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73-432: Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood , rags , grasses , herbivore dung , or other vegetable sources in water . Once the water is drained through a fine mesh leaving the fibre evenly distributed on the surface, it can be pressed and dried. The papermaking process developed in east Asia, probably China , at least as early as 105 CE , by

146-405: A smoke source to a wood fire. In cooking , lignin in the form of hardwood is an important source of these two compounds, which impart the characteristic aroma and taste to smoked foods such as barbecue . The main flavor compounds of smoked ham are guaiacol , and its 4-, 5-, and 6-methyl derivatives as well as 2,6-dimethylphenol. These compounds are produced by thermal breakdown of lignin in

219-439: A composite and / or tuning the shape , geometry , size , orientation and arrangement to achieve the desired property. In foams and textiles , the chemical structure is less relevant to immediately observable properties than larger-scale material features: the holes in foams, and the weave in textiles. Materials can be compared and classified by their large-scale physical properties. Mechanical properties determine how

292-423: A crucial part in conducting water and aqueous nutrients in plant stems. The polysaccharide components of plant cell walls are highly hydrophilic and thus permeable to water, whereas lignin is more hydrophobic . The crosslinking of polysaccharides by lignin is an obstacle for water absorption to the cell wall. Thus, lignin makes it possible for the plant's vascular tissue to conduct water efficiently. Lignin

365-468: A given application. The relevant structure of materials has a different length scale depending on the material. The structure and composition of a material can be determined by microscopy or spectroscopy . In engineering , materials can be categorised according to their microscopic structure: A metamaterial is any material engineered to have a property that is not found in naturally occurring materials, usually by combining several materials to form

438-544: A lower redox potential than guaiacyl units. Because it is cross-linked with the other cell wall components, lignin minimizes the accessibility of cellulose and hemicellulose to microbial enzymes, leading to a reduced digestibility of biomass. Some ligninolytic enzymes include heme peroxidases such as lignin peroxidases , manganese peroxidases , versatile peroxidases , and dye-decolourizing peroxidases as well as copper-based laccases . Lignin peroxidases oxidize non-phenolic lignin, whereas manganese peroxidases only oxidize

511-463: A material responds to applied forces . Examples include: Materials may degrade or undergo changes of properties at different temperatures. Thermal properties also include the material's thermal conductivity and heat capacity , relating to the transfer and storage of thermal energy by the material. Materials can be compared and categorized by any quantitative measure of their behavior under various conditions. Notable additional properties include

584-401: A more durable material than paper. Material Raw materials can be processed in different ways to influence their properties, by purification, shaping or the introduction of other materials. New materials can be produced from raw materials by synthesis . In industry , materials are inputs to manufacturing processes to produce products or more complex materials. Materials chart

657-663: A number of industrial and construction processes. The oldest known archaeological fragments of the immediate precursor to modern paper date to the 2nd century BCE in China . The pulp papermaking process is ascribed to Cai Lun , a 2nd-century CE Han court eunuch . It has been said that knowledge of papermaking was passed to the Islamic world after the Battle of Talas in 751 CE when two Chinese papermakers were captured as prisoners and used to extract 'the secrets' of papermaking. Although

730-525: A rag paper. The aging behaviour of a paper is determined by its manufacture, not the original source of the fibres. Furthermore, tests sponsored by the Library of Congress prove that all paper is at risk of acid decay, because cellulose itself produces formic, acetic, lactic and oxalic acids. Mechanical pulping yields almost a tonne of pulp per tonne of dry wood used, which is why mechanical pulps are sometimes referred to as "high yield" pulps. With almost twice

803-444: A renewable source of aromatic compounds for the chemical industry, with an addressable market of more than $ 130bn. Given that it is the most prevalent biopolymer after cellulose , lignin has been investigated as a feedstock for biofuel production and can become a crucial plant extract in the development of a new class of biofuels. Lignin biosynthesis begins in the cytosol with the synthesis of glycosylated monolignols from

