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 third nonlinear optical susceptibility (χ〈3〉) of a new family of octupolar molecules with one, two, and three double bonds has been measured at 532 in tetrahydrofuran solutions by the degenerate four-wave mixing (DFWM) method. For comparison, we also measured the analogous dipolar subunits of the molecules. The se…
Porphyrins can be substituted easily and in high yield at the meso positions by using organolithium reagents. When S4-symmetric porphyrins such as 2,3,7,8,12,13,17,18-octaethylporphyrins are used as starting materials, it is possible to perform four such substitution reactions in sequence, resulting in the formation o…
The formation process of point defect clusters in high-purity (99.999%) iron as a typical bcc metal under the irradiation with low-energy (5 keV)He+ is studied by in situ transmission electron microscopy (TEM). Using conventional TEM techniques, clusters induced by the irradiation are determined to be interstitial-typ…
Leakage current measurements are performed on prototype cells revealing an S-shaped current versus voltage curve. This result indicates the presence of ion generation and recombination in the liquid crystal bulk. The compensation of the electrical field and the saturation current are related to the alignment layer thi…
The operation of railway track is likely to involve the presence of solid contaminants on the line at some stage. This may be from the dispersion of freight goods such as coal or minerals, or the presence of ballast stone thrown on to the track either by the passage of the train or during ballast cleaning operations.…
In the framework of the Peierls model generalized to two dimensions the dissociation of a dislocation in the {111} plane of a fcc lattice into two Shockley partials is studied by a variational procedure. Each partial is made up by a distribution of infinitesimal dislocations with a density obtained by a superposition…
Microstructural development of thin‐film barium strontium titanate (Ba x Sr 1– x TiO 3 ) as a function of strontium concentration and thermal treatment were studied, using transmission electron microscopy (TEM) and X‐ray diffractometry (XRD). Thin films, ∼250 nm thick, were spin‐coated onto Pt/Ti/SiO 2 /Si substrates,…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTN-Confused Expanded Porphyrin: First Example of a Modified Sapphyrin with an Inverted N-Confused Pyrrole RingSimi K. Pushpan, Alagar Srinivasan, Venkataramanarao G. Anand, Sundararaman Venkatraman, Tavarekere K. Chandrashekar, Bhavani S. Joshi, Raja Roy, and Hiroyuki F…
Abstract The dynamic mechanical behavior of molecularly oriented semicrystalline polyethylene terephthalate (PET) induced via the equal‐channel angular extrusion (ECAE) process was investigated. Dynamic mechanical analyses in both torsional mode and bending mode were utilized. The results indicate that the ECAE‐orient…
A banded spherulite of bacterial poly(3-hydroxybutyrate) (band spacing 120 μm) was linearly scanned along the radial direction in 3 μm steps by means of microfocus X-ray diffraction using a synchrotron source with a beam diameter of 3 μm. A large number of X-ray patterns was collected inside each band. Those taken at…
The deformation of Cu single crystals at 4.2 K was studied by simultaneous measurements of mechanical and electrical properties. The aim was to extend the study of low-temperature deformation to higher strains than are usually employed; thus most of the crystals were stretched to failure. The deformation can be divide…
Very accurate electron structure factors measured by a significantly improved transmission electron diffraction technique for polycrystalline samples were used in a high-resolution quantitative study of the electrostatic potentials in LiF, NaF, and MgO crystals. The spatial electrostatic potential distribution was obt…
The temperature dependence of the surface tension was measured by the pendant drop method for four compounds from the homologous series of alkylcyanobiphenyls (nCB), in the nematic liquid crystal and isotropic phases. For 8CB (octylcyanobiphenyl) the temperature dependence was also measured in the smectic range. Not v…
Vascular corrosion casting has been used for about 40 years to produce replicas of normal and abnormal vasculature and microvasculature of various tissues and organs that could be viewed at the ultrastructural level. In combination with scanning electron microscopy (SEM), the primary application of corrosion casting h…
The reaction of hexacyanochromate(III) with Ni(tmc)2+ (tmc = tetramethylcyclam) leads to the formation of the layered compound [Ni(tmc)]3[Cr(CN)6]2·18H2O displaying a corrugated sheet structure. Within each layer, the Ni(tmc) units are surrounded by two Cr(CN)6 complexes in a trans fashion while the Cr(CN)6 units are…
Methods of characterizing colloidal interaction potentials of nanoscale silver particles during their formation are discussed. Silver sols are produced by the borohydride reduction of silver perchlorate, and their colloidal stability is found to vary both with reaction conditions and over the course of the reaction. S…
Novel, soluble poly(9,9-dialkylfluorene)/poly(2-alkylaniline) block copolymers were synthesized following a three-step synthetic procedure: (i) aryl-aryl coupling of alkylated dibromofluorenes and fluorene diboronic esters according to Suzuki in the presence of 4-nitrobromobenzene as a monofunctional end-capping reage…
The formation of Ni surface precipitates on natural soil materials may occur during sorption under ambient environmental conditions. In this study, we examined proton‐ and ligand‐promoted dissolution of Ni surface precipitates on pyrophyllite, talc, gibbsite, amorphous silica, and a mixture of gibbsite and amorphous s…
We report the orientations of thermotropic liquid crystals to be coupled through dipolar interactions to the electric fields of electrical double layers that form upon contact of the liquid crystals with model surfaces presenting sodium carboxylate salts. The surfaces were prepared by the self-assembly of HOOC(CH 2 )…
Indium tin oxide (ITO) thin films were deposited on polymeric substrates at room temperature by dc reactive magnetron sputtering from an In–Sn (90–10 wt%) alloy target. The electrical, optical, and mechanical properties of ITO films on various substrates such as polycarbonate, acrylic, polyethylene terephthalate, and…