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Lithium-chromium-manganese oxides, LiMn x Cr 1-x O 2 (0 < x< 0.6), were synthesized as solid solutions by simple calcination of emulsion-dried powder precursor. The product was well crystallized to an α-NaFeO 2 structure (space group: R3m). By combination of Rietveld analysis of X-ray diffraction data and X-ray absorption near edge structure (XANES) techniques, the final product is considered to be [Li 1 ] oct 3a [Mn III x CrIII 1-x ] oct 3b [O 2 ] 6c (0 < x < 0.6). The prepared oxides were electrochemically active, and capacity as cathode materials for lithium-ion battery was improved with increasing Mn substitution amount.

This paper reviews recent trend in analytical approach in mineralogy based on the presentations at the micro symposium on mineral analysis at the annual meeting of the Mineralogical Society of Japan. There were 9 oral and 7 poster presentations, which included several new approaches such as XANES analysis of Ce in geochemically important samples, PIXIE analysis of fluid inclusion, mineralogical identification by EBSD as well as conventional approaches. The former approach emphasizes on application of new methodology while the latter one emphasizes scientific finding from specific samples of interest using well-established techniques. It is concluded that the advance of instrumental analytical techniques open a new door of the mineral Kingdom in both fields.

放射光蛍光X線を用いて, 動物プランクトンの一種であるシオミズツボワムシ (Brachionus plicatilis) 1個体に含まれる微量元素の2次元分析, 定量分析を行った. その結果, 4日齢単性生殖雌の2次元元素分布からは, 胃にFe, Zn, 生殖器にはFe, Zn, Cu, Ca, 頭部にMnが局所的に濃集していることが分かった. これらの元素は, 餌であるクロレラに含まれていることから, 餌を摂取することによりワムシ体内に蓄積されることがICP-MSの定量分析結果からも得られた. 放射光蛍光X線によるMn, Cu, Znの定量分析の結果は, 複数個体を用いて硝酸分解後ICP-MS測定により求めて平均化した値と同じ挙動を示した. 放射光を用いることで, ワムシ1個体の微量元素分析が可能であることが本研究により実証できた.

High-energy (116 keV) synchrotron radiation X-ray fluorescence analysis has for the first time been applied to the quantitative analysis of trace heavy elements of geological samples. Calibration c...

The layered molybdenum oxide Na0.9Mo2O4 was soft-chemically exfoliated into unilamellar nanosheets, and its layer-by-layer assembled films exhibited ohmic electrical conductivity.

The Zn-bearing beaverite of Sato et al. (2008) has been named ‘beaverite-(Zn)’ in accordance with the alunite supergroup nomenclature of Bayliss et al. (2010), and data for the mineral have been approved by the IMA-CNMNC. Beaverite-(Zn) occurs as a dark-brown secondary mineral in the hydrothermal Cu-Zn-Pb ore deposit of the Mikawa mine, Niigata Prefecture, Japan. Electron microprobe analysis gave an empirical formula of Pb0.95(Fe1.88Al0.10)(Zn0.83Cu0.03)(SO4)2[(OH)5.36O0.38] on the basis of S = 2. The Rietyeld analysis (Sato et al, 2008) indicated it to be trigonal, R3̄m, a = 7.3028(2), c = 17.0517(4) Å, V = 787.56(4) Å3.

Total reflection X-ray fluorescence analysis (TXRF) has been successfully used to determine trace amounts of Cisplatin platinum in biopsy samples. The minimum detection limit of Pt by TXRF analysis using monochromatic Mo Kα radiation with a LiF (200) crystal was 0.01ppm, and the minimum quantification limit was 0.1ppm for the biological samples. Biopsy tissues and blood serum samples were taken from patients with advanced bladder cancers. Variations of Pt concentration at tumor tissue and in blood serum of the patient with time were clarified for both types of samples. This study indicates that TXRF is a most suitable technique for the analysis of trace platinum in biopsy samples.

Synchrotron radiation-induced X-ray fluorescence (SR-XRF) analysis was applied to examine the distributions and chemical forms of trace titanium in samples of banded iron formations (BIFs) from the Hamersley area of Western Australia. SR-XRF imaging and XANES (X-ray absorption near edge structure) analysis showed that titanium-enriched layers in the BIFs contained two types of titanium compounds: Ti in silicate and titanium oxides. All the compounds were in the tetravalent state. The difference between the two types of compounds may reflect different origins: i.e., the oxide phase may be precipitated from the solutions and the silicate phase may come from clastic input of terrigenous origin. SEM observation revealed peculiar spherical aggregates that contained manganese carbonate, suggesting a possible relation to biological activity.

