Bernhard A. Wolf2002-12-14arXiv
In part I of this contribution we have reported how the Flory-Huggins interaction parameter chi can be modeled as a function of chain length within the composition range of pair interaction between the macromolecules by means of the three parameters alpha, zeta and lambda. This contribution presents the extension of t…
Materials ScienceSoft Condensed Matter
Maria Bercea、Maria Cazacu、Bernhard A. Wolf2002-12-14arXiv
This is the first of two parts investigating the Flory-Huggins interaction parameter chi as a function of composition and chain length. Part I encompasses experimental and theoretical work. The former comprises the synthesis of poly(dimethylsiloxane)s with different molar mass and the measurements of their second osmo…
Materials ScienceSoft Condensed Matter
Pil Kwon Jun、Heung Bin Lim2002-12-13Journal of Analytical Atomic Spectrometry
An analytical method of determining Cu contamination on Si wafer surfaces was studied. In order to make contaminated reference wafers, two forced contamination methods, i.e., particle deposition and spin coating, were used. For the former, mono-dispersed Cu particles in the submicron range were deposited on the Si waf…
X-ray Spectroscopy and Fluorescence AnalysisLaser-induced spectroscopy and plasmaElectron and X-Ray Spectroscopy Techniques
Veaceslav Ursachi、F J Manj n、K. Syassen 等 6 位作者2002-12-13Journal of Physics Condensed Matter
Porous gallium phosphide (GaP) with a honeycomb-like morphology and a skeleton relative volume concentration c = 0.7 was investigated by Raman spectroscopy under pressure up to 10 GPa at T = 5 K. The porous samples were prepared by electrochemical etching. The transverse optical (TO) and longitudinal optical (LO) mode…
Quantum Dots Synthesis And PropertiesHigh-pressure geophysics and materialsSilicon Nanostructures and Photoluminescence
Hajime Tanaka、Takehito Koyama、Takeaki Araki2002-12-13Journal of Physics Condensed Matter
Viscoelastic phase separation is a new type of phase separation, which may be universal in any dynamically asymmetric mixture composed of slow and fast components. In such a dynamically asymmetric mixture, phase separation generally leads to the formation of a long-lived ‘interaction network’ (transient gel) of the sl…
Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesBlock Copolymer Self-Assembly
Satoshi Takesono、Masayuki Onodera、Masanori Yoshida 等 5 位作者2002-12-13Journal of Chemical Technology & Biotechnology
Abstract In a stirred‐tank reactor (STR), a comparison of the performance of mechanical foam‐breakers: a six‐blade turbine (F‐B), a six‐blade vaned disk (V‐D), a two‐blade paddle (T‐P), a conical rotor (C‐R), a fluid‐impact dispersion apparatus (FIDA) and a rotating disk mechanical foam‐breaker (MFRD) was carried out…
Fluid Dynamics and MixingMinerals Flotation and Separation TechniquesPickering emulsions and particle stabilization
Garegin A. Papoian、William F. DeGrado、Michael L. Klein2002-12-13Journal of the American Chemical Society
We present three theoretical models of various degree of completeness to explore the chemical phase space available to the Glu4His2Zn2 cofactor found in the four-helix bundle of de novo designed metalloprotein Duo Ferro 1. We have found that the planewave DFT geometry optimization of 94-atom Model I, which contains bo…
Metal complexes synthesis and propertiesCorrosion Behavior and InhibitionMetal-Catalyzed Oxygenation Mechanisms
Wilson C. K. Poon、Khoa N. Pham、Stefan U. Egelhaaf 等 4 位作者2002-12-13Journal of Physics Condensed Matter
We study glass formation in hard spheres with short-range attraction. The system consists of nearly-hard-sphere polymethylmethacrylate particles and non-adsorbing random-coil polystyrene which induced a depletion attraction between the particles. The experiments reveal a re-entrant glass transition and two qualitative…
Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesTheoretical and Computational Physics
R. Memmer、Olivier Fliegans2002-12-13Physical Chemistry Chemical Physics
The orientational properties of liquid crystals in twisted nematic (TN) and supertwisted nematic (STN) cells were studied by Monte Carlo (MC) simulation depending on the strength of an external field. The liquid crystals sandwiched between planar surfaces were described by three-dimensional lattice systems of dimensio…
Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesPhase-change materials and chalcogenides
Joaquín Silvestre‐Albero、Antonio Sepúlveda‐Escribano、F. Rodrı́guez-Reinoso 等 4 位作者2002-12-13Physical Chemistry Chemical Physics
Infrared spectra of CO alone and CO followed by the introduction of 2-butenal (crotonaldehyde) have been recorded for Pt/CeO2–SiO2 and Zn doped Pt/CeO2–SiO2 catalysts which had been pre-reduced at 473, 623 and 773 K. Samples treated at the highest reduction temperature showed the greatest selectivity toward the unsatu…
Catalytic Processes in Materials ScienceCatalysts for Methane ReformingCatalysis and Oxidation Reactions
Kris Driesen、S. Fourier、Christiane Görller‐Walrand 等 4 位作者2002-12-13Physical Chemistry Chemical Physics
