Search results for "DF"

showing 10 items of 1699 documents

Use of an enzyme-assisted method to improve protein extraction from olive leaves.

2013

The improvement of protein extraction from olive leaves using an enzyme-assisted protocol has been investigated. Using a cellulase enzyme (Celluclast® 1.5L), different parameters that affect the extraction process, such as the influence and amount of organic solvent, enzyme amount, pH and extraction temperature and time, were optimised. The influence of these factors was examined using the standard Bradford assay and the extracted proteins were characterised by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The optimum extraction parameters were: 30% acetonitrile, 5% (v/v) Celluclast® 1.5L at pH 5.0 and 55°C for 15min. Under these conditions, several protein extracts…

ChromatographybiologyChemistryPlant ExtractsSodiumExtraction (chemistry)Temperaturechemistry.chemical_elementGeneral MedicineCellulaseChemical FractionationAnalytical ChemistrySolventPlant LeavesElectrophoresisCellulaseOleaProtein purificationbiology.proteinElectrophoresis Polyacrylamide GelPolyacrylamide gel electrophoresisBradford protein assayFood SciencePlant ProteinsFood chemistry
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Raons essencials i creença

2003

In this paper I defend that what I call modes of denotation are part of one¿s belief content, even if they are not part of the proposition expressed by the sentence one believes to be true. Two people, who believe of the same sentence (not ambiguous) that it is true can have different belief contents that they express by means of this same sentence.

Ciencias básicas y experimentalesTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESUNESCO::FILOSOFÍA:FILOSOFÍA [UNESCO]HumanidadesVeritat i mentidaHª y Fª de la CienciaFilosofía. Etica
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Supramolecular Chirogenesis in Bis-Porphyrin: Crystallographic Structure and CD Spectra for a Complex with a Chiral Guanidine Derivative

2021

The complexation of (3aR,7aR)-N-(3,5-bis(trifluoromethyl)phenyl)octahydro-2H-benzo[d]imidazol-2-imine (BTI), as a guest, to ethane-bridged bis(zinc octaethylporphyrin), bis(ZnOEP), as a host, has been studied by means of ultraviolet-visible (UV-Vis) and circular dichroism (CD) absorption spectroscopies, single crystal X-ray diffraction, and computational simulation. The formation of 1:2 host-guest complex was established by X-ray diffraction and UV-Vis titration studies. Two guest BTI molecules are located at the opposite sides of two porphyrin subunits of bis(ZnOEP) host, which is resting in the anti-conformation. The complexation of BTI molecules proceed via coordination of the imine nitr…

Circular dichroismPhysics and Astronomy (miscellaneous)General MathematicsImineSupramolecular chemistrychiralityCrystal structurehost-guest binding010402 general chemistryguanidine01 natural sciencesDFTsupramolecular chemistrykemialliset sidoksetchemistry.chemical_compoundsupramolekulaarinen kemiaComputer Science (miscellaneous)Molecule[CHIM]Chemical SciencesGuanidine010405 organic chemistrylcsh:Mathematicstiheysfunktionaaliteoriahost–guest bindinglcsh:QA1-939Porphyrin0104 chemical sciencescircular dichroismCrystallographyTD-DFT simulationchemistryChemistry (miscellaneous)Chirality (chemistry)porphyrin
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Context-free Languages

1988

In this chapter we shall define a class of rewriting systems called context-free grammars. The left-hand side of a rule in a context-free grammar consists of a single symbol, so that symbols are rewritten “context-freely”. Context-free grammars are of central importance to us because they define the class of context-free languages, the parsing of which is the subject of this book. In this chapter we shall consider some structural properties of context-free grammars which are of importance in parsing. Also, a basic method for recognizing context-free languages will be given.

Class (computer programming)ParsingGrammarComputer scienceProgramming languagemedia_common.quotation_subjectContext-free languagecomputer.software_genreTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESRule-based machine translationSymbol (programming)Subject (grammar)Rewritingcomputermedia_common
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A lower bound for the Bloch radius of 𝐾-quasiregular mappings

2004

We give a quantitative proof to Eremenko’s theorem (2000), which extends Bloch’s classical theorem to the class of n n -dimensional K K -quasiregular mappings.

