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RRW
The Reliable Replacement Warhead (RRW) was a proposed new American nuclear warhead design and bomb family that was intended to be simple, reliable and to provide a long-lasting, low-maintenance future nuclear force for the United States. Initiated by the United States Congress in 2004, it became a centerpiece of the plans of the National Nuclear Security Administration (NNSA) to remake the nuclear weapons complex. In 2008, Congress denied funding for the program, and in 2009 the Obama administration called for work on the program to cease. Background During the Cold War, the United States, in an effort to achieve and maintain an advantage in the nuclear arms race with the Soviet Union, invested large amounts of money and technical resources into nuclear weapons design, testing, and maintenance. Many of the weapons designed required high upkeep costs, justified primarily by their Cold War context and the specific and technically sophisticated applications they were created for. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lawrence Livermore National Laboratory
Lawrence Livermore National Laboratory (LLNL) is a federal research facility in Livermore, California, United States. The lab was originally established as the University of California Radiation Laboratory, Livermore Branch in 1952 in response to the detonation of the first atomic bomb by the Soviet Union during the Cold War. It later became autonomous in 1971 and was designated a national laboratory in 1981. A federally funded research and development center, Lawrence Livermore Lab is primarily funded by the U.S. Department of Energy and it is managed privately and operated by Lawrence Livermore National Security, LLC (a partnership of the University of California), Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium (element 116) named after it. Overview LLNL is self-described as a "premier research and development institution for sci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teller-Ulam Design
A thermonuclear weapon, fusion weapon or hydrogen bomb (H bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a lower mass, or a combination of these benefits. Characteristics of nuclear fusion reactions make possible the use of non-fissile depleted uranium as the weapon's main fuel, thus allowing more efficient use of scarce fissile material such as uranium-235 () or plutonium-239 (). The first full-scale thermonuclear test was carried out by the United States in 1952; the concept has since been employed by most of the world's nuclear powers in the design of their weapons. Modern fusion weapons consist essentially of two main components: a nuclear fission primary stage (fueled by or ) and a separate nuclear fusion secondary stage containing thermonuclear fuel: the heavy hydrogen isotopes deuterium and tritium, or in modern weapons lithium deuteride. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Bomb
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or a combination of fission and fusion reactions (thermonuclear bomb), producing a nuclear explosion. Both bomb types release large quantities of energy from relatively small amounts of matter. The first test of a fission ("atomic") bomb released an amount of energy approximately equal to . The first thermonuclear ("hydrogen") bomb test released energy approximately equal to . Nuclear bombs have had yields between 10 tons TNT (the W54) and 50 megatons for the Tsar Bomba (see TNT equivalent). A thermonuclear weapon weighing as little as can release energy equal to more than . A nuclear device no larger than a conventional bomb can devastate an entire city by blast, fire, and radiation. Since they are weapons of mass destruction, the proliferation of nuclear weapons is a focus of international relations policy. Nuclear weapons have been deployed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium
Plutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric. It is radioactive and can accumulate in bones, which makes the handling of plutonium dangerous. Plutonium was first synthetically produced and isolated in late 1940 and early 1941, by a deuteron bombardment of uranium-238 in the cyclotron at the University of California, Berkeley. First, neptunium-238 ( half-life 2.1 days) was synthesized, which subsequently beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years). Since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadium
Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer ( passivation) somewhat stabilizes the free metal against further oxidation. Spanish scientist Andrés Manuel del Río discovered compounds of vanadium in 1801 in Mexico by analyzing a new lead-bearing mineral he called "brown lead". Though he initially presumed its qualities were due to the presence of a new element, he was later erroneously convinced by French chemist Hippolyte Victor Collet-Descotils that the element was just chromium. Then in 1830, Nils Gabriel Sefström generated chlorides of vanadium, thus proving there was a new element, and named it "vanadium" after the Scandinavian goddess of beauty and fertility, Vanadís (Freyja). The name was based on the wide range of colors found in vanadium compounds. Del Rio's lead mineral was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Bunker Buster
A nuclear bunker buster, also known as an earth-penetrating weapon (EPW), is the nuclear equivalent of the conventional bunker buster. The non-nuclear component of the weapon is designed to penetrate soil, rock, or concrete to deliver a nuclear warhead to an underground target. These weapons would be used to destroy hardened, underground military bunkers or other below-ground facilities. An underground explosion releases a larger fraction of its energy into the ground, compared to a surface burst or air burst explosion at or above the surface, and so can destroy an underground target using a lower explosive yield. This in turn could lead to a reduced amount of radioactive fallout. However, it is unlikely that the explosion would be completely contained underground. As a result, significant amounts of rock and soil would be rendered radioactive and lofted as dust or vapor into the atmosphere, generating significant fallout. Base principle While conventional bunker busters use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Little Boy
