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Erbium
Erbium is a chemical element; it has Symbol (chemistry), symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements. It is a lanthanide, a rare-earth element, originally found in the gadolinite mine in Ytterby, Sweden, which is the source of the element's name. Erbium's principal uses involve its pink-colored Er3+ ions, which have optical fluorescent properties particularly useful in certain laser applications. Erbium-doped glasses or crystals can be used as optical amplification media, where Er3+ ions are optically pumped at around 980 or and then radiate light at in stimulated emission. This process results in an unusually mechanically simple laser optical amplifier for signals transmitted by fiber optics. The wavelength is especially important for optical communications because standard single mode optical fibers have minimal loss at this particular wavelength. In addition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erbium(III)chloride Sunlight
Erbium is a chemical element; it has symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements. It is a lanthanide, a rare-earth element, originally found in the gadolinite mine in Ytterby, Sweden, which is the source of the element's name. Erbium's principal uses involve its pink-colored Er3+ ions, which have optical fluorescent properties particularly useful in certain laser applications. Erbium-doped glasses or crystals can be used as optical amplification media, where Er3+ ions are optically pumped at around 980 or and then radiate light at in stimulated emission. This process results in an unusually mechanically simple laser optical amplifier for signals transmitted by fiber optics. The wavelength is especially important for optical communications because standard single mode optical fibers have minimal loss at this particular wavelength. In addition to optical fiber amp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erbia
Erbium(III) oxide is the inorganic compound with the formula . It is a pink paramagnetic solid. It finds uses in various optical materials. Structure Erbium(III) oxide has a cubic structure resembling the bixbyite motif. The Er3+ centers are octahedral. Reactions Erbium oxide is produced by burning erbium metal. Erbium oxide is insoluble in water but soluble in mineral acids. Er2O3 does not readily absorb moisture and carbon dioxide from the atmosphere. It can react with acids to form the corresponding erbium(III) salts. For example, with hydrochloric acid, the oxide follows the following idealized reaction leading to erbium chloride: : In practice, such simple acid-base reactions are accompanied by hydration: : Properties One interesting property of erbium oxides is their ability to up convert photons. Photon upconversion takes place when infrared or visible radiation, low energy light, is converted to ultraviolet or violet radiation higher energy light via multiple tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanthanide
The lanthanide () or lanthanoid () series of chemical elements comprises at least the 14 metallic chemical elements with atomic numbers 57–70, from lanthanum through ytterbium. In the periodic table, they fill the 4f orbitals. Lutetium (element 71) is also sometimes considered a lanthanide, despite being a d-block element and a transition metal. The informal chemical symbol Ln is used in general discussions of lanthanide chemistry to refer to any lanthanide. All but one of the lanthanides are f-block elements, corresponding to the filling of the 4f electron shell. Lutetium is a d-block element (thus also a transition metal), and on this basis its inclusion has been questioned; however, like its congeners scandium and yttrium in group 3, it behaves similarly to the other 14. The term rare-earth element or rare-earth metal is often used to include the stable group 3 elements Sc, Y, and Lu in addition to the 4f elements. All lanthanide elements form trivalent cations, Ln3+, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Amplifier
An optical amplifier is a device that amplifies an optical signal directly, without the need to first convert it to an electrical signal. An optical amplifier may be thought of as a laser without an optical cavity, or one in which feedback from the cavity is suppressed. Optical amplifiers are important in optical communication and laser physics. They are used as optical repeaters in the long distance fiber-optic cables which carry much of the world's telecommunication links. There are several different physical mechanisms that can be used to amplify a light signal, which correspond to the major types of optical amplifiers. In doped fiber amplifiers and bulk lasers, stimulated emission in the amplifier's gain medium causes amplification of incoming light. In semiconductor optical amplifiers (SOAs), electron–hole recombination occurs. In Raman amplifiers, Raman scattering of incoming light with phonons in the lattice of the gain medium produces photons coherent with th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Laser
A dental laser is a type of laser designed specifically for use in oral surgery or dentistry. In the United States, the use of lasers on the gums was first approved by the Food and Drug Administration in the early 1990s, and use on hard tissue like teeth or the bone of the mandible gained approval in 1996. Several variants of dental lasers are in use with different wavelengths and these mean they are better suited for different applications. Soft tissue lasers * Diode lasers *Carbon dioxide lasers * Nd:YAG laser Diode lasers wavelengths in the 810–1,100 nm range are poorly absorbed by the soft tissues such as the gingivae, and cannot be used for soft tissue cutting or ablation. Instead, the distal end of diode's glass fiber is charred (by burned ink or by burned corkwood, etc.) and the char is heated by the 810-1,100 nm laser beam, which in turn heats up the glass fiber's tip. The soft tissue is cut, on contact, by the hot charred glass tip and not by the laser beam itself ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbol (chemistry)
Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols, normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised. History Earlier symbols for chemical elements stem from classical Latin and Greek words. For some elements, this is because the material was known in ancient times, while for others, the name is a more recent invention. For example, Pb is the symbol for lead (''plumbum'' in Latin); Hg is the symbol for mercury (''hydrargyrum'' in Greek); and He is the symbol for helium (a Neo-Latin name) because helium was not known in ancient Roman times. Some symbols come from other sources, like W for tungsten (''Wolfram'' in German) which was not known in Roman times. A three-letter temporary symbol may be assigned to a newly synthesized (or not yet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Surgery
Laser surgery is a type of surgery that cuts tissue using a laser in contrast to using a scalpel. Soft-tissue laser surgery is used in a variety of applications in humans ( general surgery, neurosurgery, ENT, dentistry, orthodontics, and oral and maxillofacial surgery) as well as veterinary surgical fields. The primary uses of lasers in soft tissue surgery are to cut, ablate, vaporize, and coagulate. There are several different laser wavelengths used in soft tissue surgery. Different laser wavelengths and device settings (such as pulse duration and power) produce different effects on the tissue. Some commonly used lasers types in soft tissue surgery include erbium, diode, and CO2. Erbium lasers are excellent cutters, but provide minimal hemostasis. Diode lasers (hot tip) provide excellent hemostasis, but are slow cutters. CO2 lasers are both efficient at cutting and coagulating. Laser surgery is commonly used on the eye. Techniques used include LASIK, which is used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rare-earth Metals
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. Compounds containing rare earths have diverse applications in electrical and electronic components, lasers, glass, magnetic materials, and industrial processes. The term "rare-earth" is a misnomer because they are not actually scarce, but historically it took a long time to isolate these elements. They are relatively plentiful in the entire Earth's crust (cerium being the 25th-most-abundant element at 68 parts per million, more abundant than copper), but in practice they are spread thinly as trace impurities, so to obtain rare earths at usable purity requires processing enormous amounts of raw ore at great expense; thus the name "rare" earths. Scandium and yttrium are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow and the optical amplifier patented by Gordon Gould. A laser differs from other sources of light in that it emits light that is coherence (physics), ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling uses such as optical communication, laser cutting, and Photolithography#Light sources, lithography. It also allows a laser beam to stay narrow over great distances (collimated light, collimation), used in laser pointers, lidar, and free-space optical communication. Lasers can also have high temporal coherence, which permits them to emit light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rare-earth Element
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. Compounds containing rare earths have diverse applications in electrical and electronic components, lasers, glass, magnetic materials, and industrial processes. The term "rare-earth" is a misnomer because they are not actually scarce, but historically it took a long time to isolate these elements. They are relatively plentiful in the entire Earth's crust (cerium being the 25th-most-abundant element at 68 parts per million, more abundant than copper), but in practice they are spread thinly as trace impurities, so to obtain rare earths at usable purity requires processing enormous amounts of raw ore at great expense; thus the name "rare" earths. Scandium and yttrium are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolism
Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks of proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their Structures#Biological, structures, and respond to their environments. The word ''metabolism'' can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary (or intermediate) metabolism. Metabolic reactions may be categorized as ''catabolic''—the ''breaking down'' of compounds (for example, of glucose to pyruvate by c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absorption Spectra
Absorption may refer to: Chemistry and biology * Absorption (biology), digestion ** Absorption (small intestine) * Absorption (chemistry), diffusion of particles of gas or liquid into liquid or solid materials * Absorption (skin), a route by which substances enter the body through the skin * Absorption (pharmacology), absorption of drugs into the body Physics and chemical engineering * Absorption (acoustics), absorption of sound waves by a material *Absorption (electromagnetic radiation) In physics, absorption of electromagnetic radiation is how matter (typically electrons bound in atoms) takes up a photon's energy—and so transforms electromagnetic energy into internal energy of the absorber (for example, thermal energy). ..., absorption of light or other electromagnetic radiation by a material *Absorption air conditioning, a type of solar air conditioning * Absorption refrigerator, a refrigerator that runs on surplus heat rather than electricity * Dielectric absorptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
