bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of silanes on the interfacial compositions of epoxy/metal adhesive bonds: XPS and RAIR analyses
Authors: Hong S. G. , Boerio F. J. 
Published: May 2005

AbstractThe effects of silanes on the interfacial compositions of adhesive bonds formed by curing silanes with the epoxy/amidoamine adhesive against clean and oiled cold‐rolled steel (CRS) and electrogalvanized steel (EGS) substrates are studied using x‐ray photoelectron spectroscopy (XPS) and reflection absorption infrared spectroscopy (RAIR). Silanes used are N‐(2‐aminoethyl)‐γ‐aminopropyltrimethoxy silane (γ‐AEAPS), γ‐glycidoxypropyltrimethoxysilane (γ‐GPS) and γ‐mercaptopropyltrimethoxysilane (γ‐MPMS). The XPS results show that the addition of silanes to the adhesive increases the number of C—O bonds and decreases the N/C ratios in the resins of the interfacial regions. The addition of silane could help the adhesive bond with the oiled substrates. The RAIR results confirm that adding various silanes to the adhesive can change the compositions in EGS/adhesive interfaces differently and affect the preferential adsorption of amino groups from the adhesive on the EGS surface. Silanes can also increase the protonation of amino groups in the adhesive on the clean and the oiled CRS surfaces. However, the absence of protonated amino groups in the adhesive/EGS interfaces indicates that the protonation is metal dependent. X‐ray photoelectron spectroscopy detects two S 2p species in the bonding interface of the specimen prepared using γ‐MPMS‐added adhesive cured against EGS substrate. The higher binding energy S 2p is attributed to the chemical reaction of mercapto groups in the γ‐MPMS with the zinc surfaces.
XPS of oxidized wool fibre surfaces
Authors: Bradley R. H. , Clackson I. L. , Sykes D. E. 
Published: May 2005

AbstractOxygen plasma and ultra violet (UV) ozone treatments have been used to oxidize the surfaces of batches of natural wool fibres and woven cloths. The changes in surface composition and chemistry induced by these treatments have been followed using X‐ray photoelectron spectroscopy (XPS).Oxidation of surface proteinaceous di‐sulphide sulphur to sulphonic acid groups (SO3H) containing S(6+) is shown to occur for both treatments. However, oxidation at levels of approximately 90% is apparent for the UV ozone treatment which is significantly higher than levels achieved using oxygen plasmas (30%). Both treatments also lead to oxidation of surface carbon species. The data presented indicate that the UV ozone treatment used is capable of producing surface sulphur and carbon chemistry of the type usually obtained industrially by wet chemical methods which have the disadvantage of producing chlorinated effluent.
Radiation effects in static SIMS of polymers
Authors: Licciardello A. , Wenclawiak B. , Boes C. , Benninghoven A. 
Published: May 2005

AbstractThe formation of dimerized polystyrene molecules during static SIMS measurements, already reported in a previous paper [Surf. Interface Anal. 20, 549 (1993)] has been further investigated. Samples of styrene oligomers with very narrow molecular weight distribution were prepared by fractionating polystyrene standards by means of supercritical fluid chromatography and then irradiated in situ in a time‐of‐flight SIMS spectrometer. Pre‐irradiated samples have also been studied for comparison purposes. The results obtained confirm that crosslinked (dimerized) species are formed and detected in the very low fluence range, and strongly support the hypothesis that, at least partly, the observation of this kind of Ion beam modification is not due to ion impact overlaps during the measurement, but to primary modification/desorption events.
Mössbauer and Auger spectroscopic investigations of FeSi alloys produced by ion implanatation
Authors: Reuther H. 
Published: May 2005

AbstractFeSi alloys and compounds are of strong interest because of their electrical and magnetic properties. In thin layers they can be produced by ion implantation. To form iron‐rich alloys Si was implanted at room temperature into iron. Different energies (100, 200, and 300 keV) and ion doses (2 × 1017 to 1 × 1018 cm−2) were applied. The produced layers were investigated by Fe57 conversion electron Mössbauer spectroscopy (CEMS) and Auger electron spectroscopy (AES). CEMS was used to study the phases formed due to the ion implantation. Depending on the implantation parameters different disordered (probably amorphous) FeSi compounds were detected. Annealing of the samples resulted first in the precipitation of crystalline compounds and then in the beginning of the migration of Si out of the investigated range. The concentration profiles were determined with AES. Gaussian shaped Si profiles were found. Depending on the implantation parameters the maximum Si concentration detected was about 50 at.%.
Surface stoichiometry determination of SiOxNy thin films by means of XPS
Authors: Lozzi L. , Passacantando M. , Picozzi P. , Santucci S. , Tomassi G. , Alfonsetti R. , Borghesi A. 
Published: May 2005