Spinel lithium manganese oxides LiMn 1.6 M 0.4 O 4 (M=Mn, Co, Cr, Ni) for the cathode materials of the lithium ion secondary batteries were studied by electron energy loss spectroscopy (EELS). The ELNES spectra at Mn L- and O K-edge of the extracted lithium or substituted to Mn 16d site with third cations were successfully obtained. Electrochemically deintercalated Li 1− x Mn 2 O 4 showed a chemical shift of both Mn L- and O K-edges to the higher energy side compared with those of the stoichiometric LiMn 2 O 4 indicating oxidation of Mn and O due to the electrochemical deintercalation of Li. Substitution of M for Mn (M=Co, Cr, Ni) also caused a similar spectral shift of Mn L- and O K-edges. These shifts suggest lowering of the energy levels of the inner atomic orbitals compared with that of LiMn 2 O 4 .

This study has revealed the advantages of the use of 116 keV X-rays as an excitation source of X-ray fluorescence (XRF) analyses. This technique is suitable for nondestructive multielemental analyses of heavy elements such as rare-earth elements. The lowest MDL value evaluated for the bulk analysis of a JG-1 standard reference sample (granite rock) was 0.1 p.p.m. for W for a 500 s measurement. The spectrum of standard glass samples of SRM612 demonstrated clearly resolved K-line peaks of more than 30 elements, including all the existing rare-earth elements, at 50 p.p.m. levels. The calibration curve for the determination of a rare-earth element shows a linear relation between the XRF intensity and concentrations from 10 to 0.03 ng. This powerful technique should be useful for nondestructive analyses of rare-earth and heavy elements in geological, geochemical and archaeological samples as well as industrial materials.

Chemical states and structural changes accompanying the electrochemical Li deintercalation of Li1−x(Mn, M)2O4 (M=Cr, Co, Ni) were studied by the in situ X-ray absorption fine structure (XAFS) technique. The X-ray absorption near-edge structures (XANES) of Mn and M as a function of x showed that the high voltage (∼5 V) in the cathode materials of an Li secondary battery is due to the oxidation of M3+ to M4+ (M=Cr, Co) and M2+ to M4+ (in the case of M=Ni), while the origin of the low voltage (3.9–4.3 V) can be ascribed to the oxidation of Mn3+ to Mn4+. The extended X-ray absorption fine structure (EXAFS) analysis of Li1−x(Mn,Ni)2O4 revealed that Ni2+ is oxidized to Ni4+ via the Ni3+ state with a Jahn–Teller distorted Ni3+–O octahedron.

Kozoite-(Nd), Nd(CO 3 )(OH), occurs in cavities and fissures of alkali olivine basalt exposed at Niikoba, Hizen-cho, Higashi Matsuura-gun, Saga Prefecture, Japan, in association with lanthanite-(Nd) and kimuraite-(Y). The crystal structure was refined by the Rietveld method in space group Pmcn; a = 4.9829(1), b = 8.5188(2), c = 7.2570(2) A, Z = 4 using powder diffraction data obtained by a combination of a Gandolfi camera and monochromatic synchrotron radiation. Kozoite-(Nd) is pale pinkish-purple to white with a vitreous to powdery luster. The calculated density is 4.77 g/cm 3 . It has high birefringence, α = 1.698(2), α = 1.780(5). The four strongest lines in the X-ray powder patterns [ d (A), I / I 0 , hkl ] are (4.29, 100, 110); (2.93, 89, 102); (2.33, 78, 131) and (2.06, 78, 221). Kozoite-(Nd) is the first naturally occurring RE(CO 3 )(OH) end-member in the ancylite group.

Synchrotron radiation-induced X–ray fluorescence (SR–XRF) and conventional X-ray fluorescence (XRF) analyses were applied to determine the distributions of iron, manganese, calcium, titanium, and silicon, and chemical forms of iron and trace manganese in three banded iron formation (BIF) samples. The XRF imagings on the weathered and altered BIF from the Cleaverville Formation (3. 3–3. 1 Gyr), Western Australia, showed redistributions of iron, calcium, and manganese with the disappearance of the primary bandings, while, in contrast, titanium preserved its primary depositional distribution. The XRF imagings on the BIF from the Hamersley Group (2. 5 Gyr), Western Australia, showed that manganese and titanium distribute originally at boundary region between the iron-rich mesoband and the silica-rich mesoband. The X-ray Absorption Near Edge Structure (XANES) analysis revealed that the chemical forms of manganese and iron well represent the rhythmic change of the bandings.

