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Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Batterie lithium, Lithium battery, Cathode, Cátodo, Cycle charge décharge, Discharge charge cycle, Ciclo carga descarga, Diffractométrie RX, X ray diffractometry, Difractometría RX, Lithium Nickel Cobalt Oxyde, Lithium Nickel Cobalt Oxides, Litio Niquel Cobalto Óxido, Matériau électrode, Electrode material, Material electrodo, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Revêtement protecteur, Protective coatings, Revestimiento protector, Résonance paramagnétique électronique, Electron paramagnetic resonance, Resonancia paramagnética electrónica, Spectrométrie IR, Infrared spectrometry, Espectrometría IR, Stabilité, Stability, Estabilidad, Traitement surface, Surface treatment, Tratamiento superficie, Cathode materials, Coating technique, Cycling stability, Lithium ion batteries, and Structural characterisation

We provide data on the changes in structure and composition of commercial LiNi0.8Co0.2O2 electrode materials for lithium-ion batteries occurring after surface coating with two types of metal oxides: electrochemically active LiCoO2 and inactive MgO. XRD analysis, SEM images, IR spectroscopy and EPR of low-spin Ni3+ ions were carried out for structural characterisation of coated LiNi0.8Co0.2O2 electrodes. Surface modification with LiCoO2was found to be a more effective route for improving the cycling stability of LiNi0.8Co0.2O2. The favourable effect of LiCoO2-coating was connected with an enhanced stability of the bulk composition and reduction of electrode/electrolyte interaction.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Batterie électrique, Electric batteries, Cobalt oxyde, Cobalt oxide, Cobalto óxido, Lithium oxyde, Lithium oxide, Litio óxido, Traitement surface, Surface treatment, Tratamiento superficie, LiCoO2, Lithium ion batteries, Soakage, and Spontaneous reactions

Spontaneous reactions have been observed between LiCoO2 and electrolyte solvent for lithium ion batteries by characterizing the structural and/or components of the generated species in their gas, liquid and solid states. It is shown that surface coating cannot prevent the dissolution of Li and Co ions from LiCoO2 or the structural degradation of LiCoO2. However, surface modification can suppress the loss of oxygen from LiCoO2. Based on these results, another important aspect of the performance improvement mechanism by surface modification to LiCoO2 and the limitation of surface modification are proposed.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Azote Nitrure, Nitrogen Nitrides, Nitrógeno Nitruro, Batterie lithium, Lithium battery, Couche mince, Thin film, Capa fina, Electrolyte solide, Solid electrolyte, Electrólito sólido, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Préparation, Preparation, Preparación, Spectrométrie Raman, Raman spectrometry, Espectrometría Raman, Spectrométrie photoélectron, Photoelectron spectrometry, Espectrometría fotoelectrón, Traitement surface, Surface treatment, Tratamiento superficie, Carbon, Lithium-ion batteries, Solid electrolyte interface, Surface modification, and Thin-film electrode

Carbonaceous thin-film electrodes were modified by nitrogen trifluoride (NF3) plasma, and surface-modified carbonaceous thin-film electrodes were obtained and investigated by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES). Their chemical composition, degree of fluorination, and chemical bonding were investigated. The effects of surface modification on the anode reaction of lithium-ion batteries were examined. The electrochemical properties of the resultant thin-film electrodes were investigated by cyclic voltammetry using a three-electrode electrochemical cell. The cyclic voltammograms showed that the fluorine atoms on the surface suppressed the reductive decomposition of ethylene carbonate.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Batterie lithium, Lithium battery, Cathode, Cátodo, Matériau revêtement, Coating material, Material revestimiento, Matériau électrode, Electrode material, Material electrodo, Nanoparticule, Nanoparticle, Nanopartícula, Procédé sol gel, Sol gel process, Procedimiento sol gel, Titane oxyde, Titanium oxide, Titanio óxido, Traitement surface, Surface treatment, Tratamiento superficie, Zirconium oxyde, Zirconium oxide, Zirconio óxido, Coated LiCoO2, Coated cathodes, Lithium-ion battery, Mechano-thermal coating, Nanoparticles, and Sol-gel coating

