Variety of formulations

Poly etrafluoroethylene is manufactured and sold in three forms granular, fine powder, and aqueous dispersion each requires a different fabrication technique. Granular resins are manufactured in a wide variety of grades to obtain a different balance between powder flows and end use properties (Pig. 1). Pine powders that are made by coagulating aqueous dispersions also are available in various grades. Differences in fine powder grades correspond to their usefulness in specific appHcations and to the ease of fabrication. Aqueous dispersions are sold in latex form and are available in different grades. A variety of formulation techniques are used to tailor these dispersions for specific appHcations. 

Mecli2ine is often used for the therapy of motion sickness and is available without prescription in a variety of formulations. 

The diversity of radionucHde half-life and chemical nature of commonly used radiopharmaceuticals demands a variety of formulation matrices, packaging containers, and storage conditions. The containers, ingredients, and processes used in these products must meet the stringent requirements for parenteral pharmaceuticals, as well as provide safe conditions for storage, handling, and disposal of the radioactive material. 

Because of this interaction, PVP has found appHcation in surfactant formulations, where it functions as a steric stabilizer for example to generate uniform particle-size polystyrene emulsions (110—112). In a variety of formulations, a surfactant s abiHty to emulsify is augmented by PVP s abiHty to stabilize coUoids stericaHy and to control rheology. 

The wide variety of formulations and manufacturing processes available allows the designer to achieve the lowest possible cost for a product, often the lowest cost of any available construction material. 

Urethane Liquid Exceptional abrasion, cut, and tear resistance. Poor moisture and heat resistance. Variety of formulations leading to different properties including range of durometers without plasticizers. Antistatic rollers and tires, hose for transfer of flammables, strain gages, pressure transducers. 

The final authority on the durability of catalysts is performance in road vehicles. Such data have been rapidly accumulated by the various automobile manufacturers in recent months. This data takes into consideration all the accidents of everyday usage, serving to test how much abuse the catalyst can withstand and still perform its duty. Experience has shown that fresh oxidation and reduction catalysts by a large variety of formulations from many manufacturers would indeed perform their duty. Many oxidation catalysts perform well enough at 25,000 accumulated miles to satisfy the requirement of 0.41 g hydrocarbon/mile and 3.4 g CO/mile, but few would perform well enough at 50,000 miles without maintenance and adjustment of the engine. Many such vehicle endurance tests have to be terminated because of malfunction of the engine or the auxiliary equipment. 

A variety of formulations exist for cleaning organics from burners and other fireside areas. Soot, oil, and grease removers are widely available the formulations are often very specific and can be produced in both aqueous and nonaqueous solvent bases. Nonaqueous solvents commonly include petroleum spirit, naphtha, or odorless kerosene. 

Advantages of secondary alkanesulfonates which recommend them for a great variety of formulations are the following ... 

Transdermal nicotine is available in a variety of formulations and dosing schedules (e.g., 15 mg/l6 hours 7, 14, and 21 mg/24 hours and 11 and 22 mg/ 24 hours) (Cinciprinni and McClure 1998). Peak nicotine concentrations for the various systems are reached 2-6 hours after application, and steady state conditions occur 2—3 days after continued patch use (Henningfield 1995). The highest-dose patch (i.e., 21 or 22 mg/24 hours or 15 mg/l6 hours) delivers approximately 0.9 mg of nicotine per hour transdermally (Henningfield... 

An alternative to the traditional approach is to generate the electronic states as needed during the dynamics. This has been done for atomic collisions, where detailed calculations and comparisons with experimental results are possi-ble.(4-8) General treatments of the coupling of electronic and nuclear motions in molecular systems can be done in a variety of formulations. In particular, Ohrn, Deumens and collaborators have implemented a general variational treatment in... 

A variety of formulations of salicylic acid have been used as peeling agents. These include 50% ointment formulations (Table 6.1) [2,3], as well as 10, 20 and 30% ethanol formulations (Table 6.2) [4,6]. More recently, commercial formulations of salicylic acid have become available (BioGlan Pharmaceuticals Company, Malvern, PA Bionet Esthetics, Little Rock, AR). 

The past decade has seen a dramatic increase in the number of reported applications of neural computing in pharmaceutical formulation [29-32]. Applications now cover a variety of formulations—for example, immediate and controlled release tablets, skin creams, hydrogel ointments, liposomes and emulsions, and film coatings. The following examples are by no means exhaustive, but they show where neural computing has been used successfully in modeling formulations. 

Propargylalcohol has been found to be active in corrosion control, and a variety of formulations with propargylalcohol have been proposed. A condensate of a polyamine, such as diethylenetriamine, triethylenetetramine, or... 

