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Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Atomic molecular physics, Physique atomique et moléculaire, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Matériau poreux, Porous material, Material poroso, Alumine, Alumina, Alúmina, Chimie, Chemistry, Química, Cinétique, Kinetics, Cinética, Colorant, Dyes, Colorante, Composé de métal de transition, Transition element compounds, Croissance, Growth, Crecimiento, Dispositif, Device, Dispositivo, Durée vie, Lifetime, Tiempo vida, Dépôt, Deposition, Depósito, Efficacité, Efficiency, Eficacia, Electron, Electrons, Electrón, Energie, Energy, Energía, Epaisseur couche, Layer thickness, Espesor capa, Etat excité, Excited state, Estado excitado, Etat solide, Solid state, Estado sólido, Goutte, Drop, Gota, Modèle, Models, Modelo, Nanoporosité, Nanoporosity, Nanoporosidad, Oxyde d'aluminium, Aluminium oxide, Aluminio óxido, Oxyde de titane, Titanium oxide, Titanio óxido, Phénomène transitoire, Transients, Fenómeno transitorio, Recombinaison, Recombination, Recombinación, Ruthénium, Ruthenium, Rutenio, Réduction chimique, Chemical reduction, Reducción química, Substrat, Substrate, Substrato, Traitement surface, Surface treatment, Tratamiento superficie, Transport, Transporte, Al2O3, O Ti, and TiO2

Atomic layer deposition (ALD) was used to fabricate Al2O3 recombination barriers in solid-state dye-sensitized solar cells (ss-DSSCs) employing an organic hole transport material (HTM) for the first time. Al2O3 recombination barriers of varying thickness were incorporated into efficient ss-DSSCs utilizing the Z907 dye adsorbed onto a 2 μm-thick nanoporous TiO2 active layer and the HTM spiro-OMeTAD. The impact of Al2O3 barriers was also studied in devices employing different dyes, with increased active layer thicknesses, and with substrates that did not undergo the TiCl4 surface treatment. In all instances, electron lifetimes (as determined by transient photovoltage measurements) increased and dark current was suppressed after Al2O3 deposition. However, only when the TiCl4 treatment was eliminated did device efficiency increase; in all other instances efficiency decreased due to a drop in short-circuit current. These results are attributed in the former case to the similar effects of Al2O3 ALD and the TiCl4 surface treatment whereas the insulating properties of Al2O3 hinder charge injection and lead to current loss in TiCl4-treated devices. The impact of Al2O3 barrier layers was unaffected by doubling the active layer thickness or using an alternative ruthenium dye, but a metal-free donor-π-acceptor dye exhibited a much smaller decrease in current due to its higher excited state energy. We develop a model employing prior research on Al2O3 growth and dye kinetics that successfully predicts the reduction in device current as a function of ALD cycles and is extendable to different dye―barrier systems.

Organic chemistry, Chimie organique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Divers (électroosmose, électrophorèse, électrochromisme, électrocristallisation, ...), Miscellaneous (electroosmosis, electrophoresis, electrochromism, electrocrystallization, ...), Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Chimie minerale et origine de la vie, Inorganic chemistry and origins of life, Préparations et propriétés, Preparations and properties, Sels complexes, Coordination compounds, Alcool, Alcohol, Alkylamine, Alquilamina, Butanol, Chaîne courte, Short chain, Cadena corta, Circuit imprimé, Printed circuit, Circuito imprimido, Complexation, Complexación, Composé hydrophile, Hydrophilic compound, Compuesto hidrofilo, Composé hydrophobe, Hydrophobic compound, Compuesto hidrofobo, Composé non soluble, Insoluble compound, Compuesto no soluble, Couche mince, Thin film, Capa fina, Dépôt centrifugation, Spin-on coating, Eau, Water, Agua, Electrochromisme, Electrochromism, Electrocromismo, Fer III Hexacyanoferrate, Iron III Hexacyanoferrates, Hierro III Hexacianoferrato, Hydrophobicité, Hydrophobicity, Hidrofobicidad, Liaison chimique, Chemical bond, Enlace químico, Nanoparticule, Nanoparticle, Nanopartícula, Réaction homogène, Homogeneous reaction, Reacción homogénea, Solvant organique, Organic solvent, Solvente orgánico, Synthèse chimique, Chemical synthesis, Síntesis química, Traitement surface, Surface treatment, Tratamiento superficie, and Propylamine

