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A substance added to another to strengthen or otherwise alter it for the purpose of improving the performance of the finished product.
Pertaining to addition.
That property of a process in which increments of the dependent variable are independent for nonoverlapping intervals of the independent variable.



in metallurgy, a material introduced into a liquid metal to change the composition and properties of the metal or slag. A distinction is made among slag-forming additives (lime, fluorspar, and bauxite and their combinations or substituents), carbonizing additives (ground coke, cast iron, and metal carbides), oxidizing additives (ores, clinker, and metal oxides), and alloying additives (ferroalloys, hardeners, and industrial-grade chemical elements). Additives are introduced into the melting unit, ladle, or casting mold.



in petrochemistry, a substance that is added in small amounts to fuels and industrial oils to improve their working properties. Liquid fuels and oils usually do not contain more than a few hundredths or tenths of a percent additives by weight, and only certain additives are used in concentrations of about 1-2 percent or greater.

Additives in fuels improve the efficiency of combustion processes, storage life, and the ability of a fuel to maintain its original properties during shipment and use. They also reduce the harmful effects of fuels on machinery and improve performance at low temperatures. The most common additives are antiknocks, for example, tetraethyllead, which reduce detonation of engine fuels. Other widely used additives act as antioxidants (para-oxydiphenylamine and naphthol), chemical inhibitors, modifiers, metal deactivators, stabilizers, and antifouling agents.

Additives for petroleum oils and synthetic oils are classified on the basis of their use. High-viscosity additives increase the viscosity and improve the viscothermal properties of oils, while pour-point depressants lower the pour point of oils. Antioxidants protect an oil from oxidation by atmospheric oxygen; anticorrosives reduce the decay of a metal in aggressive mediums; and antiwear and antiscuff agents improve the lubricating properties of oils. Antifoaming agents reduce foam, detergents prevent deposition of solids on mechanical parts, and multipurpose additives simultaneously improve several working properties of oils. Also used as additives for oils are various hydrocarbons and compounds that consist of organic molecules and certain elements, including low-molecular surfactants and polymers.


Nefteprodukty: Svoistva, kachestvo, primenenie. Spravochnik Edited by B. V. Losikov. Moscow, 1966.
Kuliev, A. M. Khimiia i tekhnologiia prisadok k maslam i toplivam. Moscow, 1972.



A material, used in very small quantity, to modify a specific property of another material or otherwise improve its characteristics; used in paints, plasters, mortars, etc.


A function f : X -> Y is additive if

for all Z <= X f (lub Z) = lub { f z : z in Z }

(f "preserves lubs"). All additive functions defined over cpos are continuous.

("<=" is written in LaTeX as \subseteq, "lub" as \sqcup ).
References in periodicals archive ?
2008) and Bohner & Dickel (2011), future persuasion research should explore closely the potential interplay of pieces of information similar to the HSM's additivity, bias, attenuation, and contrast hypotheses instead of the controversy between dual- and single-process approaches.
Forward and backward blocking of causal judgment is enhanced by additivity of effect magnitude.
However, when they differ greatly in strength, the pattern of integration differs from additivity, yet it is not incompatible with it, according to Kubovy and van den Berg's (2008) criteria.
i]) were employed in order to determine the errors involved in implementation of the "principle of additivity.
Given these certainty conditions, Subjective Finite Additivity guarantees that any unconditional credence function will be a Kolmogorovian probability function.
Fixing any m [greater than or equal to] 8 and applying the additivity lemma in the direction of l the same way by expressing l = 8a' + b', shows that (o) holds for all m, l [greater than or equal to] 8.
dubliniensis isolates Agents Group of Interactions isolates Synergy Additivity Terbinafine FS 3.
To establish whether or not the items in the scale were of such a quality as to constitute an additive scale, Tukey's test of additivity was administered; we found that the scale had the quality of additivity (F = 25.
This conclusion is similar to that of former studies that demonstrated the superiority of additivity for PE (DOFING et al.
Sleeping Beauty, Countable Additivity, and Rational Dilemmas, JACOB ROSS
The authors made the observation that "superior efficacy was achieved with combination treatment at reduced doses without increased frequency of adverse events, suggesting that additivity for analgesia was higher than for adverse events.