Search results
Results from the WOW.Com Content Network
Light: When quicklime is heated to 2,400 °C (4,350 °F), it emits an intense glow. This form of illumination is known as a limelight, and was used broadly in theatrical productions before the invention of electric lighting. [14] Cement: Calcium oxide is a key ingredient for the process of making cement. As a cheap and widely available alkali.
Limelight (also known as Drummond light or calcium light) [1] is a non-electric type of stage lighting that was once used in theatres and music halls. An intense illumination is created when a flame fed by oxygen and hydrogen is directed at a cylinder of quicklime (calcium oxide), [2] due to a combination of incandescence and candoluminescence ...
This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms.It is intended as introductory material for novices; for more specific and technical definitions from sub-disciplines and related fields, see Glossary of cell biology, Glossary of genetics, Glossary of evolutionary biology, Glossary of ecology ...
[1] [2] The most commonly used fluxing oxides in a ceramic glaze contain lead, sodium, potassium, lithium, calcium, magnesium, barium, zinc, strontium, and manganese. These are introduced to the raw glaze as compounds, for example lead as lead oxide. Boron is considered by many to be a glass former rather than a flux.
where E is the energy of the quantum , f is the frequency of the light wave, h is the Planck constant, λ is the wavelength and c is the speed of light. The relationships between the energies of the various quantum states are treated by atomic orbital, molecular orbital, Ligand Field Theory and Crystal Field Theory.
Carbide lighting was inexpensive, but was prone to gas leaks and explosions. Early models of the automobile, car, motorbike and bicycle used carbide lamps as headlamps . Acetylene gas, derived from carbide, enabled early automobiles to drive safely at night.
Calcium oxide is a crucial ingredient in modern cement, and is also used as a chemical flux in smelting. Industrial calcination generally emits carbon dioxide (CO 2 ). A calciner is a steel cylinder that rotates inside a heated furnace and performs indirect high-temperature processing (550–1150 °C, or 1000–2100 °F) within a controlled ...
The US Institute of Medicine (IOM) established Recommended Dietary Allowances (RDAs) for calcium in 1997 and updated those values in 2011. [6] See table. The European Food Safety Authority (EFSA) uses the term Population Reference Intake (PRIs) instead of RDAs and sets slightly different numbers: ages 4–10 800 mg, ages 11–17 1150 mg, ages 18–24 1000 mg, and >25 years 950 mg. [10]