Surface modification as a method for enhancing the cyclability of LiCoO2 cathodes is reviewed. The performances of TiO2 and ZrO2, and their mixed oxide, ZrTiO4, as coating materials, are compared. Coating techniques such as sol-gel and mechano-thermal processes are described. Structural data and morphology of the oxide-coated LiCoO2 are correlated with electrochemical behavior. Their enhanced cyclability is attributed to the suppression of the cycle-limiting phase transitions accompanying the charge-discharge processes. The higher cyclability of the mixed oxide-coated cathodes over those coated with the corresponding individual oxides is also demonstrated. It is also shown that the nature of the core material and the sol-gel precursors for the coatings play a definitive role in the electrochemical behavior of the coated cathode materials.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Basse température, Low temperature, Baja temperatura, Fibre carbone, Carbon fiber, Fibra carbón, Impédance, Impedance, Impedancia, Lithium, Litio, Mesure, Measurement, Medida, Mésophase, Mesophase, Mesofase, Traitement surface, Surface treatment, Tratamiento superficie, Double layer capacity, Impedance analysis, Li insertion/extraction, Low temperature carbon fiber, and Surface modification

Surface modifications with three different procedures were performed on an integrated felt of mesophase carbon fiber (MCF) fired at 600 °C. The surface modification procedures were (1) heating in acetylene black powder under a low pressure of oxygen (MOT), (2) vacuum deposition of Ag film on the fiber surface and (3) vacuum deposition of Ag film on the fiber, followed by heating under low pressure of oxygen. The performance of Li insertion/extraction reaction was found improved by any of these modification treatments. The cause of the improvement was examined mainly with impedance spectroscopy analysis (EIS). EIS spectra revealed that both the film resistance and the charge-transfer resistance were decreased remarkably by these surface modifications. Among the three modification procedures, MOT revealed the best improving effect. By comparing the EIS data with the results obtained from the double layer capacity measurement, we concluded that the major cause of the increase in the reaction rate is the activation of the reaction site.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Appareils de production et de conversion d'énergie: énergie thermique, énergie électrique, énergie mécanique, etc, Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc, Piles à combustible, Fuel cells, Acier inoxydable, Stainless steel, Acero inoxidable, Bipolaire, Bipolar, Corrosion électrochimique, Electrochemical corrosion, Corrosión electroquímica, Coût, Costs, Coste, Electrolyte polymère, Polymer electrolytes, Performance, Rendimiento, Pile combustible, Fuel cell, Pila combustión, Plaque, Plate, Placa, Résistance corrosion, Corrosion resistance, Resistencia corrosión, Résistivité électrique, Electric resistivity, Resistividad eléctrica, Traitement surface, Surface treatment, Tratamiento superficie, Bipolar plate, Corrosion-resistance, and Electrical resistance

Thin sheets of stainless steel are low-cost material for fuel cell components that can be easily formed to yield compact volume. But corrosion of the stainless steel bipolar plates is a problem in the PEMFC. Corrosion affects the performance and cell life of a fuel cell. The goal of this study is to find out appropriate surface treatment technology to protect the stainless steel bipolar plates against electrochemical corrosion. The feasible surface treatment process should be able to make significant improvement on the corrosion-resistance and the electrical resistance at a reasonable cost. After the treatment, the surface composition and/or the surface morphology may be modified. The modification of the surface composition may improve the corrosion-resistance of the metallic bipolar plate. The corrosion rate is determined by linear-polarization method from the polarization curve. The differences in polarization behaviors are attributed to a surface treated layer. The electrical resistance is the other factor which may affect the performance of the fuel cell. A smoother surface may reduce the interfacial resistance. The treated layer is a passive film. The thickness of the passive film after the surface treatment is thinner and the surface resistance is reduced.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Batterie acide plomb, Lead acid batteries, Cycle charge décharge, Discharge charge cycle, Ciclo carga descarga, Performance, Rendimiento, Soupape, Valve, Válvula, Séparateur batterie, Battery separators, Traitement surface, Surface treatment, Tratamiento superficie, Charge and discharge of LA batteries, Electrolyte stratification, Lead-acid battery, Modified AGM, and VRLAB

