Search results for "thermal [radiation]"

showing 10 items of 1167 documents

Synthesis, optical, and thermal properties of glassy trityl group containing luminescent derivatives of 2-tert-butyl-6-methyl-4H-pyran-4-one

2012

In this work we present simple preparation of original trityl group containing glassy luminescent 6-styryl substituted derivatives of 2-(2-tert-butyl-4H-pyran-4-ylidene)malononitrile (DWK-1TB), 2-(2-tert-butyl-4H-pyran-4-ylidene)-2- ethyl-2-cyanoacetate (KWK-1TB), 2-(2-tert-butyl-4H-pyran-4-ylidene)-1H-indene-1,3(2H)-dione (ZWK-1TB) and 5-(2-tert-butyl-4H-pyran-4-ylidene)pyrimidine-2,4,6(1H,3H,5H)-trione (JWK-1TB). Their optical properties have been investigated. The absorption maxima of synthesized glasses is in region from 425 nm to 515 nm and emission maxima is from 470 nm to 625 nm in solution of dichloromethane. But absorption maxima of their solid films is from 425 nm to 500 nm and em…

chemistry.chemical_classificationchemistry.chemical_compoundMaterials sciencechemistryThermal decompositionPhysical chemistryThermal stabilityPolymerAbsorption (chemistry)Glass transitionLuminescenceDichloromethaneMalononitrileOrganic Photonics V
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1986

In order to graft methacrylonitrile onto preformed networks containing thermolabile azo groups, the monomer was used to swell the networks and then the temperature raised to the decomposition temperature for the azo groups. The unusually high grafting efficiencies yields (e) achieved are explained in terms of both the differences in the reactivities of the primary radicals formed and side reactions, which lead to additional grafting sites. As an aid to understand the dependence of monomer conversion on that of the initiator a kinetic model is discussed, which involves the consideration of the polymerization taking place both in the homogeneous phase and within the polymer pearls, which can …

chemistry.chemical_classificationchemistry.chemical_compoundMonomerchemistryPolymerizationMethacrylonitrilePolymer chemistryThermal decompositionCopolymerGeneral Materials SciencePolymerThermolabileGraftingAngewandte Makromolekulare Chemie
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Thermal and optical properties of 4H-pyran-4-ylidene fragment and bis-styryl and triphenyl groups containing derivatives

2014

Small D-π-A type organic molecules with incorporated 4H-pyan-4-ylidene (pyranylidene) fragment in their structures show potential in organic photonics - such as materials for organic light emitting diode application studies and organic solid state lasers. Additional incorporation of bulky triphenyl- groups in their structures gives them the ability to form thin amorphous solid films from volatile non-polar organic solvents. Unfortunately, there is still no clear relation between compound organic structures and their thermal and optical properties. In order to investigate the above mentioned regularities we have synthesized a series of tripheyl- group containing derivates of 2,6-bis-styryl-4…

chemistry.chemical_classificationchemistry.chemical_compoundPhotoluminescenceMaterials sciencechemistryOrganic photonicsThermal decompositionSubstituentElectron acceptorGlass transitionPhotochemistryDichloromethaneAmorphous solidSPIE Proceedings
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Binding abilities of new cyclodextrin-cucurbituril supramolecular hosts

2015

Various combined techniques (UV–vis spectrophotometry, isothermal titration calorimetry, thermogravimetry, ESI-MS mass spectrometry, polarimetry and 1H NMR spectroscopy) were used in order to study the interaction between a new combined supramolecular host, namely a bow-tie-structured cyclodextrin–cucurbituril association solely held by non-covalent interactions, and a suitably selected guest, namely the N-(p-nitrophenyl)-1,8-diaminooctane hydrochloride. In particular, the use of different techniques highlighted the peculiar features of the possible host–guest supramolecular interactions under different concentration conditions.

chemistry.chemical_classificationcucubiturilCyclodextrinsmedicine.diagnostic_testCyclodextrinHydrochloridecucurbiturilsSupramolecular chemistryIsothermal titration calorimetryGeneral ChemistrySettore CHIM/06 - Chimica OrganicaMass spectrometrycucurbiturilThermogravimetryCrystallographychemistry.chemical_compoundcyclodextrinchemistryComputational chemistryCucurbiturilSpectrophotometrymedicinecucurbiturils; Cyclodextrins; supramolecular co-polymerssupramolecular co-polymerscyclodextrins; cucurbiturils; supramolecular co-polymers
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Recognition of Viologen Derivatives in Water by N-Alkyl Ammonium Resorcinarene Chlorides

2017

Three water-soluble N-alkyl ammonium resorcinarene chlorides decorated with terminal hydroxyl groups at the lower rims were synthesized and characterized. The receptors were decorated at the upper rim with either terminal hydroxyl, rigid cyclohexyl, or flexible benzyl groups. The binding affinities of these receptors toward three viologen derivatives, two of which possess an acetylmethyl group attached to one of the pyridine nitrogens, in water were investigated via 1H NMR spectroscopy, fluorescence spectroscopy, and isothermal titration calorimetry (ITC). ITC quantification of the binding process gave association constants of up to 103 M–1. Analyses reveal a spontaneous binding process whi…

chemistry.chemical_classificationta114010405 organic chemistryOrganic ChemistryEnthalpyIsothermal titration calorimetryViologenResorcinarene010402 general chemistry01 natural sciencesviologen derivativesFluorescence spectroscopy0104 chemical scienceschemistry.chemical_compoundN-alkyl ammonium resorcinarene chlorideschemistryPyridinePolymer chemistrymedicineOrganic chemistryAmmoniumta116Alkylmedicine.drugJOURNAL OF ORGANIC CHEMISTRY
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Synthesis and thermal decomposition studies of homo- and heteroleptic tin(iv) thiolates and dithiocarbamates: molecular precursors for tin sulfides

