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Fold Number
Fold number refers to how many double fold, double folds that are required to cause rupture of a paper test piece under standardized conditions. Fold number is defined in ISO 5626:1993 as the antilogarithm of the mean folding endurance: f=\text_ \frac=10^ where ''f'' is the fold number, ''Fi'' is the folding endurance for each test piece and ''n'' is total number of test pieces used. In the introduction of ISO 5626:1993 it is emphasized that fold number, as defined in that very International Standard, does not equal the mean number of double folds observed. The latter is however still the definition used in some countries.ISO 5626:1993 Paper – Determination of folding endurance, Introduction. If the numerical value of the folding endurance is not rounded off, these will however be equal. In the former Swedish standard SS 152005 ("Pappersordlista") from 1992, with paper related terms defined in Swedish and English, fold number is explained as "the number of double folds which ... [...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". The work details Baker's project to uncover what happened to the thousands of books and newspapers that were replaced during the microfilming boom of the 1980s and 1990s. ''Double Fold'' has been a controversial work and Baker states in the preface that it is not meant to be objective: "This isn't an impartial piece of reporting" (p. x). ''The New York Times'' characterized the book as a "blistering, and thoroughly idiosyncratic, exposé." Overview The term " double fold" refers to the test used by many librarians and preservation administrators to determine the brittleness of paper. The test consists of folding down the corner of a page, then folding it back in the opposite direction. The action is then re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antilogarithm
In mathematics, the logarithm of a number is the exponent by which another fixed value, the base, must be raised to produce that number. For example, the logarithm of to base is , because is to the rd power: . More generally, if , then is the logarithm of to base , written , so . As a single-variable function, the logarithm to base is the inverse of exponentiation with base . The logarithm base is called the ''decimal'' or ''common'' logarithm and is commonly used in science and engineering. The ''natural'' logarithm has the number as its base; its use is widespread in mathematics and physics because of its very simple derivative. The ''binary'' logarithm uses base and is widely used in computer science, information theory, music theory, and photography. When the base is unambiguous from the context or irrelevant it is often omitted, and the logarithm is written . Logarithms were introduced by John Napier in 1614 as a means of simplifying calculations. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Folding Endurance
In paper testing, folding endurance is defined as the logarithm (to the base of ten) of the number of double folds that are required to make a test piece break under standardized conditions:ISO 5626:1993 Paper – Determination of folding endurance, 3.2. :''F'' = log10 ''d'', where ''F'' is the folding endurance and ''d'' the number of double folds. Folding endurance is especially applicable for papers used for maps, bank notes, archival documents, etc. The direction of the grain in relation to the folding line, the type of fibres used, the fibre contents, the calliper of the test piece, etc., as well as which type of folding tester that is used affect how many double folds a test piece can take. Folding endurance must not be confused with the related term fold number. Standards on folding endurance *ISO 5626: Paper – Determination of folding endurance. *TAPPI Test Method T 511: Folding endurance of paper (MIT tester). *TAPPI Test Method T 423: Folding endurance of pap ... [...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". The work details Baker's project to uncover what happened to the thousands of books and newspapers that were replaced during the microfilming boom of the 1980s and 1990s. ''Double Fold'' has been a controversial work and Baker states in the preface that it is not meant to be objective: "This isn't an impartial piece of reporting" (p. x). ''The New York Times'' characterized the book as a "blistering, and thoroughly idiosyncratic, exposé." Overview The term " double fold" refers to the test used by many librarians and preservation administrators to determine the brittleness of paper. The test consists of folding down the corner of a page, then folding it back in the opposite direction. The action is then re ... [...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, Feces#Other uses, 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 Common Era, CE, by the Han Dynasty, 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 Housekeeping, cleaning. It may also be used a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
