FACTOID # 21: 15% of Army recruits from South Dakota are Native American, which is roughly the same percentage for female Army recruits in the state.

 Home Encyclopedia Statistics States A-Z Flags Maps FAQ About

 WHAT'S NEW RELATED ARTICLES People who viewed "Tritium" also viewed:

SEARCH ALL

Search encyclopedia, statistics and forums:

(* = Graphable)

Encyclopedia > Tritium
Tritium

Tritium Download high resolution version (730x685, 11 KB) Tritium Created by oo64eva using Macromedia Fireworks 4. ...

General
Name, symbol tritium, triton,3H
Neutrons 2
Protons 1
Nuclide data
Natural abundance trace
Half-life 12.32 years
Decay products 3He
Isotope mass 3.0160492 u
Spin 1/2+
Excess energy 14949.794± 0.001 keV
Binding energy 8481.821± 0.004 keV
Decay mode Decay energy
Beta emission 0.018590 MeV

Tritium is radioactive with a half-life of 12.32 years. It decays into helium-3 by the reaction Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... Helium-3 is a non-radioactive and light isotope of helium. ...

${}^3_1hbox{H}to{}^3_2hbox{He}^++hbox{e}^-+overline{nu}_{hbox{e}}$

releasing 18.6 keV of energy. The electron has an average kinetic energy of 5.7 keV, while the remaining energy is carried off by the nearly undetectable electron antineutrino. The low-energy beta radiation from tritium cannot penetrate human skin, so tritium is only dangerous if inhaled or ingested. Its low energy also creates difficulty detecting tritium labelled compounds except by using liquid scintillation counting. Kev can refer to either: A regional term for the chav social group in the United Kingdom An abbreviation - keV - of the unit Kiloelectronvolt An abbreviation for the given name Kevin. ... For other uses, see Electron (disambiguation). ... An antineutrino is the antimatter equivalent particle of the neutrino. ... Beta particles are high-energy electrons emitted by certain types of radioactive nuclei such as potassium-40. ... Liquid scintillation counting is a standard laboratory method in the life-sciences for measuring radiation from beta-emitting nuclides. ...

## Contents

Tritium occurs naturally due to cosmic rays interacting with atmospheric gases. In the most important reaction for natural tritium production, a fast neutron (>4MeV [1]) interacts with atmospheric nitrogen: Cosmic rays can loosely be defined as energetic particles originating outside of the Earth. ... A fast neutron is a free neutron with a kinetic energy level close to 1 MeV (10 TJ/kg, hence a speed of 14,000 km/s. ... An electronvolt (symbol: eV) is the amount of energy gained by a single unbound electron when it falls through an electrostatic potential difference of one volt. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ...

${}^{14}_7hbox{N}+{}^1hbox{n}to{}^{12}_6hbox{C}+{}^3_1hbox{H}$

Because of tritium's relatively short half-life, however, tritium produced in this manner does not accumulate over geological timescales, and its natural abundance is negligible.

Industrially, tritium is produced in nuclear reactors by neutron activation of lithium-6. Nuclear power station at Leibstadt, Switzerland. ... Neutron activation is the process by which neutron radiation induces radioactivity in materials. ... General Name, Symbol, Number lithium, Li, 3 Chemical series alkali metals Group, Period, Block 1, 2, s Appearance silvery white/gray Atomic mass 6. ...

${}^6_3hbox{Li}+{}^1hbox{n}to{}^4_2hbox{He}+{}^3_1hbox{H}$

High-energy neutrons can also produce tritium from lithium-7. This was discovered when the 1954 Castle Bravo nuclear test produced an unexpectedly high yield. General Name, Symbol, Number Lithium, Li, 3 Series Alkali metal Group, Period, Block 1(IA), 2, s Density, Hardness 535 kg/m3, 0. ... A black-and-white photograph of the Castle Bravo mushroom cloud. ...

${}^7_3hbox{Li}+{}^1hbox{n}to{}^4_2hbox{He}+{}^3_1hbox{H}+{}^1hbox{n}$

[2].

Tritium can also be produced from boron-10 through neutron capture. For other uses, see Boron (disambiguation). ... The process of neutron capture can proceed in two ways - as a rapid process (an r-process) or a slow process (an s-process). ...

${}^{10}_5hbox{B}+{}^1hbox{n}to{}^4_2hbox{He}+{}^4_2hbox{He}+{}^3_1hbox{H}$

Tritium's decay product helium-3 has a very large cross section for the (n,p) reaction and is rapidly converted back to tritium in a nuclear reactor. Helium-3 is a non-radioactive and light isotope of helium. ...

