Portal:Nuclear technology
The Nuclear Technology Portal
Introduction
- Nuclear technology is technology that involves the nuclear reactions of atomic nuclei. Among the notable nuclear technologies are nuclear reactors, nuclear medicine and nuclear weapons. It is also used, among other things, in smoke detectors and gun sights. (Full article...)
- Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants. Nuclear decay processes are used in niche applications such as radioisotope thermoelectric generators in some space probes such as Voyager 2. Generating electricity from fusion power remains the focus of international research. (Full article...)
- 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. (Full article...)
General images -
Selected article -
Plutonium was first synthetically produced and isolated in late 1940 and early 1941, by a deuteron bombardment of uranium-238 in the 1.5-metre (60 in) cyclotron at the University of California, Berkeley. First, neptunium-238 (half-life 2.1 days) was synthesized, which subsequently beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years). Since uranium had been named after the planet Uranus and neptunium after the planet Neptune, element 94 was named after Pluto, which at the time was considered to be a planet as well. Wartime secrecy prevented the University of California team from publishing its discovery until 1948.
Plutonium is the element with the highest atomic number known to occur in nature. Trace quantities arise in natural uranium-238 deposits when uranium-238 captures neutrons emitted by decay of other uranium-238 atoms. The heavy isotope plutonium-244 has a half-life long enough that extreme trace quantities should have survived primordially (from the Earth's formation) to the present, but so far experiments have not yet been sensitive enough to detect it.
Both plutonium-239 and plutonium-241 are fissile, meaning that they can sustain a nuclear chain reaction, leading to applications in nuclear weapons and nuclear reactors. Plutonium-240 exhibits a high rate of spontaneous fission, raising the neutron flux of any sample containing it. The presence of plutonium-240 limits a plutonium sample's usability for weapons or its quality as reactor fuel, and the percentage of plutonium-240 determines its grade (weapons-grade, fuel-grade, or reactor-grade). Plutonium-238 has a half-life of 87.7 years and emits alpha particles. It is a heat source in radioisotope thermoelectric generators, which are used to power some spacecraft. Plutonium isotopes are expensive and inconvenient to separate, so particular isotopes are usually manufactured in specialized reactors.
Producing plutonium in useful quantities for the first time was a major part of the Manhattan Project during World War II that developed the first atomic bombs. The Fat Man bombs used in the Trinity nuclear test in July 1945, and in the bombing of Nagasaki in August 1945, had plutonium cores. Human radiation experiments studying plutonium were conducted without informed consent, and several criticality accidents, some lethal, occurred after the war. Disposal of plutonium waste from nuclear power plants and dismantled nuclear weapons built during the Cold War is a nuclear-proliferation and environmental concern. Other sources of plutonium in the environment are fallout from numerous above-ground nuclear tests, which are now banned. (Full article...)
Selected picture -
Did you know?
- ... that plutonium produced in the nuclear reactors at the Hanford Engineer Works was used in the Fat Man bomb used in the atomic bombing of Nagasaki in August 1945?
- ... that before becoming a successful children's author, Myron Levoy was an engineer doing research on nuclear-powered spaceships for a mission to Mars?
- ... that campaigning by climate activist Kimiko Hirata halted plans to build 17 new coal-fired power plants following the Fukushima nuclear disaster in Japan?
- ... that the Russian and Belarussian military exercise Zapad 2009 involved nuclear-capable ballistic missiles?
- ... that Helen Steven shared the Gandhi International Peace Award for her opposition to the nuclear submarine base in Scotland?
- ... that in 1958 the Scyla theta pinch device was the first to demonstrate controlled nuclear fusion in the laboratory?
Related WikiProjects
Things you can do
Parts of this portal (those related to section) need to be updated. Please help update this portal to reflect recent events or newly available information. Relevant discussion may be found on the talk page. (September 2021) |
Selected biography -
A graduate of the University of California, from which she obtained a degree in political science, Priscilla Greene started working for Lawrence in February 1942, and then for Oppenheimer later that year. She arrived in Santa Fe, New Mexico, in March 1943, and established the Los Alamos Laboratory's office. She became the office manager at Los Alamos, greeting visitors, answering the telephone, making travel arrangements, arranging security passes and accommodation, and taking notes of telephone calls. In September 1943, she married Robert B. Duffield, a chemist working at the Los Alamos laboratory, and changed her surname from Greene to Duffield.
In the post-war years, Duffield was secretary and executive assistant to Roger Revelle, the director of the Scripps Institution of Oceanography. In November 1967, she became secretary and executive assistant to Robert R. Wilson, the founding director of the National Accelerator Laboratory, and once again she helped establish a new scientific laboratory on a new site. In later life she moved to Colorado, where she served on the board of the Uncompahgre Medical Clinic. (Full article...)
Nuclear technology news
- 14 May 2024 –
- Russia places its nuclear capable submarine-launched Bulava intercontinental ballistic missile into service. (Reuters)
Related portals
Related topics
Subcategories
Associated Wikimedia
The following Wikimedia Foundation sister projects provide more on this subject:
-
Commons
Free media repository -
Wikibooks
Free textbooks and manuals -
Wikidata
Free knowledge base -
Wikinews
Free-content news -
Wikiquote
Collection of quotations -
Wikisource
Free-content library -
Wikiversity
Free learning tools -
Wiktionary
Dictionary and thesaurus