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Pierre Victor Auger
Pierre Victor Auger (; 14 May 1899 – 24 December 1993) was a French physicist, born in Paris. He worked in the fields of atomic physics, nuclear physics, and cosmic ray physics. He is famous for being one of the discoverers of the Auger effect, named after him. Early life Pierre's father was chemistry professor Victor Auger. Pierre Auger was a student at the École normale supérieure in Paris from 1919 to 1922, the year when he passed the agrégation of physics. He then joined the physical chemistry laboratory of the faculté des sciences of the University of Paris under the direction of Jean Perrin to work there on the photoelectric effect. Career In 1926 he obtained his doctorate in physics from the University of Paris. In 1927, he was named assistant to the faculté des sciences of Paris and, at the same time, adjoint chief of service to l'Institut de biologie physico-chimique. Chief of work to faculty in 1934 and general secretary of the annual tables of the constants i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paris
Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Since the 17th century, Paris has been one of the world's major centres of finance, diplomacy, commerce, fashion, gastronomy, and science. For its leading role in the arts and sciences, as well as its very early system of street lighting, in the 19th century it became known as "the City of Light". Like London, prior to the Second World War, it was also sometimes called the capital of the world. The City of Paris is the centre of the Île-de-France region, or Paris Region, with an estimated population of 12,262,544 in 2019, or about 19% of the population of France, making the region France's primate city. The Paris Region had a GDP of €739 billion ($743 billion) in 2019, which is the highest in Europe. According to the Economist Intelli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agrégation
In France, the ''agrégation'' () is a competitive examination for civil service in the French public education system. Candidates for the examination, or ''agrégatifs'', become ''agrégés'' once they are admitted to the position of ''professeur agrégé''. In France, ''professeurs agrégés'' are distinguished from ''professeurs certifiés'' recruited through the CAPES training. The ''agrégés'' are usually expected to teach in sixth-form colleges (''lycées'') and universities, while the ''certifiés'' usually teach in secondary schools (''collèges''), although there is a significant overlap. The examination may require more than a year of preparation. The difficulty and selectivity (quota) vary from one discipline to another: there are about 300 such positions open each year for mathematics alone, but usually fewer positions are made available for humanities and social sciences (for example, 61 positions for philosophy were offered in 2018) and perhaps only one seat in som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronvolt
In physics, an electronvolt (symbol eV, also written electron-volt and electron volt) is the measure of an amount of kinetic energy In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acc ... gained by a single electron accelerating from rest through an Voltage, electric potential difference of one volt in vacuum. When used as a Units of energy, unit of energy, the numerical value of 1 eV in joules (symbol J) is equivalent to the numerical value of the Electric charge, charge of an electron in coulombs (symbol C). Under the 2019 redefinition of the SI base units, this sets 1 eV equal to the exact value Historically, the electronvolt was devised as a standard unit of measure through its usefulness in Particle accelerator#Electrostatic particle accelerators, electrostatic particle accel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Shower (physics)
An air shower is an extensive (many kilometres wide) cascade of ionized particles and electromagnetic radiation produced in the atmosphere when a ''primary'' cosmic ray (i.e. one of extraterrestrial origin) enters the atmosphere. When a particle, which could be a proton, a nucleus, an electron, a photon, or (rarely) a positron, strikes an atom's nucleus in the air it produces many energetic hadrons. The unstable hadrons decay in the air speedily into other particles and electromagnetic radiation, which are part of the particle shower components. The secondary radiation rains down, including x-rays, muons, protons, antiprotons, alpha particles, pions, electrons, positrons, and neutrons. The dose from cosmic radiation is largely from muons, neutrons, and electrons, with a dose rate that varies in different parts of the world and based largely on the geomagnetic field, altitude, and solar cycle. Airline crews receive more cosmic rays if they routinely work flight routes that take ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmic Ray
Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our own galaxy, and from distant galaxies. Upon impact with Earth's atmosphere, cosmic rays produce showers of secondary particles, some of which reach the surface, although the bulk is deflected off into space by the magnetosphere or the heliosphere. Cosmic rays were discovered by Victor Hess in 1912 in balloon experiments, for which he was awarded the 1936 Nobel Prize in Physics. Direct measurement of cosmic rays, especially at lower energies, has been possible since the launch of the first satellites in the late 1950s. Particle detectors similar to those used in nuclear and high-energy physics are used on satellites and space probes for research into cosmic rays. Data from the Fermi Space Telescope (2013) have been interpreted as evidenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lise Meitner
Elise Meitner ( , ; 7 November 1878 – 27 October 1968) was an Austrian-Swedish physicist who was one of those responsible for the discovery of the element protactinium and nuclear fission. While working at the Kaiser Wilhelm Institute on radioactivity, she discovered the radioactive isotope protactinium-231 in 1917. In 1938, Meitner and her nephew, the physicist Otto Robert Frisch, discovered nuclear fission. She was praised by Albert Einstein as the "German Marie Curie". Completing her doctoral research in 1905, Meitner became the second woman from the University of Vienna to earn a doctorate in physics. She spent most of her scientific career in Berlin, Germany, where she was a physics professor and a department head at the Kaiser Wilhelm Institute; she was the first woman to become a full professor of physics in Germany. She lost these positions in the 1930s because of the anti-Jewish Nuremberg Laws of Nazi Germany, and in 1938 she fled to Sweden, where she lived for many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atom
Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics, as if they were tennis balls for example, is not possible due to quantum effects. More than 99.94% of an atom's mass is in the nucleus. The protons have a positive electric charge, the electrons have a negative electric charge, and the neutrons have no electric charge. If the number of protons and electrons are equal, then the atom is electrically neutral. If an atom has more or fewer electrons than protons, then it has an overall negative or positive charge, respectively – such atoms are called ions. The electrons of an atom are a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auger Electron
The Auger effect or Auger−Meitner effect is a physical phenomenon in which the filling of an inner-shell vacancy of an atom is accompanied by the emission of an electron from the same atom. When a core electron is removed, leaving a vacancy, an electron from a higher energy level may fall into the vacancy, resulting in a release of energy. Although most often this energy is released in the form of an emitted photon, the energy can also be transferred to another electron, which is ejected from the atom; this second ejected electron is called an Auger electron. Effect The effect was first discovered by Lise Meitner in 1922; Pierre Victor Auger independently discovered the effect shortly after and is credited with the discovery in most of the scientific community. Upon ejection, the kinetic energy of the Auger electron corresponds to the difference between the energy of the initial electronic transition into the vacancy and the ionization energy for the electron shell from which t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boris Ephrussi
Boris Ephrussi (russian: Борис Самойлович Эфрусси; 9 May 1901 – 2 May 1979), Professor of Genetics at the University of Paris, was a Russo- French geneticist. Boris was born on 9 May 1901 into a Jewish family. His father, Samuel Osipovich Ephrussi, was a chemical engineer; his grandfather, Joseph Ephrusi (Efrusi), was the founder of a banking dynasty in Kishinev. He published two papers in November 1966 which represented a key step in a decade of research in his laboratory. This research helped transform mammalian, and especially human, genetics. Boris started his scientific training as a Russian émigré in 1920. He studied the initiation and regulation of embryological processes by intracellular and extracellular factors. A major strand of his early research concerned the effect of temperature on the development of fertilized sea urchin eggs. In this work he used a micromanipulator, which was developed by Robert Chambers, an American biologist. During ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sorbonne University
Sorbonne University (french: Sorbonne Université; la Sorbonne: 'the Sorbonne') is a public research university located in Paris, France. The institution's legacy reaches back to 1257 when Sorbonne College was established by Robert de Sorbon as one of the first universities in Europe. Sorbonne University is considered one of the most prestigious universities in Europe and the world. It has a world-class reputation in academia and industry; as of 2021, its alumni and professors have won 33 Nobel Prizes, six Fields Medals, and one Turing Award. In the 2021 edition of the '' Academic Ranking of World Universities'', Sorbonne University ranked 35th in the world, placing it as the 4th best university in continental Europe, 3rd in Mathematics and Oceanography. In the 2023 edition of ''QS World University Rankings'', the Sorbonne ranked 60th in the world, placing it 8th in continental Europe, 14th in Natural Sciences and Mathematics, and 7th in Classics and Ancient History. K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance), and within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
