Materials Literature
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Electron spin resonance (ESR) measurements were performed on nitrogen-free diamond films grown by chemical vapor deposition and on diamond single crystals, irradiated by ${}^{17}\mathrm{O}$ ions and annealed in the temperature range $100--1400\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}.$ For those annealed in the ra…
An amorphous $2\mathrm{CdO}\ensuremath{\cdot}{\mathrm{GeO}}_{2}$ thin film with a band gap of 3.4 eV can be converted from an insulator (conductivity $\ensuremath{\sim}{10}^{\ensuremath{-}9}{\mathrm{S}\mathrm{}\mathrm{cm}}^{\ensuremath{-}1})$ into a degenerate semiconductor $(\ensuremath{\sim}{10}^{2}{\mathrm{S}\mathr…
A large number of new liquid crystals incorporating the 2,5-disubstituted thiophene ring have been prepared and their mesomorphic behaviour studied in order to systematically investigate the correlation between the molecular structure and mesomorphism of thiophene derivatives with different shapes, polarisability and…
Thermoplastic vulcanizates (TPVs), as prepared by dynamic vulcanization, are blends in which cross-linked rubber particles are finely dispersed in a thermoplastic matrix. The reported nylon-6/EPDM TPVs show significant strain recovery behavior, even though the matrix consists of semicrystalline nylon-6, which deforms…
Synthesis of a cubic ethane−silica hybrid organic−inorganic mesoporous material using a binary surfactant mixture is reported. The system consists of ethane-bridged organosilica (BTME), polyoxyethylene alkyl ether [C 12 (EO) 4; Brij 30], and the octadecyltrimethylammonium chloride (C 18 TMACl) surfactants in a basic m…
The use of a quinone functionality in the linkage unit of laterally bridged oligoporphyrins as a switch for controlling electronic coupling between the termini is examined. The quinone-bridged bisporphyrin P(2)TA-O(2) was synthesized by condensation of 2 equiv of the dione 2,3-dioxo-5,10,15,20-tetrakis(3,5-di-tert-but…
A polyalkynylene-based conducting polymer (molecular wire) has been synthesized within the Cu-functionalized mesoporous MCM-41 silica catalyst. Fluorescence and 13C solid-state NMR provided spectroscopic evidence that the synthesis of extended polymeric chains with a high degree of alignment requires homogeneously dis…
Gold clusters on the surface of MgO powder (calcined at 673 K) were prepared from adsorbed [Au(CH 3 ) 2 (acac), where acac is C 5 H 7 O 2 ] and characterized by extended X-ray absorption fine structure (EXAFS) spectroscopy and X-ray absorption near edge spectroscopy (XANES). One sample initially contained gold predomi…
Electron conduction through quasi-one-dimensional (1D) indium atomic wires on silicon (the Si(111)-4x1-In reconstruction) is clarified with the help of local structural analysis using scanning tunneling microscopy. The reconstruction has a conductance per square as high as 100 uS, with global conduction despite numero…
We study the extreme long-time behavior of the metastable phase of the three-dimensional Ising model with Glauber dynamics in an applied magnetic field and at a temperature below the critical temperature. For these simulations we use the advanced simulation method of projective dynamics. The algorithm is described in…
We have studied the binding energies and electronic structures of metal (Ti, Al, Au) chains adsorbed on single-wall carbon nanotubes (SWNT) using first-principles methods. Our calculations have shown that titanium is much more favored energetically over gold and aluminum to form a continuous chain on a variety of SWNT…
While both La$_{0.7}$Sr$_{0.3}$MnO$_3$ and La$_{0.7}$Sr$_{0.3}$CoO$_3$ are ferromagnets with metallic conductivity below $T_\mathrm{c}$ (360K and 220K, respectively), partial substitutions of Co by Mn in La$_{0.7}$Sr$_{0.3}$Co$_{1-y}$Mn$_y$O$_3$ ($y < 0.1$) drastically suppress the ferromagnetic long-range order pre-e…
A microscopic model is developed considering randomly oriented polar regions stuck to the directions of random fields or stresses. The application of an external field (stress) in this model results in a dielectric and acoustic reply connected with a polarization (strain) rotation. Polarization (strain) fluctuation co…
It is shown that Coulomb series are to be considered within a special mode of summation so as to describe bulk properties of crystals. The translational invariance is then an explicit integral property of Coulomb series that is tantamount to the effect of invariant periodic boundary conditions discussed earlier. Absol…
An in vivo rat cage implant system was used to identify potential surface chemistries that prevent failure of implanted biomedical devices and prostheses by limiting monocyte adhesion and macrophage fusion into foreign-body giant cells while inducing adherent-macrophage apoptosis. Hydrophobic, hydrophilic, anionic, an…
We have successfully fabricated highly (up to 6%) Mn-doped bulk Ge single crystals. The lattice constant increases linearly with Mn concentration due to the larger Mn atomic radius compared with Ge, strongly indicating that Mn ions are being incorporated into the host Ge lattice. Alloys with lower Mn concentrations sh…
Nanotube/nanoparticle hybrid structures are prepared by forming Au and Pt nanoparticles on the sidewalls of single-walled carbon nanotubes. Reducing agent or catalyst-free electroless deposition, which purely utilizes the redox potential difference between Au3+, Pt2+, and the carbon nanotube, is the main driving force…
The linear absorption cross section is a crucial parameter to the design of nanocrystal quantum dot devices and to the interpretation of spectroscopic data. We measure and report the size-dependent absorption cross section of CdSe nanocrystal quantum dots. We compare the results for absorption far above the band edge,…
The layer structure of 4-octyl-4 ' -cyanobiphenyl (8CB) liquid crystalline free-standing films (FSFs) was studied. By transmission ellipsometry using a photoelastic modulator (PEM), the incidence angle dependence of the phase difference was measured with high resolution. The theoretical characteristics in the smectic…
The deposition of TiO 2 films on InP substrate is studied by liquid phase deposition (LPD) with H 2 TiF 6 and H 3 BO 3 as the starting materials at the growth temperature of 75°C. The growth rate of TiO 2 is about 42 Å/min. The surface morphology of the TiO 2 films was mirror-like. The film stoichiometry was measured…