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Moritz Ludwig Frankenheim
Moritz Ludwig Frankenheim (29 June 1801 – 14 January 1869) was a Germans, German physicist, geographer, and crystallography, crystallographer. Life and education Moritz Ludwig Frankenheim was born in 1801 in Braunschweig, Brunswick. His family was Jewish.Ismar Schorsch, ''Leopold Zunz: Creativity in Adversity'', University of Pennsylvania Press (2016), p. 26 He attended the ''Gymnasium'' (high school) there and in Wolfenbüttel. Afterwards he went to Berlin to attend the ''Alma Mater Berolinensis'' (today Humboldt University of Berlin) to study physics. In 1823 he completed a dissertation titled ''Dissertatio de Theoria Gasorum et Vaporum Meditationes'' ("Contemplations on the scientific theory of gases and vapors"). Inspired by the research of his teacher Christian Samuel Weiss (1780-1856), he became interested in crystallography. In 1827 he moved to the University of Breslau, where he was assistant professor of physics, geography, and mathematics from 1827 to 1850. In 185 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Braunschweig
Braunschweig () or Brunswick ( , from Low German ''Brunswiek'' , Braunschweig dialect: ''Bronswiek'') is a city in Lower Saxony, Germany, north of the Harz Mountains at the farthest navigable point of the river Oker, which connects it to the North Sea via the rivers Aller and Weser. In 2016, it had a population of 250,704. A powerful and influential centre of commerce in medieval Germany, Brunswick was a member of the Hanseatic League from the 13th until the 17th century. It was the capital city of three successive states: the Principality of Brunswick-Wolfenbüttel (1269–1432, 1754–1807, and 1813–1814), the Duchy of Brunswick (1814–1918), and the Free State of Brunswick (1918–1946). Today, Brunswick is the second-largest city in Lower Saxony and a major centre of scientific research and development. History Foundation and early history The date and circumstances of the town's foundation are unknown. Tradition maintains that Brunswick was created through the merge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographer
A geographer is a physical scientist, social scientist or humanist whose area of study is geography, the study of Earth's natural environment and human society, including how society and nature interacts. The Greek prefix "geo" means "earth" and the Greek suffix, "graphy," meaning "description," so a geographer is someone who studies the earth. The word "geography" is a Middle French word that is believed to have been first used in 1540. Although geographers are historically known as people who make maps, map making is actually the field of study of cartography, a subset of geography. Geographers do not study only the details of the natural environment or human society, but they also study the reciprocal relationship between these two. For example, they study how the natural environment contributes to human society and how human society affects the natural environment. In particular, physical geographers study the natural environment while human geographers study human society ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal System
In crystallography, a crystal system is a set of point groups (a group of geometric symmetries with at least one fixed point). A lattice system is a set of Bravais lattices. Space groups are classified into crystal systems according to their point groups, and into lattice systems according to their Bravais lattices. Crystal systems that have space groups assigned to a common lattice system are combined into a crystal family. The seven crystal systems are triclinic, monoclinic, orthorhombic, tetragonal, trigonal, hexagonal, and cubic. Informally, two crystals are in the same crystal system if they have similar symmetries (albeit there are many exceptions). Classifications Crystals can be classified in three ways: lattice systems, crystal systems and crystal families. The various classifications are often confused: in particular the trigonal crystal system is often confused with the rhombohedral lattice system, and the term "crystal system" is sometimes used to mean "latti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmetry Element
In chemistry and crystallography, a symmetry element is a point, line, or plane about which symmetry operations can take place. In particular, a symmetry element can be a mirror plane, an axis of rotation (either proper and improper), or a center of inversion. For an object such as a molecule or a crystal, a symmetry element corresponds to a set of symmetry operations, which are the rigid transformations employing the symmetry element that leave the object unchanged. The set containing these operations form one of the symmetry groups of the object. The elements of this symmetry group should not to be confused with the "symmetry element" itself. Loosely, a symmetry element is the geometric set of fixed points of a symmetry operation. For example, for rotation about an axis, the points on the axis do not move and in a reflection the points that remain unchanged make up a plane of symmetry. Identity The identity symmetry element is found in all objects and is denoted ''E''. It corre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miller Indices
Miller indices form a notation system in crystallography for lattice planes in crystal (Bravais) lattices. In particular, a family of lattice planes of a given (direct) Bravais lattice is determined by three integers ''h'', ''k'', and ''ℓ'', the ''Miller indices''. They are written (hkℓ), and denote the family of (parallel) lattice planes (of the given Bravais lattice) orthogonal to \mathbf_ = h\mathbf + k\mathbf + \ell\mathbf, where \mathbf are the basis or primitive translation vectors of the reciprocal lattice for the given Bravais lattice. (Note that the plane is not always orthogonal to the linear combination of direct or original lattice vectors h\mathbf + k\mathbf + \ell\mathbf because the direct lattice vectors need not be mutually orthogonal.) This is based on the fact that a reciprocal lattice vector \mathbf (the vector indicating a reciprocal lattice point from the reciprocal lattice origin) is the wavevector of a plane wave in the Fourier series of a spatia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Structure
