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。
In semicrystalline isotactic Polypropylene the sensitivity to crack propagation can be lowered by the right choice of the molecular composition (atactic content, molecualr weight) and by a controlled production of a certain morphology. Coarse spherulitic morphologies produced by slow undercooling from the melt exhibit…
In bulk isotactic polypropylene it is relatively easy to change the morphology of the material in a wide range, mainly by different isothermal crystallization conditions. Size, distribution and inner structure of the spherulites have a great influence on the crack propagation in this material. Due to our microscopic i…
Abstract Artelon® (degradable poly(urethane urea) elastomer) was electrospun into scaffolds for tissue engineering. The diameter of the electrospun fibers, studied by scanning electron microscopy, ranged from 100 nm to a few μm, with an average diameter of 750 nm. The molar mass of the polymer had a major influence on…
The two-point correlation functions among particles confined to move within a spherical two-dimensional space are studied here using Monte Carlo simulations in the canonical ensemble and the corresponding liquid theory concepts. This work takes a simple model system with soft-sphere interactions among the particles ly…
X-ray photoelectron spectroscopy has been used to measure the valence band offset at the ZnO∕GaAs heterojunction interface. The valence band offset is determined to be 2.39±0.23eV. As a consequence, a type-II heterojunction with a conduction band offset of −0.44±0.23eV is found. The directly obtained value is in good…
Acoustic emission measurements are combined with strain, dielectric, and polarization measurements to detect phase transitions in 0.94Na0.5Bi0.5TiO3–0.06BaTiO3 single crystals during thermal cycling as well as electric field cycling at both room temperature and 140°C. All phase transitions known from the literature (c…
Constant-potential electrochemical synthesis of ZnO on metal substrates enables selective formation of either Ohmic or Schottky-barrier contacts. Using a mildly acidic nitrate-based aqueous electrolyte, there is a substrate-dependent deposition potential below which electrodeposited ZnO heterojunctions display Schottk…
The surfaces of epitaxial BaTiO3 films on SrTiO3 substrates were investigated by x-ray reflectivity (XRR) and angle-resolved x-ray photoelectron spectroscopy (ARXPS). It was shown by XRR analysis that there exists a low electron density surface layer (about 87%–93% of the electron density of the underneath BaTiO3 laye…
The photoabsorption spectra of a continuous series of Na(n) clusters (n<or=14, n=20, n=40) have been calculated using a time-dependent density-functional scheme. Accordingly, we present these spectra and show that they are in very good agreement with other theoretically and experimentally obtained photoabsorption spec…
Abstract Three discrete dinuclear copper(II)–lanthanide(III) complexes, namely, [CuLn(mmi) 2 (NO 3 ) 3 (H 2 O) 2 ] [Ln = La ( 1 ), Sm ( 2 )] and [CuGd(mmi) 2 (NO 3 ) 2 (H 2 O) 3 ][NO 3 ] ( 3 ) (Hmmi = 2‐hydroxymethyl‐1‐methylimidazole) were synthesized and structurally characterized by X‐ray diffraction analysis. In t…
Metal-insulator-metal capacitors with high-k Ba[(Ni1∕2,W1∕2)0.1Ti0.9]O3 thin film dielectrics were fabricated by chemical solution deposition technique. High dielectric constant (85), low dielectric loss (0.007), and high breakdown field (∼3.0MV∕cm) at room temperature were achieved. The temperature and frequency depe…
Abstract The thermal behavior of the metallomesogens [Ln(C 12 C 16 dbm) 3 (phen)] (Ln = La, Nd, Eu, Gd, Tb, Dy, Er, Yb; C 12 C 16 dbm = 1‐(4‐dodecyloxyphenyl)‐3‐(4‐hexadecyloxyphenyl)propane‐1,3‐dionate; phen = 1,10‐phenanthroline) was investigated. The complexes of the light lanthanides (Ln = La, Nd) are not mesomorp…
Abstract Three tricyanometalate precursors, (Bu 4 N)[(PhTp)Fe(CN) 3 ] · H 2 O ( 1 ), (Bu 4 N)[(MeTp)Fe(CN) 3 ] ( 2 ), and (Bu 4 N)[( i BuTp)Fe(CN) 3 ] ( 3 ) [Bu 4 N + = tetrabutylammonium cation; PhTp = tris(pyrazolyl)phenylborate; MeTp = methyltris(pyrazolyl)borate; i BuTp = 2‐methylpropyltris(pyrazolyl)borate], were…
Using the density-functional theory combined with the nudged elastic band method, we have calculated migration pathways and estimated the activation energy barriers for the diffusion of Ag ions in low-temperature Ag2S. The activation energy barriers for four essential migrations for an Ag ion, namely, from a tetrahedr…
We have performed time-dependent density functional theory and $GW$/Bethe-Salpeter calculations of the optical properties of a series of CdSe clusters ranging in size from 10 to 82 atoms and passivated by fictitious atoms of half-integer charge. The two methods predict a different character of the optical excitations…
In this study, the mechanical properties, deformation behavior, and fracture modes of iron-silicon melt-spun ribbons are related to changes in silicon composition from 4.5 to 6.5 wt pct and the influence of ordering phase transformations. The as-solidified melt-spun ribbons, which exhibit plasticity even for the Fe-6.…
The crystal structures, filling fraction limits (FFLs), electronic structures, and electrical transport properties for alkali-metal-filled $\mathrm{Co}{\mathrm{Sb}}_{3}$ skutterudites are studied using density functional band-structure calculations. The calculated FFLs in $\mathrm{Co}{\mathrm{Sb}}_{3}$ are more than 6…
Magnetotransport and magnetocaloric properties of polycrystalline Pr0.65(Ca0.7Sr0.3)MnO3 have been studied. Large low field magnetoresistance (∼100% at 75K for 1T field) with high magnetic field sensitivity (∼5000%T−1) has been observed due to the melting of charge ordered state. The system also shows large magnetocal…
Single- and multiphase samples of the n-type half-Heusler NbCoSn were prepared by directional solidification using the optical floating zone melting method, and the thermoelectric properties of these samples were evaluated. NbCoSn has an excellent thermoelectric power which exceeds −250μVK−1 at around 900K and a relat…
An Aurivillius phase bismuth layer‐structured compound potassium bismuth titanate is synthesized using conventional solid‐state processing. It was found that the range of sintering temperature for the potassium bismuth titanate is very narrow. Phase analysis was performed by X‐ray diffraction, and microstructural morp…