Search results for " solution"

showing 10 items of 3084 documents

Task-specific ionic liquid for the depolymerisation of starch-based industrial waste into high reducing sugars

2014

Development of a simple route for the catalytic conversion of starch-based industrial waste (potato peels) and potato starch into reducing sugars was investigated in two ionic liquids for comparison – 1-allyl-3-methylimidazolium chloride [AMIM]Cl and 1-(4-sulfobutyl)-3-methylimidazolium chloride [SBMIM]Cl. Over a two hour period, a 20 wt% solution containing up to 43% and 98% of reducing sugars at low temperature in aqueous [SBMIM]Cl was achieved for the starch-based waste and the potato starch, respectively. In addition, the use of microwave and low frequency ultrasound to perform the depolymerisation of the raw starch-based material was explored and compared with conventional heating proc…

[SDE] Environmental ScienceshydrolyysiStarchtask-specific ionic liquidsultrasoundsChlorideCatalysisIndustrial wasteCatalysismikroaallotchemistry.chemical_compoundHydrolysis[CHIM] Chemical Sciencesmedicine[CHIM]Chemical SciencesOrganic chemistryta116Potato starchComputingMilieux_MISCELLANEOUScarbohydrates reducing sugarsAqueous solutionGeneral Chemistry6. Clean waterchemistry[SDE]Environmental SciencesIonic liquidNuclear chemistrymedicine.drugCatalysis Today
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Pd-Cu catalysts supported on anion exchange resin for the simultaneous catalytic reduction of nitrate ions and reductive dehalogenation of organochlo…

2019

International audience; The present work proposes the simultaneous removal of these classes of pollutants by a catalytic hydrotreatment processes. For this purpose, bimetallic Pd-Cu catalysts (with mass ratio Pd:Cu of 4:1) supported on macroporous strong base anion resin were prepared by different methods. The catalysts were characterized (by XRD, SEMEDX, XPS, AAS and H-2 chemisorption) and tested in a continuous flow system. The selected catalyst preparation protocol consists in a two-step method, which implies the deposition of palladium by ion exchange and the subsequent deposition of copper by controlled reaction on the surface of the pre-reduced palladium. The effectiveness of the cata…

[SDV]Life Sciences [q-bio]Inorganic chemistrypd-cu catalystchemistry.chemical_element010402 general chemistry7. Clean energy01 natural sciencesCatalysisCatalysis[CHIM]Chemical SciencesIon-exchange resinBimetallic stripComputingMilieux_MISCELLANEOUShydrodechlorinationAqueous solutionIon exchange010405 organic chemistryChemistryProcess Chemistry and Technologyanion exchange resinSelective catalytic reductionwater treatmentnitrate reduction0104 chemical sciences13. Climate actionChemisorptionPalladiumApplied Catalysis A: General
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Structural and hydrogenation study on the ball milled TiH2–Mg–Ni

2015

International audience; With the aim of further understanding for TieNieMg alloys and their hydrogenation behavior, powders of TiH2, Mg and Ni with the molar ratio of 3:1:2 have been mechanically milled for 10 h, 20 h, 30 h, 40 h according to the stoichiometry (TiH2)1.5Mg0.5Ni. Microstructures of the milled sample were analyzed and their hydrogenation properties as negative electrodes for Ni-MH batteries were studied. Phase change with milling time revealed the fast formation of the Ti-Mg-H FCC phase. The alloying priority among Ti, Mg and Ni was demonstrated by comparing phase compositions in different milling time. Hydrogen capacities evaluated by both solidegas reaction and electrochemic…

[SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph]Materials scienceHydrogenRenewable Energy Sustainability and the EnvironmentMetallurgyEnergy Engineering and Power Technologychemistry.chemical_elementHydrogen storageCondensed Matter PhysicsMicrostructureElectrochemistry[SPI.MAT]Engineering Sciences [physics]/MaterialsHydrogen storageFuel TechnologyChemical engineeringchemistryNi-MH Ti–MgElectrodeMetal hydrideTitrationMechanical alloying[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/MicroelectronicsStoichiometrySolid solutionInternational Journal of Hydrogen Energy
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The mKdV equation and multi-parameters rational solutions

