Interactions of Hyperthermal TiClx+ (x = 0−4) Ions with Graphite Surfaces

Reactive collisions of hyperthermal energy molecular ions with solid surfaces

Recent experimental advances have uncovered many of the diverse reaction pathways following an energetic collision between a molecular ion and a solid surface. Hyperthermal translational energies (5-500 eV) are sufficient to activate a number of chemical transformations in the near-surface region, including charge transfer, dissociation, abstraction, and deposition. State-of-the-art scattering studies probe the consumption and disposal of energy and the effects of approach geometry and surface electronic structure on the operative reaction mechanisms. These fundamental investigations provide insight relevant to the fabrication of microelectronics devices, the interaction of space vehicles with the earth's atmosphere, and the development of analytical techniques in mass spectrometry.

Preparation and analysis of macroporous TiO2 films on Ti surfaces for bone-tissue implants

This article describes the preparation and analysis of macroporous TiO2 films on Ti surfaces, for application in bone tissue-Ti implant interfaces. These TiO2 bioceramic films have a macroporous structure consisting of monodisperse, three-dimensional, spherical, interconnected pores adjustable in the micron size range. Micron-sized polystyrene (PS) bead templates are used to precisely define the pore size, creating macroporous TiO2 films with 0.50, 16, and 50 microm diameter pores, as shown by scanning electron microscopy. X-ray photoelectron spectroscopy shows the films to be predominantly composed of TiO2, with approximately 10% carbon. X-ray diffraction reveal rutile as the main phase when fired to the optimal temperature of 950 degrees C. Preliminary experiments find that the in vitro proliferation of human bone-derived cells (HBDC) is similar on all three pore sizes. However, higher [3H]thymidine incorporation by the HBDC is observed when they are grown on 0.50- and 16-microm pores compared to the 50-microm pores, suggesting an enhanced cell proliferation for the smaller pores.