This paper explores the physical mechanisms responsible for experimental observations that led to the definition of ‘‘photo-induced hydrogen outgassing of glass’’. Doped borosilicate glass samples were placed inside an evacuated silica tube and heated in a furnace or by an incandescent lamp. It was observed that hydrogen release from the glass sample was faster and stronger when heated by an in...

The use of carbon and tungsten filaments mounted in vacuum as early incandescent lamps is well-known, but it is less often realised that an early competitor was Nernst’s ceramic lamp. This made use of the property that , although good insulators at room temperature, many oxides become partially conductive when strongly heated. This is due to the migration of ions rather than electrons, and was ...

INTRODUCTION Accident data for 2003-2007 indicate that slip, trip, and falls (STFs) are the second leading accident class (17.8%, n=2,441) of lost-time injuries in underground mining. Proper lighting plays a critical role in enabling miners to detect STF hazards in this environment. Often, the only lighting available to the miner is from a cap lamp worn on the miner's helmet. The focus of this ...

This paper discusses the design and implementation of single phase PWM inverter using 8051 microcontroller. The main features of 8051 based PWM inverter are simpler design, low cost, maximum range of voltage control and compact in size. The designed PWM inverter is tested on various AC loads like AC motor and intensity control of incandescent lamp in a closed loop environment.