|
Mache (unit)
Mache (symbol ME from German Mache-Einheit, plural Maches) is a unit of volumic radioactivity named for the Austrian physicist Heinrich Mache. It was defined as the quantity of radon (ignoring its daughter isotope In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps (de ...s; in practice, mostly radon-222) per litre of air which ionises a sustained current of 0.001 esu (0.001 StatAmpere). 1 ME = 3.64 Eman = 3.64×10−10 Ci/L = 13.4545 Bq/L. References Units of radioactivity Obsolete units of measurement {{measurement-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heinrich Mache
Heinrich Mache (27 April 1876 – 1 September 1954) was an Austrian physicist. He won the Haitinger Prize of the Austrian Academy of Sciences in 1915. Life Born in Prague, after his secondary school studies, Mache completed the first year of physics in Prague, among other things, heard lectures by Ernst Mach and in 1894 moved with his family to Vienna, where he continued his studies with Franz Serafin Exner and continued with Ludwig Boltzmann. He received his doctorate in 1898 working under Exner on the "experimental proof of electrostriction in gases" and worked as a photographic expert during 1900/1901 and participated in the astronomical expedition for the Vienna Academy to India. In connection with his research he conducted air electrical measurements on the Red Sea, in Delhi, Ceylon and Upper Egypt. In 1901 he habilitated at the University of Vienna. In 1906 he was appointed associate professor at the University of Innsbruck, which he left after two years in order ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radon
Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colourless, odourless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through which thorium and uranium slowly decay into various short-lived radioactive elements and lead. Radon itself is the immediate decay product of radium. Its most stable isotope, 222Rn, has a half-life of only 3.8 days, making it one of the rarest elements. Since thorium and uranium are two of the most common radioactive elements on Earth, while also having three isotopes with half-lives on the order of several billion years, radon will be present on Earth long into the future despite its short half-life. The decay of radon produces many other short-lived nuclides, known as "radon daughters", ending at stable isotopes of lead. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daughter Isotope
In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps (decay chain). For example, 238U decays to 234Th which decays to 234mPa which decays, and so on, to 206Pb (which is stable): : \ce \overbrace^\ce left, upThe decay chain from lead-212 down to lead-208, showing the intermediate decay products In this example: * 234Th, 234mPa,...,206Pb are the decay products of 238U. * 234Th is the daughter of the parent 238U. * 234mPa (234 metastable) is the granddaughter of 238U. These might also be referred to as the daughter products of 238U. (''Depleted Uranium'' — authors: Naomi H. Harley, Ernest C. Foulkes, Lee H. Hil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionises
Ionization, or Ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecule is called an ion. Ionization can result from the loss of an electron after collisions with subatomic particles, collisions with other atoms, molecules and ions, or through the interaction with electromagnetic radiation. Heterolytic bond cleavage and heterolytic substitution reactions can result in the formation of ion pairs. Ionization can occur through radioactive decay by the internal conversion process, in which an excited nucleus transfers its energy to one of the inner-shell electrons causing it to be ejected. Uses Everyday examples of gas ionization are such as within a fluorescent lamp or other electrical discharge lamps. It is also used in radiation detectors such as the Geiger-Müller counter or the ionization chamber. The ionizati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrostatic Units
The electrostatic system of units (CGS-ESU) is a system of units used to measure quantities of electric charge, electric current, and voltage within the centimetre–gram–second (or "CGS") system of metric units. In electrostatic units, electrical charge is defined by the force that it exerts on other charges. Although CGS units have mostly been replaced by the '' International System of Units'', electrostatic units are still in occasional use in some applications, most notably in certain types of physics such as in particle physics and astrophysics. The main electrostatic units are: *The statcoulomb, called the franklin or the "esu" for electric charge *The statvolt for voltage *The statampere for electric current. The CGS-ESU units for magnetic quantities are seldom used, and don't have special names. Sources tend to just use 'esu' or the derived unit expressed in terms of the CGS base units. For example, the unit for magnetic induction is g/cm, corresponding to ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
StatAmpere
The statampere (statA) is the derived electromagnetic unit of electric current in the CGS-ESU (electrostatic cgs) and Gaussian systems of units. One statampere corresponds to / ampere ≈ in the SI system of units. The name ''statampere'' is a shortening of ''abstatampere'', where the idea was that the prefix ''abstat'' should stand for ''absolute electrostatic'' and mean ‘belonging to the CGS-ESU (electrostatic cgs) absolute system of units’. The esu-cgs (or "electrostatic cgs") units are one of several systems of electromagnetic units within the centimetre–gram–second system of units; others include CGS-EMU (or "electrostatic cgs units"), Gaussian units, and Heaviside–Lorentz units. In the cgs-emu system, the unit of electric current is the abampere. The unit of current in the Heaviside–Lorentz system doesn't have a special name. The other units in the cgs-esu and Gaussian systems related to the statampere are: * statcoulomb – the charge that passes in one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curie (unit)
The curie (symbol Ci) is a non- SI unit of radioactivity originally defined in 1910. According to a notice in ''Nature'' at the time, it was to be named in honour of Pierre Curie, but was considered at least by some to be in honour of Marie Curie as well, and is in later literature considered to be named for both. It was originally defined as "the quantity or mass of radium emanation in equilibrium with one gram of radium (element)", but is currently defined as 1 Ci = decays per second after more accurate measurements of the activity of 226Ra (which has a specific activity of ). In 1975 the General Conference on Weights and Measures gave the becquerel (Bq), defined as one nuclear decay per second, official status as the SI unit of activity. Therefore: : 1 Ci = = 37 GBq and : 1 Bq ≅ ≅ 27 pCi While its continued use is discouraged by National Institute of Standards and Technology (NIST) and other bodies, the curie is still widely used throughou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Becquerel
The becquerel (; symbol: Bq) is the unit of radioactivity in the International System of Units (SI). One becquerel is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. For applications relating to human health this is a small quantity, and SI multiples of the unit are commonly used. The becquerel is named after Henri Becquerel, who shared a Nobel Prize in Physics with Pierre and Marie Skłodowska Curie in 1903 for their work in discovering radioactivity. Definition 1 Bq = 1 s−1 A special name was introduced for the reciprocal second (s−1) to represent radioactivity to avoid potentially dangerous mistakes with prefixes. For example, 1 µs−1 would mean 106 disintegrations per second: 1·(10−6 s)−1 = 106 s−1, whereas 1 µBq would mean 1 disintegration per 1 million seconds. Other names considered were hertz (Hz), a special name already in use for the reciprocal second, and Fourier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Units Of Radioactivity
Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (album), 1997 album by the Australian band Regurgitator * The Units, a synthpunk band Television * ''The Unit'', an American television series * '' The Unit: Idol Rebooting Project'', South Korean reality TV survival show Business * Stock keeping unit, a discrete inventory management construct * Strategic business unit, a profit center which focuses on product offering and market segment * Unit of account, a monetary unit of measurement * Unit coin, a small coin or medallion (usually military), bearing an organization's insignia or emblem * Work unit, the name given to a place of employment in the People's Republic of China Science and technology Science and medicine * Unit, a vessel or section of a chemical plant * Blood unit, a measurement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
