Search results for "wt"

showing 10 items of 5424 documents

Growth of polycrystalline nickel hydroxide films from aqueous solution. Solution chemistry, deposition methods, film morphology and texture

2014

Abstract Deposition of functional ceramic films on different substrates by using soft aqueous solution processing can represent a cheap, low- energy and environmental friendly alternative to other film technologies. In this study β-Ni(OH)2 polycrystalline films were grown on polytetrafluoroethylene, NiO, glass, copper, and Y:ZrO2 substrates from Ni2 +–NH4OH aqueous solutions. A careful control of solution supersaturation was essential to induce heterogeneous nucleation on the substrate and film growth. This was realized through the gradual decomposition of the nickel amino complexes Ni(NH3)n2 + using two different methods. Thermodynamic modeling of the Ni–NH4OH–H2O system was used to provid…

SupersaturationMaterials scienceAqueous solutionNickel hydroxideInorganic chemistrySupersaturated solutionMetals and AlloysOxideNucleationSurfaces and InterfacesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsFilm morphologychemistry.chemical_compoundchemistryMaterials ChemistryHydroxideDeposition (phase transition)CrystalliteTexture (crystalline)Nucleation Growth from solutionFilm texture
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Ripening-dominated crystallization in polydisperse hard-sphere-like colloids

2009

We report on the crystal growth scenario in gravity-matched, polydisperse hard-sphere-like colloids at increasing particle concentration. In the fluid-crystal coexistence region, the crystal size as a function of time shows two separate regimes corresponding to crystal growth and crystal ripening. At higher supersaturation the crystal size grows according to the same power law through the whole experimental window of a few days: crystal growth and ripening merge together. We show that our observations cannot be explained by considering the slowing down of single-particle dynamics due to increasing volume fraction. We suggest that size fractionation occurring at the crystal-fluid interface i…

SupersaturationMaterials sciencePhysics::OpticsRipeningCrystal growthPower lawlaw.inventionColloidlawChemical physicsCondensed Matter::SuperconductivityVolume fractionCrystallizationMerge (version control)Physical Review E
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Solidification kinetics of hard-sphere colloidal suspensions

2007

We investigate the solidification dynamics of hard-sphere colloidal suspensions applying simultaneously small-angle and Bragg light scattering. These experiments allow a consistent picture of nucleation and crystal growth on the level of large-scale density fluctuations and of density fluctuations on the level of individual crystallites. We observe a temporally almost constant nucleation rate after an induction time that decreases with supersaturation. The classical expectation for the nucleation rate density as a function of supersaturation is in accordance with our data. We investigate the validity of the Wilson—Frenkel growth law for hard-sphere systems, which also fits our data satisfac…

SupersaturationOrders of magnitude (time)ChemistryChemical physicsNucleationMineralogyCrystal growthCrystalliteHard spheresLight scatteringOrder of magnitude
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Change in Newcomers' Supervisor Support and Socialization Outcomes After Organizational Entry

2009

Using a four-wave longitudinal research design and a latent growth modeling approach, we modeled change in newcomers' perceived supervisor support and socialization outcomes (role clarity, work mas...

SupervisorLatent growth modelingStrategy and ManagementSocializationJob enrichmentGeneral Business Management and Accountinglaw.inventionWork (electrical)lawOrganizational behaviorManagement of Technology and InnovationCLARITYJob satisfactionBusiness and International ManagementPsychologySocial psychologyAcademy of Management Journal
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Heterogeneous Displacement Effects of Migrant Labor Supply – Quasi-Experimental Evidence From Germany

2019

We provide estimates of the effect of migrant labor supply on resident employment. We exploit variation in the number of asylum seekers eligible to the suspension of a major hiring restriction implemented in a subset of German counties. Our difference-in-difference design allows us to provide evidence from a labor supply shock of migrants on local markets net of their additional spending at arrival that might mask labor market displacement effects. Despite this, we do not find a negative effect on employment growth of natives but only on other foreign residents. This also holds for unskilled employees. Therefore, our findings can be interpreted as the consequence of differential substitutab…

Supply shockmedia_common.quotation_subjectRefugeeImmigrationEmployment growthEconomicsDifferential (mechanical device)Demographic economicsDisplacement (psychology)Asylum seekerMigrant labormedia_commonSSRN Electronic Journal
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Control of CaCO3 Crystallization by Demixing of Monolayers

