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Lamella (materials)
A ''lamella'' (plural ''lamellae'') is a small plate or flake, from the Latin, and may also be used to refer to collections of fine sheets of material held adjacent to one another, in a gill-shaped structure, often with fluid in between though sometimes simply a set of 'welded' plates. The term is used in biological contexts to describe thin membranes of plates of tissue. In context of materials science, the microscopic structures in bone and nacre are called lamellae. Moreover, the term lamella is often used as a way to describe crystal structure of some materials. Uses of the term In surface chemistry (especially mineralogy and materials science), lamellar structures are fine layers, alternating between different materials. They can be produced by chemical effects (as in eutectic solidification), biological means, or a deliberate process of lamination, such as pattern welding. Lamellae can also describe the layers of atoms in the crystal lattices of materials such as me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill
A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia (pl. branchiae) is the zoologists' name for gills (from Ancient Greek ). With the exception of some aquatic insects, the filaments and lamellae (folds) contain blood or coelomic fluid, from which gases are exchanged through the thin walls. The blood carries oxygen to other parts of the body. Carbon dioxide passes from the blood through the thin gill tissue into the water. Gills or gill-like organs, located in different parts of the body, are found in various groups of aquatic animals, including mollusks, crustaceans, insects, fish, and amphibians. Semiterrestrial marine animals such as crabs and mudskippers have gill cham ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Exchanger
A heat exchanger is a system used to transfer heat between a source and a working fluid. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants, petrochemical plants, petroleum refineries, natural-gas processing, and sewage treatment. The classic example of a heat exchanger is found in an internal combustion engine in which a circulating fluid known as engine coolant flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air. Another example is the heat sink, which is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant. Flow arrangement Image:Heat_exc_1-1.svg, Fig. 1: Shell and tube heat exchanger, single pass (1–1 parallel f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyosis
Ichthyosis is a family of genetic skin disorders characterized by dry, thickened, scaly skin. The more than 20 types of ichthyosis range in severity of symptoms, outward appearance, underlying genetic cause and mode of inheritance (e.g., dominant, recessive, autosomal or X-linked). Ichthyosis comes from the Greek ἰχθύς ''ichthys'', literally "fish", since dry, scaly skin is the defining feature of all forms of ichthyosis. The severity of symptoms can vary enormously, from the mildest, most common, types such as ichthyosis vulgaris, which may be mistaken for normal dry skin, up to life-threatening conditions such as harlequin-type ichthyosis. Ichthyosis vulgaris accounts for more than 95% of cases. Types Many types of ichthyoses exist, and an exact diagnosis may be difficult. Types of ichthyoses are classified by their appearance, if they are syndromic or not, and by mode of inheritance. For example, non-syndromic ichthyoses that are inherited recessively come under the um ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water-treatment
Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment. Water treatment removes contaminants and undesirable components, or reduces their concentration so that the water becomes fit for its desired end-use. This treatment is crucial to human health and allows humans to benefit from both drinking and irrigation use. Water is the most crucial compound for life on Earth, and having drinkable water is a key worldwide concern for the twenty-first century. All living things require clean, uncontaminated water as a basic requirement. Water covers more than 71 percent of the earth’s surface, but only around 1% of it is drinkable according to international standards due to various contaminations . Waste water discharge from industries, agricultural pollu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthopedic Implant
An orthopedic implant is a medical device manufactured to replace a missing joint or bone or to support a damaged bone. The medical implant is mainly fabricated using stainless steel and titanium alloys for strength and the plastic coating that is done on it acts as an artificial cartilage. Internal fixation is an operation in orthopedics that involves the surgical implementation of implants for the purpose of repairing a bone. During the surgery of broken bones through internal fixation the bone fragments are first reduced into their normal alignment then they are held together with the help of internal fixators such as plates, screws, nails, pins and wires. Eponymous implants and their uses * Austin-Moore prosthesis for fracture of the neck of femur * Baksi's prosthesis for elbow replacement * Charnley prosthesis for total hip replacement * Condylar blade plate for condylar fractures of femur * Ender's nail for fixing intertrochanteric fracture * Grosse-Kempf nail for tibial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Device
A medical device is any device intended to be used for medical purposes. Significant potential for hazards are inherent when using a device for medical purposes and thus medical devices must be proved safe and effective with reasonable assurance before regulating governments allow marketing of the device in their country. As a general rule, as the associated risk of the device increases the amount of testing required to establish safety and efficacy also increases. Further, as associated risk increases the potential benefit to the patient must also increase. Discovery of what would be considered a medical device by modern standards dates as far back as c. 7000 BC in Baluchistan where Neolithic dentists used flint-tipped drills and bowstrings. Study of archeology and Roman medical literature also indicate that many types of medical devices were in widespread use during the time of ancient Rome. In the United States it wasn't until the Federal Food, Drug, and Cosmetic Act (F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Implant (medicine)
