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Zinc Antimonide
Zinc antimonide ( Zn Sb), ( Zn3 Sb2), ( Zn4 Sb3) is an inorganic chemical compound. The Zn-Sb system contains six intermetallics. Like indium antimonide, aluminium antimonide, and gallium antimonide, it is a semiconducting intermetallic compound. It is used in transistors, infrared detectors and thermal imagers, as well as magnetoresistive devices. History of Zinc Antimony Alloys and Zinc Antimonide The first reported use of zinc-antimony alloys was in the original work of T. J. Seebeck on thermoelectricity, a scientist who would then give his name to the Seebeck effect. By the 1860s, Moses G. Farmer, an American inventor, had developed the first high powered thermoelectric generator based on using a zinc-antimony alloy with a composition very close to stoichiometric ZnSb. He showed this generator at the 1867 Paris Exposition where it was carefully studied and copied (with minor modifications) by a number of people including Clamond. Farmer finally received the patent on his ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthorhombic
In crystallography, the orthorhombic crystal system is one of the 7 crystal systems. Orthorhombic lattices result from stretching a cubic lattice along two of its orthogonal pairs by two different factors, resulting in a rectangular prism with a rectangular base (''a'' by ''b'') and height (''c''), such that ''a'', ''b'', and ''c'' are distinct. All three bases intersect at 90° angles, so the three lattice vectors remain mutually orthogonal. Bravais lattices There are four orthorhombic Bravais lattices: primitive orthorhombic, base-centered orthorhombic, body-centered orthorhombic, and face-centered orthorhombic. For the base-centered orthorhombic lattice, the primitive cell has the shape of a right rhombic prism;See , row oC, column Primitive, where the cell parameters are given as a1 = a2, α = β = 90° it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. Note that the length a of the primit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transistors
upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electrical power, power. The transistor is one of the basic building blocks of modern electronics. It is composed of semiconductor material, usually with at least three terminals for connection to an electronic circuit. A voltage or current applied to one pair of the transistor's terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Some transistors are packaged individually, but many more are found embedded in integrated circuits. Austro-Hungarian physicist Julius Edgar Lilienfeld proposed the concept of a field-effect transistor in 1926, but it was not possible to actually construc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Compounds
Zinc compounds are chemical compounds containing the element zinc which is a member of the group 12 of the periodic table. The oxidation state of zinc in most compounds is the group oxidation state of +2. Zinc may be classified as a post-transition main group element with zinc(II). Zinc compounds are noteworthy for their nondescript behavior, they are generally colorless (unlike other elements with the oxidation number +2, which are usually white), do not readily engage in redox reactions, and generally adopt symmetrical structures. General characteristics In its compounds, Zn2+ ions have an electronic configuration r3d10. As such, Zn2+ tends to have a symmetrical coordination geometry in both its complexes and compounds. In both ZnO and ZnS, (zincblende) zinc is bound tetrahedrally bound to four ligands (oxide and sulfide, respectively). Many complexes, such as ZnCl42−, are tetrahedral. Tetrahedrally coordinated zinc is found in metallo-enzymes such as carbonic anhydras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimonides
Antimonides (sometimes called stibnides) are Chemical compound, compounds of antimony with more electropositive elements. The antimonide ion is Sb3−. Reduction of antimony by alkali metals or by other methods leads to alkali metal antimonides of various types. Known antimonides include isolated Sb3− ions (in Li3Sb, Na3Sb), dumbbells Sb24− in Cs4Sb2, discrete antimony chains, for example, Sb68− in SrSb3, infinite spirals (Sb−)n (in NaSb, RbSb), planar four-membered rings Sb42−, Sb73− cages in Cs3Sb, and net shaped anions Sb32− in BaSb3. Some antimonides are semiconductors, e.g. those of the boron group such as indium antimonide. Many antimonides are flammable or decomposed by oxygen when heated since the antimonide ion is a reducing agent. References See also * Antimonide mineral Anions Antimonides {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mária Telkes
Mária Telkes (December 12, 1900 – December 2, 1995) was a Hungarian-American biophysicist and inventor who worked on solar energy technologies. She moved to the United States in 1925 to work as a biophysicist. She became an American citizen in 1937 and started work at the Massachusetts Institute of Technology to create practical uses of solar energy in 1939. During World War II, she developed a solar distillation device, deployed at the end of the war, which saved the lives of downed airmen and torpedoed sailors. Her goal was to create a version for villagers in poor and arid regions. Telkes, often called by colleagues The Sun Queen, is considered one of the founders of solar thermal storage systems. After the war, she became an associate research professor at MIT. In the 1940s she and architect Eleanor Raymond created one of the first solar-heated houses, Dover Sun House, by storing energy each day. In 1953 they created a solar oven for people at various latitudes that coul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exposition Universelle (1867)
