|
Deacidification
Mass deacidification is a term used in library and information science as one possible measure against the degradation of paper in old books, the so-called " slow fires". The goal of the process is to increase the pH of acidic paper. Although acid-free paper has become more common, a large body of acidic paper still exists in books made after the 1850s; this is because of its cheaper and simpler production methods. Acidic paper, especially when exposed to light, air pollution, or high relative humidity, yellows and becomes brittle over time. During mass deacidification an alkaline agent is deposited in the paper to neutralize existing acid and prevent further decay. Mass deacidification is intended for objects on acidic paper that will be lost if no action is performed. History of research and process development Mass deacidification — along with microfilm and lamination — was developed during the early and mid-20th century as a response to the chemical process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preservation (library And Archival Science)
In Library science, library and archival science, preservation is a set of preventive conservation activities aimed at prolonging the life of a record, book, or object while making as few changes as possible. Preservation activities vary widely and may include monitoring the condition of items, maintaining the temperature and humidity in collection storage areas, writing a plan in case of emergencies, digitizing items, writing relevant metadata, and increasing accessibility. Preservation, in this definition, is practiced in a library or an archive by a librarian, archivist, or other professional when they perceive a record is in need of maintenance. Preservation should be distinguished from interventive Conservation and restoration of books, manuscripts, documents and ephemera, conservation and restoration, which refers to the treatment and repair of individual items to slow the process of decay, or restore them to a usable state. Preventive conservation is occasionally used int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double Fold
''Double Fold: Libraries and the Assault on Paper'' is a non-fiction book by Nicholson Baker that was published in April 2001. An excerpt appeared in the July 24, 2000 issue of ''The New Yorker'', under the title "Deadline: The Author's Desperate Bid to Save America's Past." This exhaustively researched work (there are 63 pages of endnotes and 18 pages of references in the paperback edition) details Baker's quest to uncover the fate of thousands of books and newspapers that were replaced and often destroyed during the microfilming boom of the 1980s and 1990s. ''Double Fold'' is a controversial work and is not meant to be objective. In the preface, Baker says, "This isn't an impartial piece of reporting", (preface p. x) and ''The New York Times'' characterized the book as a "blistering and thoroughly idiosyncratic attack". Overview The term " double fold" refers to the test used by many librarians and preservation administrators to determine the brittleness and "usability" of pap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slow Fire
A slow fire is a term used in library and information science to describe paper embrittlement resulting from acid decay. The term is taken from the title of Terry Sanders's 1987 film ''Slow Fires: On the preservation of the human record.'' Solutions to this problem include the use of acid-free paper stocks, reformatting brittle books by microfilming, photocopying or digitization, and a variety of deacidification techniques. See also *Acidic paper *Acid-free paper *Double Fold ''Double Fold: Libraries and the Assault on Paper'' is a non-fiction book by Nicholson Baker that was published in April 2001. An excerpt appeared in the July 24, 2000 issue of ''The New Yorker'', under the title "Deadline: The Author's Desperat ... * Wood-pulp paper * Preservation: Library and Archival Science External links ''International Journal of Library Science '' [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Book
A book is a medium for recording information in the form of writing or images, typically composed of many pages (made of papyrus, parchment, vellum, or paper) bound together and protected by a cover. The technical term for this physical arrangement is ''codex'' (plural, ''codices''). In the history of hand-held physical supports for extended written compositions or records, the codex replaces its predecessor, the scroll. A single sheet in a codex is a leaf and each side of a leaf is a page. As an intellectual object, a book is prototypically a composition of such great length that it takes a considerable investment of time to compose and still considered as an investment of time to read. In a restricted sense, a book is a self-sufficient section or part of a longer composition, a usage reflecting that, in antiquity, long works had to be written on several scrolls and each scroll had to be identified by the book it contained. Each part of Aristotle's '' Physics'' is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paper
Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed on the surface, followed by pressing and drying. Although paper was originally made in single sheets by hand, almost all is now made 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 Housekeeping, cleaning. It may also be used as filter paper, wallpaper, book endpaper, conservation paper, laminated worktops, toilet tissue, or currency and security paper, or in a number of industrial and construction processes. The papermaking process developed in east Asia, probably China, at least as early as 105 Common Era, CE, by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid-free Paper
Acid-free paper is paper that, if infused in water, yields a neutral or basic pH (7 or slightly greater). It can be made from any cellulose fiber as long as the active acid pulp is eliminated during processing. It is also lignin- and sulfur-free. Acid-free paper addresses the problem of preserving documents and preserving artwork for long periods. Overview Paper made from wood-based pulp that has not had its lignin removed turns yellow, becomes brittle, and deteriorates over time. When exposed to light and/or heat, the molecules in the acidic paper will break down even faster. Acidic wood-pulp paper became commonplace in the late 19th century, and in the 1930s William Barrow (a chemist and librarian) published a report about the deterioration of acidic paper in the libraries. For fear of the gradual disintegration of written materials, measures have since been taken to improve the quality of paper. During production, acid-free paper may be treated with a mild base (usually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paper
Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed on the surface, followed by pressing and drying. Although paper was originally made in single sheets by hand, almost all is now made 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 Housekeeping, cleaning. It may also be used as filter paper, wallpaper, book endpaper, conservation paper, laminated worktops, toilet tissue, or currency and security paper, or in a number of industrial and construction processes. The papermaking process developed in east Asia, probably China, at least as early as 105 Common Era, CE, by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Library Of Congress
The Library of Congress (LOC) is the research library that officially serves the United States Congress and is the ''de facto'' national library of the United States. It is the oldest federal cultural institution in the country. The library is housed in three buildings on Capitol Hill in Washington, D.C.; it also maintains a conservation center in Culpeper, Virginia. The library's functions are overseen by the Librarian of Congress, and its buildings are maintained by the Architect of the Capitol. The Library of Congress is one of the largest libraries in the world. Its "collections are universal, not limited by subject, format, or national boundary, and include research materials from all parts of the world and in more than 470 languages." Congress moved to Washington, D.C., in 1800 after holding sessions for eleven years in the temporary national capitals in New York City and Philadelphia. In both cities, members of the U.S. Congress had access to the sizable colle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethylzinc
Diethylzinc (C2H5)2Zn, or DEZ, is a highly pyrophoric and reactive organozinc compound consisting of a zinc center bound to two ethyl groups. This colourless liquid is an important reagent in organic chemistry. It is available commercially as a solution in hexanes, heptane, or toluene, or as a pure liquid. Synthesis Edward Frankland first reported the compound in 1848 from zinc and ethyl iodide, the first organozinc compound discovered. He improved the synthesis by using diethyl mercury as starting material. The contemporary synthesis consists of the reaction of a 1:1 mixture of ethyl iodide and ethyl bromide with a zinc-copper couple, a source of reactive zinc. Structure The compound crystallizes in a tetragonal body-centered unit cell of space group symmetry I41md. In the solid-state diethylzinc shows nearly linear Zn centres. The Zn-C bonds measure 194.8(5) pm, while the C-Zn-C angle is slightly bent with 176.2(4)°. The structure of the gas-phase shows a very simi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Oxide
Magnesium oxide ( Mg O), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of MgO and consists of a lattice of Mg2+ ions and O2− ions held together by ionic bonding. Magnesium hydroxide forms in the presence of water (MgO + H2O → Mg(OH)2), but it can be reversed by heating it to remove moisture. Magnesium oxide was historically known as magnesia alba (literally, the white mineral from Magnesia), to differentiate it from '' magnesia negra'', a black mineral containing what is now known as manganese. Related oxides While "magnesium oxide" normally refers to MgO, the compound magnesium peroxide MgO2 is also known. According to evolutionary crystal structure prediction, MgO2 is thermodynamically stable at pressures above 116 GPa (gigapascals), and a semiconducting suboxide Mg3O2 is thermodynamically stable above 500 GPa. Because of its stability, MgO is used as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newton's Rings
Newton's rings is a phenomenon in which an interference pattern is created by the reflection of light between two surfaces, typically a spherical surface and an adjacent touching flat surface. It is named after Isaac Newton, who investigated the effect in 1666. When viewed with monochromatic light, Newton's rings appear as a series of concentric, alternating bright and dark rings centered at the point of contact between the two surfaces. When viewed with white light, it forms a concentric ring pattern of rainbow colors because the different wavelengths of light interfere at different thicknesses of the air layer between the surfaces. History The phenomenon was first described by Robert Hooke in his 1665 book ''Micrographia''. Its name derives from the mathematician and physicist Sir Isaac Newton, who studied the phenomenon in 1666 while sequestered at home in Lincolnshire in the time of the Great Plague that had shut down Trinity College, Cambridge. He recorded his observations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slovak University Of Technology In Bratislava
Slovak University of Technology in Bratislava (STU) ( sk, Slovenská technická univerzita v Bratislave) is the biggest and oldest university of technology in Slovakia. In the 2012 Academic Ranking of World Universities it was ranked in the first 150 in Computer Science, the only university in central Europe in the first 200. However, it lost this position in the two following years. University structure * Faculty of Civil Engineering * Faculty of Mechanical Engineering * Faculty of Electrical Engineering and Information Technology * Faculty of Chemical and Food Technology * Faculty of Architecture and Design * Faculty of Materials Science and Technology (in Trnava) * Faculty of Informatics and Information Technologies * Institute of Management * Institute of Engineering Studies European Alliance for Innovation The Slovak University of Technology in Bratislava signed a Memorandum of Understandinghttp://www.stuba.sk/sk/vyskume/europska-aliancia-pre-inovacie-na-stu.html?p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
