Carbon fiber in the context of "Polyacrylonitrile"

A surfboard is a narrow plank used in surfing. Surfboards are relatively light, but are strong enough to support an individual standing on them while riding an ocean wave. They were invented in ancient Hawaii (known as papa heʻe nalu in Hawaiian) and were usually made of wood from local trees, such as koa. They were often over 460 cm (15 ft) in length and extremely heavy. Major advances over the years include the addition of one or more fins (skegs) on the bottom rear of the board to improve directional stability, and numerous improvements in materials and shape.

Modern surfboards are made of polyurethane or polystyrene foam. Unlike soft top surfboards, hard top surfboards are also covered with layers of fiberglass cloth, polyester or epoxy resin. The result is a light and strong surfboard that is buoyant and maneuverable. Recent developments in surfboard technology have included the use of carbon fiber and kevlar composites, as well as experimentation in biodegradable and ecologically friendly resins made from organic sources. Each year, approximately 400,000 surfboards are manufactured.

Pole vaulting, also known as pole jumping, is a track and field event in which an athlete uses a long and flexible pole, usually made from fiberglass or carbon fiber, as an aid to jump over a bar. Pole jumping was already practiced by the ancient Egyptians, ancient Greeks and the ancient Irish people, although modern pole vaulting, an athletic contest where height is measured, was first established by the German teacher Johann Christoph Friedrich GutsMuths in the 1790s. It has been a full medal event at the Olympic Games since 1896 for men and since 2000 for women.

It is typically classified as one of the four major jumping events in athletics, alongside the high jump, long jump and triple jump. It is unusual among track and field events in that it requires a significant amount of specialised equipment in order to participate, even at a basic level. A number of elite pole vaulters have had backgrounds in gymnastics, including world record breakers Yelena Isinbayeva and Brian Sternberg, reflecting the similar physical attributes required for the events. Physical attributes such as speed, agility and strength, along with technical skill, are essential to pole vaulting.

Competitive cross-country skiing encompasses a variety of race formats and course lengths. Rules of cross-country skiing are sanctioned by the International Ski Federation and by various national organizations. International competitions include the FIS Nordic World Ski Championships, the FIS Cross-Country World Cup, and at the Winter Olympic Games. Such races occur over homologated, groomed courses designed to support classic (in-track) and freestyle events, where the skiers may employ skate skiing. It also encompasses cross-country ski marathon events, sanctioned by the Worldloppet Ski Federation, and cross-country ski orienteering events, sanctioned by the International Orienteering Federation. Related forms of competition are biathlon, where competitors race on cross-country skis and stop to shoot at targets with rifles, and paralympic cross-country skiing that allows athletes with disabilities to compete at cross-country skiing with adaptive equipment.

Norwegian army units were skiing for sport (and prizes) in the 18th century. Starting in the latter part of the 20th century, technique evolved from the striding in-track classic technique to include skate-skiing, which occurs on courses that have been groomed with wide lanes for those using the technique. At the same time, equipment evolved from skis and poles that were made of wood and other natural materials to comprising such man-made materials as fiberglass, carbon fiber, and polyethylene plastics.

Capillary action (sometimes called capillarity, capillary motion, capillary rise, capillary effect, or wicking) is the process of a liquid flowing in a narrow space without the assistance of external forces like gravity.

The effect can be seen in the drawing up of liquids between the hairs of a paint brush, in a thin tube such as a straw, in porous materials such as paper and plaster, in some non-porous materials such as clay and liquefied carbon fiber, or in biological cells.

Prestressed concrete is a form of concrete used in construction. It is substantially prestressed (compressed) during production, in a manner that strengthens it against tensile forces which will exist when in service. It was patented by Eugène Freyssinet in 1928.

This compression is produced by the tensioning of high-strength tendons located within or adjacent to the concrete and is done to improve the performance of the concrete in service. Tendons may consist of single wires, multi-wire strands or threaded bars that are most commonly made from high-tensile steels, carbon fiber or aramid fiber. The essence of prestressed concrete is that once the initial compression has been applied, the resulting material has the characteristics of high-strength concrete when subject to any subsequent compression forces and of ductile high-strength steel when subject to tension forces. This can result in improved structural capacity or serviceability, or both, compared with conventionally reinforced concrete in many situations. In a prestressed concrete member, the internal stresses are introduced in a planned manner so that the stresses resulting from the imposed loads are counteracted to the desired degree.

Amperometry in chemistry is the detection of ions in a solution based on electric current or changes in electric current.

Amperometry is used in electrophysiology to study vesicle release events using a carbon fiber electrode. Unlike patch clamp techniques, the electrode used for amperometry is not inserted into or attached to the cell but brought nearby of the cell. The measurements from the electrode originate from an oxidizing reaction of a vesicle cargo released into the medium. Another technique used to measure vesicle release is capacitive measurements.

A wood is a type of club used in the sport of golf. Woods have longer shafts and larger, rounder heads than other club types, and are used to hit the ball longer distances than other types.

Woods are so called because, traditionally, they had a club head that was made from hardwood, generally persimmon, but modern clubs have heads made from metal, for example titanium, or composite materials, such as carbon fiber. Some golf enthusiasts refer to these as "metals" or "metal woods" but this change in terminology is not strictly necessary, because while the material has changed, the style and intended use has not. The change to stronger materials has allowed the design of the modern woods to incorporate significantly larger heads than in the past. Because of the increase in club head size, in 2004, the USGA created a new stipulation for the size of the club head. The legal maximum volume displacement of any clubhead (by the rules of golf) is 460 cm (28.1 cu in)

A racing bicycle, also known as a road bike, is a bicycle designed for competitive road cycling, a sport governed by and according to the rules of the Union Cycliste Internationale (UCI).

Racing bicycles are designed for maximum performance while remaining legal under the UCI rules. They are designed to minimise aerodynamic drag, rolling resistance, and weight, and balance the desire for stiffness for pedaling effiency with the need for some flexibility for comfort. Racing bicycles sacrifice comfort for speed compared to non-racing bicycles. The drop handlebars are positioned lower than the saddle to put the rider in a more aerodynamic posture. The front and back wheels are close together so the bicycle has quick handling, which is preferred by experienced racing cyclists. The derailleur gear ratios are closely spaced so that the rider can pedal at their optimum cadence. However, racing bicycles must retain the ability to maneuver safely within a tightly-packed peloton, and be sufficiently comfortable to ride for races of six hours or more.