasive paper (#240) to remove the oxide layer and to avoid the influence of any surface roughness variation on the intensities of Mg Kα, Al Kα and Si Kα which have smaller analyzing depths. The total quantitative values of the 12 elements, determined by the FP calculation, were normalized to 100 mass%. The analytical values obtained by this method were comparable to those obtained by the conventional calibration curves method. The relative standard deviations were 6.6% for 0.0014 mass% of Ni, and 0.005% for 93.82 mass% of Mg in AZ91 series Mg alloys. The validation results of the proposed method for 12 elements were successful for the five CRMs tested.

After the Fukushima Daiichi-Nuclear Power Plant accident, environmental recovery was a major issue because a considerable amount of municipal solid waste incineration (MSWI) fly ash was highly contaminated with radioactive cesium. To the best of our knowledge, only a few studies have evaluated the detailed physicochemical properties of radioactive cesium in MSWI fly ash to propose an effective method for the solidification and reuse of MSWI fly ash. In this study, MSWI fly ash was sampled in Fukushima Prefecture. The physicochemical properties of radioactive cesium in MSWI fly ash were evaluated by particle size classification (less than 25, 25–45, 45–100, 100–300, 300–500, and greater than 500 μm) and the Japanese leaching test No. 13 called “JLT-13”. These results obtained from the classification of fly ash indicated that the activity concentration of radioactive cesium and the content of the coexisting matter (i.e., chloride and potassium) temporarily change in response to the particle size of fly ash. X-ray diffraction results indicated that water-soluble radioactive cesium exists as CsCl because of the cooling process and that insoluble cesium is bound to the inner sphere of amorphous matter. These results indicated that the distribution of radioactive cesium depends on the characteristics of MSWI fly ash.

A bonding method utilizing redox reactions of metallic oxide microparticles achieves metal-to-metal bonding in air, which can be alternative to lead-rich high-melting point solder. However, it is known that the degree of the reduction of metallic oxide microparticles have an influence on the joint strength using this bonding method. In this paper, the reduction behavior of CuO paste and its effect on Cu-to-Cu joints were investigated through simultaneous microstructure-related x-ray diffraction and differential scanning calorimetry measurements. The CuO microparticles in the paste were gradually reduced to submicron Cu2O particles at 210–250°C. Subsequently, Cu nanoparticles were generated instantaneously at 300–315°C. There was a marked difference in the strengths of the joints formed at 300°C and 350°C. Thus, the Cu nanoparticles play a critical role in sintering-based bonding using CuO paste. Furthermore, once the Cu nanoparticles have formed, the joint strength increases with higher bonding temperature (from 350°C to 500°C) and pressure (5–15 MPa), which can exceed the strength of Pb-5Sn solder at higher temperature and pressure.

Gamma-ray (GR) logging measures naturally occurring gamma radiation in strata, and is a widely used method for reservoir characterization. The objectives of this study are to identify the source of total GR, and to discuss criteria for reasonable shale evaluation by the combined use of sediment core and GR logging analysis using a case study of the CO 2 storage aquifer at the Nagaoka site in Japan. The aquifer is comprised of shallow-marine siliciclastic deltaic deposits characterized by prodelta to delta front facies. The profile of total GR output is consistent with that of mud content, suggesting that the main source of GR can be attributed to minerals in the mud fraction. Prior to comparison of the radioactive elements measured by spectral gamma-ray (SGR) logging and elements from core analysis with total GR, elements were transformed to centered log-ratios to remove constant-sum constraints. Evaluation of the total GR profile with radioactive elements from SGR logging indicates that the distribution of thorium (Th) exhibits a high contrast between prodelta and delta front deposits. Th content has a significant positive correlation with total GR, implying that Th-bearing minerals mostly appear in fine-grained fraction. Conversely, the distribution of potassium (K) has a significant negative correlation with total GR, implying that K-bearing minerals appear in coarse-grained fraction. Based on geochemical analysis of the sediment core, minerals composed of Mg, Ti, Fe, Zr, and Th are likely to be radioactive carriers in the fine-grained fraction, and those containing Na, Al, Si, K, Rb, and Sr are considered to be the radioactive carriers in the coarse-grained fraction. The former can be attributed to detrital zircon grains and clay minerals, including smectite and chlorite, which contain or adsorb the radioactive Th, and the latter can be attributed to K-feldspar. The dispersion diagram between total GR and radioactive elements at observation wells emphasizes the differences in the endmembers of total GR between the two depositional sequences. The estimated shale volume is concordant with measured values if we select the endmembers at each depositional sequence. This means that the endmembers should be selected independently for each depositional sequence to enhance the reliability of shale evaluation. For improving shale evaluation, the combined use of GR logging and detailed core analysis in terms of sedimentology and geochemistry appears to be effective for reliably assessing shale volume in the target strata.

