Mr. Gowin made a cardboard cutout of his wife, Edith, to shield his eyes from the mercury vapor lamp and black light he used to attract the moths to a white sheet.
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After taking his Abitur, Leo Arons studied chemistry and physics, earning a doctorate degree in Strasbourg in 1888. As a scientist he worked in the area of experimental physics. He developed the mercury vapor lamp (also called "Arons' tube"), which was later marketed by AEG as "Dr. Arons' mercury vapor lamp". In 1890 he became a Privatdozent at the Friedrich-Wilhelms-Universität Berlin (now Humboldt University of Berlin).
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A 175-watt mercury-vapor light approximately 15 seconds after starting W mercury vapor lamp. The small diagonal cylinder at the bottom of the arc tube is a resistor which supplies current to the starter electrode. 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 borosilicate glass bulb.
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88 In February 1896 Herbert John Dowsing and H. S. Keating of England patented a mercury vapor lamp, considered by some to be the first true mercury vapor lamp.Mercury vapour lamps and action of ultra violet rays – Transactions of the Faraday Society (RSC Publishing) The first mercury vapor lamp to achieve widespread success was invented in 1901 by American engineer Peter Cooper Hewitt. Hewitt was issued on September 17, 1901. In 1903, Hewitt created an improved version that possessed higher color qualities which eventually found widespread industrial use.
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The spectral lines of mercury vapor lamp at wavelength 546.1 nm, showing anomalous Zeeman effect. (A) Without magnetic field. (B) With magnetic field, spectral lines split as transverse Zeeman effect. (C) With magnetic field, split as longitudinal Zeeman effect.
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Warm-up of a color corrected 80 W high-pressure mercury vapor lamp to half brightness When a mercury vapor lamp is first turned on, it will produce a dark blue glow because only a small amount of the mercury is ionized and the gas pressure in the arc tube is very low, so much of the light is produced in the ultraviolet mercury bands. As the main arc strikes and the gas heats up and increases in pressure, the light shifts into the visible range and the high gas pressure causes the mercury emission bands to broaden somewhat, producing a light that appears more nearly white to the human eye, although it is still not a continuous spectrum. Even at full intensity, the light from a mercury vapor lamp with no phosphors is distinctly bluish in color. The pressure in the quartz arc-tube rises to approximately one atmosphere once the bulb has reached its working temperature.
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A low-pressure mercury-vapor lamp at 254 nm in a photochemical reactor is used for 5–8 hours until all the diazoketone has been consumed as determined by TLC analysis. Dichloromethane, chloroform, and 1,2-dichloroethane, are all appropriate solvents for the annulation reaction.
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Cooper Hewitt's mercury vapor lamp, the forerunner of the fluorescent lamp. In 1901 he invented and patented a mercury-vapor lamp; a gas-discharge lamp that used mercury vapor produced by passing current through liquid mercury. His first lamps had to be started by tilting the tube to make contact between the two electrodes and the liquid mercury; later he developed the inductive electrical ballast to start the tube. The efficiency was much higher than that of incandescent lamps, but the emitted light was of a bluish-green unpleasant color, which limited its practical use to specific professional areas, like photography, where the color was not an issue at a time where films were black and white.
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Otto Richard Lummer (July 17, 1860 – July 5, 1925) was a German physicist and researcher. He was born in the city of Gera, Germany. With Leon Arons, Lummer helped to design and build the Arons–Lummer mercury-vapor lamp. Lummer primarily worked in the field of optics and thermal radiation.
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Peter Cooper Hewitt (May 5, 1861 – August 25, 1921) was an American electrical engineer and inventor, who invented the first mercury-vapor lamp in 1901. Hewitt was issued on September 17, 1901. In 1903, Hewitt created an improved version that possessed higher color qualities which eventually found widespread industrial use.
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The torch is a functioning mercury-vapor lamp, casting a blue-green light at night. The torch in her right hand was supposed to be a working light continuously, but it remained dark until it was reconstructed in 1959. Tube and trolley systems have been installed so the bulb can be changed from the inside.