Effect of the elevated temperature and that of the lithium deintercalation on the structure of stoichiometric material LiMn 2 O 4 and lithium excess material Li(Mn 1.85 Li 0.15 )O 4 were investigated by in situ XAFS technique. The stoichiometric material showed capacity loss after charge–discharge cycles at 60°C and gave deformed XAFS spectra, while the lithium excess material showed resistance to the high-temperature cycling and gave a similar XAFS spectra to the non-heated material. The XAFS analysis suggests that high-temperature cycles caused structural disorder of LiMn 2 O 4 , but not that of Li(Mn 1.85 Li 0.15 )O 4 . Since the lithium excess material has good structural stability against the cycling at the elevated temperature, this material will be suitable for the cathode material of the commercial batteries.

Antarctic micrometeorites (AMMs) were found among the precipitated fine particles recovered from a water tank in the Dome Fuji Station. These AMMs had been contained in the recent fallen snow around the station. Initial processing of the precipitated particles revealed that they were dominated by natural and artificial terrestrial materials, thus a series of processes were developed to separate AMMs from terrestrial particles. The recovery rate of AMMs by the processes was approximately 45% in weight, which was determined from a weight ratio of recovered/accreted AMMs. The micro-morphology and major-element concentration of the recovered AMMs were characterized. They appear to have been heated upon atmospheric entry to varying temperatures and can be classified into two major types based on the degree of heating : (1) fine-grained, irregular-shaped, partial-melted micrometeorites with chondritic composition, and (2) total-melted spherical micrometeorites with chondritic composition except for volatile elements. A digital catalog for the AMMs identified in this study was established on the web site [URL : http : //dust. cc. gakushuin. ac. jp/], in which optical characteristics, high-resolution images, and chemical compositions of individual AMMs are presented. The AMMs listed in the catalog are the first Japanese collection of extraterrestrial dust. The criterion and techniques developed for the selection and initial analysis of AMMs are applicable for the dust samples that are being collected by the 39th Japanese Antarctic Research Expedition team.

An electrochemical cell was developed for the in situ transmission X–ray Absorption Fine Structure measurements of the charge/discharge process of the cathode materials of lithium secondary batteries, from which Li can be electrochemically deintercalated or intercalated. The dynamical structural behavior of Mn in Li(Mn 1.93 Li 0.07 )O 4 , and Li(Mn 1.85 Li 0.15 )O 4 as a function of both excess Li content and the Li deintercalation was revealed using the in situ cell. The analysis disclosed the coexistence of two MnO 6 –coordination polyhedra with different Mn–O distances for the Mn 3+ and Mn 4+ ions at the 16d site of the spinel structure. Because the charge–discharge process accompanies the oxidation–reduction of the Mn ions, this size difference causes an unfavorable lattice distortion for the electrode materials which can cause a loss of cell capacity after cyclic use of the cell. A partial substitution of Li for Mn will diminish this effect and will be favorable for the battery material.

Synchrotron radiation–induced X–ray fluorescence imaging is suitable for determining the distribution of trace elements in fish otoliths. The Sr/Ca ratio in an otolith is an indicator of salinity changes and can be used to clarify the migration history of the eel, a catadromous fish. The otoliths of eel collected from the Tone and Elbe rivers exhibited a typical catadromous pattern, i.e. birth and breeding occurred in the ocean, but the remainder of their lives was spent in fresh water. In contrast, eels from the East China Sea and North Sea exhibited an unusual sea–locking phenomenon, as they appear to have remained in marine habitats throughout their lives.