2002

The syntheses and X-ray structures of novel heteroleptic thiolate/dithiocarbamate derivatives (Et2NCS2)2(RS)2Sn (R = Cy, CH2CF3) have been examined and their thermal decompositions compared with those of selected tin(II) and tin(IV) dithiocarbamates. The heteroleptic species decompose to SnS by initial elimination of RSSR to afford (Et2NCS2)2Sn and subsequent loss of [Et2NC(S)]2S. In contrast, (Et2NCS2)4Sn decomposes via [(Et2NCS2)2SnS]2, whose structure has been determined, and finally to SnS2 by sequential elimination of [Et2NC(S)]2S. The two families of compounds, (R2NCS2)4Sn and (Et2NCS2)2(RS)2Sn, thus provide single-source materials for bulk SnS2 and SnS, respectively, by virtue of the…

chemistry.chemical_classificationtin thiolatesMössbauer spectroscopyChemistryInorganic chemistryThermal decompositionSolid-statechemistry.chemical_elementGeneral ChemistryCrystal structureChemical vapor depositionMedicinal chemistryDecompositionchemical vapor depositionSettore CHIM/03 - Chimica Generale E InorganicaTinDithiocarbamateX-ray crystallographyJournal of the Chemical Society, Dalton Transactions
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Differential calorimetric enthalpies of adsorption ofp-xylene andm-xylene on y faujasites at 25°C

1997

The differential enthalpies of adsorption ofp-xylene andm-xylene on NaY, KY and BaY zeolites were measured by isothermal calorimetry coupled with isothermal volumetry at 25‡C. Whatever the zeolite, the enthalpies of adsorption ofp-xylene andm-xylene at low filling were of the same order of magnitude. They did not show significantly the effect of the dipolar moment ofm-xylene. Their absolute values varied in the sequence

chemistry.chemical_compoundAdsorptionChromatographychemistryEnthalpyXylenePhysical chemistryIsothermal titration calorimetryCalorimetrym-Xylenep-XyleneIsothermal processJournal of Thermal Analysis
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Evidence for the formation of 1,3- and 1,4-dehydrobenzenes in the thermal decomposition of diaryliodonium-carboxylates

1986

Abstract Abstract: Generation of m- and p-benzynes in decomposition of diaryliodonium- 3- and 4-carboxylates is demonstrated by three-phase method.

chemistry.chemical_compoundBetaineChemistryOrganic ChemistryDrug DiscoveryThermal decompositionReaction intermediatePhotochemistryBiochemistryAryneDecompositionPyrolysisTetrahedron Letters
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Bulk pre-reactional transformations preceding the thermal decomposition of calcium hydroxide into oxide

1990

The present paper is an extended abstract which should be considered as an introduction to the papers already published by us on this new topic. An extended synthesis of these papers was given in the lecture. The original information introduced here is the figure. It is a PH2O vs. T diagram which gives the pre-reactional domain between the stability domains of calcium hydroxide and calcium oxide. Chemical reactions are proposed as an interpretation of the observed pre-reactional transformations.

chemistry.chemical_compoundCalcium hydroxidechemistryInorganic chemistryThermal decompositionDiagramGeneral EngineeringOxideThermodynamicsCalcium oxideChemical reactionReactivity of Solids
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Studies on the synthesis of heterocyclic compounds. Part IV. Further investigation of the pschorr reaction with some pyrazole derivatives

1980

Thermal decomposition of the diazonium sulfate derived from N-methyl-(1-phenyl-3-methylpyrazol-5-yl)-2-aminobenzamide afforded products formulated as 1-phenyl-3-methyl[2]benzopyrano[4,3-c]pyrazol-5-one (yield 10%), 1,4-dimethyl-3-phenylpyrazolo[3,4-c]isoquinolin-5-one (yield 10%), N-methyl-(1-phenyl-3-methylpyrazol-5-yl)-2-hydroxybenzamide (yield 8%) and 4′-hydroxy-2,3′-dimethyl-1′-phenylspiro[isoindoline-1,5′-[2]-pyrazolin]-3-one (yield 20%). Decomposition of the diazonium sulfate derived from N-methyl-(1,3-diphenylpyrazol-5-yl)-2-aminobenzamide gave products formulated as 7,9-dimethyldibenzo[e,g]pyrazolo[1,5-a][1,3]-diazocin-10-(9H)one (yield 8%), 4-methyl-1,3-diphenylpyrazolo[3,4-c]isoqu…

chemistry.chemical_compoundChemistryYield (chemistry)Organic ChemistryThermal decompositionOrganic chemistryPyrazoleRing (chemistry)Spectral dataMedicinal chemistryDecompositionJournal of Heterocyclic Chemistry
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