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Probe Microanalysis (probe + microanalysi)
Kinds of Probe Microanalysis Selected AbstractsHigh-Pressure Torsion for Giant Magnetoresistance and Better Magnetic Properties,ADVANCED ENGINEERING MATERIALS, Issue 8 2010Shingo Nishihata High-pressure torsion (HPT) was conducted on Cu alloys containing ferromagnetic Co and Fe particles. Electron probe microanalysis, X-ray diffraction analysis, and transmission electron microscopy confirmed that the particles were significantly refined through fragmentation and some fractions were dissolved into the Cu matrix with straining by HPT. Saturation magnetization decreases with straining and coercive force increases with straining but they level off after intense straining. Magnetoresistance with an isotropic feature corresponding to giant magnetoresistance (GMR) appears at room temperature by processing with HPT. It is demonstrated that HPT is a potential process for controlling magnetic properties such as saturation magnetization and coercive force and also for creating GMR in the alloys prepared by conventional ingot metallurgy. [source] WDX Studies on Ceramic Diffusion Barrier Layers of Metal Supported SOECsFUEL CELLS, Issue 6 2009D. Wiedenmann Abstract Solid oxide electrolyser cells (SOECs) have great potential for efficient and economical production of hydrogen fuel. Element diffusion between the Ni-cermet electrode and the metal substrate of metal supported cells (MSC) is a known problem in fuel cell and electrolysis technology. In order to hinder this unintentional mass transport, different ceramic diffusion barrier layers (DBLs) are included in recent cell design concepts. This paper is based on wavelength dispersive X-ray fluorescence investigations of different SOEC and focuses on Fe, Cr and Ni diffusion between the metal grains of the cathode and the metal substrate. Due to the low detection limits and therefore high analytical sensitivity, wavelength dispersive electron probe microanalysis (EPMA) provides a precise method to determine element distribution, absolute element concentration and changes between the reference material and aged cells on a microstructural level by element mappings and concentration profiles. The results of this work show considerable concentration gradients in the metal grains caused by mass exchange during cell operation. Diffusion can be inhibited significantly by integrating different ceramic DBLs of doped LaCrO3 -type or doped LaMnO3 -type perovskite, either by vacuum plasma spraying (VPS) or physical vapour deposition technique (PVD). [source] Monte Carlo Study of Quantitative Electron Probe Microanalysis of Monazite with a Coating Film: Comparison of 25 nm Carbon and 10 nm Gold at E0= 15 and 25 keVGEOSTANDARDS & GEOANALYTICAL RESEARCH, Issue 2 2007Takenori Kato simulation par la méthode de Monte Carlo; microanalyse par sonde électronique (EPMA); analyse quantitative; film de revêtement; monazite Carbon (25,30 nm in thickness) is the most common coating material used in the electron probe microanalysis (EPMA) of geological samples. A gold coating is also used in special cases to reduce the surface damage by electron bombardment. Monte Carlo simulations have been performed for monazite with a 25 nm carbon and a 10 nm gold coating to understand the effect of a coating film in quantitative EPMA at E0= 15 keV and 25 keV. Simulations showed that carbon-coated monazite gave the same depth distribution of the generated X-rays in the monazite as uncoated monazite, whilst gold-coated monazite gave a distorted depth distribution. A 10 nm gold coating was 1.06 (15 keV) and 1.05 (25 keV) times higher in k -ratio between monazite and pure thorium than a 25 nm carbon coating at an X-ray take-off angle of 40 degrees. Thus, a 10 nm gold coating is a possible factor contributing to inaccuracy in quantitative EPMA of monazite, while a 25 nm carbon coating does not have a significant effect. Le carbone, avec des épaisseurs de 25 à 30 nm, est le matériel de dépôt le plus fréquemment utilisé en microanalyse par sonde électronique (EPMA) d'échantillons géologiques. Un dépôt d'or est aussi utilisé dans des cas spécifiques, pour réduire les dommages causés à la surface par le bombardement d'électrons. Des simulations par