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]   |
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Nevada Test Site Craters
Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, the 32nd-most populous, and the 9th-least densely populated of the U.S. states. Nearly three-quarters of Nevada's people live in Clark County, which contains the Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City. Las Vegas is the largest city in the state. Nevada is officially known as the "Silver State" because of the importance of silver to its history and economy. It is also known as the "Battle Born State" because it achieved statehood during the Civil War (the words "Battle Born" also appear on its state flag); as the "Sagebrush State", for the native plant of the same name; and as the " Sage-hen State". The name means "snowy" in Spanish, refe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Concrete
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most widely used building material. Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminum combined. Globally, the ready-mix concrete industry, the largest segment of the concrete market, is projected to exceed $600 billion in revenue by 2025. This widespread use results in a number of environmental impacts. Most notably, the production process for cement produces large volumes of greenhouse gas emissions, leading to net 8% of global emissions. Other environmental concerns include widespread illegal sand mining, impacts on the surrounding environment such as increased surface runoff or urban heat island effect, and potential public health implications from toxic ingredients. Significant research and development is ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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B53 Nuclear Bomb
The Mk/B53 was a high-yield bunker buster thermonuclear weapon developed by the United States during the Cold War. Deployed on Strategic Air Command bombers, the B53, with a yield of 9 megatons, was the most powerful weapon in the U.S. nuclear arsenal after the last B41 nuclear bombs were retired in 1976. The B53 was the basis of the W-53 warhead carried by the Titan II Missile, which was decommissioned in 1987. Although not in active service for many years before 2010, fifty B53s were retained during that time as part of the "hedge" portion of the Enduring Stockpile until its complete dismantling in 2011. The last B53 was disassembled on 25 October 2011, a year ahead of schedule. With its retirement, the largest bomb currently in service in the U.S. nuclear arsenal is the B83, with a maximum yield of 1.2 megatons. The B53 was replaced in the bunker-busting role by the B61 Mod 11. History Development of the weapon began in 1955 by Los Alamos National Laboratory, base ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Isaac Newton
Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, physicist, astronomer, alchemist, theologian, and author (described in his time as a "natural philosopher"), widely recognised as one of the greatest mathematicians and physicists and among the most influential scientists of all time. He was a key figure in the philosophical revolution known as the Enlightenment. His book (''Mathematical Principles of Natural Philosophy''), first published in 1687, established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing infinitesimal calculus. In the , Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint for centuries until it was superseded by the theory of relativity. Newton used his mathematical description of gravity to derive Kepler's laws of planetary motion, account for ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Impact Depth
The impact depth of a projectile is the distance it penetrates into a target before coming to a stop. The physicist Sir Isaac Newton first developed this idea to get rough approximations for the impact depth for projectiles traveling at high velocities. Newton's approximation for the impact depth Newton's approximation for the impact depth for projectiles at high velocities is based only on momentum considerations. Nothing is said about where the impactor's kinetic energy goes, nor what happens to the momentum after the projectile is stopped. The basic idea is simple: The impactor carries a given momentum. To stop the impactor, this momentum must be transferred onto another mass. Since the impactor's velocity is so high that cohesion within the target material can be neglected, the momentum can only be transferred to the material (mass) directly in front of the impactor, which will be pushed at the impactor's speed. If the impactor has pushed a mass equal to its own mass at thi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Liquefaction
In materials science, liquefaction is a process that generates a liquid from a solid or a gas or that generates a non-liquid phase which behaves in accordance with fluid dynamics. It occurs both naturally and artificially. As an example of the latter, a "major commercial application of liquefaction is the liquefaction of air to allow separation of the constituents, such as oxygen, nitrogen, and the noble gases." Another is the conversion of solid coal into a liquid form usable as a substitute for liquid fuels. Geology In geology, soil liquefaction refers to the process by which water-saturated, unconsolidated sediments are transformed into a substance that acts like a liquid, often in an earthquake. Soil liquefaction was blamed for building collapses in the city of Palu, Indonesia in October 2018. In a related phenomenon, liquefaction of bulk materials in cargo ships may cause a dangerous shift in the load. Physics and chemistry In physics and chemistry, the phase transiti ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Eglin Air Force Base