2006

In this paper we describe how to template a demixed monolayer into a spatially patterned inorganic replica. For this purpose a new amphiphilic monomer was synthesized which can be polymerized both in solution and in the monolayer of a Langmuir-Blodgett (LB) trough. Since it inhibits the crystallization of CaCO3, it can be used--in combination with stearic acid (nucleation-promotor)--to control CaCO3 crystals formed under the monolayer. Investigations of the two-component monolayer (Langmuir isotherms and AFM measurements of transferred films) show--in the biphasic region--demixing in solid analogue stearic acid domains and the liquid analogue phase of the monomer. Crystallization of CaCO3 s…

Surface PropertiesAcrylic ResinsCrystal growthSurfaces and InterfacesCondensed Matter PhysicsLipidsCalcium Carbonatelaw.inventionchemistry.chemical_compoundMonomerchemistryChemical engineeringlawPhase (matter)MonolayerSaturated fatty acidElectrochemistryOrganic chemistryGeneral Materials ScienceStearic acidCrystallizationCrystallizationStearic AcidsSpectroscopyAcrylic acidLangmuir
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The Influence of Surface Treatment on the Kinetic of Growth of Anodic Films on Magnesium in Alkaline Solution

2010

Surface Treatment Kinetic of Growth of Anodic Films Magnesium
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Epitaxial growth of molybdenum on TiO2(110)

2003

Abstract Molybdenum was deposited on blue (i.e. non-stoichiometric) TiO2(1 1 0) surface using a very low deposition rate (less than 0.05 eqML min−1). The resulting deposit was investigated by means of X-ray photoelectron diffraction (XPD), LEED and XPS. Just after deposition, the film is mainly constituted of metallic molybdenum, contains oxygen homogeneously dispersed through the whole deposit and the broad features detected in XPD scans are interpreted as a coarse epitaxy between TiO2(1 1 0) surface and the (0 0 1) face of bcc molybdenum. The orientation relationship is: Mo(1 0 0)[0 0 1]//TiO2(1 1 0)[0 0 1]. After annealing the deposit at 673 K, XPD scans become sharper and epitaxy is ach…

Surface diffusionAnnealing (metallurgy)Chemistrychemistry.chemical_elementCrystal growthSurfaces and InterfacesCondensed Matter PhysicsEpitaxySurfaces Coatings and FilmsCrystallographyX-ray photoelectron spectroscopyMolybdenumMaterials ChemistryStoichiometryMolecular beam epitaxy
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Effect of kinks and concerted diffusion mechanisms on mass transport and growth on stepped metal surfaces

1997

Abstract We study the effect of kinks and concerted atomic mechanisms on diffusion processes relevant to metal-on-metal homoepitaxy on fcc metal surfaces vicinal to the fcc (100) direction. First, we carry out extensive finite-temperature molecular dynamics simulations based on the effective medium theory to search for diffusion mechanisms that dominate the mass transport perpendicular and parallel to step edges. Then, the energetics of these processes are studied by ground state calculations. Our results show that kinks play an important role for diffusion both across and along step edges. In particular, the combined effect of kinks and concerted exchange is found to be able to remove loca…

Surface diffusionChemistryCrystal growthSurfaces and InterfacesCondensed Matter PhysicsSurfaces Coatings and FilmsMolecular dynamicsComputational chemistryChemical physicsMaterials ChemistryPerpendicularDiffusion (business)Ground stateVicinalMolecular beam epitaxySurface Science
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Cytokines and growth factors in wound drainage fluid from patients undergoing incisional hernia repair

2006

Knowing the dynamics of growth factor and cytokine secretion within the site of a surgical operation is important, as they play a crucial role in the pathophysiology of wound healing and are a target for modifying the repair response. The aim of this study was to evaluate the production of several cytokines and growth factors in the drainage wound fluid from patients undergoing incisional hernia repair: namely, interleukin (IL)-6, IL-10, IL-1alpha, IL-1 ra, interferon-gamma, vascular endothelial growth factors and basic fibroblast growth factor. Ten female patients with abdominal midline incisional hernia undergoing surgical repair were included in this study. In all cases, a closed-suction…

Surgical repairmedicine.medical_specialtybusiness.industryIncisional herniaGrowth factormedicine.medical_treatmentBasic fibroblast growth factorSurgical woundDermatologymedicine.diseaseSurgerychemistry.chemical_compoundCytokinechemistryAnesthesiamedicineSurgeryCytokine secretionWound healingbusinessWound Repair and Regeneration
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