Materials Literature
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The time of flight technique is used to study experimentally the charge-carrier transport in porous silicon. The measured drift mobilities of electrons and holes show a decrease with the reduction of the typical size of structural elements of the porous material. The experimental transient characteristics reveal a str…
Single crystals of 1% ${\mathrm{Er}}^{3+}$-doped ${\mathrm{Cs}}_{3}{\mathrm{Lu}}_{2}{\mathrm{Cl}}_{9}$ were grown using the Bridgman technique. From highly resolved polarized absorption spectra measured at 10 and 16 K, and upconversion luminescence and excitation spectra measured at 4.2 K, 114 crystal-field levels fro…
The Raman scattering spectra of amorphous porous silicon are investigated. It is found that the so-called boson peak in the acoustical part of the Raman spectra is more sensitive to the degree of structural disorder than the optical mode, which is normally used to determine the latter. This can be explained by the fac…
The synthesis and magnetic and magnetoelastic properties of PrxTb1−xFe2 and Pr0.15TbxDy0.85−xFe2 are reported. The study on the crystalline structure, magnetization, and Curie temperature shows that PrFe2 has a lattice parameter of 7.463 Å and a magnetic moment of 4.93 μB/f.u. With the addition of Pr, the anisotropy o…
Adiabatic potentials, energy levels and wavefunctions for collective vibrational states of hydrogen isotopes in monohydrides of transition metals with face-centred cubic lattices, and NiH, and with body-centred cubic lattices, and CrH, are investigated by means of ab initio total-energy calculations in the local densi…
The Lyman spectrum of substitutional boron acceptors in diamonds with natural composition and that in a ${}^{13}\mathrm{C}$ diamond exhibit remarkably similar features, but shifted to higher energies in the latter by 0.4--1.5 meV. Additional lines appear when the spectra are recorded as a function of temperature, indi…
Electron energy loss spectroscopy in a high-resolution transmission electron microscope has recently been used with success to characterize the electronic properties of closed cage nanometer-size graphitic particles. In the plasmon region, the experimental data reveal interesting size-dependent variations, which are n…
For the heteroepitaxial deposition of diamond on silicon using the bias-enhanced nucleation procedure, several different processes contributing to the final misalignment of the layers can be identified: (i) The interface of Si/diamond or Si/SiC and SiC/diamond, respectively. (ii) The growth of individual grains during…
The role of protein and cellular components of thrombi in mediating bacterial adhesion on artificial surfaces was investigated in this study. The attachment of Staphylococcus aureus on polyurethane surfaces was observed directly using an automated video microscopy system. Surfaces were preconditioned with components o…
Transport measurements under pressure and magnetic field on low-doped ${\mathrm{La}}_{0.9}{\mathrm{Sr}}_{0.1}{\mathrm{MnO}}_{3}$ single crystals have clearly evidenced the stabilization of the low-temperature charge ordered state when increasing pressure and field. The observation of a pronounced change of magnetizati…
Magnetoresistance properties of compounds with the same formula La0.7−xGdxCa0.3MnO3+δ (x=0, 0.04) but synthesized by the solid-state reaction method from different starting materials are studied. Nearly stoichiometric compounds are obtained when La(OH)3 is used for sample preparation. However, under the same condition…
The initial attachment reaction of most cultured cell types to polymers is based on a linkage of integrin receptors to serum-derived fibronectin and vitronectin that adsorb onto the polymer surface. Recently isolated corneal epithelial cells have an additional attachment mechanism, known to operate on tissue culture p…
Dielectric measurements at very low temperature indicate that in the multicomponent glass $\mathrm{BaO}\ensuremath{-}{\mathrm{Al}}_{2}{\mathrm{O}}_{3}\ensuremath{-}{\mathrm{SiO}}_{2}$ a phase transition occurs at 5.84 mK. Below that temperature small magnetic fields of the order of $10\ensuremath{\mu}\mathrm{T}$ cause…
Ultraviolet–photon absorption constants were measured for thin CsI, KI, RbI, NaI and CsBr evaporated films, in the 140–200 nm spectral range. The constant measured for CsI is consistent with literature data; the absorption data for the other materials are given here for the first time. The absorption lengths for all m…
In this paper, we report first-principles structural models of surfaces of tetrahedral amorphous carbon $(ta\ensuremath{-}\mathrm{C})$. The topology and defect structure of the amorphous surfaces are analyzed at the atomistic level. We examine the transition of the local bonding environment from the bulk to the surfac…
PbZrO 3 is an antiferroelectric perovskite with TC≈230 °C. We have deposited single phase, perfectly c-axis oriented thin films of PbZrO3 on Si(100) substrates by pulsed laser ablation at 700 °C. The growth conditions (substrate temperature, ambient oxygen pressure, and laser energy density) have been optimized and th…
The random sequential adsorption (RSA) approach was used to analyze adsorption of hard spheres at surfaces precovered with smaller sized particles. Numerical simulations were performed to determine the available surface function φl of larger particles for various particle size ratios λ=al/as and surface concentration…
The energetical ordering and magnetic states of hexagonal and double-hexagonal close-packed (hcp, dhcp) as well as face-centred cubic (fcc) Fe and FeH crystals are studied via spin-polarized ab initio total-energy calculations in the local spin-density approximation and with generalized gradient corrections by means o…
The relation between rheological properties and phase-separated structures of polymer blend solutions is investigated by using the shear microscopy method to obtain insight into the mechanism of steady state formation under shear flow. The time dependence of viscosity and morphology is observed after a stepwise increa…
Using scanning-probe-microscopy techniques, we have measured dielectric relaxation on ultrasmall, mesoscopic, length scales in a glassy polymer (polyvinyl acetate) film near its glass transition. The effective length scale sampled by these techniques is \ensuremath{\sim}50 nm. This is large enough to probe subsurface…