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876-471: A substance under vacuum and at high temperature) with tetramethylammonium hydroxide (TMAH) or cupric oxide has also been used to characterize lignins. The ratio of syringyl lignol (S) to vanillyl lignol (V) and cinnamyl lignol (C) to vanillyl lignol (V) is variable based on plant type and can therefore be used to trace plant sources in aquatic systems (woody vs. non-woody and angiosperm vs. gymnosperm). Ratios of carboxylic acid (Ad) to aldehyde (Al) forms of

949-445: A variety of aluminium sulfate salt that is significantly acidic . Alum was added to paper to assist in sizing , making it somewhat water resistant so that inks did not "run" or spread uncontrollably. Early papermakers did not realize that the alum they added liberally to cure almost every problem encountered in making their product would be eventually detrimental. The cellulose fibres that make up paper are hydrolyzed by acid, and

1022-461: A wide variety of properties, depending on its intended use. It is estimated that paper-based storage solutions captured 0.33% of the total in 1986 and only 0.007% in 2007, even though in absolute terms the world's capacity to store information on paper increased from 8.7 to 19.4 petabytes . It is estimated that in 1986 paper-based postal letters represented less than 0.05% of the world's telecommunication capacity, with sharply decreasing tendency after

1095-443: Is uncoated . Coated paper has a thin layer of material such as calcium carbonate or china clay applied to one or both sides in order to create a surface more suitable for high-resolution halftone screens. (Uncoated papers are rarely suitable for screens above 150 lpi.) Coated or uncoated papers may have their surfaces polished by calendering . Coated papers are divided into matte, semi-matte or silk, and gloss. Gloss papers give

1168-523: Is 63.4% carbon, 5.9% hydrogen, 0.7% ash (mineral components), and 30% oxygen (by difference), corresponding approximately to the formula (C 31 H 34 O 11 ) n . Lignin is a collection of highly heterogeneous polymers derived from a handful of precursor lignols. Heterogeneity arises from the diversity and degree of crosslinking between these lignols. The lignols that crosslink are of three main types, all derived from phenylpropane: coniferyl alcohol (3-methoxy-4-hydroxyphenylpropane; its radical, G,

1241-490: Is a lamination of natural plant fibre, while paper is manufactured from fibres whose properties have been changed by maceration. To make pulp from wood, a chemical pulping process separates lignin from cellulose fibre. A cooking liquor is used to dissolve the lignin , which is then washed from the cellulose ; this preserves the length of the cellulose fibres. Paper made from chemical pulps are also known as wood-free papers (not to be confused with tree-free paper ); this

1314-437: Is a radical-radical coupling, is catalysed by oxidative enzymes . Both peroxidase and laccase enzymes are present in the plant cell walls , and it is not known whether one or both of these groups participates in the polymerisation. Low molecular weight oxidants might also be involved. The oxidative enzyme catalyses the formation of monolignol radicals . These radicals are often said to undergo uncatalyzed coupling to form

1387-454: Is a thick, paper-like material produced from the pith of the Cyperus papyrus plant, which was used in ancient Egypt and other Mediterranean cultures for writing before the introduction of paper. Although the word paper is etymologically derived from papyrus , the two are produced very differently and the development of the first is distinct from the development of the second. Papyrus

1460-405: Is achieved through a more environmentally viable process than generic plastic manufacturing. Lignin removed by the kraft process is usually burned for its fuel value, providing energy to power the paper mill. Two commercial processes exist to remove lignin from black liquor for higher value uses: LignoBoost (Sweden) and LignoForce (Canada). Higher quality lignin presents the potential to become

1533-574: Is another specialty process used to pulp straws , bagasse and hardwoods with high silicate content. There are two major mechanical pulps: thermomechanical pulp (TMP) and groundwood pulp (GW). In the TMP process, wood is chipped and then fed into steam-heated refiners, where the chips are squeezed and converted to fibres between two steel discs. In the groundwood process, debarked logs are fed into grinders where they are pressed against rotating stones to be made into fibres. Mechanical pulping does not remove

