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。
Time-dependent density functional theory faces an important problem when it comes to extended systems: The long-range component of the exchange-correlation kernel ${f}_{\mathrm{xc}}$ is completely absent from local density or generalized gradient approximations, but it is believed to be present in the ``exact'' ${f}_{…
Ash deposits from four candidate power turbine synfuels were studied in an accelerated deposition test facility. The facility matches the gas temperature and velocity of modern first-stage high-pressure turbine vanes. A natural gas combustor was seeded with finely ground fuel ash particulate from four different fuels:…
We have measured magnetic susceptibility and resistivity of ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Y}}_{x}\mathrm{Co}{\mathrm{O}}_{3\ensuremath{-}\ensuremath{\delta}}$ ($x=0.1$, 0.15, 0.2, 0.215, 0.225, 0.25, 0.3, and 0.4), and found that ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Y}}_{x}\mathrm{Co}{\mathrm{O}}_{3\e…
The source of the experimentally observed anomalous behavior of the first sharp diffraction peak (FSDP) in lithium silicate glasses was determined using classical molecular dynamics simulations. Partial structure factors obtained from simulations were used to investigate the sensitivity of the total structure factor t…
Abstract A large number of one‐dimensional bundles of ZnSe nanowires with diameters ranging from 15–20 nm and lengths of up to tens of micrometers have been prepared via the thermal treatment of a ribbon‐like precursor (ZnSe·3ethylenediamine), which has been synthesized by a mixed solvothermal route, in an argon atmos…
Zinc oxide (ZnO) is a wide-band-gap semiconductor with potential optical, electronic, and mechanical applications. First-principles investigations [C. G. Van de Walle, Phys. Rev. Lett. 85, 1012 (2000)] predicted that hydrogen impurities act as shallow donors in ZnO. IR spectroscopy [M. D. McCluskey et al., Appl. Phys.…
We have grown composite epitaxial materials that consist of semimetallic ErAs nanoparticles embedded in a semiconducting In0.53Ga0.47As matrix both as superlattices and randomly distributed throughout the matrix. The presence of these particles increases the free electron concentration in the material while providing…
We investigate the physical meaning of the intrinsic crack resistance in the Griffith theory of brittle fracture by means of atomic-scale simulations. By taking cubic SiC as a typical brittle material, we show that the widely accepted identification of intrinsic crack resistance with the free surface energy underestim…
A numerical procedure has been used for the prediction of the Seebeck coefficient of a crystalline material based on its electronic band structure with the goal of testing this approach on the simple polymers polythiophene and polyaminosquaraine. The investigation of several representative materials, including the cry…
The high-frequency mobility in disordered systems is governed by transport properties on mesoscopic length scales, which makes it a sensitive probe for the amount of local order. Here we present a method to measure the energy dependence of the high frequency mobility by combining an electrochemically gated transistor…
Recent conductance measurements on multi-wall carbon nanotubes (CNTs) reveal an effective behavior similar to disordered single-wall CNTs. This is due to the fact that electric current flows essentially through the outermost shell and is strongly influenced by inhomogeneous electrostatic potential coming from the inne…
We have investigated three-dimensional magnetization structures in numerous mesoscopic Fe/Mo(110) islands by means of x-ray magnetic circular dichroism combined with photoemission electron microscopy (XMCD-PEEM). The particles are epitaxial islands with an elongated hexagonal shape with length of up to 2.5 micrometer…
Possibility for the formation of stable Al atomic wire on the Si(211) surface is investigated using density functional theory based total energy calculations. The stable adsorption sites and the surface structures at various sub-monolayer coverages of Al are presented. It is found that the most stable and natural surf…
We present a detailed microscopic study of quasi-ballistic transport in deep submicron semiconductor channels. In particular, we study the crossover between the diffusive and ballistic regimes of transport and identify signatures in the electrostatic response, electron density, and nonequilibrium electron distribution…
Deposition of CdS nanoparticles on SWCNTs produces a photoactive composite that undergoes charge transfer interactions following excitation with visible light (see Figure). The transient bleaching recovery in approximately 200 ps confirms quick deactivation of excited CdS on the SWCNT surface. Visible excitation of th…
Abstract The fracture process of six cucumber cultivars was examined to explore the mechanical properties that determine cultivar‐specific crispy and crunchy textures. The postfailure portion of the load–strain curves was targeted in cucumber compression tests. The series of fractures after the initial fracture were e…
Abstract Scanning electron microscopes are usually equipped with energy‐dispersive X‐ray detectors for electron probe microanalysis. This widespread analytical method allows investigators to determine the elemental composition of specimens with a spatial resolution of about 1 µm. However, owing to the electron–specime…
Abstract The utilization of a slug calorimeter to evaluate the thermal performance of fire resistive materials (FRMs) is presented. The basic specimen configuration consists of a ‘sandwich’, with a square central stainless‐steel plate (slug) surrounded on two sides by the FRM. This sandwich configuration provides an a…
Abstract A solvothermal route has been developed to prepare metastable wurtzite‐structure γ‐MnS hollow spheres from anhydrous manganese chloride, sulfur powder, and potassium borohydride in ethylene glycol at 150–180 °C. The metastable γ‐MnS and stable α‐MnS were characterized by X‐ray diffraction, X‐ray photoelectron…
Abstract In this study we report the synthesis of a new class of materials called hybrid periodic mesoporous organosilicas (HPMOs). By coupling a silsesquioxane precursor through at least two chemical linkages to the mesopore walls of a pre‐existing periodic mesoporous silica (PMS) or periodic mesoporous organosilica…