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Explosive Lens
An explosive lens—as used, for example, in nuclear weapons—is a highly specialized shaped charge. In general, it is a device composed of several explosive charges. These charges are arranged and formed with the intent to control the shape of the detonation wave passing through them. The explosive lens is conceptually similar to an optical lens, which focuses light waves. The charges that make up the explosive lens are chosen to have different rates of detonation. In order to convert a spherically expanding wavefront into a spherically converging one using only a single boundary between the constituent explosives, the boundary shape must be a paraboloid; similarly, to convert a spherically diverging front into a flat one, the boundary shape must be a hyperboloid, and so on. Several boundaries can be used to reduce aberrations (deviations from intended shape) of the final wavefront. Invention As mentioned by Hans Bethe, the invention of the explosive lens device was contribu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modern HE Lenses
Modern may refer to: History * Modern history ** Early Modern period ** Late Modern period *** 18th century *** 19th century *** 20th century ** Contemporary history * Moderns, a faction of Freemasonry that existed in the 18th century Philosophy and sociology * Modernity, a loosely defined concept delineating a number of societal, economic and ideological features that contrast with "pre-modern" times or societies ** Late modernity Art * Modernism ** Modernist poetry * Modern art, a form of art * Modern dance, a dance form developed in the early 20th century * Modern architecture, a broad movement and period in architectural history * Modern music (other) Geography *Modra, a Slovak city, referred to in the German language as "Modern" Typography * Modern (typeface), a raster font packaged with Windows XP * Another name for the typeface classification known as Didone (typography) * Modern, a generic font family name for fixed-pitch serif and sans serif fonts ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Explosive Velocity
Explosive velocity, also known as detonation velocity or velocity of detonation (VoD), is the velocity at which the shock wave front travels through a detonated explosive. Explosive velocities are always faster than the local speed of sound in the material. If the explosive is confined before detonation, such as in an artillery shell, the force produced is focused on a much smaller area, and the pressure is significantly intensified. This results in an explosive velocity that is higher than if the explosive had been detonated in open air. Unconfined velocities are often approximately 70 to 80 percent of confined velocities. Explosive velocity is increased with smaller particle size (i.e., increased spatial density), increased charge diameter, and increased confinement (i.e., higher pressure). Typical detonation velocities for organic dust mixtures range from 1400–1650m/s. Gas explosions can either deflagrate or detonate based on confinement; detonation velocities are generall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swan (nuclear Primary)
Swan was a United States test nuclear explosive, which was developed into the XW-45 warhead.http://nuclearweaponarchive.org/Usa/Tests/Redwing.html "Inca .. Yield: 15.2 kt. UCRL test of a multi-application boosted tactical nuclear warhead prototype named Swan. This design was later developed into the XW-45 warhead. The predicted yield was 10-15 kt." It was tested standalone on June 22, 1956 in shot Redwing Inca. It was tested again as the primary of a thermonuclear device on July 2, 1956 in shot Redwing Mohawk.http://nuclearweaponarchive.org/Usa/Tests/Redwing.html "Mohawk. Yield: 360 kt This UCRL thermonuclear device used a boosted "Swan" primary and "Flute" secondary. The device was 15 inches in diameter, 46.2 inches long, and weighed 1116 lb. The primary was 11.6 inches by 22.8 inches and weighed 105 lb." Both tests were successful. Design features The Swan device is the first design to incorporate a two-point ignition hollow-pit air-lens implosion assembly together with fusi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RaLa Experiment
The RaLa Experiment, or RaLa, was a series of tests during and after the Manhattan Project designed to study the behavior of converging shock waves to achieve the spherical implosion necessary for compression of the plutonium pit of the nuclear weapon. The experiment used significant amounts of a short-lived radioisotope lanthanum-140, a potent source of gamma radiation; the RaLa is a contraction of Radioactive Lanthanum. The method was proposed by Robert Serber and developed by a team led by the Italian experimental physicist Bruno Rossi. The tests were performed with 1/8 inch (3.2 mm) spheres of radioactive lanthanum, equal to about and later , located in the center of a simulated nuclear device. The explosive lenses were designed primarily using this series of tests. Some 254 tests were conducted between September 1944 and March 1962. In his history of the Los Alamos project, David Hawkins wrote: “RaLa became the most important single experiment affecting the final bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manhattan Project
The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the United States Army Corps of Engineers, U.S. Army Corps of Engineers. Nuclear physicist Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the actual bombs. The Army component of the project was designated the Manhattan District as its first headquarters were in Manhattan; the placename gradually superseded the official codename, Development of Substitute Materials, for the entire project. Along the way, the project absorbed its earlier British counterpart, Tube Alloys. The Manhattan Project began modestly in 1939, but grew to employ more than 130,000 people and cost nearly US$2 billion (equivalent to about $ billion in ). Over 90 percent of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shock Wave