A new modified AGM (MAGM) separator for VRLA batteries and the respective technology for its production have been developed. The new product is obtained by processing absorbent glass mat (AGM) separator with polymer emulsion, which is adsorbed onto the surface of the glass fibres and concentrates at the sites of contact between the fibres. Thus, a continuous porous network of interconnected glass fibres is formed. The two surfaces of the AGM sheet are treated with polymer emulsion of different concentration in view of the different processes that take place at the positive and the negative plates, respectively. As a result of the above treatment the surface properties of the AGM are modified to balance hydrophobic/hydrophilic properties. The MAGM separator has improved tensile strength as compared to untreated AGM, a slightly reduced H2SO4 absorption and wicking rate, and increased chemical and thermal stability. It does not disperse in H2SO4 solution as does AGM. The influence of the MAGM separator on the processes in the valve-regulated lead-acid cell has been investigated. An experimental method has been elaborated and used to establish the existence of horizontal electrolyte stratification between the plates. This stratification is a result of the different processes that occur at the two types of plates as well as of the resistance that the ion flows of H2SO4 and H2O have to overcome when passing through the separator. In VRLA batteries, their movement is impeded by the AGM separator, which reduces the available capacity of the battery. The effect of the MAGM separator on the concentration of H2SO4 at the two separator interfaces during charge, discharge, open circuit (OC) and on cycling is investigated. MAGM influences the processes in the cells in such a way that the differences in H2SO4 concentration between the two types of plates are eliminated. These effects of the MAGM separator result in an increase of the available capacity of the battery on cycling and float service, which leads to a substantial increase in VRLA battery life. Moreover, MAGM improves the efficiency of the oxygen cycle in the cells and thus the water loss is reduced. Besides, MAGM separators reduce the differences in cell voltage when numerous cells are connected in long strings.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Produits de revêtement. Peintures, vernis et encres, Coatings. Paints, varnishes and inks, Formation et durcissement des feuils, propriétés, essais, Film formation and curing, properties, testing, Assemblage moléculaire, Molecular assembly, Ensamble molecular, Autoassemblage, Self assembly, Autoensamble, Matériau revêtement, Coating material, Material revestimiento, Nanoparticule, Nanoparticle, Nanopartícula, Nanostructure, Nanoestructura, Peinturage, Painting process, Pintura de brocha gorda, Procédé sol gel, Sol gel process, Procedimiento sol gel, Protection corrosion, Corrosion protection, Protección corrosión, Préparation surface, Surface preparation, Preparación superficie, Silice, Silica, Sílice, Traitement surface, Surface treatment, and Tratamiento superficie

