Links handling

The properties required by jet engines are linked to the combustion process particular to aviation engines. They must have an excellent cold behavior down to -50°C, a chemical composition which results in a low radiation flame that avoids carbon deposition on the walls, a low level of contaminants such as sediment, water and gums, in order to avoid problems during the airport storage and handling phase. 

Telecommunications systems will include internal communications within the platforms (telephone, radio, walkie-talkie, air-ground-air, navigation, public address) and external systems (telephone, telex, fax, telemetry, VFIF radio, and possibly satellite links). These systems are designed to handle the day-to-day communications as well as emergency situations. 

These tests generate several Gigabytes of data that are fed into a historical database. Although most of the analysis is performed automatically, human interaction is still needed to compare current and past data. Data are stored on optical CD S s from which the historical data bank are retrieved during field inspections from a mobile unit. Each of these is equipped with a CD-jukebox linked to an analysis station. The jukebox can handle 100 CD s, enough to store all previously recorded data. A dedicated software pre-fetches the historical data and compares it on-line with the newly acquired NDT-data. It is based on fuzzy algorithms applied to signal features. 

Rocket Propellants. SoHd rocket propellants are mostly based on chemically cross-linked polymeric elastomers to provide the mechanical properties required in launchings and the environmental conditions experienced in storage, shipment, and handling (see Elastomers, synthetic). Double-and triple-based nitrocellulose propellants are also employed as rocket propellants. 

Most peroxides of the appropriate thermal stabiUty for mbber cross-linking are Hquids or low melting soHds which, in addition to the 100% active product, are offered adsorbed on inert, free-flowing carriers or in polymeric master batches for easy handling. Peroxides (qv) are oxidizing materials and should be stored away from other mbber chemicals and kept away from heat sources. 

Starch derivatives are also used to encapsulate pesticides (qv) in a cross-linked starch—xanthate to improve safety in handling and reduce water leaching losses (51,52). Littie or no pesticide is lost during drying. The encapsulated formulations have excellent shelf life when dry, but when placed in water or soil the pesticide is readily released. 

A variety of specialized idlers are available. Examples are plastic disk catenary idlers for handling wet corrosive materials two roU idlers, where the roUs are oriented in a vee for lighter duty conveying system and suspended idler supports for severe service. In this last type, three to five idler roUs are linked end-to-end and suspended from conveyor frame stringers to form a catemary that cradles the belt. 

In order to "cure" or "vulcanize" an elastomer, ie, cross-link the macromolecular chains (Fig. 2), certain chemical ingredients are mixed or compounded with the mbber, depending on its nature (4,5). The mixing process depends on the type of elastomer a high viscosity type, eg, natural mbber, requires powerhil mixers (such as the Banbury type or mbber mills), while the more Hquid polymers can be handled by ordinary rotary mixers, etc (see Rubber... 

FIG. 12-73 Link-Belt Roto-Louvre dryer. (Material Handling Systems Division, FMC Corp.)... 

Some niekel eompounds may be irritant to skin and eyes and dermal eontaet with niekel ean result in allergie eontaet dermatitis. Niekel earbonyl is extremely toxie by inhalation and should be handled in totally enelosed systems or with extremely effieient ventilation. Air monitors linked to alarms may be required to deteet leaks. Respiratory equipment must be available for dealing with leaks. Biologieal eheeks (e.g. niekel in urine) should be eonsidered for routine operations involving niekel eatalysts. 

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