Tungsten lamp halide

Lamp types (a) incandescent and tungsten-halogen lamp shapes (b) fluorescent and compact fluorescent lamp shapes (c) typical high-pressure sodium lamp (d) typical metal halide lamp. 

There are many varieties of metal halide lamps, the most familiar being the tungsten-halide lamps found in many homes, or the sodium and mercury vapor lamps found on streets and in auditoriums, convention centers and large space commercial buildings. Many have seen the change in color given off as these lamps warm up to their operating temperature. 

Many other types of light sources can also be used for photopolymerization reactions, for example, low-pressure mercury arcs, flash lamps, fluorescent lamps, tungsten halide sources, and even lasers. A complete review of light sources used in photopolymerization reactions can be found in Reference 18,... 

The SiOx films we fabricated was done by physical vapor deposition of SiO with controlled oxygen admission in an oil-free vacuum apparatus at 1 x 10 mbar base pressure. The experimental set-up is shown schematically in Figure 19.4. Thermal evaporation of SiO from two Ta boats was directed to rotating 10 cm Si(lOO) wafer substrates heated by rear illumination with tungsten halide lamps. To achieve uniform film thickness over the large area of the Si wafer, the angle between the evaporators and substrate center was fixed at 53°, while the distance between the substrate plane and evaporator plane was kept at 20 cm. Routinely, films of 100 run... 

In arc lamps, the emission is obtained by the activation of a gas by collision with accelerated electrons generated by an electric discharge between two electrodes, typically tungsten-made. The type of lamp is often denoted by the gas contained in the bulb including neon, argon, xenon, krypton, sodium, metal halide and mercury. In particular, for mercury lamps, the following classification, based on the Hg pressure, is done ... 

Type of lamp Incandescent lamps Tungsten halogen High pressure sodium Metal halide Fluorescent Compact fluorescent Induction... 

As primary sources, continuous sources such as a tungsten halide or a deuterium lamp can be used. They have the advantage that multi-element determinations are possible. However, because of the low radiant densities, saturation is not obtained and the power of detection is not fully exploited. With line sources, such as hollow cathode sources and electrodeless discharge lamps, much higher radiances can be obtained. Even ICPs into which a concentrated solution is introduced can be used as a primary source, through which multi-element determinations become possible. 

Tungsten(II) chloride has been used as a starting material in a variety of organometallic and inorganic syntheses. In addition, there has been interest in its use as a chemical transport agent, such as in incandescent lamps or XeCl excimer lasers, which has resulted in several thermochemical and thermodynamic studies of the metal halide systems. 

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