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Roller Skiing
Roller skiing is an off-snow equivalent to cross-country skiing. Roller skis have wheels on their ends and are used on a hard surface to emulate .Bryhn, Rolf and Knut Are Tvedt (eds.): ''Kunnskapsforlagets idrettsleksikon''. (Norwegian Encyclopedia of Sports). Oslo: Kunnskapsforlaget, 1990. The skiing techniques used are very similar to techniques used in cross-country skiing on snow. First created as a summer training exercise, roller skiing grew into a competitive sport in its own right. Annual championships are held in various locations around the world. Most, if not all, national cross-country ski teams around the world roller ski during the off-season for specific physical training simulating winter skiing. In Norway, separate roller ski facilities have been constructed to allow exercise off public roads. History The first roller skis were built in the mid-1930s in Italy and North Europe. In the early 1950s, when cross-country skiing started to evolve to a serious competitio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Kevlar
Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s as a replacement for steel in racing tires. It is typically spun into ropes or fabric sheets that can be used as such, or as an ingredient in composite material components. Kevlar has many applications, ranging from bicycle tires and sailcloth#Kevlar, racing sails to bulletproof vests, due to its high Specific strength, tensile strength-to-weight ratio; by this measure it is five times stronger than steel. It is also used to make modern marching drumheads that withstand high impact, and for Mooring, mooring lines and other underwater applications. A similar fiber, Twaron, with the same chemical structure was developed by Akzo in the 1970s. Commercial production started in 1986, and Twaron is manufactured by Teijin Aramid. History Poly- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Alaska
Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the northernmost, westernmost, and easternmost (the Aleutian Islands cross the 180th meridian into the eastern hemisphere) state in the United States. It borders the Canadian territory of Yukon and the province of British Columbia to the east. It shares a western maritime border, in the Bering Strait, with Russia's Chukotka Autonomous Okrug. The Chukchi and Beaufort Seas of the Arctic Ocean lie to the north, and the Pacific Ocean lies to the south. Technically, it is a semi-exclave of the U.S., and is the largest exclave in the world. Alaska is the largest U.S. state by area, comprising more total area than the following three largest states of Texas, California, and Montana combined, and is the seventh-largest subnational division i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Alberta
Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, the Northwest Territories to its north, and the U.S. state of Montana to its south. Alberta and Saskatchewan are the only two landlocked Canadian provinces. The eastern part of the province is occupied by the Great Plains, while the western part borders the Rocky Mountains. The province has a predominantly humid continental climate, continental climate, but seasonal temperatures tend to swing rapidly because it is so arid. Those swings are less pronounced in western Alberta because of its occasional Chinook winds. Alberta is the fourth largest province by area, at , and the fourth most populous, with 4,262,635 residents. Alberta's capital is Edmonton; its largest city is Calgary. The two cities are Alberta's largest Census geographic units ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ontario
Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it is home to 38.5% of the country's population, and is the second-largest province by total area (after Quebec). Ontario is Canada's fourth-largest jurisdiction in total area of all the Canadian provinces and territories. It is home to the nation's capital, Ottawa, and its list of the largest municipalities in Canada by population, most populous city, Toronto, which is Ontario's provincial capital. Ontario is bordered by the province of Manitoba to the west, Hudson Bay and James Bay to the north, and Quebec to the east and northeast. To the south, it is bordered by the U.S. states of (from west to east) Minnesota, Michigan, Ohio, Pennsylvania, and New York (state), New York. Almost all of Ontario's border with the United States follows riv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Helmet
A helmet is a form of protective gear worn to protect the head. More specifically, a helmet complements the skull in protecting the human brain. Ceremonial or symbolic helmets (e.g., a policeman's helmet in the United Kingdom) without protective function are sometimes worn. Soldiers wear combat helmets, often made from Kevlar or other lightweight synthetic fibers. The word ''helmet'' is derived from ''helm'', an Old English word for a protective head covering. Helmets are used for most sports (e.g., jockeys, American football, ice hockey, cricket, baseball, skiing, hurling and rock climbing); dangerous work activities such as construction, mining, riot police, military aviation, and in transportation (e.g. motorcycle helmets and bicycle helmets). Since the 1990s, most helmets are made from resin or plastic, which may be reinforced with fibers such as aramids. Designs Some British gamekeepers during the 18th and 19th centuries wore helmets made of straw bound together wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Glove