Franz et al. [42] reviewed these techniques completely, along with statistical screening techniques and other experimental methods, with an excellent list of publications. A few selected publications from the recent literature demonstrate the wide variety of formulation and processing problems to which these techniques can be applied and the varying methods selected for optimization. 

Technical chlordane is an organochlorine compound first introduced into the United States in 1947 in a variety of formulations for use as a broad-spectrum pesticide. By 1974, about 9.5 million kg of chlordane were being produced annually. Concern over the potential carcinogenicity of chlordane has led to sharply curtailed production. Since 1983, chlordane use in the United States has been prohibited, except for control of underground termites. 

Pyrethrum refers to the oleoresin extracted from the dried flowers of Tanacetum cinerariaefolium (Asteraceae) and is the source of the pyrethrins, chrysanthemates and pyrethrates. Among the natural pyrethrins, those incorporating the alcohol pyrethrolone, namely pyrethrins 1 and II (Fig. 9), are the most abundant and account for most of the insecticidal activity. The pyrethrins are recommended for control of a wide range of insects and mites on fruit, vegetables, field crops, ornamentals, glasshouse crops and house plants, as well as in public health, stored products, animal houses and on domestic and farm animals. Pyrethrins are sold in a wide variety of formulations, under many different trade names by a large number of different manufacturers. 

Ephedra (ma huang) is a popular botanical incorporated into a variety of formulations for weight loss, energy or performance enhancement, and symptomatic control of asthma. A pharmacodynamic interaction leading to a fatality has been reported with concurrent use of caffeine and ephedra (62), possibly as a result of additive adrenergic agonist effect of the ephedrine alkaloids and caffeine on the cardiovascular system and the CNS (63). Ephedra was recently withdrawn from the market (64). 

The visual observation of the dissolution of a dosage form can quickly provide an indication of problems with the formulation or the dissolution test conditions without the requirement for sample analysis. This is particularly useful in the early stages of formulation and method development, when a variety of formulations or a range of dissolution media may be under consideration. 

Milk protein products. As indicated in Table 1, the food industry is placing major emphasis on the production and utilization of milk protein products in a wide variety of formulated food products (20,21,22). Although nonfat dry milk (NFDM) and whey powder are major milk protein ingredients in formulated foods, casein and whey protein concentrates, which contain their proteins in a more highly concentrated and functional form, are essential for certain food product applications, such as those products that require the proteins as an emulsifier agent. Additional details on the processing methods and conditions used to produce the various milk protein products are available (23). 

Modern technological practice, particularly the various types of chemical processing, use a great variety of formulations for the synthesis of polyurethanes. Therefore it is nearly impossible to create a general kinetic model which would be valid for various polymerizing systems. However, the same general approach to creating such models can be used for different cases. Therefore, it is useful to demonstrate the method used to construct a model and its characteristic kinetic equations for some typical cases. 

Another vehicle for the ex vivo delivery of ribozyme genes is cationic lipids (Hope et al., 1998). Since there are a variety of formulations for these lipids, it is usually best to test a panel of lipids for those that provide the highest efficiency of gene transfer with the least toxicity. 

The interfacial tension is a key property for describing the formation of emulsions and microemulsions (Aveyard et al., 1990), including those in supercritical fluids (da Rocha et al., 1999), as shown in Figure 8.3, where the v-axis represents a variety of formulation variables. A minimum in y is observed at the phase inversion point where the system is balanced with respect to the partitioning of the surfactant between the phases. Here, a middle-phase emulsion is present in equilibrium with excess C02-rich (top) and aqueous-rich (bottom) phases. Upon changing any of the formulation variables away from this point—for example, the hydrophilie/C02-philic balance (HCB) in the surfactant structure—the surfactant will migrate toward one of the phases. This phase usually becomes the external phase, according to the Bancroft rule. For example, a surfactant with a low HCB, such as PFPE COO NH4+ (2500 g/mol), favors the upper C02 phase and forms w/c microemulsions with an excess water phase. Likewise, a shift in formulation variable to the left would drive the surfactant toward water to form a c/w emulsion. Studies of y versus HCB for block copolymers of propylene oxide, and ethylene oxide, and polydimethylsiloxane (PDMS) and ethylene oxide, have been used to understand microemulsion and emulsion formation, curvature, and stability (da Rocha et al., 1999). 

The last half of this book includes an extensive listing of gas chromatographic methods used to analyze pharmaceuticals and excipients in a wide variety of formulations. Additional applications are listed in Table 4.5. 

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