The radiation ionizes, or knocks the electrons off of, the atoms in the gas.
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The WHIM is so hot that it ionizes hydrogen, stripping its single electron away.
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It steadily lets light out as it de-ionizes, resulting in the characteristic 143-day plateau in brightness.
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Apparently, when heated by the bulb, the salt supposedly ionizes the air for a better sleep at night.
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But an ion thruster ionizes the propellants, creating charged particles that can be accelerated further using an electric field.
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The molecular ion is formed when the radiation of the star, reaching temperatures more than 100,000 degrees, ionizes the nebula.
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For the unfamiliar, aura reading and photography uses a special type of camera that ionizes the air around the person posing for a photo.
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As this expelled gas travels through the interstellar material, it heats up and ionizes it, producing the faint glow that Hubble's Wide Field Camera 3 has captured here.
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If oxygen was present, their models of the galaxy suggested that it would be undergoing the process of cosmic re-ionization, where space radiation ionizes clouds of gas.
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Their process actually ionizes the air around the object in the photo (living or nonliving), and any water in the air will be visible as layers of glowing colors.
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This ionizes the medium and creates an "electrical arc" between the electrodes, characterized by a high current, high temperature, and the visible flash—the result of ionization in the medium.
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It features a heat-resistant dimmer to adjust the light as you like it, and when it's heated by the light, the lamp supposedly ionizes the air for a better sleep at night.
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As this radiation (often, but not necessarily in the form of a high-energy photon) bores through the icy film, it ionizes the matter it comes in contact with, knocking off a large number of low-energy electrons in the process.
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As the gas re-ionizes, it also releases a tremendous flare of light, like you see happening in this simulation of the process over a 5 million year timelapse:Video: S. Chon / University of TokyoBecause the flare is so bright, researchers hoped that, even at a distance of 13.1 billion light years, they would still be able to detect it with ALMA.
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Water ionizes into hydronium (H3O) cations and hydroxyl (OH) anions. The concentration of ionized hydrogen (as protonated water) is expressed as pH.
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It is also associated with a nearby star cluster that contains several massive stars. Sharpless 2-88B2 is a HII region ionized by a star that is dimmer than B0.5 V, and is ultracompact. HD 338916 is an emission line star that ionizes a close nebula in the Vulpecula OB1 association. It has an apparent magnitude (V) of 10.17 and a spectral type of O8 D. HD 338926 is another emission line star that ionizes a close nebula in the Vulpecula OB1 association.
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The capacitor is then discharged. The gap between the electrodes ionizes, turning the non-flammable propellant medium into a superheated conductive plasma. Associated volumetric expansion propels the projectile from the barrel at high velocity.
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U.S. Army White Sands Missile Range, Nuclear Environment Survivability. Report ADA278230. p. D-7. 15 April 1994. E1 is produced when gamma radiation from the nuclear detonation ionizes (strips electrons from) atoms in the upper atmosphere.
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An electrolaser first ionizes its target path, and then sends an electric current down the conducting track of ionized plasma, somewhat like lightning. It functions as a giant, high-energy, long-distance version of the Taser or stun gun.
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Conceptual diagram of an electrostatic precipitator The most basic precipitator contains a row of thin vertical wires, and followed by a stack of large flat metal plates oriented vertically, with the plates typically spaced about 1 cm to 18 cm apart, depending on the application. The air stream flows horizontally through the spaces between the wires, and then passes through the stack of plates. A negative voltage of several thousand volts is applied between wire and plate. If the applied voltage is high enough, an electric corona discharge ionizes the air around the electrodes, which then ionizes the particles in the air stream.
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APPI can ionize both polar and nonpolar species, and an APPI spectrum can be generated in just a few seconds. However, APPI ionizes a broad range of compound classes and produces both protonated and molecular ion peaks, resulting in a complex mass spectrum.
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This radiation rapidly ionizes the surrounding interstellar gas of the giant molecular cloud, forming an H II region or Strömgren sphere. In lists of spectra the "spectrum of OB" refers to "unknown, but belonging to an OB association so thus of early type".
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Helical xenon flashtube being fired Frame 1: The tube is dark. Frame 2: The trigger pulse ionizes the gas. Spark streamers form. Frame 3: Spark streamers connect and move away from the glass, and a plasma tunnel forms allowing amperes to surge.
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Within the discharge plasma, the sample evaporates, atomizes, and ionizes via electron impact. The total ion current may be optimized by adjusting the distance between the electrodes. This mode of ionization can be used to ionize conducting, semi-conducting, and non-conducting samples.
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Hydrogen cyanide is a linear molecule, with a triple bond between carbon and nitrogen. A minor tautomer of HCN is HNC, hydrogen isocyanide. Hydrogen cyanide is weakly acidic with a pKa of 9.2. It partially ionizes in water solution to give the cyanide anion, CN−.
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This is a basic explanation of how a pinch works. (1) Pinches apply a huge voltage across a tube. This tube is filled with fusion fuel, typically deuterium gas. If the product of the voltage & the charge is higher than the ionization energy of the gas the gas ionizes.
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The fuel ionizes and is accelerated towards the inner cage. If the ions miss the inner cage, they can fuse together. Fusors are not considered part of the CBFR family, because they do not traditionally use beams. There are numerous problems with the fusor as a fusion power reactor.
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All three components are massive stars, and the intense ultraviolet radiation they give off ionizes the gas of IC 1396, and causes compression denser globules of the nebula, leading to star formation. The stellar wind produced by the stars is strong enough to strip nearby stars of their protoplanetary disks.
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Phosphorous acid, is the compound described by the formula H3PO3. This acid is diprotic (readily ionizes two protons), not triprotic as might be suggested by this formula. Phosphorous acid is an intermediate in the preparation of other phosphorus compounds. Organic derivatives of phosphorous acid, compounds with the formula RPO3H2, are called phosphonic acids.
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A common kind of hydrolysis occurs when a salt of a weak acid or weak base (or both) is dissolved in water. Water spontaneously ionizes into hydroxide anions and hydronium cations. The salt also dissociates into its constituent anions and cations. For example, sodium acetate dissociates in water into sodium and acetate ions.
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At higher energies ionization tends to occur more than chemical dissociations. In a typical reactive gas, 1 in 100 molecules form free radicals whereas only 1 in 106 ionizes. The predominant effect here is the forming of free radicals. Ionic effects can predominate with selection of process parameters and if necessary the use of noble gases.
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Water ionizes into hydronium (H3O+) cations and hydroxide (OH−) anions. The concentration of ionized hydrogen (as protonated water) is expressed as pH. Low pH values increase rate of corrosion while high pH values encourage scale formation. Amphoterism is uncommon among metals used in water cooling systems, but aluminum corrosion rates increase with pH values above 9.
