Search results for "surface area"

showing 10 items of 203 documents

Preparation and properties of poly(L-lactic acid) scaffolds by thermally induced phase separation from a ternary polymer-solvent system

2004

Poly(L-lactic acid) (PLLA) foams for tissue engineering were prepared via thermally induced phase separation of a ternary system PLLA/dioxane/tetrahydrofuran (THF) followed by double solvent exchange (water and ethyl alcohol) and drying. An extension to solidification from solution of a previously developed method for solidification from the melt was adopted. The technique is based on a continuous cooling transformation (CCT) approach, consisting in recording the thermal history experienced by rapidly cooled samples and then analyzing the resulting sample morphology. Different foams were produced by changing the relative amount of dioxane and THF in the starting solution while the amount of…

Ternary numeral systemMaterials scienceTissue EngineeringPolymers and PlasticsOrganic ChemistryPorosimetrylaw.inventionSolventCrystallinitychemistry.chemical_compoundchemistryChemical engineeringlawSpecific surface areaPolymer chemistryMaterials ChemistrySolvent effectsCrystallizationTetrahydrofuranPolymer International
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Rapid and eco-friendly synthesis of graphene oxide-silica nanohybrids

2014

The increasing interest in Graphene oxide (GO) is due to many issues: the presence of both sp2-conjugated atoms and oxygen-containing functional groups provides a strong hydrophilicity and the possibility to further functionalize it with other molecules (i.e. π-π interactions covalent attachment etc.) [1]. Furthermore since the GO is biocompatible and noncytotoxic many studies have been recently focused on the development of GO-based nanodevices for bioimaging DNA detection drug delivery. Due to their low cytotoxicity and large internal surface area silica nanoparticles have been taken into account as promising material for biolabeling and drug loading/delivery. Particular consideration has recently been demonstrated for GO-silica composites because of the potentialities for electrical applications their chemical inertia and stability toward ions exposure. The possibility to combine the extraordinary properties of GO and silica offers several advantages for the realization of nanoprobes for biological applications and of biosensor [12]. The strategy for the fabrication of GO-nanosilica nanohybrids can be schematized as follows: (i) synthesis of GO by oxidizing graphite powder with the method described by Marcano et al. [3] (ii) Preparation of oxygen-loaded silica nanoparticles by thermal treatments in controlled atmosphere in order to induce high NIR emission at 1272 nm from high purity silica nanoparticles. (iii) preparation of GrO-silica nanohybrid films via rapid solvent casting in water. The nanohybrids were tested by XPS FTIR Raman analysis UV photoluminescence analysis TGA Zeta potential measurements electrical tests AFM and SEM. Several nanohybrids were prepared by combining two different typologies of GO and two different samples of silica.
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Biomass-based composite catalysts for catalytic wet peroxide oxidation of bisphenol A : preparation and characterization studies

2019

Abstract The wet granulation process was used to prepare new, efficient, and cost-effective granular biomass-based composite catalysts for catalytic wet peroxide oxidation (CWPO) of bisphenol A (BPA). The most stable composite granules was prepared by mixing biomass-based carbon residue (CR) with metakaolin (MK) combined with calcium oxide (CaO) or cement and a solvent (NaOH or KOH). For all the prepared composite granules, the optimized binding agents to carbon ratio was 0.3, the solvent to carbon ratio 1.2, and the agitation rate 1200 rpm. The specific surface area of the prepared catalysts was 152–205 m2/g. The composite granular catalyst (CR + MK + CaO + NaOH) had the most durable and s…

Thermal desorption spectroscopybiomassacomposite catalystComposite numbergranular activated carbon02 engineering and technologyjätevesi010501 environmental sciences01 natural sciencesPeroxidewastewater purificationCatalysisGranulationchemistry.chemical_compoundSpecific surface areaChemical Engineering (miscellaneous)Calcium oxideWaste Management and Disposalta116komposiitit0105 earth and related environmental sciencesjäteveden käsittelybiomassProcess Chemistry and Technology021001 nanoscience & nanotechnologyPollutionSolventchemistryaktiivihiilioxidation of bisphenol A0210 nano-technologyNuclear chemistryJournal of Environmental Chemical Engineering
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Rapid synthesis of tin (IV) oxide nanoparticles by microwave induced thermohydrolysis

