Heat treatment and stress state effects on the martensitic transformation in [001] and [123] oriented single crystal Ni54Fe19Ga27 alloys are determined. Characteristic temperatures increase for longer aging times and higher hold temperatures. The non-aged [001] crystals exhibit the smallest stress hysteresis and lowest critical stress in tension. The experimental results are interpreted based o...

A method based on the kinetics of crystal growth has been developed and applied to the computation of three-dimensional microstrucuture in austenite-matensite steels. The detailed crystallography of the transformation is used to model a realistic martensitic microstrucuture during the transformation without an external system of stresses. The interaction energy based on the plastic work model i...

We investigated experimentally and theoretically an invertible fiber-type transformation from a photonic bandgap fiber into a nonideal waveguide and then into an index-guiding photonic crystal fiber via the thermo-optic effect of the fluid filled in the air holes. Such a transformation could be used to develop an in-fiber optical switch/attenuator with a high-extinction ratio of more than 35 dB...

This paper focuses on the symmetries of space lattice crystal cells. All 32 point groups of three dimensional crystal cells are exclusively described by vectors (three for one particular cell) taken from the physical cell. Geometric multiplication of these vectors completely generates all symmetries, including reflections, rotations, inversions, rotary-reflections and rotary-inversions. The set...

Benjamin Gilbert, Hengzhong Zhang, Feng Huang, Michael P. Finnegan, Glenn A. Waychunas and Jillian F. Banfield* Department of Earth and Planetary Sciences, University of California, Berkeley, Berkeley, CA 94720, USA. E-mail: [email protected]; Fax: 11 510 643 9980; Tel: 11 510 643 9120 Materials Science Program, University of Wisconsin Madison, 1509 University Avenue, Madison, WI 53706-...

A simple model of the closely packed structure for system of hard-sphere particles interacting via the long-range Newtonian type attraction is suggested. Based on density functional theory, the exact equation of state is obtained and the mutual transformations of the crystal structures in such systems are studied. The description takes into account the fact impossibility of hard-sphere particle...

Optical birefringence and x-ray measurements are reported for single crystals (0.5 mm X 2 mm X 5 micrometers) of dipalmitoylphosphatidylcholine as a function of temperature and relative humidity. Large single crystals grown in CHCl3/acetone at a low water concentration undergo an irreversible phase transformation at 20 degrees C and 70% relative humidity or at 60 degrees C and 65% relative humi...

A new and efficient algorithm is presented for the coordinate transformation problem of massively three-dimensional networks formed, e.g., by the atoms of crystal fragments or molecular clusters. The new algorithm is based on a divide-and-conquer technique to perform iterative coordinate transformation, applicable even for three-dimensional networks, with linear scaling memory and near linear s...

A new material containing macroscopic quantities of onion-like carbon (OLC) particles is produced by heat treatment of ultra-disperse diamond (UDD) powder (2-6 nm). Annealing products (characterized by high-resolution electron microscopy) are presented by: (a) quasi-spherical particles with closed concentric graphite shells, (b ) polyhedron particles with closed shells, (c) elongated particles ...