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SHEEP, CHICKENS, MOLECULAR weights, WOOL, and FEATHERS

Chicken feathers and sheep wool are at present considered two major agro-industrial residues which are hard to be disposed. Therefore finding applications for these residues is interesting from the viewpoint of Circular Economy. The knowledge of the properties and characteristics of keratins, which are the main constituent of these materials, can help designing final applications for them. This report presents the results of the comparative analysis of the molecular weights of keratins from Lachas heep (Ovis aries) and consumer chicken (Gallus domesticus) obtained by reductive extraction with sodium tioglycolate inalkalyne media. The analysis was carried out trough polyacrylamide gel electrophoresis and showed that wool keratin has molecular weightfractions of 56, 47, 14, 10 y 8 KDa, higher on average than those of the feathers, only with lower molecular weight fractions, in the range of 8-6 KDa. [ABSTRACT FROM AUTHOR]

Mechanical engineering, Génie mécanique, Mechanics acoustics, Mécanique et acoustique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Generalites, General, Instruments, appareillage, composants et techniques communs à plusieurs branches de la physique et de l'astronomie, Instruments, apparatus, components and techniques common to several branches of physics and astronomy, Techniques et équipements généraux, General equipment and techniques, Systèmes asservis et systèmes de commande; robots, Servo and control equipment; robots, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des solides, Solid mechanics, Mécanique des structures et des milieux continus, Structural and continuum mechanics, Méthodes de mesure et d'essai, Measurement and testing methods, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Propriétés et essais, Properties and testing, Essais et contrôles, Testing and control, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Agent surface anionique, Anionic surfactant, Agente superficie aniónico, Agent surface cationique, Cationic surfactant, Agente superficie catiónico, Autoassemblage, Self assembly, Autoensamble, Calorimétrie différentielle balayage, Differential scanning calorimetry, Análisis calorimétrico barrido exploración, Charge dynamique, Dynamic load, Carga dinámica, Charge thermique, Thermal load, Carga térmica, Durcissement (matière plastique), Curing (plastics), Endurecimiento (material plástico), Entaille, Notch, Entalla, Epoxyde résine, Epoxy resin, Epóxido resina, Etat solide, Solid state, Estado sólido, In situ, Masse moléculaire, Molecular mass, Masa molecular, Mesure, Measurement, Medida, Polymère réticulé, Crosslinked polymer, Polímero reticulado, Propriété dynamomécanique, Dynamic mechanical properties, Propiedad dinamomecánica, Propriété thermomécanique, Thermomechanical properties, Propriedad termomecánica, Rayonnement IR proche, Near infrared radiation, Radiación infrarroja cercana, Restauration (propriété), Recovery (properties), Restauración (propiedad), Réparation, Repair, Reparación, Spectrométrie IR, Infrared spectrometry, Espectrometría IR, Thermoplasticité, Thermoplasticity, Termoplasticidad, Thermoplastique, Thermoplastics, Termoplástica, Viscoélasticité, Viscoelasticity, Viscoelasticidad, Polymer networks, self-healing, and thermoplastic healing

Solid-state healing of epoxy networks is shown to be an effective and robust mechanism for highly cross-linked epoxy networks. Using diglycidyl ether of bisphenol A epoxy resin and diethyltoluenediamine, the cured epoxy network is transformed into a mendable system using phenoxy resin and low-molecular-weight polybisphenol A-co-epichlorohydrin) thermoplastic modifiers. Using functionally terminated low-molecular-weight poly(bisphenol A-co-epichlorohydrina) thermoplastic modifiers as healing agents reveals that salicylic acid or neutralized sodium salicylate groups produce healing similar to high-molecular-weight non-functional phenoxy resin as measured using single-end notched beam testing. The miscibility of both thermoplastics in the diglycidyl ether of bisphenol A/diethyltoluenediamine system was evaluated using differential scanning calorimetry and dynamic mechanical thermal analysis and identified as being important to promoting healing. Near-infrared spectroscopy showed that the network structure was unaffected by the thermoplastic modification, suggesting that healing occurred primarily through physical or non-covalent mechanisms rather than covalent bonding. The potential for self-assembly of the salicylic acid and neutralized sodium salicylate groups to form a high-molecular-weight thermoplastic in situ was also discussed as being a possible reason for the improved level of healing with the low-molecular-weight thermoplastic.