The fluorescence XAFS (X–ray absorption fine structure) technique using synchrotron radiation was applied to characterize zinc in the Hg–Zn, Cd–Zn, and Bi–Zn coprecipitates, and to elucidate the reaction mechanism of the coprecipitation of zinc from a strong acidic solution. Hg LII–, Cd K–, and Bi LIII–edge XAFS spectra suggested that the respective host materials of the coprecipitates listed above are metacinnabar (HgS), greenockite (CdS), and bismuthinite (Bi2S3) and that existence of zinc has not affected the local structure of the host metal sulfides in each system. On the other hand, the Zn K–edge XAFS spectra of each coprecipitate indicated that the chemical forms of zinc compounds are controlled by the crystal structure of the host sulfides.The shapes of the Zn K–XAFS spectra of the Hg–Zn and Cd–Zn coprecipitates showed a strong resemblance to those of crystalline standards ZnS, wurtzite and spharelite. It was suggested that the two coprecipitated phases (HgS, ZnS) and (CdS, ZnS) may form a solid solution in the Hg–Zn and Cd–Zn coprecipitates. The local structure around the zinc(II) ion in the Bi–Zn coprecipitate is the same as that around hexaaqua–zinc(II) ions, and adsorption of soluble ions or mechanical occlusion from the mother liquor is regarded as a driving force of coprecipitation in the Bi–Zn system.

Structural changes accompanying the electrochemical Li deintercalation of Li1−xNiO2and Li1−xCoO2were studied by the transmission X-ray absorption fine structure (XAFS) technique using anin situX-ray cell of original design. Our results revealed that the Jahn–Teller distortion of the Ni–O octahedra found in LiNiO2decreased as the Li ion was removed from the cathode. The observed X-ray absorption near-edge structures (XANES) of Li1−xNiO2and Li1−xCoO2as a function ofxare consistent with the phase transitions found by powder-diffraction studies. The Ni–O, Co–O, and Ni–Ni interatomic distances decreased almost linearly as the Li content decreased tox=0.8, while the Co–Co distance slightly decreased tox=0.5 and increased up tox=0.8. The local distortion of NiO6octahedra also decrease with increasingyin a Li(Ni1−y, Coy)O2solid solution.

The crystal structure of ammonioleucite was refined by a Rietveld analysis using X-ray diffraction data of the type specimen. The refinement with a space group I4l/a was converged at Rwp=12.12, Rp=9.39, RF=4.86, RB=7.71, and Re=2.55% with lattice parameters of a=13.2106(6) and c=13.7210(7) A. Ammonioleucite is isostructural with leucite. The (Si, Al)O4 tetrahedra form 4-, 6-, and 8-membered rings by sharing their apical oxygen atoms. The crystal structure consists of the three-dimensional framework of the rings of the tetrahedra. Ammonium ions are located in cavities in the framework. The (NH4)+ ions in these cavities are larger than the corresponding K+ ions in leucite, causing the cavities to be enlarged relative to those in leucite. Among the 4-, 6-, and 8-membered rings of (Si,Al)O4 tetrahedra, only the 8-membered rings have diameters large enough to allow the migration of exchangeable K+, (NH4)+ and Na+ ions.

Variations of electronic and local structures of Ni and Co in Li1 − xNiO2 and Li1 − xCoO2 as a function of x were clarified for the first time by in situ X-ray absorption fine structure analysis (XAFS). Chemical shifts of the X-ray absorption near edge sructure spectra of the Ni K-edge in Li1 − xNO2 as a function of x were continuous while an abrupt change was observed for the Co K-edge spectra of Li1 − xCoO. Radial structure functions obtained by Fourier-transform of the Ni K-edge EXAFS of LiNiO2 exhibited abnormally low height of the Ni-O peak. This phenomenon is explained by the Jahn—Teller distortion of the NiO6 octahedron due to the low spin Ni3+ (d7) ion. De-intercalation of the Li ion caused oxidation of Ni3+ (d7) to Ni4+ (d6) and reduced the distortion, hence the Ni-O peak increased with increasing x value. The crystal structures of LiNiO2 treated with D2O, and electrochemically de-intercalated Li0.34NiO2 were solved by Rietveld analysis of neutron diffraction data.

In situ measurements of the Ni and Co K-edge XAFS spectra of Li1-xNiO2 and Li1-xCoO2 as a function of x were successfully carried out for the first time using an electrochemical cell. It is observed that a local Jahn-Teller distortion of the NiO6 octahedron in LiNiO2 was reduced with deintercalation of Li which caused oxidation of the Jahn-Teller d7Ni3+ ion to d6Ni4+ ion. A substitution of Co for Ni in LiNiO2 also reduced the local distortion of the NiO6 octahedron. XANES spectra of LiNiO2 shifted to higher energy side with increasing x while an abrupt shape change was observed in the XANES spectra of Li1-xCoO2 corresponding to phase transition.