Nanostructured surface treatment coatings based on the Self-assembled Nanophase Particle (SNAP) approach were investigated as potential replacement for chromate-based surface treatments on aircraft aluminum alloys. In the traditional sol-gel method, hydrolysis-condensation processes are followed by condensation polymerization upon film application. This process sequence provides a low temperature route to the preparation if thin coatings which are readily applied to most metallic substrates. The recent discovery of a method of forming functionalized silica nanoparticles in situ in an aqueous sol-gel process, and then cross-linking the nanoparticles to form a thin film, is an excellent example of a nanoscience approach to coatings. This Self-assembled Nanophase Particle (SNAP) process can be used to form thin, dense protective organic surface treatment coatings on Al aerospace alloys. The ability to design coating components from the molecular level upward offers tremendous potential for creating multifunctional coatings. The important components of Al alloy corrosion inhibition by chromate are storage and release of CrVI species, inhibition of cathodic reactions (primarily oxygen reduction), and inhibition of attack at active sites in the alloy. Unlike chromate-based treatments, current SNAP coatings provide barrier-type corrosion resistance but do not have the ability to leach corrosion inhibitors upon coating damage and minimize corrosion of the unprotected area. In this study, organic inhibitors were tested for corrosion protection of aluminum alloys in combination with the (SNAP). Scanning Vibrating Electrode Technique, anodic polarization, electrochemical impedance spectroscopy, and salt spray test were used to study this new approach for chromate replacement.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Produits de revêtement. Peintures, vernis et encres, Coatings. Paints, varnishes and inks, Constituants, formulation, Components, formulation, Aluminium alliage, Aluminium alloy, Aluminio aleación, Couche mince, Thin film, Capa fina, Dégraissage, Degreasing, Desengrase, Formulation, Formulación, Matériau modifié, Modified material, Material modificado, Matériau revêtement, Coating material, Material revestimiento, Méthode électrochimique, Electrochemical method, Método electroquímico, Nanoparticule, Nanoparticle, Nanopartícula, Peinture anticorrosion, Anticorrosive paint, Pintura anticorrosión, Protection corrosion, Corrosion protection, Protección corrosión, Préparation surface, Surface preparation, Preparación superficie, Silane organique, Organic silane, Silano orgánico, Silice, Silica, Sílice, Subjectile, Substrate(coating), Subsrato, Traitement surface, Surface treatment, and Tratamiento superficie

Silane surface treatments have been developed as an alternative for toxic and carcinogenic chromate-based treatments for years. It is consistently observed that ultra-thin silane films offer excellent corrosion protection as well as paint adhesion to metals. The silane performance is comparable to, or in some cases better than, that of chromate layers. The most recent studies also showed that the silane films can be thickened and strengthened by loading of a small amount of nanoparticles such as silica and alumina into the films resulting in enhanced corrosion protection of aluminum alloys.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Produits de revêtement. Peintures, vernis et encres, Coatings. Paints, varnishes and inks, Technologie d'application et de séchage, Technology of painting and drying, Acrylique dérivé polymère, Acrylic polymer, Acrilico derivado polímero, Epoxyde résine, Epoxy resin, Epóxido resina, Essai brouillard salin, Salt spray test, Ensayo en niebla salina, Essai corrosion, Corrosion test, Ensayo corrosión, Formulation, Formulación, Industrie aérospatiale, Aerospace industry, Industria aeroespacial, Liant, Binders, Ligante, Matériau revêtement, Coating material, Material revestimiento, Méthode électrochimique, Electrochemical method, Método electroquímico, Peinturage, Painting process, Pintura de brocha gorda, Peinture primaire, Primer paint, Pintura primaria, Performance, Rendimiento, Phosphatation, Phosphating, Fosfatación, Protection corrosion, Corrosion protection, Protección corrosión, Préparation surface, Surface preparation, Preparación superficie, Prétraitement, Pretreatment, Pretratamiento, Revêtement anticorrosion, Corrosion protective coatings, Silane organique, Organic silane, Silano orgánico, Traitement surface, Surface treatment, and Tratamiento superficie

