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Basketball (ball)
A basketball is a Sphere, spherical ball used in basketball games. Basketballs usually range in size from very small promotional items that are only a few inches (some centimeters) in diameter to extra large balls nearly in diameter used in training exercises. For example, a youth basketball could be in circumference, while a National Collegiate Athletic Association (NCAA) men's ball would be a maximum of and an NCAA women's ball would be a maximum of . The standard for a basketball in the National Basketball Association (NBA) is in circumference and for the Women's National Basketball Association (WNBA), a maximum circumference of . High school and junior leagues normally use NCAA, NBA or WNBA sized balls. Aside from the court and the baskets, the basketball is the only piece of equipment necessary to play the game of basketball. During the game, the ball must be bounced continuously (Basketball#Dribbling, dribbling), thrown through the air to other players (Basketball#Passi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basketball
Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular Basketball court, court, compete with the primary objective of #Shooting, shooting a basketball (ball), basketball (approximately in diameter) through the defender's Basket (basketball), hoop (a basket in diameter mounted high to a Backboard (basketball), backboard at each end of the court), while preventing the opposing team from shooting through their own hoop. A Field goal (basketball), field goal is worth two points, unless made from behind the 3 point line, three-point line, when it is worth three. After a foul, timed play stops and the player fouled or designated to shoot a technical foul is given one, two or three one-point free throws. The team with the most points at the end of the game wins, but if regulation play expires with the score tied, an additional period of play (Overtime (sports), overtime) is mandated. Players advance the ball by boun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three Point Contest
The Three-Point Contest is a National Basketball Association (NBA) contest held on the Saturday before the annual All-Star Game as part of All-Star weekend. The 2019 iteration of the contest involved ten participants. From its introduction in 1986 to 2018, eight participants were selected to participate in each season's shootout. In 2002–2003 to 2012-2013 there were six participants. Tyler Herro of the Miami Heat is the most recent winner of the event, which was held at Chase Center in San Francisco. Buddy Hield also tied Steph Curry’s record of 31 points in the latest edition of the three-point contest. Rules In this contest, participants attempt to make as many three-point field goals as possible from five positions behind the three-point line in one minute. Players begin shooting from one corner of the court, and move from station to station along the three-point arc until they reach the other corner. At each shooting station is a rack with five basketballs. Out of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amer Sports
Amer Sports, Inc. is a Finnish multinational sporting equipment company based in Helsinki, Finland. Established in 1950 as an industrial conglomerate with interests as diverse as tobacco trading, ship owning and publishing, Amer has gradually evolved into a multinational firm devoted to the production and marketing of sporting goods. The company employs over 9,700 people. Amer Sports owns a portfolio of companies, including Atomic, Arc'teryx, Armada, Enve Composites, Peak Performance, Salomon, and Wilson, among others. Amer is itself owned by Chinese retail conglomerate Anta Sports. History Industrial past (1950–1985) The company began life as a tobacco manufacturer and distributor, Amer-Tupakka, in 1950 (later to be renamed Amer-Yhtymä Oyj followed by its current designation) and acquired the right to produce and sell Philip Morris cigarettes in Finland in 1961. In the 1960s, the significant profits from the company's tobacco interests were invested in three comme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3x3 Basketball
3x3 basketball (stylized as ''ƐX3'', pronounced ''three-ex-three'') is a Variations of basketball, variation of basketball played three-a-side, with one Backboard (basketball), backboard and in a basketball court, half-court setup. This basketball game format is currently being promoted and structured by FIBA, the sport's governing body. Its primary competition is an annual FIBA 3x3 World Tour, FIBA 3X3 World Tour, comprising a series of Masters and one Final tournament, and awarding six-figure prize money in United States dollar, US dollars. The FIBA 3x3 World Cups for men and women are the highest tournaments for national 3x3 teams. The 3x3 format has been adopted for both the 2020 Summer Olympics and 2022 Commonwealth Games. History 3x3 has been a basketball format long played in streets and gyms across the world, albeit in a less formal way. Starting in the late 2000s, 3x3 game rules started to become standardized throughout the United States, most notably through the Gus Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collagen
Collagen () is the main structural protein in the extracellular matrix of the connective tissues of many animals. It is the most abundant protein in mammals, making up 25% to 35% of protein content. Amino acids are bound together to form a triple helix of elongated fibril known as a collagen helix. It is mostly found in cartilage, bones, tendons, ligaments, and skin. Vitamin C is vital for collagen synthesis. Depending on the degree of biomineralization, mineralization, collagen tissues may be rigid (bone) or compliant (tendon) or have a gradient from rigid to compliant (cartilage). Collagen is also abundant in corneas, blood vessels, the Gut (anatomy), gut, intervertebral discs, and the dentin in teeth. In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes 1% to 2% of muscle tissue and 6% by weight of skeletal muscle. The fibroblast is the most common cell creating collagen in animals. Gelatin, which is used in food and industry, is collagen t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexamethylenediamine
Hexamethylenediamine or hexane-1,6-diamine, is the organic compound with the formula H2N(CH2)6NH2. The molecule is a diamine, consisting of a hexamethylene hydrocarbon chain terminated with amine functional groups. The colorless solid (yellowish for some commercial samples) has a strong amine odor. Synthesis Hexamethylenediamine was first reported by Theodor Curtius. It is produced by the hydrogenation of adiponitrile: :NC(CH2)4CN + 4 H2 → H2N(CH2)6NH2 The hydrogenation is conducted on molten adiponitrile diluted with ammonia, typical catalysts being based on cobalt and iron. The yield is good, but commercially significant side products are generated by virtue of reactivity of partially hydrogenated intermediates. These other products include 1,2-diaminocyclohexane, hexamethyleneimine, and the triamine bis(hexamethylenetriamine). An alternative process uses Raney nickel as the catalyst and adiponitrile that is diluted with hexamethylenediamine itself (as the solvent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adipic Acid
Adipic acid or hexanedioic acid is the organic compound with the formula C6H10O4. It a white crystalline powder at standard temperature and pressure. From an industrial perspective, it is the most important dicarboxylic acid at about 2.5 billion kilograms produced annually, mainly as a precursor for the production of nylon. Adipic acid otherwise rarely occurs in nature, but it is known as manufactured E number food additive E355. Salts and esters of adipic acid are known as adipates. Preparation and reactivity Adipic acid is produced by oxidation of a mixture of cyclohexanone and cyclohexanol, which is called KA oil, an abbreviation of ketone-alcohol oil. Nitric acid is the oxidant. The pathway is multistep. Early in the reaction, the cyclohexanol is converted to the ketone, releasing nitrous acid: : The cyclohexanone is then nitrosated, setting the stage for the scission of the C-C bond: : : Side products of the method include glutaric and succinic acids. Nitrous oxide is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amide Groups
In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a compound with the general formula , where R, R', and R″ represent any group, typically organyl groups or hydrogen atoms. The amide group is called a peptide bond when it is part of the main chain of a protein, and an isopeptide bond when it occurs in a side chain, as in asparagine and glutamine. It can be viewed as a derivative of a carboxylic acid () with the hydroxyl group () replaced by an amino group (); or, equivalently, an acyl (alkanoyl) group () joined to an amino group. Common amides are formamide (), acetamide (), benzamide (), and dimethylformamide (). Some uncommon examples of amides are ''N''-chloroacetamide () and chloroformamide (). Amides are qualified as primary, secondary, and tertiary according to the number of acyl groups bounded to the nitrogen atom. Nomenclature The core of amides is called the amide group (specifically, carboxamide group). In the usual nome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyamide
A polyamide is a polymer with repeating units linked by amide bonds. Polyamides occur both naturally and artificially. Examples of naturally occurring polyamides are proteins, such as wool and silk. Artificially made polyamides can be made through step-growth polymerization or solid-phase synthesis yielding materials such as nylons, aramids, and sodium polyaspartate. Synthetic polyamides are commonly used in textiles, automotive industry, carpets, kitchen utensils and sportswear due to their high durability and strength. The transportation manufacturing industry is the major consumer, accounting for 35% of polyamide (PA) consumption. Classification Polymers of amino acids are known as polypeptides or proteins. According to the composition of their main chain, synthetic polyamides are classified as follows: All polyamides are made by the formation of an amide function to link two molecules of monomer together. The monomers can be amides themselves (usually in the form of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscous
Viscosity is a measure of a fluid's rate-dependent resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for example, syrup has a higher viscosity than water. Viscosity is defined scientifically as a force multiplied by a time divided by an area. Thus its SI units are newton-seconds per metre squared, or pascal-seconds. Viscosity quantifies the internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's center line than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the streng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoprene
Isoprene, or 2-methyl-1,3-butadiene, is a common volatile organic compound with the formula CH2=C(CH3)−CH=CH2. In its pure form it is a colorless volatile liquid. It is produced by many plants and animals (including humans) and its polymers are the main component of natural rubber. History and etymology Charles Greville Williams, C. G. Williams named the compound in 1860 after obtaining it from the pyrolysis of natural rubber. He correctly deduced the mass shares of carbon and hydrogen (but arrived at an incorrect formula C10H8 because the modern atomic weight of carbon was not adopted until the Karlsruhe Congress held later that year). He did not specify the reasons for the name, but it is hypothesized that it came from "propylene" with which isoprene shares some physical and chemical properties. The first one to observe recombination of isoprene into rubber-like substance was in 1879, and William A. Tilden identified its structure five years later. Natural occurrences Is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