"Little Boy" was the type of atomic bomb dropped on the Japanese city of Hiroshima on 6 August 1945 during World War II, making it the first nuclear weapon used in warfare. The bomb was dropped by the Boeing B-29 Superfortress ''Enola Gay'' piloted by Colonel Paul W. Tibbets, Jr., commander of the 509th Composite Group of the United States Army Air Forces and Captain Robert A. Lewis. It exploded with an energy of approximately and caused widespread death and destruction throughout the city. The Hiroshima bombing was the second man-made nuclear explosion in history, after the Trinity nuclear test. Little Boy was developed by Lieutenant Commander Francis Birch (geophysicist), Francis Birch's group at the Manhattan Project's Los Alamos Laboratory during World War II, a reworking of their unsuccessful Thin Man (nuclear bomb), Thin Man nuclear bomb. Like Thin Man, it was a gun-type fission weapon, but it derived its explosive power from the nuclear fission of uranium-235, where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastic Bonded Explosive
Polymer-bonded explosives, also called PBX or plastic-bonded explosives, are explosive materials in which explosive powder is bound together in a matrix using small quantities (typically 5–10% by weight) of a synthetic polymer. PBXs are normally used for explosive materials that are not easily melted into a casting, or are otherwise difficult to form. PBX was first developed in 1952 at Los Alamos National Laboratory, as RDX embedded in polystyrene with dioctyl phthalate plasticizer. HMX compositions with teflon-based binders were developed in 1960s and 1970s for gun shells and for Apollo Lunar Surface Experiments Package (ALSEP) seismic experiments, although the latter experiments are usually cited as using hexanitrostilbene (HNS). Potential advantages Polymer-bonded explosives have several potential advantages: * If the polymer matrix is an elastomer (rubbery material), it tends to absorb shocks, making the PBX very insensitive to accidental detonation, and thus ideal for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TATB
TATB, triaminotrinitrobenzene or 2,4,6-triamino-1,3,5-trinitrobenzene is an aromatic explosive, based on the basic six-carbon benzene ring structure with three nitro functional groups (NO2) and three amine (NH2) groups attached, alternating around the ring. TATB is a very powerful explosive (somewhat less powerful than RDX, but more than TNT), but it is extremely insensitive to shock, vibration, fire, or impact. Because it is so difficult to detonate by accident, even under severe conditions, it has become preferred for applications where extreme safety is required, such as the explosives used in nuclear weapons, where accidental detonation during an airplane crash or rocket misfiring would present extreme dangers. All British nuclear warheads use TATB-based explosives in their primary stage. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium Pit
Plutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric. It is radioactive and can accumulate in bones, which makes the handling of plutonium dangerous. Plutonium was first synthetically produced and isolated in late 1940 and early 1941, by a deuteron bombardment of uranium-238 in the cyclotron at the University of California, Berkeley. First, neptunium-238 (half-life 2.1 days) was synthesized, which subsequently beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years). Since uranium ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JASON (advisory Group)
JASON is an independent group of elite scientists which advises the United States government on matters of science and technology, mostly of a sensitive nature. The group was created in the aftermath of the Sputnik launch as a way to reinvigorate the idea of having the nation's preeminent scientists help the government with defense problems, similar to the way that scientists helped in World War II but with a new and younger generation. It was established in 1960 and has somewhere between 30 and 60 members. Its work first gained public notoriety as the source of the Vietnam War's McNamara Line electronic barrier. Although most of its research is military-focused, JASON also produced early work on the science of global warming and acid rain. Current unclassified research interests include health informatics, cyberwarfare, and renewable energy. Activities For administrative purposes, JASON's activities are run through the MITRE Corporation, a not-for-profit corporation in McLean, V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aging (material Science)
Precipitation hardening, also called age hardening or particle hardening, is a heat treatment technique used to increase the yield strength of malleable materials, including most structural alloys of aluminium, magnesium, nickel, titanium, and some steels and stainless steels. In superalloys, it is known to cause yield strength anomaly providing excellent high-temperature strength. Precipitation hardening relies on changes in solid solubility with temperature to produce fine particles of an impurity phase, which impede the movement of dislocations, or defects in a crystal's lattice. Since dislocations are often the dominant carriers of plasticity, this serves to harden the material. The impurities play the same role as the particle substances in particle-reinforced composite materials. Just as the formation of ice in air can produce clouds, snow, or hail, depending upon the thermal history of a given portion of the atmosphere, precipitation in solids can produce many different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
