Materials Literature
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We report B-LYP/6-31G* and B3-LYP/6-31G* density functional theory calculations on a set of polycyclic hydrocarbons, ranging in size from C 19 H 22 to C 36 H 32 , combining aromatic (unsaturated) and aliphatic (saturated, sp 3 -hybridized carbon) ring systems. These locally aromatic polycyclic hydrocarbons (LAPHs), ge…
Complex permittivity measurements were performed on sorbitol, xylitol, and sorbitol-xylitol mixture in the supercooled liquid state in an extremely wide frequency range from 10 microHz to 500 MHz at temperatures near and above the glass transition temperature. We determined detailed behavior of the relaxation paramete…
We investigated the electronic structures of chemically modified carbon nanotube tips under electric fields using density functional calculations. Hydrogen, oxygen, and hydroxyl group-terminated nanotubes have been considered as field emitters or probe tips. In the case of the open-ended tubes, the field emission orig…
Continuum theory is used to demonstrate that the presence of flexoelectricity significantly alters the response to an applied voltage of a homogeneous nematic liquid crystal cell above the ac Fréedericksz threshold voltage. In such a system there is a fitting degeneracy: we obtain very good fits between theory and exp…
Water-soluble chitooligosaccharides have been reported to have specific biological activities. In this study, the chitosan samples with different degree of acetylation were used separately to prepare chitooligosaccharide (COS) and highly deacetylated chitooligosaccharide (HDCOS) through the nitrous acid depolymerizati…
The structural and electronic properties of ${\mathrm{BaTiO}}_{3}$ (001) slabs in paraelectric (PE) phase and ferroelectric (FE) phases with a [001] FE distortion are investigated by first-principles calculations to explore a possible scenario for the surface conduction recently observed in the FE phase. Both ${\mathr…
Dendritic polymer-modified porous silica particles prepared by a poly(amidoamine) (PAMAM) dendrimer synthesis reaction were characterized by elementary analysis (EA) and size exclusion chromatography (SEC). EA demonstrated the successful alternate growth of dendritic layers on the particles. The phased growth of polym…
Conducting polymers are important materials for several applications, among them, newly developed sensors that are based on changes in the conductivity of polyaniline (PANI). These sensors usually have pH limitations related to PANI characteristics (need for positive charge on the nitrogen atoms to get high conductivi…
In searching for new and efficient mechanisms for moving or propelling nano-sized objects across a flat surface, we discuss the idea of using the periodically switchable topography of a certain class of polymer substrates. In this paper, we exploit the peculiar properties of diblock-copolymer and mixed brushes that ca…
We present a 13 C labelling method for revealing the growth model of the carbon nanotubes and monitoring the detailed growth process of a multi-walled carbon nanotube (MWNT) array. 13 C ethylene and 12 C ethylene are fed into the chemical vapour deposition (CVD) reactor with pre-designed time sequences to growth MWNT…
By performing extensive angle-resolved photoemission measurements using tunable linearly polarized synchrotron radiation with photon energies from 15 to 31 eV on high quality cleaved samples we have succeeded in experimentally mapping the occupied electronic bands of GaSe(0001) along all key symmetry directions. The e…
The light fantastic: The first examples of soluble high-molecular-weight d10 mercury(II) polyyne copolymers incorporating a 9,9-dialkylfluorene moiety have been prepared and photophysically characterized (see picture). These polymers have been shown to utilize a heavy-atom effect in exhibiting strong phosphorescence.
A computer simulation study of the Ce 4+ /Ce 3+ reduction process in CeO 2 −MO (M = Ca, Mn, Ni, Zn) and CeO 2 −M 2 O 3 (M = Sc, Mn, Y, Gd, La) mixed oxides is presented. Calculations satisfactorily reproduce the observed structural parameters of the solid solutions over a wide range of compositions. On energetic groun…
We report on the generation of assemblies comprising number density gradients of nanoparticles in two (2D) and three (3D) dimensions. These structures are fabricated by creating a surface-bound organic template which directs the spatial arrangement of gold nanoparticles. The 2D template is made of amine-terminated org…
Lamellar and hexagonal structures of new silica-based hybrids were directly formed from newly designed alkylsiloxane oligomers 1. This approach based on the self-assembly of single precursors provides a novel pathway to ordered microporous silica as well as mesostructured silica-based hybrid materials (see scheme, 1)…
The use of recent advances in resonance Raman spectroscopy studies on isolated carbon nanotubes and the scientific knowledge achieved so far from these studies is discussed in the context of advancing carbon nanotube-based technology. Changes in the Raman spectra can be used to probe and monitor structural modificatio…
We have undertaken an inelastic neutron scattering study of the perovskite relaxor ferroelectric $\mathrm{P}\mathrm{b}({\mathrm{Z}\mathrm{n}}_{1/3}{\mathrm{N}\mathrm{b}}_{2/3}){\mathrm{O}}_{3}$ with 8% ${\mathrm{P}\mathrm{b}\mathrm{T}\mathrm{i}\mathrm{O}}_{3}$ (PZN-8%PT) in order to elucidate the origin of the previou…
The chemical states of the ${\mathrm{Z}\mathrm{n}\mathrm{G}\mathrm{e}\mathrm{P}}_{2}\ensuremath{\mathbin:}\mathrm{M}\mathrm{n}$ interface which shows ferromagnetism above room temperature have been studied by photoemission spectroscopy. Mn deposition on the ${\mathrm{Z}\mathrm{n}\mathrm{G}\mathrm{e}\mathrm{P}}_{2}$ su…
A solid-state quantum computer with dipolar coupling between qubits is proposed. The qubits are formed by the low-lying states of an isolated acceptor in silicon. The system has the scalability inherent to spin-based solid state systems, but the spatial separation between the qubits is an order of magnitude larger. De…
The electron spin is emerging as a new powerful tool in the electronics and optics industries. Many proposed applications involve the creation of spin currents, which so far have proven to be difficult to produce in semiconductor environments. A new theoretical analysis shows this might be achieved using holes rather…