la méthode de Monte Carlo ont été effectuées pour une monazite recouverte d'une couche de carbone de 25 nm et d'une couche d'or de 10 nm, dans le but de comprendre l'effet du dépôt dans les mesures quantitatives à l'EPMA, à E0= 15 keV et 25 keV. Les simulations ont montré que la monazite recouverte de carbone avait la même distribution en profondeur de rayons X générés qu'une monazite non recouverte, tandis que la monazite recouverte d'or avait une distribution en profondeur déformée. Le dépôt de 10 nm d'or avait un k -ratio qui était 1.06 (pour 15 keV) et 1.05 (pour 25 keV) fois plus important pour la monazite et du thorium pur que le dépôt de 25 nm de carbone dans le cas d'un angle de sortie des rayons X de 40 degrés. En conséquence un dépôt d'or de 10 nm est un facteur possible d'inexactitude lors de mesures quantitatives de monazites par EPMA, alors qu'un dépôt de carbone de 25 nm n'a pas d'effet significatif sur la mesure. [source] Application of High Spatial Resolution Laser Ablation ICP-MS to Crystal-Melt Trace Element Partition Coefficient DeterminationGEOSTANDARDS & GEOANALYTICAL RESEARCH, Issue 1 2007Maurizio Petrelli ICP-MS; ablation laser; éléments en trace; figure de mérite; coefficients de partage entre cristal et liquide In this contribution we evaluate the capabilities of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) using a 12 ,m spot size. Precision, accuracy and detection limits were assessed on the USGS BCR-2G reference material. We demonstrate that the 12 ,m LA-ICP-MS analyses of experimentally-grown amphibole and garnet are in excellent agreement with secondary ion mass spectrometry (SIMS) trace element determinations on the same crystals. The 12 ,m spot size configuration was subsequently used to determine trace element crystal-melt partition coefficients (Dc/m) for a wide range of trace elements in amphibole in equilibrium with a basanitic melt. The following strategy to determine accurately and evaluate Dc/m is proposed. One or more major elements determined previously by electron probe microanalysis (EPMA) was used to ensure consistency between EPMA and the composition of the aerosol produced by the laser ablation. Measured Dc/m values were successively evaluated using the lattice strain model. The use of this strategy significantly improved the precision and accuracy of Dc/m determination when a LA-ICP-MS configuration with a high spatial resolution was employed. Dans cet article nous évaluons les potentialités de l'ablation laser couplée à un spectromètre de masse à plasma induit (LA-ICP-MS) en travaillant avec un diamètre d'impact de 12 ,m. Précision, justesse et limites de détections sont évaluées sur le matériau de référence BCR-2G de l'USGS. Nous démontrons que les analyses LA-ICP-MS faites avec un diamètre de 12 ,m sur les amphiboles et des grenats synthétiques sont en excellent accord avec les déterminations d'éléments en trace effectuées sur les mêmes cristaux par sonde ionique (SIMS). Ce diamètre d'impact de 12 ,m a donc été sélectionné pour déterminer les coefficients de partage cristal/liquide (Dc/m) pour un grand nombre d'éléments en trace dans une amphibole en équilibre avec un liquide basanitique. Nous proposons la stratégie d'analyse suivante, qui assure une détermination exacte des coefficients de partage Dc/m. Un ou plusieurs des éléments majeurs déterminés auparavant par microsonde électronique (EMPA) est utilisé pour garantir la consistance des données entre EMPA et la composition de l'aérosol produit par l'ablation laser. Les Dc/m mesurés sont ensuite évalués en utilisant le modèle de contrainte de réseau. L'utilisation de cette stratégie améliore de manière significative la précision et la justesse des déterminations de Dc/m quand elle est couplée à l'utilisation d'un système LA-ICP-MS de grande résolution spatiale. [source] Further Characterisation of the 91500 Zircon CrystalGEOSTANDARDS & GEOANALYTICAL RESEARCH, Issue 1 2004Michael Wiedenbeck zircon 91500; matériau de référence; intercomparaison entre techniques; valeurs de travail This paper reports the results from a second characterisation of the 91500 zircon, including data from electron probe microanalysis, laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS), secondary ion mass spectrometry (SIMS) and laser