${}^3_2hbox{He}+{}^1hbox{n}to{}^1_1hbox{H}+{}^3_1hbox{H}$

Tritium is occasionally a direct product of nuclear fission, with a yield of about 0.01% (one per 10000 fissions). [3][4] This means that tritium release or recovery needs to be considered in nuclear reprocessing even in ordinary spent nuclear fuel where tritium production was not a goal. For the generation of electrical power by fission, see Nuclear power plant. ... // Nuclear reprocessing separates any usable elements (e. ... Spent nuclear fuel, occasionally called used nuclear fuel, is nuclear fuel that has been irradiated in a nuclear reactor (usually at a nuclear power plant) to the point where it is no longer useful in sustaining a nuclear reaction. ...

Tritium is also produced in heavy water-moderated reactors when deuterium captures a neutron, but this reaction has a small cross section. Heavy water is dideuterium oxide, or D2O or 2H2O. It is chemically the same as normal water, H2O, but the hydrogen atoms are of the heavy isotope deuterium, in which the nucleus contains a neutron in addition to the proton found in the nucleus of any hydrogen atom. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ... In nuclear and particle physics, the concept of a cross section is used to express the likelihood of interaction between particles. ...

According to IEER's 1996 report about the United States Department of Energy, only 225 kg of tritium has been produced in the US since 1955. Since it is continuously decaying into helium-3, the stockpile was estimated as approximately 75 kg at the time of the report [5]. The Institute for Energy and Environmental Research (IEER) is a Washington, D.C.-area American policy organization (think tank) located in Takoma Park, Maryland. ... The United States Department of Energy (DOE) is a Cabinet-level department of the United States government responsible for energy policy and nuclear safety. ...

## Properties

Tritium figures prominently in studies of nuclear fusion due to its favorable reaction cross section and the high energy yield of 17.6 MeV for its reaction with deuterium: The deuterium-tritium (D-T) fusion reaction is considered the most promising for producing fusion power. ... In nuclear and particle physics, the concept of a cross section is used to express the likelihood of interaction between particles. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ...

${}^3_1hbox{H}+{}^2_1hbox{D}to{}^4_2hbox{He}+hbox{n}$

All atomic nuclei, being composed of protons and neutrons, repel one another because of their positive charge. However, if the atoms have a high enough temperature and pressure (as is the case in the core of the Sun, for example), then their random motions can overcome such electrical repulsion (called the Coulomb force), and they can come close enough for the strong nuclear force to take effect, fusing them into heavier atoms. Since tritium has the same charge as ordinary hydrogen, it experiences the same electrostatic repulsive force (see Coulomb's law). However, due to tritium's supply of neutrons which are carried into reactions and feel the attractive strong force once delivered, tritium can more easily fuse with other light atoms. The same is also true, albeit to a lesser extent, of deuterium, and that is why brown dwarfs (so-called failed stars) can not burn hydrogen, but do indeed burn deuterium. This box:      Coulombs torsion balance Coulombs law, developed in the 1780s by French physicist Charles Augustin de Coulomb, may be stated in scalar form as follows: The magnitude of the electrostatic force between two point electric charges is directly proportional to the product of the magnitudes of each... The strong nuclear force or strong interaction (also called color force or colour force) is a fundamental force of nature which affects only quarks and antiquarks, and is mediated by gluons in a similar fashion to how the electromagnetic force is mediated by photons. ... This box:      Coulombs torsion balance Coulombs law, developed in the 1780s by French physicist Charles Augustin de Coulomb, may be stated in scalar form as follows: The magnitude of the electrostatic force between two point electric charges is directly proportional to the product of the magnitudes of each... This brown dwarf (smaller object) orbits the star Gliese 229, which is located in the constellation Lepus about 19 light years from Earth. ... This article is about the astronomical object. ...

Radioluminescent 1.2 Curie 4" x .2" Tritium vials are simply tritium gas filled thin glass vials whose inner surfaces are coated with a phosphor. The "gaseous tritium light source" vial shown here is 1.5 years old.

Before the onset of atmospheric nuclear weapons tests, the global equilibrium tritium inventory was estimated at about 80 megacuries (MCi). Image File history File links Trtium. ... Image File history File links Trtium. ... Radioluminescent 1. ... Green screen A phosphor is a substance that exhibits the phenomenon of phosphorescence (sustained glowing after exposure to light or energised particles such as electrons). ...