A novel chrome-free surface pretreatment and primer combined in one-step application for aircraft coating is described. First, a high-solids solvent-borne non-chromate epoxy primer (referred to as CD112) is developed. The formulation of CD112 system is based on epoxy/polyamide chemistry, Adheron's proprietary anti-corrosive pigments, and a tightly packed passivating film made of fillers with different geometric shapes. The protective performance of CD112 has been tested at three independent laboratories and shown to pass a 3000 h salt spray resistance, compatible to its chromate counterpart, on both 2024-T3 Clad/Alodine 1000 and 7075-T6 Clad/Alodine 1000 aluminum alloys. Second, a chrome-free acrylic emulsion for surface pretreatment of aluminum alloys is formulated, comprising an ∼60 nm particle size of acrylic resins, metal-chelating reagents, organofunctional silanes, and non-toxic anti-corrosive pigments. An ∼ 1 μm dry film is processed on 2024-T3 Bare Al panel (referred to as 2024-T3 Bare/AFP) and then coated with MIL-PRF-23377 Type I approved chromate-based primer. The electrochemical impedance spectroscopy (EIS) data indicate that 2024-T3 Bare/AFP show about 100 times more resistance than 2024-T3 Bare/Alodine 1200. Third, two in situ phosphatizing reagents (ISPRs) were selected to formulate the in situ phosphatizing coating (ISPC) aerospace primers of MIL-PRF-23377 class N, and to promote the formation of a metal-phosphate layer at the molecular level. The ISPC technique combines a chrome-free surface pre-treatment and primer into a single-step application. The EIS data demonstrate that the ISPC CD112 primer on untreated 2024-T3 Al coupons shows 10-100 times more resistance than the control CD112 primer on 2024-T3 Bare/Alodine 1200. The chemistry of the simultaneous reaction of ISPRs catalyzing the curing of the paint film and forming the metal-phosphate layer at the interface will be illustrated.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Batterie lithium, Lithium batteries, Caractéristique électrochimique, Electrochemical characteristic, Característica electroquímica, Lithium oxyde, Lithium oxide, Litio óxido, Manganèse oxyde, Manganese oxides, Manganeso óxido, Matériau électrode, Electrode material, Material electrodo, Spinelle, Spinel, Espinela, Thiophène dérivé polymère, Thiophene derivative polymer, Tiofeno derivado polímero, Traitement surface, Surface treatment, Tratamiento superficie, Conducting polymer, Li-ion battery, Non-stoichiometric spinet, and pEDOT

This study reports the electrochemical characterization of non-stoichiometric LiMn2O4 spinels (commercial and home-made via the sol-gel route) covered by poly(3,4-ethylenedioxythiophene) (pEDOT) chemically grown on the oxide particle surface and of spinels without polymer covering for use in lithium-ion batteries. The results demonstrate that the pEDOT covered spinels can be suitable electrode materials without addition of conducting carbon, and that they display a slightly higher stability upon cycling than the corresponding spinels without pEDOT covering, indicating a moderate barrier effect of pEDOT which protects the inorganic particles from degradation.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Produits de revêtement. Peintures, vernis et encres, Coatings. Paints, varnishes and inks, Formation et durcissement des feuils, propriétés, essais, Film formation and curing, properties, testing, Propriété surface, Surface properties, Propiedad superficie, Adhérence, Adhesion, Adherencia, Energie surface, Surface energy, Energía superficie, Faisceau ionique, Ion beam, Haz iónico, Formulation, Formulación, Hydrophilie, Hydrophily, Hidrofilia, Liant, Binders, Ligante, Matériau revêtement, Coating material, Material revestimiento, Mouillabilité, Wettability, Remojabilidad, Traitement surface, Surface treatment, and Tratamiento superficie

The wettability and adhesion of various polymers were improved using ion-assisted reaction (IAR) method, in which the polymer surfaces were irradiated by energetic ions in a reactive gas environment. The addition of new polar groups on polymer surfaces and permanent wettable polymer surfaces (water contact angle below 30° and surface free energy 60-70 mJ/m2) have been accomplished by IAR treatment. The changes in wettability and surface free energy were critically dependent on the ion dose, the ion beam energy and the flow rate of the reactive gas. Improvements in wettability and surface free energy are primarily attributed to the increase of polar components due to the formation of polar groups such as -(C=O)-, -(C=O)-O-, -(C-O)-, etc. The characteristics of the IAR treatment have been reviewed, with outstanding results regarding the wettability and adhesion of various polymers from polyolefin to fluoropolymers.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Produits de revêtement. Peintures, vernis et encres, Coatings. Paints, varnishes and inks, Formation et durcissement des feuils, propriétés, essais, Film formation and curing, properties, testing, Bronze, Bronce, Extérieur, Outer, Exterior, Liant, Binders, Ligante, Matériau revêtement, Coating material, Material revestimiento, Méthode électrochimique, Electrochemical method, Método electroquímico, Peinturage, Painting process, Pintura de brocha gorda, Performance, Rendimiento, Protection corrosion, Corrosion protection, Protección corrosión, Protection rayonnement, Radiation protection, Protección radiación, Préparation surface, Surface preparation, Preparación superficie, Revêtement protecteur, Protective coatings, Revestimiento protector, Sculpture, Escultura, Subjectile, Substrate(coating), Subsrato, Traitement surface, Surface treatment, and Tratamiento superficie

