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Neodymium Magnet Lifting Spheres
Neodymium is a chemical element; it has symbol Nd and atomic number 60. It is the fourth member of the lanthanide series and is considered to be one of the rare-earth metals. It is a hard, slightly malleable, silvery metal that quickly tarnishes in air and moisture. When oxidized, neodymium reacts quickly producing pink, purple/blue and yellow compounds in the +2, +3 and +4 oxidation states. It is generally regarded as having one of the most complex spectra of the elements. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach, who also discovered praseodymium. Neodymium is present in significant quantities in the minerals monazite and bastnäsite. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use. Neodymium is fairly common—about as common as cobalt, nickel, or copper—and is widely distributed in the Earth's crust. Most of the world's commercial neodymium is mined in China ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Element
A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its atomic nucleus, nucleus. Atoms of the same element can have different numbers of neutrons in their nuclei, known as isotopes of the element. Two or more atoms can combine to form molecules. Some elements form Homonuclear molecule, molecules of atoms of said element only: e.g. atoms of hydrogen (H) form Diatomic molecule, diatomic molecules (H). Chemical compounds are substances made of atoms of different elements; they can have molecular or non-molecular structure. Mixtures are materials containing different chemical substances; that means (in case of molecular substances) that they contain different types of molecules. Atoms of one element can be transformed into atoms of a different element in nuclear reactions, which change an atom's at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abundance Of Elements In Earth's Crust
The abundance of elements in Earth's crust is shown in tabulated form with the estimated Earth's crust, crustal abundance for each chemical element shown as mg/kg, or parts-per notation, parts per million (ppm) by mass (10,000 ppm = 1%). Reservoirs The Earth's crust is one "reservoir" for measurements of abundance. A reservoir is any large body to be studied as unit, like the ocean, atmosphere, mantle or crust. Different reservoirs may have different relative amounts of each element due to different chemical or mechanical processes involved in the creation of the reservoir. Difficulties in measurement Estimates of elemental abundance are difficult because (a) the composition of the upper and lower crust are quite different, and (b) the composition of the continental crust can vary drastically by locality. The composition of the Earth changed after its formation due to loss of volatile compounds, melting and recrystalization, selective loss of some elements to the deep in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YAG Laser
YAG, YaG, Yağ, or yag can refer to: * Yttrium aluminium garnet, a synthetic crystal used in solid-state laser systems * Fort Frances Municipal Airport, Ontario, Canada, IATA code * YMCA Youth and Government, a model government program for youth * Yahgan language, spoken in Chile and Argentina, ISO 639 code * Cansu Yağ (born 1990), a female Turkish footballer * YAG training vessels, wooden Canadian Navy boats 1954–1955 * List of yard and district craft of the United States Navy#District auxiliary, miscellaneous (YAG), District auxiliary, miscellaneous (YAG), US Navy hull classification symbol {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yttrium Aluminium Garnet
Yttrium aluminium garnet (YAG, Yttrium, Y3Aluminium, Al5Oxygen, O12) is a synthetic crystalline material of the garnet group. It is a Crystal system, cubic yttrium aluminium oxide phase, with other examples being YAlO3 (YAP) in a Crystal system, hexagonal or an orthorhombic, perovskite-like form, and the monoclinic Y4Al2O9 (YAM). Due to its broad optical transparency, low internal stress, high hardness, chemical and heat resistance, YAG is used for a variety of optics. Its lack of birefringence (unlike sapphire) makes it an interesting material for high-energy/high-power laser systems. Laser damage threshold, Laser damage levels of YAG ranged from 1.1 to 2.2 kJ/cm2 (1064 nm, 10 ns). YAG, like garnet and sapphire, has no uses as a laser medium when pure. However, after being doped with an appropriate ion, YAG is commonly used as a host material in various solid-state lasers. Rare earth elements such as neodymium and erbium can be doping (semiconductors), doped into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (materials Science)
Substrate is a term used in materials science and engineering to describe the base material on which processing is conducted. Surfaces have different uses, including producing new film or layers of material and being a base to which another substance is bonded. Description In materials science and engineering, a substrate refers to a base material on which processing is conducted. This surface could be used to produce new film or layers of material such as deposited coatings. It could be the base to which paint, adhesives, or adhesive tape is bonded. A typical substrate might be rigid such as metal, concrete, or glass, onto which a coating might be deposited. Flexible substrates are also used. Some substrates are anisotropic with surface properties being different depending on the direction: examples include wood and paper products. Coatings With all coating processes, the condition of the surface of the substrate can strongly affect the bond of subsequent layers. This c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inertial Confinement Fusion