Atmospheric nuclear testing (prior to the Partial Test Ban Treaty) proved unexpectedly useful to oceanographers, as the sharp spike in surface tritium levels could be used over the years to measure the rate at which the lower and upper ocean levels mixed. The Treaty Banning poop, in Outer Space, and Under Water, often abbreviated as the Partial Test Ban Treaty (PTBT), Limited Test Ban Treaty (LTBT), or Nuclear Test Ban Treaty (NTBT), although the former also refers to the Comprehensive Test Ban Treaty (CTBT), is a treaty intended to obtain an agreement...

## Regulatory limits

The legal limits for tritium in drinking water can vary. The U.S. limit is calculated to yield a dose of 4 mrem (or 40 microsieverts in SI units) per year. Tap water Mineral Water Drinking water is water that is intended to be ingested through drinking by humans. ... The rÃ¶ntgen (roentgen) equivalent in man or rem (symbol rem) is a unit of radiation dose. ... The sievert (symbol: Sv) is the SI derived unit of dose equivalent. ... The International System of Units (symbol: SI) (for the French phrase Système International dUnités) is the most widely used system of units. ...

For other uses, see Becquerel (disambiguation). ... For other uses, see Becquerel (disambiguation). ... The curie (symbol Ci) is a former unit of radioactivity, defined as 3. ... The Safe Drinking Water Act was an act passed by Congress on December 16, 1974. ... For other uses, see Becquerel (disambiguation). ...

## Usage

### Self-powered lighting

A tritium illuminated watch face

The aforementioned IEER report claims that the commercial demand for tritium is 400 grams per year. The Institute for Energy and Environmental Research (IEER) is a Washington, D.C.-area American policy organization (think tank) located in Takoma Park, Maryland. ...

### Nuclear weapons

Tritium is widely used in nuclear weapons for boosting a fission bomb or the fission primary of a thermonuclear weapon. Before detonation, a few grams of tritium-deuterium gas are injected into the hollow "pit" of fissile plutonium or uranium. The early stages of the fission chain reaction supply enough heat and compression to start DT fusion, then both fission and fusion proceed in parallel, the fission assisting the fusion by continuing heating and compression, and the fusion assisting the fission with highly energetic (14.1 MeV) neutrons. As the fission fuel depletes and also explodes outward, it falls below the density needed to stay critical by itself, but the fusion neutrons make the fission process progress faster and continue longer than it would without boosting. Increased yield comes overwhelmingly from the increase in fission; the energy released by the fusion itself is much smaller because the amount of fusion fuel is much smaller. The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter A nuclear weapon derives its destructive force from nuclear reactions of fusion or fission. ... Boosted fission weapons are a type of nuclear bomb that uses a small amount of fusion fuel to increase the rate, and thus yield, of a fission reaction. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, in 1945 lifted nuclear fallout some 18 km (60,000 feet) above the epicenter. ... An electronvolt (symbol: eV) is the amount of energy gained by a single unbound electron when it falls through an electrostatic potential difference of one volt. ...

Besides increased yield (for the same amount of fission fuel with vs. without boosting) and the possibility of variable yield (by varying the amount of fusion fuel), possibly even more important advantages are allowing the weapon (or primary of a weapon) to have a smaller amount of fissile material (eliminating the risk of predetonation by nearby nuclear explosions) and more relaxed requirements for implosion, allowing a smaller implosion system. Variable yield, or Dial-a-yield, an option available on most modern nuclear bombs, allows the operator to specify a bombs yield, or explosive power, allowing a single design to be used in different situations. ...

Because the tritium in the warhead is continuously decaying, it is necessary to replenish it periodically. The estimated quantity needed is 4 grams per warhead.[1] To maintain constant inventory, 0.22 grams per warhead per year must be produced. A B61 nuclear bomb in various stages of assembly; the nuclear warhead is the bullet-shaped silver cannister in the middle-left of the photograph. ...

As tritium quickly decays and is difficult to contain, the much larger secondary charge of a thermonuclear weapon instead uses lithium deuteride as its fusion fuel; during detonation, neutrons split lithium-6 into helium-4 and tritium; the tritium then fuses with deuterium, producing more neutrons. As this process requires a higher temperature for ignition, and produces fewer and less energetic neutrons (only D-D fusion and 7Li splitting are net neutron producers), LiD is not used for boosting, only for secondaries. Lithium hydride (LiH) (also known as Lithium deuteride, when the deuterium isotope of hydrogen is used for the hydrogen component) is a compound of lithium and hydrogen. ... General Name, Symbol, Number lithium, Li, 3 Chemical series alkali metals Group, Period, Block 1, 2, s Appearance silvery white/gray Atomic mass 6. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ...

