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。
Abstract Electrospinning is a process that employs a high static electrical potential to produce polymeric fibers of nanoscale diameter. The process has been utilized to achieve color change by electrospinning black polymer solutions to produce white fiber mats. When subsequently heated, the electrospun mats undergo a…
Monolayers of lead selenide nanocrystals of a few nanometers in height have been made by electrodeposition on a Au(111) substrate. These layers show a thickness-dependent dielectric function, which was determined using spectroscopic ellipsometry. The experimental results are compared with electronic structure calculat…
We demonstrate the electrical and optical control of ferromagnetism in semiconductor heterostructures at high temperatures of 100–117 K. The heterostructures consist of Mn delta (δ)-doped GaAs and p -type AlGaAs. We are able to isothermally change the paramagnetic state to the ferromagnetic state and vice versa , by a…
Abstract EPICLON [3a,4,5,7a‐Tetrahydro‐7‐methyl‐5‐(tetrahydro‐2,5‐dioxo‐3‐furanyl)‐1,3‐isobenzofurandione] or [5‐(2,5‐dioxotetrahydrofurfuryl)‐3‐methyl‐3‐cyclohexyl‐1,2‐dicarboxylic acid anhydride] ( 1 ) was reacted with L ‐phenylalanine ( 2 ) in acetic acid, and the resulting amic acid was refluxed under a Dean‐Stark…
The high frequency dynamics of glassy selenium has been studied by inelastic x-ray scattering at beam line BL35XU (SPring-8). The high quality of the data allows one to pinpoint the existence of a dispersing acoustic mode for wave vectors ($Q$) of $1.5<Q<12.5\text{ }{\mathrm{n}\mathrm{m}}^{\ensuremath{-}1}$, hel…
In this work, the inter-relationship between the microstructure, the grain boundary electronic structure, and the high- and low-field electrical properties of the positive temperature coefficient of resistivity BaTiO 3 ceramic thermistors was explored. At high temperatures, the resistance of the material is strongly d…
Abstract Water‐soluble sulfonated acetone–formaldehyde (SAF) resins were synthesized by the reaction among acetone, formaldehyde, and sodium bisulfite. The factors affecting the properties of SAF resins and optimum conditions of preparation were investigated. The SAF resins prepared under proper conditions have good w…
Abstract Syndiotactic polypropylene (sPP) sheets of various crystallinities were subjected to accelerated ultraviolet (UV) aging. The chemical modification of the polymer was followed by FTIR spectroscopy measuring the carbonyl index in transmittance (film) and diffuse reflectance (powder) modes. Both the tensile stre…
Isolated single-walled carbon nanotubes (SWNTs), SWNT bundles, and ropes (or strands) show a structural self-similar characteristic. By calculating the Hausdorff dimension, it was found that their self-similar organization leads to surface fractality and the value of the surface dimension ${(D}_{s})$ depends on self-s…
Dielectric relaxation in disordered dielectric mixtures is presented by emphasizing the interfacial polarization. The obtained results coincide with and cause confusion with those of the low frequency dispersion behaviour. The considered systems are composed of two phases on two-dimensional square and triangular topol…
We demonstrate a tunable-focus microlens array using polymer network liquid crystals (PNLCs). PNLCs were prepared by ultraviolet (UV) light exposure through a patterned photomask. The UV-curable monomer in each of the exposed spots forms an inhomogeneous centro-symmetrical polymer network that functions as a lens when…
Abstract In this work, the shear‐induced crystalline layers of isotactic polypropylene (i‐PP), developed in a slit die, were characterized by different techniques. Rheological studies made in a strain‐controlled rheometer, at different crystallization temperatures, T c , allowed us to observe that the induction time f…
New thermally responsive fluorescent polymers conjugated with poly( N -isopropylacrylamide) (polyNIPA) have been synthesized. A nonionic water-soluble poly(phenylene−ethynylene) (PPE) was end-capped with a di- tert -butylnitroxide derivative, and subsequent nitroxide-mediated radical polymerization of NIPA afforded PP…
Abstract An aqueous dispersible polyurethane was prepared by the reaction of hydroxyl‐terminated poly(ethylene adipate), dimethylol propionic acid, 4,4′‐diphenylmethane diisocyanate, and ethylene glycol. Formation of the dispersion was achieved by phase inversion of an acetone solution of the polyurethane with water,…
Abstract A series of heterocyclically conjugated polymer–clay nanocomposite (PCN) materials that consisted of organic poly(3‐hexylthiophene) (P3HT) and inorganic montmorillonite (MMT) clay platelets were prepared by in situ oxidative polymerization with FeCl 3 as an oxidant. The as‐synthesized PCN materials were chara…
Coherently-grown heteroepitaxial oxide thin films on single crystal substrates are always under elastic strain. This strain causes changes in the physical properties of thin films. We have studied the behavior of anisotropic magnetic properties of SrRuO 3 films grown directly on SrTiO 3 and on Ba 1- x Sr x TiO 3 /BaTi…
[structure: see text] Snowflake-shaped dendrimers were prepared via site-selective synthesis of dendrons, where an attachment of encapsulating dendritic branches and an extension of phenylacetylenic units were alternatively manipulated on the structure of AB(2) (diethyltriazeno for A and bromo for B) substituted diphe…
A crystalline graphitic structure—uniform diameter, thin‐walled carbon microtubes (see Figure)—has been prepared via a thermal reaction between ZnS and activated carbon. The microtubes have outer diameters of ∼ 1–2 μm, wall thicknesses of 10–20 nm, and lengths from several hundreds of micrometers to millimeters. The f…
Abstract A series of nanocomposite materials consisting of water‐soluble polyacrylamide (PAA) and layered montmorillonite (MMT) clay platelets were prepared by the effective dispersion of the inorganic nanolayers of the MMT clay in the organic PAA matrix via in situ ultraviolet‐radiation polymerization. The acrylamide…
Magnetically driven self‐assembly of colloidal particles into highly ordered structures on a substrate is demonstrated. This process allows for programming of specific geometrical patterns of colloidal particles. It also permits assembly of well‐defined colloidal patterns of many different particle types, possibly car…