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1606-451: Is because they do not contain lignin, which deteriorates over time. The pulp can also be bleached to produce white paper, but this consumes 5% of the fibres. Chemical pulping processes are not used to make paper made from cotton, which is already 90% cellulose. There are three main chemical pulping processes: the sulfite process dates back to the 1840s and was the dominant method before the second world war. The kraft process , invented in

1679-471: Is colored, it yellows in air, and its presence weakens the paper. Once separated from the cellulose, it is burned as fuel. Only a fraction is used in a wide range of low volume applications where the form but not the quality is important. Mechanical, or high-yield pulp , which is used to make newsprint , still contains most of the lignin originally present in the wood. This lignin is responsible for newsprint's yellowing with age. High quality paper requires

1752-475: Is considered card. The weight of a ream therefore depends on the dimensions of the paper and its thickness. Most commercial paper sold in North America is cut to standard paper sizes based on customary units and is defined by the length and width of a sheet of paper. The ISO 216 system used in most other countries is based on the surface area of a sheet of paper, not on a sheet's width and length. It

1825-496: Is cut to width with holes punched at the edges, and folded into stacks. All paper produced by paper machines such as the Fourdrinier Machine are wove paper, i.e. the wire mesh that transports the web leaves a pattern that has the same density along the paper grain and across the grain. Textured finishes, watermarks and wire patterns imitating hand-made laid paper can be created by the use of appropriate rollers in

1898-463: Is derived from the coniferyl alcohol , which gives rise to G upon pyrolysis. In angiosperms some of the coniferyl alcohol is converted to S. Thus, lignin in angiosperms has both G and S components. Lignin's molecular masses exceed 10,000 u . It is hydrophobic as it is rich in aromatic subunits. The degree of polymerisation is difficult to measure, since the material is heterogeneous. Different types of lignin have been described depending on

1971-416: Is digested by " Alteromonas-like sub-group " bacteria symbionts in the typhlosole sub-organ of its cecum . Pyrolysis of lignin during the combustion of wood or charcoal production yields a range of products, of which the most characteristic ones are methoxy -substituted phenols . Of those, the most important are guaiacol and syringol and their derivatives. Their presence can be used to trace

2044-417: Is formed as a paper web and the water is removed from it by pressing and drying. Pressing the sheet removes the water by force. Once the water is forced from the sheet, a special kind of felt, which is not to be confused with the traditional one, is used to collect the water. When making paper by hand, a blotter sheet is used instead. Drying involves using air or heat to remove water from the paper sheets. In

2117-594: Is present in all vascular plants , but not in bryophytes , supporting the idea that the original function of lignin was restricted to water transport. It is covalently linked to hemicellulose and therefore cross-links different plant polysaccharides , conferring mechanical strength to the cell wall and by extension the plant as a whole. Its most commonly noted function is the support through strengthening of wood (mainly composed of xylem cells and lignified sclerenchyma fibres) in vascular plants. Finally, lignin also confers disease resistance by accumulating at

2190-462: Is sometimes called guaiacyl), sinapyl alcohol (3,5-dimethoxy-4-hydroxyphenylpropane; its radical, S, is sometimes called syringyl), and paracoumaryl alcohol (4-hydroxyphenylpropane; its radical, H, is sometimes called 4-hydroxyphenyl). The relative amounts of the precursor "monomers" (lignols or monolignols) vary according to the plant source. Lignins are typically classified according to their syringyl/guaiacyl (S/G) ratio. Lignin from gymnosperms

2263-749: The Han court eunuch Cai Lun , although the earliest archaeological fragments of paper derive from the 2nd century BCE in China. Although paper was originally made in single sheets by hand, today it is mass-produced on large machines—some making reels 10 metres wide, running at 2,000 metres per minute and up to 600,000 tonnes a year. It is a versatile material with many uses, including printing , painting, graphics, signage, design, packaging, decorating, writing , and cleaning . It may also be used as filter paper, wallpaper, book endpaper, conservation paper, laminated worktops, toilet tissue, currency, and security paper, or in

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2336-584: The Stockholm Convention on Persistent Organic Pollutants . Dioxins are highly toxic, and health effects on humans include reproductive, developmental, immune and hormonal problems. They are known to be carcinogenic. Over 90% of human exposure is through food, primarily meat, dairy, fish and shellfish, as dioxins accumulate in the food chain in the fatty tissue of animals. The paper pulp and print industries emitted together about 1% of world greenhouse-gas emissions in 2010 and about 0.9% in 2012. In

2409-416: The amino acid phenylalanine . These first reactions are shared with the phenylpropanoid pathway. The attached glucose renders them water-soluble and less toxic . Once transported through the cell membrane to the apoplast , the glucose is removed, and the polymerisation commences. Much about its anabolism is not understood even after more than a century of study. The polymerisation step, that

2482-491: The hydrogen bonds in the paper can be broken and fibres separated again. Most recycled paper contains a proportion of virgin fibre for the sake of quality; generally speaking, de-inked pulp is of the same quality or lower than the collected paper it was made from. There are three main classifications of recycled fibre: Recycled papers can be made from 100% recycled materials or blended with virgin pulp, although they are (generally) not as strong nor as bright as papers made from

2555-479: The lignin , so the yield is very high, > 95%; however, lignin causes the paper thus produced to turn yellow and become brittle over time. Mechanical pulps have rather short fibres, thus producing weak paper. Although large amounts of electrical energy are required to produce mechanical pulp, it costs less than the chemical kind. Paper recycling processes can use either chemically or mechanically produced pulp; by mixing it with water and applying mechanical action

2628-488: The wood used in the smokehouse. The conventional method for lignin quantitation in the pulp industry is the Klason lignin and acid-soluble lignin test, which is standardized procedures. The cellulose is digested thermally in the presence of acid. The residue is termed Klason lignin. Acid-soluble lignin (ASL) is quantified by the intensity of its Ultraviolet spectroscopy . The carbohydrate composition may be also analyzed from

2701-448: The 1870s and first used in the 1890s, is now the most commonly practised strategy; one of its advantages is the chemical reaction with lignin produces heat, which can be used to run a generator. Most pulping operations using the kraft process are net contributors to the electricity grid or use the electricity to run an adjacent paper mill. Another advantage is that this process recovers and reuses all inorganic chemical reagents. Soda pulping

2774-679: The 2022−2024 edition of the annual "Pulp and paper capacites survey", the Food and Agriculture Organization of the United Nations (FAO) reports that Asia has superseded North America as the top pulp and paper producing continent. FAO figures for 2021 show the production of graphic papers continuing its decline from a mid-2000s peak to hover below 100 million tonnes a year. By contrast, the production of other papers and paperboard – which includes cardboard and sanitary products – has continued to soar, exceeding 320 million tonnes. FAO has documented

2847-562: The H 2 O 2 required for the function of lignin peroxidase and other heme peroxidases . Bacteria lack most of the enzymes employed by fungi to degrade lignin, and lignin derivatives (aliphatic acids, furans, and solubilized phenolics) inhibit the growth of bacteria. Yet, bacterial degradation can be quite extensive, especially in aquatic systems such as lakes, rivers, and streams, where inputs of terrestrial material (e.g. leaf litter ) can enter waterways. The ligninolytic activity of bacteria has not been studied extensively even though it

2920-498: The Klason liquors, although there may be sugar breakdown products (furfural and 5-hydroxymethylfurfural ). A solution of hydrochloric acid and phloroglucinol is used for the detection of lignin (Wiesner test). A brilliant red color develops, owing to the presence of coniferaldehyde groups in the lignin. Thioglycolysis is an analytical technique for lignin quantitation . Lignin structure can also be studied by computational simulation. Thermochemolysis (chemical break down of

2993-554: The United States alone. The average office worker in the US prints 31 pages every day. Americans also use in the order of 16 billion paper cups per year. Conventional bleaching of wood pulp using elemental chlorine produces and releases into the environment large amounts of chlorinated organic compounds , including chlorinated dioxins . Dioxins are recognized as a persistent environmental pollutant, regulated internationally by

