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Chernobyl Nuclear Disaster
The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the No. 4 reactor in the Chernobyl Nuclear Power Plant, near the city of Pripyat in the north of the Ukrainian SSR in the Soviet Union. It is one of only two nuclear energy accidents rated at seven—the maximum severity—on the International Nuclear Event Scale, the other being the 2011 Fukushima nuclear disaster in Japan. The initial emergency response, together with later decontamination of the environment, involved more than 500,000 personnel and cost an estimated 18 billion roubles—roughly US$68 billion in 2019, adjusted for inflation. The accident occurred during a safety test meant to measure the ability of the steam turbine to power the emergency feedwater pumps of an RBMK-type nuclear reactor in the event of a simultaneous loss of external power and major coolant leak. During a planned decrease of reactor power in preparation for the test, the operators accidentally drop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moscow Summer Time
Moscow Time (MSK, russian: моско́вское вре́мя) is the time zone for the city of Moscow, Russia, and most of western Russia, including Saint Petersburg. It is the second-westernmost of the eleven time zones of Russia. It has been set to UTC+03:00 without DST since 26 October 2014; before that date it had been set to UTC+04:00 year-round on 27 March 2011. Moscow Time is used to schedule trains, ships, etc. throughout Russia, but airplane travel is scheduled using local time. Times in Russia are often announced throughout the country on radio stations as Moscow Time, which is also registered in telegrams, etc. Descriptions of time zones in Russia are often based on Moscow Time rather than UTC. For example, Yakutsk ( UTC+09:00) is said to be MSK+6 in Russia. History Until the October Revolution, the official time in Moscow corresponded to GMT+02:30:17 (according to the longitude of the Astronomical Observatory of Moscow State University). In 1919 the Coun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chernobyl Liquidators
Chernobyl liquidators were the civil and military personnel who were called upon to deal with the consequences of the 1986 Chernobyl nuclear disaster in the Soviet Union on the site of the event. The liquidators are widely credited with limiting both the immediate and long-term damage from the disaster. Surviving liquidators are qualified for significant social benefits due to their veteran status. Many liquidators were praised as heroes by the Soviet Government and the press, while some struggled for years to have their participation officially recognized. Name The colloquial term "liquidator" ( ua, ліквідатор, be, ліквідатар, russian: ликвида́тор, ''likvidator'') originates from the Soviet official definition "участник ликвидации последствий аварии на Чернобыльской АЭС" (''uchastnik likvidatsii'' ''posledstviy avarii na Chernobylʹskoy AES'', literally "participant in liquidation of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear No-threshold
The linear no-threshold model (LNT) is a dose-response model used in radiation protection to estimate stochastic health effects such as radiation-induced cancer, genetic mutations and teratogenic effects on the human body due to exposure to ionizing radiation. The model statistically extrapolates effects of radiation from very high doses (where they are observable) into very low doses, where no biological effects may be observed. The LNT model lies at a foundation of a postulate that all exposure to ionizing radiation is harmful, regardless of how low the dose is, and that the effect is cumulative over lifetime. The LNT model is commonly used by regulatory bodies as a basis for formulating public health policies that set regulatory dose limits to protect against the effects of radiation. The model has also been used in the assessment of cancer risks of mutagenic chemicals. The validity of the LNT model, however, is disputed, and other significant models exist: the threshold m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United Nations Scientific Committee On The Effects Of Atomic Radiation
The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was set up by resolution of the United Nations General Assembly in 1955. 21 states are designated to provide scientists to serve as members of the committee which holds formal meetings (sessions) annually and submits a report to the General Assembly. The organisation has no power to set radiation standards nor to make recommendations in regard to nuclear testing. It was established solely to "define precisely the present exposure of the population of the world to ionizing radiation." A small secretariat, located in Vienna and functionally linked to the UN Environment Program, organizes the annual sessions and manages the preparation of documents for the committee's scrutiny. Function UNSCEAR issues major public reports on ''Sources and Effects of Ionizing Radiation'' from time to time. As of 2017, there have been 28 major publications from 1958 to 2017. The reports are all available from the UN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid Cancer
Thyroid cancer is cancer that develops from the tissues of the thyroid gland. It is a disease in which cells grow abnormally and have the potential to spread to other parts of the body. Symptoms can include swelling or a lump in the neck. Cancer can also occur in the thyroid after spread from other locations, in which case it is not classified as thyroid cancer. Risk factors include radiation exposure at a young age, having an enlarged thyroid, and family history. The four main types are papillary thyroid cancer, follicular thyroid cancer, medullary thyroid cancer, and anaplastic thyroid cancer. Diagnosis is often based on ultrasound and fine needle aspiration. Screening people without symptoms and at normal risk for the disease is not recommended as of 2017. Treatment options may include surgery, radiation therapy including radioactive iodine, chemotherapy, thyroid hormone, targeted therapy, and watchful waiting. Surgery may involve removing part or all of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chernobyl Exclusion Zone
