Browsing Physics and Astronomy by Type "Article"
Now showing items 1-20 of 82
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Adsorption of surface-modified silica nanoparticles to the interface of melt poly (lactic acid) and supercritical carbon dioxide
(ACS Publications, 2015-04-28)With the purpose of fabricating polymer nanocomposite foams and preventing coalescence in foaming processes, the interfacial tension of poly (lactic acid) (PLA) -silica composites is investigated in this work. Synthesized ... -
An alternative derivation of orbital-free density functional theory
(AIP, 2019-05-28)Polymer self-consistent field theory techniques are used to derive quantum density functional theory without the use of the theorems of density functional theory. Instead, a free energy is obtained from a partition function ... -
Application of a constant hole volume Sanchez–Lacombe equation of state to mixtures relevant to polymeric foaming
(Royal Society of Chemistry, 2018)A variant of the Sanchez–Lacombe equation of state is applied to several polymers, blowing agents, and saturated mixtures of interest to the polymer foaming industry. These are low-density polyethylene– carbon dioxide and ... -
Atomic shell structure from an orbital-free-related density-functional-theory Pauli potential
(American Physical Society, 2020-07)Polymer self-consistent field theory techniques are used to find radial electron densities and total binding energies for isolated atoms. Quantum particles are modeled as Gaussian threads with ring-polymer architecture in ... -
Benchmarking a self-consistent field theory for small amphiphilic molecules
(RSC publishing, 2012-08-14)A minimalist self-consistent field theory for small amphiphilic molecules is presented. The equations for this model are less involved than those for block copolymers and are easily implemented computationally. A new ... -
Bidirectional mapping between self-consistent field theory and molecular dynamics
(AIP Publishing, 2007-10-08)A bidirectional mapping scheme that bridges particle-based and field-based descriptions for polymers is presented. Initial application is made to immiscible homopolymer blends. The forward mapping (upscaling) approach ... -
Block Copolymer-Directed Assembly of Nanoparticles: Forming Mesoscopically Ordered Hybrid Materials
(American Chemical Society, 2002)Mixtures of diblock copolymers and nanoscopic spherical particles can yield well-ordered hybrid materials, which can be used for separation processes, catalysis, and optoelectronic applications. Predicting the morphologies ... -
Calibration of a Lattice Model for High-Molecular-Weight Block Copolymer Melts
(AIP, 2019-05-06)The Morse calibration is applied to a lattice model designed for efficient simulations of two-component polymer melts of high molecular weight. The model allows multiple occupancy per site, which results in high invariant ... -
Communication: Molecular-level insights into asymmetric triblock copolymers: Network and phase development
(AIP publishing, 2014-10-01)Molecularly asymmetric triblock copolymers progressively grown from a parent diblock copolymer can be used to elucidate the phase and property transformation from diblock to network-forming triblock copolymer. In this ... -
Computationally Efficient Field-Theoretic Simulations for Block Copolymer Melts
(American Chemical Society, 2019-11-12)Field-theoretic simulations (FTS) provide fluctuation corrections to self-consistent field theory (SCFT) by simulating its field-theoretic Hamiltonian rather than applying the saddle-point approximation. Although FTS work ... -
The data processing pipeline for the Herschel1 - HIFI instrument
(Elsevier, 2019-04)The HIFI data processing pipeline was developed to systematically process diagnostic, calibration and astronomical observations taken with the HIFI science instrument as part of the Herschel mission. The HIFI pipeline ... -
Decoupling of a neutron interferometer from temperature gradients
(AIP Publishing, 2016-12-16)Neutron interferometry enables precision measurements that are typically operated within elaborate, multi-layered facilities which provide substantial shielding from environmental noise. These facilities are necessary to ... -
Effect of chain stiffness on the entropic segregation of chain ends to the surface of a polymer melt
(2019)Entropic segregation of chain ends to the surface of a monodisperse polymer melt and its effect on surface tension is examined using self-consistent field theory (SCFT). In order to assess the dependence on chain stiffness, ... -
Effect of Nanoscopic Particles on the Mesophase Structure of Diblock Copolymers
(American Chemical Society, 2002)Introduction. The fabrication of novel biomimetic photonic and electronic materials requires the manipulation of both organic and inorganic materials at the nanometer length scale. One possible means of achieving this level ... -
Effect of pressure and temperature on interfacial tension of poly lactic acid melt in supercritical carbon dioxide
(Elsevier, 2015-04-11)The interfacial tension of poly lactic acid (PLA) melt is measured in supercritical carbon dioxide (CO2) at the temperature range of 143 °C to 168 °C and CO2 pressures up to 2000 psi, using Axisymmetric Drop Shape Analysis ... -
Effect of Temperature and Pressure on Surface Tension of Polystyrene in Supercritical Carbon Dioxide
(ACS Publications, 2007-02-15)The surface tension of polymers in a supercritical fluid is one of the most important physicochemical parameters in many engineering processes, such as microcellular foaming where the surface tension between a polymer melt ... -
Effect of well-dispersed surface-modified silica nanoparticles on crystallization behavior of poly (lactic acid) under compressed carbon dioxide
(Elsevier, 2016)In this work, the crystallization behavior of poly (lactic acid) (PLA)/amine-modified silica nano- composites at different loadings of amine-modified silica (1, 2, and 8 wt %) under isothermal, non- isothermal, and isothermal ... -
Effects of molecular crowding and confinement on the spatial organization of a biopolymer
(Royal Society of Chemistry, 2016-10-25)A chain molecule can be entropically collapsed in a crowded medium in a free or confined space. Here, we present a unified view of how molecular crowding collapses a flexible polymer in three distinct spaces: free, ... -
Efficient polyyne formation by ns and fs laser-induced breakdown in ethylene and acetylene gas flow
(Elsevier, 2019-11)We studied polyyne formation by gas phase laser-induced breakdown in ethylene and acetylene gas flow using ns and fs lasers. The results show that acetylene is the most efficient target molecule for generating polyynes ... -
Elastic moduli of multiblock copolymers in the lamellar phase
(AIP Publishing, 2004-02-22)We study the linear elastic response of multiblock copolymer melts in the lamellar phase, where the molecules are composed of tethered symmetric AB diblock copolymers. We use a self-consistent field theory method, and ...