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3066-547: The United States and in micrometres (μm) in the rest of the world. Paper may be between 0.07 and 0.18 millimetres (0.0028 and 0.0071 in) thick. Paper is often characterized by weight. In the United States, the weight is the weight of a ream (bundle of 500 sheets) of varying "basic sizes" before the paper is cut into the size it is sold to end customers. For example, a ream of 20 lb, 8.5 in × 11 in (216 mm × 279 mm) paper weighs 5 pounds because it has been cut from larger sheets into four pieces. In

3139-501: The United States, printing paper is generally 20 lb, 24 lb, 28 lb, or 32 lb at most. Cover stock is generally 68 lb, and 110 lb or more is considered card stock . In Europe and other regions using the ISO 216 paper-sizing system, the weight is expressed in grams per square metre (g/m or usually gsm) of the paper. Printing paper is generally between 60 gsm and 120 gsm. Anything heavier than 160 gsm

3212-540: The cost of manufacturing paper. In 1844, the Canadian inventor Charles Fenerty and the German inventor Friedrich Gottlob Keller independently developed processes for pulping wood fibres. Before the industrialisation of paper production the most common fibre source was recycled fibres from used textiles, called rags. The rags were from hemp , linen and cotton . A process for removing printing inks from recycled paper

3285-480: The dry mass of wood. Lignin is present in red algae , which suggest that the common ancestor of plants and red algae may have been pre-adapted to synthesize lignin. This finding also suggests that the original function of lignin may have been structural as it plays this role in the red alga Calliarthron , where it supports joints between calcified segments. The composition of lignin varies from species to species. An example of composition from an aspen sample

3358-560: The earliest days of papermaking, this was done by hanging the sheets like laundry; in more modern times, various forms of heated drying mechanisms are used. On the paper machine, the most common is the steam-heated can dryer. These can reach temperatures above 93 °C (200 °F) and are used in long sequences of more than forty cans where the heat produced by these can easily dry the paper to less than six percent moisture. The paper may then undergo sizing to alter its physical properties for use in various applications. Paper at this point

3431-413: The environment, lignin can be degraded either biotically via bacteria or abiotically via photochemical alteration, and oftentimes the latter assists in the former. In addition to the presence or absence of light, several of environmental factors affect the biodegradability of lignin, including bacterial community composition, mineral associations, and redox state. In shipworms , the lignin it ingests

3504-442: The expanding production of cardboard in paper and paperboard, which has been increasing in response to the spread of e-commerce since the 2010s. Data from FAO suggest that it has been even further boosted by COVID-19-related lockdowns. Some manufacturers have started using a new, significantly more environmentally friendly alternative to expanded plastic packaging. Made out of paper, and known commercially as PaperFoam,

3577-417: The highest optical density in the printed image. The paper is then fed onto reels if it is to be used on web printing presses, or cut into sheets for other printing processes or other purposes. The fibres in the paper basically run in the machine direction. Sheets are usually cut "long-grain", i.e. with the grain parallel to the longer dimension of the sheet. Continuous form paper (or continuous stationery)

3650-451: The history of humanity. The system of the three prehistoric ages ( Stone Age , Bronze Age , Iron Age ) were succeeded by historical ages: steel age in the 19th century, polymer age in the middle of the following century (plastic age) and silicon age in the second half of the 20th century. Materials can be broadly categorized in terms of their use, for example: Material selection is a process to determine which material should be used for

3723-413: The later stages of the machine. Wove paper does not exhibit "laidlines", which are small regular lines left behind on paper when it was handmade in a mould made from rows of metal wires or bamboo. Laidlines are very close together. They run perpendicular to the "chainlines", which are further apart. Handmade paper similarly exhibits "deckle edges", or rough and feathery borders. Paper can be produced with

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3796-422: The latter. Besides the fibres, pulps may contain fillers such as chalk or china clay , which improve its characteristics for printing or writing. Additives for sizing purposes may be mixed with it or applied to the paper web later in the manufacturing process; the purpose of such sizing is to establish the correct level of surface absorbency to suit ink or paint. The pulp is fed to a paper machine, where it

