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Litmus
Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. It is a purple dye that is extracted from a type of algal bloom called ‘lichens’. In an acidic medium, blue litmus paper turns red, and red litmus paper turns blue in a basic or alkaline medium. History The word "litmus" comes from an Old Norse word for "pulp". About 1300 the Spanish physician Arnaldus de Villa Nova began using litmus to study acids and bases. From the 16th century onwards, the blue dye was extracted from some lichens, especially in the Netherlands. Natural sources Litmus can be found in different species of lichens. The dyes are extracted from such species as ''Roccella tinctoria'' (South American), ''Roccella fuciformis'' (Angola and Madagascar), ''Roccella pygmaea'' (Algeria), ''Roccella phycopsis'', '' Lecanora tartarea'' (Norway, Sweden), ''Var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litmus Paper
Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. It is a purple dye that is extracted from a type of algal bloom called ‘lichens’. In an acidic medium, blue litmus paper turns red, and red litmus paper turns blue in a basic or alkaline medium. History The word "litmus" comes from an Old Norse word for "pulp". About 1300 the Spanish physician Arnaldus de Villa Nova began using litmus to study acids and bases. From the 16th century onwards, the blue dye was extracted from some lichens, especially in the Netherlands. Natural sources Litmus can be found in different species of lichens. The dyes are extracted from such species as ''Roccella tinctoria'' (South American), ''Roccella fuciformis'' (Angola and Madagascar), ''Roccella pygmaea'' (Algeria), ''Roccella phycopsis'', '' Lecanora tartarea'' (Norway, Sweden), ''Var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litmus Paper
Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. It is a purple dye that is extracted from a type of algal bloom called ‘lichens’. In an acidic medium, blue litmus paper turns red, and red litmus paper turns blue in a basic or alkaline medium. History The word "litmus" comes from an Old Norse word for "pulp". About 1300 the Spanish physician Arnaldus de Villa Nova began using litmus to study acids and bases. From the 16th century onwards, the blue dye was extracted from some lichens, especially in the Netherlands. Natural sources Litmus can be found in different species of lichens. The dyes are extracted from such species as '' Roccella tinctoria'' (South American), '' Roccella fuciformis'' (Angola and Madagascar), '' Roccella pygmaea'' (Algeria), '' Roccella phycopsis'', ''Lecanora tartarea'' (Norway, Sw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichens
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among hypha, filaments of multiple fungus, fungi species in a mutualism (biology), mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not plants. They may have tiny, leafless branches (fruticose); flat leaf-like structures (foliose); grow crust-like, adhering tightly to a surface (substrate) like a thick coat of paint (crustose); have a powder-like appearance (Leprose lichen, leprose); or other growth forms. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches (); flat leaf-like structures ( |
PH Indicator
A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH (acidity or basicity) of the solution can be determined visually or spectroscopically by changes in absorption and/or emission properties. Hence, a pH indicator is a chemical detector for hydronium ions (H3O+) or hydrogen ions (H+) in the Arrhenius model. Normally, the indicator causes the color of the solution to change depending on the pH. Indicators can also show change in other physical properties; for example, olfactory indicators show change in their odor. The pH value of a neutral solution is 7.0 at 25°C ( standard laboratory conditions). Solutions with a pH value below 7.0 are considered acidic and solutions with pH value above 7.0 are basic. Since most naturally occurring organic compounds are weak electrolytes, such as carboxylic acids and amines, pH indicators find many applications in biology and analytical chemistry. Moreover, pH indicators form one of the three main ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases, and Lewis bases. All definitions agree that bases are substances that react with acids, as originally proposed by G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form Hydroxide ions OH−. These ions can react with hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction An acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their applica .... A base was therefore a metal hydroxide such as Sodium hydroxide, NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases, and Lewis bases. All definitions agree that bases are substances that react with acids, as originally proposed by G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form Hydroxide ions OH−. These ions can react with hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction An acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their applica .... A base was therefore a metal hydroxide such as Sodium hydroxide, NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roccella Tinctoria
