Control agents

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Dust control Dust control agent Dusts... 

Statexan ITA Static control agents Static decay Static decay times Static dissipation Static drying Static electricity Static eliminating devices Static mixers Static phenomena... 

Fluoroacetic acid [144-49-OJ, FCH2COOH, is noted for its high, toxicity to animals, including humans. It is sold in the form of its sodium salt as a rodenticide and general mammalian pest control agent. The acid has mp, 33°C bp, 165°C heat of combustion, —715.8 kJ/mol( —171.08 kcal/mol) (1) enthalpy of vaporization, 83.89 kJ /mol (20.05 kcal/mol) (2). Some thermodynamic and transport properties of its aqueous solutions have been pubHshed (3), as has the molecular stmcture of the acid as deterrnined by microwave spectroscopy (4). Although first prepared in 1896 (5), its unusual toxicity was not pubhshed until 50 years later (6). The acid is the toxic constituent of a South African plant Dichapetalum i mosum better known as gifirlaar (7). At least 24 other poisonous plant species are known to contain it (8). 

Environmental Applications. Hydrogen peroxide is an ecologically desirable poUution-control agent because it yields only water or oxygen on decomposition. It has been used in increasingly greater amounts to convert domestic and industrial effluents to an environmentally compatible state... 

Health and Safety. The U.S. FDA has affirmed R%- and S(—)-maHc acid as substances that are generally recognized as safe (GRAS) as flavor enhancers, flavoring agents and adjuvants, and as pH control agents at levels ranging from 6.9% for hard candy to 0.7% for miscellaneous food uses (42). R%- and A(—)-maHc acid may not be used in baby foods. MaHc acid is also cleared to correct natural acid deficiencies in juice or wine (43). 

Chemical suppHers include basic manufacturers of active ingredients, formulators, and distribution or service industries. The relative importance of each depends greatly upon the industry being suppHed. In many instances, the vendor may supply a number of performance chemicals (eg, corrosion control agents or stabilizers) in addition to the antimicrobial agent. 

Basic Components. The principal components in emulsion polymerization are deionized water, monomer, initiator, emulsifier, buffer, and chain-transfer agent. A typical formula consists of 20—60% monomer, 2—10 wt % emulsifier on monomer, 0.1—1.0 wt % initiator on monomer, 0.1—1.0 wt % chain-transfer agent on monomer, various small amounts of buffers and bacteria control agents, and the balance deionized water. 

Production and Utilization. The most important potential use for scleroglucan is as a mobiUty control agent for enhanced oil recovery. 

Injected formulation of leuptoleine and triptoreline [57773-63 ] ate used to treat metastasized cancer of the prostrate, whereas an encapsulated formulation of bromocryptin [25614-03-3] is used to inhibit milk production in women after pregnancy. The performance of encapsulated hormonal polypeptides is weU documented (47). Injectable biodegradable mictocapsules loaded with fertUity control agents have been under development for a number of years and have been carried to various stages of clinical development (48) (see Contraceptives). 

Foam-control agents commonly are employed (see Defoamers). 

E. R. Hah and. W. Barry, eds., Biorational Pest Control Agents Formulation and Delivery, ACS Symposium Series No. 595, American Chemical Society, Washington, D.C., 1995, 320 pp. 

Water-Based Muds. About 85% of all drilling fluids are water-based systems. The types depend on the composition of the water phase (pH, ionic content, etc), viscosity builders (clays or polymers), and rheological control agents (deflocculants or dispersants (qv)). 

Lignite, generally leonardite, and lignite derivatives are appHed in water-based muds as thinners and filtration control agents. Leonardite is an oxidized lignite having a high content of humic acids, which may be described as carboxylated phenoHc polymers (59,60). Litde is known about the chemical stmcture. 

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