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Additive Character
Additive may refer to: Mathematics * Additive function, a function in number theory * Additive map, a function that preserves the addition operation * Additive set-functionn see Sigma additivity * Additive category, a preadditive category with finite biproducts * Additive inverse, an arithmetic concept Science * Additive color, as opposed to subtractive color * Additive model, a statistical regression model * Additive synthesis, an audio synthesis technique * Additive genetic effects * Additive quantity, a physical quantity that is additive for subsystems; see Intensive and extensive properties Engineering * Feed additive * Gasoline additive, a substance used to improve the performance of a fuel, lower emissions or clean the engine * Oil additive, a substance used to improve the performance of a lubricant * Weakly additive, the quality of preferences in some logistics problems * Polymer additive * Pit additive, a material aiming to reduce fecal sludge build-up and control odor i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Additive Function
In number theory, an additive function is an arithmetic function ''f''(''n'') of the positive integer variable ''n'' such that whenever ''a'' and ''b'' are coprime, the function applied to the product ''ab'' is the sum of the values of the function applied to ''a'' and ''b'':Erdös, P., and M. Kac. On the Gaussian Law of Errors in the Theory of Additive Functions. Proc Natl Acad Sci USA. 1939 April; 25(4): 206–207online/ref> f(a b) = f(a) + f(b). Completely additive An additive function ''f''(''n'') is said to be completely additive if f(a b) = f(a) + f(b) holds ''for all'' positive integers ''a'' and ''b'', even when they are not coprime. Totally additive is also used in this sense by analogy with totally multiplicative functions. If ''f'' is a completely additive function then ''f''(1) = 0. Every completely additive function is additive, but not vice versa. Examples Examples of arithmetic functions which are completely additive are: * The restriction of the Logarithm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feed Additive
A feed additive is an additive of extra nutrient or drug for livestock. Such additives include vitamins, amino acids, fatty acids, minerals, pharmaceutical, fungal products and steroidal compounds. The additives might impact feed presentation, hygiene, digestibility, or effect on intestinal health.Merck Manual October 201Nutritional Requirements of Beef CattlePage accessed March 18, 2015 Examples Amino acids Methionine, lysine, and tryptophan are commonly deficient in animal diets, so these amino acids are added to feed. In the case of methionine, 2-Hydroxy-4-(methylthio)butyric acid is often use in the place of methionine. "Minerals" Several elements enhance the growth characteristics of animals. Elements themselves are rarely used as additives but derivatives thereof. Ethylenediamine dihydroiodide (EDDI) is added to pet food and cattle feed to prevent iodine deficiency. A controversial additive is arsenic, often supplied in the form of the organoarsenic compound called roxar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Food Additive
Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (salting), smoke (smoking), sugar (crystallization), etc. This allows for longer-lasting foods such as bacon, sweets or wines. With the advent of processed foods in the second half of the twentieth century, many additives have been introduced, of both natural and artificial origin. Food additives also include substances that may be introduced to food indirectly (called "indirect additives") in the manufacturing process, through packaging, or during storage or transport. Numbering To regulate these additives and inform consumers, each additive is assigned a unique number called an "E number", which is used in Europe for all approved additives. This numbering scheme has now been adopted and extended by the '' Codex Alimentarius'' Commission to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biodegradable Additives
Biodegradable additives are additives that enhance the biodegradation of polymers by allowing microorganisms to utilize the carbon within the polymer chain as a source of energy. Biodegradable additives attract microorganisms to the polymer through quorum sensing after biofilm creation on the plastic product. Additives are generally in masterbatch formation that use carrier resins such as polyethylene (PE), polypropylene (PP), polystyrene (PS) or polyethylene terephthalate (PET). Most common synthetic plastics are not biodegradable, and both chemical and physical properties of plastics play important roles in the process of plastic degradation. The addition of biodegradable additives can influence the mechanism of plastic degradation by changing the chemical and physical properties of plastics to increase the rate of degradation. Biodegradable additives can convert the plastic degradation process to one of biodegradation. Instead of being degraded simply by environmental factors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pit Additive
Pit additives is a commercially-produced material that aims to reduce fecal sludge build-up and control odor in pit latrines, septic tanks and wastewater treatment plants. Manufacturers claim to use effective microorganisms (EM) in their products. Current scientific evidence does not back up most claims made by manufacturers about the benefits. Removing sludge continues to be a problem in pit latrines and septic tanks. Background Pit additives are advocated for use in sanitation systems like pit latrines and septic tanks. Additives consist of packages of micro-organisms or enzymes or both. More than 1,200 septic system additives were estimated to be available in the U.S. in 2011. However, very little peer-reviewed and replicated field research exists to confirm the efficacy of biological additives. Claimed benefits Pit additive claims include an increase in speed of the breakdown of sludge, which may also decrease odor. The claim is based on assertions that the additive cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer Additive