A preparation method of arsenic-containing white rice grains as calibration standards was developed for the X-ray fluorescence (XRF) analysis of arsenic in rice grains. Calibration standards were prepared by adding 10 g of white rice grains (from Japan) to 100 ml methanol-containing dimethylarsinic acid corresponding to 2–100 µg arsenic. The mixture was heated, dried at 150 °C, cooled to room temperature, and then stored in a silica gel desiccator. A total of 5.0 g of each calibration standard was packed into a polyethylene cup (32 mm internal diameter and 23 mm height) covered with a 6-µm-thick polypropylene film and then analyzed by wavelength-dispersive XRF spectrometry. The calibration curve for arsenic obtained from the white rice grains containing arsenic showed good linearity over a concentration range of 0.21–5.00 mg kg−1 arsenic. The limit of detection of arsenic was 0.080 mg kg−1. To check the reliability of the XRF method, the concentrations of arsenic in six samples of grain cereals and two samples of flour were compared with those obtained by atomic absorption spectrometry after acid decomposition. The values obtained by both analytical methods showed good agreement. Copyright © 2016 John Wiley & Sons, Ltd.

Soluble and insoluble radioactive cesium in municipal solid waste incineration fly ash were analyzed by X-ray diffraction and gamma-ray spectrometry. A total of 60% of soluble radioactive cesium was determined using the Tessier extraction method, and it was almost same extraction rate with Japanese leaching test No.13. In addition, chloride compounds such as halite (NaCl) and sylvite (KCl) showed same behavior with soluble radioactive cesium, therefore, soluble radioactive cesium existed as a chloride (CsCl) with water solubility characteristics. Almost insoluble radioactive cesium trapped into silicate of crystalline phase or amorphous phase was eluted by hydrogen fluoride treatment. Radioactive 137Cs was released in three stages by heating treatment (untreated - 400 °C, 600 °C–800 °C, and 800 °C–1000 °C) according to decreasing amorphous content. The relationship between the concentrations of radioactive 137Cs and amorphous phase exhibited good linearity (R = 0.9278). Insoluble radioactive 137Cs was contained in inner part of the amorphous phase, and free radioactive cesium was determined from the concentration of the amorphous phase.

The radioactive nuclides in the incinerator fly ashes from municipal solid waste sampled in June 2006 were analyzed with γ-ray spectrometry. The incinerator ashes were collected in northern Kyushu, Japan. Potassium-40, 137Cs, 210Pb, 226Ra, 228Ra and 228Th were identified and quantified in the γ-ray spectra of fly ash. Gamma-ray spectrometry was combined with a modified sequential extraction procedure based on the Tessier method used for the analysis of radioactive nuclides in fly ash. The crystalline phases and the elemental composition of fly ash were determined by using powder X-ray diffractometry and X-ray fluorescence spectrometry. After sequential extraction, most of 40K and 137Cs and part of 210Pb mainly existed as water-soluble salts, while 226Ra, 228Ra and 228Th were enriched in the residual material of fly ash, especially depending on basicity (Ca/Si ratio) of MSW. Although, 210Pb and stable Pb are isotopes of each other, the distribution of 210Pb is different from that of stable Pb. The differences in the chemical states of 210Pb and stable Pb might result from their distinct origins; 210Pb originates from the decay of 222Rn and is associated with aerosols, whereas stable Pb is mainly derived from relatively inert chemical forms.

A laboratory-scale X-ray diffractometer for obtaining high X-ray intensity data was developed. The apparatus, equipped with 600 W CuKα radiation with a Ni filter, incorporates technology that dramatically improves the quality of X-ray diffraction. The system comprises of a low-noise one-dimensional silicon strip detector, a variable slit, and a goniometer with a radius as small as 150 mm. A variable knife edge was used as a countermeasure for unwanted scattering, particularly in the low angle range. With this system, cement may be analyzed within 5 min. NIST 2686 standard reference material was analyzed using the newly developed diffractometer, and the quantitative analysis results for the major phases are in agreement with the certified values of the reference material.

