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。
Fully dense polycrystalline Ti3AlC2 was fabricated by a solid–liquid reaction synthesis and simultaneous in-situ hot pressing of a mixture of Ti, Al and graphite powders at 1500 °C and 25 MPa for 5 minutes and subsequently annealing at 1200 °C for 20 minutes. The effects of various parameters including composition of…
Abstract Polysiloxane ionomers bearing pendant quaternary ammonium groups were synthesized through the Menshutkin reaction of poly(γ‐chloropropylmethylsiloxane‐ co ‐dimethylsiloxane) with N , N ‐dimethylbenzylamine. Ion aggregation in the ionomers with different contents of the quaternary ammonium groups was investiga…
The purpose of this paper is to present basic functional principles of high frequency x-ray generators. The emphasis is put on physical concepts that determine the engineering solutions to the problem of efficient generation and control of high voltage power required to drive the x-ray tube. The physics of magneticall…
Assistive technology, specifically in the area of wheelchair seating, has advanced tremendously in the past decade. Over 200 wheelchair cushion models are commercially available. This increased selection brings greater options to the end user. However, having more options places greater importance on the ability to ma…
The structures of poly(1,4-phenylenesulfone), [1,4-ArSO 2 ] n (Ar = 1,4-phenylene), and its tetrasulfone oligomer ArSO 2 ArSO 2 ArSO 2 ArSO 2 Ar (Ar = phenyl or 1,4-phenylene) have been determined from X-ray powder diffraction data interfaced to molecular simulation and diffraction modeling. An initial model for the t…
A third generation poly(propylene imine) dendrimer functionalized with oligo(phenylene vinylene) groups is used as a stabilizing agent in the fabrication of CdS nanoparticles. The solvent-dependent conformational behavior of this electroactive dendrimer is used to generate various organic−inorganic semiconductor compo…
Cluster-derived bimetallic nanoparticles have been deposited onto multi-wall carbon nanotubes and shown to be generally homogeneously dispersed, of uniform small sizes, of the same composition as the starting mixed-metal clusters, and to have a tendency to align at the tips of the tubules.
$B$-site substitution effects on the structural and magnetic properties are investigated in ${\mathrm{Nd}}_{1/2}{\mathrm{Ca}}_{1/2}$$({\mathrm{Mn}}_{0.97}{M}_{0.03})$${\mathrm{O}}_{3}$ $(M=\mathrm{Al},$ Zn, Sc, Fe, Ni, Co, and Cr). With decreases of temperature below $\ensuremath{\sim}200 \mathrm{K},$ these compounds…
The local structure and electronic state of a photomagnetic material ${\mathrm{Cs}}_{0.8}{\mathrm{Co}}_{1.1}(3\ensuremath{-}\mathrm{cyanopyridine}{)}_{1.9}\mathrm{W}(\mathrm{CN}{)}_{8}\ensuremath{\cdot}2.1{\mathrm{H}}_{2}\mathrm{O}$ have been investigated by means of x-ray-absorption fine structure (XAFS) spectroscopy…
A new rod-like coordination polymer consisting of (Ru-(terpy)2) motifs bridged by bithiophene units has been prepared by electrochemical polymerisation in acidic organic medium.
The magnetic anisotropy of a novel Mn(II)- [3x3] grid complex was investigated by means of high-field torque magnetometry. Torque vs field curves at low temperatures demonstrates a ground state with S>0 and exhibits a torque step due to a field-induced level crossing at B(*) approximately 7.5 T, accompanied by an abru…
This paper presents structural studies on crystalline and liquid AsCl(3), performed using X-ray diffraction (XRD) and wide-angle X-ray scattering (WAXS) in the 176-250 K temperature range and at 295 K for the crystalline and liquid samples, respectively. The XRD results, collected using a single-crystal diffractometer…
Abstract A comprehensive mathematical model was established by considering the main and side reactions for solid‐state polycondensation of poly(ethylene terephthalate). The effect of temperature on chain mobility was used to estimate the rate constants of chemical reactions. The polymer crystalline fraction was modele…
Abstract Heat‐curable silicone rubber (HCSR) was prepared by using vinyl‐containing silicone resin (VSR) as the crosslinking agent instead of polyvinylsilicone oil (C gum). Mechanical properties and crosslink density of the vulcanizates were measured. The results indicate that VSR is a good crosslinking agent for HCSR…
The development of an artificial graft requires formulation of biomechanical design criteria. The compliance of artifical grafts, based on the intraluminal pressure-internal diameter (Pi-Di) relationship, was measured by a novel method using a digital X-ray imaging system coupled with an edge detection algorithm and a…
The synthesis, characterization, and X-ray structure of a heptapyrrolic macrocycle, [30]heptaphyrin(1.1.1.1.1.0.0) is reported; despite showing aromatic features, it exhibits a 'figure eight'-like structure in the solid state.
Spinel structure ${\mathrm{MnFe}}_{2}{\mathrm{O}}_{4}$ is investigated using density functional calculations. The ground state is a high spin ferrimagnet in agreement with experiment. The band structure shows a low carrier density half metal in the fully ordered state, in contrast to experimental characterizations of…
Synthesis and characterization of poly(quinoxaline vinylene)s and poly(pyridopyrazine vinylene)s with linear and branched aliphatic side chains are reported. The electron affinity of the polymers was measured with cyclic voltammetry (CV) and found to be highest for the pyridopyrazine vinylene polymers. Compared to CN-…
The magnetic and electrical transport properties and relative thermal expansion measurements on ${\mathrm{GdBaCo}}_{2}{\mathrm{O}}_{5.45}$ show the existence of a stabilized intermediate spin state of ${\mathrm{Co}}^{3+}$ in the temperature region $108 \mathrm{K}<~T<~365 \mathrm{K}.$ A charge ordering effect at…
We study the nonequilibrium fluctuation-dissipation theorem (FDT) in the glass phase of Bouchaud's trap model. We incorporate an arbitrary observable m and obtain its correlation and response functions in closed form. A limiting nonequilibrium FDT plot is approached at long times for most choices of m. In contrast to…