Outdoor bronze sculpture is vulnerable to acid rain-induced corrosion and the present protection schemes utilized by conservators do not provide adequate protection under many circumstances. To replace the current most common clear bronze protection systems, wax or Incralac® with a top coat of wax, work is underway to develop different options for conservators that include new longer-lasting, more durable systems having improved corrosion protection. The use of improved matrix binders based on fluorocarbon polymers, the use of nano-sized TiO2 for UV absorption, and the extended use of UVAs and HALS are under examination in a search for improved UV resistance and longer lived corrosion protection in clear bronze coatings. Advanced spectroscopic and electrochemical methods are being used to characterize new coatings candidates with respect to UV resistance and corrosion resistance.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Produits de revêtement. Peintures, vernis et encres, Coatings. Paints, varnishes and inks, Formation et durcissement des feuils, propriétés, essais, Film formation and curing, properties, testing, Conservation, Conservación, Cristallisation, Crystallization, Cristalización, Essai mécanique, Mechanical test, Ensayo mecánico, Essai vieillissement accéléré, Accelerated aging test, Ensayo envejecimiento acelerado, Matériau poreux, Porous material, Material poroso, Pierre, Stone, Piedra, Porosimétrie mercure, Mercury porosimetry, Porosimetría mercurio, Revêtement protecteur, Protective coatings, Revestimiento protector, Sodium chlorure, Sodium chloride, Sodio cloruro, Thermodynamique, Thermodynamics, Termodinámica, Traitement surface, Surface treatment, and Tratamiento superficie

Susceptibility of stone to salt decay is directly related to its microstructural and mechanical characteristics. In the present work, a porous stone from a quarry in Cyprus was examined. Samples of this stone were consolidated and protected with certain conservation materials. The modification of microstructural characteristics of the stone was evaluated by mercury intrusion porosimetry, while its mechanical characteristics were measured by compressive and bending strength tests. From these data, the susceptibility of Cyprus stone to salt (NaCl) decay was estimated. The values of crystallization pressure of NaCl were calculated and compared to the experimentally measured compressive and tensile strength of the stone, in order to examine the probability of stone disruption due to salt crystallization. The development of the phenomenon after coarse pores' filling with crystals, i.e. crystallization of salts in capillaries or mechanical failure of the stone, was determined by thermodynamic analysis. Additionally, artificial weathering tests of marine salt spray were performed for the evaluation of stone's durability after the conservation. The treated stone proved to be resistant to salt decay, as it presented ameliorated microstructural and mechanical characteristics, concerning decay due to soluble salt crystallization. The most possible thermodynamic scenario was small pores repletion with crystals, avoiding mechanical failure of the stone.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Produits de revêtement. Peintures, vernis et encres, Coatings. Paints, varnishes and inks, Généralités, General, Calcaire, Limestone, Calcáreo, Matériau revêtement, Coating material, Material revestimiento, Pierre, Stone, Piedra, Pollution air, Air pollution, Contaminación aire, Résistance superficielle, Surface resistance, Resistencia superficial, Soufre dioxyde, Sulfur dioxide, Dióxido sulfúrico, Traitement surface, Surface treatment, Tratamiento superficie, Vitesse dépôt, Deposition rate, and Velocidad deposición

