Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus Gossypium in the family of Malvaceae. The fiber is almost pure cellulose, under natural conditions, the cotton bolls will tend to increase the dispersal of the seeds. The plant is a native to tropical and subtropical regions around the world, including the Americas, Africa. The greatest diversity of wild species is found in Mexico, followed by Australia. Cotton was independently domesticated in the Old and New Worlds, the fiber is most often spun into yarn or thread and used to make a soft, breathable textile. Current estimates for world production are about 25 million tonnes or 110 million bales annually, China is the worlds largest producer of cotton, but most of this is used domestically. The United States has been the largest exporter for many years, in the United States, cotton is usually measured in bales, which measure approximately 0.48 cubic meters and weigh 226.8 kilograms.
Cotton cultivation in the region is dated to the Indus Valley Civilization, the Indus cotton industry was well-developed and some methods used in cotton spinning and fabrication continued to be used until the industrialization of India. Between 2000 and 1000 BC cotton became widespread across much of India, for example, it has been found at the site of Hallus in Karnataka dating from around 1000 BC. Cotton fabrics discovered in a cave near Tehuacán, Mexico have been dated to around 5800 BC, the domestication of Gossypium hirsutum in Mexico is dated between 3400 and 2300 BC. Cotton was grown upriver, made into nets, and traded with fishing villages along the coast for supplies of fish. The Spanish who came to Mexico and Peru in the early 16th century found the people growing cotton and this may be a reference to tree cotton, Gossypium arboreum, which is a native of the Indian subcontinent. According to the Columbia Encyclopedia, Cotton has been spun, woven and it clothed the people of ancient India and China.
Hundreds of years before the Christian era, cotton textiles were woven in India with matchless skill, in Iran, the history of cotton dates back to the Achaemenid era, there are few sources about the planting of cotton in pre-Islamic Iran. The planting of cotton was common in Merv and Pars of Iran, in Persian poets poems, especially Ferdowsis Shahname, there are references to cotton. Marco Polo refers to the products of Persia, including cotton. John Chardin, a French traveler of the 17th century who visited the Safavid Persia, during the Han dynasty, cotton was grown by Chinese peoples in the southern Chinese province of Yunnan. Mohamed Ali Pasha accepted the proposition and granted himself the monopoly on the sale and export of cotton in Egypt, and dictated cotton should be grown in preference to other crops
Bookbinding is the process of physically assembling a book from an ordered stack of paper sheets that are folded together into sections or sometimes left as a stack of individual sheets. The stack is bound together along one edge by either sewing with thread through the folds or by a layer of flexible adhesive, for protection, the bound stack is either wrapped in a flexible cover or attached to stiff boards. Finally, a cover is adhered to the boards and a label with identifying information is attached to the covers along with additional decoration. Bookbinding is a trade that relies on basic operations of measuring, cutting. A finished book depends on a minimum of two dozen operations to complete but sometimes more than double that according to the specific style. All operations have an order and each one relies on accurate completion of the previous step with little room for back tracking. An extremely durable binding can be achieved by using the best hand techniques, Bookbinding combines skills from other trades such as paper and fabric crafts, leather work, model making, and graphic arts.
It requires knowledge about numerous varieties of book structures along with all the internal and external details of assembly, a working knowledge of the materials involved is required. Bookbinding is a craft of great antiquity, and at the same time. The division between craft and industry is not so wide as might at first be imagined and it is interesting to observe that the main problems faced by the mass-production bookbinder are the same as those that confronted the medieval craftsman or the modern hand binder. Before the computer age, the bookbinding trade involved two divisions, second was Letterpress binding which deals with making new books intended to be read from and includes fine binding, library binding, edition binding, and publishers bindings. A result of the new bindings is a third division dealing with the repair, with the digital age, personal computers have replaced the pen and paper based accounting that used to drive most of the work in the stationery binding industry.
There is a grey area between the two divisions. There are cases where the printing and binding jobs are combined in one shop, a step up to the next level of mechanization is determined by economics of scale until you reach production runs of ten thousand copies or more in a factory employing a dozen or more workers. The craft of bookbinding probably originated in India, where religious sutras were copied on to palm leaves with a metal stylus, the leaf was dried and rubbed with ink, which would form a stain in the wound. The finished leaves were given numbers, and two long twines were threaded through each end through wooden boards, making a palm-leaf book, when the book was closed, the excess twine would be wrapped around the boards to protect the manuscript leaves. Buddhist monks took the idea through Afghanistan to China in the first century BC, similar techniques can be found in ancient Egypt where priestly texts were compiled on scrolls and books of papyrus. Another version of bookmaking can be seen through the ancient Mayan codex, writers in the Hellenistic-Roman culture wrote longer texts as scrolls, these were stored in boxes or shelving with small cubbyholes, similar to a modern winerack
The performers may communicate this experience to the audience through combinations of gesture, song and dance. Elements of art, such as painted scenery and stagecraft such as lighting are used to enhance the physicality, the specific place of the performance is named by the word theatre as derived from the Ancient Greek θέατρον, itself from θεάομαι. Modern theatre, broadly defined, includes performances of plays and musical theatre, there are connections between theatre and the art forms of ballet and various other forms. The city-state of Athens is where western theatre originated, participation in the city-states many festivals—and mandatory attendance at the City Dionysia as an audience member in particular—was an important part of citizenship. The Greeks developed the concepts of dramatic criticism and theatre architecture, Actors were either amateur or at best semi-professional. The theatre of ancient Greece consisted of three types of drama, tragedy and the satyr play, the origins of theatre in ancient Greece, according to Aristotle, the first theoretician of theatre, are to be found in the festivals that honoured Dionysus.
The performances were given in semi-circular auditoria cut into hillsides, capable of seating 10, the stage consisted of a dancing floor, dressing room and scene-building area. Since the words were the most important part, good acoustics, the actors wore masks appropriate to the characters they represented, and each might play several parts. Athenian tragedy—the oldest surviving form of tragedy—is a type of dance-drama that formed an important part of the culture of the city-state. Having emerged sometime during the 6th century BCE, it flowered during the 5th century BCE, no tragedies from the 6th century BCE and only 32 of the more than a thousand that were performed in during the 5th century BCE have survived. We have complete texts extant by Aeschylus and Euripides, the origins of tragedy remain obscure, though by the 5th century BCE it was institution alised in competitions held as part of festivities celebrating Dionysus. As contestants in the City Dionysias competition playwrights were required to present a tetralogy of plays, the performance of tragedies at the City Dionysia may have begun as early as 534 BCE, official records begin from 501 BCE, when the satyr play was introduced.
More than 130 years later, the philosopher Aristotle analysed 5th-century Athenian tragedy in the oldest surviving work of dramatic theory—his Poetics, Athenian comedy is conventionally divided into three periods, Old Comedy, Middle Comedy, and New Comedy. Old Comedy survives today largely in the form of the surviving plays of Aristophanes. New Comedy is known primarily from the papyrus fragments of Menander. Aristotle defined comedy as a representation of people that involves some kind of blunder or ugliness that does not cause pain or disaster. In addition to the categories of comedy and tragedy at the City Dionysia, finding its origins in rural, agricultural rituals dedicated to Dionysus, the satyr play eventually found its way to Athens in its most well-known form. Satyrs themselves were tied to the god Dionysus as his loyal companions, often engaging in drunken revelry
Carpentry in the United States is almost always done by men. With 98. 5% of carpenters being male, it was the fourth most male-dominated occupation in the country in 1999, Carpenters are usually the first tradesmen on a job and the last to leave. Carpenters normally framed post-and-beam buildings until the end of the 19th century and it is common that the skill can be learned by gaining work experience other than a formal training program, which may be the case in many places. The word carpenter is the English rendering of the Old French word carpentier which is derived from the Latin carpentrius, the Middle English and Scots word was wright, which could be used in compound forms such as wheelwright or boatwright. An easy way to envisage this is that first fix work is all that is done before plastering takes place, second fix is done after plastering takes place. Second fix work, the construction of such as skirting boards, architraves. Carpentry is used to construct the formwork into which concrete is poured during the building of such as roads.