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Bacteria exposed to phloxine B die from oxidative damage. Phloxine B ionizes in water to become a negatively charged ion that binds to positively charged cellular components . When phloxine B is subjected to light, debromination occurs and free radicals and singlet oxygen are formed. These compounds cause irreversible damage to the bacteria, leading to growth arrest and cell death.
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A high voltage spark briefly ionizes the air within the torch head. This makes the air conductive and allows the "pilot arc" to form. The pilot arc forms within the torch head, with current flowing from the electrode to the nozzle inside the torch head. The pilot arc burns up the nozzle, a consumable part, while in this phase.
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HID connected to a GC has the great advantage to use helium as both the carrier gas and the ionization gas. HID is an ion detector which uses a radioactive source, typically β-emitters, to create metastable helium species. The radioactive source ionizes helium atoms by bombarding them with emissions. The metastable helium species have an energy of up to 19.8 eV.
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Krypton arc plasma. The dark space near the anode is filled with free electrons that have been stripped from neutral atoms, ionizing the atoms. The ions then speed away from the anode, colliding with neutral atoms to produce the light. As the current pulse travels through the tube, it ionizes the atoms, causing them to jump to higher energy-levels.
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Soft laser desorption is a soft ionization technique which desorbs and ionizes molecules from surfaces with minimal fragmentation. This is useful for a broad range of small and large molecules and molecules that fragment easily. The first soft laser desorption techniques included Matrix- assisted laser desorption/ionization (MALDI) nanoparticles in glycerol. In MALDI, the analyte is first mixed with a matrix solution.
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The radioactive source emits alpha particles into both chambers, which ionizes some air molecules. There is a potential difference (voltage) between pairs of electrodes in the chambers; the electrical charge on the ions allows an electric current to flow. The currents in both chambers should be the same as they are equally affected by air pressure, temperature, and the ageing of the source.
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Urea contains a carbonyl group. The more electronegative oxygen atom pulls electrons away from the carbon forming a greater electron density around the oxygen, giving the oxygen a partial negative charge and forming a polar bond. When nitric acid is presented, it ionizes. A hydrogen cation contributed by the acid is attracted to the oxygen and forms a covalent bond [electrophile H+].
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The electrical arc ionizes some of the gas, thereby creating an electrically conductive channel of plasma. As electricity from the cutter torch travels down this plasma it delivers sufficient heat to melt through the work piece. At the same time, much of the high velocity plasma and compressed gas blow the hot molten metal away, thereby separating, i.e. cutting through, the work piece.
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CyTOF mass cytometer. Mass cytometry is a mass spectrometry technique based on inductively coupled plasma mass spectrometry and time of flight mass spectrometry used for the determination of the properties of cells (cytometry). In this approach, antibodies are conjugated with isotopically pure elements, and these antibodies are used to label cellular proteins. Cells are nebulized and sent through an argon plasma, which ionizes the metal- conjugated antibodies.
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A high-altitude electromagnetic pulse (HEMP) weapon is a NEMP warhead designed to be detonated far above the Earth's surface. The explosion releases a blast of gamma rays into the mid-stratosphere, which ionizes as a secondary effect and the resultant energetic free electrons interact with the Earth's magnetic field to produce a much stronger EMP than is normally produced in the denser air at lower altitudes.
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The lactate is excreted from the cell onto the tooth enamel then ionizes. The lactate ions demineralize the hydroxyapatite crystals causing the tooth to be degraded. The progression of pit and fissure caries resembles two triangles with their bases meeting along the junction of enamel and dentin. Teeth are bathed in saliva and have a coating of bacteria on them (biofilm) that continually forms.
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DMAPP ionizes to its respective allylic cation that undergoes electrophilic addition to the double bond of IPP. Upon loss of a proton, geranyl diphosphate (GPP) is formed. GPP undergoes an elimination reaction to form its corresponding allylic cation. Electrophilic addition of another IPP unit to the GPP cation results in a tertiary carbocation intermediate that forms a fifteen-carbon farnesyl diphosphate (FPP) upon loss of a proton.
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Also, the ionization energy of the last emitted photon must exceed that of the atom. The optical ionization schemes are denoted by the amount of photons necessary to make the ion pair. For the first two Schemes 1 and 2, two photons (and processes) are involved. One photon excites the atom from the ground state to an intermediate state while the second photon ionizes the atom.
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Most processes in a streamer discharge are two-body processes, where an electron collides with a neutral molecule. An important example is impact ionization, where an electron ionizes a neutral molecule. Therefore, the mean free path is inversely proportional to the gas number density. If the electric field is changed linearly with the gas number density, then electrons gain on average the same energy between collisions.
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SuWt 2 is a planetary nebula viewed almost edge-on in the constellation of Centaurus. It is believed that high UV radiations from an undiscovered white dwarf ionizes this nebula. Currently, there is a binary system consisting of two A-type main-sequence stars whose radiations are not enough to photo-ionize the surrounding nebula. The nebula is easily obscured by the brighter star, HD 121228.
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A strong electrolyte is a solution/solute that completely, or almost completely, ionizes or dissociates in a solution. These ions are good conductors of electric current in the solution. Originally, a "strong electrolyte" was defined as a chemical that, when in aqueous solution, is a good conductor of electricity. With a greater understanding of the properties of ions in solution, its definition was replaced by the present one.
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The pump excites the atom or molecule of interest, and the probe ionizes it. The electrons or positive ions resulting from this event are then detected. As the time delay between the pump and the probe are changed, the change in the energy (and sometimes emission direction) of the photo-products is observed. In some cases multiple photons of a lower energy are used as the ionizing probe.
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The conjugate base of sulfuric acid (H2SO4)—a dense, colourless, oily, corrosive liquid—is the hydrogen sulfate ion (), also called the bisulfate ion. Sulfuric acid is classified as a strong acid; in aqueous solutions it ionizes completely to form hydronium ions (H3O+) and hydrogen sulfate (). In other words, the sulfuric acid behaves as a Brønsted–Lowry acid and is deprotonated. Bisulfate has a molar mass of 97.078 g/mol.
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Trost spirotryprostatin B synthesis :Trost spirotryprostatin B synthesis In the synthesis developed by the Trost group, the stereochemistry at the spirocyclic ring juncture is established by a decarboxylation-prenylation sequence, reminiscent of the Carroll reaction. Here, a prenyl ester serves as both the nucleophile and electrophile precursor. Upon treatment with a chiral palladium catalyst the prenyl group ionizes and decarboxylates. The resulting ion pair subsequently recombines to generate the prenylated product.