The International Exposition of 1867 (french: Exposition universelle 'art et d'industriede 1867), was the second world's fair to be held in Paris, from 1 April to 3 November 1867. A number of nations were represented at the fair. Following a decree of Emperor Napoleon III, the exposition was prepared as early as 1864, in the midst of the renovation of Paris, marking the culmination of the Second French Empire. Visitors included Tsar Alexander II of Russia, a brother of the King William and Otto von Bismarck of Prussia, Prince Metternich and Franz Josef of Austria, Ottoman Sultan Abdülaziz, and the Khedive of Egypt Isma'il. Conception In 1864, Napoleon III issued a decree stating that an international exposition should be held in Paris in 1867. A commission was appointed with Prince Jerome Napoleon as president, under whose direction the preliminary work began. The site chosen for the Exposition Universelle of 1867 was the Champ de Mars, the great military parade ground ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moses G
Moses hbo, מֹשֶׁה, Mōše; also known as Moshe or Moshe Rabbeinu (Mishnaic Hebrew: מֹשֶׁה רַבֵּינוּ, ); syr, ܡܘܫܐ, Mūše; ar, موسى, Mūsā; grc, Mωϋσῆς, Mōÿsēs () is considered the most important prophet in Judaism and one of the most important prophets in Christianity, Islam, the Druze faith, the Baháʼí Faith and other Abrahamic religions. According to both the Bible and the Quran, Moses was the leader of the Israelites and lawgiver to whom the authorship, or "acquisition from heaven", of the Torah (the first five books of the Bible) is attributed. According to the Book of Exodus, Moses was born in a time when his people, the Israelites, an enslaved minority, were increasing in population and, as a result, the Egyptian Pharaoh worried that they might ally themselves with Egypt's enemies. Moses' Hebrew mother, Jochebed, secretly hid him when Pharaoh ordered all newborn Hebrew boys to be killed in order to reduce the population of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoelectric Effect
The thermoelectric effect is the direct conversion of temperature differences to electric voltage and vice versa via a thermocouple. A thermoelectric device creates a voltage when there is a different temperature on each side. Conversely, when a voltage is applied to it, heat is transferred from one side to the other, creating a temperature difference. At the atomic scale, an applied temperature gradient causes charge carriers in the material to diffuse from the hot side to the cold side. This effect can be used to generate electricity, measure temperature or change the temperature of objects. Because the direction of heating and cooling is affected by the applied voltage, thermoelectric devices can be used as temperature controllers. The term "thermoelectric effect" encompasses three separately identified effects: the Seebeck effect, Peltier effect, and Thomson effect. The Seebeck and Peltier effects are different manifestations of the same physical process; textbooks may re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Johann Seebeck
Thomas Johann Seebeck (; 9 April 1770 – 10 December 1831) was a Baltic German physicist, who, in 1822, observed a relationship between heat and magnetism. Later, in 1823, Ørsted called this phenomenon thermoelectric effect. Seebeck was born in Reval (today Tallinn) to a wealthy Baltic German merchant family. He received a medical degree in 1802 from the University of Göttingen, but preferred to study physics. From 1821 to 1823, Seebeck performed a series of experiments trying to understand Ørsted's findings from 1820. During his experiments, he observed that a junction of dissimilar metals produces a deflexion on a magnetic needle (compass) when exposed to a temperature gradient. Because Ørsted had discovered that an electric current produces a deflexion on a compass transversal to the wire, Seebeck's results were interpreted as a thermoelectric effect. This is now called the Peltier–Seebeck effect and is the basis of thermocouples and thermopiles. Seebeck effect In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor
A semiconductor is a material which has an electrical resistivity and conductivity, electrical conductivity value falling between that of a electrical conductor, conductor, such as copper, and an insulator (electricity), insulator, such as glass. Its electrical resistivity and conductivity, resistivity falls as its temperature rises; metals behave in the opposite way. Its conducting properties may be altered in useful ways by introducing impurities ("doping (semiconductor), doping") into the crystal structure. When two differently doped regions exist in the same crystal, a semiconductor junction is created. The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics. Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called "metalloid staircase" on the periodic table. After silicon, gallium arsenide is the second-most common s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthorhombic
In crystallography, the orthorhombic crystal system is one of the 7 crystal systems. Orthorhombic lattices result from stretching a cubic lattice along two of its orthogonal pairs by two different factors, resulting in a rectangular prism with a rectangular base (''a'' by ''b'') and height (''c''), such that ''a'', ''b'', and ''c'' are distinct. All three bases intersect at 90° angles, so the three lattice vectors remain mutually orthogonal. Bravais lattices There are four orthorhombic Bravais lattices: primitive orthorhombic, base-centered orthorhombic, body-centered orthorhombic, and face-centered orthorhombic. For the base-centered orthorhombic lattice, the primitive cell has the shape of a right rhombic prism;See , row oC, column Primitive, where the cell parameters are given as a1 = a2, α = β = 90° it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. Note that the length a of the primit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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