In the UK, the skill of making timber formwork for poured, or in situ, although the. work of a carpenter and joiner are often combined. Joiner is less common than the finish carpenter or cabinetmaker. The terms housewright and barnwright were used historically, now used by carpenters who work using traditional methods. Someone who builds custom concrete formwork is a form carpenter, wood is one of mankinds oldest building materials. The ability to shape wood improved with technological advances from the age to the bronze age to the iron age. The oldest surviving, complete text is Vitruvius ten books collectively titled De architectura which discusses some carpentry. By the 16th century sawmills were coming into use in Europe, the founding of America was partly based on a desire to extract resources from the new continent including wood for use in ships and buildings in Europe. In the 18th century part of the Industrial Revolution was the invention of the steam engine and these technologies combined with the invention of the circular saw led to the development of balloon framing which was the beginning of the decline of traditional timber framing.
The 19th century saw the development of engineering and distribution which allowed the development of hand-held power tools, wire nails. In the 20th century portland cement came into use and concrete foundations allowed carpenters to do away with heavy timber sills. Also, drywall came into common use replacing lime plaster on wooden lath, engineered lumber and chemically treated lumber came into use
A linear actuator is an actuator that creates motion in a straight line, in contrast to the circular motion of a conventional electric motor. Hydraulic or pneumatic cylinders inherently produce linear motion, many other mechanisms are used to generate linear motion from a rotating motor. Mechanical linear actuators typically operate by conversion of rotary motion into linear motion, by rotating the actuators nut, the screw shaft moves in a line. Wheel and axle, winch and pinion, chain drive, belt drive, rigid chain and rigid belt actuators operate on the principle of the wheel, a rotating wheel moves a cable, chain or belt to produce linear motion. Cam, Cam actuators function on a similar to that of the wedge. As a wheel-like cam rotates, its eccentric shape provides thrust at the base of a shaft, some mechanical linear actuators only pull, such as hoists, chain drive and belt drives. Pneumatic and hydraulic cylinders, or lead screws can be designed to force in both directions. Mechanical actuators typically convert rotary motion of a knob or handle into linear displacement via screws and/or gears to which the knob or handle is attached. A jackscrew or car jack is a mechanical actuator.
Another family of actuators are based on the segmented spindle, rotation of the jack handle is converted mechanically into the linear motion of the jack head. For accurate and repeatable positioning, index marks may be used on control knobs, some actuators include an encoder and digital position readout. These are similar to the adjustment knobs used on micrometers except their purpose is position adjustment rather than position measurement, hydraulic actuators or hydraulic cylinders typically involve a hollow cylinder having a piston inserted in it. An unbalanced pressure applied to the piston generates force that can move an external object, since liquids are nearly incompressible, a hydraulic cylinder can provide controlled precise linear displacement of the piston. The displacement is only along the axis of the piston, a familiar example of a manually operated hydraulic actuator is a hydraulic car jack. Typically though, the hydraulic actuator refers to a device controlled by a hydraulic pump.
Pneumatic actuators, or pneumatic cylinders, are similar to hydraulic actuators except they use compressed gas to generate force instead of a liquid and they work similarly to a piston in which air is pumped inside a chamber and pushed out of the other side of the chamber. Air actuators are not necessarily used for heavy duty machinery and instances where large amounts of weight are present, one of the reasons pneumatic linear actuators are preferred to other types is the fact that the power source is simply an air compressor. Because air is the source, pneumatic actuators are able to be used in many places of mechanical activity
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom or Britain, is a sovereign country in western Europe. Lying off the north-western coast of the European mainland, the United Kingdom includes the island of Great Britain, Northern Ireland is the only part of the United Kingdom that shares a land border with another sovereign state—the Republic of Ireland. The Irish Sea lies between Great Britain and Ireland, with an area of 242,500 square kilometres, the United Kingdom is the 78th-largest sovereign state in the world and the 11th-largest in Europe. It is the 21st-most populous country, with an estimated 65.1 million inhabitants, this makes it the fourth-most densely populated country in the European Union. The United Kingdom is a monarchy with a parliamentary system of governance. The monarch is Queen Elizabeth II, who has reigned since 6 February 1952, other major urban areas in the United Kingdom include the regions of Birmingham, Glasgow and Manchester.