The variation of iron chemical forms during the teeth formation of chiton, a well-known iron accumulator, was clarified by utilizing the fluorescence XAFS technique. Fe K-XANES spectra of the teeth of chiton in various maturation stages show a complex oxidation/reduction process of iron during the teeth formation. In the earliest stage of the maturation, an amorphous ferritin-like ferric compound accumulates in the framework of the organic substances. Magnetite formation occurs abruptly in the next maturation stage, and the color of the teeth changes from reddish brown to gray. The spectra of the teeth in the latter maturation stages show that the edge-energy is higher than that of magnetite and their pre-edge peak height are lower than that These results suggest that the fully mineralized teeth are considered to be a mixture of magnetite and a ferric compound and the content of magnetite decreases with the maturation of teeth.

Recent developments of X-ray optics for fabrication of synchrotron X-ray microprobe in hard X-ray region were reviewed. Potentail ability of X-ray microprobe was demonstrated through the XRF analysis of biological samples and μ-XANES analysis of meteorite samples.

Metallothionein-II (MT-II) and Cu, Zn-superoxide dismutase (Cu, Zn-SOD) interacted with mercury were detected by a new method utilizing isoelectric focusing-agarose or -polyacrylamide gel electrophoresis (IEF-AGE or IEF-PAGE) and nondestructive one-dimensional synchrotron radiation X-ray fluorescence (SR-XRF) analysis. When MT-II reacted with mercuric chloride, an obvious change of isoelectric point (pI = 3.7 - 4.7) for the intact form to alkaline pI (9.4) was observed. This marked migration of MT-II by the metal was blocked by addition of glutathione, suggesting that sulfhydryl functions participate in the pI variation. In contrast, interaction of Cu, Zn-SOD with mercury did not cause any changes of its pI although the metal bound tightly to Cu, Zn-SOD after electrophoresis; however, the enzyme activity was drastically suppressed. These observations indicate that combination of electrophoresis with SR-XRF analysis is an useful technique for detecting structural or functional alteration of protei...

Gerstleyite [Na2Sb8S13·2H2O] was successfully synthesized by hydrothermal method for the first time. The syntheses condition was as follows: starting material Sb2S3 and Na2S·9H2O soln. with mixing ratio of [Sb/Na]=4.0 and 8.0 (mol/mol), heating temperature 210 and 220°C, and heating time of 80 hours. The products were identified to be gerstleyite by means of X-ray powder diffraction. Space group and lattice constants were examined by a Weissenberg camera. Crystal data: monoclinic, Cm, a=9.945(2), b=23.134(3), c=7.108(1) A, β=127.828(8)°. The lattice parameters of the synthetic gerstleyite are 0.2∼0.4% larger than those reported for natural gerstleyite [Na2(Sb, As)8S13·2H2O], in which about one tenth of the Sb atoms were substituted by smaller As atoms.

Distribution of trace elements such as Cu, Se, and Zn in human kidney was examined by use of nondestructive synchrotron radiation X-ray fluorescence (SR-XRF) imaging technique. All elements measured were more accumulated in the renal cortex than in the medulla. The renal Cu and Zn distributions obtained by SR-XRF imaging were consistent with those obtained by inductively coupled plasma atomic emission spectrometry (ICP-AES). Furthermore, correlation analysis based on the X-ray intensity data of each analytical point showed a positive correlation of the distribution of these elements.

ピザラガイは,鉄を高濃度に濃集した歯を形成し,この歯が磁性を持つことからユニークな存在として注目されている.鉄を濃集した歯は基底膜の上に約70対存在し,その成熟過程で形状が変化するが,本研究ではそれに伴う鉄の化学形の変化を調べるためにシンクロトロン放射光を利用するX線吸収微細構造(XAFS)法を適用した.X線回折の測定からは結晶成分としては磁鉄鉱のみが検出され,更にX線プローブマイクロアナリシス(EPMA)により鉄は歯の先端部から腹側にかけての摂餌面に局在していることが確認された.蛍光XAFS測定の結果,歯の形成初期の段階では鉄は三価の非晶質酸化水酸化物(FeOOH)として沈着され,その後部分的に還元を受け二価と三価の混合した磁鉄鉱(Fe3O4)を形成してゆくことが明らかとなった.又,ピザラガイの歯は成熟過程において,褐色,灰色,赤色,黒色と4段階の変色を示すが,歯に含まれる鉄の状態もこれに伴い変化しており,歯の外観と鉄の化学形に相関があることが分かった.

