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。
Transcription of organic templates into shapely inorganic materials is generally believed to occur because of charge or hydrogen bonding interactions between the template and the inorganic precursor; the formation of the inorganic material is always promoted by a catalyst present in solution. In this paper, we prove f…
The behavior of the third-order nonlinear dynamic dielectric susceptibility ${\ensuremath{\chi}}_{3}(\ensuremath{\omega})$ in relaxor ferroelectrics is investigated in the framework of the spherical random-bond--random-field model. It is shown that there are two distinct contributions to ${\ensuremath{\chi}}_{3}(\ensu…
Like spiral staircases connecting the floors of a building, twisted chiral organic “pillars” link hydrogen-bonded guanidinium sulfonate sheets and produce extended supramolecular helices (see picture) that wind through crystals with predictable three-dimensional architectures.
Three color states and a large luminance change at intermediate potentials are the key features of a new alkylenedioxypolythiophene, in which two polymeric strands are linked by a spiro(bis-dioxacycloheptene) unit (see Figure). The seven-membered rings are quite flexible and allow coplanarity of both strands. The poly…
Three-coordinate 1 ∶ 1 and 1 ∶ 2 compounds of copper(I) halides with tricyclohexylphosphine have been synthesised and characterized by single crystal X-ray structure determinations, 63Cu NQR spectroscopy, solid state 31P CPMAS NMR spectroscopy, and low frequency vibrational spectroscopy. The 1 ∶ 1 compounds crystalliz…
The application of a Genetic Algorithm, for optimising the geometry of aluminium clusters with 21-55 atoms bound by the many-body Murrell-Mottram potential, is described. In this size regime, a number of different structural motifs are identified--face-centred cubic, hexagonal close packed, decahedral and icosahedral…
Direct decomposition of NO to N2 by rare earth oxides prereduced with H2 was studied. CeO2 and Pr6O11 prereduced at 773 K, in which many oxygen anion vacancies exist, decomposed NO to N2 at 673 K. The addition of Pt accelerated the dissociation of NO to N2. The amount of NO decomposed to N2 and N2O by Pt supported on…
A cholesteric mixture based on a menthyl-containing copolymer, photosensitive chiral dopant, mesogenic diacrylate, and photoinitiating agent has been prepared. The mixture shows a selective light reflection in the visible light spectral region. The action of UV irradiation (313 or 365 nm) on the planar-oriented films…
Helices auf Helices: Nanohelices aus polykristallinem Cadmiumsulfid (siehe elektronenmikroskopische Aufnahme) wurden durch Mineralisation in Gegenwart eines selbstorganisierten Templats hergestellt, das die Gestalt eines verdrillten Bandes aufweist. Die korkenzieherförmige Morphologie der anorganischen Helices resulti…
“Nanosecond” electrochemistry is used to study acoustically emulsified mixtures of aqueous electrolyte and smaller quantities of heptane. Significant current spikes of microsecond duration are observed under potentiostatic conditions and attributed to the impacting of heptane droplets onto the electrode surface. The p…
Poly(ethylene glycol) containing surfactant molecules were modified with titanium alkoxides. These surfactants were used in the synthesis of mesostructured silica−titania mixed metal oxide thin films serving two different functions: (a) as a structure-directing agent and (b) as a moderator of the hydrolysis rate of th…
The amphiphilic shape-persistent macrocycle 1 containing four phenol-OH groups as polar side groups and four hexyloxy groups as nonpolar side groups in an adaptable arrangement was recrystallized from solvents of different polarity. X-ray crystallography reveals that the conformation of the macrocycle is solvent depen…
Fluorine-doped polypyrroles, combining the electrical properties of conducting polymers and the unique surface properties of fluorinated molecules, have been obtained by an easy and straightforward method. Using the fluorine co-dopant, fabrics with hydrophobic, fluorinated surfaces have been created, and a selective d…
Piezoelectric properties of Na 0.5 Bi 0.5 TiO 3 ceramics have been investigated over a broad temperature range using a resonance technique. The thermal behaviours of the piezoelectric tensor coefficients d 31 , d 33 and d 15 confirm that there is a distinct phase transformation at 200 °C. For the first time it has bee…
Silver dendritic nanostructures protected by tetrathiafulvalene (TTF) were synthesized via reduction of silver ions with TTF in acetonitrile.
We introduce a generic Fröhlich-Coulomb model of the oxides, which also includes infinite on-site (Hubbard) repulsion, and describe a simple analytical method of solving the multi-polaron problem in complex lattice structures. Two particular lattices, a zigzag ladder and a perovskite layer, are studied. We find that,…
Controlled synthesis of transition metal complexes with mixed ligands has led to two new compounds with the same empirical formula [Fe(N3)2(4,4'-bpy)] (4,4'-bpy=4,4'- bipyridine). The compound 2D-[Fe(N3)2(4,4'-bpy)] (I) contains end-on (EO) bridging azido ligands. It crystallizes in the orthorhombic crystal system, sp…
We report the first use of ultrafast (subpicosecond) laser pulses for large-scale production of single wall carbon nanotubes (SWNT's) by the pulsed laser vaporization (PLV) technique. Very high production rates were achieved; using only 20% of the nominal average power of the 1 kW Jefferson Lab free electron laser (Jl…
In this study, we use a novel method for simultaneously measuring the optical and electrochemical properties of layer-by-layer self-assembled conducting ultrathin polymer films. We employed the recently developed combination of in situ surface plasmon resonance spectroscopy (SPS) and surface plasmon field-enhanced lig…
Solid and hollow metallo-dielectric spheres are created by layer-by-layer self-assembly. The discrete metallic nanoparticles, which make up the shell, form a contiguous layer that exhibits a collective plasmon resonance with a splitting of the dipole mode into transverse and longitudinal modes. The splitting can be co…