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The increase in pressure results in further brightening of the lamp. The entire warm-up process takes roughly 4 to 7 minutes. Some bulbs include a thermal switch which shorts the starting electrode to the adjacent main electrode, extinguishing the starting arc once the main arc strikes. The mercury vapor lamp is a negative resistance device.
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This means its resistance decreases as the current through the tube increases. So if the lamp is connected directly to a constant-voltage source like the power lines, the current through it will increase until it destroys itself. Therefore, it requires a ballast to limit the current through it. Mercury vapor lamp ballasts are similar to the ballasts used with fluorescent lamps.
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Photochemical immersion well reactor (750 mL) with a mercury-vapor lamp Photochemical reactions require a light source that emits wavelengths corresponding to an electronic transition in the reactant. In the early experiments (and in everyday life), sunlight was the light source, although it is polychromatic. Mercury-vapor lamps are more common in the laboratory. Low pressure mercury vapor lamps mainly emit at 254 nm.
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Bioglass 8625 has a significant content of iron, which provides infrared light absorption and allows sealing by a light source, e.g. a Nd:YAG laser or a mercury-vapor lamp. The content of Fe2O3 yields high absorption with maximum at 1100 nm, and gives the glass a green tint. The use of infrared radiation instead of flame or contact heating helps preventing contamination of the device.
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A mercury vapor lamp is a line lamp, meaning it emits light near peak wavelengths. By contrast, a xenon arc has a continuous emission spectrum with nearly constant intensity in the range from 300-800 nm and a sufficient irradiance for measurements down to just above 200 nm. Filters and/or monochromators may be used in fluorimeters. A monochromator transmits light of an adjustable wavelength with an adjustable tolerance.
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After printing, the ink is cured by exposure to strong UV-light. Ink is exposed to UV radiation where a chemical reaction takes place where the photo-initiators cause the ink components to cross-link into a solid. Typically a shuttered mercury-vapor lamp or UV LED is used for the curing process. Curing processes with high power for short periods of times (microseconds) allow curing inks on thermally sensitive substrates.
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Subsequent products of photochlorination of methane (schematic representation without consideration of stoichiometry). An example of photochlorination at low temperatures and under ambient pressure is the chlorination of chloromethane to dichloromethane. The liquefied chloromethane (boiling point -24 °C) is mixed with chlorine in the dark and then irradiated with a mercury-vapor lamp. The resulting dichloromethane has a boiling point of 41 °C and is later separated by distillation from methyl chloride.
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A 9 W germicidal lamp in a compact fluorescent lamp form factor Germicidal UV for disinfection is most typically generated by a mercury-vapor lamp. Low-pressure mercury vapor has a strong emission line at 254 nm, which is within the range of wavelengths that demonstrate strong disinfection effect. The optimal wavelengths for disinfection are close to 260 nm. Mercury vapor lamps may be categorized as either low-pressure (including amalgam) or medium-pressure lamps.
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Unlike Moore's lamps, Hewitt's were manufactured in standardized sizes and operated at low voltages. The mercury-vapor lamp was superior to the incandescent lamps of the time in terms of energy efficiency, but the blue- green light it produced limited its applications. It was, however, used for photography and some industrial processes. Mercury vapor lamps continued to be developed at a slow pace, especially in Europe, and by the early 1930s they received limited use for large-scale illumination.
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In the EU the use of low efficiency mercury vapor lamps for lighting purposes was banned in 2015. It does not affect the use of mercury in compact fluorescent lamp, nor the use of mercury lamps for purposes other than lighting.Phasing out of mercury vapor lamps. www.osram.co.uk. Retrieved on 2015-03-18. In the US, ballasts for mercury vapor lamps for general illumination, excluding specialty application mercury vapor lamp ballasts, were banned after January 1, 2008.
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Photochemical immersion well reactor (50 mL) with a mercury-vapor lamp. Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm), visible light (400–750 nm) or infrared radiation (750–2500 nm). In nature, photochemistry is of immense importance as it is the basis of photosynthesis, vision, and the formation of vitamin D with sunlight.