A monolayer film of unilamellar titania crystallites consisting of two planes of Ti/O atoms and two additional planes of O atoms underwent an interesting structural change by heat treatment at 800 °C and above to produce anatase nanocrystals oriented along the c-axis. This phenomenon is distinct from phase transformation of the bulk phase in terms of the significantly higher crystallization temperature of anatase and the preferential orientation of nanocrystals. This may be peculiar to two-dimensional nanosystems, providing a new route for the fabrication of oriented nanocrystals.

Layered NaNi(0.5)Mn(0.5)O(2) (space group: R ̅3m), having an O3-type (α-NaFeO(2) type) structure according to the Delmas' notation, is prepared by a solid-state method. The electrochemical reactivity of NaNi(0.5)Mn(0.5)O(2) is examined in an aprotic sodium cell at room temperature. The NaNi(0.5)Mn(0.5)O(2) electrodes can deliver ca. 105-125 mAh g(-1) at rates of 240-4.8 mA g(-1) in the voltage range of 2.2-3.8 V and show 75% of the initial reversible capacity after 50 charge/discharge cycling tests. In the voltage range of 2.2-4.5 V, a higher reversible capacity of 185 mAh g(-1) is achieved; however, its reversibility is insufficient because of the significant expansion of interslab space by charging to 4.5 V versus sodium. The reversbility is improved by adding fluoroethylene carbonate into the electrolyte solution. The structural transition mechanism of Na(1-x)Ni(0.5)Mn(0.5)O(2) is also examined by an ex situ X-ray diffraction method combined with X-ray absorption spectroscopy (XAS). The staking sequence of the [Ni(0.5)Mn(0.5)]O(2) slabs changes progressively as sodium ions are extracted from the crystal lattice. It is observed that the original O3 phase transforms into the O'3, P3, P'3, and P3" phases during sodium extraction. XAS measurement proves that NaNi(0.5)Mn(0.5)O(2) consists of divalent nickel and tetravalent manganese ions. As sodium ions are extracted from the oxide to form Na(1-x)Ni(0.5)Mn(0.5)O(2), nickel ions are oxidized to the trivalent state, while the manganese ions are electrochemically inactive as the tetravalent state.

We have started the construction of a nationwide forensic soil sediment database for Japan based on the heavy mineral and trace heavy element compositions of stream sediments collected at 3024 points all over Japan obtained by high-resolution synchrotron X-ray powder diffraction (SR-XRD) and high-energy synchrotron X-ray fluorescence analysis (HE-SR-XRF). In this study, the performance of both techniques was demonstrated by analyzing soil sediments from two different geological regions, the Kofu and Chiba regions in Kanto province, to construct database that can be applied in the future to provenance analysis of soil evidence from a crime scene. The sediments from the quaternary volcanic lithology of the Chiba region were found to be dominated by heavy minerals of volcanic origin - orthopyroxene, clinopyroxene, and amphibole, and the REEs (rare earth elements) within the region showed similar geochemical behavior. On the other hand, four distinct heavy mineral groups were identified in the sediments of the Kofu region, where there is a great variety of underlying bedrock, and the geochemical behavior of the REEs in the sediments also varied accordingly to their geological origins. As such, our study shows that high-resolution SR-XRD data can provide information on the spatial distribution patterns of heavy minerals in stream sediments, playing an important role in determining their likely geographical origin. Meanwhile, the highly sensitive HE-SR-XRF data allow us to study the geochemical behavior of trace heavy elements, especially the REEs in the sediments, providing additional support to further constrain the likely geographical origin of the sediments determined by heavy minerals.

Trace elemental analysis of soybeans was performed using X-ray fluorescence (XRF) analysis in order to characterise the geographical origins of the beans. By optimising the measurement conditions of an energy-dispersive XRF spectrometer equipped with three-dimensional polarisation optics, determination of trace elements at the sub-μg g−1 level in soybean samples was accomplished. Forty-six samples were analysed. Results showed that there were some differences between the trace element contents, reflecting a difference in their geographical origins. A statistical analysis showed that the concentrations of eight elements (Mg, P, Cl, K, Mn, Cu, Br, and Ba) are good parameters for constructing a discriminant function for geographical origin. In conclusion, we were able to accurately distinguish between domestic and imported soybeans. The present work demonstrates that XRF is useful as a rapid and simple tool for provenance analyses of agricultural products.

