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A-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] |
Radiation Effects Research Foundation
The Radiation Effects Research Foundation (RERF) is a joint U.S.-Japan research organization responsible for studying the medical effects of radiation and associated diseases in humans for the welfare of the survivors and all humankind.Introduction to Radiation Effects Research Foundation. (1995). Radiation Effects Research Foundation, pp.1-3. Available at: http://rerf.jp/shared/introd/introRERFe.pdf ccessed 26 February 2018 The organization's scientific laboratories are located in Hiroshima and Nagasaki, Japan. RERF's studies into radiation health effects have continued for more than 70 years, making RERF unique for its conduct of epidemiological and other research on such a large population (more than 120,000 individuals) over such a long timeframe.A Brief Description. (2014). Radiation Effects Research Foundation, p.1. Available at: http://rerf.jp/shared/briefdescript/briefdescript_e.pdf ccessed 26 February 2018 RERF continues its research with the aim of further elucidating t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Bombings Of Hiroshima And Nagasaki
The United States detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki on 6 and 9 August 1945, respectively. The two bombings killed between 129,000 and 226,000 people, most of whom were civilians, and remain the only use of nuclear weapons in armed conflict so far. In the final year of World War II, the Allies prepared for a costly invasion of the Japanese mainland. This undertaking was preceded by a conventional and firebombing campaign that devastated 64 Japanese cities. The war in the European theatre concluded when Germany surrendered on 8 May 1945, and the Allies turned their full attention to the Pacific War. By July 1945, the Allies' Manhattan Project had produced two types of atomic bombs: "Fat Man", a plutonium implosion-type nuclear weapon; and "Little Boy", an enriched uranium gun-type fission weapon. The 509th Composite Group of the United States Army Air Forces was trained and equipped with the specialized Silverplate version of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hiroshima
is the capital of Hiroshima Prefecture in Japan. , the city had an estimated population of 1,199,391. The gross domestic product (GDP) in Greater Hiroshima, Hiroshima Urban Employment Area, was US$61.3 billion as of 2010. Kazumi Matsui has been the city's mayor since April 2011. Hiroshima was founded in 1589 as a castle town on the Ōta River delta. Following the Meiji Restoration in 1868, Hiroshima rapidly transformed into a major urban center and industrial hub. In 1889, Hiroshima officially gained city status. The city was a center of military activities during the imperial era, playing significant roles such as in the First Sino-Japanese War, the Russo-Japanese War, and the two world wars. Hiroshima was the first military target of a nuclear weapon in human history. This occurred on August 6, 1945, at 8:15 a.m., when the United States Army Air Forces (USAAF) dropped the atomic bomb " Little Boy" on the city. Most of Hiroshima was destroyed, and by the end o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fission 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 de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Debate Over The Atomic Bombings Of Hiroshima And Nagasaki
Substantial debate exists over the ethical, legal, and military aspects of the atomic bombings of Hiroshima and Nagasaki on 6 August and 9 August 1945 at the close of World War II (1939–45). On 26 July 1945, United States President Harry S. Truman, British Prime Minister Winston Churchill and President of China Chiang Kai-shek issued the Potsdam Declaration, which outlined the terms of surrender for the Empire of Japan as agreed upon at the Potsdam Conference. This ultimatum stated if Japan did not surrender, it would face "prompt and utter destruction". Some debaters focus on the presidential decision-making process, and others on whether or not the bombings were the proximate cause of Japanese surrender. Over the course of time, different arguments have gained and lost support as new evidence has become available and as new studies have been completed. A primary and continuing focus has been on whether the bombing should be categorized as a war crime or as a crime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TNT Equivalent
