Chemical Formulations

By far, the largest appHcation of zinc powder is for solution purification in electrolytic zinc plants. This appHcation consumed an estimated 17,700 t of powder in 1980. Zinc powder is also used in primary batteries, frictional materials, spray metallizing, mechanical plating, and chemical formulations. 

Manufacturers and specialist materials development associations publish extensive corrosion data in the form of monographs, and this form of presentation is also used in national standards. The most recent comprehensive text in this category is perhaps the publication by the Zinc Development Association . The work is important in that the section on chemicals also deals with common, though complex, chemical formulations, e.g. Are-extinguisher fluids, soaps and syndets, agricultural chemicals such as pesticides and fertilisers. This publication also demonstrates the mammoth task of recording all the available data for just one material. A comparable book for mild steel would probably be much larger, whereas for many other materials the information has not yet been determined. Thus at best, only very incomplete data are available in this form. 

The addition and monitoring of small amounts of internal specialty polishing treatment chemical formulations... 

In addition to these products, many other specialist chemical formulations are available. For example, products may incorporate a proprietary polymer for very high silica control or blend in a carboxylate/... 

Internal treatments for BW are chemical formulations having potentially beneficial single-function, dual-function, or multifunctional effects. Globally, many thousands of BW formulations are available, and for the most part, each may be loosely classified into one or another type of commonly recognized chemical program, as described below. 

Typically, chemical formulations were supplied as balls or briquets and dispensed through bypass feeders or hanging baskets. Alternatively, pulverized or powdered treatments were dissolved in water and pumped to FW tanks or added via drip-feed arrangements. 

A wide range of polyacrylic acids (PAAs), polymethacrylic acids (PMAAs), polyacrylamides (PAMs), their salts and homo-, co-, and terpolymer derivatives are available from a great many manufacturers around the world today. Polyacrylates especially are a backbone of BW chemical formulations and are manufactured with an almost infinite variety of average molecular weights (MWs), MW distributions, activity strengths, and other characteristics. 

Any of a number of modem, polymer-based chemical formulation additives having one or more deposit-inhibiting effects when applied to water as part of a prescribed treatment program. 

Hazardous materials and an international coding system for identification. Many water treatment chemical formulations contain hazardous materials, which need special handling and transportation. 

Levodopa is a chemical formulation found in plants and animals that is converted into dopamine by nerve cells in the brain. Levodopa does cross die blood-brain barrier, and a small amount is dien converted to dopamine. This allows the drug to have a pharmacologic effect in patients witii Parkinson s disease (Pig. 29-1). Combining levodopa witii another drug (carbidopa) causes more levodopa to reach die brain. When more levodopa is available, the dosage of levodopa may be reduced. Carbidopa has no effect when given alone. Sinemet is a combination of carbidopa and levodopa and is available in several combinations (eg, Sinemet 10/100 has 10 mg of carbidopa and 100 mg of levodopa Sinemet CR is a time-released version of die combined drugs). 

EPA. 1989d. Pesticide chemicals. Formulating and packing subcategory. U.S. Environmental Protection Agency. Code of Federal Regulations. 40 CER 455. 

Table 12.15 Chemical formulation for one-bath salt variant A[158]... 

To determine the suitability of fluorinated HDPE containers as packaging material for the solvent-based formulations, the containers were placed in well-ventilated ovens at 50°C for 28 days. During this period the mass loss of the contents was monitored. To date more than 130 liquid crop protection chemical formulations have been evaluated at the AEC by this method with at least 91 of them having serious permeation problems through the untreated HDPE containers. In only two cases fluorinated containers did not have acceptable barrier properties. 

Toxicity of 2,4-D to animals and nontarget plant species is far less clear-cut. It is slightly toxic to wildfowl (e.g., quail and mallard ducks) and moderately toxic to some other bird species. The toxicity of the chemical to aquatic life varies both by chemical formulation and by animal species, though it is clearly toxic to many species, including stream trout, earthworms, and beneficial insects. 2,4-D has been shown to cause genetic damage in crops including barley, wheat, rice, and onions and can also increase the severity of some plant diseases. ... 

The range of economic products necessary for managing the contemporary lawn is mind-boggling. The economy includes, but is by no means restricted to, power and nonpower tool makers, seed growers, turf farms, raw chemical producers and chemical formulators, the retail outlets that supply many of these goods, the global workshops that produce them, and the offices that imagine, execute, and advertise their diverse forms. 

Long before the advent of professional applicators and the formation of a youth chemical work force, most homeowners dealt directly with local retailers. Perceiving a problem with their lawn, homeowners might approach a garden supply or hardware store owner or employee, describe the conditions they see, and leave the store with the product recommended by the local expert. The companies that supplied chemical formulations to these retailers-the formulator firms who buy, mix, and brand chemical combinations-were largely hidden from... 

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