Lithium-excess manganese layered oxides, which are commonly described by the chemical formula zLi(2)MnO(3)-(1-z)LiMeO(2) (Me = Co, Ni, Mn, etc.), are of great importance as positive electrode materials for rechargeable lithium batteries. In this Article, Li(x)Co(0.13)Ni(0.13)Mn(0.54)O(2-δ) samples are prepared from Li(1.2)Ni(0.13)Co(0.13)Mn(0.54)O(2) (or 0.5Li(2)MnO(3)-0.5LiCo(1/3)Ni(1/3)Mn(1/3)O(2)) by an electrochemical oxidation/reduction process in an electrochemical cell to study a reaction mechanism in detail before and after charging across a voltage plateau at 4.5 V vs Li/Li(+). Changes of the bulk and surface structures are examined by synchrotron X-ray diffraction (SXRD), X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectroscopy (SIMS). SXRD data show that simultaneous oxygen and lithium removal at the voltage plateau upon initial charge causes the structural rearrangement, including a cation migration process from metal to lithium layers, which is also supported by XAS. This is consistent with the mechanism proposed in the literature related to the Li-excess manganese layered oxides. Oxygen removal associated with the initial charge on the high voltage plateau causes oxygen molecule generation in the electrochemical cells. The oxygen molecules in the cell are electrochemically reduced in the subsequent discharge below 3.0 V, leading to the extra capacity. Surface analysis confirms the formation of the oxygen containing species, such as lithium carbonate, which accumulates on the electrode surface. The oxygen containing species are electrochemically decomposed upon second charge above 4.0 V. The results suggest that, in addition to the conventional transition metal redox reactions, at least some of the reversible capacity for the Li-excess manganese layered oxides originates from the electrochemical redox reaction of the oxygen molecules at the electrode surface.

Hexagonal rare earth carbonate hydroxides, RE(CO 3 )OH, where RE = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, and Er, were hydrothermally synthesized from formic acid and hydroxide gels of rare earth elements. The crystals exhibited bicephalous hexagonal prisms with lengths of several tens of micrometers. The crystal structures of a series of hexagonal RE(CO 3 )OH were solved using the single crystal CCD-XRD intensity data sets. The space groups of the synthetic hexagonal RE(CO 3 )OH crystals are all P6. The present study has cast doubt upon the space group P62c previously reported for the natural Ce(CO 3 )OH, hydroxylbastnasite-(Ce). The cell parameters decreased linearly with decreases in the ionic radii of the rare earth elements. La(CO 3 )OH showed the largest unit cell (a = 12.6752(6), c = 10.0806(10) A), while Er(CO 3 )OH showed the smallest (a = 11.8977(4), c = 9.6978(8) A). The rare earth atoms are in ninefold coordination with oxygen atoms to form a tricapped trigonal prism. The structure consists of layers of 2 ∞ [(OH)RE 3/3 ] 2+ ions linked by carbonate ions. Raman spectra indicate the presence of carbonate and hydroxide groups. An evolutionary shift was observed from La to Er towards higher frequency, which was associated with a decreasing RE-O bond length.

The crystal structure of Na3Sb7O9Se3·Sb0.319(H2O,OH)3 has been determined using a single crystal prepared by hydrothermal synthesis to a conventional R = 0.043, Rw = 0.039 for 1556 reflections. It is hexagonal with a space group of P63; a = 14.422(4), c = 5.5448(8) A, Z = 2. The structure consists of infinite tunnels formed by the linkages of SbO3 pyramids. SbSe3 pyramids among the tunnels connect the tunnels to form a three-dimensional structure. Na atoms were on the inside wall of the tunnel. It was revealed that statistically occupied Sb(H2O,OH)6-octahedra are located at the center of the tunnel. Two statistical sites for the Sb atom of the SbSe3 pyramids are pointed out.

