Search results for "change"

showing 10 items of 6163 documents

Dynamic Refolding of Ion-Pair Catalysts in Response to Different Anions.

2019

Four distinct folding patterns were identified in two foldamer-type urea-thiourea catalysts bearing a basic dimethylamino unit by a combination of X-ray crystallography, solution NMR studies, and computational studies (DFT). These patterns are characterized by different intramolecular hydrogen bonding schemes that arise largely from different thiourea conformers. The free base forms of the catalysts are characterized by folds where the intramolecular hydrogen bonds between the urea and the thiourea units remain intact. In contrast, the catalytically relevant salt forms of the catalyst, where the catalyst forms an ion pair with the substrate or substrate analogues, appear in two entirely dif…

inorganic chemicalsBearing (mechanical)anionitcatalysis010405 organic chemistryChemistryorganic chemicalsOrganic Chemistryfolding anion bindingIon pairs010402 general chemistrykidetiede01 natural sciences0104 chemical sciencesCatalysislaw.inventionFolding (chemistry)X-rayCrystallographyconformational changelawkatalyysisolution structuresröntgenkristallografiaThe Journal of organic chemistry
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Anion exchange membrane based on alkali doped poly(2,5-benzimidazole) for fuel cell

2012

Abstract The properties of alkali doped poly(2,5-benzimidazole) membrane with different alkali doping levels for fuel cell application are reported in this work. The alkali doping level played an important role for the ion conductivity of the membrane. The ion conductivity significantly increased with alkali doping level. The ion conductivity also increased with the temperature. The ion conductivity of the alkali doped ABPBI membrane (alkali doping level = 0.37), reached to 2.3 × 10 − 2  S cm − 1 at room temperature and 7.3 × 10 − 2  S cm − 1 at 100 °C. The water uptake of the alkali doped ABPBI membrane was increased from 9.1% to 19.2% with increasing alkali doping level at room temperatur…

inorganic chemicalsBenzimidazoleMaterials scienceIon exchangeInorganic chemistryDopingtechnology industry and agriculturesocial sciencesGeneral ChemistryConductivityCondensed Matter PhysicsAlkali metalIonchemistry.chemical_compoundMembranechemistrylipids (amino acids peptides and proteins)General Materials ScienceThermal stabilityhuman activitiesSolid State Ionics
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Ammonium adsorption, desorption and recovery by acid and alkaline treated zeolite

2021

In this study, the suitability of zeolite as a possible medium for ammonium adsorption, desorption and recovery from wastewater was investigated. Specifically, batch adsorption and desorption studies with solutions enriched in NH$_4^+$ were conducted employing zeolite to evaluate how the chemical treatment and contact time affect adsorption and desorption. Several experimental tests were carried out considering both untreated and treated zeolite. Untreated and HCl-Na treated zeolite adsorbed up to 11.8 mg NH$_4^+$ g$^{-1}$ and showed the highest efficiency in recovering NH$_4^+$ from aqueous solution. Regardless of pre-treatment, treatments with NaCl resulted in higher and faster adsorption…

inorganic chemicalsEnvironmental EngineeringSettore AGR/13 - Chimica Agraria0207 environmental engineeringFOS: Physical sciencesBioengineering02 engineering and technologyApplied Physics (physics.app-ph)010501 environmental sciencesWastewater01 natural sciencesAmmonium adsorptionWater PurificationAdsorptionDesorptionPhysics - Chemical PhysicsAmmonium CompoundsAlkaline and acid treatments Ammonium exchange capacity Ammonium kinetic adsorption Clinoptilolite Resource recovery020701 environmental engineeringZeoliteWaste Management and Disposal0105 earth and related environmental sciencesResource recoveryChemical Physics (physics.chem-ph)ClinoptiloliteAqueous solutionSettore ICAR/03 - Ingegneria Sanitaria-AmbientaleRenewable Energy Sustainability and the EnvironmentChemistryfood and beveragesGeneral MedicinePhysics - Applied Physics6. Clean waterWastewaterZeolitesAdsorptionWater Pollutants ChemicalNuclear chemistryBioresource Technology
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Trivalent cation substitution of pulverulent cobalt—iron molybdates Co1 − xFexMoO4

1998

Abstract Different mixed cobalt—iron molybdates Co1 − xFexMoO4 (0 ≤ x ≤ 1) have been prepared by means of a ceramic process. The oxidation of pulverulent samples leads to ferric molybdate Fe2(MoO4)3, spinelle Co3O4 and cobalt molybdate CoMoO4. After a strong grinding which reduces the grain size (about 0.1 μm) and induces crystallographic defects in the grains, the cobalt—iron molybdates can be partially oxidized into cation-deficient phases. This oxidation corresponds to an isostructural substitution of part of the Fe2+ and Co2+ ions by Fe3+ and Co3+ ions and the creation of cation vacancies. The concomitant presence of trivalent cations and associated cation vacancies in the lattice stabi…

inorganic chemicalsIon exchangeInorganic chemistryIron oxidechemistry.chemical_elementQuaternary compoundMolybdateCondensed Matter Physicschemistry.chemical_compoundchemistrymedicineFerricGeneral Materials ScienceIsostructuralCobaltCobalt oxidemedicine.drugMaterials Chemistry and Physics
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Change and stability of sense of coherence in adulthood: Longitudinal evidence from the Healthy Child study