The Chernobyl Nuclear Power Plant Zone of Alienation, Belarusian: Хона адчужэння Чарнобыльскай АЭС, ''Zona adčužennia Čarnobyĺskaj AES'', russian: Зона отчуждения Чернобыльской АЭС, translit=Zona otchuzhdeniya Chernobyl'skoy AES is an officially designated exclusion zone around the site of the Chernobyl nuclear reactor disaster. It is also commonly known as the Chernobyl Exclusion Zone, the 30-Kilometre Zone, or The Zone., Belarusian: Чарнобыльская зона, romanized: ''Charnobyl'skaya zona'', russian: Чернобыльская зона, translit=Chernobyl'skaya zona). Established by the Soviet Armed Forces soon after the 1986 disaster, it initially existed as an area of radius from the Chernobyl Nuclear Power Plant designated for evacuation and placed under military control. Its borders have since been altered to cover a larger area of Ukraine. The Chernobyl Exclusion Zone borders a separately ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belarusian Soviet Socialist Republic
The Byelorussian Soviet Socialist Republic (BSSR, or Byelorussian SSR; be, Беларуская Савецкая Сацыялістычная Рэспубліка, Bielaruskaja Savieckaja Sacyjalistyčnaja Respublika; russian: Белорусская Советская Социалистическая Республика, Byelorusskaya Sovyetskaya Sotsialisticheskaya Respublika or russian: links=no, Белорусская ССР, Belorusskaya SSR), also commonly referred to in English as Byelorussia, was a republic of the Soviet Union (USSR). It existed between 1920 and 1922, and from 1922 to 1991 as one of fifteen constituent republics of the USSR, with its own legislation from 1990 to 1991. The republic was ruled by the Communist Party of Byelorussia and was also referred to as Soviet Byelorussia or Soviet Belarus by a number of historians. Other names for Byelorussia included White Russian Soviet Socialist Republic and Belorussian Soviet Socialist Republic. To the wes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioactive Contamination
Radioactive contamination, also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is unintended or undesirable (from the International Atomic Energy Agency (IAEA) definition). Such contamination presents a hazard because the radioactive decay of the contaminants, produces ionizing radiation (namely alpha, beta, gamma rays and free neutrons). The degree of hazard is determined by the concentration of the contaminants, the energy of the radiation being emitted, the type of radiation, and the proximity of the contamination to organs of the body. It is important to be clear that the contamination gives rise to the radiation hazard, and the terms "radiation" and "contamination" are not interchangeable. The sources of radioactive pollution can be classified into two groups: natural and man-made. Following an atmospheric nuclear weapon discharge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Meltdown
A nuclear meltdown (core meltdown, core melt accident, meltdown or partial core melt) is a severe nuclear reactor accident that results in core damage from overheating. The term ''nuclear meltdown'' is not officially defined by the International Atomic Energy Agency or by the United States Nuclear Regulatory Commission. It has been defined to mean the accidental melting of the core of a nuclear reactor, however, and is in common usage a reference to the core's either complete or partial collapse. A core meltdown accident occurs when the heat generated by a nuclear reactor exceeds the heat removed by the cooling systems to the point where at least one nuclear fuel element exceeds its melting point. This differs from a fuel element failure, which is not caused by high temperatures. A meltdown may be caused by a loss of coolant, loss of coolant pressure, or low coolant flow rate or be the result of a criticality excursion in which the reactor is operated at a power level t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corium (nuclear Reactor)
The Three Mile Island reactor 2 after the partial meltdown. Corium, also called fuel-containing material (FCM) or lava-like fuel-containing material (LFCM), is a material that is created in a nuclear reactor core during a nuclear meltdown accident. Resembling lava in consistency, it consists of a mixture of nuclear fuel, fission products, control rods, structural materials from the affected parts of the reactor, products of their chemical reaction with air, water and steam, and, in the event that the reactor vessel is breached, molten concrete from the floor of the reactor room. Composition and formation The heat causing the melting of a reactor may originate from the nuclear chain reaction, but more commonly decay heat of the fission products contained in the fuel rods is the primary heat source. The heat production from radioactive decay drops quickly, as the short half-life isotopes provide most of the heat and radioactive decay, with the curve of decay heat bei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scram
A scram or SCRAM is an emergency shutdown of a nuclear reactor effected by immediately terminating the fission reaction. It is also the name that is given to the manually operated kill switch that initiates the shutdown. In commercial reactor operations, this type of shutdown is often referred to as a "scram" at boiling water reactors (BWR), a "reactor ''trip''" at pressurized water reactors and at a CANDU reactor. In many cases, a scram is part of the routine shutdown procedure, which serves to test the emergency shutdown system. The etymology of the term is a matter of debate. United States Nuclear Regulatory Commission historian Tom Wellock notes that '' scram'' is English-language slang for leaving quickly and urgently, and cites this as the original and most likely accurate basis for the use of ''scram'' in the technical context. A persistent alternative explanation posits that ''scram'' is an acronym for "safety control rod axe man", which was supposedly coined by En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