''Roccella tinctoria'' is a lichenised species of fungus in the genus ''Roccella'', homotypic synonym of ''Lecanora tinctoria'' (DC.) Czerwiak., 1849. It was first described by Augustin Pyramus de Candolle in 1805. It has the following varieties: * ''R. t.'' var. ''portentosa'' * ''R. t.'' var. ''subpodicellata'' * ''R. t.'' var. ''tinctoria'' and formae: * ''R. t.'' f. ''complanata'' * ''R. t.'' f. ''tinctoria'' Uses It is used to make litmus, a mixture of several organic compounds. Lichen has been used for centuries to make dyes. This includes royal purple colors derived from roccella tinctoria, also known as orseille. The process of making this dye was a secret and lead to the wealth of the weavers of Grainville-la-Teinturière and the Rucellai family of Florence, whose family name is related with the latin name of the plant, ''oricellum''. There has been speculation that the abundance of roccella tinctoria on the Canary Islands offered a profit motive for Jean de Béthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roccella Phycopsis
''Roccella phycopsis'' is a species of lichen in the family Roccellaceae. A study of ''Roccella phycopsis'' in Tunisia revealed that it contains methyl orcellinate, a chemical compound of interest for its anti-inflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs remedy pain by reducing inflammation as o ... activity. References phycopsis Lichen species Lichens described in 1804 Lichens of North Africa Taxa named by Erik Acharius {{Arthoniomycetes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrographa Leucophoea
''Dendrographa'' is a genus of lichen-forming fungi in the family Roccellaceae The Roccellaceae are a family of fungi in the order Arthoniomycetes. Most taxa are lichenized with green algae, although some are lichenicolous, growing on other lichens. Genera , Species Fungorum (in the Catalogue of Life) accepts 47 genera an .... It has seven species. It was given its current name by Otto Vernon Darbishire in 1895. Species *'' Dendrographa alectoroides'' *'' Dendrographa austrosorediata'' – Brazil *'' Dendrographa conformis'' *'' Dendrographa decolorans'' *'' Dendrographa franciscana'' *'' Dendrographa latebrarum'' *'' Dendrographa leucophaea'' References Roccellaceae Arthoniomycetes genera Lichen genera Taxa named by Otto Vernon Darbishire Taxa described in 1895 {{Arthoniomycetes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid (chemistry)
In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequence of database operations that satisfies the ACID properties (which can be perceived as a single logical operation on the data) is called a ''transaction''. For example, a transfer of funds from one bank account to another, even involving multiple changes such as debiting one account and crediting another, is a single transaction. In 1983, Andreas Reuter and Theo Härder coined the acronym ''ACID'', building on earlier work by Jim Gray who named atomicity, consistency, and durability, but not isolation, when characterizing the transaction concept. These four properties are the major guarantees of the transaction paradigm, which has influenced many aspects of development in database systems. According to Gray and Reuter, the IBM Informa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roccella Montagnei
''Roccella'' is a genus of 23 species of lichens in the family Roccellaceae. The genus was circumscribed by Swiss botanist Augustin Pyramus de Candolle in 1805, with ''Roccella fuciformis'' as the type species. Species *'' Roccella albida'' *'' Roccella bajasurensis'' *'' Roccella botrytis'' *'' Roccella colonii'' *'' Roccella elisabethae'' *'' Roccella floreana'' *''Roccella floribrassica'' *''Roccella fuciformis'' *'' Roccella fusca'' *'' Roccella geniculata'' – Galápagos Islands *''Roccella glebaria'' – Galápagos Islands *''Roccella gracilis'' *''Roccella hertelii'' *''Roccella incurvata'' *''Roccella kappeniana'' – Galápagos Islands *''Roccella maderensis'' *''Roccella minuta'' *''Roccella montagnei'' *''Roccella phycopsioides'' *''Roccella phycopsis'' *'' Roccella sanctae-helenae'' *'' Roccella stipitata'' – Galápagos Islands *''Roccella tinctoria ''Roccella tinctoria'' is a lichenised species of fungus in the genus ''Roccella'', homotyp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