A direct analysis method combining an iminodiacetate extraction disk (IED) with graphite furnace atomic absorption spectrometry was developed for the determination of Co, Ni, Cu, Cd, Sn, Pb, and Bi at sub-ppb levels in water. A 100 mL water sample was adjusted to pH 5.6 with nitric acid and a 1 mol?L–1 ammonium acetate solution, and then passed through an IED (diameter, 47 mm; effective filtering diameter, 35 mm) at a flow rate of 80 - 100 mL?min–1 to preconcentrate seven analytes. The IED was dried at 100?C for 20 min in an electric oven, and 110 - 145 small disks, each 2 mm in diameter, were punched out from the IED. A small disk was introduced into the graphite furnace and atomized according to a heating program. For Cd, Sn, Pb, and Bi measurements, Pd was used as a chemical modifier to enhance the absorbances. Calibration was performed using aqueous standard solutions. The detection limits, corresponding to three times the standard deviation (n = 5) of the blank values, were 0.092 μg·L–1 for Co, 0.12 μg·L–1 for Ni, 0.40 μg·L–1 for Cu, 0.077 μg·L–1 for Cd, 0.92 μg·L–1 for Sn, 0.61 μg·L–1 for Pb, and 0.80 μg·L–1 for Bi with an enrichment factor of 140 using a 100-mL water sample. A spike test for the seven analytes in tap water, rainwater, river water, and mineral drinking water showed quantitative recoveries (93% - 108%).

都市ごみ焼却飛灰中の主成分12成分と微量6成分を，粉末ブリケット法を用いた蛍光X線法で分析した．焼却飛灰をボールミルで80分間粉砕すれば，各成分の蛍光X線強度の相対標準偏差は3.2％ になり，均質な試料が得られた．そのときのモード粒径は12 μmであった．検量線用試料は，各成分を含む試薬をV型混合機で80分間混合してから，混合物をボールミルで20分間粉砕するか，試薬を2時間手混合して作製した．揮発性元素のCl，Brは，管球の出力を1.0 kW（50 kV - 20 mA）以下にすることで繰り返し分析を可能とした．石炭焼却飛灰標準物質（NIST 1633b）を用いて検量線を評価したところ，主成分の分析値は認証値とよく一致した．A，Bの飛灰では，Al2O3，SiO2，Cl，CaOの濃度が高く，C飛灰はNa2O，SO4，Cl，K2Oの濃度が高かった．3つの飛灰には微量成分としてZnとPbが数千ppm含まれていた．

Glass bead/x-ray fluorescence spectrometry of the sludge incineration ashes generated in sewage processing was developed for the determination of ten major components (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, Fe2O3) and five minor elements (Zn, Cu, Cr, As, Pb). Sewage sludge ashes consisted of rock-forming minerals and phosphate crystals that had been used for phosphorus removal. Ash samples were melted and molded with lithium tetraborate to 35 mm diameter glass disks in a Pt–Au crucible. Analytical results of ten major components and five minor elements agreed well with the recommended values of a phosphate rock standard reference material (NIST SRM 694). Elemental compositions of sewage sludge ash from seven sewage-processing plants in Japan were determined using this method. Concentrations of Fe2O3, SiO2, and CaO, along with loss of ignition in sewage sludge ash mutually differed among the sewage-processing plant products. Seasonal variations in concentrations of ten major components and five minor components of ash samples produced from October 2001 to September 2002 were determined using the proposed method. Concentrations of SiO2increased with the inflow of gravel by rainfall, thereby decreasing concentrations of P2O5 originating from excreta and microorganisms. Copyright © 2008 John Wiley & Sons, Ltd.