Food science technology, Sciences technologies alimentaires, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Industries agroalimentaires, Food industries, Polyoside, Polysaccharide, Poliósido, Arabinoxylane, Arabinoxylan, Arabinoxilano, Article synthèse, Review, Artículo síntesis, Céréale sous produit, Cereal by product, Cereal subproducto, Extraction, Extracción, Masse moléculaire, Molecular mass, Masa molecular, Modification, Modificación, Rendement, Yield, Rendimiento, Technologie, Technology, Tecnología, Ara/Xly, Arabinoxylans, Molecular weight, and Yields

Arabinoxylans (AXs) are one of the most important groups of hemicelluloses in the endosperm and outer layers of cereal grains. However, the macromolecular characteristics of extracted AXs and the extraction yields achieved exhibit huge differences. These differences are apparently dependent on the different extraction and modification methods used. This paper aims to review the extraction and modification methods used in the separation of AXs from cereal by-products as reported in previous studies. The effects of different extraction and modification methods on AX extraction yields, molecular characteristics and properties were evaluated. The influence of various extraction methods including chemical solvent extraction, enzymatic extraction and modification, and mechanically-assisted extraction on molecular structure (the ratio of arabinose to xylose and molecular weight distribution) of AXs are compared and discussed in this paper.

Chemical engineering, Génie chimique, Computer science, Informatique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Equations d'état, équilibres de phases et transformations de phases, Equations of state, phase equilibria, and phase transitions, Transformations de phases particulières, Specific phase transitions, Transformations solide-solide, Solid-solid transitions, Sciences appliquees, Applied sciences, Genie chimique, Chemical engineering, Réacteurs, Reactors, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymérisation, Polymerization, Copolymérisation, Copolymerization, Condition opératoire, Operating conditions, Condición operatoria, Copolymérisation émulsion, Emulsion copolymerization, Copolimerización emulsión, Devis descriptif, Product specification, Presupuesto descriptivo, Dispositif alimentation, Feeding device, Dispositivo alimentación, Distribution dimension particule, Particle size distribution, Distribución dimensión partícula, Emulsion, Emulsión, En semi continu, Semicontinuous, En semicontinuo, Etude expérimentale, Experimental study, Estudio experimental, Masse moléculaire, Molecular mass, Masa molecular, Modélisation, Modeling, Modelización, Monomère, Monomer, Monómero, Optimisation, Optimization, Optimización, Paramétrisation, Parameterization, Parametrización, Poids, Weight, Peso, Polymère, Polymer, Polímero, Polymérisation émulsion, Emulsion polymerization, Polimerización emulsión, Procédé discontinu, Batch process, Procedimiento discontínuo, Productivité, Productivity, Productividad, Programmation dynamique, Dynamic programming, Programación dinámica, Réacteur chimique, Chemical reactor, Reactor químico, Réacteur polymérisation, Polymerization reactor, Reactor polimerización, Structure coeur couche, Core shell structure, Estructura núcleo cascarón, Styrène, Styrene, Estireno, Température transition, Transition temperature, Temperatura transición, Transition vitreuse, Glass transition, Transición vítrea, Vitesse avancement, Penetration rate, Velocidad penetración, Chain transfer agent, Control vector parameterization, Dynamic optimization, and Fedbatch process

In this paper dynamic optimization of a lab-scale semi-batch emulsion copolymerization reactor for styrene and butyl acrylate in the presence of a chain transfer agent (CTA) is studied. The mathematical model of the process, previously developed and experimentally validated, is used to predict the glass transition temperature of produced polymer, the number and weight average molecular weights, the monomers global conversion, the particle size distribution, and the amount of residual monomers. The model is implemented within gPROMS environment for modeling and optimization. It is desired to compute feed rate profiles of pre-emulsioned monomers, inhibitor and CTA that will allow the production of polymer particles with prescribed core-shell morphology with high productivity. The results obtained for different operating conditions and various additional product specifications are presented. The resulting feeding profiles are analyzed from the perspective of the nature of emulsion polymerization process and some interesting conclusions are drawn.

Energy, Énergie, Geology, Géologie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Combustibles, Fuels, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Analyse quantitative, Quantitative analysis, Análisis cuantitativo, Centre paramagnétique, Paramagnetic center, Centro paramagnético, Charbon pulvérisé, Pulverized coal, Carbón pulverizado, Dimension particule, Particle size, Dimensión partícula, Déminéralisation, Demineralization, Desmineralización, Etude comparative, Comparative study, Estudio comparativo, Masse moléculaire, Molecular mass, Masa molecular, Oxydation, Oxidation, Oxidación, Propriété chimique, Chemical properties, Propiedad química, Pyrite, Pirita, Radical libre, Free radical, Résonance paramagnétique électronique, Electron paramagnetic resonance, Resonancia paramagnética electrónica, Power saturation behavior, and Superfine pulverized coal particle