TNT equivalent is a convention for expressing energy, typically used to describe the energy released in an explosion. The is a unit of energy defined by that convention to be , which is the approximate energy released in the detonation of a metric ton (1,000 kilograms) of TNT. In other words, for each gram of TNT exploded, (or 4184 joules) of energy is released. This convention intends to compare the destructiveness of an event with that of conventional explosive materials, of which TNT is a typical example, although other conventional explosives such as dynamite contain more energy. Kiloton and megaton The "kiloton (of TNT)" is a unit of energy equal to 4.184 terajoules (). The "megaton (of TNT)" is a unit of energy equal to 4.184 petajoules (). The kiloton and megaton of TNT have traditionally been used to describe the energy output, and hence the destructive power, of a nuclear weapon. The TNT equivalent appears in various nuclear weapon control treaties, and has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes: * ''electromagnetic radiation'', such as radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma radiation (γ) * '' particle radiation'', such as alpha radiation (α), beta radiation (β), proton radiation and neutron radiation (particles of non-zero rest energy) * '' acoustic radiation'', such as ultrasound, sound, and seismic waves (dependent on a physical transmission medium) * '' gravitational radiation'', that takes the form of gravitational waves, or ripples in the curvature of spacetime Radiation is often categorized as either '' ionizing'' or ''non-ionizing'' depending on the energy of the radiated particles. Ionizing radiation carries more than 10 eV, which is enough to ionize atoms and molecules and break chemical bonds. This is an important distinction due to the large diffe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Fission
Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radioactive decay. Nuclear fission of heavy elements was discovered on Monday 19 December 1938, by German chemist Otto Hahn and his assistant Fritz Strassmann in cooperation with Austrian-Swedish physicist Lise Meitner. Hahn understood that a "burst" of the atomic nuclei had occurred. Meitner explained it theoretically in January 1939 along with her nephew Otto Robert Frisch. Frisch named the process by analogy with biological fission of living cells. For heavy nuclides, it is an exothermic reaction which can release large amounts of energy both as electromagnetic radiation and as kinetic energy of the fragments (heating the bulk material where fission takes place). Like nuclear fusion, for fission to produce energy, the total binding en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Empire Of Japan
The also known as the Japanese Empire or Imperial Japan, was a historical nation-state and great power that existed from the Meiji Restoration in 1868 until the enactment of the post-World War II 1947 constitution and subsequent formation of modern Japan. It encompassed the Japanese archipelago and several colonies, protectorates, mandates, and other territories. Under the slogans of and following the Boshin War and restoration of power to the Emperor from the Shogun, Japan underwent a period of industrialization and militarization, the Meiji Restoration, which is often regarded as the fastest modernisation of any country to date. All of these aspects contributed to Japan's emergence as a great power and the establishment of a colonial empire following the First Sino-Japanese War, the Boxer Rebellion, the Russo-Japanese War, and World War I. Economic and political turmoil in the 1920s, including the Great Depression, led to the rise of militarism, natio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fat Man
"Fat Man" (also known as Mark III) is the codename for the type of nuclear bomb the United States detonated over the Japanese city of Nagasaki on 9 August 1945. It was the second of the only two nuclear weapons ever used in warfare, the first being Little Boy, and its detonation marked the third nuclear explosion in history. It was built by scientists and engineers at Los Alamos Laboratory using plutonium from the Hanford Site, and it was dropped from the Boeing B-29 Superfortress ''Bockscar'' piloted by Major Charles Sweeney. The name Fat Man refers to the early design of the bomb because it had a wide, round shape. Fat Man was an implosion-type nuclear weapon with a solid plutonium core. The first of that type to be detonated was the Gadget in the Trinity nuclear test less than a month earlier on 16 July at the Alamogordo Bombing and Gunnery Range in New Mexico. Two more were detonated during the Operation Crossroads nuclear tests at Bikini Atoll in 1946, and some 12 ... [...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 S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Civilians
Civilians under international humanitarian law are "persons who are not members of the armed forces" and they are not " combatants if they carry arms openly and respect the laws and customs of war". It is slightly different from a non-combatant, because some non-combatants are not civilians (for example, military chaplains who are attached to the belligerent party or military personnel who are serving with a neutral country). Civilians in the territories of a party to an armed conflict are entitled to certain privileges under the customary laws of war and international treaties such as the Fourth Geneva Convention. The privileges that they enjoy under international law depends on whether the conflict is an internal one (a civil war) or an international one. In some nations, uniformed members of civilian police or fire departments colloquially refer to members of the public as civilians. Etymology The word "civilian" goes back to the late 14th century and is from Old French ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