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive to produce, has led to its widespread use. Plastics typically are made through human industrial systems. Most modern plastics are derived from fossil fuel-based chemicals like natural gas or petroleum; however, recent industrial methods use variants made from renewable materials, such as corn or cotton derivatives. 9.2 billion tonnes of plastic are estimated to have been made between 1950 and 2017. More than half this plastic has been produced since 2004. In 2020, 400 million tonnes of plastic were produced. If global trends on plastic demand continue, it is estimated that by 2050 annual global plastic production will reach over 1,10 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weakly Additive
In fair division, a topic in economics, a preference relation is weakly additive if the following condition is met: : If A is preferred to B, and C is preferred to D (and the contents of A and C do not overlap) then A together with C is preferable to B together with D. Every additive utility function is weakly-additive. However, additivity is applicable only to cardinal utility functions, while weak additivity is applicable to ordinal utility functions. Weak additivity is often a realistic assumption when dividing up goods between claimants, and simplifies the mathematics of certain fair division problems considerably. Some procedures in fair division do not need the value of goods to be additive and only require weak additivity. In particular the adjusted winner procedure only requires weak additivity. Cases where weak additivity fails Case where the assumptions might fail would be either *The value of A and C together is the less than the sum of their values. For instance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Additive
Oil additives are chemical compounds that improve the lubricant performance of base oil (or oil "base stock"). The manufacturer of many different oils can utilize the same base stock for each formulation and can choose different additives for each specific application. Additives comprise up to 5% by weight of some oils.Thorsten Bartels et al. "Lubricants and Lubrication" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Weinheim. Nearly all commercial motor oils contain additives, whether the oils are synthetic or petroleum based. Essentially, only the American Petroleum Institute (API) Service SA motor oils have no additives, and they are therefore incapable of protecting modern engines. The choice of additives is determined by the application, e.g. the oil for a diesel engine with direct injection in a pickup truck (API Service CJ-4) has different additives than the oil used in a small gasoline-powered outboard motor on a boat (2-cycle engine oil). Types of additives O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gasoline Additive
Petrol additives increase petrol's octane rating or act as corrosion inhibitors or lubricants, thus allowing the use of higher compression ratios for greater efficiency and power. Types of additives include metal deactivators, corrosion inhibitors, oxygenates and antioxidants. Some additives are harmful and are regulated or banned in some countries. Additives *Oxygenates ** Alcohols: *** Methanol (MeOH) *** Ethanol (EtOH); see also common ethanol fuel mixtures *** Isopropyl alcohol (IPA) *** ''n''-butanol (BuOH) *** Gasoline grade ''t''-butanol (GTBA) ** Ethers: *** Methyl tert-butyl ether (MTBE), now outlawed in many states of the U.S. for road use because of water contamination. *** Tertiary amyl methyl ether (TAME) *** Tertiary hexyl methyl ether (THEME) *** Ethyl tertiary butyl ether (ETBE) *** Tertiary amyl ethyl ether (TAEE) *** Diisopropyl ether (DIPE) * Antioxidants, stabilizers ** Butylated hydroxytoluene (BHT) ** 2,4-Dimethyl-6-tert-butylphenol ** 2,6-Di-tert-butylphe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intensive And Extensive Properties
Physical properties of materials and systems can often be categorized as being either intensive or extensive, according to how the property changes when the size (or extent) of the system changes. According to IUPAC, an intensive quantity is one whose magnitude is independent of the size of the system, whereas an extensive quantity is one whose magnitude is additive for subsystems. The terms ''intensive and extensive quantities'' were introduced into physics by German writer Georg Helm in 1898, and by American physicist and chemist Richard C. Tolman in 1917. An intensive property does not depend on the system size or the amount of material in the system. It is not necessarily homogeneously distributed in space; it can vary from place to place in a body of matter and radiation. Examples of intensive properties include temperature, ''T''; refractive index, ''n''; density, ''ρ''; and hardness, ''η''. By contrast, extensive properties such as the mass, volume and entropy of syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Additive Map
In algebra, an additive map, Z-linear map or additive function is a function f that preserves the addition operation: f(x + y) = f(x) + f(y) for every pair of elements x and y in the domain of f. For example, any linear map is additive. When the domain is the real numbers, this is Cauchy's functional equation. For a specific case of this definition, see additive polynomial. More formally, an additive map is a \Z-module homomorphism. Since an abelian group is a \Z-module, it may be defined as a group homomorphism between abelian groups. A map V \times W \to X that is additive in each of two arguments separately is called a bi-additive map or a \Z-bilinear map. Examples Typical examples include maps between rings, vector spaces, or modules that preserve the additive group. An additive map does not necessarily preserve any other structure of the object; for example, the product operation of a ring. If f and g are additive maps, then the map f + g (defined pointwise) is additiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Additive Genetic Effects
Additive genetic effects occur when two or more genes source a single contribution to the final phenotype, or when alleles of a single gene (in heterozygotes) combine so that their combined effects equal the sum of their individual effects. Non-additive genetic effects involve dominance (of alleles at a single locus) or epistasis (of alleles at different loci). See also * Quantitative genetics Quantitative genetics deals with phenotypes that vary continuously (such as height or mass)—as opposed to discretely identifiable phenotypes and gene-products (such as eye-colour, or the presence of a particular biochemical). Both branches u ... References Genetics {{Genetics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