The United Kingdom consists of four countries—England, Wales, the last three have devolved administrations, each with varying powers, based in their capitals, Edinburgh and Belfast, respectively. The relationships among the countries of the UK have changed over time, Wales was annexed by the Kingdom of England under the Laws in Wales Acts 1535 and 1542. A treaty between England and Scotland resulted in 1707 in a unified Kingdom of Great Britain, which merged in 1801 with the Kingdom of Ireland to form the United Kingdom of Great Britain and Ireland. Five-sixths of Ireland seceded from the UK in 1922, leaving the present formulation of the United Kingdom of Great Britain, there are fourteen British Overseas Territories. These are the remnants of the British Empire which, at its height in the 1920s, British influence can be observed in the language and legal systems of many of its former colonies. The United Kingdom is a country and has the worlds fifth-largest economy by nominal GDP. The UK is considered to have an economy and is categorised as very high in the Human Development Index.
It was the worlds first industrialised country and the worlds foremost power during the 19th, the UK remains a great power with considerable economic, military and political influence internationally. It is a nuclear weapons state and its military expenditure ranks fourth or fifth in the world. The UK has been a permanent member of the United Nations Security Council since its first session in 1946 and it has been a leading member state of the EU and its predecessor, the European Economic Community, since 1973. However, on 23 June 2016, a referendum on the UKs membership of the EU resulted in a decision to leave. The Acts of Union 1800 united the Kingdom of Great Britain, Scotland and Northern Ireland have devolved self-government
World War II
World War II, known as the Second World War, was a global war that lasted from 1939 to 1945, although related conflicts began earlier. It involved the vast majority of the worlds countries—including all of the great powers—eventually forming two opposing alliances, the Allies and the Axis. It was the most widespread war in history, and directly involved more than 100 million people from over 30 countries. Marked by mass deaths of civilians, including the Holocaust and the bombing of industrial and population centres. These made World War II the deadliest conflict in human history, from late 1939 to early 1941, in a series of campaigns and treaties, Germany conquered or controlled much of continental Europe, and formed the Axis alliance with Italy and Japan. Under the Molotov–Ribbentrop Pact of August 1939, Germany and the Soviet Union partitioned and annexed territories of their European neighbours, Finland and the Baltic states. In December 1941, Japan attacked the United States and European colonies in the Pacific Ocean, and quickly conquered much of the Western Pacific.
The Axis advance halted in 1942 when Japan lost the critical Battle of Midway, near Hawaii, in 1944, the Western Allies invaded German-occupied France, while the Soviet Union regained all of its territorial losses and invaded Germany and its allies. During 1944 and 1945 the Japanese suffered major reverses in mainland Asia in South Central China and Burma, while the Allies crippled the Japanese Navy, thus ended the war in Asia, cementing the total victory of the Allies. World War II altered the political alignment and social structure of the world, the United Nations was established to foster international co-operation and prevent future conflicts. The victorious great powers—the United States, the Soviet Union, the United Kingdom, the Soviet Union and the United States emerged as rival superpowers, setting the stage for the Cold War, which lasted for the next 46 years. Meanwhile, the influence of European great powers waned, while the decolonisation of Asia, most countries whose industries had been damaged moved towards economic recovery.
Political integration, especially in Europe, emerged as an effort to end pre-war enmities, the start of the war in Europe is generally held to be 1 September 1939, beginning with the German invasion of Poland and France declared war on Germany two days later. The dates for the beginning of war in the Pacific include the start of the Second Sino-Japanese War on 7 July 1937, or even the Japanese invasion of Manchuria on 19 September 1931. Others follow the British historian A. J. P. Taylor, who held that the Sino-Japanese War and war in Europe and its colonies occurred simultaneously and this article uses the conventional dating. Other starting dates sometimes used for World War II include the Italian invasion of Abyssinia on 3 October 1935. The British historian Antony Beevor views the beginning of World War II as the Battles of Khalkhin Gol fought between Japan and the forces of Mongolia and the Soviet Union from May to September 1939, the exact date of the wars end is not universally agreed upon.
It was generally accepted at the time that the war ended with the armistice of 14 August 1945, rather than the formal surrender of Japan
Li Ning is a retired Chinese gymnast and entrepreneur. He founded the sportswear company Li-Ning, Li started training at the age of eight and was selected into the national team in 1980. In 1982, he won six of the seven medals awarded at the Sixth World Cup Gymnastic Competition, Li is most famous for winning 6 medals at the 1984 Summer Olympics, which was the first Olympics in which the Peoples Republic of China participated. He won three medals, two silver medals, and one bronze medal. Li became the most decorated Chinese athlete at the first Olympics that China participated in after the founding of the Peoples Republic in October 1949, Li won 11 World Artistic Gymnastics Championships medals, including gold medals in the rings and team all-around. Li took part in his second 1988 Olympics in Seoul despite carrying injuries and it was an end to an illustrious gymnastic career, as he was off-form and made crucial mistakes which robbed him of the chance of a medal. Li retired from sporting competition in 1988, and in 1990 he founded Li-Ning Company Limited, Li remains chairman of the companys board of directors.