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Several gas or metal-vapor lamps can also be used. When operated at low pressure and current, these lamps generally produce light in various spectral lines, with one or two lines being most predominant. Because these lines are very narrow, the lamps can be combined with narrow-bandwidth filters to isolate the strongest line. A helium-discharge lamp will produce a line at 587.6 nm (yellow), while a mercury-vapor lamp produces a line at 546.1 (yellowish green).
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Some of them employed fluorescent coatings, but these were used primarily for color correction and not for enhanced light output. Mercury vapor lamps also anticipated the fluorescent lamp in their incorporation of a ballast to maintain a constant current. Cooper-Hewitt had not been the first to use mercury vapor for illumination, as earlier efforts had been mounted by Way, Rapieff, Arons, and Bastian and Salisbury. Of particular importance was the mercury vapor lamp invented by Küch and Retschinsky in Germany.
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The ceramic metal halide is a variation of the metal-halide lamp which is itself a variation of the old (high-pressure) mercury-vapor lamp. A CMH uses ceramic instead of the quartz of a traditional metal halide lamp. Ceramic arc tubes allow higher arc tube temperatures, which some manufacturers claim results in better efficacy, color rendering, and color stability. The discharge is contained in a ceramic tube, usually made of sintered alumina, similar to that used in the high pressure sodium lamp.
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Some photographers prefer substituting the cyan emulsion in the CMYK separations with a cyanotype layer. A simple duotone separation combining orange watercolor pigment and a cyanotype can yield surprisingly beautiful results. Low density photographic negatives of the same size as the final image are used for exposing the print. No enlarger is used, but instead, a contact printing frame or vacuum exposure frame is used with an ultraviolet light source such as a mercury vapor lamp, a common fluorescent black light, or the sun.
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Self- ballasted (SB) lamps are mercury vapor lamps with a filament inside connected in series with the arc tube that functions as an electrical ballast. This is the only kind of mercury vapor lamp that can be connected directly to the mains without an external ballast. These lamps have only the same or slightly higher efficiency than incandescent lamps of similar size, but have a longer life. They give light immediately on startup, but usually need a few minutes to restrike if power has been interrupted.
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The extended lifespan and improved efficacy of incandescent bulbs negated one of the key advantages of Moore's lamp, but GE purchased the relevant patents in 1912. These patents and the inventive efforts that supported them were to be of considerable value when the firm took up fluorescent lighting more than two decades later. At about the same time that Moore was developing his lighting system, Peter Cooper Hewitt invented the mercury-vapor lamp, patented in 1901 (). Hewitt's lamp glowed when an electric current was passed through mercury vapor at a low pressure.
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In 1959, Robert Noyce built on Hoerni's work with his conception of an integrated circuit (IC), which added a layer of metal to the top of Hoerni's basic structure to connect different components, such as transistors, capacitors, or resistors, located on the same piece of silicon. The planar process provided a powerful way of implementing an integrated circuit that was superior to earlier conceptions of the integrated circuit. Noyce's invention was the first monolithic IC chip. Early versions of the planar process used a photolithography process using near-ultraviolet light from a mercury vapor lamp.
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Edmund Germer Edmund Germer (August 24, 1901 in Berlin - August 10, 1987) was a German inventor recognized as the father of the fluorescent lamp. He applied for a patent with Friedrich Meyer and Hans J. Spanner on December 10, 1926, which led to . The patent was later purchased by the General Electric Company, which also licensed his patent on the high-pressure mercury-vapor lamp. The idea of coating the tube of an arc lamp emitting in the ultraviolet with fluorescing powder to transform UV into visible light led to the realization of arc discharge emitters with spectral quality competing with incandescent emitters.
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The specimen is illuminated with light of a specific wavelength (or wavelengths) which is absorbed by the fluorophores, causing them to emit light of longer wavelengths (i.e., of a different color than the absorbed light). The illumination light is separated from the much weaker emitted fluorescence through the use of a spectral emission filter. Typical components of a fluorescence microscope are a light source (xenon arc lamp or mercury-vapor lamp are common; more advanced forms are high-power LEDs and lasers), the excitation filter, the dichroic mirror (or dichroic beamsplitter), and the emission filter (see figure below).