fluorination analyses. The focus of this initiative was to establish the suitability of this large single zircon crystal for calibrating in situ analyses of the rare earth elements and oxygen isotopes, as well as to provide working values for key geochemical systems. In addition to extensive testing of the chemical and structural homogeneity of this sample, the occurrence of banding in 91500 in both backscattered electron and cathodoluminescence images is described in detail. Blind intercomparison data reported by both LA-ICP-MS and SIMS laboratories indicate that only small systematic differences exist between the data sets provided by these two techniques. Furthermore, the use of NIST SRM 610 glass as the calibrant for SIMS analyses was found to introduce little or no systematic error into the results for zircon. Based on both laser fluorination and SIMS data, zircon 91500 seems to be very well suited for calibrating in situ oxygen isotopic analyses. Cet article présente les résultats d'une nouvelle caractérisation du zircon 91500, dont des données de microanalyse par sonde électronique, d'analyse par ablation laser en couplage à un ICP-MS, d'analyse par sonde ionique (SIMS) et d'analyse par fluorination laser. Le but de cette étude etait de démontrer que ce large monocristal de zircon pouvait être utilisé pour la calibration d'analyses in situ de Terres Rares et des isotopes de I'Oxygène, et en même temps de fournir des valeurs "de travail" pour un certain nombre de systémes géochimiques cruciaux. En complément des tests systématiques d'homogénéité de I'échantillon, tant chimiquement que structurellement, /'ex/sfence, dans le zircon 91500, de zonages visibles en électrons retro diffusés et en cathodoluminescence, est décrite en détail, line comparaison en aveugle des résultats obtenus par LA-ICP-MS et par SIMS, dans des laboratoires différents, montre que les différences systématiques entre les ensembles de données obtenues par ces deux techniques sont très faibles. De plus, I'utilisation du verre NIST SRM 610 comme calibrant lors de I'analyse par SIMS n'introduit qu'une erreur systématique très faible si ce n'est inexistante sur les résultats du zircon. Sur la base des analyses par fluorination laser et par SIMS, le zircon 91500 semble être parfaitement adapte a son utilisation pour la calibration d'analyses isotopiques in situ d'oxygène. [source] SHRIMP zircon and EPMA monazite dating of granitic rocks from the Maizuru terrane, southwest Japan: Correlation with East Asian Paleozoic terranes and geological implicationsISLAND ARC, Issue 3 2008Masahiro Fujii Abstract The Maizuru terrane, distributed in the Inner Zone of southwest Japan, is divided into three subzones (Northern, Central and Southern), each with distinct lithological associations. In clear contrast with the Southern zone consisting of the Yakuno ophiolite, the Northern zone is subdivided into the western and eastern bodies by a high-angle fault, recognized mainly by the presence of deformed granitic rocks and pelitic gneiss. This association suggests an affinity with a mature continental block; this is supported by the mode of occurrence, and petrological and isotopic data. Newly obtained sensitive high mass-resolution ion microprobe (SHRIMP) zircon U,Pb ages reveal the intrusion ages of 424 ± 16 and 405 ± 18 Ma (Siluro,Devonian) for the granites from the western body, and 249 ± 10 and 243 ± 19 Ma (Permo,Triassic) for the granodiorites from the eastern body. The granites in the western body also show inherited zircon ages of around 580 and 765 Ma. In addition, electron probe microanalysis (EPMA) monazite U,Th,total Pb dating gives around 475,460 Ma. The age of intrusion, inherited ages, mode of occurrence, and geological setting of the Siluro,Devonian granites of the Northern zone all show similarities with those of the Khanka Massif, southern Primoye, Russia, and the Hikami granitic rocks of the South Kitakami terrane, Northeast Japan. We propose that both the Siluro,Devonian and Permo,Triassic granitic rocks of the Northern zone are likely to have been juxtaposed through the Triassic,Late Jurassic dextral strike-slip movement, and to have originated from the Khanka Massif and the Hida terrane, respectively. This study strongly supports the importance of the strike-slip