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Louis Slotin
Louis Alexander Slotin ( ; 1 December 1910 – 30 May 1946) was a Canadian physicist and chemist who took part in the Manhattan Project. Born and raised in the North End of Winnipeg, Manitoba, Slotin earned both his Bachelor of Science and Master of Science degrees from the University of Manitoba, before obtaining his doctorate in physical chemistry at King's College London in 1936. Afterwards, he joined the University of Chicago as a research associate to help design a cyclotron. In 1942, Slotin was invited to participate in the Manhattan Project, and subsequently performed experiments with uranium and plutonium cores to determine their critical mass values. After World War II, he continued his research at Los Alamos National Laboratory in New Mexico. On 21 May 1946, he accidentally triggered a fission reaction, which released a burst of hard radiation. He was rushed to the hospital and died nine days later on 30 May. Slotin had become the second fatal victim of a criti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winnipeg
Winnipeg () is the capital and largest city of the Provinces and territories of Canada, Canadian province of Manitoba. It is centred on the confluence of the Red River of the North, Red and Assiniboine River, Assiniboine rivers. , Winnipeg had a city population of 749,607 and a metropolitan population of 834,678, making it Canada's List of the largest municipalities in Canada by population, sixth-largest city and List of census metropolitan areas and agglomerations in Canada, eighth-largest metropolitan area. The city is named after the nearby Lake Winnipeg; the name comes from the Cree language, Western Cree words for 'muddy water' – . The region was a trading centre for Indigenous peoples in Canada, Indigenous peoples long before the European colonization of the Americas, arrival of Europeans; it is the traditional territory of the Anishinaabe (Ojibway), Ininew (Cree), Oji-Cree, Dene, and Dakota people, Dakota, and is the birthplace of the Métis people in Canada, Métis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium
Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium radioactive decay, radioactively decays, usually by emitting an alpha particle. The half-life of this decay varies between 159,200 and 4.5 billion years for different isotopes of uranium, isotopes, making them useful for dating the age of the Earth. The most common isotopes in natural uranium are uranium-238 (which has 146 neutrons and accounts for over 99% of uranium on Earth) and uranium-235 (which has 143 neutrons). Uranium has the highest atomic weight of the primordial nuclide, primordially occurring elements. Its density is about 70% higher than that of lead and slightly lower than that of gold or tungsten. It occurs naturally in low concentrations of a few Parts-per notation#Parts-per expressions, parts per million in soil, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-Jewish Pogroms In The Russian Empire
Pogroms in the Russian Empire () were large-scale, targeted, and repeated anti-Jewish riots that began in the 19th century. Pogroms began to occur after Imperial Russia, which previously had very few Jews, acquired territories with large Jewish populations from the Polish–Lithuanian Commonwealth and the Ottoman Empire from 1772 to 1815. These territories were designated "the Pale of Settlement" by the Imperial Russian government, within which Jews were reluctantly permitted to live. The Pale of Settlement primarily included the territories of Poland, Ukraine, Belarus, Bessarabia (modern Moldova), Lithuania and Crimea. Jews were forbidden from moving to other parts of European Russia (including Finland), unless they converted from Judaism or obtained a university diploma or first guild merchant status. Migration to the Caucasus, Siberia, the Far East or Central Asia was not restricted. Early pogroms Riots against Jews that took place before 1881 are sometimes retroactively class ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jews
Jews (, , ), or the Jewish people, are an ethnoreligious group and nation, originating from the Israelites of History of ancient Israel and Judah, ancient Israel and Judah. They also traditionally adhere to Judaism. Jewish ethnicity, religion, and community are highly interrelated, as Judaism is their ethnic religion, though it is not practiced by all ethnic Jews. Despite this, religious Jews regard Gerim, converts to Judaism as members of the Jewish nation, pursuant to the Conversion to Judaism, long-standing conversion process. The Israelites emerged from the pre-existing Canaanite peoples to establish Kingdom of Israel (Samaria), Israel and Kingdom of Judah, Judah in the Southern Levant during the Iron Age.John Day (Old Testament scholar), John Day (2005), ''In Search of Pre-Exilic Israel'', Bloomsbury Publishing, pp. 47.5 [48] 'In this sense, the emergence of ancient Israel is viewed not as the cause of the demise of Canaanite culture but as its upshot'. Originally, J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yiddish
Yiddish, historically Judeo-German, is a West Germanic language historically spoken by Ashkenazi Jews. It originated in 9th-century Central Europe, and provided the nascent Ashkenazi community with a vernacular based on High German fused with many elements taken from Hebrew language, Hebrew (notably Mishnaic Hebrew, Mishnaic) and to some extent Aramaic. Most varieties of Yiddish include elements of Slavic languages and the vocabulary contains traces of Romance languages.Aram Yardumian"A Tale of Two Hypotheses: Genetics and the Ethnogenesis of Ashkenazi Jewry".University of Pennsylvania. 2013. Yiddish has traditionally been written using the Hebrew alphabet. Prior to World War II, there were 11–13 million speakers. 85% of the approximately 6 million Jews who were murdered in the Holocaust were Yiddish speakers,Solomon Birnbaum, ''Grammatik der jiddischen Sprache'' (4., erg. Aufl., Hamburg: Buske, 1984), p. 3. leading to a massive decline in the use of the language. Jewish ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Demon Core