An insoluble solid of historic Prussian blue (PB) was transformed into dispersible PB nanoparticles in water and various hydrophilic and hydrophobic organic solvents. Via hybrid surface modification using Na4[FeII(CN)6] and short-chain alkylamines, the insoluble PB was successfully dispersed in hydrophilic-and-hydrophobic boundary alcohols, such as n-butanol. The n-butanol-dispersible PB nanoparticles afforded homogeneous spin-coated thin films on various substrates. The chemisorbed shorter-chain alkylamines, n-propylamines, of the PB nanoparticles were thermally released at 100 °C from their surfaces to present stubborn electrochromic PB thin films adhering to the substrate via mutual coordination-bonding networks.

Organic chemistry, Chimie organique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Sciences appliquees, Applied sciences, Energie, Energy, Energie naturelle, Natural energy, Biomasse, Biomass, Biomasse, Biomass, Biomasa, Chimie verte, Green chemistry, Química verde, Décomposition, Decomposition, Descomposición, Haute température, High temperature, Alta temperatura, Herbe, Grass, Nanoparticule, Nanoparticle, Nanopartícula, Partie molle, Soft tissue, Parte blanda, Photoluminescence, Fotoluminiscencia, Pyrolyse, Pyrolysis, Pirólisis, Stabilité, Stability, Estabilidad, Synthèse chimique, Chemical synthesis, Síntesis química, Sélectivité, Selectivity, Selectividad, Traitement surface, Surface treatment, and Tratamiento superficie

We present an environmentally benign, energy efficient and readily scalable approach to synthesize photoluminescent carbogenic nanoparticles directly from soft tissue biomass. Our approach relies on the pyrolytic decomposition of grass that gives rise to the formation of well-defined nanoparticles. The carbogenic nanoparticles can be readily surface modified, generating a series of highly selective photoluminescent materials that exhibit remarkable stability upon prolonged exposure to aggressive, high-temperature, high-salinity environment.

Organic chemistry, Chimie organique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Théorie des réactions, cinétique générale. Catalyse. Nomenclature, documentation chimique, informatique chimique, Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry, Catalyse, Catalysis, Catalyseurs: préparations et propriétés, Catalysts: preparations and properties, Etat colloïdal et états dispersés, Colloidal state and disperse state, Matériaux poreux, Porous materials, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Métal transition, Transition metal, Metal transición, Acide glutarique, Glutaric acid, Glutárico ácido, Acide organique, Organic acids, Acido orgánico, Aminolyse, Aminolysis, Aminolisis, Biodégradabilité, Biodegradability, Biodegradabilidad, Biomatériau, Biomaterial, Catalyseur, Catalyst, Catalizador, Chimie verte, Green chemistry, Química verde, Chlorure de sodium, Sodium chloride, Sodio cloruro, Composé biomimétique, Biomimetic compound, Compuesto biomimético, Composé hydrophobe, Hydrophobic compound, Compuesto hidrofobo, Dimension particule, Particle size, Dimensión partícula, Dimension pore, Pore size, Dimensión poro, Dioxyde de carbone, Carbon dioxide, Carbono dióxido, Dépressurisation, Depressurization, Depresionación, Echelle grande, Large scale, Escala grande, Etat supercritique, Supercritical state, Estado supercrítico, Fibroblaste, Fibroblast, Fibroblasto, Gonflant, Blowing agent, Hinchador, Gélatine, Gelatin, Gelatina, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Hydrophobicité, Hydrophobicity, Hidrofobicidad, Lixiviation, Lixiviación, Matériau poreux, Porous material, Material poroso, Microscopie fluorescence, Fluorescence microscopy, Microscopía fluorescencia, Monomère, Monomer, Monómero, Moussage, Foaming, Espumación, Pore, Poro, Porosité, Porosity, Porosidad, Procédé expansion, Foaming process, Procedimiento expansión, Protéine, Protein, Proteína, Réaction one pot, One pot reaction, Reacción one pot, Solvant organique, Organic solvent, Solvente orgánico, Structure 3 dimensions, Three dimensional structure, Estructura 3 dimensiones, Synthèse chimique, Chemical synthesis, Síntesis química, Toxicité, Toxicity, Toxicidad, Traitement surface, Surface treatment, Tratamiento superficie, Vitesse réaction, Reaction rate, Velocidad reacción, Zinc, Polymère biodégradable, and Propène carbonate polymère

