Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
The electron-irradiation-induced crystallization of amorphous Al2O3 (a-Al2O3) was investigated by in-situ transmission electron microscopy under the wide electron-energy region of 25–300 keV. The formation of γ-Al2O3 nanocrystallites was induced by irradiating the a-Al2O3 thin film along with the formation of nanovoid…
In this paper we present a time-domain time-dependent density functional theory (TDDFT) approach to calculate frequency-dependent polarizability and hyperpolarizabilities. In this approach, the electronic degrees of freedom are propagated within the density matrix based TDDFT framework using the efficient modified mid…
The energy barriers of lithium-ion mobility in a V 2 O 5 cathode are calculated using the nudged elastic band method. The low activation energy of the hopping pathway along the 〈0 1 0〉 direction (paralleling with the b -axis, the shortest lattice parameter) indicates that V 2 O 5 has a one-dimensional diffusion patter…
The lack of a bandgap makes bulk graphene unsuitable for room temperature transistors with a sufficient on/off current ratio. Lateral constriction of charge carriers in graphene nanostructures or vertical inversion symmetry breaking in bilayer graphene are two potential strategies to mitigate this challenge, but each…
BACKGROUND: Numerous studies have demonstrated that titanium dioxide nanoparticles (TiO2 NPs) induced nephrotoxicity in animals. However, the nephrotoxic multiple molecular mechanisms are not clearly understood. METHODS: Mice were exposed to 2.5, 5 and 10 mg/kg TiO2 NPs by intragastric administration for 90 consecutiv…
Using p-aminothiophenol (PATP) molecules on a gold substrate and high-vacuum tip-enhanced Raman spectroscopy (HV-TERS), we show that the vibrational spectra of these molecules are distinctly different from those in typical surface-enhanced Raman spectroscopy. Detailed first-principles calculations help to assign the R…
A simple strategy is developed to prepare eccentrically or homogeneously loaded nanoparticles (NPs) using poly (DL-lactide-co-glycolide) (PLGA) as the encapsulation matrix in the presence of different amounts of polyvinyl alcohol (PVA) as the emulsifier. Using 2,3-bis(4-(phenyl(4-(1,2,2-triphenylvinyl)-phenyl)amino)-p…
Four novel asymmetrical diarylethenes with a pyrrole and a variable aryl unit have been synthesized. Their crystal structures and photochromic performance were systematically studied to elucidate the effects of the aromatic stabilization energy (ASE) of aryl units. Experimental results showed that their thermal stabil…
Dynamic mechanical thermal analysis (DMTA) on individual native silk fibers demonstrates changes in the dynamic mechanical properties of storage modulus and loss tangent as a function of temperature and temperature history ranging from -100 to 250 °C. These property changes are linked quantitatively to two main types…
We describe the charge transfer interactions between photoexcited CdS nanorods and mononuclear water oxidation catalysts derived from the [Ru(bpy)(tpy)Cl](+) parent structure. Upon excitation, hole transfer from CdS oxidizes the catalyst (Ru(2+) → Ru(3+)) on a 100 ps to 1 ns timescale. This is followed by 10-100 ns el…
NiO${}_{6}$ octahedral tilts in the LaNiO${}_{3}$/SrTiO${}_{3}$ superlattices are quantified using position averaged convergent beam electron diffraction in scanning transmission electron microscopy. It is shown that maintaining oxygen octahedra connectivity across the interface controls the octahedral tilts in the La…
We have carried out first-principles simulations, based on density functional theory, to obtain the atomic and electronic structure of (001) BaTiO${}_{3}$/KNbO${}_{3}$ interfaces in an isolated slab geometry. We tried different types of structures including symmetric and asymmetric configurations and variations in the…
The carrier dynamics in bulk Silicon, a paradigmatic indirect gap semiconductor, is studied by using the Baym-Kadanoff equations. Both the electron--electron(e-e) and electron--phonon(e-p) self--energies are calculated fully ab-initio by using a semi-static GW approximation in the e-e case and a Fan self-energy in the…
We describe a ``disordered local moment'' first-principles electronic structure theory which demonstrates that tricritical metamagnetism can arise in an antiferromagnetic metal due to the dependence of local moment interactions on the magnetization state. Itinerant electrons can therefore play a defining role in metam…
The work presented here was motivated by the need to develop a predictive model for thermodynamic stabilization of binary alloys that is applicable to strongly segregating size-misfit solutes, and that can use available input data for a wide range of solvent-solute combinations. This will serve as a benchmark for sele…
Cationic spherical polyelectrolyte brushes (SPBs) were synthesized by photoemulsion polymerization, consisting of a polystyrene core with a diameter around 80 nm and a poly(2-aminoethylmethacrylate hydrochloride) (PAEMH) shell with a thickness from 10 to 50 nm densely grafted on the core surface. The binding of variou…
Density functional theory (DFT) calculations for the thermal decomposition and oxidative dehydrogenation of ethanol, mechanistic aspects of water–gas shift reaction, and experimental kinetic data are integrated so as to develop and assess a comprehensive DFT-based microkinetic model of low temperature ethanol steam re…
Formation of hyperstoichiometric uranium dioxide, UO2+x, derived from the fluorite structure was investigated by means of density functional theory (DFT) calculations. Oxidation was modeled by adding oxygen atoms to UO2 fluorite supercells. For each compound ab initio molecular dynamics simulations were performed to a…
We present angle-resolved photoemission data from Cu(111). Using a focused 6 eV continuous-wave laser for photoexcitation, we achieve a high effective momentum resolution, enabling detection of the Rashba spin splitting in the Shockley surface state on Cu(111). The magnitude of the spin splitting of $\ensuremath{\Delt…
Morphotropic phase boundary (MPB) systems are characterized by the coexistence of two ferroelectric phases and are associated with anomalous piezoelectric properties. In general, such coexistence is brought about by composition induced ferroelectric-ferroelectric instability. Here we demonstrate that a pure ferroelect…