Eglin Air Force Base is a United States Air Force (USAF) base in the western Florida Panhandle, located about southwest of Valparaiso in Okaloosa County. The host unit at Eglin is the 96th Test Wing (formerly the 96th Air Base Wing). The 96 TW is the test and evaluation center for Air Force air-delivered weapons, navigation and guidance systems, command and control systems, and Air Force Special Operations Command (AFSOC) systems. Eglin AFB was established in 1935 as the Valparaiso Bombing and Gunnery Base. It is named in honor of Lt. Col. Frederick I. Eglin who was killed in a crash of his Northrop A-17 attack aircraft on a flight from Langley to Maxwell Field, Alabama. History Creation and World War II Much of the base was part of a national forest until the outbreak of World War II in Europe when a proving ground for aircraft armament was established at Eglin. The U.S. Forest Service ceded over 340,000 acres of the Choctawhatchee National Forest to the War D ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Rocket Sled
A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely from propellant carried within the vehicle; therefore a rocket can fly in the vacuum of space. Rockets work more efficiently in a vacuum and incur a loss of thrust due to the opposing pressure of the atmosphere. Multistage rockets are capable of attaining escape velocity from Earth and therefore can achieve unlimited maximum altitude. Compared with airbreathing engines, rockets are lightweight and powerful and capable of generating large accelerations. To control their flight, rockets rely on momentum, airfoils, auxiliary reaction engines, gimballed thrust, momentum wheels, deflection of the exhaust stream, propellant flow, spin, or gravity. Rockets for military and recreational uses date back to at least 13th-century China. Significant ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Ogive
An ogive ( ) is the roundly tapered end of a two-dimensional or three-dimensional object. Ogive curves and surfaces are used in engineering, architecture and woodworking. Etymology The earliest use of the word ''ogive'' is found in the 13th century sketchbook of Villard de Honnecourt, from Picardy in northern France. The ''Oxford English Dictionary'' considers the French term's origin obscure; it might come from the Late Latin , the feminine perfect passive participle of , meaning the one who has met or encountered the other. However, Merriam-Webster's dictionary says it is from the "Middle English stone comprising an arch, from Middle French diagonal arch". Types and use in applied physical science and engineering In ballistics or aerodynamics, an ogive is a pointed, curved surface mainly used to form the approximately streamlined nose of a bullet or other projectile, reducing air resistance or the drag of air. In fact the French word ''ogive'' can be translated as "nose ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternate name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements barring carbon (which sublimes at normal pressure), melting at . It also has the highest boiling point, at . Its density is , comparable with that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work. However, pure single-crystalline tungsten is more ductile and can be cut with a hard-steel hacksaw. Tungsten occurs in many ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Secant Ogive
Secant is a term in mathematics derived from the Latin ''secare'' ("to cut"). It may refer to: * a secant line, in geometry * the secant variety, in algebraic geometry * secant (trigonometry) (Latin: secans), the multiplicative inverse (or reciprocal) trigonometric function of the cosine * the secant method, a root-finding algorithm in numerical analysis, based on secant lines to graphs of functions * a secant ogive Secant is a term in mathematics derived from the Latin ''secare'' ("to cut"). It may refer to: * a secant line, in geometry * the secant variety, in algebraic geometry * secant (trigonometry) (Latin: secans), the multiplicative inverse (or reciproc ... in nose cone design {{mathdab sr:Секанс ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Spall
Spall are fragments of a material that are broken off a larger solid body. It can be produced by a variety of mechanisms, including as a result of projectile impact, corrosion, weathering, cavitation, or excessive rolling pressure (as in a ball bearing). Spalling and spallation both describe the process of surface failure in which spall is shed. The terms ''spall'', ''spalling'', and ''spallation'' have been adopted by particle physicists; in neutron scattering instruments, neutrons are generated by bombarding a uranium (or other) target with a stream of atoms. The neutrons that are ejected from the target are known as "spall". Mechanical spalling Mechanical spalling occurs at high stress contact points, for example, in a ball bearing. Spalling occurs in preference to brinelling where the maximal shear stress occurs not at the surface, but just below, shearing the spall off. One of the simplest forms of mechanical spalling is plate impact, in which two waves of compression ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |