Materials Literature
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X-ray absorption (XAS) and core level photoelectron spectroscopy are versatile tools to site selectively study the unoccupied density of states and bonding environment. Hence, they are widely applied to study single-wall carbon nanotubes (SWCNTs) as archetypes of one-dimensional solids. However, their van Hove singula…
Nanocomposite oxides of Ce x Zr 1- x O 2 dispersed over alumina (Al 2 O 3 ), silica (SiO 2 ), and titania (TiO 2 ) have been synthesized by a deposition coprecipitation method. The physicochemical characterization was carried out by X-ray diffraction (XRD), Raman spectroscopy, high-resolution electron microscopy (HREM…
Calming the radicals: Aminyl radicals may one day be useful oxidation catalysts if their thermodynamic instability can be overcome, for example, through complexation with a metal. The semiquinone–anilino-radical and catechol–anilino-radical complexes 1 and 2 have now been prepared and the anilino-radical character of…
The half-Heusler compounds ErPdSb and YPdSb were studied by means of x-ray diffraction, magnetic susceptibility, electrical resistivity, magnetoresistivity, thermoelectric power, Hall effect, thermal conductivity, and specific heat measurements, performed in the temperature range $1.5--300\phantom{\rule{0.3em}{0ex}}\m…
Abstract Metallopolymere haben sich in den letzten Jahrzehnten zu einem ergiebigen Forschungsgebiet entwickelt. Besonders die Polyferrocenylsilan(PFS)‐Chemie hat sich dabei rasant entwickelt. Nach Entdeckung der thermischen Ringöffnungspolymerisation (ROP) von Sila[1]ferrocenophanen konnten Polyferrocenylsilane bald a…
Pure and Nb‐substituted CaCu 3 Ti 4− x Nb x O 12+ x /2 (CCTO, x =0, 0.02, 0.1, 0.2, 0.4) ceramics were prepared by a conventional solid‐state sintering, and their electric and dielectric properties were investigated using an impedance analyzer. A single‐phase CCTO was obtained up to x =0.2 Nb substitution and the latt…
Heart valve replacement represents the most common surgical therapy for end-stage valvular heart diseases. A major drawback that all contemporary heart valve replacements have in common is the lack of growth, repair and remodelling capability. In order to overcome these limitations, the emerging new field of tissue en…
Abstract Das Elektrospinnen ist eine vielseitige Methode, um aus Lösungen und Schmelzen, vorwiegend von Polymeren, kontinuierliche Fasern mit Durchmessern von wenigen Mikrometern bis zu wenigen Nanometern herzustellen. Die Methode ist vielseitig anwendbar, da sich nahezu alle löslichen und schmelzbaren Polymere einset…
High Resolution Image Download MS PowerPoint Slide Octahedral clusters (CeO 2 - x ) n ( n ≤ 85) have been studied using a density functional method (DFT+U) adapted to model nanocrystalline ceria. The binding energies of the clusters Ce 19 O 32, Ce 44 O 80, and Ce 85 O 160 are shown to converge to the bulk limit almost…
An exciton evolving from an m -fold degenerate hole level and an n -fold degenerate electron level has a nominal m × n degeneracy, which is often removed by electron−hole interactions. In PbSe quantum dots, the degeneracy of the lowest-energy exciton is m × n = 64 because both the valence-band maximum and the conducti…
There is a plethora of experimental data on the dynamics of water in mixtures with glycerol, ethylene glycol, ethylene glycol oligomers, poly(ethylene glycol) 400 and 600, propanol, poly(vinyl pyrrolidone), poly(vinyl methylether), and other substances. In spite of the differences in the water contents, the chemical c…
Abstract Thin films of ZnS: Cu nanoparticles were deposited in chemical bath by a pH controlled solution synthesis technique. The copper concentration was varied from 0 to 0.1M%. XRD and SEM indicated variations in diffracted intensity and morphology with Cu concentration. The PL spectrum of the undoped ZnS nanopartic…
We report on the synthesis of C-BN single-walled nanotubes made of BN nanodomains embedded into a graphene layer. The synthesis process consists of vaporizing, by a continuous CO2 laser, a target made of carbon and boron mixed with a Co/Ni catalyst under N2 atmosphere. High-resolution transmission electron microscopy…
We investigate the magnetotransport properties of a thin graphite wire resting on a silicon oxide substrate. The electric field effect is demonstrated with back and side gate electrodes. We study the conductance fluctuations as a function of gate voltage, magnetic field, and temperature. The phase coherence length ext…
The diffusion of a bulk absorbed gas species out of spherical pebbles is studied analytically, stressing the usefulness of the time integral of the diffusion coefficient for analysis of arbitrary temperature schedule experiments. Highly accurate approximations are introduced where the numeric evaluation of the analyti…
The transition metal-oxygen bond appears prominently throughout chemistry and solid-state physics. Many materials, from biomolecules to ferroelectrics to the components of supernova remnants contain this bond in some form. Many of these materials' properties strongly depend on fine details of the TM-O bond and intrica…
Synchrotron x-ray-diffraction patterns were measured and analyzed for a polycrystalline sample of the room-temperature ferromagnet ${\mathrm{Sr}}_{3.12}{\mathrm{Er}}_{0.88}{\mathrm{Co}}_{4}{\mathrm{O}}_{10.5}$ from $300\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}650\phantom{\rule{0.3em}{0ex}}\mathrm…
We have performed high-resolution inelastic neutron scattering studies on three samples of hydrogenated tetrahydrofuran-water clathrates, containing either H2 at different para/ortho concentrtion, or HD. By a refined analysis of the data, we are able to assign the spectral bands to rotational and center-of-mass transl…
The maximal value of thermal conductivity κ_{max} of the perfect wurzite GaN crystal containing isotopes of natural abundance is estimated. Our upper limit of κ=4800 W/Km at T_{max}=32 K is smaller than calculated by Liu and Balandin κ=6000 W/Km and higher than obtained by Slack et al κ=3750 W/Km. The phenomenological…
Taking into account the electrostrictive coupling between inhomogeneous polarization fluctuations and lattice strains in ferroelectric films, we show that, in heterostructures involving strained epitaxial films and metal electrodes, the single-domain state may remain stable against the transformation into a polydomain…