2008

Abstract Tin oxide nanopowders, with an average size of 5 nm, were prepared by microwave flash synthesis. Flash synthesis was performed in aqueous solutions of tin tetrachloride and hydrochloric acid using a microwave autoclave (RAMO system) specially designed by the authors. Energy dispersive X-ray analysis (EDX), X-ray powder diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analysis, nitrogen adsorption isotherm analysis, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM), were used to characterize these nanoparticles. Compared with conventional synthesis, nanopow…

Thermogravimetric analysisAnalytical chemistrychemistry.chemical_elementInfrared spectroscopyCondensed Matter PhysicsTin oxideFourier transform spectroscopyElectronic Optical and Magnetic MaterialsInorganic ChemistryDifferential scanning calorimetrychemistrySpecific surface areaMaterials ChemistryCeramics and CompositesPhysical and Theoretical ChemistryFourier transform infrared spectroscopyTinNuclear chemistryJournal of Solid State Chemistry
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Bentonite-ionic liquid composites for Congo red removal from aqueous solutions

2021

Abstract Clay-organic composites have attracted great interest due to their ability to remove various contaminants from wastewater. The surfactants are the most commonly used organic compounds for clay modification. However, cationic surfactants are toxic and can be environmentally hazardous. Ionic liquids are a new promising alternative to the cationic surfactants due to lesser toxicity and appropriate thermal stability. The research aim is to prepare an environmentally friendly new class of clay sorbents modified with ionic liquids for potential applications in wastewater treatment from the textile industry. Imidazolium-based ionic liquids with different lengths of alkyl chains were inter…

Thermogravimetric analysisAqueous solutionIon exchangeChemistrySorption02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesAtomic and Molecular Physics and Optics0104 chemical sciencesElectronic Optical and Magnetic MaterialsCongo redchemistry.chemical_compoundSpecific surface areaBentoniteIonic liquidMaterials ChemistryPhysical and Theoretical ChemistryComposite material0210 nano-technologySpectroscopyJournal of Molecular Liquids
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Structure and performance properties of environmentally-friendly biocomposites based on poly(ɛ-caprolactone) modified with copper slag and shale dril…

2018

The potential application of two types of industrial wastes, drill cuttings (DC) and copper slag (CS), as silica-rich modifiers of poly(ɛ-caprolactone) (PCL) was investigated. Chemical structure and physical properties of DC and CS fillers were characterized using X-ray diffractometer, X-ray fluorescence spectroscopy, particle size and density measurements. PCL/DC and PCL/CS composites with a variable content of filler (5 to 50 parts by weight) were prepared by melt compounding in an internal mixer. It was observed that lower particle size of DC filler enhanced processing of biocomposites comparing to CS filler. Smaller particles of DC filler and thus the higher specific surface area, enabl…

Thermogravimetric analysisEnvironmental EngineeringMaterials scienceScanning electron microscopeindustrial wastes02 engineering and technology010402 general chemistry01 natural sciencesCopper slagstructure-property relationshipsSpecific surface areaUltimate tensile strengthEnvironmental ChemistryComposite materialPorosityWaste Management and Disposalchemistry.chemical_classificationbiocompositesPolymer021001 nanoscience & nanotechnologyPollutionCopper slag0104 chemical sciencesdrill cuttingschemistryParticle size0210 nano-technologyvolatile organic compounds emissionsThe Science of the total environment
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Preparation and characterization of a novel chitosan/Al2O3/magnetite nanoparticles composite adsorbent for kinetic, thermodynamic and isotherm studie…

2015

Abstract In this study we developed a novel chitosan/Al 2 O 3 /magnetic iron oxide nanoparticle composite acting as an adsorbent for removing Methyl Orange (MO), a model anionic dye, from aqueous solution. The new adsorbent was characterized by Scanning Electron Microscope (SEM), Thermo Gravimetric Analysis (TGA), Brunauer–Emmett–Teller (BET) specific surface area, Energy Dispersive spectrometer (EDAX), powder X-ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) methods. The MO removal by the developed adsorbent was investigated using batch adsorption technique and all parameters influencing the removal efficiency such as: dose of adsorbent, pH and initial MO concentr…