3869-435: The lignin polymer . An alternative theory invokes an unspecified biological control. In contrast to other bio-polymers (e.g. proteins, DNA, and even cellulose), lignin resists degradation. It is immune to both acid- and base-catalyzed hydrolysis. The degradability varies with species and plant tissue type. For example, syringyl (S) lignin is more susceptible to degradation by fungal decay as it has fewer aryl-aryl bonds and

3942-405: The lignin in lignocellulose , but others lack this ability. Most fungal lignin degradation involves secreted peroxidases . Many fungal laccases are also secreted, which facilitate degradation of phenolic lignin-derived compounds, although several intracellular fungal laccases have also been described. An important aspect of fungal lignin degradation is the activity of accessory enzymes to produce

4015-427: The lignols (Ad/Al) reveal diagenetic information, with higher ratios indicating a more highly degraded material. Increases in the (Ad/Al) value indicate an oxidative cleavage reaction has occurred on the alkyl lignin side chain which has been shown to be a step in the decay of wood by many white-rot and some soft rot fungi . Lignin and its models have been well examined by H and C NMR spectroscopy. Owing to

4088-420: The massive introduction of digital technologies. Paper has a major role in the visual arts. It is used by itself to form two- and three-dimensional shapes and collages . It has also evolved to being a structural material used in furniture design. Watercolor paper has a long history of production and use. The thickness of paper is often measured by caliper, which is typically given in thousandths of an inch in

4161-444: The means of isolation. Many grasses have mostly G, while some palms have mainly S. All lignins contain small amounts of incomplete or modified monolignols, and other monomers are prominent in non-woody plants. Lignin fills the spaces in the cell wall between cellulose , hemicellulose , and pectin components, especially in vascular and support tissues: xylem tracheids , vessel elements and sclereid cells. Lignin plays

4234-517: The new packaging has mechanical properties very similar to those of some expanded plastic packaging, but is biodegradable and can also be recycled with ordinary paper. With increasing environmental concerns about synthetic coatings (such as PFOA ) and the higher prices of hydrocarbon based petrochemicals, there is a focus on zein (corn protein) as a coating for paper in high grease applications such as popcorn bags. Also, synthetics such as Tyvek and Teslin have been introduced as printing media as

4307-463: The office and the home are A4 and A3 (A3 is the size of two A4 sheets). The density of paper ranges from 250 kg/m (16 lb/cu ft) for tissue paper to 1 500  kg/m (94 lb/cu ft) for some specialty paper. Printing paper is about 800 kg/m (50 lb/cu ft). Paper may be classified into seven categories: Some paper types include: Much of the early paper made from wood pulp contained significant amounts of alum ,

4380-498: The optical, electrical, and magnetic behavior of materials. Lignin Lignin is a class of complex organic polymers that form key structural materials in the support tissues of most plants. Lignins are particularly important in the formation of cell walls , especially in wood and bark , because they lend rigidity and do not rot easily. Chemically, lignins are polymers made by cross-linking phenolic precursors. Lignin

4453-459: The past 40 years leading to increase in deforestation , with 35% of harvested trees being used for paper manufacture. Most paper companies also plant trees to help regrow forests. Logging of old growth forests accounts for less than 10% of wood pulp, but is one of the most controversial issues. Paper waste accounts for up to 40% of total waste produced in the United States each year, which adds up to 71.6 million tons of paper waste per year in

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4526-593: The phenolic structures. Dye-decolorizing peroxidases, or DyPs, exhibit catalytic activity on a wide range of lignin model compounds, but their in vivo substrate is unknown. In general, laccases oxidize phenolic substrates but some fungal laccases have been shown to oxidize non-phenolic substrates in the presence of synthetic redox mediators. Well-studied ligninolytic enzymes are found in Phanerochaete chrysosporium and other white rot fungi . Some white rot fungi, such as Ceriporiopsis subvermispora , can degrade

4599-428: The presence of alum eventually degrades the fibres until the acidic paper disintegrates in a process known as " slow fire ". Documents written on rag paper are significantly more stable. The use of non-acidic additives to make paper is becoming more prevalent, and the stability of these papers is less of an issue. Paper made from mechanical pulp contains significant amounts of lignin , a major component in wood. In

