Search results for " Emission"

showing 10 items of 1496 documents

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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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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Analysis of archaeological samples and local clays using ICP-AES, TG–DTG and FTIR techniques

2000

Abstract The spectrochemical and thermal analysis of different archaeological samples as bricks, terra-cotta and local clays were carried out. The concentration of major and minor elements of samples was determined by sequential inductively coupled plasma atomic emission spectrometry. The method was tested by determining Si, Al, Fe, Ca, Mg, Mn, Pb, Cu, Zn, Ti, Na and K in the standard solutions and reference material GXR-4. The precision of the determination (relative standard deviation) ranged from 0.4 to 1.54%. The clay minerals are the main materials for the production of bricks and terra-cotta figures. Thermogravimetric (TG) and differential (TG–DTG) analysis and Fourier transform infra…

Thermogravimetric analysisEvolved gas analysisChemistryInductively coupled plasma atomic emission spectroscopyAnalytical chemistryFourier transform infrared spectroscopyStandard solutionInductively coupled plasmaClay mineralsThermal analysisArchaeologyAnalytical ChemistryTalanta
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Precursor Polymers for the Carbon Coating of Au@ZnO Multipods for Application as Active Material in Lithium-Ion Batteries

2014

The synthesis of statistical and block copolymers based on polyacrylonitrile, as a source for carbonaceous materials, and thiol-containing repeating units as inorganic nanoparticle anchoring groups is reported. These polymers are used to coat Au@ZnO multipod heteroparticles with polymer brushes. IR spectroscopy and transmission electron microscopy prove the successful binding of the polymer onto the inorganic nanostructures. Thermogravimetric analysis is applied to compare the binding ability of the block and statistical copolymers. Subsequently, the polymer coating is transformed into a carbonaceous (partially graphitic) coating by pyrolysis. The obtained carbon coating is characterized by…

Thermogravimetric analysisMaterials sciencePolymers and PlasticsPolymersInorganic chemistryAcrylic ResinsMetal NanoparticlesInfrared spectroscopyNanoparticleLithiumengineering.materialchemistry.chemical_compoundsymbols.namesakeElectric Power SuppliesMicroscopy Electron TransmissionCoatingMaterials ChemistryElectrodesIonschemistry.chemical_classificationOrganic ChemistryPolyacrylonitrileSpectrometry X-Ray EmissionElectrochemical TechniquesPolymerCarbonchemistryengineeringsymbolsGoldZinc OxideRaman spectroscopyPyrolysisMacromolecular Rapid Communications
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Combining in the melt physical and biological properties of poly(caprolactone) and chlorhexidine to obtain antimicrobial surgical monofilaments.

2012

Bacterial infections on a sutured wound represent a critical problem, and the preparation of suture threads possessing antimicrobial properties is valuable. In this work, poly(caprolactone) (PCL) monofilaments were compounded at the concentration of 1, 2 and 4 % (w/w), respectively, to the antiseptic chlorhexidine diacetate (CHX). The incorporation was carried out in the melt by a single-step methodology, i.e. “online” approach. Mechanical tests revealed that the incorporation of CHX does not significantly change tensile properties of PCL fibres as the thermal profile adopted to prepare the compounded fibres does not compromise the antibacterial activity of CHX. In fact, CHX confers to comp…

Thermoplasticmedicine.drug_classCell SurvivalPolyestersSettore BIO/19 - Microbiologia GeneraleApplied Microbiology and Biotechnologychemistry.chemical_compoundAntisepticTensile StrengthPolymer chemistryUltimate tensile strengthmedicineEscherichia coliHumanschemistry.chemical_classificationpoly(caprolactone)biologyChemistryChlorhexidinechlorhexidineChlorhexidineSuture TechniquesSpectrometry X-Ray EmissionGeneral MedicineFibroblastsbiology.organism_classificationAntimicrobialMicrococcus luteusSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialiEquipment and Suppliessurgical monofilamentsAnti-Infective Agents LocalMicroscopy Electron ScanningMicrococcus luteusAntibacterial activityCaprolactoneBiotechnologyNuclear chemistrymedicine.drugBacillus subtilisApplied microbiology and biotechnology
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Positronen-Emissions-Tomographie zum präoperativen Staging des Ösophaguskarzinoms

2002

BACKGROUND AND OBJECTIVE Exact preoperative staging is a prerequisite for the indication as well as the choice of the appropriate operative technique for patients with esophageal carcinoma. In this prospective study we assessed whether positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) increases the accuracy of staging compared to standard computer tomography (CT) and leads to a different therapeutic approach. PATIENTS AND METHODS 30 patients (25 men, 5 women, median age 63 years) with histologically identified carcinoma of the esophagus (n =29) and the cardia (n = 1), respectively, were studied. All patients underwent FDG-PET imaging of the neck, chest, and abdomen as w…