AbstractThe surface stoichiometry of SiOxNy thin films has been studied by means of x‐ray photoelectron spectroscopy (XPS). The modified Auger parameter, applied on the Si 2p core level and Si KL2,3L2,3 Auger signal, has been used to calculate the surface composition of SiOxNy thin films prepared using different methods. The results have been compared with those obtained calculating the area under the XPS peaks and the Rutherford backscattering spectroscopy. The good agreement between these data indicates the validity of the modified Auger parameter as an easy and fast method, available in all electron spectroscopy laboratory, to study the surface stoichiometry of Si‐based compounds.
XPS study of amorphous As2S3 films deposited onto chromium layers
Authors: Petkov K. , Krastev V. , Marinova Ts. 
Published: May 2005

AbstractThis paper reports some XPS data on unexposed and exposed thin films of As2S3 deposited onto chromium‐coated glass substrates. We show the chemical changes on the surface and interface of As2S3 and chromium layers. The chromium layers are obtained by thermal evaporation, high‐frequency sputtering and electron beam evaporation. Chemical changes of the sample surface after laser irradiation are investigated. Exposure of As2S3 films results in photo‐induced oxidation of arsenic on the surface and formation of As2O3. It is established that the O 1s peak area on exposed samples decreases compared to the O 1s peak area on unexposed ones. This is related to desorption of As2O3 from the surface of exposed As2S3 layers. Another proof of desorption of As2O3 is the decrease of the As 3d/S 2p normalized peak area ratio on exposed As2S3 layers. The sulphur content on the surface remains unchanged after exposure of the samples, but its chemical surroundings change. An alteration of the chemical environment of As and Cr is observed at the As2S3/Cr interface, due to diffusion of chromium atoms through the interface into the As2S3 layer. This results in formation of an AsxCrySz compound at the As2S3/Cr interface, which dissolves with a lower rate. This hinders further etching of the metal coating during the photolithographic process employing Cr plates with inorganic photoresist based on vacuum deposited As2S3.
An XPS and SEMS study of silica sol‐gel/metal substrate interaction
Authors: Stoch A. , Stoch J. , Rakowska A. 
Published: May 2005

AbstractSome applications of ceramic materials are difficult because of the markedly differing lattice bonding characteristics of ceramic and metals. This ‘affinity barrier’ can be overcome by the modifying of structure and composition in the interphase region. In our work the silica sublayer was deposited by the sol‐gel method on metal implants prior to electrophoretical deposition of hydroxyapatite coatings to improve the oxidation resistance of the metal surface and the adhesion of apatite to metal during the annealing. The aim of this study is to determine changes in chemical state and structure of the coatings caused by thermal treatment for the better understanding of a relation between their composition and properties. Plates of titanium, WT 1‐0, FeCrNi stainless steel and of low‐carbon steel were covered with silica layer by the sol‐gel method. The coating on low‐carbon steel was produced by the deposition of silica sol‐gel directly on the metal or, the silica–titania opacified porcelain enamel was obtained by electrophoresis. In the case of direct deposition, below 400 °C, an amorphous layer was formed while at 800–900 °C for only 2‐4 min the dense, fine crystalline structure was obtained including small amount of silicates and iron scales. The silica–titania enamel was electrophoretically applied on low‐carbon steel pre‐coated with nickel. During annealing nickel is alloyed with iron and decreases oxygen transport towards iron decreasing the rate of FeO formation. The silica from the enamel reacts with FeO producing a small amount of silicates. Titania partially precipitates at the metal boundary in the form of the needle‐like crystals of FeTiO3, growing from the steel surface into the enamel. When stainless steel was annealed at 700 °C in air, the surface oxide was enriched in chromium and manganese while the silica surface was enriched in iron and manganese.
The microchemistry of interfaces in fiber‐reinforced ceramics and glasses
Authors: Schneider R. , Woltersdorf J. 
Published: May 2005

