Materials Literature
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We calculate the isotope and temperature shifts of the indirect and direct band gaps in natural silicon (M\ifmmode\bar\else\textasciimacron\fi{}=28.09 u), in natural diamond $^{12}\mathrm{C}$ and its isotope $^{13}\mathrm{C}$, in natural germanium (M\ifmmode\bar\else\textasciimacron\fi{}=72.59 u), and the isotope $^{7…
We present results of all-electron molecular relativistic (Hartree–Fock–Dirac) and nonrelativistic (Hartree–Fock) calculations followed by a complete open shell configuration interaction (COSCI) calculation on an EuO9−6 cluster in a Ba2GdNbO6 crystal. The results include the calculated energies of a number of states d…
Fe100−xCox powders were prepared by mechanical alloying of the elements in a planetary ball mill. They were investigated with respect to phase formation and magnetic properties using x-ray diffraction, differential scanning calorimetry, and measurements of the saturation magnetization and the coercivity. The measureme…
High-precision, large-basis-set calculations, in the local-density approximation (LDA) (using the all-electron, full-potential, linear combination of Gaussian orbitals, fitting-function technique), of the cohesive properties and electronic states (bare Kohn-Sham energies) of the isolated AB dilayer of graphite are rep…
X-ray-absorption measurements at the Cu ${\mathit{L}}_{2,3}$ and O K edges of ${\mathrm{Cu}}_{2}$O reveal the presence of unoccupied states of predominantly Cu d and O p character at the bottom of the conduction band. We find that spectral features up to 25 eV from threshold can be assigned to structures in the calcul…
It is an open question if ``metallic'' polymers have one-dimensional or three-dimensional conduction states. We investigate this issue by studying a model polymer, the HCl-doped emeraldine salt form of oriented polyaniline (PAN-ES) through the temperature dependence of the dc conductivity, thermoelectric power, comple…
Although crucial to our understanding of skeletal evolution in marine invertebrates, the cost of calcification has remained elusive for a simple reason: CaCO3 is an inorganic material. Its cost thus derives solely from the metabolic expenses of accumulating, transporting, and precipitating CaCO3 and cannot normally be…
We have investigated the tissue distribution, toxicity, and antitumor activity of anthracyclines encapsulated in hydrogenated phosphatidylinositol (HPI)-containing liposomes which show a characteristic long circulation time in plasma (J. Natl. Cancer Inst., 81: 1484-1488, 1989). Phosphatidylglycerol (PG)-containing li…
We follow the cluster formation when depositing less than 2 monolayers Cu onto a monocrystalline αAl 2 O 3 (0001) stoichiometric surface, by combining XPS and X-ray absorption spectroscopy at the Cu K edge (EXAFS, XANES). An estimate of the evolution of cluster size with copper deposition is given from XANES and EXAFS…
Polycrystalline diamond films synthesized by microwave-assisted chemical vapor deposition (MACVD) were examined with transient photoconductivity, and two fundamental electrical transport properties, the carrier mobility and lifetime, were measured. The highest mobility measured is 50 centimeters squared per volt per s…
A binary aqueous suspension of large (L) and small (S) nearly-hard-sphere colloidal polystyrene spheres is shown to segregate spontaneously into L-rich and S-rich regions for suitable choices of volume fraction and size ratio. This is the first observation of such purely entropic phase separation of chemically identic…
We have measured the electrical resistivity of NbSe3 between 2 K and room temperature up to a pressure of 7.2 GPa. At P1 = 3.5 GPa we observe the extinction of the high-temperature charge density wave (T1-CDW) and the enhancement of the superconducting critical temperature Tc to 5 K. The logarithmic pressure slopes of…
Computer simulations of hydrocarbon and related molecules using empirical force fields have become important tools for studying a number of biological and related processes at the atomic scale. Traditional force fields, however, cannot be used to simulate dynamic chemical reactivity that involves changes in atomic hyb…
Liquidus phase relationships have been investigated in the peraluminous system Qz (SiO 2 ) - Ab (NaAlSi 3 O 8 ) - Or (KAlSi 3 O 8 ) - Al 2 O 3 - H 2 O - CO 2 . The experiments have been performed at 2 kbar, 750 to 850°C and at H 2 O-undersaturated conditions (H 2 O-activity close to 0.5). An aluminosilicate phase (mul…
An unusually REE-rich piemontite was found near Colonnata on the northern slope of Monte Brugiana and La Rocchetta, Alpi Apuane, Italy. Quantitative chemical analyses show a total amount of rare earth elements ranging from 2.85 to 8.06 (oxides wt%) with lanthanum prevailing on the others. Structural data obtained on f…
The phase transition and compressibility of Mn 3 O 4 have been investigated at room temperature with X-ray diffraction diamond-anvil cell experiments up to 38.7 GPa. At pressures below 10 GPa a tetragonal phase is present, having the hausmannite structure, whereas at higher pressure the hausmannite phase transforms in…
The effects of simulated transport of calves for 150 min on plasma cortisol, NEFA, glucose, and calcium were evaluated. Both cortisol and NEFA reached maximal values within 30-60 min, with no further increases during the transportation. Changes in glucose and calcium were not significant. The results indicate that in…
Arsenic antisites in GaAs layers grown by molecular-beam epitaxy at low substrate temperatures (∼200 °C) were observed using electron paramagnetic resonance (EPR), magnetic circular dichroism in absorption (MCDA), and MCDA-detected EPR. This observation confirms that there is a MCDA band directly associated with arsen…
This is the third in a series of papers on the ab initio calculation of the third and fourth derivatives of the energy of a molecule. In this paper derivatives with respect to electric field components, as well as with respect to nuclear coordinates are considered. A knowledge of these derivatives yields, in particula…
A high-resolution x-ray study of the nematic--to--smectic ${\mathit{A}}_{1}$ phase transition of 8OPCBOB gives a critical exponent for the susceptibility \ensuremath{\gamma}=1.39\ifmmode\pm\else\textpm\fi{}0.08, and for the parallel correlation length ${\ensuremath{\nu}}_{\mathrm{\ensuremath{\parallel}}}$=0.71\ifmmode…