Inorganic matter in coal significantly influences its chemical properties and potential utilizations. Electron paramagnetic resonance (EPR) characteristics can be affected by inorganic species, and various groups of paramagnetic centers behave differently after demineralization procedures. In this paper, EPR and the power saturation technique were applied to investigate thoroughly the free radical characteristics of acid-treated superfine pulverized coals. Systematic studies were conducted to explore the behaviors of different groups of paramagnetic centers in demineralized and pyrite-free coals. Focus was directed on comparisons of free radical characteristics of coal samples with different particle sizes, indicating that coals with higher maturities and larger particle sizes are much more easily saturated. Compared to raw coals, the acid-treated samples are more susceptible to saturation. Furthermore, the power saturation technique also served as a quantitative analysis method to study the line-broadening mechanism. This technique revealed that the components in coals with higher molecular weights contain more homogeneous components. Worth noticing is that the concentrations of free radicals residues in the acid-treated coals are determined by two competing mechanisms. The oxidation effects would increase the amounts of free radicals while the removal process of certain components in coals has decreasing effects. Multi-component spectra studies reflect that EPR spectra of acid-treated coals are superimposed by one Gaussian and three Lorentzian lines.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Nanotechnologies, nanostructures, nanoobjects, Nanotechnologies, nanostructures, nanoobjets, 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, Etat colloïdal et états dispersés, Colloidal state and disperse state, Emulsions. Microémulsions. Mousses, Emulsions. Microemulsions. Foams, Coalescence, Coalescencia, Déplacement, Displacement, Desplazamiento, Emulsifiant, Emulsifier, Emulsionador, Emulsion huile eau, Oil water emulsion, Emulsión aceite agua, Huile, Oil, Aceite, Masse moléculaire, Molecular mass, Masa molecular, Matière grasse, Fat, Materia grasa, Microviscosité, Microviscosity, Microviscosidad, Mobilité, Mobility, Movilidad, Protéine, Protein, Proteína, Résonance, Resonance, Resonancia, Spin, Electron spin resonance, Globule surface, Low-molecular-weight emulsifiers, O/W-emulsions, Partial coalescence, and Protein displacement

Electron Spin Resonance spectroscopy (ESR) was used to measure the mobility of the spin probe TEMPO in O/W-emulsions. This allowed determination of temperature-dependent microviscosity of the liquid fraction in lipid globules. Six hydrogenated palm kernel oil (HPKO) based emulsions containing caseinate and different combinations of lactic acid ester of monoglyceride (LACTEM), unsaturated monoglycerides (GMU) or saturated monoglyceride (GMS) were studied. The non-solidified oil in emulsions made with LACTEM + GMU had a high microviscosity, whereas the emulsion made with GMS had a low microviscosity. Also the partitioning of TEMPO between the lipid and aqueous phases was found to be highly temperature dependent, most likely due to the change of solid fat content with temperature. This behaviour may mimic the partitioning of aroma compounds in emulsions. The spin probe 5-doxylstearic acid was used to study the mobility of the components at the lipid globule surfaces. At 5 °C all emulsions had a very low surface mobility. At 25 °C the mobility of the spin probe was found to be correlated to the surface protein load. Emulsions with GMU had a high protein surface coverage and low mobility of the spin probe on the droplet surfaces. Conversely, in presence of LACTEM and GMS, the protein surface loads decreased and high surface mobilities were observed. Based on these results it is argued that the high macroscopic viscosity and lipid agglomeration of emulsions containing GMU is due to a lipid globule-protein-network where the lipid globules are connected via caseinate.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Biotechnology, Biotechnologies, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Bactérie lactique, Lactic acid bacteria, Bacteria láctica, Bactérie, Bacteria, Micrococcales, Streptococcaceae, Biosynthèse, Biosynthesis, Biosíntesis, Culture, Cultivo, DNA recombinant, Recombinant DNA, DNA recombinante, En discontinu, Batchwise, En discontinuo, En semi continu, Semicontinuous, En semicontinuo, Expression génique, Gene expression, Expresión genética, Génie métabolique, Metabolic engineering, Ingeniería metabólica, Lactococcus lactis, Masse moléculaire, Molecular mass, Masa molecular, Production, Producción, Batch Processing, Fed-Batch Cultures, and Hyaluronan