The aim of this study was to develop an environmentally friendly process for the fabrication of three dimensional (3D) biomimetic scaffolds from biodegradable poly(propylene carbonate) (PPC). Prior to production of scaffolds, PPC was synthesized using a one-pot process in which the zinc glutarate catalyst was first fabricated in a supercritical CO2 system. The scaffolds were then prepared by gas foaming/salt leaching followed by aminolysis and layer-by-layer (LBL) gelatin assembly on the surface. The pore size and interconnectivity were controlled by the variation of gas foaming process parameters such as temperature, CO2 pressure, depressurization rate and particle size of salt (NaCl). The pore size was within the range of 116 ± 53 to 418 ± 84 μm and the porosity was between 69.8 and 92.3%. The results of micro-CT scan analysis demonstrated that porosity and pore interconnectivity were enhanced by increasing the pore size. However, the compressive modulus of hydrated scaffolds was decreased from 380 ± 90 to 200 ± 50 kPa, when the pore size was increased from 232 ± 91 to 411 ± 108 μm. The results of fluorescence microscopy demonstrated that gelatin was uniformly deposited on the 3D scaffolds. Surface modification of hydrophobic PPC scaffolds substantially increased the fibroblast cells attachment, penetration, and proliferation. The results of this study demonstrated the feasibility of eliminating toxic organic solvents in the synthesis of a solid based catalyst and processing PPC polymer into tissue scaffolds. The clean technology developed will be of great value for large scale production of biodegradable PPC that can be used for many purposes such as packaging products and plastic bags. In addition, it was shown that PPC can be considered as an alternative biomaterial for tissue engineering applications.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Atomic molecular physics, Physique atomique et moléculaire, 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, Etat colloïdal et états dispersés, Colloidal state and disperse state, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Acétate, Acetate, Acetato, Adsorption, Adsorción, Blocage, Blocking, Bloqueo, Coefficient diffusion, Diffusion coefficient, Coeficiente difusión, Colorant, Dyes, Colorante, Composé de métal de transition, Transition element compounds, Conduction, Conducción, Constante vitesse, Rate constant, Constante velocidad, Conversion, Conversión, Densité charge, Charge density, Densidad carga, Efficacité, Efficiency, Eficacia, Electrode, Electrodes, Electrodo, Electron, Electrons, Electrón, Frittage, Sintering, Sinterización, Ion, Ions, Ión, Matériau poreux, Porous material, Material poroso, Modification, Modificación, Nanoporosité, Nanoporosity, Nanoporosidad, Oxyde de titane, Titanium oxide, Titanio óxido, Recombinaison, Recombination, Recombinación, Strontium, Estroncio, Séparation charge, Charge separation, Separación carga, Traitement surface, Surface treatment, Tratamiento superficie, O Ti, and TiO2