movement as a mechanism causing the structural rearrangement of the Paleozoic,Mesozoic terranes in the Japanese Islands, as well as in East Asia. [source] Environmental signature in the otolith elemental fingerprint of the tapertail anchovy, Coilia mystus, from the Changjiang estuary, ChinaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2006J. Yang Summary The ontogenetic patterns of habitat use and the migratory history of the tapertail anchovy, Coilia mystus, collected in the Changjiang estuary around Chongming Island, China, were studied by examining the environmental signature in the otolith strontium (Sr) and calcium (Ca) fingerprints using electron probe microanalysis (EPMA). Our results suggest that the migration strategy of C. mystus is much more flexible than supposed in the literature to date. The spring spawning population of C. mystus from the studied area was found to consist of individuals with different migration histories. Although the tapertail anchovy seems to be an anadromous fish that spawns and hatches in a freshwater habitat, it can also use a freshwater environment in non-spawning seasons. The otolith EPMA of the elemental fingerprint (Sr x-ray maps and Sr : Ca ratios) is an environmental indicator that can be applied to the migratory ecology of other important diadromous species in China. [source] Calcium phosphate formation on the phosphorylated dental bonding agent in electrolyte solutionJOURNAL OF ORAL REHABILITATION, Issue 1 2004T. Hayakawa summary, The aim of the present study was to study the mineral formation on a phosphorylated dental bonding agent using a mineralization inductive solution. Clearfil Photobond, which contained phosphate monomer, was cured by photo-irradiation and heat treated, and was then immersed in Hanks' balanced salt solution (HBSS) with pH = 7·4 for 1, 3, 5, 7, 14, and 28 days at 37 °C. The white substances were deposited on the phosphorylated polymer, i.e. cured Photobond disk, after the immersion in HBSS. The white substances become visible after 3 days immersion. After 7 days immersion, surface of the phosphorylated polymer disk was almost covered with white substance layers. The measurement of white substances by means of X-ray diffraction, Fourier-transform infrared and electron probe microanalysis revealed that their main component was carbonate-containing hydroxyapatite. Scanning electron microscopy pictures showed that a large number of globules of hydroxyapatite were fused together, and that each globule was composed of a group of numerous thin-film form flakes uniting and/or clustering together. The results obtained in this study concluded that the presence of phosphonic acid and phosphate group of phosphorylated dental bonding agent enhanced the nucleation and growth of hydroxyapatite crystals on its surface. [source] Metal-Ceramic Interface Evaluation of a Gold-Infiltrated AlloyJOURNAL OF PROSTHODONTICS, Issue 7 2009Rupal Vasani BDS Abstract Purpose: The success of metal-ceramic systems partially depends on the formation of a stable bond between metal and porcelain. The purpose of this study was to investigate the porcelain/metal interface and the mechanism of interfacial bonding in a gold-infiltrated alloy (Captek). Materials and Methods: Captek specimens with feldspathic porcelain were evaluated by optical microscopy, scanning electron microscopy (SEM), electron probe microanalysis (EPMA), X-ray diffraction (XRD), and the Schwickerath crack initiation test for metal-ceramic bond compatibility. Specimens were processed with or without Capbond, a bonding agent. A traditional metal-ceramic alloy was also analyzed with microscopy for comparative purposes. Results: Optical and scanning electron micrographs of Captek specimens processed with Capbond revealed close adaptation of porcelain to the surface of the metal with sporadic nodules extending from the Captek surface. In contrast, the specimens of Captek without Capbond showed a much flatter porcelain/metal interface. Comparatively, the porcelain/metal interface of the traditional metal-ceramic crown showed greater surface roughness than the Captek specimens. No metal oxides were observed at the porcelain/metal interface of the Captek specimens with XRD. During the Schwickerath test, the Captek specimens