4672-427: The presence of light and oxygen, lignin reacts to give yellow materials, which is why newsprint and other mechanical paper yellows with age. Paper made from bleached kraft or sulfite pulps does not contain significant amounts of lignin and is therefore better suited for books, documents and other applications where whiteness of the paper is essential. Paper made from wood pulp is not necessarily less durable than

4745-434: The removal of lignin from the pulp. These delignification processes are core technologies of the papermaking industry as well as the source of significant environmental concerns. In sulfite pulping , lignin is removed from wood pulp as lignosulfonates , for which many applications have been proposed. They are used as dispersants , humectants , emulsion stabilizers , and sequestrants ( water treatment ). Lignosulfonate

4818-410: The site of pathogen infiltration, making the plant cell less accessible to cell wall degradation. Global commercial production of lignin is a consequence of papermaking. In 1988, more than 220 million tons of paper were produced worldwide. Much of this paper was delignified; lignin comprises about 1/3 of the mass of lignocellulose, the precursor to paper. Lignin is an impediment to papermaking as it

4891-580: The veracity of this story is uncertain, paper started to be made in Samarkand soon after. In the 13th century, the knowledge and uses of paper spread from the Middle East to medieval Europe , where the first water-powered paper mills were built. Because paper was introduced to the West through the city of Baghdad , it was first called bagdatikos . In the 19th century, industrialization greatly reduced

4964-410: The yield as chemical pulping, mechanical pulps is often cheaper. Mass-market paperback books and newspapers tend to use mechanical papers. Book publishers tend to use acid-free paper , made from fully bleached chemical pulps for hardback and trade paperback books. The production and use of paper has a number of adverse effects on the environment. Worldwide consumption of paper has risen by 400% in

5037-601: Was also the first family of water reducers or superplasticizers to be added in the 1930s as admixture to fresh concrete in order to decrease the water-to-cement ( w/c ) ratio, the main parameter controlling the concrete porosity , and thus its mechanical strength , its diffusivity and its hydraulic conductivity , all parameters essential for its durability. It has application in environmentally sustainable dust suppression agent for roads. Also, lignin can be used in making biodegradable plastic along with cellulose as an alternative to hydrocarbon-made plastics if lignin extraction

5110-477: Was first adopted in Germany in 1922 and generally spread as nations adopted the metric system. The largest standard size paper is A0 (A zero), measuring one square metre (approx. 1189 × 841 mm). A1 is half the size of a sheet of A0 (i.e., 594 mm × 841 mm), such that two sheets of A1 placed side by side are equal to one sheet of A0. A2 is half the size of a sheet of A1, and so forth. Common sizes used in

5183-417: Was first described in 1930. Many bacterial DyPs have been characterized. Bacteria do not express any of the plant-type peroxidases (lignin peroxidase, Mn peroxidase, or versatile peroxidases), but three of the four classes of DyP are only found in bacteria. In contrast to fungi, most bacterial enzymes involved in lignin degradation are intracellular, including two classes of DyP and most bacterial laccases. In

5256-654: Was first mentioned in 1813 by the Swiss botanist A. P. de Candolle , who described it as a fibrous, tasteless material, insoluble in water and alcohol but soluble in weak alkaline solutions, and which can be precipitated from solution using acid. He named the substance "lignine", which is derived from the Latin word lignum , meaning wood. It is one of the most abundant organic polymers on Earth , exceeded only by cellulose and chitin . Lignin constitutes 30% of terrestrial non- fossil organic carbon on Earth, and 20 to 35% of

5329-470: Was invented by German jurist Justus Claproth in 1774. Today this method is called deinking . It was not until the introduction of wood pulp in 1843 that paper production was not dependent on recycled materials from ragpickers . The word paper is etymologically derived from Latin papyrus , which comes from the Greek πᾰ́πῡρος ( pápūros ), the word for the Cyperus papyrus plant. Papyrus

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