Surface modification plays a crucial role in improving the efficiency of dye-sensitized solar cells (DSSCs), but the reported surface treatments are in general superior to the untreated TiO2 but inferior to the typical TiCl4-treated TiO2 in terms of solar cell performance. This work demonstrates a two-step treatment of the nanoporous titania surface with strontium acetate [Sr(OAc)2] and TiCl4 in order, each step followed by sintering. An electronically insulating layer of SrCO3 is formed on the TiO2 surface via the Sr(OAc)2 treatment and then a fresh TiO2 layer is deposited on top of the SrCO3 layer via the TiCl4 treatment, corresponding to a double layer of Sr(OAc)2/TiO2 coated on the TiO2 surface. As compared to the typical TiCl4-treated DSSC, the Sr(OAc)2―TiCl4 treated DSSC improves short-circuit photocurrent (Jsc) by 17%, open-circuit photovoltage (Voc) by 2%, and power conversion efficiency by 20%. These results indicate that the Sr(OAc)2―TiCl4 treatment is better than the often used TiCl4 treatment for fabrication of efficient DSSCs. Charge density at open circuit and controlled intensity modulated photocurrent/ photovoltage spectroscopy reveal that the two electrodes show almost same conduction band level but different electron diffusion coefficient and charge recombination rate constant. Owing to the blocking effect of the SrCO3 layer on electron recombination with I3― ions, the charge recombination rate constant of the Sr(OAc)2―TiCl4 treated DSSC is half that of the TiCl4-treated DSSC, accounting well for the difference of their Voc. The improved Jsc is also attributed to the middle SrCO3 layer, which increases dye adsorption and may improve charge separation efficiency due to the blocking effect of SrCO3 on charge recombination.

Organic chemistry, Chimie organique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Emulsions. Microémulsions. Mousses, Emulsions. Microemulsions. Foams, Matière plastique, Plastics, Material plástico, Argile, Clay, Arcilla, Barrière énergie, Energy barrier, Barrera energía, Chimie verte, Green chemistry, Química verde, Dispersion, Dispersión, Délaminage, Delamination, Delaminación, Eau, Water, Agua, Electron, Electrons, Electrón, Gonflement, Swelling, Inflamiento, Isocyanate organique, Organic isocyanate, Isocianato orgánico, Moussage, Foaming, Espumación, Mousse (émulsion), Foam, Espuma, Nanocomposite, Nanocompuesto, Oligomère, Oligomer, Oligómero, Particule, Particle, Partícula, Phase gazeuse, Gas phase, Fase gaseosa, Plastique alvéolaire, Cellular plastic, Plástico espumoso, Polymère, Polymer, Polímero, Solution aqueuse, Aqueous solution, Solución acuosa, Solvant organique, Organic solvent, Solvente orgánico, Synthèse chimique, Chemical synthesis, Síntesis química, Traitement surface, Surface treatment, Tratamiento superficie, Transfert masse, Mass transfer, Transferencia masa, Hectorite, and Silicate lamellaire

The property of osmotic swelling of a hectorite clay suspension in water is exploited for dispersing it in a polymeric foam matrix. This green route eludes the surface modification of clay as well as the mediation by organic solvents for clay dispersion during foaming. The route follows the initial swelling and partial delamination of clay galleries by water molecules, followed by further dispersion in an oligomeric isocyanate foaming component, before conducting reactive foaming. A nominal mass fraction of clay provides an effective barrier, restricting the gas phase mass transport in the foam. Electron microscopic investigations show that clay particles are preferentially located on the lamellar part of the microscopic foam cell, rather than on plateau borders.

