Tremolite is an amphibole mineral which occurs naturally in three distinct mor­ phological forms or mineral habits. It may occur as asbestos, splintery fibres or in mas­ sive crystalline deposits. Mineral habit is determined at the time of its crystallization and conversion to a different habit would require re-crystallization. The massive crystalline deposits, on crushing may yield elongated f...

In 1903 Hopkins and Cole (1) identified tryptophan as the source of indole produced by bacterial cultures. The tryptophan-inducible enzyme responsible for this conversion, which is found most commonly in Escherichia coli, was subsequently named tryptophanase by Happold and Hoyle (2). Wood, Gunsalus, and Umbreit (3) showed that tryptophanase catalyzed the stoichiometric conversion of tryptophan ...

quasicrystals are a group of materials with the quasi-periodic structure, and since their discovery in 1980 their specially interesting physical properties have attracted the attention of many researchers. the lack of translational periodicity makes the numerical calculations of their physical properties much more difficult than the crystalline solids. in this work we present a detailed numeric...

the improvement of the physical properties of indium tin oxide (ito) layers is quite advantageous in photovoltaic applications. in this study the ito film is deposited by rf sputtering onto p-type crystalline silicon (c-si) with (100) orientation, multicrystalline silicon (mc-si), and glass substrates coated with zno and annealed in vacuum furnace at 400°c. electrical, optical, structural and m...