Lanthanide complexes of 1,10-phenanthroline (phen), 2,2′-bipyridine (bipyridyl, bpy) and dipicolinate (dpa), together with uncomplexed lanthanide ions (Ln = Nd, Sm, Dy, Ho, Er) were doped into silica–polyethylene glycol (SiO2–PEG) inorganic–organic hybrid materials. The samples were prepared via a sol–gel process. The…
Mesoporous Materials and CatalysisLanthanide and Transition Metal ComplexesPolyoxometalates: Synthesis and Applications
Rubén López‐Fonseca、Jose Ignacio Gutiérrez-Ortiz、M.A. Gutiérrez–Ortiz 等 4 位作者2002-12-13Journal of Chemical Technology & Biotechnology
Abstract Several H‐zeolites (H‐Y, H‐ZSM‐5 and H‐MOR) were investigated for the catalytic combustion of chlorinated ethylenes, namely 1,1‐dichloroethylene and trichloroethylene. Conversion was inversely related to the chlorine content of the feed molecule. H‐ZSM‐5 zeolite was the most active catalyst in 1,1‐dichloroeth…
Catalytic Processes in Materials ScienceZeolite Catalysis and SynthesisCatalysis and Oxidation Reactions
Roland Roth2002-12-13Journal of Physics Condensed Matter
We calculate the depletion potential between two hard spheres of radii R s and that between one hard sphere and a planar hard wall in a sea of hard rigid spherocylindrical rods of length L and radius R r . Unlike earlier studies our approach takes into account the true geometry of the problem and gives, to first order…
Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesThermodynamic properties of mixtures
Jure Dobnikar、Yong Chen、Roland Rzehak 等 4 位作者2002-12-13Journal of Physics Condensed Matter
At low ionic strength the interaction between any two charged colloids in a concentrated charge-stabilized suspension is strongly influenced by the charge distributions of other colloids in the neighbourhood of the two interacting colloids. When such many-body interactions become important, a colloidal suspension can…
Material Dynamics and PropertiesSpectroscopy and Quantum Chemical StudiesElectrostatics and Colloid Interactions
Dirk G. A. L. Aarts、Julia Wiel、H. N. W. Lekkerkerker2002-12-13Journal of Physics Condensed Matter
We report measurements on gas–liquid phase-separating colloid–polymer mixtures. A horizontally placed optical microscope with long-working-distance objectives enables us to see effects of gravity on phase separation kinetics and hence see the complete phase separation from beginning to end. Furthermore, the static pro…
Phase Equilibria and ThermodynamicsPickering emulsions and particle stabilizationParticle Dynamics in Fluid Flows
Stephen Cobbe、Stephen Connolly、Declan Ryan 等 6 位作者2002-12-13The Journal of Physical Chemistry B
The controlled assembly in solution of gold nanocrystals modified by attachment of complementary protein−DNA conjugates is described. The size of the aggregates formed can be controlled by the addition of single-stranded DNA, which quickly terminates the assembly process. The rate of formation of the aggregates can al…
Gold and Silver Nanoparticles Synthesis and ApplicationsQuantum Dots Synthesis And PropertiesNanocluster Synthesis and Applications
Varong Pavarajarn、Shoichi Kimura2002-12-13Industrial & Engineering Chemistry Research
The role of hydrogen in the direct nitridation of silicon was studied in conjunction with the role of oxygen contained in both the gas and solid phases at temperatures ranging from 1150 to 1350 °C in nitrogen containing hydrogen from 0 to 10 vol %. Hydrogen prevented a protective layer, being composed of silicon dioxi…
Advanced ceramic materials synthesisSemiconductor materials and devicesMXene and MAX Phase Materials
V. V. Laguta、M. D. Glinchuk、R. O. Kuzian 等 8 位作者2002-12-13Journal of Physics Condensed Matter
We report the results of an electron spin resonance study of Ti 3+ centres in SrTiO 3 single crystals. The Ti 3+ centres are created in perturbed regular Ti 4+ sites by trapping a photoelectron from the conduction band after ultraviolet irradiation of the sample at low temperature ( T < 180 K). The centres are stable…
Advancements in Solid Oxide Fuel CellsMagnetic and transport properties of perovskites and related materialsElectronic and Structural Properties of Oxides
Holger Stark、Dieter Ventzki、Michael Reichert2002-12-13Journal of Physics Condensed Matter
We review the novel features of the Stokes drag of a spherical particle dispersed in a nematic solvent. It is anisotropic, couples to rotations of the particle, and exhibits strong non-linearities.
Liquid Crystal Research AdvancementsOrbital Angular Momentum in OpticsSurfactants and Colloidal Systems
Alvaro Augusto O. Magalhães、Bernard Tribollet、O.R. Mattos 等 5 位作者2002-12-13Journal of The Electrochemical Society
The formation of chromate conversion coatings on zinc was studied by chronopotentiometric, electrochemical, and electrohydrodynamic impedances, and interfacial pH measurements. The electrochemical experiments were performed with a rotating disk electrode of pure zinc, and the pH measurements were obtained with a zinc…
Corrosion Behavior and InhibitionHydrogen embrittlement and corrosion behaviors in metalsElectrodeposition and Electroless Coatings