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Paul Villard
Paul Ulrich Villard (28 September 1860 – 13 January 1934) was a French chemist and physicist. He discovered gamma rays in 1900 while studying the radiation emanating from radium. Early research Villard was born in Saint-Germain-au-Mont-d'Or, Rhône. He graduated from the École Normale Supérieure in 1881 and taught in several Lycées, ending with a Lycée in Montpellier. He would maintain a laboratory position at the Ecole Normale Supérieure until his retirement. At the time when he discovered what we now call gamma rays, Villard was working in the chemistry department of the École Normale Supérieure rue d'Ulm, Paris. Villard is also credited with the discovery of argon hydrate. He spent the early part of his career (1888–1896) focusing on similar compounds at high pressure. Discovery of gamma rays Villard investigated the radiation emitted by radium salts via a narrow aperture in a shielded container onto a photographic plate, through a thin layer of lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saint-Germain-au-Mont-d'Or
Saint-Germain-au-Mont-d'Or () is a commune in the Metropolis of Lyon in Auvergne-Rhône-Alpes region in eastern France. Geography It lies 12 km (7.4 mi) north of Lyon on the right bank of the Saône river. Population Sights * The medieval castle A castle is a type of fortification, fortified structure built during the Middle Ages predominantly by the nobility or royalty and by Military order (monastic society), military orders. Scholars usually consider a ''castle'' to be the private .... References External links Official site Communes of Lyon Metropolis Lyonnais {{Lyon-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Ray
A gamma ray, also known as gamma radiation (symbol ), is a penetrating form of electromagnetic radiation arising from high energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. It consists of the shortest wavelength electromagnetic waves, typically shorter than those of X-rays. With frequencies above 30 exahertz () and wavelengths less than 10 picometers (), gamma ray photons have the highest photon energy of any form of electromagnetic radiation. Paul Villard, a French chemist and physicist, discovered gamma radiation in 1900 while studying radiation emitted by radium. In 1903, Ernest Rutherford named this radiation ''gamma rays'' based on their relatively strong penetration of matter; in 1900, he had already named two less penetrating types of decay radiation (discovered by Henri Becquerel) alpha rays and beta rays in ascending order of penetrating power. Gamma rays from radioactive decay are in the energy range ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Members Of The French Academy Of Sciences
Member may refer to: * Military jury, referred to as "Members" in military jargon * Element (mathematics), an object that belongs to a mathematical set * In object-oriented programming, a member of a class ** Field (computer science) In data hierarchy, a field (data field) is a Variable (computer science), variable in a record (computer science), record. A record, also known as a data structure, allows logically related data to be identified by a single name. Identifying relate ..., entries in a database ** Member variable, a variable that is associated with a specific object * Limb (anatomy), an appendage of the human or animal body ** Euphemism for penis * Structural component of a truss, connected by nodes * User (computing), a person making use of a computing service, especially on the Internet * Member (geology), a component of a geological formation * Member of parliament * The Members, a British punk rock band * Meronymy, a semantic relationship in linguistics * C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
19th-century French Physicists
The 19th century began on 1 January 1801 (represented by the Roman numerals MDCCCI), and ended on 31 December 1900 (MCM). It was the 9th century of the 2nd millennium. It was characterized by vast social upheaval. Slavery was Abolitionism, abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanded beyond its British homeland for the first time during the 19th century, particularly remaking the economies and societies of the Low Countries, France, the Rhineland, Northern Italy, and the Northeastern United States. A few decades later, the Second Industrial Revolution led to ever more massive urbanization and much higher levels of productivity, profit, and prosperity, a pattern that continued into the 20th century. The Catholic Church, in response to the growing influence and power of modernism, secularism and materialism, formed the First Vatican Council in the late 19th century to deal with such problems an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
People From Lyon Metropolis
