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An alpha privative or, rarely, [1] privative a (from Latin alpha prīvātīvum, from Ancient Greek α στερητικόν) is the prefix a-or an-(before vowels) that is used in Indo-European languages such as Sanskrit and Greek and in words borrowed therefrom to express negation or absence, for example the English words of Greek origin atypical, anesthetic, and analgesic.
There are two types of alpha-olefins, branched and linear (or normal). The chemical properties of branched alpha-olefins with a branch at either the second (vinylidene) or the third carbon number are significantly different from the properties of linear alpha-olefins and those with branches on the fourth carbon number and further from the start of the chain.
a-, called alpha privative, from Ancient Greek ἀ-, ἀν-, from Proto-Hellenic *ə-; e.g. apathetic, abiogenesis. These all stem from a PIE syllabic nasal privative *n̥-, the zero ablaut grade of the negation *ne, i.e. "n" used as a vowel, as in some English pronunciations of "button". This is the source of the 'n' in 'an-' privative ...
Example(s) a-, an-not, without (alpha privative) Greek ἀ-/ἀν-(a-/an-), not, without analgesic, apathy, anencephaly: ab-from; away from Latin abduction, abdomen: abdomin-of or relating to the abdomen: Latin abdōmen, abdomen, fat around the belly abdomen, abdominal -ac: pertaining to; one afflicted with Greek -ακός (-akós) cardiac ...
The simplest example is acrylic acid (CH 2 =CHCO 2 H). These compounds are prone to polymerization, giving rise to the large area of polyacrylate plastics. Acrylate polymers are derived from but do not contain the acrylate group. [4] The carboxyl group of acrylic acid can react with ammonia to form acrylamide, or with an alcohol to form an ...
For example, the molecules nitrostyrene and phenethylamine are quite similar; the former can even be reduced into the latter. However, nitrostyrene's α-carbon atom is adjacent to the phenyl group; in phenethylamine this same carbon atom is the β-carbon atom, as phenethylamine (being an amine rather than a styrene) counts its atoms from the ...
In organic chemistry, alpha-elimination refers to reactions of this type: [1] R 2 CHX → R 2 C: + HX. The reaction is employed to generate carbenes and nitrenes. The formation of dichlorocarbene from chloroform is an example. Alpha eliminations contrasts with beta eliminations, which are commonly used to generate alkenes: R 2 CHCXR' 2 → R 2 ...
The word "asphalt" is derived from the late Middle English, in turn from French asphalte, based on Late Latin asphalton, asphaltum, which is the latinisation of the Greek ἄσφαλτος (ásphaltos, ásphalton), a word meaning "asphalt/bitumen/pitch", [12] which perhaps derives from ἀ-, "not, without", i.e. the alpha privative, and ...