permanently deformed, not allowing for crack initiation at the porcelain/metal interface. Conclusions: Microscopy and XRD analysis showed that micromechanical interlocking is the primary mechanism of porcelain adherence to Captek metal. The use of Capbond prior to porcelain application to Captek results in gold nodules on the surface to aid retention. Existing metal-ceramic bond compatibility standardized tests are not sufficient for evaluating Captek, primarily due to the flexibility of the material. [source] Towards a Holocene tephrochronology for Sweden: geochemistry and correlation with the North Atlantic tephra stratigraphyJOURNAL OF QUATERNARY SCIENCE, Issue 2 2004Jane Boygle Abstract Northern Europe has been affected by fallout of tephra from volcanic eruptions in Iceland throughout at least the Late-glacial and Holocene. Microscopic volcanic ash horizons found in the British Isles, northern Germany and Scandinavia (e.g. Hekla 4) now provide important regional isochrons. Over recent years analytical techniques such as electron probe microanalysis (EPMA) have helped identify these distal tephra layers by glass geochemistry. Early tephra work in Sweden used refractive indices and bracketing radiocarbon dates for identification, resulting in tentative correlation. This paper presents geochemical data for Icelandic Holocene tephra in Sweden. Several sites in central Sweden have four distinct mid-Holocene tephra layers. Correlation with the Icelandic record indicates that the following tephra layers are present: Hekla 4 (ca. 3830,yr,BP), Kebister tephra (ca. 3600,yr,BP), Hekla 3 (ca. 2880,yr,BP) and Askja ad 1875. Preliminary analyses suggest that more, previously unidentified, tephra layers are present in low concentrations in the region, indicating potential for expanding the Swedish tephrochronology for palaeoecological and palaeoenvironmental work in northern Europe. Copyright © 2004 John Wiley & Sons, Ltd. [source] Tephrological implications of beam size,sample-size effects in electron microprobe analysis of glass shardsJOURNAL OF QUATERNARY SCIENCE, Issue 2 2001John B. Hunt Abstract This paper concerns the potential consequences of varying procedures for the determination of tephra geochemistry by electron microprobe. Application of electron probe microanalysis to tephrostratigraphical methods has increasingly facilitated the resolution and refinement of Quaternary chronology associated with records of proxy-environmental or proxy-climatic change. The geographical range over which tephras are recovered has expanded significantly with the identification and analysis of crypto (or hidden) tephras in areas far removed from tephra sources. These tephras are dominated by glass shards, which, in many distal environments, may be either small in size (,m) or may be highly pumiceous with low glass:void ratios and thin (<10 ,m) shard walls. We demonstrate that reducing the size of the electron beam used to analyse shard geochemistry cannot be used reliably to permit analysis of thin glass walls. This approach distorts the geochemical data, creating analytical differences that may generate inappropriate tephrogeochemical fingerprints. Additional distortion of the geochemical fingerprint in the form of hybrid analyses may be encountered in glass fragments containing micron-sized crystalline phases such as feldspar. Copyright © 2001 John Wiley & Sons, Ltd. [source] Chemistry and Morphology of Hydrogarnets Formed in Cement-Based CASH Hydroceramics Cured at 200° to 350°CJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2009Konstantinos Kyritsis We have studied the chemistry and the morphology of hydrogarnet crystals produced in cement-based hydroceramic materials at elevated temperatures (200°,350°C) with silica and alumina additions. Such materials lie within the hydrothermal CaO,Al2O3,SiO2,H2O (CASH) system. Hydrogarnet Ca3Al2(SiO4)3,y(OH)4y is the dominant aluminum bearing phase formed and its composition is influenced mainly by the curing temperature and to a lesser degree by the addition of silica. The composition parameter y was estimated by Rietveld refinement of X-ray diffraction (XRD) data. Electron probe microanalysis (EPMA) shows that the hydrogarnets incorporate minor elements such as Fe, Mg, and S. EPMA data confirmed the