The term "the people" refers to the public or common mass of people of a polity. As such it is a concept of human rights law, international law as well as constitutional law, particularly used for claims of popular sovereignty. In contrast, a people is any plurality of persons considered as a whole. Used in politics and law, the term "a people" refers to the collective or community of an ethnic group or nation. Concepts Legal Chapter One, Article One of the Charter of the United Nations states that "peoples" have the right to self-determination. Though the mere status as peoples and the right to self-determination, as for example in the case of Indigenous peoples (''peoples'', as in all groups of indigenous people, not merely all indigenous persons as in ''indigenous people''), does not automatically provide for independent sovereignty and therefore secession. Indeed, judge Ivor Jennings identified the inherent problems in the right of "peoples" to self-determination, as i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1934 Deaths
Events January–February * January 1 – The International Telecommunication Union, a specialist agency of the League of Nations, is established. * January 15 – The 8.0 1934 Nepal–Bihar earthquake, Nepal–Bihar earthquake strikes Nepal and Bihar with a maximum Mercalli intensity scale, Mercalli intensity of XI (''Extreme''), killing an estimated 6,000–10,700 people. * February 6 – 6 February 1934 crisis, French political crisis: The French far-right leagues rally in front of the Palais Bourbon, in an attempted coup d'état against the French Third Republic, Third Republic. * February 9 ** Gaston Doumergue forms a new government in France. ** Second Hellenic Republic, Greece, Kingdom of Romania, Romania, Turkey and Kingdom of Yugoslavia, Yugoslavia form the Balkan Pact. * February 12–February 15, 15 – Austrian Civil War: The Fatherland Front (Austria), Fatherland Front consolidates its power in a series of clashes across the country. * February 16 – The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1860 Births
Events January * January 2 – The astronomer Urbain Le Verrier announces the discovery of a hypothetical planet Vulcan (hypothetical planet), Vulcan at a meeting of the French Academy of Sciences in Paris, France. * January 10 – The Pemberton Mill in Lawrence, Massachusetts collapses, killing at least 77 workers. * January 13 – Battle of Tétouan, Morocco: Spanish troops under General Leopoldo O'Donnell, 1st Duke of Tetuan defeat the Moroccan Army. * January 20 – Camillo Benso, Count of Cavour is recalled as Prime Minister of Piedmont-Sardinia. February * February 20 – Canadian Royal Mail steamer (1859) is wrecked on Cape Sable Island, Nova Scotia, on passage from the British Isles to the United States with all 205 onboard lost. * February 26 – The 1860 Wiyot Massacre, Wiyot Massacre takes place at Tuluwat Island, Humboldt Bay in northern California. * February 26, February 27 – Abraham Lincoln makes his Cooper Union speech, Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roentgen (unit)
The roentgen or röntgen (; symbol R) is a legacy unit of measurement for the exposure of X-rays and gamma rays, and is defined as the electric charge freed by such radiation in a specified volume of air divided by the mass of that air (statcoulomb per kilogram). In 1928, it was adopted as the first international measurement quantity for ionizing radiation to be defined for radiation protection, as it was then the most easily replicated method of measuring air ionization by using ion chambers. It is named after the German physicist Wilhelm Röntgen, who discovered X-rays and was awarded the first Nobel Prize in Physics for the discovery. However, although this was a major step forward in standardising radiation measurement, the roentgen has the disadvantage that it is only a measure of air ionisation, and not a direct measure of radiation absorption in other materials, such as different forms of human tissue. For instance, one roentgen deposits of absorbed dose in dry air, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerma (physics)
In radiation physics, kerma is an acronym for "kinetic energy released per unit mass" (alternately, "kinetic energy released in matter", "kinetic energy released in material", or "kinetic energy released in materials"), defined as the sum of the initial kinetic energies of all the charged particles liberated by uncharged ionizing radiation (i.e., indirectly ionizing radiation such as photons and neutrons) in a sample of matter, divided by the mass of the sample. It is defined by the quotient K = \operatorname\!E_\text/\operatorname\!m. Units The SI unit of kerma is the gray (Gy) (or joule per kilogram), the same as the unit of absorbed dose. However, kerma can be different from absorbed dose, depending on the energies involved. This is because ionization energy is not accounted for. While kerma approximately equals absorbed dose at low energies, kerma is much higher than absorbed dose at higher energies, because some energy escapes from the absorbing volume in the form of brem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionization
Ionization or ionisation is the process by which an atom or a molecule acquires a negative or positive Electric charge, 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, electrons, positrons, protons, antiprotons, 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 occur within a fluorescent lamp or other electrical discharge lamps. It is also used in radiation detectors such as the Geiger- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