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Properties of the molecules can be discovered by Coulomb explosion imaging. In this process, a laser ionizes all three atoms simultaneously, which then fly away from each other due to electrostatic repulsion and are detected. The helium trimer is large, being more than 100 Å, which is even larger than the helium dimer. The atoms are not arranged in an equilateral triangle, but instead form random shaped triangles.
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MEA carbon dioxide scrubbing is also used to regenerate the air on submarines. Solutions of MEA in water are used as a gas stream scrubbing liquid in amine treaters. For example, aqueous MEA is used to remove carbon dioxide (CO2) and hydrogen sulfide (H2S) from various gas streams; e.g., flue gas and sour natural gas.. The MEA ionizes dissolved acidic compounds, making them polar and considerably more soluble.
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Cryptochrome and Magnetic Sensing, University of Illinois at Urbana-Champaign Stimulated emission from the N-V− center has been demonstrated, though it could be achieved only from the phonon side-band (i.e. broadband light) and not from the ZPL. For this purpose, the center has to be excited at a wavelength longer than ~650 nm, as higher-energy excitation ionizes the center. The first continuous-wave room-temperature maser has been demonstrated.
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Rocky planets must orbit within the habitable zone for life to form. Although the habitable zone of such hot stars as Sirius or Vega is wide, hot stars also emit much more ultraviolet radiation that ionizes any planetary atmosphere. They may become red giants before advanced life evolves on their planets. These considerations rule out the massive and powerful stars of type F6 to O (see stellar classification) as homes to evolved metazoan life.
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When the grids are charged to a high voltage, the fuel gas ionizes. The field between the two then accelerates the fuel inward, and when it passes the inner grid the field drops and the ions continue inward towards the center. If they impact with another ion they may undergo fusion. If they do not, they travel out of the reaction area into the charged area again, where they are re-accelerated inward.
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Sample preparation for PI includes first ensuring the sample is in the gas phase. PI ionizes molecules by exciting the sample molecules with photons of light. This method only works if the sample and other components in the gas phase are excited by different wavelengths of light. It is important when preparing the sample, or photon source, that the wavelengths of ionization are adjusted to excite the sample analyte and nothing else.
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Acetic acid is a weak acid, so it only ionizes slightly. According to Le Chatelier's principle, the addition of acetate ions from sodium acetate will suppress the ionization of acetic acid and shift its equilibrium to the left. Thus the percent dissociation of the acetic acid will decrease, and the pH of the solution will increase. The ionization of an acid or a base is limited by the presence of its conjugate base or acid.
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Pitting occurs because the electrical voltage ionizes the pipe's interior copper metal, which reacts chemically with dissolved minerals in the water, creating copper salts; these copper salts are soluble in water and wash away. Microscopic pits eventually grow and consolidate to form pin holes. When one is discovered, there are almost certainly more that have not yet leaked. A complete discussion of stray current corrosion can be found in chapter 11, section 11.4.
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Time-resolved photoelectron spectroscopy and two-photon photoelectron spectroscopy (2PPE) combine a pump-probe scheme with angle-resolved photoemission. A first laser pulse is used to excite a material, a second laser pulse ionizes the system. The kinetic energy of the electrons from this process is then detected, through various methods including energy mapping, time of flight measurements etc. As above, the process is repeated many times, with different time delays between the probe pulse and the pump pulse.
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Radioactive decay of naturally occurring uranium (238U and 235U), thorium (232Th), and potassium (40K) in seafloor sediments collectively bombard the interstitial water with α, β, and γ radiation. The irradiation ionizes and breaks apart water molecules, eventually yielding H2. The products of this reaction are aqueous electrons (e−aq), hydrogen radicals (H·), protons (H+), and hydroxyl radicals (OH·). The radicals are highly reactive, therefore short-lived, and recombine to produce hydrogen peroxide (H2 O2), and molecular hydrogen (H2).
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Argon gas-discharge lamp forming the symbol for argon "Ar" Incandescent lights are filled with argon, to preserve the filaments at high temperature from oxidation. It is used for the specific way it ionizes and emits light, such as in plasma globes and calorimetry in experimental particle physics. Gas-discharge lamps filled with pure argon provide lilac/violet light; with argon and some mercury, blue light. Argon is also used for blue and green argon-ion lasers.
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Succinic acid is a white, odorless solid with a highly acidic taste. In an aqueous solution, succinic acid readily ionizes to form its conjugate base, succinate (). As a diprotic acid, succinic acid undergoes two successive deprotonation reactions: :(CH2)2(CO2H)2 → (CH2)2(CO2H)(CO2)− \+ H+ :(CH2)2(CO2H)(CO2)− → (CH2)2(CO2)22− \+ H+ The pKa of these processes are 4.3 and 5.6, respectively. Both anions are colorless and can be isolated as the salts, e.g.
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The thyratron is a special-purpose tube filled with low-pressure gas or mercury vapor. Like vacuum tubes, it contains a hot cathode and an anode, but also a control electrode which behaves somewhat like the grid of a triode. When the control electrode starts conduction, the gas ionizes, after which the control electrode can no longer stop the current; the tube "latches" into conduction. Removing anode (plate) voltage lets the gas de-ionize, restoring its non- conductive state.
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The Geiger counter, invented in 1908, is one of the earliest and most successful applications of sonification. A Geiger counter has a tube of low-pressure gas; each particle detected produces a pulse of current when it ionizes the gas, producing an audio click. The original version was only capable of detecting alpha particles. In 1928, Geiger and Walther Müller (a PhD student of Geiger) improved the counter so that it could detect more types of ionizing radiation.
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This creates a current that moves circularly in the direction of jθ. The current then creates a magnetic field in the outward radial direction (Br), which then creates a current in the gas that has just been released in the opposite direction of the original current. This opposite current ionizes the ammonia. The positively charged ions are accelerated away from the engine due to the electric field jθ crossing the magnetic field Br, due to the Lorentz Force.
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Piccadilly Circus, London, 1962 Neon lighting consists of brightly glowing, electrified glass tubes or bulbs that contain rarefied neon or other gases. Neon lights are a type of cold cathode gas-discharge light. A neon tube is a sealed glass tube with a metal electrode at each end, filled with one of a number of gases at low pressure. A high potential of several thousand volts applied to the electrodes ionizes the gas in the tube, causing it to emit colored light.
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They work on the principle that passing a high voltage through a low-pressure gas generates light. Essentially, a PDP can be viewed as a matrix of tiny fluorescent tubes which are controlled in a sophisticated fashion. Each pixel comprises a small capacitor with three electrodes, one for each primary color (some newer displays include an electrode for yellow). An electrical discharge across the electrodes causes the rare gases sealed in the cell to be converted to plasma form as it ionizes.