X-ray fluorescence (XRF) analyses of 13 major and 5 minor components in alkali-washed fly ash of municipal solid waste were developed using powder briquette method. Fly ash samples were ground for 80 min using a ball mill to prepare reproducible powder briquette. The resultant particles had 12-µm modal diameter and gave good reproducibility (3.2%). Calibration curves for analyses of 13 major and 5 minor elements required 16 reagents containing 18 analytes. They were ground for 20 min by ball milling after 80-min mixing with a V-type mixing machine or 2-h manual mixing using an alumina mortar. Lower limits of detection corresponding to 3 times the standard deviation (n = 6) for blank measurements were: Na2O, 23 ppm; MgO, 22 ppm; Al2O3, 24 ppm; SiO2, 21 ppm; P2O5, 3.0 ppm; SO4, 3.1 ppm; Cl, 232 ppm; K2O, 51 ppm; CaO, 26 ppm; TiO2, 32 ppm; Cr, 6.3 ppm; MnO, 7.2 ppm; Fe2O3, 18 ppm; Ni, 5.3 ppm; Cu, 4.7 ppm; Zn, 5.4 ppm; Br, 4.7 ppm; and Pb, 4.6 ppm. This method was applied to analyses of 13 major and 5 minor elements in fly ash samples, which mainly consisted of Al2O3, SiO2, Cl, and CaO. Several thousand parts per million of Zn and Pb were included in most fly ash samples; Cl and Br were analyzed though their volatile characteristics. Copyright © 2008 John Wiley & Sons, Ltd.

Organic analysis and inorganic analysis are generally based on different physical principles, and for this reason it is difficult to analyze resins and pigments simultaneously. For these reasons, we have performed Py-GC/MS measurements of red-, yellow-, and green-colored lacquer films applied to lacquerware items to assess the feasibility of simultaneously detecting resin ingredients together with certain pigments. We have also compared our findings to the results of SEM-EDS, X-ray fluorescence spectrometry (XRF), and X-ray diffractometry (XRD) measurements. XRD analysis yielded molecular-level information (information on binding states) regarding mercury (Hg) and iron (Fe); however, the information obtained for arsenic (As) and sulfur (S) was insufficient. In contrast, Py-GC/MS analyses simultaneously yielded molecular-level information on arsenic (As) and sulfur (S) together with detection of the primary ingredients of the lacquer. For this reason, it shows that several pieces of information is provided easily and quickly when the colored lacquer cultural heritage is measured using the Py-GC/MS method.

Radioactive nuclides in the incinerator ashes of municipal solid wastes were determined by γ-ray spectrometry before and after the accident at the Fukushima nuclear power plant (March 11, 2011). Incinerator ash samples were collected in northern Kyushu, Japan, which is located approximately 1200 km west-southwest (WSW) of the Fukushima nuclear power plant, from April 2006 to March 2007 and from March 2011 to October 2011. (40)K, (137)Cs, (208)Tl, (212)Pb, (214)Pb, (212)Bi, (214)Bi, and (228)Ac were identified in the ashes before the accident (~February 2011) and (134)Cs was identified along with these eight nuclides in the ashes after the accident (March 2011~). A sequential extraction procedure based on a modified Tessier method with added water extraction was used for 1st fly ash sampled in August 2011 because the highest activity concentrations of (134)Cs and (137)Cs were observed for this sample. The speciation of radioactive nuclides in the fly ash was achieved by γ-ray spectrometry and powder X-ray diffractometry for the extraction residues. Little variation was observed in the distribution of the chemical forms of (134)Cs and (137)Cs in 1st fly ash of municipal solid waste; one half of (134)Cs existed as water soluble salts and the other half as carbonate compounds, whereas 75% of (137)Cs existed as water soluble salts with the remainder as carbonates(10%) and sulfides (15%). These results show that 88% of the total radioactive Cs existed in water soluble and ion extractive forms and might be at risk for elution and diffusion with rain and wind.

Chemical interaction of Portland cement with supercritical CO2 along the cement - sandstone interface was investigated. To model a well in a CO2 geological storage site, we prepared the well composite sample consisting of casing, Portland cement and sandstone. Using this sample, we conducted batch experiments in a laboratory scale to estimate the chemical interactions of CO2 under a reservoir condition (10 MPa, 50 °C, 0.5 M NaCl). The elemental and crystal phase analysis of CO2 exposed samples were carried out by SEM-EDS and μ-XRD. In the cement region, a carbonation zone of the cement occurred adjacent to the sandstone with both samples exposed to CO2. From the results of SEM-EDS analysis, it was found that Ca concentration in the carbonation zone increased about 20% in comparison to that in the unaltered cement zone while concentration of Mg, Si, S at the carbonation zone decreased. Crystal phase at the carbonation zone were predominantly CaCO3 (calcite, aragonite and vaterite) and trace Friedel's salt. In addition, CaCO3 were sparsely precipitated in the pore spaces of sandstone along the sandstone-cement interface. These results indicate that the formation of carbonation layer provides as an effective barrier to further CO2 attack.