Organic chemistry, Chimie organique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Théorie des réactions, cinétique générale. Catalyse. Nomenclature, documentation chimique, informatique chimique, Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry, Catalyse, Catalysis, Catalyseurs: préparations et propriétés, Catalysts: preparations and properties, Physicochimie des réactions induites par rayonnements, particules et ultrasons, Physical chemistry of induced reactions (with radiations, particles and ultrasonics), Photochimie, Photochemistry, Chimie organique, Organic chemistry, Réactivité et mécanismes, Reactivity and mechanisms, Cinétique et mécanisme des réactions, Kinetics and mechanisms, Préparations et propriétés, Preparations and properties, Composés benzéniques non condensés, Noncondensed benzenic compounds, Agrégat métallique, Metal cluster, Agregado metálico, Alcool benzylique, Benzyl alcohol, Alcohol bencílico, Benzaldéhyde, Benzaldehyde, Benzaldehído, Caractérisation, Characterization, Caracterización, Catalyseur, Catalyst, Catalizador, Chimie verte, Green chemistry, Química verde, Cinétique, Kinetics, Cinética, Composé benzénique, Benzenic compound, Compuesto bencénico, Composé de métal de transition, Transition element compounds, Dérivé du benzaldéhyde, Benzaldehyde derivatives, Benzaldehído derivado, Iridium, Iridio, Molécule d'oxygène, Oxygen molecules, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Métal transition, Transition metal, Metal transición, Oxydation, Oxidation, Oxidación, Oxyde de titane, Titanium oxide, Titanio óxido, Photocatalyse, Photocatalysis, Fotocatálisis, Platinoïde, Platinoid, Platinoide, Préparation, Preparation, Preparación, Réaction catalytique, Catalytic reaction, Reacción catalítica, Réaction hétérogène, Heterogeneous reaction, Reacción heterogénea, Réaction sans solvant, Solvent free reaction, Reacción sin solvente, Synthèse chimique, Chemical synthesis, Síntesis química, Synthèse organique, Organic synthesis, Síntesis orgánica, Sélectivité, Selectivity, Selectividad, Titane IV Oxyde, Titanium IV Oxides, Titanio IV Óxido, Traitement surface, Surface treatment, Tratamiento superficie, Vitesse réaction, Reaction rate, Velocidad reacción, O Ti, and TiO2

Heterogeneous photocatalysis offers a promising route to realize green oxidation processes in organic synthesis. In this research, the solvent-free selective photocatalytic oxidation of benzyl alcohol to benzaldehyde in the presence molecular oxygen was studied by using TiO2 and modified TiO2 as photocatalysts. The surface modification of TiO2 by transition metal clusters dramatically enhanced the photocatalytic oxidation activity. Ir/TiO2 prepared by photodeposition showed a remarkably high activity for the photocatalytic oxidation of benzyl alcohol, and an average reaction rate of 14538 umol h―1 gcat―1 could be obtained. The effect of preparation method, iridium loading and reaction conditions on the catalytic performance of Ir/TiO2 is investigated in detail. Based on the catalytic and characterization results, the problem of product selectivity and the reaction mechanism of the photocatalytic oxidation of benzyl alcohol over Ir/TiO2 are discussed.

Analytical chemistry, Chimie analytique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie analytique, Analytical chemistry, Divers, Miscellaneous, Sciences appliquees, Applied sciences, Pollution, Pollution globale de l'environnement, Global environmental pollution, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biologie moleculaire et cellulaire, Molecular and cellular biology, Méthodes diverses, Diverse techniques, Mécanique fluide, Fluid mechanics, Mecánica flúido, Application, Aplicación, Article synthèse, Review, Artículo síntesis, Conception, Design, Diseño, DNA, Dispositif, Device, Dispositivo, Détection, Detection, Detección, Environnement, Environment, Medio ambiente, Etude comparative, Comparative study, Estudio comparativo, Microfluidique, Microfluidics, Microfluidic, Monitorage, Monitoring, Monitoreo, Méthode immunologique, Immunological method, Método inmunológico, Protéine, Protein, Proteína, Protéomique, Proteomics, Proteómica, Silicium, Silicon, Silicio, Stratégie, Strategy, Estrategia, Synthèse chimique, Chemical synthesis, Síntesis química, Traitement surface, Surface treatment, Tratamiento superficie, Utilisation, Use, Uso, Verre, Glass, and Vidrio

