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Dynamical Diffraction
The dynamical theory of diffraction describes the interaction of waves with a regular lattice. The wave fields traditionally described are X-rays, neutrons or electrons and the regular lattice are atomic crystal structures or nanometer-scale multi-layers or self-arranged systems. In a wider sense, similar treatment is related to the interaction of light with optical band-gap materials or related wave problems in acoustics. The sections below deal with dynamical diffraction of X-rays. Principle The dynamical theory of diffraction considers the wave field in the periodic potential of the crystal and takes into account all multiple scattering effects. Unlike the kinematic theory of diffraction which describes the approximate position of Bragg or Laue diffraction peaks in reciprocal space, dynamical theory corrects for refraction, shape and width of the peaks, extinction and interference effects. Graphical representations are described in dispersion surfaces around reciprocal latti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refraction
In physics, refraction is the redirection of a wave as it passes from one transmission medium, medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenomenon, but other waves such as sound waves and Wind wave, water waves also experience refraction. How much a wave is refracted is determined by the change in wave speed and the initial direction of wave propagation relative to the direction of change in speed. Optical Prism (optics), prisms and Lens (optics), lenses use refraction to redirect light, as does the human eye. The refractive index of materials varies with the wavelength of light,R. Paschotta, article ochromatic dispersion in th, accessed on 2014-09-08 and thus the angle of the refraction also varies correspondingly. This is called dispersion (optics), dispersion and causes prism (optics), prisms and rainbows to divide white light into its constituent spectral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomalous Absorption
Anomaly or The Anomaly may refer to: Science Natural *Anomaly (natural sciences) ** Atmospheric anomaly ** Geophysical anomaly Medical *Congenital anomaly (birth defect), a disorder present at birth ** Physical anomaly, a deformation of an anatomical structure ***Congenital vertebral anomaly, any of several malformations of the spine **Collie eye anomaly, eye disease of dogs **Coronary artery anomaly, a congenital abnormality in the heart **Ebstein's anomaly, a congenital heart defect ** Uhl anomaly, a congenital heart disease affecting the myocardial muscle **Vaginal anomalies Biology * Anomalous, a species of moth in the Noctuid family *Chromosome anomaly, a disorder caused by a structural error in a chromosome or an atypical number of chromosomes * Genetic anomaly, a disorder caused by mutation *Teratology, the study of developmental anomalies Physics *Anomalous diffusion, the movement of molecules from a region of lower concentration to a region of higher concentration * A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kato Fringes
Kato or Katō may refer to: Places *Kato, Guyana, a village in Guyana *Katō, Hyōgo, a city in Hyōgo Prefecture, Japan *Katō District, Hokkaido, a district located in Tokachi Subprefecture, Hokkaido, Japan *Katowice, a city in Southern Poland, often abbreviated to Kato *Mankato, a city in Southern Minnesota, often abbreviated to Kato Brands and enterprises *Kato Airline, a small airline based in Evenes, Norway * Kato Airport, an airport in Guyana *Kato Precision Railroad Models, a manufacturer of model railroad equipment Fictional characters *Kato (The Green Hornet), comic book character *Kato, the main antagonist in Astrid Lindgren's book ''Mio, My Son'' *Cato Fong (originally spelled "Kato"), character from the ''Pink Panther'' film series, see list of The Pink Panther characters People * Kato (name), a given name and surname *Katō (surname), a Japanese surname Nickname or stage name *Kato (DJ), Danish DJ *Paul Diamond, Croatian professional wrestler Kato whose ring n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borrmann Triangle
Borrmann is a German surname. Notable people with the surname include: * Elmar Borrmann (born 1957), German fencer * Gerhard Borrmann (1908–2006), German physicist * Joachim Borrmann, recipient of Knight's Cross of the Iron Cross * Mechtild Borrmann (born 1960), German writer, author of several detective novels * Richard Borrmann (1852–1931), German architect and classical archaeologist *Robert Borrmann, birth name of Eniac, a German composer and record producer specializing in house music and techno * Bettina Borrmann Wells (1874–?), Bavarian-born English suffragette who toured the United States as an organizer and lecturer See also *the Borrmann effect The Borrmann effect (or Borrmann–Campbell effect after Gerhard Borrmann and Herbert N. Campbell) is the anomalous increase in the intensity of X-rays transmitted through a crystal when it is being set up for Bragg reflection. The Borrmann effec ... (after Gerhard Borrmann), the anomalous increase in the intensity of X-ray ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laue Geometry