In physics, a shock wave (also spelled shockwave), or shock, is a type of propagating disturbance that moves faster than the local speed of sound in the medium. Like an ordinary wave, a shock wave carries energy and can propagate through a medium but is characterized by an abrupt, nearly discontinuous, change in pressure, temperature, and density of the medium. For the purpose of comparison, in supersonic flows, additional increased expansion may be achieved through an expansion fan, also known as a Prandtl–Meyer expansion fan. The accompanying expansion wave may approach and eventually collide and recombine with the shock wave, creating a process of destructive interference. The sonic boom associated with the passage of a supersonic aircraft is a type of sound wave produced by constructive interference. Unlike solitons (another kind of nonlinear wave), the energy and speed of a shock wave alone dissipates relatively quickly with distance. When a shock wave passes through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exploding-bridgewire Detonator
The exploding-bridgewire detonator (EBW, also known as exploding wire detonator) is a type of detonator used to initiate the detonation reaction in explosive materials, similar to a blasting cap because it is fired using an electric current. EBWs use a different physical mechanism than blasting caps, using more electricity delivered much more rapidly, and explode in a much more precise timing after the electric current is applied, by the process of exploding wire method. This has led to their common use in nuclear weapons. The slapper detonator is a more recent development along similar lines. History The EBW was invented by Luis Alvarez and Lawrence Johnston for the Fat Man–type bombs of the Manhattan Project, during their work in Los Alamos National Laboratory. The Fat Man Model 1773 EBW detonators used an unusual, high reliability detonator system with two EBW "horns" attached to a single booster charge, which then fired each of the 32 explosive lens units. Desc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphere
A sphere () is a Geometry, geometrical object that is a solid geometry, three-dimensional analogue to a two-dimensional circle. A sphere is the Locus (mathematics), set of points that are all at the same distance from a given point in three-dimensional space.. That given point is the centre (geometry), centre of the sphere, and is the sphere's radius. The earliest known mentions of spheres appear in the work of the Greek mathematics, ancient Greek mathematicians. The sphere is a fundamental object in many fields of mathematics. Spheres and nearly-spherical shapes also appear in nature and industry. Bubble (physics), Bubbles such as soap bubbles take a spherical shape in equilibrium. spherical Earth, The Earth is often approximated as a sphere in geography, and the celestial sphere is an important concept in astronomy. Manufactured items including pressure vessels and most curved mirrors and lenses are based on spheres. Spheres rolling, roll smoothly in any direction, so mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composition B
Composition B, colloquially Comp B, is an explosive consisting of castable mixtures of RDX and TNT. It is used as the main explosive filling in artillery projectiles, rockets, land mines, hand grenades and various other munitions. It was also used for the explosive lenses in the first implosion-type nuclear weapons developed by the United States.''Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man'', John Coster-Mullen, 2003Nuclear Weapons FAQ section 8.1.1: The Design of Gadget, Fat Man, and "Joe 1" (RDS-1) accessed August 10, 2009 The standard proportions of ingredients (by weight) are 59.5% RDX ( |
Baratol (explosive)
Baratol is an explosive made of a mixture of TNT and barium nitrate, with a small quantity (about 1%) of paraffin wax used as a phlegmatizing agent. TNT typically makes up 25% to 33% of the mixture. Because of the high density of barium nitrate, Baratol has a density of at least 2.5 g/cm3. Baratol, which has a detonation velocity of only about 4,900 metres per second, was used as the slow-detonating explosive in the explosive lenses of some early atomic bomb designs, with Composition B often used as the fast-detonating component. Atomic bombs detonated at Trinity in 1945, the Soviet Joe 1 in 1949, and in India in 1972 all used Baratol and Composition B. Baratol was also used in the Mills bomb "Mills bomb" is the popular name for a series of British hand grenades which were designed by William Mills. They were the first modern fragmentation grenades used by the British Army and saw widespread use in the First and Second World Wa ..., a British hand grenade. Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nagasaki
is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. It became the sole port used for trade with the Portuguese and Dutch during the 16th through 19th centuries. The Hidden Christian Sites in the Nagasaki Region have been recognized and included in the UNESCO World Heritage List. Part of Nagasaki was home to a major Imperial Japanese Navy base during the First Sino-Japanese War and Russo-Japanese War. Near the end of World War II, the American atomic bombings of Hiroshima and Nagasaki made Nagasaki the second and, to date, last city in the world to experience a nuclear attack (at 11:02 am, August 9, 1945 'Japan Standard Time (UTC+9)'). , the city has an estimated population of 407,624 and a population density of 1,004 people per km2. The total area is . History Nagasaki as a Jesuit port of call The first contact with Portuguese explorers occurred in 1543. An early visitor was Fernão Mendes Pinto, who came from Sagres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