Thermogravimetric analysisMaterials scienceGeneral Chemical EngineeringInorganic chemistryta221AluminaIndustrial and Manufacturing Engineeringsymbols.namesakechemistry.chemical_compoundAdsorptionDesorptionSpecific surface areaMethyl orangeEnvironmental ChemistryFourier transform infrared spectroscopyta116ChitosanAqueous solutionLangmuir adsorption modelGeneral ChemistryX-ray diffractionMethyl OrangechemistrysymbolsIron oxide nanoparticleAdsorptionNuclear chemistryChemical Engineering Journal
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Ceria-based electrolytes prepared by solution combustion synthesis: The role of fuel on the materials properties

2016

Ce0.8Sm0.2O2 − xpowders were synthesized by solution combustion synthesis using citric acid, cellulose and sucrose as single, or intimately mixed, fuels. The powders were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, N2sorption at −196 °C, H2-temperature programmed reduction and thermogravimetric analyses. Textural properties of the powders were shaped by the peculiar employed fuel. The study of reducibility revealed that oxygen vacancies formation is mainly influenced by both parameters, specific surface area and total pore volume. The different tendency toward reduction played a key role in sintering under reducing atmosphe…

Thermogravimetric analysisMaterials scienceScanning electron microscopeInorganic chemistrySintering02 engineering and technology010402 general chemistry01 natural sciencesCatalysisCatalysiSpecific surface areaTemperature-programmed reductionSolution combustion synthesiGeneral Environmental ScienceIT-SOFC2300Reducing atmosphereProcess Chemistry and TechnologySamarium doped ceria021001 nanoscience & nanotechnologyMicrostructureSintering in reducing atmosphere0104 chemical sciencesDielectric spectroscopyIT-SOFC; Reducibility; Samarium doped ceria; Sintering in reducing atmosphere; Solution combustion synthesis; Catalysis; 2300; Process Chemistry and TechnologyChemical engineeringSolution combustion synthesisSettore CHIM/03 - Chimica Generale E Inorganica0210 nano-technologyReducibility
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Gravimetric characterisation of the surface properties of a porous drug carrier

1995

The gas adsorption method is the most common means to characterise the topology of solid surfaces with regard to its use as an adsorbent. Adsorption isotherms are determined advanta-geously using a vacuum microbalance: Thermogravimetric techniques allow the observation of sample degassing and its optimization. The dry mass is determined in situ, the mass of gas adsorbed is measured directly and different gases can be used without calibration. From the isotherm the pore size distributions, specific surface area, fractal dimension and density can be derived. Commercially available gravimetric sorption apparata and vacuum balances as well as software for data evaluation are reviewed in tables.…

ThermogravimetryMatrix (chemical analysis)Thermogravimetric analysisMaterials scienceAdsorptionSpecific surface areaAnalytical chemistryGravimetric analysisSorptionPorosityJournal of Thermal Analysis
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Differential Effects of Biologics on Psoriasis-Related Vascular Inflammation and Risk of Thrombosis

2020

Programa Estatal de I+D+i Orientada a los Retos de la Sociedad from Ministerio de Ciencia, Innovación y Universidades and European Regional Development Fund (Spain) [RTI2018-094436-B-I00]; Ministerio de Sanidad y Consumo CIBERehd (Spain) [CB06/04/0071]; Generalitat Valenciana (Spain) [PROMETEO/2018/141]; Proyectos Grupos Emergentes [GV/2019/043]; and Universidad Europea (Spain) (2018/UEM32 and 2019/UEM29]. 8.551 JCR (2020) Q1, 4/69 Dermatology 1.951 SJR (2020) Q1, 54/438 Biochemistry No data IDR 2020 UEV

Vasculitis0301 basic medicinemedicine.medical_specialtyEnfermedad cardiovascularImiquimodCell CommunicationDermatologyBiochemistryMiceTrombosis03 medical and health sciences0302 clinical medicinePsoriasis Area and Severity IndexPsoriasisProductos biológicosLeukocytesmedicineAnimalsHumansPsoriasisMolecular BiologyBody surface areaBiological ProductsImiquimodTumor Necrosis Factor-alphabusiness.industryEndothelial CellsThrombosisCell BiologyDermatology Life Quality Indexmedicine.diseaseDermatologyThrombosis030104 developmental biology030220 oncology & carcinogenesisMethotrexatebusinessEnfermedad de la pielMacemedicine.drugJournal of Investigative Dermatology
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