Materials Literature
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This book is a comprehensive introduction to the mechanical properties of ceramics, and is designed primarily as a textbook for undergraduate and graduate students in materials science and engineering. Over the past 25 years ceramics have become key materials in the development of many new technologies as scientists h…
Two types of crosslinked polyurethanes (PU) have been synthesized: (a) PU crosslinked by metal ions (Cu2+ and Co2+), and (b) PU crosslinked by the complexes of metals with crown ether. Using X-ray scattering under small and wide angles the peculiarities of the structure of networks have been investigated. It was found…
The electronic energy-band structure for ${\mathrm{RbLaNb}}_{2}{\mathrm{O}}_{7},$ which is closely related to the layered perovskite niobate superconducting ${\mathrm{KCa}}_{2}{\mathrm{Nb}}_{3}{\mathrm{O}}_{10}$ and metallic ${\mathrm{KLaNb}}_{2}{\mathrm{O}}_{7}$ with Li intercalation, has been calculated by using the…
The temperature dependence of the Soret band of various metal-octaethylporphyrins [i.e., Ni(II), Cu(II), and Pd(II)] dissolved in the glass-forming mixture 50% (v/v) isopentane/ethyl ether in the temperature range 300−40 K was studied. Co(II)-octaethylporphyrin dissolved in dichloromethane was also investigated in the…
Attempts have been made to synthesize polyphosphazenes with pendent tertiary amino side units via macromolecular substitution. Incorporation of −OCH 2 CH 2 N(CH 3 ) 2, −OCH 2 CH 2 OCH 2 CH 2 N(CH 3 ) 2, and −NHCH 2 CH 2 N(CH 3 ) 2 groups was studied. Polymers in which all the side groups consisted of one type of aliph…
The response to plate impact loading of three aluminas with varying glass content and porosity has been investigated. Spall strengths have been shown to be dependent on the amplitude and duration of the compression pulse which precedes the tensile loading, but insensitive to the rate of release. Some tensile strength…
The ionic conductivity of glassy, fast-ion-conducting materials can show non-Arrhenius behavior and approach saturation at sufficiently high temperatures [J. Kincs and S. W. Martin, Phys. Rev. Lett. 76, 20 (1996)]. The Ngai coupling model was soon applied to explain some of these observations [K. L. Ngai and A. K. Riz…
The results of an infrared spectroscopic characterization of poly(vinyl cinnamate) (PVCIN) and its blends with poly(4-vinyl phenol) (PVPh) are reported before and after photo-crosslinking the PVCIN by exposure to UV radiation. The purpose of this article is to demonstrate methodology, and it is shown that quantitative…
Photoacoustic and Raman spectroscopy as well as photoluminescence (PL) measurements have been used to investigate the effect of band-gap widening in porous GaP. A correlation between a blueshift of the absorption edge observed during photoacoustic measurements, accompanied by PL emissions in the blue and ultraviolet r…
The electronic structure and properties of ferromagnetic mixed–valence manganites with the perovskite structure are briefly reviewed. The importance of disorder–induced localization is emphasized, and it is proposed magnetic disorder is effective in this sense on three different length scales. First, spin disorder on…
Doping of the Mn-site in Ln1-yAyMn1–xMxO3 manganites has been extensively investigated. For the manganites exhibiting a Curie temperature (Tc) these substitutions depress Tc. However, the effect on Tc is doping–element dependent. It decreases from dTc/dx = –25 K %–1 for M = Fe down to dTc/dx∼0 K %–1 for M = Cr in the…
We report on a type of Si interband transitions at ${\mathrm{Si}(100)\ensuremath{-}\mathrm{S}\mathrm{i}\mathrm{O}}_{2}$ interfaces that has no equivalent in the bulk of crystalline silicon. These transitions, leading to strong resonances in optical second-harmonic-generation spectra with energies of 3.6--3.8 eV, are e…
Colloidal Ag suspensions including adsorbed pefloxacin, an antibacterial agent, were studied by photon correlation spectroscopy (PCS), ζ potential measurements, UV−vis absorption, and surface enhanced Raman scattering (SERS). These techniques provide complementary information about the particle size and state of aggre…
Using a self-consistent linear combination of atomic orbitals method based on density-functional theory in a local-density approximation, the electronic structure in the high-temperature ceramics $\ensuremath{\alpha}\ensuremath{-}{\mathrm{Si}}_{3}{\mathrm{N}}_{4}$ and $\ensuremath{\beta}\ensuremath{-}{\mathrm{Si}}_{3}…
An extended set of temperature-dependent ARUPS data from Ni(111) is presented. The ferromagnetic and the paramagnetic state as well as the phase transition are examined in great detail. Rather new and unconventional modes of data acquisition in ARUPS are applied with high angular and energy resolution, exhibiting grea…
Neutron diffraction techniques have been used to investigate the influence of applied magnetic field and pressure on the structural and magnetic phase transitions in La1–xSrxMnO3. The structural, magnetic and electronic properties are found to be strongly coupled. For suitable compositions the coupling between the mag…
Field-emission current from chemical vapor deposited diamond film on molybdenum wafer has been investigated experimentally and theoretically. The Fowler–Nordheim plot exhibits three linear regimes, corresponding to low, middle, and high electric field, respectively. A potential barrier model, based on a fact that meta…
Excited states of singlet and triplet H2Ti(μ−H)2TiH2 have been calculated using multiconfigurational wave functions. The effects of orbital relaxation are determined by optimizing orbitals for all states separately and comparing to state-averaged calculations, and are found to be small. Dynamic electron correlation in…
The electronic states of a series of ${(\mathrm{D}\mathrm{M}\mathrm{e}\ensuremath{-}\mathrm{D}\mathrm{C}\mathrm{N}\mathrm{Q}\mathrm{I})}_{2}\mathrm{Cu}$ systems with nondeuterated and partially deuterated methyl groups in a DMe-DCNQI molecule have been investigated by ${}^{13}\mathrm{C}$ NMR measurements at the cyano…
Two families of perovskites, LaMnO3+δ and R1–xMnO3–δ (R = La, Pr, Nd) have been prepared in polycrystalline form by a soft–chemistry route. The precursors were annealed at moderate temperatures either in air or under high oxygen pressure. In the strongly oxygenated LaMnO3+δ pervoskites (with nominal Mn4+ contents up t…