Thoraxmedicine.diagnostic_testbusiness.industryGeneral Medicinemedicine.diseasemedicine.anatomical_structureLymphatic systemPositron emission tomographymedicineCarcinomaAbdomenEsophagusbusinessNuclear medicineProspective cohort studyLymph nodeDMW - Deutsche Medizinische Wochenschrift
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72/74As-labeling of HPMA based polymers for long-term in vivo PET imaging

2010

Abstract In the context of molecular imaging, various polymers based on the clinically approved N-(2-hydroxypropyl)-methacrylamide (HPMA) have been radio-labeled using longer-living positron emitters 72As t1/2 = 26 h or 74As t1/2 = 17.8 d. This approach may lead to non-invasive determination of the long-term in vivo fate of polymers by PET (positron emission tomography). Presumably, the radio label itself will not strongly influence the polymer structure due to the fact that the used nuclide binds to already existing thiol moieties within the polymer structure. Thus, the use of additional charges or bulky groups can be avoided.

Time FactorsClinical BiochemistryPharmaceutical ScienceContext (language use)BiochemistryArsenicIn vivoDrug DiscoveryPolymer chemistrymedicineMolecular BiologyRadioisotopeschemistry.chemical_classificationAcrylamidesmedicine.diagnostic_testOrganic ChemistryArsenic isotopePositron emittersPolymerPet imagingchemistryPositron emission tomographyPositron-Emission TomographyBiophysicsMolecular MedicineMolecular imagingBioorganic & Medicinal Chemistry Letters
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Cavités plasmoniques et nanosources optiques

2013

Optical microcavities exhibit high resonance quality, so that, they are of key interest for the design of low-threshold lasers or for achieving strong coupling regime. But, such systems support modes whose the volume remain diffraction limited.In this manuscript, we are interested in their plasmonic counterparts because they support confined modes at the sub-wavelength scale. First, we study an in-plane plasmonic cavity which is the transposition of 1D optical cavity to surface wave. We characterize the cavity by measuring the fluorescence lifetime of dye molecules deposited inside.Then, we are interested in 3-dimension mode confinement achieved by spherical metal nanoparticles. We discuss …

Time-resolved spectroscopyCavité plasmonique[SPI.OTHER]Engineering Sciences [physics]/Other[ SPI.OTHER ] Engineering Sciences [physics]/Other[SPI.OTHER] Engineering Sciences [physics]/OtherSpontaneous emissionSpectroscopie résolue en tempsLocalized surface plasmon[ PHYS.COND.CM-GEN ] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other]Plasmonic cavity[PHYS.COND.CM-GEN] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other][PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other]Émission spontanéePlasmon de surface localisé
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Metabolic mapping with bioluminescence: basic and clinical relevance

2002

This review is focused on metabolic mapping in biological tissue with quantitative bioluminescence and single photon imaging. Metabolites, such as ATP, glucose and lactate, can be imaged quantitatively and within microscopic dimensions in cryosections from shock frozen biological specimens using enzyme reactions and light emission by luciferases. The technique has been applied in numerous targets and models of experimental biomedical research, such as multicellular spheroids, various organs of laboratory animals in a physiological or pathophysiological state, and even in plant seeds. Among numerous other aspects, data obtained with this method have contributed to the elucidation of mechanis…

Tomography Emission-Computed Single-PhotonPathologymedicine.medical_specialtyCellBioengineeringIn situ hybridizationBiologymedicine.diseaseMalignancyMetastasismedicine.anatomical_structurePredictive Value of TestsNeoplasmsLuminescent MeasurementsImmunologyBiomarkers TumormedicineHumansBioluminescence imagingBioluminescenceImmunohistochemistryLight emissionMolecular BiologyBiotechnologyBiomolecular Engineering
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Three-Dimensional Surface Display in Blood Pool Gated SPECT

1994

In 14 patients (4 in good health and 10 with coronary heart disease) a blood pool gated single photon emission computed tomography (SPECT) was executed. The transaxial slices of the cardiac blood pool were reconstructed. A three-dimensional surface display was employed for the analysis of the tomographic data. A fixed distance, a fixed threshold (50%), and some different planes of view were employed. The test permitted visualiza tion of the ventricular and the atrial movements in all patients. The right ventricle was clearly seen in the right anterior oblique plane of view. The aortic beating was seen. In normal patients the left ventricle, clearly seen in left anterior oblique plane, shra…

Tomography Emission-Computed Single-Photonmedicine.diagnostic_testbusiness.industryBlood poolGated SPECTCoronary DiseaseGated Blood-Pool ImagingBlood volume030204 cardiovascular system & hematologySingle-photon emission computed tomographyCoronary heart disease03 medical and health sciences0302 clinical medicinemedicine.anatomical_structureVentricleImage Processing Computer-AssistedHumansMedicineSurface geometry030212 general & internal medicineCardiology and Cardiovascular MedicinebusinessNuclear medicineArteryAngiology
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