AbstractThe mechanical properties and the high‐temperature behaviour of fibre‐reinforced composites are controlled by both the microstructure and the microchemistry of fibre/matrix interlayers. For a C‐fibre reinforced SiC composite and various SiC (Nicalon)‐fibre reinforced Duran glasses, the composition of the interfacial layers, which are rich in different carbon modifications—due to either fibre precoating or subsequent solid state reactions—has been investigated by different techniques of analytical electron microscopy (AEM).
The investigation of instrumental and sample parameters as potential sources for affecting the reproducibility of isotopic ratio measurements in secondary ion mass spectrometry
Authors: Adriaens A. , Adams F. 
Published: May 2005

AbstractIn this study a number of instrumental and sample parameters were investigated as potential sources for affecting the reproducibility of isotopic ratio measurements in secondary ion mass spectrometry. The study consisted of examining the energy distributions of the individual isotopes using different parameter settings. This way, 70% of the observed isotopic variation could be ascribed to the setting of certain instrumental parameters such as the field aperture, the contrast diaphragm and the energy window width. In addition, the effects of differing crystal orientations in the sample and macroscopic surface characteristics upon the reproducibility were evaluated using imaging techniques.
Surface composition of machined leaded brass
Authors: Wu J. X. , Ji M. R. , Galeotti M. , Giusti A. M. , Rovida G. 
Published: May 2005

AbstractESCA and RBS were used to obtain quantitative information on the thickness and nature of the surface layers formed on machined brasses containing 1–3% lead. The results show that the brass surface is strongly enriched in lead. The amount of this element accumulated on the surface increases with increasing bulk concentration. Lead appears to be present as islands partially covering the brass surface and having variable thicknesses up to several hundred Å. The outermost layer of the islands is mainly a Pb hydroxycarbonate, under which PbO and Pb metal can be detected. Between the islands, the brass surface is covered by a layer of zinc oxide covering the CuZn metallic phase. The accumulation of Pb at the surface is attributable to a smearing effect caused by the machining cool.
ESCA investigation of SnOx films used as gas sensors
Authors: Sanjinés R. , Rosenfeld D. , Gozzo F. , Alméras Ph. , Perez L. , Lévy F. , Margaritondo G. , Schreiner W. H. 
Published: May 2005

AbstractThe electronic properties of amorphous and ion‐implanted polycrystalline SnO2 films have been studied using x‐ray photoemission spectromicroscopy. First, we analysed the degree of oxidation and the homogeneity of as‐deposited films. The SnO and SnO2 phases were identified from their valence band spectra rather than from the Sn 3d core level spectra. Then we studied the damage effects due to the implantation of Pd+ and Ga+ ions in polycrystalline films. The ion bombardment of SnO2 films results in drastic changes of valence‐band spectra which is correlated to compositional changes. Annealing in air at 600 °C for 4 h leads to complete recovery of radiation damage. However, after such thermal annealings, the film surface still contains a relatively high amount of SnO (5–10%).
AES and SAM studies of oxide formation on Inconel 600 at high temperatures
Authors: Alstrup N. C. , Langvad N. , Chorkendorff I. 
Published: May 2005

AbstractCharacterization of the oxide formed on a Ni‐based alloy (Inconel 600) at high temperatures has been carried out using AES and SAM combined with ion‐etched depth profiling. The oxidation experiment was done at 1000 °C, in atmospheric air and under mild (H2/H2O) oxidation conditions. In air, the resulting surface is highly inhomogeneous, featuring large Ni‐rich islands on top of a continuous Cr‐rich oxide layer. When the oxygen partial pressure (H2/H2O) was lowered, the Ni‐rich layer was not formed.
In search of the ultimate experiment for quantitative depth profile analysis in glow discharge optical emission spectrometry. Part II: Generalized method
Authors: Payling Richard 
Published: May 2005

AbstractThe current and voltage terms of the SIMR approach are combined with the pressure approach of BHP to derive an empirical equation that describes the relationship between recorded emission signal and current, voltage and pressure in a model‐independent way. To test the equation, an emission line from each of five different elements in up to five different matrices recorded in all three operational modes of the glow discharge lamp for thirty different values of current, voltage and pressure were combined to give an average of 114 data points per line. The equation was then fitted to the data through multiple linear regression to derive a best estimate of the separate contributions of current, voltage and pressure to intensity and emission yield. The results show that current, voltage and pressure all contribute significantly to the recorded signals and emission yields. Typically, emission yield is proportional to current, decreases as the square root of over‐voltage and increases linearly with pressure at low pressures but decreases exponentially at higher pressures.
Reflection–absorption Fourier transform infrared spectroscopy (RAIRS) study of the conformation and orientation of poly(amino acid) Langmuir–Blodgett films
Authors: Auduc‐Boyer N. , Stevenson I. , Duc Tran Mihn , Linossier I. , Gaillard F. 
Published: May 2005

