Search results for "MR"

showing 10 items of 3001 documents

Assessing the influence of different biochar fractions on soil structure and soil water retention: laboratory investigation on a Sicilian soil

2012

biochar soil water retention NMR relaxometrySettore AGR/13 - Chimica AgrariaSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-Forestali
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Excitation Energy Transfer in Isolated Chlorosomes from Chlorobaculum tepidum and Prosthecochloris aestuarii

2012

Excitation energy transfer in chlorosomes from photosynthetic green sulfur bacteria, Chlorobaculum (Cba.) tepidum and Prosthecochloris (Pst.) aestuarii, have been studied at room temperature by time-resolved femtosecond transient absorption spectroscopy. Bleach rise times from 117 to 270 fs resolved for both chlorosomes reflect extremely efficient intrachlorosomal energy transfer. Bleach relaxation times, from 1 to 3 ps and 25 to 35 ps, probed at 758 nm were tentatively assigned to intrachlorosomal energy transfer based on amplitude changes of the global fits and model calculations. The anisotropy decay constant of about 1 ps resolved at 807 nm probe wavelength for the chlorosomes from Chlo…

biologyChemistryChloroflexus aurantiacusRelaxation (NMR)ChlorosomeGeneral Medicinebiology.organism_classificationPhotochemistryBiochemistryChemical physicsGreen sulfur bacteriaUltrafast laser spectroscopyFemtosecondPhysical and Theoretical ChemistrySpectroscopyExcitationPhotochemistry and Photobiology
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Chapter 6 Contribution of NMR Spectroscopy to Flavour Release and Perception

2008

Abstract The control of flavouring of a food product as well as the flavour perception during consumption is a great challenge for improving food quality. However, the various ingredient composition and the different textural properties of foods can significantly affect the release of aroma compounds or sapid molecules. It is thus of major importance to determine physicochemical factors that govern diffusion and binding phenomena of these small solutes in food products. In this way, NMR spectroscopy is an efficient tool to characterize these mechanisms at a molecular scale. Diffusion rates of small solutes in aqueous, viscous and gel solutions can be extracted from relaxation or diffusion N…

biologyChemistryDiffusion010401 analytical chemistryFlavourRelaxation (NMR)Analytical chemistryfood and beverages04 agricultural and veterinary sciencesNuclear magnetic resonance spectroscopybiology.organism_classification040401 food science01 natural sciences0104 chemical scienceschemistry.chemical_compound0404 agricultural biotechnologyComputational chemistryAroma compoundMoleculeSpectroscopyAroma
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1H 2D-NMR characterization of Ni(II)-substituted azurin fromPseudomonas aeruginosa

1993

1 H two-dimemional NMR experiments on nickel(II)-substituted azurin have been succesfully applied. Despite the short relaxation time of the hyperfine-shifted resonances, the combined use of NOESY and COSY spectra allowed the alignment of 15 resonances belonging to the metal-coordinated residues Gly-45, His-46, His-117 and Met-121. Even in the case of the two broad and furthest downfield resonances, the NOESY spectra were successful in assigning these signals to the β-CH 2 protons of Cys-112. The protons of the non-coordinated residues Met-13, Phe-15 and Trp-48 were also assigned via NOESY, COSY and TOCSY experiments

biologyChemistryStereochemistryAzurinachemistry.chemical_elementGeneral ChemistryNuclear magnetic resonance spectroscopybiology.organism_classificationSpectral lineCharacterization (materials science)NickelProton NMRGeneral Materials ScienceAzurinTwo-dimensional nuclear magnetic resonance spectroscopyMagnetic Resonance in Chemistry
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One-step synthesis of resorcarene dimers composed of two tetra-benzoxazine units

1998

Abstract The condensation of resorcarene 1 with ethylenediamine and an excess of formaldehyde gives, under high dilution conditions, in up to 15% yield the octa-benzoxazine dimer 2 in which two molecules of 1 are connected by four bridges. The structure of 2 has been confirmed by 1 H NMR spectra and MALDI-TOF mass spectra and by hydrolysis of the oxazine rings yielding the secondary amine 3 .

