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The xenon short-arc lamps are made of a thin layer of fused quartz and contain xenon gas at a pressure of about 25 atmospheres ( 367 PSI ); because of this, projectionists are required to wear protective body armor when changing or handling these in case the lamp breaks ( e. g., due to a drop to the floor ) because of the danger from flying quartz shards when propelled by the high pressure of the Xenon gas within.
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xenon and short-arc
In order to achieve maximum efficiency, the xenon gas inside short-arc lamps is maintained at an extremely high pressure — up to 30 atmospheres ( 440 psi / 3040 kPa ) — which poses safety concerns.
To mitigate this, large xenon short-arc lamps are normally shipped in protective shields, which will contain the envelope fragments should breakage occur.
Because of the safety concerns, lamp manufacturers recommend the use of eye protection when handling xenon short-arc lamps.
Xenon short-arc lamps come in two distinct varieties: pure xenon, which contain only xenon gas ; and xenon-mercury, which contain xenon gas and a small amount of mercury metal.
As a result, the anode in a xenon short-arc lamp either has to be much larger than the cathode or be water-cooled, to dissipate the heat.
The output of a pure xenon short-arc lamp is relatively flat over the entire colour spectrum, though even in a high pressure lamp there are some very strong emission lines in the near infrared, roughly in the region from 850 – 900 nm.
Because of these characteristics, xenon short-arc lamps require a sophisticated power supply to achieve stable, long-life operation.
xenon and lamps
Historically, photolithography has used ultraviolet light from gas-discharge lamps using mercury, sometimes in combination with noble gases such as xenon.
Current designs use xenon flash lamps to produce an intense flash of white light, some of which is absorbed by the Nd: glass that produces the laser power.
The beam concentrates about 25, 000, 000 lumens from 39 7kW xenon lamps into its beam of about 40, 000, 000, 000 candela.
The type of lamp is often named by the gas contained in the bulb ; including neon, argon, xenon, krypton, sodium, metal halide, and mercury, or by the type of electrode as in carbon-arc lamps.
Even in these applications conventional carbon arc lamps are being pushed into obsolescence by xenon arc lamps.
Before " firing ", the amplifiers are first optically pumped by a total of 7, 680 xenon flash lamps ( the PAMs have their own smaller flash lamps as well ).
The Shuttle orbiters had no on-board lights, due to the difficulty of designing landing lights to survive re-entry, and so the runway was lit by high-intensity xenon arc lamps to guide the orbiter in.
At low current densities krypton flashlamps have higher output in those bands than do the more common xenon lamps, which produce more light at around 900 nm.
Various light sources may be used as excitation sources, including lasers, photodiodes, and lamps ; xenon arcs and mercury-vapor lamps in particular.
Intense pulsed light ( IPL ) epilators, though technically not containing a laser, use xenon flash lamps that emit full spectrum light.
Standard features include xenon HID headlamps with high pressure washers and auto levelers, front fog lamps, 17 " " Avus " alloy wheels with 225 / 45R17 tyres, electrically adjustable Recaro leather seats, climate control, alarm and Electronic Stability Programme ( ESP ) with traction control ( ASR ).
Modern lamps typically use combinations of xenon, krypton and neon, although other gases can be used as well.
A level of light comparable to sunlight was supplied in each of the 4 compartments by 20 kW xenon lamps, cooled by water jackets.
Three main types of light source are used ; xenon arc lamp or mercury-vapor lamps with an excitation filter, lasers and high-power LEDs.
Lasers are most widely used for more complex fluorescence microscopy techniques like confocal microscopy and total internal reflection fluorescence microscopy while xenon and mercury lamps with an excitation filter or LEDs are commonly used for widefield epifluorescence microscopes.
At one time, xenon bulbs offered the brightest light levels, but recent high-power LEDs are brighter and more efficient than comparable xenon-filled incandescent lamps.
Metal-halide lamps are used in automobile lighting, where are high-intensity discharge ( HID ) lamps are commonly known as " xenon headlamps " due to the use of xenon gas in the bulb instead of argon.
xenon and are
Three different wavelengths of ultraviolet radiation are selected by the variable filters placed in front of the three mercury xenon lights which serve as the ultraviolet sources.
Incandescent and xenon light sources require the vehicle ’ s engine to continue running to ensure that the battery is not depleted when the lights are used for a prolonged period.
The " inert " or noble chemical elements ( helium, neon, argon, krypton, xenon and radon ) are composed of lone atoms as their smallest discrete unit, but the other isolated chemical elements consist of either molecules or networks of atoms bonded to each other in some way.
Many of these buildings seem to have been planned in relation to each other: the baths at the northern end of the hippodrome are on the same alignment as it is, and the stoa, the xenon, the lower fountain, and the rows of seats all appear to have been built in an intentionally similar alignment.
The six noble gases that occur naturally are helium ( He ), neon ( Ne ), argon ( Ar ), krypton ( Kr ), xenon ( Xe ), and the radioactive radon ( Rn ).
Neon, argon, krypton, and xenon are obtained from air using the methods of liquefaction of gases and fractional distillation.
It was discovered ( along with krypton and xenon ) in the summer of 1898 as one of the three residual rare inert elements remaining in dry air, after nitrogen, oxygen, argon and carbon dioxide are removed.
The noble gases argon, krypton, and xenon are more narcotic than nitrogen at a given pressure, and xenon has so much anesthetic activity that it is actually a usable anesthetic at 80 % concentration and normal atmospheric pressure.
Xenon has historically been too expensive to be used very much in practice, but it has been successfully used for surgical operations, and xenon anesthesia systems are still being proposed and designed.
As the neutral xenon atoms diffuse into the channel of the thruster, they are ionized by collisions with high energy circulating electrons ( typically 10 – 40 eV, or about 10 % of the discharge voltage ).
Once ionized, the xenon ions typically have a charge of + 1, though a small fraction (~ 20 %) are + 2.
Because the majority of electrons are trapped in the Hall current, they have a long residence time inside the thruster and are able to ionize almost all of the xenon propellant, allowing for mass utilizations of 90 – 99 %.
Wannier-Mott excitons are typically found in semiconductor crystals with small energy gaps and high dielectric constants, but have also been identified in liquids, such as liquid xenon.
0.238 seconds.