According to Hurun Reports China Rich List 2014, he has a fortune of RMB5 billion. Li was inducted into the International Gymnastics Hall of Fame in 2000, at the 2008 Summer Olympics Li Ning ignited the cauldron at the opening ceremony after being hoisted high into the air with cables and miming running around the rim of the stadium. Li is married to Chen Yongyan, a fellow gymnast who won an Olympic bronze in 1984
Batiste is a fine cloth made from cotton, polyester, or a blend, and the softest of the lightweight opaque fabrics. Batiste is a plain weave, a fine cloth made from cotton or linen such as cambric. Batiste was often used as a fabric for high-quality garments. Batiste is used for handkerchiefs and lingerie, in 1901 Chamberss Twentieth Century Dictionary of the English Language defined batiste as usual French name for cambric or applied in commerce to a fine texture of linen and cotton. Cambric is a synonym of the French word batiste, itself attested since 1590, Batiste itself comes from the Picard batiche, attested since 1401, derived from the old French battre for bowing wool. Lightweight opaque fabrics are very thin and light but not as transparent as sheer fabrics, the distinction between the two is not always pronounced. End uses include apparel and furnishings, organdy and batiste begin as the same greige goods. They differ from one another in the way they are finished and batiste do not receive the acid finish and, remain opaque.
Better quality fabrics are made of combed yarns, cambric Media related to Batiste at Wikimedia Commons
A curtain is a piece of cloth intended to block or obscure light, or drafts, or water in the case of a shower curtain. A curtain is the screen or drape in a theater that separates the stage from the auditorium or that serves as a backdrop. Curtains hung over a doorway are known as portières, Curtains are often hung on the inside of a buildings windows to block the passage of light, for instance at night to aid sleeping, or to stop light from escaping outside the building. In this application, they are known as draperies. Curtains vary according to cleanability, ultraviolet light deterioration and dust retention, noise absorption, fire resistance, Curtains may be moved by hand, with cords, by press-button pads or remote-controlled computers. They are held out of the way of the window by means of curtain tie-backs, measuring curtain sizes needed for each window varies greatly according to the type of curtain needed, window size, and type and weight of curtain. Curtains are a form of treatment, and complete the overall appearance of the house.
Window treatment helps control the ambiance and flow of light into the room. The effect of drapery or curtains is best seen in daylight, from evidence found in excavation sites at Olynthus and Herculaneum, portieres appear to have been used as room dividers in classic antiquity. Mosaics from the 2nd to 6th century show curtains suspended from rods spanning arches, Curtains are manufactured from a variety of thick fabrics, each with a differing degree of light absorption and heat insulating qualities. For maximum temperature control, the gap to the window should be small. Various architectural structures around the curtain can minimize these air drafts, a sheer or net curtain is one that is made from translucent fabric, such as a loosely woven polyester voile or a cotton lace. Due to the weave in sheer fabrics, these types of curtains offer very little in the way of heat insulation. Uncoated fabrics provide the level of heat insulation and light absorption. Uncoated fabrics provide a level of heat insulation due to the tight weave of the fabric.
However, the fabric itself is not thick enough to completely absorb strong light sources. As a result, when made from uncoated fabrics are closed in an attempt to block out direct sunlight, light will still be visible through the curtain. Coated fabrics consist of a standard uncoated fabric with an opaque rubber backing applied to the rear of the fabric to provide improved light absorption
Broadcloth is a dense, plain woven cloth, historically made of wool. The defining characteristic of Broadcloth is not its finished width, but the fact that it was much wider. The effect of the process is to draw the yarns much closer together than could be achieved in the loom. This results in a dense, blind face cloth with a stiff drape which is highly weather-resistant, hard wearing and it was made in several parts of England at the end of the medieval period. The raw material was short staple wool and spun into yarn and it was fulled, usually in a fulling mill. When fulled, the fibres of the cloth would felt together, Broadcloth was first produced in Flanders from the 11th century and throughout the medieval period. After 1400 Leiden in Holland became the most important place for industry in Europe. There for the first time the production became industrialised and this means that the production process didnt take place entirely in one single factory anymore but according to a precise task allocation, where in several stages intermediate goods were produced.
The entire process was supervised, resulting in a constantly high quality. In 1417 the Hanseatic League decided that only approved broadcloth from Leiden was to be sold, from 1500 competition from other parts of Europe, especially England and Leiden lost its leading role. In Italy Florence was an important center of broadcloth industry and this was the best English cloth, and large quantities were exported by the merchants of the Company of Merchant Adventurers of London, principally to Antwerp as white cloth. It was finished and dyed in Flanders, and marketed throughout northern Europe, the cloths might be short or long. The raw material for broadcloth from Worcester was wool from the Welsh border counties of Herefordshire and Shropshire and that for the West Country came from the Cotswolds. In both cases, the quality was the result of the comparatively poor pasture, which led the sheep to grow wool with the desired qualities. English exports of broadcloth reached their highest level in the mid 16th century, difficulties were encountered in export markets in the mid-1610s, partly due to currency difficulties in eastern Europe, and partly to the ill-conceived Cockayne Project.
Broadcloth production thus declined in the 17th century, Worcester remained a centre for the production of white broadcloth. Other areas, such as Ludlow and parts of the Cotswolds started to produce similar cloth, the market suffered major setback in the 18th century, when the trade of the Levant Company with Turkey was obstructed by French competition. From this time, the production of broadcloth finally lost its importance, banat Wool broadcloth made in India
Carbon fiber reinforced polymer
Carbon fiber reinforced polymer, carbon fiber reinforced plastic or carbon fiber reinforced thermoplastic, is an extremely strong and light fiber-reinforced plastic which contains carbon fibers. The spelling fibre is common in British Commonwealth countries, the binding polymer is often a thermoset resin such as epoxy, but other thermoset or thermoplastic polymers, such as polyester, vinyl ester or nylon, are sometimes used. The composite may contain other fibers, such as an aramid, ultra-high-molecular-weight polyethylene or glass fibers, the properties of the final CFRP product can be affected by the type of additives introduced to the binding matrix. The most frequent additive is silica, but other such as rubber. The material is referred to as graphite-reinforced polymer or graphite fiber-reinforced polymer. In product advertisements, it is referred to simply as graphite fiber for short. In this case the composite consists of two parts, a matrix and a reinforcement, in CFRP the reinforcement is carbon fiber, which provides the strength.
The matrix is usually a resin, such as epoxy. Because CFRP consists of two elements, the material properties depend on these two elements. The reinforcement will give the CFRP its strength and rigidity, measured by stress, unlike isotropic materials like steel and aluminum, CFRP has directional strength properties. The properties of CFRP depend on the layouts of the carbon fiber, the following equation, E c = V m E m + V f E f is valid for composite materials with the fibers oriented in the direction of the applied load. Typical epoxy-based CFRPs exhibit virtually no plasticity, with less than 0. 5% strain to failure, although CFRPs with epoxy have high strength and elastic modulus, the brittle fracture mechanics present unique challenges to engineers in failure detection since failure occurs catastrophically. As such, recent efforts to toughen CFRPs include modifying the existing epoxy material, One such material with high promise is PEEK, which exhibits an order of magnitude greater toughness with similar elastic modulus and tensile strength.
However, PEEK is much more difficult to process and more expensive, despite its high initial strength-to-weight ratio, a design limitation of CFRP is its lack of a definable fatigue endurance limit. This means, that stress cycle failure cannot be ruled out, environmental effects such as temperature and humidity can have profound effects on the polymer-based composites, including most CFRPs. While the carbon fibers themselves are not affected by the moisture diffusing into the material, the carbon fibers can cause galvanic corrosion when CRP parts are attached to aluminum. The primary element of CFRP is a filament, this is produced from a precursor polymer such as polyacrylonitrile, rayon. Precursor compositions and mechanical processes used during spinning filament yarns may vary among manufacturers, after drawing or spinning, the polymer filament yarns are heated to drive off non-carbon atoms, producing the final carbon fiber