Microfluidics is a platform technology that has been used for genomics, proteomics, chemical synthesis, environment monitoring, cellular studies, and other applications. The fabrication materials of microfluidic devices have traditionally included silicon and glass, but plastics have gained increasing attention in the past few years. We focus this review on thermoplastic microfluidic devices and their applications in protein and DNA analysis. We outline the device design and fabrication methods, followed by discussion on the strategies of surface treatment. We then concentrate on several significant advancements in applying thermoplastic microfluidic devices to protein separation, immunoassays, and DNA analysis. Comparison among numerous efforts, as well as the discussion on the challenges and innovation associated with detection, is presented.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Atomic molecular physics, Physique atomique et moléculaire, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie des réactions induites par rayonnements, particules et ultrasons, Physical chemistry of induced reactions (with radiations, particles and ultrasonics), Photochimie, Photochemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Composé binaire, Binary compound, Compuesto binario, Absorption optique, Optical absorption, Absorción óptica, Anatase, Anatasa, Calcul, Calculation, Cálculo, Composé de métal de transition, Transition element compounds, Conversion, Conversión, Distorsion réseau, Lattice distortion, Distorsión red, Efficacité, Efficiency, Eficacia, Electron, Electrons, Electrón, Energie, Energy, Energía, Hydrogène, Hydrogen, Hidrógeno, Hydrogénation, Hydrogenation, Hidrogenación, Liaison disponible, Dangling bond, Enlace disponible, Mécanisme, Mechanism, Mecanismo, Nanocristal, Nanocrystal, Nanoparticule, Nanoparticle, Nanopartícula, Oxyde de titane, Titanium oxide, Titanio óxido, Photocatalyse, Photocatalysis, Fotocatálisis, Séparation, Separation, Separación, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement surface, Surface treatment, Tratamiento superficie, Valence, Valencia, O Ti, and TiO2

Disorder-engineered nanophase anatase TiO2 through hydrogenation has been demonstrated to exhibit substantial solar-driven photocatalytic activities [X. Chen, L. Liu, P. Y. Yu, S. S. Mao, Science, 2011, 331, 746], while the detailed image of the disorder is unclear, and the role of the hydrogenation as well as the mechanism of high photoactivity is still ambiguous. Based on first-principles calculations, we find by taking into account the synergic effect of Ti―H and O―H bonds that hydrogen atoms can be chemically absorbed both on Ti5c and O2c atoms for (101), (001), and (100) surfaces, while previous studies predicted that chemical absorption of H on both Ti5c and O2c only takes place on the (001) surface due to overlooking the synergic effect. The hydrogenation induces obvious lattice distortions on (101) and (100) surfaces of nanoparticles enhancing the intraband coupling within the valence band, while the (001) surface is not largely affected. Different from the previous understanding that the lattice disorder accounts for the induced mid-gap states while the hydrogen only stabilizes the lattice disorders by passivating their dangling bonds, we find that the adatoms not only induce the lattice disorders but also interact strongly with the Ti 3d and O 2p states, resulting in a considerable contribution to the mid-gap states. The optical absorption is dramatically red shifted due to the mid-gap states and the photogenerated electron―hole separation is substantially promoted as a result of electron―hole flow between different facets of hydrogenated nanoparticles, which may account for the exceptional high energy conversion efficiency under solar irradiation. Even more interestingly, we find that hydrogenation reverses the redox behavior of different surfaces of nanoparticles, which provides new hints that one can tune the photoexcited electron―hole flow between different surfaces of nanoparticles in accordance to one's request by appropriate chemical surface treatment. We believe that band-offset-engineering between different facets of nanocrystals can be an effective way to facilitate energy conversion efficiency and should be applicable to other nanophase materials.