2021

Abstract N -order solutions to the modified Korteweg–de Vries (mKdV) equation are given in terms of a quotient of two wronskians of order N depending on 2 N real parameters. When one of these parameters goes to 0, we succeed to get for each positive integer N , rational solutions as a quotient of polynomials in x and t depending on 2 N real parameters. We construct explicit expressions of these rational solutions for orders N = 1 until N = 6 .

[SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph][PHYS]Physics [physics]Pure mathematicsApplied MathematicsRational solutionsGeneral Physics and Astronomy[SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]01 natural sciences010305 fluids & plasmasComputational MathematicsNonlinear Sciences::Exactly Solvable and Integrable SystemsIntegerWronskiansModeling and Simulation0103 physical sciencesOrder (group theory)mKdV equation010301 acousticsQuotientMathematicsWave Motion
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Gustatory evoked cortical activity in humans in response to saccharin stimuli

2014

National audience; Introduction/Objectives: Gustatory Evoked Potentials (GEP) can be detected in response to an intermittent stimulation of the gustatory receptors by a primary flavour. Contrary the other evoked cortical potentials (visual, auditory or sensory), GEP have not been extensively studied due to their recording heterogeneity. Our aim was to establish a reliable recording of GEP in Humans. Methods: Voluntary and healthy subjects were included in this experiment. A saccharin solution with several concentrations (5, 10 or 20g per 100mL) was used as the gustatory stimulus. Each session was performed on a different day, with an interval of at least 2 hours after eating or drinking. Co…

[SPI.GPROC] Engineering Sciences [physics]/Chemical and Process Engineering[SDV.IDA]Life Sciences [q-bio]/Food engineeringsaccharin solutiongustatory evoked potentials[SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering[SDV.IDA] Life Sciences [q-bio]/Food engineering
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Reliable numerical solution of a class of nonlinear elliptic problems generated by the Poisson-Boltzmann equation

2020

We consider a class of nonlinear elliptic problems associated with models in biophysics, which are described by the Poisson-Boltzmann equation (PBE). We prove mathematical correctness of the problem, study a suitable class of approximations, and deduce guaranteed and fully computable bounds of approximation errors. The latter goal is achieved by means of the approach suggested in [S. Repin, A posteriori error estimation for variational problems with uniformly convex functionals. Math. Comp., 69:481-500, 2000] for convex variational problems. Moreover, we establish the error identity, which defines the error measure natural for the considered class of problems and show that it yields computa…

a priori error estimatesClass (set theory)Correctness010103 numerical & computational mathematics01 natural sciencesMeasure (mathematics)guaranteed and efficient a posteriori error boundsFOS: MathematicsApplied mathematicsPolygon meshMathematics - Numerical Analysis0101 mathematicserror indicators and adaptive mesh refinementMathematicsNumerical AnalysisApplied MathematicsRegular polygonNumerical Analysis (math.NA)convergence of finite element approximationsLipschitz continuity010101 applied mathematicsComputational MathematicsNonlinear systemexistence and uniqueness of solutionssemilinear partial differential equations65J15 49M29 65N15 65N30 65N50 35J20MathematikA priori and a posterioriPoisson-Boltzmann equationdifferentiaaliyhtälöt
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Steady‐state solutions of the aerotaxis problem

2022

We study the steady-state system of aerotaxis equations in higher dimensions.It is shown that the existence and multiplicity of solutions depend on the totalmass of the colony of bacteria, the energy function, and the boundary conditions.

aerotaxis equationsGeneral MathematicsGeneral Engineeringstationary solutionsnonlocal elliptic problemsMathematical Methods in the Applied Sciences
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REMOVAL OF BITTER COMPOUNDS FROM CITRUS BYPRODUCTS