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An EPROM (rarely EROM), or erasable programmable read-only memory, is a type of programmable read-only memory (PROM) chip that retains its data when its power supply is switched off. Computer memory that can retrieve stored data after a power supply has been turned off and back on is called non-volatile. It is an array of floating-gate transistors individually programmed by an electronic device that supplies higher voltages than those normally used in digital circuits. Once programmed, an EPROM can be erased by exposing it to strong ultraviolet light source (such as from a mercury-vapor lamp).
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At Halle he established a clinic for skin and venereal diseases that eventually acquired the status of a university clinic. In 1901 he received the title of professor at the university, then in 1904 relocated to Berlin, where he opened a private practice.Ernst Kromayer Catalogus Professorum HalensisErnst Kromayer (1862–1933) Bürgerstiftung Halle (Saale) He is best remembered for inventing a water-cooled mercury-vapor lamp (Kromayer lamp) for ultraviolet irradiation of the skin.Electrotherapy Explained: Principles and Practice by Valma J. Robertson, John Low, Alex Ward, Ann Reed On 23 October 1906 he received a patent for the lamp.
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Most go by the deluxe (DX) designation on the lamp and have a white appearance to the bulb. Mercury Vapor Bulbs come in either clear or coated with powers of 50, 75, 100, 175, 250, 400, 700 or 1,000 Watts. The Mercury Vapor lamp is considered obsolete by today's standards and many places are taking them out of service. As of 2008, the sale of new mercury vapor streetlights and ballasts was banned in the US by the Energy Policy Act of 2005, although the sale of new bulbs for existing fixtures does continue, but the bulbs were also banned in 2015 in Europe.
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One very common positive photoresist used with the I, G and H-lines from a mercury-vapor lamp is based on a mixture of diazonaphthoquinone (DNQ) and novolac resin (a phenol formaldehyde resin). DNQ inhibits the dissolution of the novolac resin, but upon exposure to light, the dissolution rate increases even beyond that of pure novolac. The mechanism by which unexposed DNQ inhibits novolac dissolution is not well understood, but is believed to be related to hydrogen bonding (or more exactly diazocoupling in the unexposed region). DNQ-novolac resists are developed by dissolution in a basic solution (usually 0.26N tetramethylammonium hydroxide (TMAH) in water).
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Perkin-Elmer responded with the Microprojector, which was, in effect, a large photocopier system. The mask was placed in a holder and never touched the surface of the chip, instead, the image was projected onto the surface. Making this work required a complex 16-element lens system that only focussed a single frequency of light onto the mask, and the rest of the light from the 1,000 W mercury-vapor lamp had to be filtered out. Harold Hemstreet was convinced it would be possible to simplify the concept, and Abe Offner began the development of a system using mirrors instead of lenses, which did not suffer from the multispectral focussing problems seen in lenses.
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In 1954, Robert Hanbury Brown and Richard Q. Twiss introduced the intensity interferometer concept to radio astronomy for measuring the tiny angular size of stars, suggesting that it might work with visible light as well. Soon after they successfully tested that suggestion: in 1956 they published an in-lab experimental mockup using blue light from a mercury-vapor lamp, and later in the same year, they applied this technique to measuring the size of Sirius. In the latter experiment, two photomultiplier tubes, separated by a few meters, were aimed at the star using crude telescopes, and a correlation was observed between the two fluctuating intensities. Just as in the radio studies, the correlation dropped away as they increased the separation (though over meters, instead of kilometers), and they used this information to determine the apparent angular size of Sirius.
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For that major change in approach, the light used had to be both monochromatic and coherent, properties that were already a requirement on the radar radiation. Lasers also then being in the future, the best then-available approximation to a coherent light source was the output of a mercury vapor lamp, passed through a color filter that was matched to the lamp spectrum's green band, and then concentrated as well as possible onto a very small beam- limiting aperture. While the resulting amount of light was so weak that very long exposure times had to be used, a workable optical correlator was assembled in time to be used when appropriate data became available. Although creating that radar was a more straightforward task based on already-known techniques, that work did demand the achievement of signal linearity and frequency stability that were at the extreme state of the art.
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