Recombinant Lactococcus lactis strains based on the P170 expression system were developed for hyaluronan (HA) production, by incorporating genes from the has operon of Streptococcus zooepidemicus and compared with nisin-inducible recombinant L. lactis strains containing the hasABC and hasABD constructs. It was found across all batch and fed-batch experimental studies that HA concentration and molecular weight (MW) were higher for the P170 expression systems than the corresponding NICE-based strains. The highest hyaluronan MW was obtained for all constructs in batch studies at 60g/L initial glucose concentration, the highest being 2.94 MDa for the P170 strains with hasABC construct (L. lactis APJ3). In fed-batch studies with constant feed rate, the L. lactis APJ3 gave better HA yield (0.03 g/g) than the NICE-based strain. A higher hyaluronan MW was obtained for all strains in pulse fed-batch compared to constant feed experiments, the highest being 2.52 MDa for L. lactis APJ3.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, 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, Matériaux particuliers, Specific materials, Autres matériaux, Other materials, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs optoélectroniques, Optoelectronic devices, Agrégat moléculaire, Molecular cluster, Agregado molecular, Agrégation moléculaire, Molecular aggregation, Agregación molecular, Caractéristique électrique, Electrical characteristic, Característica eléctrica, Diode électroluminescente organique, Organic light emitting diodes, Dispositif optoélectronique, Optoelectronic device, Dispositivo optoelectrónico, Electronique organique, Organic electronics, Electrónica orgánica, Emetteur, Transmitter, Emisor, Evaluation performance, Performance evaluation, Evaluación prestación, Formation film, Film formation, Formación película, Luminance, Luminancia, Masse moléculaire, Molecular mass, Masa molecular, Matériau organique, Organic material, Material orgánico, Molécule petite, Small molecule, Molécula pequeña, Méthode en solution, Growth from solution, Método en solución, Polymère, Polymer, Polímero, Procédé fabrication, Manufacturing process, Procedimiento fabricación, 8105L, 8560J, Organic light emitting diode, Phosphorescent emitter, and Solution processing

Solution processing of low-molecular weight organic materials for optoelectronic devices is a challenging task due to often strong molecular aggregation. We present a facile and universal route for suppressing the aggregation of molecules during wet-deposition of emission layers for organic light emitting diodes by incorporating electronically inactive polymers. Moderate polymer concentrations of about 10 wt.% lead to only minor changes of the electrical performance while at the same time improving the film formation and consequently the device luminance significantly. The device performance matches the performance of vacuum processed devices with the same device architecture.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, 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, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Autoassemblage, Self assembly, Autoensamble, Masse moléculaire, Molecular mass, Masa molecular, Urée, Urea, Urées, Ureas, Bisurea, Organogelation, and Thermoreversible gels

A novel class of toluene based bis urea compounds carrying linear fatty acid units and semicarbazide linkages has been synthesised. The compounds were exhibiting thermoreversible gelation at concentrations below 10 mg/mL in common organic solvents, both aliphatic and aromatic. The effect of the chain length variation of fatty acid units on gelation properties like gelation concentration, gelation time and gel melting temperatures were studied. Choosing a particular gelator of fixed chain length and a specific solvent, the effect of the concentration on the gelation properties were studied. The thermal studies using DSC revealed the presence of phase transitions corresponding to the premelting and melting of the gels during the heating cycle. The morphology of the xerogels studied using SEM revealed a three dimensional network structure while the WAXS studies showed no crystallinity in the xerogels. IR spectra of the gels (solvent subtracted) and solutions in the corresponding solvent showed that a high degree of inter-molecular H bonding exists and absorptions corresponding to NH stretching shifted to lower wave numbers. Thus simple bisurea type of compounds exhibiting gelation ability in a wide range of solvents can be used for making functional gels for various applications.

Cardiology, blood circulation, phlebology, Cardiologie, appareil circulatoire, phlébologie, Hematology, Hématologie, 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, Coagulation sanguine. Cellules sanguines, Blood coagulation. Blood cells, Sciences medicales, Medical sciences, Hemopathies, Hematologic and hematopoietic diseases, Maladies des thrombocytes et coagulopathies, Platelet diseases and coagulopathies, Anticoagulant, Anticoagulante, Coagulation sanguine, Blood coagulation, Coagulación sanguínea, Masse moléculaire, Molecular mass, Masa molecular, Relation structure activité, Structure activity relation, Relación estructura actividad, Sulfate, Sulfates, Sulfato, Fucoïdan, Fucoidan, fucoidan, molecular weight, structure-activity relationship, and sulfates

