Titanium dioxide has been a favored high index material by some, but it appears to be less popular with others because of difficulties in obtaining a stable result. We discuss what we think is the root of the problem and how it may be rectified. The need to have negligible absorption places a lower limit on the background oxygen pressure and some constraints on temperature and deposition rate. ...

Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a source of single-node stem cuttings. The structure of native starch in tubers formed on cuttings was determined using methods of X-ray scattering and differential scanning microcalorime...

Empirical studies of zircon in migmatites document features compatible with growth during heating at suprasolidus conditions. However, numerical modelling behaviour suggests that is expected to grow only cooling and melt crystallization. Here, phase equilibrium coupled mineral–melt Zr partitioning used an attempt reconcile the observations from predictions previous models anatectic systems. In ...

Introduction Information about the physical properties of materials at high pressures and temperatures is important for advancing our understanding of planetary interiors. Determining the melting curves of materials has attracted much interest in the planetary sciences. For example, the pressure dependencies of the melting curve and viscosity have been linked [1]. Furthermore, the accurate dete...

Cu–Cr-Zr alloys had wide applications in engineering applications such as electrical and welding industrial especially for their high strength, high electrical as well as acceptable thermal conductivities and melting points. It was possible to prepare the nano-structure of these age hardenable alloys using mechanical alloying method as a cheap and mass production technique to prepare the non-eq...

Elucidating the mechanism of folding of polynucleotides depends on accurate estimates of free energy surfaces and a quantitative description of the kinetics of structure formation. Here, the kinetics of hairpin formation in single-stranded DNA are measured after a laser temperature jump. The kinetics are modeled as configurational diffusion on a free energy surface obtained from a statistical m...

A novel type II nucleoside 2'-deoxyribosyltransferase from Lactobacillus reuteri (LrNDT) has been cloned and overexpressed in Escherichia coli. The recombinant LrNDT has been structural and functionally characterized. Sedimentation equilibrium analysis revealed a homohexameric molecule of 114 kDa. Circular dichroism studies have showed a secondary structure containing 55% alpha-helix, 10% beta-...

Solid-state phase transformations and melting of high-purity crystalline boron have been in situ and ex situ studied at pressures to 20 GPa in the 1500-2500 K temperature range where diffusion processes become fast and lead to formation of thermodynamically stable phases. The equilibrium phase diagram of boron has been constructed based on thermodynamic analysis of experimental and literature d...

We report large scale Monte Carlo simulations of the equilibrium discrete Laplacian roughening (dLr) model, originally introduced as the simplest one accommodating the hexatic phase in two-dimensional melting. The dLr model is also relevant to surface roughening in molecular beam epitaxy (MBE). Our data suggest a single phase transition, possibly of the Kosterlitz-Thouless type, between a flat ...

We carry out extensive Monte Carlo simulations of the three-dimensional uniformly frustrated XY model with uncorrelated randomly perturbed couplings, as a model for the equilibrium behavior of an extreme type-II superconductor with quenched uncorrelated random point vortex pinning, in the presence of a uniform applied magnetic field. We map out the resulting phase diagram as a function of tempe...