An implant is a medical device manufactured to replace a missing biological structure, support a damaged biological structure, or enhance an existing biological structure. Medical implants are man-made devices, in contrast to a Organ transplant, transplant, which is a transplanted biomedical tissue. The surface of implants that contact the body might be made of a Biomaterial, biomedical material such as titanium, silicone, or apatite depending on what is the most functional. In some cases implants contain electronics, e.g. artificial pacemaker and cochlear implants. Some implants are Biological activity, bioactive, such as Subcutaneous tissue, subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents. Applications Implants can roughly be categorized into groups by application: Sensory and neurological Perception, Sensory and Neurotechnology#Implant technologies, neurological implants are used for disorders affecting the major senses and the br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3D Printed
3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model. It can be done in a variety of processes in which material is deposited, joined or solidified under computer control, with material being added together (such as plastics, liquids or powder grains being fused), typically layer by layer. In the 1980s, 3D printing techniques were considered suitable only for the production of functional or aesthetic prototypes, and a more appropriate term for it at the time was rapid prototyping. , the precision, repeatability, and material range of 3D printing have increased to the point that some 3D printing processes are considered viable as an industrial-production technology, whereby the term ''additive manufacturing'' can be used synonymously with ''3D printing''. One of the key advantages of 3D printing is the ability to produce very complex shapes or geometries that would be otherwise impossible to construct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthopedic Surgery
Orthopedic surgery or orthopedics ( alternatively spelt orthopaedics), is the branch of surgery concerned with conditions involving the musculoskeletal system. Orthopedic surgeons use both surgical and nonsurgical means to treat musculoskeletal trauma, spine diseases, sports injuries, degenerative diseases, infections, tumors, and congenital disorders. Etymology Nicholas Andry coined the word in French as ', derived from the Ancient Greek words ὀρθός ''orthos'' ("correct", "straight") and παιδίον ''paidion'' ("child"), and published ''Orthopedie'' (translated as ''Orthopædia: Or the Art of Correcting and Preventing Deformities in Children'') in 1741. The word was assimilated into English as ''orthopædics''; the ligature ''æ'' was common in that era for ''ae'' in Greek- and Latin-based words. As the name implies, the discipline was initially developed with attention to children, but the correction of spinal and bone deformities in all stages of life eventually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamellar Vector Field
In vector calculus, a complex lamellar vector field is a vector field which is orthogonal to a family of surfaces. In the broader context of differential geometry, complex lamellar vector fields are more often called hypersurface-orthogonal vector fields. They can be characterized in a number of different ways, many of which involve the curl. A lamellar vector field is a special case given by vector fields with zero curl. The adjective "lamellar" derives from the noun "lamella", which means a thin layer. The ''lamellae'' to which "lamellar vector field" refers are the surfaces of constant potential, or in the complex case, the surfaces orthogonal to the vector field. This language is particularly popular with authors in rational mechanics. Complex lamellar vector fields In vector calculus, a complex lamellar vector field is a vector field in three dimensions which is orthogonal to its own curl. That is, :\mathbf\cdot (\nabla\times \mathbf) = 0. The term lamellar vector field ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamellar Armour
Lamellar armour is a type of body armour, made from small rectangular plates (scales or ''lamellae'') of iron or steel, leather ( rawhide), or bronze laced into horizontal rows. Lamellar armour was used over a wide range of time periods in Central Asia, Eastern Asia (especially in China, Japan, Mongolia, and Tibet), Western Asia, and Eastern Europe. The earliest evidence for lamellar armour comes from sculpted artwork of the Neo-Assyrian Empire (911–609 BCE) in the Near East. Lamellar armour should not be confused with laminar armour, a related form of plate armour which is made from horizontal overlapping rows or bands of solid armour plates (called lames) rather than scales. By comparison, lamellar armour is made from individual armour scales, which are laced together to form a strip of armour which appears to be solid but is not. Description Lamellar armour consists of small platelets known as "lamellae" or "lames", which are punched and laced together, typically in horiz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agaric
An agaric () is a type of fungus fruiting body characterized by the presence of a pileus (cap) that is clearly differentiated from the stipe (stalk), with lamellae (gills) on the underside of the pileus. In the UK, agarics are called "mushrooms" or "toadstools". In North America they are typically called "gilled mushrooms". "Agaric" can also refer to a basidiomycete species characterized by an agaric-type fruiting body. Archaically, agaric meant 'tree-fungus' (after Latin ''agaricum''); however, that changed with the Linnaean interpretation in 1753 when Linnaeus used the generic name ''Agaricus'' for gilled mushrooms. Most species of agaricus belong to the order Agaricales in the subphylum Agaricomycotina. The exceptions, where agarics have evolved independently, feature largely in the orders Russulales, Boletales, Hymenochaetales, and several other groups of basidiomycetes. Old systems of classification placed all agarics in the Agaricales and some (mostly older) sources use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