biologyDimerOrganic ChemistryEthylenediamineResorcinarenebiology.organism_classificationBiochemistrychemistry.chemical_compoundchemistryDrug DiscoveryPolymer chemistryMass spectrumProton NMROrganic chemistryTetraMoleculeAmine gas treatingTetrahedron Letters
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Types of names of Orobanche taxa described from North Africa

2013

In the framework of the revision of the genus Orobanche (including Phelipaea) in the Mediterranean area, the original material for 31 names of new taxa described from North Africa by Ball, Battandier, Forsska°l, Maire (partly with Emberger and Jahandiez), Persoon, Poiret and Pomel has been analysed. Typification is discussed, and where necessary types are designated. Accepted names and synonyms of the recognized taxa are given. Three species are illustrated, and one new combination (O. inexspectata) is proposed.

biologyEcologySettore BIO/02 - Botanica SistematicaNorth africaPlant Sciencebiology.organism_classificationOrobancheTaxonOrobanchaceaeBotanyTypificationMediterranean areaNomenclature typification Mediterranean flora Orobanchaceae broomrapeNomenclatureEcology Evolution Behavior and Systematics
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Orobanche apuana (Orobanchaceae) a new species endemic to Italy

2015

Orobanche apuana , a new species belonging to Orobanche sect. Orobanche , is described and illustrated from the Apuan Alps, Central Italy. Its relationships with the other species of the group of O. caryophyllacea ( O . grex Galeatae ) and with other Orobanche that parasitize Santolina species are examined. The names Boulardia latisquama , Orobanche lutea and O. teucrii are here lectotypified.

biologySettore BIO/02 - Botanica SistematicaGrex (horticulture)Plant Sciencebiology.organism_classificationOrobanchebroomrape Santolina pinnata Mediterranean floraOrobanchaceaeSantolina pinnataOrobanche luteaSantolinaBotanyBoulardia latisquamaEcology Evolution Behavior and SystematicsPhytotaxa
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Typification of the name orobanche ebuli huter & rigo (orobanchaceae) and its taxonomic implications

2018

The present contribution is part of the ongoing work aimed at researching and identifying the original material on which the names of Orobanche Linnaeus (1753: 632) described for Europe and the Mediterranean are based (Domina et al. 2005, Domina & Stepanek 2009, Domina et al. 2013, Carlón et al. 2015). It falls within the researches promoted by the Italian Botanical Society aimed at recognizing and typifying all the taxa described from Italy and their loci classici, in order to increase their systematic knowledge and promote further studies (Domina et al. 2012, Peruzzi et al. 2015, Brundu et al. 2017). Orobanche ebuli Huter & Rigo (1907: 354), is an Italian endemic (Peruzzi et al. 2…

biologySettore BIO/02 - Botanica SistematicaPlant Sciencebiology.organism_classificationOrobancheTaxonOrobanchaceaeSettore BIO/03 - Botanica Ambientale E ApplicataTypificationTaxonomy (biology)Nomenclature Taxonomy Broomrape Flora of Italy EndemismEudicotsEndemismHumanitiesNomenclatureEcology Evolution Behavior and Systematics
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Revision of the structure of torrentin

1989

Abstract The structure of the eudesmanolide torrentin from Artemisia herba-alba subs valentine has been revised on the basis of high-field 1 H NMR spectroscopy and chemical correlations.

biologyStereochemistryArtemisia herba-albaChemistryProton NMRPlant ScienceGeneral MedicineHorticulturebiology.organism_classificationMolecular BiologyBiochemistryPhytochemistry
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Caryophyllene derivatives from Pulicaria dysenterica

1992

Abstract A reinvestigation of the aerial parts of Pulicaria dysenterica has allowed the isolation of six new caryophyllene derivatives and 12 known ones. 13 C NMR data of all these derivatives are reported.

biologyStereochemistryCaryophyllenePulicaria dysentericaPlant ScienceGeneral MedicineHorticultureCarbon-13 NMRSesquiterpenebiology.organism_classificationBiochemistrychemistry.chemical_compoundchemistryInuleaeOrganic chemistryMolecular BiologyPhytochemistry
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