hydrogarnet composition estimated from XRD. Both octahedral and icositetrahedral forms are observed. The icositetrahedral form is associated with higher minor element content. [source] Glass-to-Metal Seal Interfacial Analysis using Electron Probe Microscopy for Reliable Solid Oxide Fuel CellsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2009Scarlett J. Widgeon The chemical compatibility between sealing glasses and interconnect materials for solid oxide fuel cells (SOFCs) has been studied in SOFC environments. Two borate-based glass compositions were sealed to interconnect materials, 441 stainless-steel (441SS) and Mn1.5Co1.5O4 -coated 441SS. The Mn1.5Co1.5O4 -coated 441SS coupons were analyzed as-received using X-ray diffraction (XRD) and electron probe microanalysis (EPMA) to obtain structural information and concentration profiles, respectively. The concentration profiles and the lack of Fe-containing phases present in the XRD spectrum show Fe is present throughout the coating, suggesting that Fe is partially substituted in the Mn1.5Co1.5O4 spinel. The glass,metal coupons were heat treated in air at 750°C for 500 h. The specimens were analyzed by EPMA and scanning electron microscope (SEM) to obtain images of the glass microstructure at the interface, to verify seal adherence, and to record concentration profiles across the glass,metal interface, with an emphasis on Cr. In total, four seal configurations were tested and analyzed, and in all cases the glasses remained well adhered to the metal and coating, and there was no microstructural evidence of new reaction phases present at the interface. There was slight diffusion of Cr from the 441SS into the sealing glasses, and Cr diffusion was hindered by the coating on the coated 441SS samples. [source] In-Flight-Melted Soda-Lime-Silica Glass by RF Induction Thermal PlasmaJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2008Fuji Funabiki Granulated raw materials with a particle size of 20,80 ,m were prepared from a slurry of Na2CO3, CaCO3, and SiO2 (quartz) by the spray-dry method, and injected with carrier gas into a radio-frequency induction thermal plasma. Spherical particles 5,60 ,m in size were obtained and analyzed. Thermo-gravimetric analysis and X-ray diffraction analysis showed that during the short flight of the order of milliseconds, all carbonates were decomposed and >95% quartz was reacted into a noncrystalline state. Glass transition was clearly observed by differential thermal analysis. Increase of the carrier gas from 3 to 6 L/min led to a decrease in the volatilization ratio of Na2O from 46% to 18% with a slight decrease of the reaction ratio of quartz in trade balance. Electron probe microanalysis showed that the volatilization could be attributed to an excess heating of small particles <30 ,m, and suppression by the increase of carrier gas. [source] Preliminary Observations on Phase Relations in the "V2O3,FeO" and V2O3,TiO2 Systems from 1400°C to 1600°C in Reducing AtmospheresJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2000Theresa Coetsee Phase relations within the "V2O3,FeO" and V2O3,TiO2 oxide systems were determined using the quench technique. Experimental conditions were as follows: partial oxygen pressures of 3.02 × 10,10, 2.99 × 10,9, and 2.31 × 10,8 atm at 1400°, 1500°, and 1600°C, respectively. Analysis techniques that were used to determine the phase relations within the reacted samples included X-ray diffractometry, electron probe microanalysis (energy-dispersive spectroscopy and wavelength-dispersive spectroscopy), and optical microscopy. The solid-solution phases M2O3, M3O5, and higher Magneli phases (MnO2n,1, where M = V, Ti) were identified in the V2O3,TiO2 system. In the "V2O3,FeO" system, the solid-solution phases M2O3 and M3O4 (where M = V, Ti), as well as liquid, were identified. [source] Characterization of Sb-doped CuInS2 crystalsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2003H. Komaki Abstract CuInS2 semiconductor crystals were successfully grown by a hot-press (HP) method at 400,700,°C for 1,h at growth pressures from 10 to 100 MPa. The samples were 20 mm in diameter. The samples grown at 700,°C were found to be of chalcopyrite structure, nearly stoichiometric and n-type by means of X-ray diffraction, electron probe