Starters

C with partial decomposition. Synthesized from methanal and ammonia. Hexamine is used as starter fuel for camping stoves, as an... 

If maintenance is performed, there are two principal maintenance strategies preventive and breakdown maintenance. These are not mutually exclusive, and may be combined even in the same piece of equipment. Take for example a private motor car. The owner performs a mixture of preventive maintenance (by adding lubricating oil, topping up the battery fluid, hydraulic fluid and coolant) with breakdown maintenance (e.g. only replacing the starter motor when it fails, rather than at regular intervals). 

Strain development programs can mn into millions of doUars. This combined with the status of the strain in the overall process makes the strains extremely valuable and manufacturers rarely deposit useful cultures in one of the commercial coUections (14). Nevertheless, commercial coUections exist and are a very valuable, often used source of microorganisms that have shown some promise of producing smaU or minute quantities of products having real or possible commercial appHcations. These strains are often useful in augmenting in-house activities or as starters for a development program. 

Erom 1920 to 1931, after the expiration of the viscose patents, world output increased from 14,000 to 225,000 t per year, as more than 100 companies entered the ceUulose fiber field. In Europe, Vereinigte Glanstoff Eabriken (VGE, Germany), Enka (HoUand), I. G. Earben (Germany), Snia Viscosa (Italy), Comptoir des Textiles Artificiels (CTA, Erance), Rhodiaceta (Erance), Tubize (Belgium), and ChatiUon (Italy) were among the new starters. 

The polyalkylene glycol polymer employs a starter that consists of a relatively reactive alcohol and a smaller amount of its potassium or sodium salt. With propylene oxide, for instance, initiation of the polymeri2ation then involves the starter in the following steps ... 

Preparation of the polymer can be carried out in glass equipment at atmospheric pressure at temperatures typically above 100°C, but the higher pressures in an autoclave result in much faster reaction rates. Each polymer molecule which used butanol as a starter contains one hydroxyl end group as it comes from the reactor diol-started polymers contain two terminal hydroxyls. Whereas a variety of reactions can be carried out at this remaining hydroxyl to form esters, ethers, or urethanes, this is normally not done and therefore lubricant fluids contain at least one terminal hydroxyl group (36). 

System rehabihty is improved by providing alternative means for performing the same task. For example, automobiles were equipped with hand cranks even though they had electric starters. This back-up equipment was provided because at that time starters were unrehable. In contemporary system design, factors such as added cost, weight, and space may prohibit the use of redundant systems. 

Fermented Products. Fermented meat products such as semidried and dried sausages are generally recognized as safe, if critical points during processing are controlled properly. Some of the sausage processors use a small amount of fermented product as the starter for a new batch of product. 

A third group includes silver—nickel, silver—cadmium oxide, and silver—graphite combinations. These materials are characterized by low contact resistance, some resistance to arc erosion, and excellent non sticking characteristics. They can be considered intermediate in overall properties between silver alloys and silver or copper—refractory compositions. Silver—cadmium oxide compositions, the most popular of this class, have wide appHcation in aircraft relays, motor controllers, and line starters and controls. 

The name, number, and voltage of equipment controHed should be clearly marked on aH switch boxes, compensators, and starters. Pias and chains should be required on aH butterfly switches. Extension cords should be three-wire and limited to 8-m lengths. 

Starters. Nearly any compound having an active hydrogen can be used as starter (initiator) for the polymerization of PO. The common types are alcohols, amines, and thiols. Thus in Figure 2 ROH could be RNH2 or RSH. The fiinctionahty is derived from the starter, thus glycerol results in a triol. Some common starters are shown in Table 4. The term starter is preferred over the commonly used term initiator because the latter has a slightly different connotation in polymer chemistry. Table 5 Hsts some homopolymer and copolymer products from various starters. 

A hst of polyol producers is shown in Table 6. Each producer has a varied line of PPO and EOPO copolymers for polyurethane use. Polyols are usually produced in a semibatch mode in stainless steel autoclaves using basic catalysis. Autoclaves in use range from one gallon (3.785 L) size in research faciUties to 20,000 gallon (75.7 m ) commercial vessels. In semibatch operation, starter and catalyst are charged to the reactor and the water formed is removed under vacuum. Sometimes an intermediate is made and stored because a 30—100 dilution of starter with PO would require an extraordinary reactor to provide adequate stirring. PO and/or EO are added continuously until the desired OH No. is reached the reaction is stopped and the catalyst is removed. A uniform addition rate and temperature profile is required to keep unsaturation the same from batch to batch. The KOH catalyst can be removed by absorbent treatment (140), extraction into water (141), neutralization and/or crystallization of the salt (142—147), and ion exchange (148—150). 

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