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The continued delivery of energy during the laser pulse rapidly heats and ionizes the vapor, converting it into a rapidly expanding plasma. The rising pressure exerted on the opaque overlay surface by the expanding plasma enters the target surface as a high amplitude stress wave or shock wave. Without a transparent overlay, the unconfined plasma plume moves away from the surface and the peak pressure is considerably lower. If the amplitude of the shock wave is above the Hugoniot Elastic Limit (HEL), i.e.
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An ion pump (also referred to as a sputter ion pump) is a type of vacuum pump which operates by sputtering a metal getter. Under ideal conditions, ion pumps are capable of reaching pressures as low as 10−11 mbar. An ion pump first ionizes gas within the vessel it is attached to and employs a strong electrical potential, typically 3–7 kV, which accelerates the ions into a solid electrode. Small bits of the electrode are sputtered into the chamber.
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The bond is 5000 times weaker than the covalent bond in the hydrogen molecule. Both helium atoms in the dimer can be ionized by a single photon with energy 63.86 eV. The proposed mechanism for this double ionization is that the photon ejects an electron from one atom, and then that electron hits the other helium atom and ionizes that as well. The dimer then explodes as two helium cations ions repel each other with the same speed but opposite directions.
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Columbia College. The two metal sheets are connected to a Tesla coil oscillator, which applies high-voltage radio frequency alternating current. An oscillating electric field between the sheets ionizes the low- pressure gas in the two long Geissler tubes in his hands, causing them to glow in a manner similar to neon tubes. After 1890, inventor Nikola Tesla experimented with transmitting power by inductive and capacitive coupling using spark-excited radio frequency resonant transformers, now called Tesla coils, which generated high AC voltages.
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Star-forming regions are a class of emission nebula associated with giant molecular clouds. These form as a molecular cloud collapses under its own weight, producing stars. Massive stars may form in the center, and their ultraviolet radiation ionizes the surrounding gas, making it visible at optical wavelengths. The region of ionized hydrogen surrounding the massive stars is known as an H II region while the shells of neutral hydrogen surrounding the H II region are known as photodissociation region.
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Corona discharge is a leakage of electric current into the air adjacent to high voltage conductors. It is sometimes visible as a dim blue glow in the air next to sharp points on high voltage equipment. The high electric field ionizes the air, making it conductive, allowing current to leak from the conductor into the air in the form of ions. In electric power transmission lines and equipment, corona results in an economically significant waste of power and may deteriorate the hardware from where it originates.
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Bow shocks form as a result of the interaction between the solar wind and the cometary ionosphere, which is created by ionization of gases in the coma. As the comet approaches the Sun, increasing outgassing rates cause the coma to expand, and the sunlight ionizes gases in the coma. When the solar wind passes through this ion coma, the bow shock appears. The first observations were made in the 1980s and 90s as several spacecraft flew by comets 21P/Giacobini–Zinner, 1P/Halley, and 26P/Grigg–Skjellerup.
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The Kratos MS 50, or EI 50, is a tool for electron ionization (EI). The EI 50, used for relatively small molecules (as opposed to methods like MALDI), ionizes molecules via electron ionization (normally under 70 electronvolt conditions) and then accelerates them through an electric potential. The spectroscopy is done by analyzing the different displacements by a magnet. For equal charge, these displacements depend only on velocity, thus for the EI 50's constant kinetic energy conditions, these displacements are uniquely determined by a particle's mass.
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The atomizer of an ICP The plasma used in an ICP-MS is made by partially ionizing argon gas (Ar → Ar+ \+ e−). The energy required for this reaction is obtained by pulsing an alternating electric current in load coil that surrounds the plasma torch with a flow of argon gas. After the sample is injected, the plasma's extreme temperature causes the sample to separate into individual atoms (atomization). Next, the plasma ionizes these atoms (M → M+ \+ e−) so that they can be detected by the mass spectrometer.
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As in the silicon detector, when a charged particle passes through the chamber it ionizes the gas. This signal is then carried to a nearby wire, which is then carried to the computers for read-out. The COT is approximately 3.1 m long and extends from r = 40 cm to r = 137 cm. Although the COT is not nearly as precise as the silicon detector, the COT has a hit position resolution of 140 μm and a momentum resolution of 0.0015 (GeV/c)−1.
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Free neutrons decay by emission of an electron and an electron antineutrino to become a proton, a process known as beta decay: In the adjacent diagram, a neutron collides with a proton of the target material, and then becomes a fast recoil proton that ionizes in turn. At the end of its path, the neutron is captured by a nucleus in an (n,γ)-reaction that leads to the emission of a neutron capture photon. Such photons always have enough energy to qualify as ionizing radiation.
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Aspirin has been shown to have at least three additional modes of action. It uncouples oxidative phosphorylation in cartilaginous (and hepatic) mitochondria, by diffusing from the inner membrane space as a proton carrier back into the mitochondrial matrix, where it ionizes once again to release protons. Aspirin buffers and transports the protons. When high doses are given, it may actually cause fever, owing to the heat released from the electron transport chain, as opposed to the antipyretic action of aspirin seen with lower doses.
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More energetic, shorter-wavelength "extreme" UV below 121 nm ionizes air so strongly that it is absorbed before it reaches the ground. However, ultraviolet light (specifically, UVB) is also responsible for the formation of vitamin D in most land vertebrates, including humans. The UV spectrum, thus, has effects both beneficial and harmful to life. The lower wavelength limit of human vision is conventionally taken as 400 nm, so ultraviolet rays are invisible to humans, although some people can perceive light at slightly shorter wavelengths than this.
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In this method a laser is tuned to a wavelength which excites only one isotope of the material and ionizes those atoms preferentially. The resonant absorption of light for an isotope is dependent upon its mass and certain hyperfine interactions between electrons and the nucleus, allowing finely tuned lasers to interact with only one isotope. After the atom is ionized it can be removed from the sample by applying an electric field. This method is often abbreviated as AVLIS (atomic vapor laser isotope separation).
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In 1916 Watson-Watt wanted a job with the War Office, but nothing obvious was available in communications. Instead he joined the Meteorological Office, which was interested in his ideas on the use of radio for the detection of thunderstorms. Lightning gives off a radio signal as it ionizes the air, and his goal was to detect this signal to warn pilots of approaching thunderstorms. The signal occurs across a wide range of frequencies, and could be easily detected and amplified by naval longwave sets.
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NSTAR ion thruster for the Deep Space 1 spacecraft during a hot fire test at the Jet Propulsion Laboratory NEXIS ion engine test (2005) An ion thruster or ion drive is a form of electric propulsion used for spacecraft propulsion. It creates thrust by accelerating ions using electricity. An ion thruster ionizes a neutral gas by extracting some electrons out of atoms, creating a cloud of positive ions. These ion thrusters rely mainly on electrostatics as ions are accelerated by the Coulomb force along an electric field.