The demon core was a sphere of plutonium that was involved in two fatal radiation accidents when scientists tested it as a fissile core of an early atomic bomb. It was manufactured in 1945 by the Manhattan Project, the U.S. nuclear weapon development effort during World War II. It was a subcritical mass that weighed and was in diameter. The core was prepared for shipment to the Pacific Theater as part of the third nuclear weapon to be dropped on Japan, but when Japan surrendered, the core was retained for testing and potential later use in the case of another conflict. The two criticality accidents occurred at the Los Alamos Laboratory in New Mexico on August 21, 1945, and May 21, 1946. In both cases, an experiment was intended to demonstrate how close the core was to criticality, using a neutron-reflective tamper (layer of dense material surrounding the fissile material). In both accidents, the core was accidentally put into a critical configuration. Physicists Harry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harry Daghlian
Haroutune Krikor Daghlian Jr. (May 4, 1921 – September 15, 1945) was an American physicist with the Manhattan Project, which designed and produced the atomic bombs that were used in World War II. He accidentally irradiated himself on August 21, 1945, during a critical mass experiment at the remote Omega Site of the Los Alamos Laboratory in New Mexico and died 25 days later from the resultant radiation poisoning. Daghlian was irradiated as a result of a criticality accident that occurred when he accidentally dropped a tungsten carbide brick onto a 6.2 kg bomb core made of plutonium–gallium alloy. This core, subsequently nicknamed the " demon core", was later involved in the death of another physicist, Louis Slotin. Early life and education Haroutune Krikor Daghlian Jr., was born in Waterbury, Connecticut, on May 4, 1921, one of three children of Margaret Rose (''née'' Currie) and Haroutune Krikor Daghlian. His father was an ethnic Armenian from Gaziantep in wha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Criticality Accident
A criticality accident is an accidental uncontrolled nuclear fission chain reaction. It is sometimes referred to as a critical excursion, critical power excursion, divergent chain reaction, or simply critical. Any such event involves the unintended accumulation or arrangement of a critical mass of fissile material, for example enriched uranium or plutonium. Criticality accidents can release potentially fatal radiation doses if they occur in an unprotected environment. Under normal circumstances, a critical or supercritical fission reaction (one that is self-sustaining in power or increasing in power) should only occur inside a safely shielded location, such as a reactor core or a suitable test environment. A criticality accident occurs if the same reaction is achieved unintentionally, for example in an unsafe environment or during reactor maintenance. Though dangerous and frequently lethal to humans within the immediate area, the critical mass formed would not be capable of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hard Radiation
Ionizing (ionising) radiation, including nuclear radiation, consists of subatomic particles or electromagnetic waves that have enough energy per individual photon or particle to ionize atoms or molecules by detaching electrons from them. Some particles can travel up to 99% of the speed of light, and the electromagnetic waves are on the high-energy portion of the electromagnetic spectrum. Gamma rays, X-rays, and the higher energy ultraviolet part of the electromagnetic spectrum are ionizing radiation; whereas the lower energy ultraviolet, visible light, infrared, microwaves, and radio waves are non-ionizing radiation. Nearly all types of laser light are non-ionizing radiation. The boundary between ionizing and non-ionizing radiation in the ultraviolet area cannot be sharply defined, as different molecules and atoms ionize at different energies. The energy of ionizing radiation starts between 10 electronvolts (eV) and 33 eV. Ionizing subatomic particles include alpha par ... [...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 was discovered by chemists Otto Hahn and Fritz Strassmann and physicists Lise Meitner and Otto Robert Frisch. Hahn and Strassmann proved that a fission reaction had taken place on 19 December 1938, and Meitner and her nephew Frisch explained it theoretically in January 1939. Frisch named the process "fission" by analogy with biological fission of living cells. In their second publication on nuclear fission in February 1939, Hahn and Strassmann predicted the existence and liberation of additional neutrons during the fission process, opening up the possibility of a nuclear chain reaction. For heavy nuclides, it is an exothermic reaction which can release large amounts of energy both as electromagnetic radiat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Mexico
New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also borders the state of Texas to the east and southeast, Oklahoma to the northeast, and shares Mexico-United States border, an international border with the Mexican states of Chihuahua (state), Chihuahua and Sonora to the south. New Mexico's largest city is Albuquerque, and its List of capitals in the United States, state capital is Santa Fe, New Mexico, Santa Fe, the oldest state capital in the U.S., founded in 1610 as the government seat of Santa Fe de Nuevo México, Nuevo México in New Spain. It also has the highest elevation of any state capital, at . New Mexico is the List of U.S. states and territories by area, fifth-largest of the fifty states by area, but with just over 2.1 million residents, ranks List of U.S. states and terri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