NCPTT's Materials Research program studies the effects of air pollution on cultural resources. Air pollution, generated from man-made sources through the burning of fossil fuels, can affect our monuments, buildings and historic sites. The goals of our work include understanding the how air pollution interacts with the material fabric of cultural resources and what we can do to minimize damage from air pollution through the use of organic coatings and treatments. In this paper, we concentrate on the evaluation of organic coating treatments on calcareous stone upon exposure to sulfur dioxide environments. We present an overview of a unique, custom-built recirculating exposure chamber used to measure sulfur dioxide deposition on untreated and treated calcareous stone. We present the preliminary results of sulfur dioxide uptake on Salem limestone samples treated with experimental water and pollutant repellent coating systems under development by DuPont Corporation. We discuss the experimental design for expansion of this study to a variety of organic coatings used in architectural and objects conservation.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Métal alcalin Ion, Alkali metal Ions, Metal alcalino Ión, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Accumulateur électrolyte organique, Organic electrolyte storage battery, Acumulador electrolito orgánico, Batterie métal non métal, Metal nonmetal batteries, Batterie électrique, Electric batteries, Composé insertion au graphite, Graphite intercalation compounds, Electrolyte solide, Solid electrolyte, Electrólito sólido, Evaluation performance, Performance evaluation, Evaluación prestación, Interphase, Interfase, Lithium ion, Litio ión, Matériau électrode, Electrode material, Material electrodo, Structure interface, Interface structure, Estructura interfaz, Traitement surface, Surface treatment, Tratamiento superficie, Traitement thermique, Heat treatment, and Tratamiento térmico

Lithium intercalation and deintercalation processes occur through solid electrolyte interfaces (SEIs) on the zigzag and armchair faces of graphite. Such SEIs are formed by reaction of surface groups on the graphite with lithium upon charging. The nature of this interface to a large extent determines the reversible and irreversible capacities of the graphite. We have investigated the influence of mild oxidation of samples of natural graphite and carbon nanotubes on the surface characteristics of the films formed on these materials upon lithium intercalation. The surface groups formed upon oxidation have been characterized using Fourier transform infrared (FT-IR) spectroscopy. The reversible and irreversible capacities of the thermally oxidized samples are discussed in terms of the surface film composition as well as enhanced surface area that contributes to increased number of sites for lithium intercalation.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Métal alcalin Ion, Alkali metal Ions, Metal alcalino Ión, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Accumulateur électrolyte organique, Organic electrolyte storage battery, Acumulador electrolito orgánico, Batterie métal non métal, Metal nonmetal batteries, Batterie électrique, Electric batteries, Carbone dioxyde, Carbon dioxide, Carbono dióxido, Composé insertion au graphite, Graphite intercalation compounds, Electrolyte solide, Solid electrolyte, Electrólito sólido, Evaluation performance, Performance evaluation, Evaluación prestación, Interphase, Interfase, Lithium ion, Litio ión, Matériau électrode, Electrode material, Material electrodo, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Structure interface, Interface structure, Estructura interfaz, Traitement surface, Surface treatment, Tratamiento superficie, Traitement thermique, Heat treatment, and Tratamiento térmico

A novel, quite flexible strategy for the surface pre-treatment of graphite anodes for lithium ion cells has been developed. The treatment involves a high temperature cleaning step in inert Ar atmosphere before treatment with gaseous reactants such as CO2 or O2. The effects of surface modification on the formation of the solid electrolyte interphase (SEI) and the corresponding irreversible charge losses are discussed by way of several examples. Morphology changes due to burn-off of carbon are particularly highlighted.

Electrical engineering, Electrotechnique, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Electroénergétique, Electrical power engineering, Conversion directe et accumulation d'énergie, Direct energy conversion and energy accumulation, Conversion électrochimique: piles et accumulateurs électrochimiques, piles à combustibles, Electrochemical conversion: primary and secondary batteries, fuel cells, Métal alcalin Ion, Alkali metal Ions, Metal alcalino Ión, Accumulateur électrochimique, Secondary cell, Acumulador electroquímico, Accumulateur électrolyte organique, Organic electrolyte storage battery, Acumulador electrolito orgánico, Batterie métal non métal, Metal nonmetal batteries, Batterie électrique, Electric batteries, Coke brai, Pitch coke, Coque brea, Composé insertion, Intercalation compound, Compuesto inserción, Etat solide, Solid state, Estado sólido, Evaluation performance, Performance evaluation, Evaluación prestación, Lithium 7, Lithium ion, Litio ión, Matériau électrode, Electrode material, Material electrodo, Spectrométrie RMN, NMR spectrometry, Espectrometría RMN, Structure surface, Surface structure, Estructura superficie, Traitement surface, Surface treatment, Tratamiento superficie, Traitement thermique, Heat treatment, and Tratamiento térmico