microanalysis and thermoprobe analysis, respectively. A donor,acceptor pair emission band was observed in the photoluminescence spectra at 10 K, indicating that the samples had both donor and acceptor impurity types. It was also found that p-type CuInS2 crystals could be obtained by Sb doping. It was suggested that the Sb atoms in the S site might enhance p-type conductivity. [source] Properties and interfacial bonding for regenerated cellulose,polyurethane/amylose acetate sipn composite filmsPOLYMER COMPOSITES, Issue 6 2000Jiahui Yu Composite films were obtained by placing a polyurethane/amylose acetate semi-interpenetrating polymer network (SIPN) coating onto the surfaces of regenerated cellulose (RC) film. The properties of the composite film, such as tensile strength, 79.9 MPa (in dry state), 49.5 MPa (in wet state), water resistance (R), 0.62, dimensional stability (Sc), 3.0%, and water vapor permeability (P), 5.96 × 10,5 Kgm,2h,1, are better than those of the uncoated RC film or RC film with PU coating. The interfacial strength was characterized with infrared spectroscopy (IR), ultraviolet spectroscopy (UV), transmission electron microscopy (TEM), and electron probe microanalysis (EPMA). The results showed the existence of covalent and hydrogen bonds between the SIPN coat layer and the RC layer. It was also found that the PU prepolymer in the coating layer penetrated into the cellulose bulk, and reacted with the cellulose molecules, which formed another SIPN. [source] Synthesis of phase-pure SnS particles employing dithiocarbamate organotin(IV) complexes as single source precursors in thermal decomposition experimentsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2010D. C. Menezes Abstract Preparation of tin(II) sulfide, semiconductor material, has been accomplished by thermal decomposition of easily prepared organotin dithiocarbamate complexes: [Sn{S2CNEt2}2Ph2] (1), [Sn{S2CNEt2}Ph3] (2), [Sn{S2CNEt2}3Ph] (3) and [Sn{S2CN(C4H8)}2Bu2] (4). Phase-pure tin(II) sulfide has been obtained by pyrolysis of these precursors at 350 °C in N2. Thermogravimetric analysis, X-ray powder diffraction, scanning electron microscopy, X-ray electron probe microanalysis and 119Sn Mössbauer spectroscopy revealed that the complexes decompose in a single and sharp step (1 and 2), or in pseudo-single stage (3 and 4), to produce SnS. We have also measured the bandgap energies of the residues using electronic spectroscopy in the solid state and the result relates well to that in the literature for SnS, 1.3 eV. A decomposition mechanism was also proposed for each complex based on electrospray ionization tandem mass spectrometric results. The synthetic method used in this work might be useful for the preparation of pure SnS on a large scale. Copyright © 2010 John Wiley & Sons, Ltd. [source] PRODUCTION TECHNOLOGY OF ROMAN LEAD-GLAZED POTTERY AND ITS CONTINUANCE INTO LATE ANTIQUITYARCHAEOMETRY, Issue 5 2010M. S. WALTON A broad selection of Roman lead-glazed pottery dating from the first century ad through the fifth century ad was studied to establish locations of workshops and to address their technology of production. The ceramic bodies were analysed by ICP,AES. In addition, lead isotope analysis was undertaken on a selection of glazes. These findings suggested that there were several regions responsible for the production of lead-glazed ceramics in the western Roman world, including central Gaul, Italy and, probably, Serbia and Romania. Using the body compositions as a starting point, the glazing techniques employed by each of the potential workshops were examined using electron probe microanalysis. It was determined that there were two primary methods of glazing. The first method used lead oxide by itself applied to non-calcareous clay bodies, and the second method used a lead oxide-plus-quartz mixture applied to calcareous clay bodies. Based on these data for clay composition and glazing method, transfer of technology from the Hellenistic east to the western Roman world was proposed. Likewise, the inheritance of lead-glazing technology into late antiquity was established by making comparisons to lead-glazed ceramics dating to the seventh to ninth centuries from Italy, the Byzantine world and Tang Dynasty China. [source] | ||||||||||||||||||||||