Chemical states and structural changes accompanying the electrochemical Li deintercalation of Li 1− x Mn 2− y Cr y O 4 ( y =1/9,1/6,1/3) were studied by the in situ X-ray absorption fine structure (XAFS) technique. The X-ray absorption near-edge structures (XANES) of Mn and Cr as a function of x showed that the 4 V plateau of the material can be ascribed to the oxidation of Mn 3+ to Mn 4+ , and Cr does not contribute to the charging, but to the stabilization of the spinel structure against the delithiation. The extended EXAFS analysis of Li 1− x (Mn, Cr) 2 O 4 revealed that the Jahn–Teller distorted Mn 3+ –O octahedra become uniform when the cell is fully charged.

The dissolution process of Mn from LiMn2O4 cathode into an electrolyte solution accompanied on electrochemical cycling at various temperature was studied for the first time by in situ methods using a combination of total reflection X-ray fluorescence (TXRF) analysis and a capillary technique. When the in situ cell was cycled at 50°C, the Mn concentrations measured on the 5th, 10th and 15th cycles were determined to be 11, 56 and 393 ppm, respectively. The concentration of Mn in the cell was shown to be the highest at the center of both electrodes. It was also found that dissolution of Mn from the cathode material takes place during the charge rather than the discharge process. Mn K-XANES (X-ray absorption near-edge structure) spectra of the electrolyte solution revealed that Mn exists as Mn2+.

A new laboratory spectrometer for X-ray Induced Electron Emission Spectroscopy (XIEES) has been developed. This spectrometer is suitable for measurements of X-ray Absorption Fine Structure (XAFS) spectrum in surface sensitive fluorescence and electron emission detection modes as well as in standard transmission mode. It is the advantage of this spectrometer that a wide range of X-ray energy scanning between 0.48 and 41 keV is available. At the Cu K-edge, an energy resolution of about 2 eV has been achieved. The spectrometer has been used to analyze the Al2O3 (40 Å and 500 Å)/Si(100) with total electron yield measurement.

The crystal structure of Na3Sb7O9Se3·Sb0.319(H2O,OH)3 has been determined using a single crystal prepared by hydrothermal synthesis to a conventional R = 0.043, Rw = 0.039 for 1556 reflections. It is hexagonal with a space group of P63; a = 14.422(4), c = 5.5448(8) A, Z = 2. The structure consists of infinite tunnels formed by the linkages of SbO3 pyramids. SbSe3 pyramids among the tunnels connect the tunnels to form a three-dimensional structure. Na atoms were on the inside wall of the tunnel. It was revealed that statistically occupied Sb(H2O,OH)6-octahedra are located at the center of the tunnel. Two statistical sites for the Sb atom of the SbSe3 pyramids are pointed out.

On the occation of the 10th anniversary of the Photon Factory, National Laboratory for High Energy Physics, Tsukuba, Japan, a review of work done in the field of mineralogy has been made. This paper includes a complete list of the publications in the field of the mineralogical applications of synchrotron radiation in Japan, covering the development of instrumentations and mineralogical applications of X-ray diffraction, XAFS, X-ray fluorescence analysis, X-ray topography and computerized tomography.

Forms of iron in leaves of wild-type tomato (Lycopersicon esculentum Mill. cv. Bonner Beste) and of the nicotianamine-free mutant, chloronerva, were analysed by X-ray absorption near-edge structure (XANES). The XANES spectra of the wild-type leaf veins and of the interveinal areas of leaves of both wild-type and chloronerva had a lower edge energy than the spectrum of the chloronerva leaf veins. This decrease may be caused by the presence of ferrous iron. Thus nicotianamine may play an important role in maintaining iron in the ferrous form in the veins of tomato leaves. Copyright © 2000 John Wiley & Sons, Ltd.

High-energy synchrotron radiation x-ray fluorescence spectrometry (SR-XRF) utilizing 116 keV x-rays was used to characterize titanium dioxide pigments (rutile) and automotive white paint fragments for forensic examination. The technique allowed analysis of K lines of 9 trace elements in 18 titanium dioxide pigments (rutile), and 10 trace elements in finish coat layers of seven automotive white paint fragments. High-field strength elements (HFSE) were found to strongly reflect the origin of the titanium dioxide (TiO(2)) pigments, and could be used as effective parameters for discrimination and classification of the pigments and paint fragments. A pairwise comparison of the finish coat layers of seven automotive white paint fragments was performed. The trace elements in the finish coat layers detected by the high-energy SR-XRF were especially effective for identification. By introducing the trace element information of primer and electrocoat layers, all the automotive white paint fragments could be discriminated by this technique.