Analysis of Fuel Vapor Characteristics in an Aircraft Fuel Tank Ullage.

As a prerequisite to a comprehensive analysis of aircraft fuel tank fire and explosion hazards, a vapor-liquid equilibrium thermodynamic analysis was developed to assess the fuel vapor behavior in an aircraft fuel tank ullage. The analysis was based on the Peng-Robinson equation of state and the extended corresponding-states method. Jet-A fuel was treated as a pseudo single-component fluid. The calculated fuel/air mass ratios followed the trend observed in previous measurements.

Analysis Of Phosphorus In Chemical Vapor Deposited Films For Semiconductor Device Fabrication

A semiconductor is a crystalline material having a conductivity between that of a conductor and an insulator. The conductivity of semiconductors can be varied by changes in temperature, optical excitation, and impurity content. This variability of electrical properties makes the semiconductor material of elementary crystalline silicon an ideal material for electronic device fabrication. Silicon has the ability of undergoing a large variety of processing steps without the problems of decomposition. One such process involved in fabrication is the chemical vapor deposition of silicon dioxide films on the silicon. Chemical vapor deposition (CVD) can be defined as a material synthesis method in which the constituents of the vapor phase react to form a solid film at the surface of a silicon wafer. Dielectric layers such as the deposited silicon dioxide, and phosphorus doped oxides, silicon dioxide rich with phosphorus pentoxide, are used in semiconductor device fabrication for the insulation between conducting layers, for diffusion and ion implantation masks, and for passification to protect devices from impurities, scratches, and moisture.