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Antiproton annihilation occurs at the surface of the hemisphere, which ionizes the fuel. These ions heat the core of the pellet to fusion temperatures. The antiproton- driven Magnetically Insulated Inertial Confinement Fusion Propulsion (MICF) concept relies on self-generated magnetic field which insulates the plasma from the metallic shell that contains it during the burn. The lifetime of the plasma was estimated to be two orders of magnitude greater than implosion inertial fusion, which corresponds to a longer burn time, and hence, greater gain.
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The oscillating electric field ionizes the gas molecules by stripping them of electrons, creating a plasma. In each cycle of the field, the electrons are electrically accelerated up and down in the chamber, sometimes striking both the upper wall of the chamber and the wafer platter. At the same time, the much more massive ions move relatively little in response to the RF electric field. When electrons are absorbed into the chamber walls they are simply fed out to ground and do not alter the electronic state of the system.
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Atmospheric-pressure plasma treatment is very similar to corona treatment but there are a few differences between them. Both treatments may use one or more high voltage electrodes which charge the surrounding blown gas molecules and ionizes them. However, in atmospheric plasma systems, the overall plasma density is much greater which enhances the rate and degree to which the ionized molecules are incorporated onto a materials' surface. An increased rate of ion bombardment occurs which may result in stronger material bonding traits depending on the gas molecules used in the process.
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When such an arrangement is powered by high voltage (in the range of kilovolts per mm), the emitter ionizes molecules in the air that accelerate backwards to the collector, producing thrust in reaction. Along the way, these ions collide with electrically neutral air molecules and accelerate them in turn. The effect is not directly dependent on electrical polarity, as the ions may be positively or negatively charged. Reversing the polarity of the electrodes does not alter the direction of motion, as it also reverses the polarity of the ions to match.
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The most common metal halide compound used is sodium iodide. Once the arc tube reaches its running temperature, the sodium dissociates from the iodine, adding orange and reds to the lamp's spectrum from the sodium D line as the metal ionizes. As a result, metal-halide lamps have high luminous efficacy of around 75–100 lumens per watt, which is about twice that of mercury vapor lights and 3 to 5 times that of incandescent lights and produce an intense white light. Lamp life is 6,000 to 15,000 hours.
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During normal operation, the voltage between the main electrodes is somewhat lower than the breakdown voltage corresponding to their distance and the dielectric between them (usually air, argon-oxygen, nitrogen, hydrogen, or sulfur hexafluoride). To switch the device, a high-voltage pulse is delivered to the triggering electrode. This ionizes the medium between it and one of the main electrodes, creating a spark which shortens the thickness of non-ionized medium between the electrodes. The triggering spark also generates ultraviolet light and free electrons in the main gap.
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A portable XRF analyzer using a silicon drift detector In energy-dispersive analysis, dispersion and detection are a single operation, as already mentioned above. Proportional counters or various types of solid-state detectors (PIN diode, Si(Li), Ge(Li), Silicon Drift Detector SDD) are used. They all share the same detection principle: An incoming X-ray photon ionizes a large number of detector atoms with the amount of charge produced being proportional to the energy of the incoming photon. The charge is then collected and the process repeats itself for the next photon.
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The radioactive foil emits a beta particle (electron) which collides with and ionizes the carrier gas to generate more ions resulting in a current. When analyte molecules with electronegative / withdrawing elements or functional groups electrons are captured which results in a decrease in current generating a detector response. Nitrogen–phosphorus detector (NPD), a form of thermionic detector where nitrogen and phosphorus alter the work function on a specially coated bead and a resulting current is measured. Dry electrolytic conductivity detector (DELCD) uses an air phase and high temperature (v.
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The duoplasmatron has two different types of plasma: the cathode plasma which is close to the cathode and the anode plasma that is close to the anode. The cathode works by injecting a beam of electrons with a suitable amount of energy. This injection ionizes the gas molecules, typically Argon gas, in the anode and increases the potential near the anode. The ions that are repulsed, however, combine with the ions that contain enough energy to pass the deceleration region and this combination of ions fill the expansion cup with directed ions and electrons.
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A Fast Low-Ionization Emission Region, or FLIER, is a volume of gas with low ionization, moving at supersonic speeds, near the symmetry axis of many planetary nebulae. Their outflow speeds are significantly higher than the nebulae in which they are embedded, and their ionizations are much lower. FLIERs' high speeds suggest ages much younger than their parent nebulae, and their low ionizations indicate that the ultraviolet radiation that ionizes the gas around them does not penetrate into the FLIERs. The Blinking Planetary features a set of FLIERs.
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Ultraviolet, of wavelengths from 10 nm to 125 nm, ionizes air molecules, causing it to be strongly absorbed by air and by ozone (O3) in particular. Ionizing UV therefore does not penetrate Earth's atmosphere to a significant degree, and is sometimes referred to as vacuum ultraviolet. Although present in space, this part of the UV spectrum is not of biological importance, because it does not reach living organisms on Earth. There is a zone of the atmosphere in which ozone absorbs some 98% of non-ionizing but dangerous UV-C and UV-B.
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For electrons the energy loss is slightly different due to their small mass (requiring relativistic corrections) and their indistinguishability, and since they suffer much larger losses by Bremsstrahlung, terms must be added to account for this. Fast charged particles moving through matter interact with the electrons of atoms in the material. The interaction excites or ionizes the atoms, leading to an energy loss of the traveling particle. The non-relativistic version was found by Hans Bethe in 1930; the relativistic version (shown below) was found by him in 1932.
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"Ceravision and Toshiba Electronics Sign Development and Supply Agreement to Advance High Efficiency Plasma Technology", PR Newswire The lamp consists of four integrated elements; a quartz RF resonator and integral plasma burner (lamp), a transition unit (the system which couples the RF source to the resonator), a magnetron, and an AC power supply. The resonator and integrated burner contain an inert gas and metal halide salts. Microwave energy ionizes the gas to form the plasma which combines with the metal halide to vaporize the metal halide salts and produce the light.
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Some LINER nuclei may be powered by hot, young stars found in star formation regions, whereas other LINER nuclei may be powered by active galactic nuclei (highly energetic regions that contain supermassive black holes). Infrared spectroscopy observations have demonstrated that the nucleus of the Sombrero Galaxy is probably devoid of any significant star formation activity. However, a supermassive black hole has been identified in the nucleus (as discussed in the subsection below), so this active galactic nucleus is probably the energy source that weakly ionizes the gas in the Sombrero Galaxy.
