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Cementation Furnace - Geograph
Cementation may refer to: * Cementation (biology), the process whereby some sessile bivalve mollusks (and some other shelled invertebrates) attach themselves permanently to a hard substrate *Cementation (geology), the process of deposition of dissolved mineral components in the interstices of sediments * Cementation (medical), a small deposit of calcium, similar to a cyst * Cementation (metallurgy), a process in which ions are reduced to zero valence at a solid metallic interface *Cementation process, an obsolete technique for making steel by carburization of iron *Carburization Carburising, carburizing (chiefly American English), or carburisation is a heat treatment process in which iron or steel absorbs carbon while the metal is heated in the presence of a carbon-bearing material, such as charcoal or carbon monoxide. ..., a process for surface hardening of low-carbon steel * Cementation Company, a British construction business {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalve Shell
A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk. In life, the shell of this class of mollusks is composed of two hinged parts or '' valves''. Bivalves are very common in essentially all aquatic locales, including saltwater, brackish water, and freshwater. The shells of bivalves commonly wash up on beaches (often as separate valves) and along the edges of lakes, rivers, and streams. Bivalves by definition possess two shells or ''valves'', a "right valve" and a "left valve", that are joined by a ligament. The two valves usually articulate with one another using structures known as "teeth" which are situated along the hinge line. In many bivalve shells, the two valves are symmetrical along the hinge line—when truly symmetrical, such an animal is said to be ''equivalved''; if the valves vary from each other in size or shape, ''inequivalved''. If symmetrical front-to-back, the valves are said to be ''equilateral'', and are otherwise considered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementation (geology)
Cementation involves ions carried in groundwater chemically precipitating to form new crystalline material between sedimentary grains. The new pore-filling minerals forms "bridges" between original sediment grains, thereby binding them together. In this way, ''sand'' becomes sandstone, and ''gravel'' becomes conglomerate or breccia. Cementation occurs as part of the diagenesis or lithification of sediments. Cementation occurs primarily below the water table regardless of sedimentary grain sizes present. Large volumes of pore water must pass through sediment pores for new mineral cements to crystallize and so millions of years are generally required to complete the cementation process. Common mineral cements include calcite, quartz, and silica phases like cristobalite, iron oxides, and clay minerals; other mineral cements also occur. Cementation is continuous in the groundwater zone, so much so that the term "zone of cementation" is sometimes used interchangeably. Cemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementation (medical)
Calcinosis cutis is a type of calcinosis wherein calcium deposits form in the skin. A variety of factors can result in this condition. The most common source is dystrophic calcification, which occurs in soft tissue as a response to injury. In addition, calcinosis is seen in Limited Cutaneous Systemic Sclerosis, also known as CREST syndrome (the "C" in CREST). In dogs, calcinosis cutis is found in young, large breed dogs and is thought to occur after a traumatic injury. Causes Calcinosis may result from a variety of causes such as: *Trauma to the region *Inflammation (bug bites, acne) * Varicose veins *Infections * Tumors (malignant or benign) *Diseases of connective tissue * Hypercalcemia * Hyperphosphatemia Calcinosis cutis is associated with systemic sclerosis. Diagnosis Types Calcinosis cutis may be divided into the following types: * Dystrophic calcinosis cutis * Metastatic calcinosis cutis * Iatrogenic calcinosis cutis * Traumatic calcinosis cutis * Idiopat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementation (metallurgy)
Cementation is a type of precipitation, a heterogeneous process in which ions are reduced to zero valence at a solid metallic interface. The process is often used to refine leach solutions. Cementation of copper is a common example. Copper ions in solution, often from an ore leaching process, are precipitated out of solution in the presence of solid iron. The iron oxidizes, and the copper ions are reduced through the transfer of electrons. The reaction is spontaneous because copper is higher on the galvanic series than iron. : Cu2+(aq) + Fe(s) → Cu(s) + Fe2+(aq) This was a historically useful process for the production of copper, where the precipitated solid copper metal was recovered as flakes or powder on the surface of scrap iron. Cementation is used industrially to recover a variety of heavy metals including cadmium, and the cementation of gold by zinc in the Merrill-Crowe process accounts for a substantial fraction of world gold production."Zinc cementation," R. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementation Process
The cementation process is an obsolete technology for making steel by carburization of iron. Unlike modern steelmaking, it increased the amount of carbon in the iron. It was apparently developed before the 17th century. Derwentcote Steel Furnace, built in 1720, is the earliest surviving example of a cementation furnace. Another example in the UK is the cementation furnace in Doncaster Street, Sheffield. Origins The process was described in a treatise published in Prague in 1574. It was again invented by Johann Nussbaum of Magdeburg, who began operations at Nuremberg (with partners) in 1601. The process was patented in England by William Ellyot and Mathias Meysey in 1614. At that date, the "invention" could consist merely of the introduction of a new industry or product, or even a mere monopoly. They evidently soon transferred the patent to Sir Basil Brooke, but he was forced to surrender it in 1619. A clause in the patent prohibiting the import of steel was foun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carburization
Carburising, carburizing (chiefly American English), or carburisation is a heat treatment process in which iron or steel absorbs carbon while the metal is heated in the presence of a carbon-bearing material, such as charcoal or carbon monoxide. The intent is to make the metal harder. Depending on the amount of time and temperature, the affected area can vary in carbon content. Longer carburizing times and higher temperatures typically increase the depth of carbon diffusion. When the iron or steel is cooled rapidly by quenching, the higher carbon content on the outer surface becomes hard due to the transformation from austenite to martensite, while the core remains soft and tough as a ferritic and/or pearlite microstructure.Oberg, E., Jones, F., and Ryffel, H. (1989) ''Machinery's Handbook 23rd Edition.'' New York: Industrial Press Inc. This manufacturing process can be characterized by the following key points: It is applied to low-carbon workpieces; workpieces are in con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