AbstractA quantitative study by reflection–absorption infrared spectroscopy (RAIRS) on multilayer systems of Langmuir–Blodgett (LB) poly(amino acid) films has been carried out. Thickness measurements of monolayer and multilayer systems have been made and the results obtained by two well‐known equations have been compared. Evolution of the α‐helix conformation as a function of temperature in the case of polybenzyl aspartate (PBA) and polybenzyl glutamate LB systems has also been studied by RAIRS. Finally, a Fourier transform infrared transmission study on PBA LB multilayers as a function of temperature has allowed us to draw some conclusions on the orientation of the CO bonds (amide I) with respect to the dipping direction.
Caesium diffusion in sodium borosilicate glass studied by low‐energy ion scattering
Authors: Ceelen W. C. A. N. , Jacobs J.‐P. , Brongersma H. H. , Sengers E. G. F. , Janssen F. J. J. G. 
Published: May 2005

AbstractA new, time‐saving method to determine the diffusion coefficient of caesium in sodium borosilicate glass is presented. With low‐energy ion scattering (LEIS) the diffusion coefficient of caesium in this glass, where the main components are the same as those in nuclear waste glass, is determined in a wide temperature range (723–849 K). Compared to the conventional concentration couple method where the diffusion has to be studied over large distances (105 nm), it is shown that by using LEIS accurate measurements can be performed when diffusion takes place over distances of the order of 10 nm. Diffusion coefficients for caesium as low as 2.6 × 10−22 m2 s−1 are extracted from the measurements. This is a factor of 106 smaller than that measured with the concentration couple method for the same system and more than a factor of 10 smaller than diffusion coefficients for caesium determined in nuclear waste glasses by other techniques. At high temperatures the results of the different methods are in absolute agreement.
XPS studies of NO selective reduction catalysts after SO2 poisoning
Authors: Grzybek Teresa , Klinik Jerzy , Buczek Bronisław 
Published: May 2005

AbstractThe effect of an SO2–water vapour–air mixture on the structure of Fe3+‐, Cu2+‐, Co2+‐ or Ni2+‐active carbon catalysts used for selective catalytic reduction of NO with ammonia was studied by low‐temperature argon sorption and XPS. Active material reacted with oxidation products of SO2 to form appropriate sulphates. The reaction rate, expressed as surface sulphur‐to‐cation ratio, depended on the distribution of active material on the starting samples. The distribution of Fe3+, Cu2+, Ni2+ and Co2+ changed during the reaction as a result of movement of the cations into the porous system and was accompanied by some decrease in specific surface area and partial blocking of micropores.
On the role of molecular photofragmentation during depth profiling of tantalum oxide layers by laser SNMS
Authors: Wucher A. , Franzreb K. , Mathieu H.‐J. , Landolt D. 
Published: May 2005

AbstractDepth profile analysis of an ultrathin native oxide layer grown on tantalum metal was performed by time‐of‐flight sputtered neutral mass spectrometry (SNMS) with laser post‐ionization and 11.6 keV Ga+ ion bombardment. Ionization of the sputtered neutral particles was achieved by non‐resonant multiphoton absorption from a pulsed excimer laser operated at 248nm. Particular emphasis was put on the signals of sputtered neutral Ta atoms and TaO molecules, which are interpreted quantitatively by means of a simple model proposed earlier describing the formation probability of sputtered oxide molecules. It is shown that the measured Ta signal contains a considerable fraction of fragmentation products produced by photodissociation of sputtered TaO. From the results, the time‐dependent surface stoichiometry as well as the relative probabilities for photoionization and photofragmentation of TaO are evaluated.
Quantitative surface analysis of styrene–butadiene copolymers using time‐of‐flight secondary ion mass spectrometry
Authors: Weng L. T. , Bertrand P. , Lauer W. , Zimmer R. , Busetti S. 
Published: May 2005

