Thorium. A radioactive element of the actinide series of metals. It has an atomic symbol Th, atomic number 90, and atomic weight 232.04. It is used as fuel in nuclear reactors to produce fissionable uranium isotopes. Because of its radioopacity, various thorium compounds are used to facilitate visualization in roentgenography.
Thorium oxide (ThO2). A radiographic contrast agent that was used in the early 1930s through about 1954. High rates of mortality have been linked to its use and it has been shown to cause liver cancer.
Inorganic compounds that contain thorium as an integral part of the molecule.
Uranium. A radioactive element of the actinide series of metals. It has an atomic symbol U, atomic number 92, and atomic weight 238.03. U-235 is used as the fissionable fuel in nuclear weapons and as fuel in nuclear power reactors.
A genus of GREEN ALGAE in the family Scenedesmaceae. It forms colonies of usually four or eight cylindrical cells that are widely distributed in freshwater and SOIL.
Pollutants, present in soil, which exhibit radioactivity.
A series of radioactive elements from ACTINIUM, atomic number 89, to and including LAWRENCIUM, atomic number 103.
Pollutants, present in water or bodies of water, which exhibit radioactivity.
An antiseptic with mild fungistatic, bacteriostatic, anthelmintic, and amebicidal action. It is also used as a reagent and metal chelator, as a carrier for radio-indium for diagnostic purposes, and its halogenated derivatives are used in addition as topical anti-infective agents and oral antiamebics.
A non-taxonomic term for unicellular microscopic algae which are found in both freshwater and marine environments. Some authors consider DIATOMS; CYANOBACTERIA; HAPTOPHYTA; and DINOFLAGELLATES as part of microalgae, even though they are not algae.
Americium. A completely man-made radioactive actinide with atomic symbol Am, atomic number 95, and atomic weight 243. Its valence can range from +3 to +6. Because of its nonmagnetic ground state, it is an excellent superconductor. It is also used in bone mineral analysis and as a radiation source for radiotherapy.
Pollutants, present in air, which exhibit radioactivity.
Radiation from sources other than the source of interest. It is due to cosmic rays and natural radioactivity in the environment.
Protactinium. A radioactive element of the actinide group of metals. It has the atomic symbol Pa, atomic number 91, and atomic weight 231. It decays by alpha-emission.
Plutonium. A naturally radioactive element of the actinide metals series. It has the atomic symbol Pu, atomic number 94, and atomic weight 242. Plutonium is used as a nuclear fuel, to produce radioisotopes for research, in radionuclide batteries for pacemakers, and as the agent of fission in nuclear weapons.
An element of the rare earth family of metals. It has the atomic symbol Ce, atomic number 58, and atomic weight 140.12. Cerium is a malleable metal used in industrial applications.
Actinium. A trivalent radioactive element and the prototypical member of the actinide family. It has the atomic symbol Ac, atomic number 89, and atomic weight 227.0278. Its principal isotope is 227 and decays primarily by beta-emission.
Discarded animal and vegetable matter from a kitchen or the refuse from food preparation. (From Random House College Dictionary, 1982)
A combustible, gaseous mixture of low-molecular weight PARAFFIN hydrocarbons, generated below the surface of the earth. It contains mostly METHANE and ETHANE with small amounts of PROPANE; BUTANES; and higher hydrocarbons, and sometimes NITROGEN; CARBON DIOXIDE; HYDROGEN SULFIDE; and HELIUM. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Facilities that convert NUCLEAR ENERGY into electrical energy.
Nuclear power accident that occurred following the Tohoku-Kanto earthquake of March 11, 2011 in the northern region of Japan.
Any combustible hydrocarbon deposit formed from the remains of prehistoric organisms. Examples are petroleum, coal, and natural gas.
Energy released by nuclear fission or nuclear fusion.
Liquid, solid, or gaseous waste resulting from mining of radioactive ore, production of reactor fuel materials, reactor operation, processing of irradiated reactor fuels, and related operations, and from use of radioactive materials in research, industry, and medicine. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Nuclear reaction in which the nucleus of a heavy atom such as uranium or plutonium is split into two approximately equal parts by a neutron, charged particle, or photon.
Contractual arrangement between the lessor (owner) and the lessee in which the use of equipment or facilities is granted to the lessee for a period of time and at a specified rate.
A body of stories, the origins of which may be unknown or forgotten, that serve to explain practices, beliefs, institutions or natural phenomena. Mythology includes legends and folk tales. It may refer to classical mythology or to a body of modern thought and modern life. (From Webster's 1st ed)
The seventh planet in order from the sun. It is one of the five outer planets of the solar system. It has five known natural satellites.
Unstable isotopes of cesium that decay or disintegrate emitting radiation. Cs atoms with atomic weights of 123, 125-132, and 134-145 are radioactive cesium isotopes.
The use of wings or wing-like appendages to remain aloft and move through the air.
A group of painful oral symptoms associated with a burning or similar sensation. There is usually a significant organic component with a degree of functional overlay; it is not limited to the psychophysiologic group of disorders.
The vessels carrying blood away from the capillary beds.
Use of sophisticated analysis tools to sort through, organize, examine, and combine large sets of information.
The process of producing a form or impression made of metal or plaster using a mold.
A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions.
A weight-carrying structure for navigation of the air that is supported either by its own buoyancy or by the dynamic action of the air against its surfaces. (Webster, 1973)
Alloys that contain a high percentage of gold. They are used in restorative or prosthetic dentistry.
Native, inorganic or fossilized organic substances having a definite chemical composition and formed by inorganic reactions. They may occur as individual crystals or may be disseminated in some other mineral or rock. (Grant & Hackh's Chemical Dictionary, 5th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A family of winged insects of the suborder HETEROPTERA, called assassin bugs, because most prey on other insects. However one subfamily, TRIATOMINAE, attacks humans and other vertebrates and transmits Chagas disease.
The organization and operation of the business aspects of a physician's practice.
Global conflict primarily fought on European continent, that occurred between 1914 and 1918.
Hostile conflict between organized groups of people.