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The magnet is positioned so that the area where the field loops over from the center to outside, where the field lines are roughly horizontal, is aligned with the bottom of the inner cylinder. A small amount of gas is introduced to the area between the cylinders. A large electric charge supplied by a capacitor bank applied across the cylinders ionizes the gas. Currents induced in the resulting plasma interact with the original magnetic field, generating a Lorentz force that pushes the plasma away from the inner cylinder, into the empty area.
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The removal of an electron from the purified sample is consequently achieved by heating the filament enough to release an electron, which then ionizes the atoms of the sample. TIMS utilizes a magnetic sector mass analyzer to separate the ions based on their mass to charge ratio. The ions gain velocity by an electrical potential gradient and are focused into a beam by electrostatic lenses. The ion beam then passes through the magnetic field of the electromagnet where it is partitioned into separate ion beams based on the ion's mass/charge ratio.
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Aspirin has been shown to have three additional modes of action. It uncouples oxidative phosphorylation in cartilaginous (and hepatic) mitochondria, by diffusing from the intermembrane space as a proton carrier back into the mitochondrial matrix, where it ionizes once again to release protons. In short, aspirin buffers and transports the protons, acting as a competitor to ATP synthase. When high doses of aspirin are given, aspirin may actually cause hyperthermia due to the heat released from the electron transport chain, as opposed to the antipyretic action of aspirin seen with lower doses.
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A close examination shows that the peak in the angular distribution is not actually exactly at the north or south pole, but rather at an angle of about 45 degrees. This has to do with the polarization of the laser that ionizes the O(1D), and can be analyzed to show that the angular momentum of this atom (which has 2 units) is aligned relative to the velocity of recoil. More detail can be found elsewhere. There are other dissociation channels available to ozone following excitation at this wavelength.
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Pinch-based devices are the earliest systems to be seriously developed for fusion research, starting with very small machines built in London in 1948. These normally took one of two forms; linear pinch machines are straight tubes with electrodes at both ends to apply the current into the plasma, whereas toroidal pinch machines are donut-shaped machines with large magnets wrapped around them that supply the current via magnetic induction. In both types of machines, a large burst of current is applied to a dilute gas inside the tube. This current initially ionizes the gas into a plasma.
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It does so in a time-dependent rather than dose-dependent manner, meaning that risk can be minimized by reducing the duration of use. Amikacin causes nephrotoxicity (damage to the kidneys), by acting on the proximal renal tubules. It easily ionizes to a cation and binds to the anionic sites of the epithelial cells of the proximal tubule as part of receptor-mediated pinocytosis. The concentration of amikacin in the renal cortex becomes ten times that of amikacin in the plasma; it then most likely interferes with the metabolism of phospholipids in the lysosomes, which causes lytic enzymes to leak into the cytoplasm.
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Materials scientists have not yet arrived at a full understanding of the effect, but the current theory of triboluminescence -- based upon crystallographic, spectroscopic, and other experimental evidence -- is that upon fracture of asymmetrical materials, charge is separated. When the charges recombine, the electrical discharge ionizes the surrounding air, causing a flash of light. Research further suggests that crystals which display triboluminescence must lack symmetry (thus being anisotropic in order to permit charge separation) and be poor conductors. However, there are substances which break this rule, and which do not possess asymmetry, yet display triboluminescence anyway, such as hexakis(antipyrine)terbium iodide.
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The generation of discrete Townsend avalanches in a proportional counter. Plot of electric field strength at the anode, showing the boundary of avalanche region. In a proportional counter the fill gas of the chamber is an inert gas which is ionized by incident radiation, and a quench gas to ensure each pulse discharge terminates; a common mixture is 90% argon, 10% methane, known as P-10. An ionizing particle entering the gas collides with an atom of the inert gas and ionizes it to produce an electron and a positively charged ion, commonly known as an "ion pair".
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The electric field ionizes some of the mercury atoms to produce free electrons, and then accelerates those free electrons. When the free electrons collide with mercury atoms, some of those atoms absorb energy from the electrons and are “excited” to higher energy levels. After a short delay, the excited mercury atoms spontaneously relax to their original lower energy state and emit a UV photon with the excess energy. As in a conventional fluorescent tube, the UV photon diffuses through the gas to the inside of the outer bulb, and is absorbed by the phosphor coating that surface, transferring its energy to the phosphor.
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Demonstration of the restored 1907 Massie Wireless Station spark gap transmitter #The cycle begins when current from the transformer charges up the capacitor, storing electric charge on its plates. While the capacitor is charging the spark gap is in its nonconductive state, preventing the charge from escaping through the coil. #When the voltage on the capacitor reaches the breakdown voltage of the spark gap, the air in the gap ionizes, starting an electric spark, reducing its resistance to a very low level (usually less than one ohm). This closes the circuit between the capacitor and the coil.
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Some emergency lighting is based on strobe lights similar to those used in flash photography. These xenon flash lamps put out a very brief but very bright flash by discharging a large current through a gas which ionizes the gas. The light produced has a somewhat bluish emission spectrum, which makes red lightbars glow a fuchsia-pink color when lit. Strobe lighting did provide intense light which could improve visibility, but the short duration of the individual flash made it necessary to design the electronics to issue multiple consecutive flashes before alternating with the other associated lens pair.
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The electron is initially treated quantum mechanically as it tunnel ionizes from the parent atom, but then its subsequent dynamics are treated classically. The electron is assumed to be born into the vacuum with zero initial velocity, and to be subsequently accelerated by the laser beam's electric field. The three-step model Half an optical cycle after ionization, the electron will reverse direction as the electric field changes, and will accelerate back towards the parent nucleus. Upon returning to the parent nucleus it can then emit bremsstrahlung-like radiation during a recombination process with the atom as it returns to its ground state.
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The gas in the bulb ionizes, starting a glow discharge, and its resistance drops to a low value. In its conducting state the current through the bulb is limited only by the external circuit. The voltage across the bulb drops to a lower voltage called the maintaining voltage Vm. The bulb will continue to conduct current until the applied voltage drops below the extinction voltage Ve (point d), which is usually close to the maintaining voltage. Below this voltage, the current provides insufficient energy to keep the gas ionized, so the bulb switches back to its high resistance, nonconductive state (point a).
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The birth of an O-type star in a molecular cloud has a destructive effect on the cloud, but also may trigger the formation of new stars. O-type stars emit copious amounts of ultraviolet radiation, which ionizes the gas in the cloud and pushes it away. O-type stars also have powerful stellar winds, with velocities of thousands of kilometers per second, which can blow a bubble in the molecular cloud around the star. O-type stars explode as supernovae when they die, releasing vast amounts of energy, contributing to the disruption of a molecular cloud.