In crystallography, crystal structure is a description of the ordered arrangement of atoms, ions or molecules in a crystal, crystalline material. Ordered structures occur from the intrinsic nature of the constituent particles to form symmetric patterns that repeat along the principal directions of Three-dimensional space (mathematics), three-dimensional space in matter. The smallest group of particles in the material that constitutes this repeating pattern is the unit cell of the structure. The unit cell completely reflects the symmetry and structure of the entire crystal, which is built up by repetitive Translation (geometry), translation of the unit cell along its principal axes. The translation vectors define the nodes of the Bravais lattice. The lengths of the principal axes, or edges, of the unit cell and the angles between them are the lattice constants, also called ''lattice parameters'' or ''cell parameters''. The symmetry properties of the crystal are described by the con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiplicative Inverse
In mathematics, a multiplicative inverse or reciprocal for a number ''x'', denoted by 1/''x'' or ''x''−1, is a number which when Multiplication, multiplied by ''x'' yields the multiplicative identity, 1. The multiplicative inverse of a rational number, fraction ''a''/''b'' is ''b''/''a''. For the multiplicative inverse of a real number, divide 1 by the number. For example, the reciprocal of 5 is one fifth (1/5 or 0.2), and the reciprocal of 0.25 is 1 divided by 0.25, or 4. The reciprocal function, the Function (mathematics), function ''f''(''x'') that maps ''x'' to 1/''x'', is one of the simplest examples of a function which is its own inverse (an Involution (mathematics), involution). Multiplying by a number is the same as Division (mathematics), dividing by its reciprocal and vice versa. For example, multiplication by 4/5 (or 0.8) will give the same result as division by 5/4 (or 1.25). Therefore, multiplication by a number followed by multiplication by its reciprocal yiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leipzig
Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as well as the second most populous city in the area of the former East Germany after (East) Berlin. Together with Halle (Saale), the city forms the polycentric Leipzig-Halle Conurbation. Between the two cities (in Schkeuditz) lies Leipzig/Halle Airport. Leipzig is located about southwest of Berlin, in the southernmost part of the North German Plain (known as Leipzig Bay), at the confluence of the White Elster River (progression: ) and two of its tributaries: the Pleiße and the Parthe. The name of the city and those of many of its boroughs are of Slavic origin. Leipzig has been a trade city since at least the time of the Holy Roman Empire. The city sits at the intersection of the Via Regia and the Via Imperii, two important medieval trad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retirement
Retirement is the withdrawal from one's position or occupation or from one's active working life. A person may also semi-retire by reducing work hours or workload. Many people choose to retire when they are elderly or incapable of doing their job due to health reasons. People may also retire when they are eligible for private or public pension benefits, although some are forced to retire when bodily conditions no longer allow the person to work any longer (by illness or accident) or as a result of legislation concerning their positions. In most countries, the idea of retirement is of recent origin, being introduced during the late-nineteenth and early-twentieth centuries. Previously, low life expectancy, lack of social security and the absence of pension arrangements meant that most workers continued to work until their death. Germany was the first country to introduce retirement benefits in 1889. Nowadays, most developed countries have systems to provide pensions on retirement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physics
Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events." Physics is one of the most fundamental scientific disciplines, with its main goal being to understand how the universe behaves. "Physics is one of the most fundamental of the sciences. Scientists of all disciplines use the ideas of physics, including chemists who study the structure of molecules, paleontologists who try to reconstruct how dinosaurs walked, and climatologists who study how human activities affect the atmosphere and oceans. Physics is also the foundation of all engineering and technology. No engineer could design a flat-screen TV, an interplanetary spacecraft, or even a better mousetrap without first understanding the basic laws of physic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolfenbüttel
Wolfenbüttel (; nds, Wulfenbüddel) is a town in Lower Saxony, Germany, the administrative capital of Wolfenbüttel District. It is best known as the location of the internationally renowned Herzog August Library and for having the largest concentration of timber-framed buildings in Germany. It is an episcopal see of the Evangelical Lutheran Church in Brunswick. It is also home to the Jägermeister distillery, houses a campus of the Ostfalia University of Applied Sciences, and the Landesmusikakademie of Lower Saxony. Geography The town center is located at an elevation of on the Oker river near the confluence with its Altenau tributary, about south of Brunswick and southeast of the state capital Hannover. Wolfenbüttel is situated about half-way between the Harz mountain range in the south and the Lüneburg Heath in the north. The Elm-Lappwald Nature Park and the Asse hill range stretch east and southeast of the town. With a population of about 52,000 people, Wolfe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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