The sodium vapor process (occasionally referred to as yellowscreen) is a photochemical film technique for combining actors and background footage. It originated in the British film industry in the late 1950s and was used extensively by Walt Disney Productions in the 1960s and 1970s as an alternative to the more common bluescreen process. Wadsworth E. Pohl is credited with the invention or development of both of these processes (Patent US3133814A), and received (with Ub Iwerks and Petro Vlahos) an Academy Award in 1965 for the sodium vapor process used in the film Mary Poppins. Description The process is not very complicated in principle. An actor is filmed performing in front of a white screen that is lit with powerful sodium vapor lights. Such light has a narrow color spectrum that falls neatly into a chromatic notch between the various color sensitivity layers of the film, so the odd yellow color does not register on the red, green, or blue layers. This allows the complete range of colors to be used, not only in costumes, but also in makeup and props. A camera with a beam-splitter prism is used to expose two separate...

A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm. Two varieties of such lamps exist: low pressure and high pressure. Low-pressure sodium lamps are highly efficient electrical light sources, but their yellow light restricts applications to outdoor lighting, such as street lamps, where they are widely used. High-pressure sodium lamps emit a broader spectrum of light than the low-pressure lamps, but they still have poorer color rendering than other types of lamps. Low-pressure sodium lamps only give monochromatic yellow light and so inhibit color vision at night. Single ended self-starting lamps are insulated with a mica disc and contained in a borosilicate glass gas discharge tube (arc tube) and a metal cap. They include the sodium-vapor lamp that is the gas-discharge lamp in street lighting. Development The low-pressure sodium arc discharge lamp was first made practical around 1920 owing to the development of a type of glass that could resist the corrosive effects of sodium vapor. These operated at pressures...

Read chapter 4 Potassium: Dietary Reference Intakes for Adequacy: As essential nutrients, sodium and potassium contribute to the fundamentals of physiolog...

Fact sheet on sodium reduction: key facts, overview, recommendations, actions and WHO response.

Multiple unite sustained released floating of sodium diclofenac: Formulation and evaluation using factorial design

Sodium fluoride (NaF) is an inorganic compound with the formula NaF. It is a colorless or white solid that is readily soluble in water. It is used in trace amounts in the fluoridation of drinking water to prevent tooth decay, and in toothpastes and topical pharmaceuticals for the same purpose. In 2020, it was the 265th most commonly prescribed medication in the United States, with more than 1 million prescriptions. It is also used in metallurgy and in medical imaging. Uses Dental caries Fluoride salts are often added to municipal drinking water (as well as to certain food products in some countries) for the purpose of maintaining dental health. The fluoride enhances the strength of teeth by the formation of fluorapatite, a naturally occurring component of tooth enamel. Although sodium fluoride is used to fluoridate water and is the standard by which other water-fluoridation compounds are gauged, hexafluorosilicic acid (H2SiF6) and its salt sodium hexafluorosilicate (Na2SiF6) are more commonly used additives in the...

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