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HID headlamp bulbs do not run on low-voltage DC current, so they require a ballast with either an internal or external ignitor. The ignitor is integrated into the bulb in D1 and D3 systems, and is either a separate unit or part of the ballast in D2 and D4 systems. The ballast controls the current to the bulb. The ignition and ballast operation proceeds in three stages: # Ignition: a high voltage pulse is used to produce an electrical arc – in a manner similar to a spark plug – which ionizes the xenon gas, creating a conducting channel between the tungsten electrodes.
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In the Hammer universe, a powergun is a weapon which projects high energy copper plasma toward its target. This plasma is created by inducing an electrical field in a precisely aligned group of copper atoms; the atoms' alignment causes a resonance which greatly amplifies the field energy and ionizes the atoms. The resulting plasma is directed by a firing chamber and barrel made of refractory metal, such as iridium; the chamber and barrel are cooled between shots by injected gas (typically nitrogen). The copper atoms are stored as individual charges, with the atoms held in the correct alignment by a plastic matrix which is mostly consumed by the firing.
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Upon contact, H2O and HCl combine to form hydronium cations H3O+ and chloride anions Cl− through a reversible chemical reaction: :HCl + H2O → H3O+ \+ Cl− The resulting solution is called hydrochloric acid and is a strong acid. The acid dissociation or ionization constant, Ka, is large, which means HCl dissociates or ionizes practically completely in water. Even in the absence of water, hydrogen chloride can still act as an acid. For example, hydrogen chloride can dissolve in certain other solvents such as methanol and protonate molecules or ions, and can also serve as an acid-catalyst for chemical reactions where anhydrous (water-free) conditions are desired.
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Columbia College.A description of a similar demonstration which Tesla organized at the Westinghouse exhibit at the 1893 Columbian Exposition in St. Louis is found in The two metal sheets are connected to a Tesla coil oscillator, which applies a high radio frequency oscillating voltage. The oscillating electric field between the sheets ionizes the low pressure gas in the two long Geissler tubes he is holding, causing them to glow by fluorescence, similar to neon lights, without wires. A charismatic showman and self-promoter, in 1891-1893 Tesla used the Tesla coil in dramatic public lectures demonstrating the new science of high voltage, high frequency electricity.
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The chemistry of polonium is similar to that of tellurium, although it also shows some similarities to its neighbor bismuth due to its metallic character. Polonium dissolves readily in dilute acids but is only slightly soluble in alkalis. Polonium solutions are first colored in pink by the Po2+ ions, but then rapidly become yellow because alpha radiation from polonium ionizes the solvent and converts Po2+ into Po4+.As polonium also emits alpha-particles after disintegration so this process is accompanied by bubbling and emission of heat and light by glassware due to the absorbed alpha particles; as a result, polonium solutions are volatile and will evaporate within days unless sealed.
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After a certain time, the electron in an excited state will "jump" (undergo a transition) to a lower state. In a neutral atom, the system will emit a photon of the difference in energy, since energy is conserved. If an inner electron has absorbed more than the binding energy (so that the atom ionizes), then a more outer electron may undergo a transition to fill the inner orbital. In this case, a visible photon or a characteristic x-ray is emitted, or a phenomenon known as the Auger effect may take place, where the released energy is transferred to another bound electron, causing it to go into the continuum.
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The strength of an acid refers to its ability or tendency to lose a proton. A strong acid is one that completely dissociates in water; in other words, one mole of a strong acid HA dissolves in water yielding one mole of H+ and one mole of the conjugate base, A−, and none of the protonated acid HA. In contrast, a weak acid only partially dissociates and at equilibrium both the acid and the conjugate base are in solution. Examples of strong acids are hydrochloric acid (HCl), hydroiodic acid (HI), hydrobromic acid (HBr), perchloric acid (HClO4), nitric acid (HNO3) and sulfuric acid (H2SO4). In water each of these essentially ionizes 100%.
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Schematic of a Hall effect thruster Hall effect thrusters accelerate ions by means of an electric potential between a cylindrical anode and a negatively charged plasma that forms the cathode. The bulk of the propellant (typically xenon) is introduced near the anode, where it ionizes and flows toward the cathode; ions accelerate towards and through it, picking up electrons as they leave to neutralize the beam and leave the thruster at high velocity. The anode is at one end of a cylindrical tube. In the center is a spike that is wound to produce a radial magnetic field between it and the surrounding tube.
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Back at Granny's, Emma takes part of the Promethean Flame and ionizes it, before she thrusts both halves of Excalibur into the flame to reunite the blade. However, the cut from Excalibur that Hook received reappears, causing him to bleed and collapse. Emma catches holds him and tells him that she's not ready to let him go, but Hook tells her that it's okay and wants to see her reunite Excalibur before he dies. As Emma desperately searches for a way to save Hook, Merlin tells her that there's nothing she can do to heal a wound from Excalibur (which was forged to cut immortal ties), and Regina and Emma's parents tell her that Merlin's right.
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Thiols react with this compound, cleaving the disulfide bond to give 2-nitro-5-thiobenzoate (TNB−), which ionizes to the TNB2− dianion in water at neutral and alkaline pH. This TNB2− ion has a yellow color. :Reaction of DTNB with a thiol (R-SH). This reaction is rapid and stoichiometric, with the addition of one mole of thiol releasing one mole of TNB. The TNB2− is quantified in a spectrophotometer by measuring the absorbance of visible light at 412 nm, using an extinction coefficient of 14,150 M−1 cm−1 for dilute buffer solutions, and a coefficient of 13,700 M−1 cm−1 for high salt concentrations, such as 6 M guanidinium hydrochloride or 8 M urea.
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Visualisation of the spread of Townsend avalanches by means of UV photons Geiger-Müller tubes are the primary components of Geiger counters. They operate at an even higher voltage, selected such that each ion pair creates an avalanche, but by the emission of UV photons, multiple avalanches are created which spread along the anode wire, and the adjacent gas volume ionizes from as little as a single ion pair event. This is the "Geiger region" of operation. The current pulses produced by the ionising events are passed to processing electronics which can derive a visual display of count rate or radiation dose, and usually in the case of hand-held instruments, an audio device producing clicks.
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Ammonia fumes from aqueous ammonium hydroxide (in test tube) reacting with hydrochloric acid (in beaker) to produce ammonium chloride (white smoke). Bases react with acids to neutralize each other at a fast rate both in water and in alcohol. When dissolved in water, the strong base sodium hydroxide ionizes into hydroxide and sodium ions: :NaOH → + and similarly, in water the acid hydrogen chloride forms hydronium and chloride ions: :HCl + → + When the two solutions are mixed, the and ions combine to form water molecules: : + → 2 If equal quantities of NaOH and HCl are dissolved, the base and the acid neutralize exactly, leaving only NaCl, effectively table salt, in solution. Weak bases, such as baking soda or egg white, should be used to neutralize any acid spills.