Max Theodor Felix von Laue (; 9 October 1879 – 24 April 1960) was a German physicist who received the Nobel Prize in Physics in 1914 "for his discovery of the diffraction of X-rays by crystals". In addition to his scientific endeavors with contributions in optics, crystallography, quantum theory, superconductivity, and the theory of relativity, Laue had a number of administrative positions which advanced and guided German scientific research and development during four decades. A strong objector to Nazism, he was instrumental in re-establishing and organizing German science after World War II. Biography Early years Laue was born in Pfaffendorf, now part of Koblenz, Germany, to Julius Laue and Minna Zerrenner. In 1898, after passing his ''Abitur'' in Strassburg, he began his compulsory year of military service, after which in 1899 he started to study mathematics, physics, and chemistry at the University of Strassburg, the University of Göttingen, and the Ludwig Maximilia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bragg Geometry
Bragg may refer to: Places *Bragg City, Missouri, United States *Bragg, Texas, a ghost town, United States * Bragg, West Virginia, an unincorporated community, United States *Electoral district of Bragg, a state electoral district in South Australia, Australia * Mount Bragg, Queen Elizabeth Land, Antarctica * Bragg Islands, Graham Land, Antarctica * Bragg (crater), a crater on the Moon People and fictional characters * Bragg (surname), a list of people and fictional characters with the surname * Dobby Bragg, a pseudonym of American blues musician Roosevelt Sykes (1906–1983) Other uses * Bragg Institute, former name of the Australian Centre for Neutron Scattering, a neutron and X-ray scattering group in Australia * Bragg Communications, a Canadian cable television provider *Bragg Live Food Products, Inc, a health food company started by Paul Bragg *Bragg Memorial Stadium, a football stadium in Tallahassee, Florida See also *Bragg Box, a type of traveling museum exhibit invented ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pendellösung
The Pendellösung effect or phenomenon is seen in diffraction in which there is a beating in the intensity of electromagnetic waves travelling within a crystal lattice. It was predicted by P. P. Ewald in 1916 and first observed in electron diffraction of magnesium oxide in 1942 by Robert D. Heidenreich and in X-ray diffraction by Norio Kato and Andrew Richard Lang in 1959. At the exit surface of a photonic crystal (PhC), the intensity of the diffracted wave can be periodically modulated, showing a maximum in the "positive" (forward diffracted) or in the "negative" (diffracted) direction, depending on the crystal slab thickness. The Pendellösung effect in photonic crystal A photonic crystal is an optical nanostructure in which the refractive index changes periodically. This affects the propagation of light in the same way that the structure of Crystal structure, natural crystals gives rise to X-ray crystallograp ...s can be understood as a beating phenomenon due to the phas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Band Gap
In solid-state physics and solid-state chemistry, a band gap, also called a bandgap or energy gap, is an energy range in a solid where no electronic states exist. In graphs of the electronic band structure of solids, the band gap refers to the energy difference (often expressed in electronvolts) between the top of the valence band and the bottom of the conduction band in insulators and semiconductors. It is the energy required to promote an electron from the valence band to the conduction band. The resulting conduction-band electron (and the electron hole in the valence band) are free to move within the crystal lattice and serve as charge carriers to conduct electric current. It is closely related to the HOMO/LUMO gap in chemistry. If the valence band is completely full and the conduction band is completely empty, then electrons cannot move within the solid because there are no available states. If the electrons are not free to move within the crystal lattice, then there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy
Energy () is the physical quantity, quantitative physical property, property that is transferred to a physical body, body or to a physical system, recognizable in the performance of Work (thermodynamics), work and in the form of heat and light. Energy is a Conservation law, conserved quantity—the law of conservation of energy states that energy can be Energy transformation, converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J). Forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a Classical field theory, field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, the internal energy contained within a thermodynamic system, and rest energy associated with an object's rest mass. These are not mutual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darwin Plateau
Darwin Plateau is a mostly circular, small plateau, about 0.75 mi to 1.25 miles in diameter surrounding the base of Mount Huethawali; the Huethawali prominence occupies about one quarter of the Darwin Plateau. South of the prominence, the Darwin Plateau borders Huethawali on the southwest, south, and southeast, with the southwest forming a saddle (landform), saddle between Garnet Canyon (Upper Canyon, and the northeast of Drummond Plateau), the southwest terminus of the Grand Scenic Divide, and east, the saddle at the headwaters of the southwest terminus of Upper Bass Canyon (the location of the South Bass Trail). The Darwin Plateau is about 0.75 miles northwest of the southwest terminus of the Grand Scenic Divide, and is located about 2.0 miles east of excursions of the Colorado River. North of Mount Huethawali are two landforms identical in approximate elevations to Darwin Plateau, namely Spencer Terrace, north-northwest, and Huxley Terrace, northeast (the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