Fucoidan is a highly complex sulfated polysaccharide commonly extracted from brown seaweed. In addition to their many biological activities, fucoidans have recently been demonstrated to inhibit or increase coagulation at different concentration ranges. Their structural features, i.e. molecular weight (Mw), Mw distribution, degree of sulfation, monosaccharide composition, and different linkages, are known to affect these activities. Therefore, structure-activity relationship (SAR) analysis of fucoidan is crucial for its potential use as a procoagulant. In this study, Fucus vesiculosus (F.v.) fucoidan was fractionated by charge and size as well as over- and desulfated to different degrees to yield preparations with various structural properties. The fractions' pro- and anticoagulant activities were assessed by calibrated automated thrombography (CAT) and activated partial thromboplastin time (aPTT) assays. Binding to and inhibition of the anticoagulant protein tissue factor pathway inhibitor (TFPI) and the ability to activate coagulation via the contact pathway were also investigated. This paper discusses the impact of charge density, size, and sugar composition on fucoidan's pro- and anticoagulant activities. Fucoidan requires a minimal charge density of 0.5 sulfates per sugar unit and a size of 70 sugar units to demonstrate desired procoagulant activities for improvement of haemostasis in factor VIII/factor IX-deficient plasma.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Os, articulations et tissu conjonctif. Antiinflammatoires, Bones, joints and connective tissue. Antiinflammatory agents, Angiospermae, Dicotyledones, Spermatophyta, Activité biologique, Biological activity, Actividad biológica, Antiostéoporotique, Antiosteoporotic, Antiosteoporótico, Cytodifférenciation, Cell differentiation, Diferenciación celular, Etude expérimentale, Experimental study, Estudio experimental, In vitro, Isolement chimique, Chemical isolation, Aislamiento químico, Leguminosae, Masse moléculaire, Molecular mass, Masa molecular, Origine végétale, Plant origin, Origen vegetal, Oside polymère, Oside polymer, Osido polímero, Ostéoblaste, Osteoblast, Osteoblasto, Ostéogenèse, Osteogenesis, Osteogénesis, Plante médicinale, Medicinal plant, Planta medicinal, Racine, Root, Raíz, Structure moléculaire, Molecular structure, Estructura molecular, Astragalus membranaceus, Composition en monosaccharides, Osteoblast differentiation, Osterix, Radix Hedysari polysaccharides (HPS), and Runx-2

Radix Hedysari polysaccharides (HPS) is the principal active fraction of Radix Hedysari (RH). The information about HPS3d, the main fraction of HPS3, and its effect on bone is still unknown. In the present study, the purified HPS3d was obtained by anion-exchange column. It consisted of 94.38% polysaccharide, 3.40% protein and 13.30% uronic acid. The molecular weight was measured to be 84.6 kDa. The backbone consisted of galactopyranose and galacturonopyranose, and the side chains were composed of glucopyranose, rhamnopyranose and arabinofuranose. The FT-IR and elemental analysis showed that HPS3d was the sulfated polysaccharide. HPS3d upregulated alkaline phosphatase (ALP) activity and the expression of other osteogenic marker genes in osteoblast. In addition, HPS3d increased the expression and transcriptional activity of Runt-related transcription factor 2 (Runx-2) and Osterix, the two master genes of osteoblast differentiation. These findings suggest that HPS3d stimulates osteoblast differentiation by activation of Runx-2 and Osterix.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Microbiologie, Microbiology, Bactériologie, Bacteriology, Métabolisme. Enzymes, Metabolism. Enzymes, Bactérie, Bacteria, Micrococcales, Oside polymère, Oside polymer, Osido polímero, Streptococcaceae, Dextran, Etude expérimentale, Experimental study, Estudio experimental, Leuconostoc mesenteroides, Masse moléculaire, Molecular mass, Masa molecular, Morphologie, Morphology, Morfología, Mutation, Mutación, Origine microbienne, Microbial origin, Origen microbiano, Structure moléculaire, Molecular structure, Estructura molecular, Levane, Exopolysaccharide, and Levan

An exopolysaccharide known as dextran was produced by Leuconostoc mesenteroides KIBGE-IB22 (wild) and L. mesenteroides KIBGE-IB22M20 (mutant). The structure was characterized using FTIR, 1H NMR, 13C NMR and 2D NMR spectroscopic techniques, whereas surface morphology was analyzed using SEM. A clear difference in the spectral chemical shift patterns was observed in both samples. All the spectral data indicated that the exopolysaccharide produced by KIBGE-IB22 is a mixture of two biopolymers. One was dextran in α-(1 → 6) configuration with a small proportion of α-(1 → 3) branching and the other was levan containing β-(2 → 6) fructan fructofuranosyl linkages. However, remarkably the mutant only produced dextran without any concomitant production of levan. Study suggested that the property of KIBGE-IB22M20, regarding improved production of high molecular weight dextran in a shorter period of fermentation time without any contamination of other exopolysaccharide, could be employed to make the downstream process more feasible and cost effective on large scale.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs optoélectroniques, Optoelectronic devices, Dispositif optoélectronique, Optoelectronic device, Dispositivo optoelectrónico, Affinité électronique, Electron affinity, Afinidad electrónica, Autoabsorption, Self absorption, Autoabsorción, Brillance, Brightness, Brillantez, Brome, Bromine, Bromo, Centre accepteur, Acceptor center, Centro aceptor, Centre donneur, Donor center, Centro dador, Chlore, Chlorine, Cloro, Composé conjugué, Conjugated compound, Compuesto conjugado, Condensation, Condensación, Copolymère, Copolymer, Copolímero, Diode électroluminescente, Light emitting diode, Diodo electroluminescente, Dopage, Doping, Déplacement Stokes, Stokes shift, Desplazamiento Stokes, Encombrement stérique, Steric hindrance, Embarazo estérico, Lumière rouge, Red light, Luz roja, Masse moléculaire, Molecular mass, Masa molecular, Orbitale frontière, Frontier orbital, Orbital frontera, Polymère conjugué, Conjugated polymer, Polímero conjugado, Réticulation, Crosslinking, Reticulación, Semiconducteur, Semiconductor materials, Semiconductor(material), 8560J, Deep red to NIR light-emitting diodes, and Semiconductors