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400px A key feature of the cofactor TPP is the relatively acidic proton bound to the carbon atom between the nitrogen and sulfur in the thiazole ring, which has a pKa near 10. This carbon center ionizes to form a carbanion, which adds to the carbonyl group of oxalyl-CoA. This addition is followed by the decarboxylation of oxalyl-CoA, and then the oxidation and removal of formyl-CoA to regenerate the carbanion form of TPP. While the reaction mechanism is shared with other TPP-dependent enzymes, the residues found in the active site of OXC are unique, which has raised questions about whether TDP must be deprotonated by a basic amino acid at a second site away from the carbanion-forming site to activate the cofactor.
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They are created after the red giant phase, when most of the outer layers of the star have been expelled by strong stellar winds Once all of the red giant's atmosphere has been dissipated, energetic ultraviolet radiation from the exposed hot luminous core, called a planetary nebula nucleus (PNN), ionizes the ejected material. Absorbed ultraviolet light then energizes the shell of nebulous gas around the central star, causing it to appear as a brightly coloured planetary nebula. Planetary nebulae likely play a crucial role in the chemical evolution of the Milky Way by expelling elements into the interstellar medium from stars where those elements were created. Planetary nebulae are observed in more distant galaxies, yielding useful information about their chemical abundances.
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The above peak voltage is only achieved in coils in which air discharges do not occur; in coils which produce sparks, like entertainment coils, the peak voltage on the terminal is limited to the voltage at which the air breaks down and becomes conductive. As the output voltage increases during each voltage pulse, it reaches the point where the air next to the high voltage terminal ionizes and corona, brush discharges and streamer arcs, break out from the terminal. This happens when the electric field strength exceeds the dielectric strength of the air, about 30 kV per centimeter. Since the electric field is greatest at sharp points and edges, air discharges start at these points on the high voltage terminal.
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During resonance ionization, an ion gun creates a cloud of atoms and molecules from a gas-phase sample surface and a tunable laser is used to fire a beam of photons at the cloud of particles emanating from the sample (analyte). An initial photon from this beam is absorbed by one of the sample atoms, exciting one of the atom's electrons to an intermediate excited state. A second photon then ionizes the same atom from the intermediate state such that its high energy level causes it to be ejected from its orbital; the result is a packet of positively charged ions which are then delivered to a mass analyzer. Resonance ionization contrasts with resonance-enhanced multiphoton ionization (REMPI) in that the latter is neither selective nor efficient since resonances are seldom used to prevent interference.
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Net electric charges on conductors, including local charge distributions associated with dipoles, reside entirely on their external surface (see Faraday cage), and tend to concentrate more around sharp points and edges than on flat surfaces. This means that the electric field generated by charges on a sharp conductive point is much stronger than the field generated by the same charge residing on a large smooth spherical conductive shell. When this electric field strength exceeds what is known as the corona discharge inception voltage (CIV) gradient, it ionizes the air about the tip, and a small faint purple jet of plasma can be seen in the dark on the conductive tip. Ionization of the nearby air molecules result in generation of ionized air molecules having the same polarity as that of the charged tip.
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The collapsing cloud region will undergo hierarchical fragmentation into ever smaller clumps, including a particularly dense form known as infrared dark clouds, eventually leading to the formation of up to several thousand stars. This star formation begins enshrouded in the collapsing cloud, blocking the protostars from sight but allowing infrared observation. In the Milky Way galaxy, the formation rate of open clusters is estimated to be one every few thousand years. The so-called "Pillars of Creation", a region of the Eagle Nebula where the molecular cloud is being evaporated by young, massive stars The hottest and most massive of the newly formed stars (known as OB stars) will emit intense ultraviolet radiation, which steadily ionizes the surrounding gas of the giant molecular cloud, forming an H II region.
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The heat generated by the arc and electrodes then ionizes the mercury and metal halides into a plasma, which produces an increasingly-brighter harsh white light as the temperature and pressure increases to operating conditions. The arc-tube operates at anywhere from 5–50 atm or more (70–700 psi or 500–5000 kPa) and 1000–3000 °C. Like all other gas-discharge lamps, metal-halide lamps have negative resistance (with the rare exception of self-ballasted lamps with a filament), and so require a ballast to provide proper starting and operating voltages while regulating the current flow through the lamp. About 24% of the energy used by metal-halide lamps produces light (an efficacy of 65–115 lm/W), making them substantially more efficient than incandescent bulbs, which typically have efficiencies in the range 2–4%.
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The helicon drive produces a tight beam of ions as the magnetic field that accelerates them continuously expands with the plasma beam keeping them focused. This ion beam is used to push a payload which is equipped with a small amount of gas for propellant such as argon or xenon, a power source and a set of electromagnets to produce a mini- magnetosphere magnetic sail. The gas propellant is ejected into the plasma beam being directed at the craft which heats and ionizes it. The electromagnets repel this ionized gas imparting thrust upon the payload. This results in an acceleration of around 1 ms−2, much faster than traditional ion propulsion systems. This amount of acceleration would make it possible to make a trip to Mars in as little as 50 days, reaching speeds as high as 20 km/s.
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Various types of glow starter A glow switch starter or glowbottle starter is a type of preheat starter used with a fluorescent lamp. It is commonly filled with neon gas or argon gas and contains a bimetallic strip and a stationary electrode. The operating principle is simple, when current is applied, the gas inside ionizes and heats a bimetallic strip which in turn bends toward the stationary electrode thus shorting the starter between the electrodes of the fluorescent lamp After a second the starter's bimetallic strip will cool and open the circuit between the electrodes and the process repeats until the lamp has lit. One disadvantage of glow switch starters is that when the lamp is at the end of its life it will continuously blink on and off until the glow switch starter wears out or an electrode on the fluorescent lamp burns out.
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Schematic of a typical dynamic SIMS instrument. High energy (usually several keV) ions are supplied by an ion gun (1 or 2) and focused on to the target sample (3), which ionizes and sputters some atoms off the surface (4). These secondary ions are then collected by ion lenses (5) and filtered according to atomic mass (6), then projected onto an electron multiplier (7, top), Faraday cup (7, bottom), or CCD screen (8). A secondary ion mass spectrometer consists of (1) a primary ion gun generating the primary ion beam, (2) a primary ion column, accelerating and focusing the beam onto the sample (and in some devices an opportunity to separate the primary ion species by Wien filter or to pulse the beam), (3) high vacuum sample chamber holding the sample and the secondary ion extraction lens, (4) a mass analyser separating the ions according to their mass-to-charge ratio, and (5) a detector.
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