2007

Abstract The main aim of this three-wave 35-year follow-up study among Finnish employees ( n  = 532) was to investigate whether Sense of Coherence (SOC) is more stable among those with high SOC compared to those with low SOC, as hypothesized by Antonovsky [Antonovsky, A. (1987). Unraveling the mystery of health: how people manage stress and stay well. San Francisco, CA, US: Jossey-Bass], using two measurement points over 13 years. The participants were first studied in adolescence in 1961–1963, after which they responded to two postal questionnaires measuring SOC, first in 1985, and again in 1998. The results of the Factor Mixture Modeling identified two groups of individuals with different…

inorganic chemicalsSocial Psychologymedia_common.quotation_subjectAdult developmentBehavior changeFactor structurebehavioral disciplines and activitiesStability (probability)Developmental psychologyWell-beingotorhinolaryngologic diseasesMixture modelingPersonalitysense organsPsychologypsychological phenomena and processesGeneral PsychologyClinical psychologySense of coherencemedia_commonJournal of Research in Personality
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Nano-sized I12L6 Molecular Capsules Based on the [N⋅⋅⋅I+⋅⋅⋅N] Halogen Bond

2017

Summary Self-assembly of pre-organized subunits with a concave overall shape is an effective strategy for the synthesis of supramolecular capsules. We report the synthesis of a cavitand-based hexameric capsule held together solely by 12 robust [N⋅⋅⋅I + ⋅⋅⋅N] halogen bonds and its characterization in solution and in the gas phase via 1 H NMR spectroscopy, diffusion-ordered nuclear magnetic resonance spectroscopy (DOSY), and electrospray ionization mass spectrometry. The [N⋅⋅⋅I + ⋅⋅⋅N] halogen-bonded hexameric capsule was efficiently synthesized from the isolobal metallosupramolecular Ag + capsule by application of the [N⋅⋅⋅Ag + ⋅⋅⋅N] → [N⋅⋅⋅I + ⋅⋅⋅N] cation-exchange reaction.

inorganic chemicalsStereochemistrycapsuleGeneral Chemical EngineeringElectrospray ionizationSupramolecular chemistrysupramolecular capsule010402 general chemistry01 natural sciencesBiochemistrysupramolecular chemistryresorcinarene cavitandMaterials ChemistryEnvironmental ChemistryHalonium ionhalonium-ion-based nanotechnologyta116silver-to-iodine cation exchangeHalogen bond010405 organic chemistryChemistryBiochemistry (medical)CavitandIsolobal principleself-assemblyGeneral ChemistryNuclear magnetic resonance spectroscopy0104 chemical sciencesCrystallographyhalonium ionProton NMRhalogen bondChem
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Electrostatic phenomena in ion exchange membranes

1971

Abstract Specific and transport properties of a cation and an anion exchange membrane in Na + and Cl - form respectively have been measured in water and dioxane water mixtures. A greater electrolyte absorption and a lesser specific conductivity and counterion transport number in solvents at higher dioxane content indicate strong electrostatic interactions between fixed groups in the membrane and counterions.

inorganic chemicalschemistry.chemical_classificationIon exchangeMechanical EngineeringGeneral Chemical EngineeringInorganic chemistryGeneral ChemistryElectrolyteConductivityElectrostaticsMembranechemistryGeneral Materials ScienceIon-exchange membranesCounterionAbsorption (chemistry)Water Science and TechnologyDesalination
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Implementing an institutional change in a regional context : A case study of telemedicine implementation and diffusion in Agder

2018

Master's thesis Information Systems IS501 - University of Agder 2018 High life expectancy, aging population and an increasing chronic diseases generates new challenges for the current global healthcare (Brouard, Bardo, Vignot, Bonnet, & Vignot, 2014). Public agencies and business corporates have shown interest inadvances technological research and innovation projects to remedy the problem. Innovating in public sector is highly challengingand results shouldn’t be taken for granted (Dacin, Goodstein, & Scott, 2002). Further, there is a lack of understanding how public innovations are created (Sørensen & Torfing, 2011). Theoretically the thesis builds on two strands of theories: institutional …

institutional changeinstitutional entrepreneurshipinnovation in public sectoreHealthIS501telemedicineVDP::Samfunnsvitenskap: 200::Statsvitenskap og organisasjonsteori: 240::Offentlig og privat administrasjon: 242institutional entrepreneurship workVDP::Teknologi: 500::Informasjons- og kommunikasjonsteknologi: 550
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Conflicting legitimations and pressures in performance measurement adoption, use and change in Finnish municipalities

2010

instituutiotmunicipalitiesaccountinghyödykkeetperformance measurementlaskentatoimimuutosmittausmenetelmätsuoritusmittauskunnatrahachangeinstitutionsnonlinearities
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Intellectual Capital – The Key for Sustainable Competitive Advantage for the SME's Sector

2015

Abstract With the adoption of the Lisbon Agenda and its major objective, namely that the EU would become the most dynamic and competitive knowledge based economy in the world, it became clear the Small and Medium Enterprises (SME's) are the especially affected by these plans, because they represent the driving force for the European economy. In this context of creating and maintaining a competitive advantage for the SME's, it is crucial for them to make good use of the intellectual capital of their employees, in an efficient and proficient manner, in order to increase their potential for innovation. The aim of this article is to show, through an original argumentation, based on the analysis…

intangible assetsbusiness.industryKnowledge economyGeneral EngineeringEnergy Engineering and Power TechnologyContext (language use)International tradeCompetitive advantageArgumentation theoryIntellectual capitalintellectual capitalOrder (exchange)SME's ;Key (cryptography)competitive advantageSmall and medium-sized enterprisesBusinessIndustrial organizationProcedia Economics and Finance
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