Organic chemistry, Chimie organique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Chimie organique, Organic chemistry, Préparations et propriétés, Preparations and properties, Composés organométalloïdiques et organométalliques, Organometalloidal and organometallic compounds, Dérivés de si, Si derivatives, Dioxyde de carbone, Carbon dioxide, Carbono dióxido, Etat supercritique, Supercritical state, Estado supercrítico, Fonctionnalisation, Functionalization, Funciónalización, Liquide ionique, Ionic liquid, Líquido iónico, Nanoparticule, Nanoparticle, Nanopartícula, Oxyde de silicium, Silicon oxides, Phosphonium, Fosfonio, Silane organique, Organic silane, Silano orgánico, Silice, Silica, Sílice, Traitement surface, Surface treatment, Tratamiento superficie, SiO2, and Silanol

A phosphonium ionic liquid is used as an activator of silanol groups to improve the surface functionalization of silica nanoparticles with fluorosilanes in supercritical CO2.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Atomic molecular physics, Physique atomique et moléculaire, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, 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, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biophysique moleculaire, Molecular biophysics, Chimie physique en biologie, Physical chemistry in biology, Composé benzénique condensé, Condensed benzenic compound, Compuesto bencénico condensado, Composé tricyclique, Tricyclic compound, Compuesto tricíclico, Hydrocarbure, Hydrocarbon, Hidrocarburo, Anthracène, Anthracene, Antraceno, Anthraquinone, Antraquinona, Biodétecteur, Biosensor, Biodetector, Bioélectrochimie, Bioelectrochemistry, Bioelectroquímica, Caractérisation, Characterization, Caracterización, Carbone, Carbon, Carbono, Compte rendu, Report, Informe, Construction, Construcción, Contact électrique, Electric contact, Contacto eléctrico, Couche monomoléculaire, Monolayer, Capa monomolecular, Diamine, Diamina, Electrode, Electrodes, Electrodo, Enzyme, Enzima, Immobilisation, Immobilization, Inmovilización, Matériau modifié, Modified material, Material modificado, Méthodologie, Methodology, Metodología, Phase solide, Solid phase, Fase sólida, Pile combustible biochimique, Biochemical fuel cell, Pila combustible bioquímica, Préparation, Preparation, Preparación, Rayon X, X ray, Rayos X, Site actif, Active site, Lugar activo, Spectrométrie photoélectron, Photoelectron spectrometry, Espectrometría fotoelectrón, Support, Soporte, Technique, Técnica, Traitement surface, Surface treatment, Tratamiento superficie, Tête, Head, Cabeza, Utilisation, Use, and Uso

Surface modification techniques are essential to the construction of enzyme based elements of biofuel cells and biosensors. In this article we report on the preparation and characterisation of modified carbon electrodes which were used as supports for the immobilisation of laccase from Trametes hirsuta. The electrodes were electrochemically modified with diamine or diazonium linkers followed by attachment of either anthracene or anthraquinone head groups using solid phase chemical methodology. These well defined surfaces were found to effectively bind laccase and to provide direct electrical contact to the enzyme active site, as evidenced by XPS, EIS and voltammetry, respectively. The influence of the type of linker and head group on enzyme binding and bioelectrocatalytic activity are evaluated.

Chemistry, Chimie, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Divers, Other topics in nanoscale materials and structures, Agent contraste résonance magnétique, Magnetic resonance contrast agent, Agente contraste resonancia magnética, Biocompatibilité, Biocompatibility, Biocompatibilidad, Fonctionnalisation, Functionalization, Funciónalización, In vivo, Modification chimique, Chemical modification, Modificación química, Nanomatériau, Nanostructured materials, Nanoparticule, Nanoparticles, Oxyde de fer, Iron oxide, Hierro óxido, Superparamagnétisme, Superparamagnetism, Traitement surface, and Surface treatments

Superparamagnetic iron oxide nanoparticles have received great attention due to their applications as contrast agents for magnetic resonance imaging (MRI). This feature article briefly introduces the concepts of MRI and MRI contrast agents, and then mainly discusses the synthesis, surface modification, surface functionalization, colloidal stability and biocompatibility of iron oxide particles, followed by their MRI applications.