Inertial confinement fusion (ICF) is a fusion energy process that initiates nuclear fusion reactions by compressing and heating targets filled with fuel. The targets are small pellets, typically containing deuterium (2H) and tritium (3H). Typically, short pulse lasers deposit energy on a hohlraum. Its inner surface vaporizes, releasing X-rays. These converge on the pellet's exterior, turning it into a plasma. This produces a reaction force in the form of shock waves that travel through the target. The waves compress and heat it. Sufficiently powerful shock waves achieve the Lawson criterion for fusion of the fuel. ICF is one of two major branches of fusion research; the other is magnetic confinement fusion (MCF). When first proposed in the early 1970s, ICF appeared to be a practical approach to power production and the field flourished. Experiments demonstrated that the efficiency of these devices was much lower than expected. Throughout the 1980s and '90s, experiments were co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopant
A dopant (also called a doping agent) is a small amount of a substance added to a material to alter its physical properties, such as electrical or optics, optical properties. The amount of dopant is typically very low compared to the material being doped. When doped into crystalline substances, the dopant's atoms get incorporated into the crystal lattice of the substance. The crystalline materials are frequently either crystals of a semiconductor such as silicon and germanium for use in solid-state electronics, or transparency and translucency, transparent crystals for use in the production of various laser types; however, in some cases of the latter, noncrystalline substances such as glass can also be doped with impurities. In solid-state electronics using the proper types and amounts of dopants in semiconductors is what produces the p-type semiconductors and n-type semiconductors that are essential for making transistors and diodes. Transparent crystals Lasing media The p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terbium
Terbium is a chemical element; it has Symbol (chemistry), symbol Tb and atomic number 65. It is a silvery-white, rare earth element, rare earth metal that is malleable and ductile. The ninth member of the lanthanide series, terbium is a fairly electropositive metal that reacts with water, evolving hydrogen gas. Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime and euxenite. Swedish chemist Carl Gustaf Mosander discovered terbium as a chemical element in 1843. He detected it as an impurity in Yttrium(III) oxide, yttrium oxide (). Yttrium and terbium, as well as erbium and ytterbium, are named after the village of Ytterby in Sweden. Terbium was not isolated in pure form until the advent of ion exchange techniques. Terbium is used to dopant, dope calcium fluoride, calcium tungstate and strontium molybdate in solid-state devices, and as a crystal stabilizer of fuel cells that operate at elevated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europium
Europium is a chemical element; it has symbol Eu and atomic number 63. It is a silvery-white metal of the lanthanide series that reacts readily with air to form a dark oxide coating. Europium is the most chemically reactive, least dense, and softest of the lanthanides. It is soft enough to be cut with a knife. Europium was discovered in 1896, provisionally designated as Σ; in 1901, it was named after the continent of Europe. Europium usually assumes the oxidation state +3, like other members of the lanthanide series, but compounds having oxidation state +2 are also common. All europium compounds with oxidation state +2 are slightly reducing. Europium has no significant biological role and is relatively non-toxic compared to other heavy metals. Most applications of europium exploit the phosphorescence of europium compounds. Europium is one of the rarest of the rare-earth elements on Earth.Stwertka, Albert. ''A Guide to the Elements'', Oxford University Press, 1996, p. 156. Ety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (element)
Mercury is a chemical element; it has Symbol (chemistry), symbol Hg and atomic number 80. It is commonly known as quicksilver. A Heavy metal element, heavy, silvery d-block element, mercury is the only metallic element that is known to be liquid at standard temperature and pressure; the only other element that is liquid under these conditions is the halogen bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature. Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide). The red pigment vermilion is obtained by Mill (grinding), grinding natural cinnabar or synthetic mercuric sulfide. Exposure to mercury and mercury-containing organic compounds is toxic to the nervous system, immune system and kidneys of humans and other animals; mercury poisoning can result from exposure to water-soluble forms of mercury (such as mercuric chloride or methylmercury) either directly or through mechanisms of biomagnification. Mercu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass
Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window panes, tableware, and optics. Some common objects made of glass are named after the material, e.g., a Tumbler (glass), "glass" for drinking, "glasses" for vision correction, and a "magnifying glass". Glass is most often formed by rapid cooling (quenching) of the Melting, molten form. Some glasses such as volcanic glass are naturally occurring, and obsidian has been used to make arrowheads and knives since the Stone Age. Archaeological evidence suggests glassmaking dates back to at least 3600 BC in Mesopotamia, Ancient Egypt, Egypt, or Syria. The earliest known glass objects were beads, perhaps created accidentally during metalworking or the production of faience, which is a form of pottery using lead glazes. Due to its ease of formability int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken or new bonds formed or both. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
