From Chromic Phenomena: Technological Applications of Colour Chemistry

3.4 High Energy Photoluminescence

Photoluminescence is a term widely applied to the range of phenomena where light emission occurs from a material after energising by photons. In this section of the book the term is specifically applied to the cases where luminescence occurs after the interaction of luminescent materials with narrow band, higher energy ultraviolet radiation, namely in lighting and plasma display panel applications.

3.4.1 Lighting

Luminescent lighting, commonly called fluorescent lighting, has been in regular use for decades since it was first introduced in the 1930s. Its dominance in the illumination of offices, department stores and public spaces arises from the fact that it has a much higher efficiency than incandescent lighting. For instance, a 60 W incandescent light tube generates only 15 lm W ?1 whilst a 40 W luminescent light bulb yields 80 lm W ?1.14

Luminescent light is generated using ultraviolet radiation from a low-pressure mercury discharge, the mercury vapour being present in the noble gas, which fills the tube under low pressure. The emitted radiation consists of 85% at 254 nm and 12% at 185 nm, the remainder being mainly in the visible region. The lamp phosphors, which coat the inside of the tube, convert the 254 nm and 185 nm light into visible light (Figure 3.6). The light emitted must be white light in order to match the ambient natural lighting from the sun. Since the sun is a black body radiator, a terminology has been developed for the lighting...

Products & Services
Air Conditioners
Air conditioners and building air conditioners are used in industrial, process computing, networking, and other spaces where thermal management is important.  Space and spot cooling equipment are used wherever total heat must be controlled or where localized heat sources must be managed.  Many refrigerants are used in air conditioners; CFC-free refrigerants are becoming more prevalent and in fact are required in many applications.
Variable Air Volume (VAV) Units
Variable air volume (VAV) units are manufactured assemblies of air valves and dampers contained in a single enclosure. As HVAC system components, they regulate airflow to a room or zone in response to a thermostat or other signaling device.
HVAC Fans and Blowers
HVAC fans and blowers are used to move air through heating, ventilating, and air conditioning (HVAC) systems. They are an integral part of the air handling systems that bring or draw fresh air into buildings.
Aftercoolers are heat exchangers for cooling the discharge from a compressor.
Chilled Beams
Chilled Beams are a type of convection HVAC system that are used to heat or cool rooms. Pipes of hot or cold water are passed through the beam. As the beam heats or cools it radiates the warmth or coolness to the surrounding air.

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