Search results for "Note"

showing 10 items of 10709 documents

Application of Nanoemulsions in the Synthesis of Nanoparticles

2018

Abstract Nanodroplets of a liquid in another immiscible liquid provide confined spaces in which chemical reactions can take place. If these reactions lead to the formation of nanoparticles, as it is the case for polymerization or precipitation reactions, nanodroplets can be used as templates for particle synthesis. The most common example of application of nanoemulsions for particle synthesis is the preparation of polymer nanoparticles by miniemulsion polymerization, but also inorganic materials can be produced in this way. Nanoemulsions are as well an excellent platform for preparing polymer/inorganic hybrid nanoparticles, either by using directly the templating effect of droplets during t…

chemistry.chemical_classificationMaterials scienceNanoparticle02 engineering and technologyPolymer010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesChemical reaction0104 chemical sciencesMiniemulsionTemplateChemical engineeringPolymerizationchemistryParticle0210 nano-technologyConfined space
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Polymer brushes under flow and in other out-of-equilibrium conditions

2011

Polymer brushes are formed from flexible linear macromolecules tethered at one chain end to a solid substrate, forming a dense polymeric layer of polymer chains which are more or less stretched in the direction perpendicular to the substrate surface. These systems find interest also due to numerous applications (colloid stabilization, improvement of lubrication properties when the surfaces are exposed to shear, protection of the surface against adsorption of nanoparticles or proteins, etc.), for which often the dynamic non-equilibrium response of these brushes to external perturbation is important. The present review summarizes recent computer simulation studies pertinent to these questions…

chemistry.chemical_classificationMaterials scienceNanoparticleNanotechnologyGeneral ChemistryPolymerCondensed Matter PhysicsColloidAdsorptionchemistryChemical physicsLubricationPerpendicularScalingMacromoleculeSoft Matter
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Magnetic molecular nanostructures: Design of magnetic molecular materials as monolayers, multilayers and thin films

2007

In this paper we summarize the importance and versatility of the molecular approach in the design and development of novel magnetic molecular materials. These materials processing, in order to obtain controlled molecular structures at the nanoscale, will also be remarked.

chemistry.chemical_classificationMaterials scienceNanostructureGeneral Physics and AstronomyNanotechnologySurfaces and InterfacesGeneral ChemistryCondensed Matter PhysicsSurfaces Coatings and FilmsCoordination complexNanolithographychemistryMonolayerMoleculeSelf-assemblyThin filmNanoscopic scaleApplied Surface Science
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Effect of the supramolecular interactions on the nanostructure of halloysite/biopolymer hybrids: A comprehensive study by SANS, fluorescence correlat…

2020

The structural properties of halloysite/biopolymer aqueous mixtures were firstly investigated by means of combining different techniques, including small-angle neutron scattering (SANS), electric birefringence (EBR) and fluorescence correlation spectroscopy (FCS). Among the biopolymers, non-ionic hydroxypropylcellulose and polyelectrolytes (anionic alginate and cationic chitosan) were selected. On this basis, the specific supramolecular interactions were correlated to the structural behavior of the halloysite/biopolymer mixtures. SANS data were analyzed in order to investigate the influence of the biopolymer adsorption on the halloysite gyration radius. In addition, a morphological descript…

chemistry.chemical_classificationMaterials scienceNanostructureSupramolecular chemistryGeneral Physics and AstronomyFluorescence correlation spectroscopyHalloysite02 engineering and technologyPolymerengineering.material010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesHalloysitePolyelectrolyte0104 chemical sciencesAdsorptionChemical engineeringchemistryengineeringBiopolymerPhysical and Theoretical Chemistry0210 nano-technology
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Defects and defect engineering in Soft Matter.

2020

Soft matter covers a wide range of materials based on linear or branched polymers, gels and rubbers, amphiphilic (macro)molecules, colloids, and self-assembled structures. These materials have applications in various industries, all highly important for our daily life, and they control all biological functions; therefore, controlling and tailoring their properties is crucial. One way to approach this target is defect engineering, which aims to control defects in the material's structure, and/or to purposely add defects into it to trigger specific functions. While this approach has been a striking success story in crystalline inorganic hard matter, both for mechanical and electronic properti…

chemistry.chemical_classificationMaterials scienceNanotechnology02 engineering and technologyGeneral ChemistryPolymerConjugated system010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsBranching (polymer chemistry)01 natural sciences0104 chemical sciencesSupramolecular polymerschemistryLiquid crystalDendrimerAmphiphileSoft matter0210 nano-technologySoft matter
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Polymer Complexes in Biological Applications

2013

This chapter summarizes the influence of polyelectrolyte topology on biological functions and biomedical applications such as cell uptake, drug delivery, and gene transfection. Polyelectrolytes utilized are spherical structures derived from dendrimers and albumin or cylindrical brushes, all of which are decorated with various polypeptide chains.