2013

Bitter compounds such as limonoids, which consist of oxygenated triterpenoid compounds, are present in citrus fruits. Removal of limonoids from citrus fruits is of considerable importance for the citrus industry. Researchers have removed limonoids from citrus fruits and citrus byproducts using organic solvents. The objective of this study was to use a simpler method to remove limonoids from citrus byproducts.

alkaline solution citrus byproducts extraction limonoidsExtractionSettore AGR/15 - Scienze E Tecnologie AlimentariLimonoidsAlkaline solution; Citrus byproducts; Extraction; Limonoids; Food ScienceAlkaline solutionCitrus byproductsFood Science
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Photocrosslinking of dextran and polyaspartamide derivatives: a combination suitable for colon-specific drug delivery.

2007

Abstract The aim of this study was to prepare and characterize novel hydrogels with polysaccharide–polyaminoacid structure, able to undergo an enzymatic hydrolysis in the colon and potentially useful for treating inflammatory bowel diseases (IBD). Starting materials were methacrylated dextran (DEX-MA) and methacrylated α,β-poly(N-2-hydroxyethyl)- dl -aspartamide (PHM). These polymers were photocrosslinked by exposure of their aqueous solutions at 313 nm without photoinitiators. Different samples, shaped as microparticles, were obtained as a function of polymer concentration and irradiation time. FT-IR analysis confirmed the occurrence of a co-crosslinking between DEX-MA and PHM in all exper…

alpha; beta-poly(n-2-hydroxyethyl)-dl-aspartamide; biodegradable hydrogels; colon drug delivery; dextran; photocrosslinking; α; β-poly(n-2-hydroxyethyl)-dl-aspartamidealphaCell SurvivalColonPhotochemistryDrug CompoundingαPharmaceutical ScienceDosage formchemistry.chemical_compoundDrug StabilityEnzymatic hydrolysismedicineCell AdhesionOrganic chemistryHumansParticle Sizeβ-poly(n-2-hydroxyethyl)-dl-aspartamideDrug CarriersChromatographyDextranaseAqueous solutionChemistryHydrolysisbiodegradable hydrogelstechnology industry and agriculturecolon drug deliveryBeclomethasoneMucinsDextransHydrogelsHydrogen-Ion ConcentrationDextranCross-Linking Reagentsbeta-poly(n-2-hydroxyethyl)-dl-aspartamidedextranDrug deliverySelf-healing hydrogelsMethacrylatesSwellingmedicine.symptomphotocrosslinkingCaco-2 CellsPeptidesJournal of controlled release : official journal of the Controlled Release Society
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The young hard active Sun: soft X-ray irradiation of tryptophan in water solutions

2010

AbstractThe X-ray emission of the young Sun was much harder and intense than today and might have played a significant role in the evolution of complex organics in protoplanetary environments. We investigate the effects of soft X-rays on tryptophan molecules in aqueous solutions at room temperature. As results of the irradiation experiments we detect several light species indicative of fragmentation, together with large molecular structures such as tryptophan dipeptide and tripeptide. Complexification is more evident in H2O solution than in D2O, probably due to isotopic effects. The abundances of peptides depend on the irradiation dose and decrease with increasing energy deposition. Radical…

amino acidsAqueous solutionDipeptidePhysics and Astronomy (miscellaneous)RadicalastrobiologyTryptophanTripeptidePhotochemistryorigin of lifeX-ray irradiation of amino acidsCrystallographychemistry.chemical_compoundchemistryFragmentation (mass spectrometry)Space and Planetary Scienceamino acids astrobiology chemical evolution origin of life X-ray irradiation of amino acids.Earth and Planetary Sciences (miscellaneous)MoleculeIrradiationchemical evolutionEcology Evolution Behavior and SystematicsInternational Journal of Astrobiology
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