Chemistry, Chimie, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Matériaux nanocristallins, Nanocrystalline materials, 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, Méthodes et appareillages divers, Various methods and equipments, Autres, Others, Application médicale, Medical application, Aplicación medical, Article synthèse, Reviews, Composition surface, Surface composition, Contraste image, Image contrast, Imagen contraste, Formation image, Imaging, Imagerie RMN, NMR imaging, Modification chimique, Chemical modification, Modificación química, Molécule organique, Organic molecule, Molécula orgánica, Nanomatériau magnétique, Magnetic nanomaterial, Nanomaterial magnético, Nanoparticule, Nanoparticles, Particule magnétique, Magnetic particles, Propriété magnétique, Magnetic properties, Revêtement chimique, Chemical coating, Stabilité chimique, Chemical stability, Estabilidad química, Structure surface, Surface structure, Synthèse chimique, Chemical synthesis, Síntesis química, Traitement surface, Surface treatments, and 8107B

Magnetic nanoparticles (MNPs) have attracted enormous research attention due to their unique magnetic properties that enable the detection by non-invasive medical imaging modality―magnetic resonance imaging (MRI). By incorporating advanced features, such as specific targeting, multimodality and therapeutic delivery, the detectability and applicability of MNPs have been dramatically expanded. A delicate design of structure, composition and surface chemistry is essential to achieving the desired properties in MNP systems, such as high imaging-contrast and chemical stability, non-fouling surface, target specificity and/or multimodality. This article presents the design fundamentals on the development of MNP systems, from discussion of material selection for nanoparticle cores and coatings, strategies for chemical synthesis and surface modification and their merits and limitations, to conjugation of special biomolecules for intended functions, and reviews the recent advances in the field.

Chemistry, Chimie, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Fils quantiques, Quantum wires, Divers, Other topics in nanoscale materials and structures, Méthodes de nanofabrication, Methods of nanofabrication, Autoassemblage, Self-assembly, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés d'ionisation, Ionization properties, Analyse quantitative, Quantitative chemical analysis, Autoassemblage, Self-assembly, Chondroïtine sulfate, Chondroitin sulfate, Condroitina sulfato, Collagène, Collagen, Couche multimoléculaire, Multilayer, Capa multimolecular, Cytotoxicité, Cytotoxicity, Citotoxicidad, Césium, Cesium, Désorption, Desorption, Héparine, Heparin, Matériau composite, Composite materials, Microscopie confocale, Confocal microscopy, Microscopía confocal, Modification chimique, Chemical modification, Modificación química, Multicouche, Multilayers, Nanobâtonnet, Nanorod, Nanopalito, Nanomatériau, Nanostructured materials, Nanoparticule, Nanoparticles, Or, Gold, Polyanion, Polianión, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Traitement surface, Surface treatments, Turbidité, Turbidity, 8107V, 8116D, and 8235R

The sulfated glycosaminoglycans (sGAG) heparin and chondroitin sulfate (CS) were immobilized on the surfaces of gold nanorods as part of a polyelectrolyte multilayer. The effects of these nanomaterials on the self-assembly of type I collagen were examined by turbidity assays and microscopy, and desorption of sGAG from nanomaterial-collagen composites was quantified biochemically. The interactions of sGAG-coated nanorods with cardiac cells were also explored through a collagen gel contraction assay and confocal microscopy. In contrast to soluble forms of sGAG, sGAG-coated nanorods consistently accelerated collagen fibrillogenesis. Soluble heparin, and heparin- and CS-coated nanorods inhibited cell-mediated contraction of collagen gels, whereas soluble CS did not. Both heparin and CS-coated nanorods were detected in the peri- and/or intra-cellular compartments of the cells, but there was no evidence of cytotoxicity over 72 h of culture. These results indicate that biological polyanions, such as sGAG, may be useful in the modification of nanoparticle surface chemistry for biological and/or therapeutic applications.