Lithium intercalation into coke carbon modified with mesophase-pitch and heat-treated at 800, 1000, and 3000°C was observed using solid-state 7Li-nuclear magnetic resonance (7Li-NMR) spectroscopy. It was found that the fully lithiated state charged to 0 V in the modified coke heat-treated at 3000°C showed a peak at about 45 ppm; on the other hand, two peaks appeared at about 45 and 16-17 ppm in the modified coke heat-treated below 1000°C. The peak appearing at 45 ppm indicated that Li-GIC is present in the first stage, and the peak at about 16-17 ppm indicated that the lithium stored in the modified part has an ionic character greater than in the coke part and is not a lithium cluster. The lithiated states charged to 0.1 and 0.2 V and discharged to 0.1, 0.2 and 1.5 V from the charged state (0 V) are also described.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Méthodes. Procédés. Technologies, Methods. Procedures. Technologies, Techniques d'immobilisation, Immobilization techniques, Immobilisation de cellules entières et d'organites cellulaires, Immobilization of organelles and whole cells, Antigène HBs, Hepatitis B surface antigen, Antígeno HBs, Distribution, Distribución, Immobilisation, Immobilization, Inmovilización, Immunoglobuline, Immunoglobulins, Inmunoglobulina, Méthode immunoenzymatique, Enzyme immunoassay, Método inmunoenzimático, Réaction dirigée, Template reaction, Reacción dirigida, Science matériau, Material science, Ciencia material, Spectrométrie photoélectron, Photoelectron spectrometry, Espectrometría fotoelectrón, Traitement surface, Surface treatment, and Tratamiento superficie

Immobilization and distribution properties of the polyclonal antibodies to hepatitis B surface antigen (anti-HBsAg) onto 3-aminopropyltriethoxylsilane (APTES) modified silicon wafer surfaces under two different kinds of coupling conditions were investigated using atomic force microscopy (AFM). Enzyme immunoassay (EIA) and X-ray photoelectric spectroscopy (XPS) were also used as the complimentary techniques to quantify a NH2-terminated siloxane monolayer and a antibody layer. Anti-HBsAg antibodies were site-directly immobilized onto the APTES modified surface: (1) in acetate buffer of pH 5.2 for 3 days at 4°C and (2) in acetate buffer of pH 5.2 containing 5 mM NaBH4 for 12 h. via aldehydes generated on the carbohydrate side chains at the C-terminal of IgG using periodate (NaIO4)-oxidized reactions.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie de surface, Surface physical chemistry, Généralités, appareillage, General, apparatus, Alkyle, Alkyl, Alquilo, Chimisorption, Chemisorption, Adsorción química, Composé minéral, Inorganic compound, Compuesto inorgánico, Composé organique, Organic compounds, Compuesto orgánico, Cristal, Crystals, Modification, Modificación, Spectrométrie IR, Infrared spectrometry, Espectrometría IR, Structure surface, Surface structure, Estructura superficie, Topaze, Topaz, Topacio, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement surface, Surface treatment, and Tratamiento superficie

In chemisorption, one is typically faced with the problem that the two-dimensional structure of the organic layer does not match the structure of the inorganic substrate. This work describes the first steps toward an induced epitaxial correlation of organic compounds on an inorganic surface. The idea of this work was to use a single crystal with a two-dimensional surface structure, Topaz (001), that matches an alkyl chain lattice better than existing substrates. X-ray reflectivity and FTIR experiments prove the surface modification of the Topaz, which is probably an etherification of the reactive OH-groups on the Topaz (001) surface.