AbstractThe potential applicability of time‐of‐flight secondary ion mass spectrometry (ToF SIMS) as an independent quantitative technique has been studied using a more complicated copolymer system: styrene‐butadiene copolymer. The complication of this system is that the characteristic SIMS peaks are not unique to each monomer. It has been found that quantitative information can be obtained from the relative SIMS intensities of certain characteristic peaks, i.e. m/z = 63, 89, 103 and 115 for styrene and 53, 67 and 79 for butadiene. In particular, the intensity ratios A/(A + B), where A and B represent, respectively, the above characteristic peaks of styrene and butadiene, have been found to be linearly related to the bulk styrene molar concentration. These results suggest that a sensitivity factor that is constant and independent of the copolymer composition can be defined for these peaks. However, this conclusion cannot be generalized for other SIMS peaks, such as m/z = 77, 91 and 105.
Curve fitting of Cr 2p photoelectron spectra of Cr2O3 and CrF3
Authors: Grohmann I. , Kemnitz E. , Lippitz A. , Unger W. E. S. 
Published: May 2005

AbstractChromium (III) 2p photoelectron spectra show strong satellites on the high‐binding‐energy side of the main photoelectron peaks. In the case of Cr 2p spectra, the satellite of the Cr 2p3/2 peak strongly overlaps the Cr 2p1/2 peak. As a result, a virtual three‐peak spectrum is obtained. In order to analyse the spectral features of the Cr 2p photoelectron peaks, we propose a fitting formalism for Cr(III) 2p spectra that is consistent with a relaxation model. This model allows for the possibility of two different final‐state screening conditions of the photoinduced core hole. Considering these two final states, Cr 2p spectra basically can be interpreted by a superposition of two 2p doublets. X‐ray contributions arising from the Kα3,4 lines were also taken into account, as well as the existence of OH groups on the surface of Cr2O3 samples. Additionally, a rather pragmatic approach for fitting the Cr L3M23V Auger spectral region was used to obtain further spectral parameters (e.g. α′) that do not depend on charging.
The diffusion of gases and vapors in rigid PVC
Authors: Berens A. R. 
Published: May 2005

AbstractGravimetric sorption rate measurements have been carried out for (CO2, H2), and ten C1‐C6 organic vapors at low concentrations (≤ 0.2%) in PVC films and uniform‐particle powders at 30°C. The dominant transport process in all cases appears to be Fickian diffusion. A distinguishable contribution of relaxation‐controlled swelling was observed for the more soluble vapors, such as acetone and benzene. A significant contribution of surface adsorption to the total sorption process was detected only for the n‐alkanes, among the penetrants studied. Diffusion coefficients, determined from half‐sorption times and polymer dimensions, range from 4 × 10 −8 cm2/sec for H2O to 1.5 × 10 −15 cm2/sec for n‐hexane. Diffusivities determined in this study, in combination with those for gases reported by Tikhomorov, et al. (Makromol. Chem. 118 177 (1968)), define a continuous curve, covering more than nine orders of magnitude, when plotted as a function of the molar volume constant, b, of the van der Waals equation of state for gases and vapors.
Effect of phosphate esters on PVC flammability from a multi‐test viewpoint
Authors: Keeney C. N. 
Published: May 2005

AbstractMany tests have been developed to provide relative flame/smoke data. In spite of the proliferation of such tests and test equipment, many chemical and polymer producers, as well as fabricators, use only one technique to evaluate the flame/smoke properties of a polymer system. This paper demonstrates the importance of multi‐method testing to rate the efect of phosphate esters and various fillers on PVC flammability and smoke generation.
Improving the stiffness of commingled thermoplastics
Authors: Schadler Linda S. , Gobran Riad , Park Sung Chul , Gleason Michael 
Published: May 2005

AbstractOne of the limitations of commingled recycled plastics is their low flexural modulus, resulting from both the linear nature of thermoplastics and the incompatibility of the polymer phases. The goal of this study was to increase the flexural modulus of commingled recycled plastics by the addition of small amounts of polyester that acted both as a compatibilizer and a crosslinking agent. It was found that the increase in flexural modulus was caused by the unsaturated polyester acting as a filler, the improvement in compatibility of the phases, and the crosslinking of the commingled plastics. The increase was offset somewhat by a decrease in crystallinity of the phases.