chemistry.chemical_classificationMaterials scienceNanotechnologyPolymerHuman serum albuminPolyelectrolyteCaveolae-mediated endocytosisPlasmid dnachemistryDendrimerDrug deliverymedicineOrganic chemistryTopology (chemistry)medicine.drug
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Recent Applications of Carbonaceous Nanosorbents in Solid Phase Extraction for the Determination of Pesticides in Food Samples

2018

This article covers recent trends of carbonaceous nanomaterial supported solid phase extraction for the liquid and gas chromatography analysis of pesticides in food samples. Several advanced carbonaceous nanosorbents have been reported over the previous decade for pesticide extraction, such as graphene derivatives modified by combination with silica, amines, polymers, and/or magnetic nanoparticles. The advances in this field have opened possibilities for using neat or modified carbon nanotubes or graphene-type sorbents for the pre-concentration of polar or nonpolar pesticides by solid phase extraction (SPE) or micro-SPE methods or to apply such nanomaterials for the removal of matrix compon…

chemistry.chemical_classificationMaterials scienceNanotubes CarbonSolid Phase Extraction010401 analytical chemistryExtraction (chemistry)Food Contamination02 engineering and technologyPolymer021001 nanoscience & nanotechnology01 natural sciences0104 chemical sciencesAnalytical ChemistryNanomaterialsMatrix (chemical analysis)chemistryChemical engineeringMagnetic nanoparticlesSolid phase extractionGas chromatographyPesticides0210 nano-technologyReusabilityCritical Reviews in Analytical Chemistry
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Dicyanobenzothiadiazole Derivatives Possessing Switchable Dielectric Permittivities

2017

Benzothiadiazoles are important electron acceptors and are frequently employed as electron-deficient components of donor-acceptor polymers. We report the effect of nitrile functionalities on the reactivity, steric hindrance, optoelectronic properties, and dielectric permittivity in dicyanobenzothioadiazole (DCNBT). Dielectric spectroscopy in the bulk and in solution assisted by DFT-calculations revealed that these molecules can be engineered to engender maximum values of the dipole moment and of dielectric permittivity due to the strong electron-withdrawing effect of the nitrile groups. The self-assembly in the bulk was investigated by X-ray scattering performed on single crystals, fibers (…

chemistry.chemical_classificationMaterials scienceNitrileRelative permittivity02 engineering and technologyPolymerDielectric010402 general chemistry021001 nanoscience & nanotechnology01 natural sciences0104 chemical sciencesDielectric spectroscopyDipolechemistry.chemical_compoundchemistryChemical physicsLiquid crystalPhase (matter)Organic chemistryGeneral Materials Science0210 nano-technologyACS Applied Materials & Interfaces
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Minimizing geminate recombination losses in small-molecule-based organic solar cells

2019

Small-molecule-based organic solar cells (OSCs) are a recurrent alternative to polymer-based OSCs. Due to the higher purity and definition of small molecules compared to polymers, the morphological requirements can be more relaxed. Here, we present a series of novel rhodanine-based small-molecule electron donors and blend them with the standard acceptor PC70BM. By performing a target analysis on femtosecond spectroscopy data, we quantify the rates of geminate charge recombination. We are able to reproduce these rates by applying the Marcus–Levich–Jortner equation, using results from quantum chemical calculations. This shows that in a series of differently substituted compounds, one can corr…

chemistry.chemical_classificationMaterials scienceOrganic solar cellPhotovoltaic systemQuímica orgánicafood and beverages02 engineering and technologyGeneral ChemistryPolymerElectron010402 general chemistry021001 nanoscience & nanotechnology7. Clean energy01 natural sciencesSmall moleculeAcceptor0104 chemical scienceschemistryChemical physicsMaterials ChemistryCyclic voltammetry0210 nano-technologyFemtochemistryJournal of Materials Chemistry C
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Multicomponent solid dispersion a new generation of solid dispersion produced by spray-drying

2020

Abstract The term “multicomponent solid dispersion” is widely used in recent literature to describe solid formulations consisting of a special excipient's mixture and active molecules finely dispersed. However, this term has not yet been defined. In this review, we aimed to improve the definition of multicomponent solid dispersions as a new generation of solid dispersions capable to improve both formulation issues and the therapeutic effect of the final dosage form. As it is well-known the use of solid dispersions to improve drug dissolution rate and solubility, this review describes the field of solid dispersions as well as the formulation strategies available for their production. In part…

chemistry.chemical_classificationMaterials sciencePharmaceutical ScienceExcipient02 engineering and technologyPolymer021001 nanoscience & nanotechnology030226 pharmacology & pharmacyDosage form03 medical and health sciences0302 clinical medicineChemical engineeringchemistrySpray dryingmedicineDissolution testingSolubility0210 nano-technologyDispersion (chemistry)Multicomponent solid dispersion Spray-drying Dissolution rates Dosage form Polymersmedicine.drugJournal of Drug Delivery Science and Technology
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