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Globar
{{Unreferenced, date=January 2023 A Globar is used as a thermal light source for infrared spectroscopy. The preferred material for making Globar is silicon carbide that is shaped as rods or arches of various sizes. When inserted into a circuit that provides it with electric current, it emits radiation from ~ 2 to 50 micrometres wavelength via the Joule heating phenomenon. Globars are used as infrared sources for spectroscopy because their spectral behavior corresponds approximately to that of a Planck radiator (i.e. a black body). Alternative infrared sources are Nernst lamps, coils of chrome–nickel alloy or high-pressure mercury lamps. The technical term ''Globar'' is an English portmanteau word consisting of ''glow'' and ''bar''. The term ''glowbar'' is sometimes used synonymously in English (which is an incorrect spelling in the strict sense). The ''American Resistor Company'' in Milwaukee, Wisconsin, had word and lettering ''Globar'' registered as a trademark (in a special ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nernst Lamp
The Nernst lamp was an early form of incandescent lamp. Construction Nernst lamps did not use a glowing tungsten filament. Instead, they used a ceramic rod that was heated to incandescence. Because the rod (unlike tungsten wire) would not further oxidize when exposed to air, there was no need to enclose it within a vacuum or noble gas environment; the burners in Nernst lamps could operate exposed to the air and were only enclosed in glass to isolate the hot incandescent emitter from its environment. A ceramic of zirconium oxide – yttrium oxide was used as the glowing rod. Efficiency Developed by the German physicist and chemist Walther Nernst in 1897 at the University of Göttingen, these lamps were about twice as efficient as carbon-filament lamps and emitted a more "natural" light (more similar in spectrum to daylight). The lamps were quite successfully marketed for a time, although they eventually lost out to the more efficient tungsten-filament incandescent li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicon Carbide
Silicon carbide (SiC), also known as carborundum (), is a hard chemical compound containing silicon and carbon. A wide bandgap semiconductor, it occurs in nature as the extremely rare mineral moissanite, but has been mass-produced as a powder and crystal since 1893 for use as an abrasive. Grains of silicon carbide can be bonded together by sintering to form very hard ceramics that are widely used in applications requiring high endurance, such as car brakes, car clutches and ceramic plates in bulletproof vests. Large single crystals of silicon carbide can be grown by the Lely method and they can be cut into gems known as synthetic moissanite. Electronic applications of silicon carbide such as light-emitting diodes (LEDs) and Cat's whisker detector, detectors in early radios were first demonstrated around 1907. SiC is used in semiconductor electronics devices that operate at high temperatures or high voltages, or both. Natural occurrence Naturally occurring moissanite is found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury-vapor Lamp
A mercury-vapor lamp is a gas-discharge lamp that uses an electric arc through vaporized mercury to produce light. The arc discharge is generally confined to a small fused quartz arc tube mounted within a larger soda lime or borosilicate glass bulb. The outer bulb may be clear or coated with a phosphor; in either case, the outer bulb provides thermal insulation, protection from the ultraviolet radiation the light produces, and a convenient mounting for the fused quartz arc tube. Mercury-vapor lamps are more energy efficient than incandescent lamps with luminous efficacies of 35 to 55 lumens/watt. Their other advantages are a long bulb lifetime in the range of 24,000 hours and a high-intensity light output. For these reasons, they are used for large area overhead lighting, such as in factories, warehouses, and sports arenas as well as for streetlights. Clear mercury lamps produce a greenish light due to mercury's combination of spectral lines. This is not flattering to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Light Sources
This is a list of sources of light, the visible part of the electromagnetic spectrum. Light sources produce photons from another energy source, such as heat, chemical reactions, or conversion of mass or a different frequency of electromagnetic energy, and include light bulbs and stars like the Sun. Reflectors (such as the moon, cat's eyes, and mirrors) do not actually produce the light that comes from them. Incandescence Incandescence is the emission of light from a hot body as a result of its temperature. * * Combustion Lamps * (obsolete) * * * (error) * * * * * *s * (obsolete) * * Other * - shock wave * * * * * * * * * * * * * Nuclear and high-energy particle * * ** ** * * * * * Celestial and atmospheric * Astronomical objects ** Sun (sunlight, solar radiation) *** *** **Star ( Starlight) *** Nova / supernova / hypernova *** **** *** ** *** *** *** *** *** * ** Meteor *** ** *** *Lightning ( Plasma) ** ** ** ** * Luminescence Luminesce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Patent And Trademark Office
The United States Patent and Trademark Office (USPTO) is an List of federal agencies in the United States, agency in the United States Department of Commerce, U.S. Department of Commerce that serves as the national patent office and trademark registration authority for the United States. The USPTO's headquarters are in Alexandria, Virginia, after a 2005 move from the Crystal City, Virginia, Crystal City area of neighboring Arlington County, Virginia, Arlington, Virginia. The USPTO is "unique among federal agencies because it operates solely on fees collected by its users, and not on taxpayer dollars". Its "operating structure is like a business in that it receives requests for services—applications for patents and trademark registrations—and charges fees projected to cover the cost of performing the services [it] provide[s]". The office is headed by the Under Secretary of Commerce for Intellectual Property, under secretary of commerce for intellectual property and directo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Typeface