A glove is a garment covering the hand, with separate sheaths or openings for each finger including the thumb. Gloves protect and comfort hands against cold or heat, damage by friction, abrasion or chemicals, and disease; or in turn to provide a guard for what a bare hand should not touch. Gloves are made of materials including cloth, knitted or felted wool, leather, rubber, latex, neoprene, silk, and (in mail) metal. Gloves of kevlar protect the wearer from cuts. Gloves and gauntlets are integral components of pressure suits and spacesuits. Latex, nitrile rubber or vinyl disposable gloves are often worn by health care professionals as hygiene and contamination protection measures. Police officers often wear them to work in crime scenes to prevent destroying evidence in the scene. Many criminals wear gloves to avoid leaving fingerprints, which makes the crime investigation more difficult. However, the gloves themselves can leave prints that are just as unique as human fingerp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Tungsten Carbide
Tungsten carbide (chemical formula: ) is a carbide containing equal parts of tungsten and carbon atoms. In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes through sintering for use in industrial machinery, engineering facilities, molding blocks, cutting tools, chisels, abrasives, armor-piercing bullets and jewelry. Tungsten carbide is approximately three times as stiff as steel, with a Young's modulus of approximately 530–700 GPa, and is twice as dense as steel. It is comparable with corundum (α- ) in hardness, approaching that of a diamond, and can be polished and finished only with abrasives of superior hardness such as cubic boron nitride and diamond. Tungsten carbide tools can be operated at cutting speeds much higher than high-speed steel (a special steel blend for cutting tools). Tungsten carbide powder was first synthesized by H. Moissan in 1893, and the industrial production of the cemented form starte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ski Pole
Ski poles, also referred to as poles (in North America), sticks (UK), or stocks (Australia), are used by skiing, skiers for balance and propulsion. Modern ski poles are most commonly made from Aluminium, aluminum and Carbon fibers, carbon fiber, though materials such as bamboo are still used. Poles are used in alpine skiing, freestyle skiing (with the exception of aerials), and cross-country skiing. ski jumping, Ski jumpers do not use poles. History , the earliest ski pole was found in Sweden and dates back to 3623 BC, while the earliest depiction of a man with a ski pole was found in Norway in the form of a cave painting, dated at 4000 BC. Early skiers would use this pole for the purposes of balancing, braking, and turning. Alpine societies such as those in Nordic regions or the Altai mountains used their ski poles to hunt as well, giving them spear-like qualities. Skiers began to use two ski poles in 1741. This provided greater balance than one pole could provide and made pus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ski Boot
Ski boots are footwear used in skiing to provide a way to attach the skier to skis using ski bindings. The ski/boot/binding combination is used to effectively transmit control inputs from the skier's legs to the snow. History Ski boots were leather winter boots, held to the ski with leather straps. As skiing became more specialized, so too did ski boots, leading to the splitting of designs between those for alpine skiing and cross-country skiing (sport), cross-country skiing. Modern skiing developed as an all-round sport with uphill, downhill and cross-country portions. The introduction of the cable binding started a parallel evolution of binding and boot. The binding looped a strap around the back of the boot to hold it forward into a metal cup at the toe. Boots with the sole extended rearward to produce a flange for the cable to firmly latch to become common, as did designs with semi-circular indentations on the heel for the same purpose. Effective cross-country skiing require ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ski Binding
A ski binding is a device that connects a ski boot to the ski. Before the 1933 invention of Ski lift, ski lifts, skiers went uphill and down and cross-country on the same gear. As ski lifts became more prevalent, skis—and their bindings—became increasingly specialized, differentiated between Alpine skiing, alpine (downhill) and Nordic (Cross-country skiing, cross-country, Telemark skiing, Telemark, and ski jumping) styles of skiing. Until the point of divergence in the mid-20th century, bindings held the toe of a flexible, leather boot against the ski and allowed the heel to rise off the ski, typically with a form of strap or cable around the heel. To address injuries resulting from falls while skiing downhill on such equipment, ski bindings emerged with the ability to release the toe of the boot sideways, in early models, and to release the boot forward and aft, in later models. Downhill ski bindings became standardized to fit plastic ski boots and incorporated a built-in bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Skike
A skike is a sports device consisting of two wheels attached to a frame that can be strapped onto the rider's shoe. Similarly to roller skis, the skike has a wheel in front and at the tail of an aluminium Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ... frame that can be attached to the foot. However, unlike roller skis and roller skates the tires are pneumatic. In addition to asphalt, the skikes can therefore be used on rougher terrain such as dirt roads, plaster and gravel. The skike straps onto the rider's shoe, and does not require any special type of boot. It has a brake on the heel that allows the rider to stop or brake gradually by pushing back the lower legs. The name skike is a combination of ''skate'' and ''bike''. The skike rider moves forward in a skating motion, us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