High molecular weight and non-crosslinking conjugated donor―acceptor copolymers with chlorine on the backbones were straight forward synthesized for the first time under Stille condensation reaction by using the different reaction activities between chlorine and bromine atoms. The chlorine-bearing polymers exhibited much lower LUMO, larger Stokes shift and lower self-absorption compared with the non-chloride analogue, for the electron affinity and large steric hindrance of chlorine atoms. Deep red to NIR emission centered at 698 nm was obtained with brightness about 1500 cd/m2 and centered at 708 nm was obtained with brightness over 400 cd/m2 based on dopant/host system.

Energy, Énergie, Geology, Géologie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Combustibles, Fuels, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Acide gras ester méthyle, Fatty acid methyl ester, Acido graso ester metilo, Biocarburant, Biofuel, Biocarburante, Carburant diesel, Diesel fuel, Carburante diesel, Composition chimique, Chemical composition, Composición química, Compressibilité, Compressibility, Compresibilidad, Densité, Density, Densidad, Incertitude, Uncertainty, Incertidumbre, Injection combustible, Fuel injection, Inyección combustible, Masse moléculaire, Molecular mass, Masa molecular, Mesure, Measurement, Medida, Méthode calcul, Computing method, Método cálculo, Performance, Rendimiento, Biodiesel, Correlation, and Speed of sound

The property changes associated with the differences in chemical composition of biodiesel may change the fuel injection timing which in turn cause different exhaust emissions and performance of engines. The property that has an important effect on the fuel injection timing is the speed of sound (related with isentropic bulk modulus). Despite the speed of sound of pure fatty acid (methyl and ethyl) esters being reasonably known in a wide range of temperature the experimental data for biodiesel are very scarce in the literature. In this work the speed of sound of six fatty acid methyl esters (FAME = laurate (MeC12:0), myristate (MeC14:0), palmitate (MeC16:0), stearate (MeC18:0), oleate (MeC18:1), linoleate (MeC18:2)) and six biodiesel fuel samples were measured using a non-intrusive ultrasonic methodology. The measurements for FAMEs were made at atmospheric pressure from a minimum of 288.15 K to a maximum of 353.15 K, and in the temperature range 298.15―353.15 K for biodiesel samples. The uncertainty of the measurements was estimated as less than ±1 m s-1. The speed of sound data combined with available density data from literature was used to calculate the isentropic compressibility and the molecular compressibility for the FAMEs and for the biodiesel samples. The results for molecular compressibility evidenced that this property is almost independent of the temperature in the temperature range of calculations both for FAMES and biodiesel. Linear relationships were established between the molar compressibility and the molecular weight for FAMES and biodiesel. The before mentioned behavior of molar compressibility face to temperature and molecular weight make it possible to develop prediction methods for the calculation of the speed of sound.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie chimique, Chemical engineering, Séparation par membrane (osmose inverse, dialyse...), Membrane separation (reverse osmosis, dialysis...), Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Angiospermae, Dicotyledones, Spermatophyta, Séparation physique, Physical separation, Separación física, Composé hydrosoluble, Water soluble compound, Compuesto hidrosoluble, Etude expérimentale, Experimental study, Estudio experimental, Feuille végétal, Plant leaf, Hoja vegetal, Fractionnement, Fractionation, Fraccionamiento, Juglandaceae, Masse moléculaire, Molecular mass, Masa molecular, Origine végétale, Plant origin, Origen vegetal, Oside polymère, Oside polymer, Osido polímero, Plante médicinale, Medicinal plant, Planta medicinal, Séparation par membrane, Membrane separation, Separación por membrana, Ultrafiltration, Ultrafiltración, Cyclocarya paliurus, Cyclocarya paliurus (Batal.) Iljinskaja, Membrane, Molecular weight, and Polysaccharide