Main article: nuclear weapon design

The first nuclear weapons, though large, cumbersome and inefficient, provided the basic design building blocks of all future weapons. ...

### Controlled nuclear fusion

Tritium is an important fuel for controlled nuclear fusion in both magnetic confinement and inertial confinement fusion reactor designs. The experimental fusion reactor ITER and the National Ignition Facility (NIF) will use Deuterium-Tritium (D-T) fuel. The D-T reaction is favored since it has the largest fusion cross-section (~ 5 barns peak) and reaches this maximum cross-section at the lowest energy (~65 keV center-of-mass) of any potential fusion fuel. The deuterium-tritium (D-T) fusion reaction is considered the most promising for producing fusion power. ... Magnetic Fusion Energy (MFE) is a sustained nuclear fusion reaction in a plasma that is contained by magnetic fields. ... Inertial confinement fusion using lasers rapidly progressed in the late 1970s and early 1980s from being able to deliver only a few joules of laser energy (per pulse) to a fusion target to being able to deliver tens of kilojoules to a target. ... ITER is an international tokamak (magnetic confinement fusion) research/engineering project designed to prove the scientific and technological feasibility of a full-scale fusion power reactor. ... A construction worker inside NIFs 10 meter target chamber. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ... Internal view of the JET tokamak superimposed with an image of a plasma taken with a visible spectrum video camera. ... In nuclear and particle physics, the concept of a cross section is used to express the likelihood of interaction between particles. ... A barn (symbol b) is a unit of area. ... The electronvolt (symbol eV) is a unit of energy. ...

## History

Tritium was first predicted in the late 1920s by Walter Russell, using his "spiral" periodic table[citation needed], then produced in 1934 from deuterium, another isotope of hydrogen, by Ernest Rutherford, working with Mark Oliphant and Paul Harteck. Rutherford was unable to isolate the tritium, a job that was left to Luis Alvarez and Robert Cornog, who correctly deduced that the substance was radioactive. Willard F. Libby discovered that tritium could be used for dating water, and therefore wine. Walter Russell (1871â€“1963), is an American artist, sculptor, architect, and a controversial figure in physics and cosmogony, credited as the originator of the term New Age. He posited that the universe was founded on the unifying principle of rhythmic balanced interchange. ... Year 1934 (MCMXXXIV) was a common year starting on Monday (link will display full 1934 calendar) of the Gregorian calendar. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ... Ernest Rutherford, 1st Baron Rutherford of Nelson OM PC FRS (30 August 1871 - 19 October 1937), widely referred to as Lord Rutherford, was a nuclear physicist who became known as the father of nuclear physics. ... Sir Marcus Mark Laurence Elwin Oliphant AC KBE (October 8, 1901 â€“ July 14, 2000) was an Australian physicist and humanitarian who played a fundamental role in the development of the Atomic bomb. ... Paul Karl Maria Harteck (20 July 1902 in Vienna, Austria â€“ 22 January 1985 in Santa Barbara, California) was a German physical chemist. ... Portrait of Luis Alvarez Luis Walter Alvarez (June 13, 1911 â€“ September 1, 1988) of San Francisco, California, USA, was a famed physicist of Spanish descent, who worked at the University of California, Berkeley. ... Robert Alden Cornog (1912-1998), was a physicist and engineer who helped develop the atomic bomb and missile systems from the Snark to the Minuteman. ... Willard Frank Libby (December 17, 1908 &#8211; September 8, 1980) was an American chemist, famous for his role in the development of radiocarbon dating, a process which revolutionised archaeology. ... Radiometric dating (often called radioactive dating) is a technique used to date materials, based on a comparison between the observed abundance of particular naturally occurring radioactive isotopes and their known decay rates. ... For other uses, see Wine (disambiguation). ...

Results from FactBites:

 Tritium - Wikipedia, the free encyclopedia (805 words) Tritium is also produced in heavy water-moderated reactors when deuterium captures a neutron; however, this reaction has a much smaller cross section and is only a useful tritium source for a reactor with a very high neutron flux. This has raised concerns that if tritium is used in quantity, in particular for fusion reactors, it may contribute to radioactive contamination, although its short half-life should prevent any significant accumulation in the atmosphere. Tritium was first predicted in the late 1920s by Walter Russell, using his "spiral" periodic table, then produced in 1934 from deuterium, another isotope of hydrogen, by Ernest Rutherford, working with Mark Oliphant and Paul Harteck.
More results at FactBites »

Share your thoughts, questions and commentary here