A typeface (or font family) is a design of Letter (alphabet), letters, Numerical digit, numbers and other symbols, to be used in printing or for electronic display. Most typefaces include variations in size (e.g., 24 point), weight (e.g., light, bold), slope (e.g., italic), width (e.g., condensed), and so on. Each of these variations of the typeface is a font. There are list of typefaces, thousands of different typefaces in existence, with new ones being developed constantly. The art and craft of designing typefaces is called type design. Designers of typefaces are called type designers and are often employed by type foundry, type foundries. In desktop publishing, type designers are sometimes also called "font developers" or "font designers" (a typographer is someone who ''uses'' typefaces to design a page layout). Every typeface is a collection of glyphs, each of which represents an individual letter, number, punctuation mark, or other symbol. The same glyph may be used for ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wisconsin
Wisconsin ( ) is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. With a population of about 6 million and an area of about 65,500 square miles, Wisconsin is the List of U.S. states and territories by population, 20th-largest state by population and the List of U.S. states and territories by area, 23rd-largest by area. It has List of counties in Wisconsin, 72 counties. Its List of municipalities in Wisconsin by population, most populous city is Milwaukee; its List of capitals in the United States, capital and second-most populous city is Madison, Wisconsin, Madison. Other urban areas include Green Bay, Wisconsin, Green Bay, Kenosha, Wisconsin, Kenosha, Racine, Wisconsin, Racine, Eau Claire, Wisconsin, Eau Claire, and the Fox Cities. Geography of Wiscon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milwaukee
Milwaukee is the List of cities in Wisconsin, most populous city in the U.S. state of Wisconsin. Located on the western shore of Lake Michigan, it is the List of United States cities by population, 31st-most populous city in the United States and the fifth-most populous city in the Midwest with a population of 577,222 at the 2020 United States census, 2020 census. It is the county seat of Milwaukee County, Wisconsin, Milwaukee County. The Milwaukee metropolitan area is the Metropolitan statistical area, 40th-most populous metropolitan area in the U.S. with 1.57 million residents. Founded in the early 19th century and incorporated in 1846, Milwaukee grew rapidly due to its location as a port city. History of Milwaukee, Its history was heavily influenced by German immigrants and it continues to be a Germans in Milwaukee, center for German-American culture, specifically known for Beer in Milwaukee, its brewing industry. The city developed as an industrial powerhouse during the 19t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portmanteau
In linguistics, a blend—also known as a blend word, lexical blend, or portmanteau—is a word formed by combining the meanings, and parts of the sounds, of two or more words together.Garner's Modern American Usage p. 644. English examples include '' smog'', coined by blending ''smoke'' and ''fog'', and '''', from ''motor'' ('' motorist'') and ''hotel''. A blend is similar to a [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technical Term
Jargon, or technical language, is the specialized terminology associated with a particular field or area of activity. Jargon is normally employed in a particular communicative context and may not be well understood outside that context. The context is usually a particular occupation (that is, a certain trade, profession, vernacular or academic field), but any ingroup can have jargon. The key characteristic that distinguishes jargon from the rest of a language is its specialized vocabulary, which includes terms and definitions of words that are unique to the context, and terms used in a narrower and more exact sense than when used in colloquial language. This can lead outgroups to misunderstand communication attempts. Jargon is sometimes understood as a form of technical slang and then distinguished from the official terminology used in a particular field of activity. The terms ''jargon'', ''slang,'' and ''argot'' are not consistently differentiated in the literature; different a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Light
Thermal radiation is electromagnetic radiation emitted by the thermal motion of particles in matter. All matter with a temperature greater than absolute zero emits thermal radiation. The emission of energy arises from a combination of electronic, molecular, and lattice oscillations in a material. Kinetic energy is converted to electromagnetism due to charge-acceleration or dipole oscillation. At room temperature, most of the emission is in the infrared (IR) spectrum, though above around 525 °C (977 °F) enough of it becomes visible for the matter to visibly glow. This visible glow is called incandescence. Thermal radiation is one of the fundamental mechanisms of heat transfer, along with conduction and convection. The primary method by which the Sun transfers heat to the Earth is thermal radiation. This energy is partially absorbed and scattered in the atmosphere, the latter process being the reason why the sky is visibly blue. Much of the Sun's radiation transmits ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Spectroscopy
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functional groups in solid, liquid, or gaseous forms. It can be used to characterize new materials or identify and verify known and unknown samples. The method or technique of infrared spectroscopy is conducted with an instrument called an infrared spectrometer (or spectrophotometer) which produces an infrared spectrum. An IR spectrum can be visualized in a graph of infrared light absorbance (or transmittance) on the vertical axis vs. frequency, wavenumber or wavelength on the horizontal axis. Typical units of wavenumber used in IR spectra are reciprocal centimeters, with the symbol cm−1. Units of IR wavelength are commonly given in micrometers (formerly called "microns"), symbol μm, which are related to the wavenumber in a reciprocal way ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