In this study, ultrafiltration membrane process was employed to separate polysaccharides from Cyclocarya paliurus (Batal.) Iljinskaja (C. paliurus) to simulate industrial production. Meanwhile, the molecular weight distribution of C. paliurus polysaccharides was investigated by gel permeation chromatography. Four fractions were obtained and named as CPPS-A, CPPS-B, CPPS-C and CPPS-D, respectively. CPPS-A and CPPS-B contained approximately 69.5% and 12.7% of polysaccharides, whose molecular weight were in the range of 100-300 kDa and 120 kDa. respectively. CPPS-C was comprised of two polysaccharides with average molecular weight of 40 kDa and 15 kDa. Results showed that ultrafiltration resulted in the removal of parts of small molecule weight polysaccharides, the increase of proportion of high molecule weight ones and the obvious improvement of quality of products. Compared with ethanol precipitation and gel permeation chromatography techniques, ultrafiltration showed many advantages, and also provided theoretical support for industrial manufacturing of C. paliurus polysaccharides in separation.

Biomedical engineering, Génie biomédical, 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, Biomatériau, Biomaterial, Caprolactone polymère, Polycaprolactone, Caprolactona polímero, Dimension pore, Pore size, Dimensión poro, Echafaudage, Scaffold, Andamiaje, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Lactone polymère, Lactone polymer, Lactona polímero, Masse moléculaire, Molecular mass, Masa molecular, Polymère aliphatique, Aliphatic polymer, Polímero alifático, degradation, molecular weight, poly(caprolactone), pore size, and porogen

The major challenge in designing a scaffold for fabricating tissue engineered blood vessels is optimization of its microstructure for supporting uniform cellular in-growth with good mechanical integrity and degradation kinetics suitable for long-term implantation. In this study, we have investigated the feasibility of varying the pore size of poly(ε-caprolactone) (PCL) scaffold by altering the molecular weight of porogen and studied the effect of degradation on morphological characteristics and mechanical properties of scaffolds by correlating to the extent of degradation. Scaffolds with two different pore sizes were prepared by solvent casting and particulate leaching where poly(ethylene glycol) (PEG) porogens having two molecular weights (3400 and 8000) were used and subjected to in vitro degradation in phosphate buffered saline (PBS) upto six months. Microcomputed tomography studies of scaffolds revealed narrower pore size distribution when PEG-3400 was used as porogen and had 78% pores in the 12-24 μ range, whereas incorporation of PEG-8000 resulted in broader distribution with only 65% pores in the same range. Degradation resulted in scaffolds with narrower pore size distribution to have better retention of morphological and mechanical characteristics compared to scaffolds with broader distribution. Gravimetric and molecular weight studies also showed that scaffold degradation in both cases was only in initial stages after 6 months and PCL scaffolds had potential to be recommended for vascular tissue engineering applications.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Acide formique, Formic acid, Fórmico ácido, Chimie, Chemistry, Química, Combustible, Fuel, Hydrogène, Hydrogen, Hidrógeno, In situ, Lignine, Lignin, Lignina, Masse moléculaire, Molecular mass, Masa molecular, Polymérisation, Polymerization, Polimerización, De-polymerization, and Molecular weight

In this study, formic acid (FA) was employed as an in-situ hydrogen donor for the reductive de-polymerization of kraft lignin (KL). Under the optimum operating conditions, i.e., 300 °C, 1 h, 18.6 wt.% substrate concentration, 50/50 (v/v) water-ethanol medium with FA at a FA-to-lignin mass ratio of 0.7, KL (Mw ∼ 10,000 g/mol) was effectively de-polymerized, producing de-polymerized lignin (DL, Mw 1270 g/mol) at a yield of ∼90 wt.% and <1 wt.% yield of solid residue (SR). The Mw of the DL products decreased with increasing reaction temperature, time and FA-to-lignin mass ratio. The sulfur contents of all DL products were remarkably lower than that in the original KL. It was also demonstrated that FA is a more reactive hydrogen source than external hydrogen for reductive de-polymerization of KL.

Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Combustibles, Fuels, Pétrole et gaz. Produits pétroliers, Crude oil, natural gas and petroleum products, Traitement du pétrole brut et des dérivés liquides des schistes bitumineux et sables asphaltiques. Procédés. Equipements. Raffineries et unités de traitement, Processing of crude oil and oils from shales and tar sands. Processes. Equipment. Refinery and treatment units, Produits dérivés du pétrole et des schistes bitumineux. Produits finis, gaz, carburants, fuels, huiles et bitumes raffinés, Petroleum products, gas and fuels. Motor fuels, lubricants and asphalts, Distillation, Destilación, Masse moléculaire, Molecular mass, Masa molecular, Résidu pétrolier, Petroleum residue, Resíduo petrolero, TBP curve, molecular distillation, molecular weight, and petroleum residue

Molecular distillation process is an efficient way to separate complex residues to obtain improvement and a more complete characterization of crude oils. It presents advantages such as to generate distillation products that can be experimentally characterized, and the operation conditions of this process generate distillate cuts with an atmospheric equivalent boiling point (AEBP) above 650°C without risks of thermal degradation. The aim of this work is to carry out the separation of two vacuum residues (VR) within the process temperature range from 550 to 670°C, using the Brazilian Molecular Distillation equipment. As a result, five distillate cuts and five residues from molecular distillation processing were generated. The molecular distillation (MD) technique provided a gain in distillate yield of about 10% over the conventional methods. The efficiency of the technique was verified through the vapor pressure osmometry experiments and the extension of true boiling point (TBP) curves of petroleum. The extended TBP curves by the molecular distillation process demonstrated that this alternative method is appropriate to extend the TBP curves to temperatures above those of the conventional methods.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Bactérie lactique, Lactic acid bacteria, Bacteria láctica, Bactérie, Bacteria, Micrococcales, Streptococcaceae, Acide, Acids, Acido, Intracellulaire, Intracellular, Intracelular, Lactococcus lactis, Masse moléculaire, Molecular mass, Masa molecular, Précurseur, Precursor, Recombinaison, Recombination, Recombinación, Streptococcus equi subsp. zooepidemicus, Hyaluronic acid, MFA, Molecular weight, and Streptococcus zooepidemicus

HA molecular weight variation in Streptococcus zooepidemicus and two recombinant Lactococcus lactis strains were investigated by chemostat experiments and metabolic flux analysis (MFA). The study showed that intracellular flux ratio of UDP-GlcUA to UDP-ClcNAc correlated directly with HA molecular weight, for all the three strains. The ratio of intracellular concentration of these HA precursors also exhibited a similar trend. Phosphoglucoisomerase activity and glucose flux towards lactic acid formation were found to be the major bottlenecks for HA production in all the three strains. The study suggests that environmental conditions and genetic manipulations that balance the intracellular flux and HA precursors concentrations will result in increased molecular weight.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Métabolisme général et cellulaire. Vitamines, General and cellular metabolism. Vitamins, Immunomodulateurs, Immunomodulators, Invertebrata, Mammalia, Mollusca, Rodentia, Vertebrata, Activité biologique, Biological activity, Actividad biológica, Chromatographie, Chromatography, Cromatografía, Etude expérimentale, Experimental study, Estudio experimental, Extraction solvant, Solvent extraction, Extracción solvente, Foie, Liver, Hígado, Gastropoda, Hépatoprotecteur, Hepatoprotector, Immunostimulant, Immunostimulant agent, Inmunoestimulante, In vitro, In vivo, Macrophage, Macrófago, Masse moléculaire, Molecular mass, Masa molecular, Multiplication cellulaire, Cell proliferation, Multiplicación celular, Origine animale, Animal origin, Origen animal, Oside polymère, Oside polymer, Osido polímero, Phagocytose, Phagocytosis, Fagocitosis, Purification, Purificación, Souris, Mouse, Ratón, Splénocyte, Splenocyte, Esplenocito, Glossaulax didyma, Characterization, Hepatoprotective activity, and Immunostimulatory activity

In this study, purification, preliminary characterization, immunostimulatory and hepatoprotective activities of polysaccharides from Glossaulax didyma (GDPS) were investigated. Firstly, crude GDPS was purified by chromatography of DEAE-52 and Sephadex G-100, resulting in three purified fractions of GDPS-1. GDPS-2 and GDPS-3. The three fractions were mainly composed of glucose with the average molecular weight of 161, 197 and 204 kDa, respectively. GDPS-2 was quite different from GDPS-1 or GDPS-3. It had much higher contents of protein and sulfuric radical. For immunostimulatory activities in vitro, the three fractions could significantly stimulate the proliferation of splenocytes and enhance phagocytic activity of peritoneal macrophages. For hepatoprotective activity in vivo, the administration of GDPS significantly decreased the serum levels of alanine aminotransferase, aspartate aminotransferase and tumor necrosis factor-alpha, inhibited the formation of malondialdehyde and restored the liver activities of superoxide dismutase and glutathione peroxidase in Bacillus Calmette-Guerin/lipopolysaccharide-induced liver injury mice. The results suggested GDPS should be a potent natural polymer with immunostimulatory and hepatoprotective activities.