Class (set theory)Pure mathematicsTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESApplied MathematicsGeneral MathematicsMathematicsofComputing_GENERALGeometryRadiusClassical theoremGeneralLiterature_REFERENCE(e.g.dictionariesencyclopediasglossaries)Upper and lower boundsMathematicsProceedings of the American Mathematical Society
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Indefinitely stable iron(IV) cage complexes formed in water by air oxidation

2017

In nature, iron, the fourth most abundant element of the Earth's crust, occurs in its stable forms either as the native metal or in its compounds in the +2 or +3 (low-valent) oxidation states. High-valent iron (+4, +5, +6) compounds are not formed spontaneously at ambient conditions, and the ones obtained synthetically appear to be unstable in polar organic solvents, especially aqueous solutions, and this is what limits their studies and use. Here we describe unprecedented iron(IV) hexahydrazide clathrochelate complexes that are assembled in alkaline aqueous media from iron(III) salts, oxalodihydrazide and formaldehyde in the course of a metal-templated reaction accompanied by air oxidation…

ClathrochelateScienceInorganic chemistryFormaldehydeSolid-stateGeneral Physics and Astronomy010402 general chemistryDFT01 natural sciencesArticleGeneral Biochemistry Genetics and Molecular BiologyInorganic Chemistrychemistry.chemical_compoundhigh-valent ironNative metalOorganisk kemiMultidisciplinaryAqueous solution010405 organic chemistryQGeneral ChemistryDecompositionCoordination chemistry3. Good health0104 chemical scienceschemistryCageEarth (classical element)Nature Communications
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A computational and experimental investigation of halloysite silicic surface modifications after alkaline treatment

2023

Density functional theory calculations were performed in order to investigate the formation of silanol groups on the outer surface of halloysite nanotubes, as possible products of the reactions with water in alkaline environments. The results, discussed in terms of energy release and structural properties of the modified surface, suggest that the formation of various kinds of silanol group constellations, and even the extraction of orthosilicic acid, are highly exothermic reaction in the presence of hydroxide ions. Thermogravimetric analysis, FT-IR, XRD and X-ray fluorescence spectrometry performed on halloysite treated at high pH conditions indicate that the adsorption of water on the oute…

Clay materialsGeochemistry and PetrologySpiral nanotubesGeologyFunctionalizationDFTApplied Clay Science
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Climate Classification and Division of China

1988

As far as a climate classification and division is concerned, China represents a great complexity and diversity due to the country’s vast territory and extremely complex landforms. In detail, three major climate-governing factors must be taken into consideration for the climate of China as such and for its division over space: (1) the geographical latitude, (2) the elevation above sea level and (3) the distance from the Pacific Ocean. Of particular importance for a climate regionalization of China is the country’s location on the southeastern corner of the Eurasian continent against the Pacific Ocean, which means that the nature of the surrounding regions varies from open oceans to compact …

Climate classificationgeographygeography.geographical_feature_categoryLandformClimatologyElevationContext (language use)Aridity indexPhysical geographyDivision (mathematics)ChinaSea level
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Species of Oswaldella Stechow, 1919 (Cnidaria, Hydrozoa) from recent antarctic expeditions with R.V. 'Polarstern', with the description of eight new …

1997

Twelve species of the genusOswaldellaStechow have been studied, eight of which are new to science [Oswaldella delicatasp. nov.,O. encarnaesp. nov.,O. garciacarrascosaisp. nov.,O. gracilissp. nov.,O. grandissp. nov.,O. incognitasp. nov.,O. obscurasp. nov.andO. rigidasp. nov.], originating from the Weddell Sea and collected by several antarctic expeditions with R.V.Polarstern. Each is described and figured, its systematic position is considered and current data concerning its autecology and geographical distribution are given. Finally, a comparative table is presented including the principal features of all known species of the genus.

CnidariaSystematicsPaleontologybiologyGenusOswaldellaTable (landform)Animal Science and Zoologybiology.organism_classificationEcology Evolution Behavior and SystematicsHydrozoa
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Effects of a ludic-motor program on motor development and early literacy skills in preschool children

2017

There is insufficient evidence in the literature about many correlations between motor and cognitive skills in 3-5 year old children [1]. The aim of this study was to explore the relationship between the development of the gross motor skills and the prerequisites of reading/writing following a ludic-motor program (LMP) in pre-school children. This study has involved 189 children (age: 4.62 ± 0.97 years; height: 107.83 ± 7.82 cm, body weight: 19.84 ± 4.95 kg) attending 8 kindergartens in Palermo. The children were randomly divided in a control group (C, n= 29), a 1-intervention group (I-1, n= 120) and a 2-intervention group (I-2, n= 40). I-1 and I-2 respectively performed 4 and 10 hours/week…

CognitionSettore M-EDF/02 - Metodi E Didattiche Delle Attivita' SportiveMotor programeducationMotor skillsChildrenSettore M-EDF/01 - Metodi E Didattiche Delle Attivita' MotorieChildren; motor skills; cognition; motor program
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