Flame particles

VO the most difficult to burn, extinguished after 10 s, neither dripping nor flaming particles. 

V2 extinguished after 30 s, flaming particles or drips permitted. 

The resulting explosion shatters the projectile body and disperses WP. Contact with the air ignites spontaneously WP, producing dense white smoke and flaming particles. Muzzle velocity 2500fps and max range 19910... 

Possible applications of laser enhanced ionization in flame diagnostics are 1. simultaneous observation of ionization and fluorescence signals from various levels might provide more information on the sequence of processes leading to and from the ionization continuum 2. the measurement of ion mobilities, relating to cross-sections for elastic collisions between ions and flame particles 3. measurement of ionization rate constants relating to cross-sections for inelastic collisions between excited atoms and other flame particles 4. measurement of recombination rate constants, relating to cross-sections for inelastic collisions between ions, electrons and neutrals. 

There are a number of different 94 V classifications, the best being 94 V-0. To pass this requirement, none of the individual burn times can be greater than 10 s and the total of the 10 burn times must be less than 50 s. There are a number of other requirements for this rating none of the specimens may bum up to the clamp, none may drip flaming particles that ignite cotton-wool placed under the specimen and for the second flames the total of the bum time and afterglow cannot exceed 30 s. 

Whether or not specimens drip flaming particles that ignite the cotton. 

Openings in enclosures tops, sides, and bottoms shall comply with the dimensional requirements of the relevant product or machine standards. The restrictions are necessary to prevent objects from entering the product via top or sides and prevent in the event of fire, flaming particles from exiting the bottom of the enclosure. Examples of enclosure opening sizes are ... 

The combustion of an organic material proceeds, however, with concomitant phenomena which may increase the fire hazard. The most important of these are smoke formation and escaping combustion gases. A particular risk of burning thermoplastics is that dripping hot or flaming particles may occur. 

Burning stops within 30 seconds on a vertical specimen drips of flaming particles are allowed. 

Fig. 20.25 Rame spray pyrolysis (FSP) apparatus for producing ceramic nanoparticles and directly depositing them on a cooled substrate positioned above the flame. Particles arc simultaneously collected downstretun on a fiber filter for comparison (Reprinted with permission from Madler et al. 2006b, Copyright 2006 Elsevier)...

Fumed Silica. A pure colloidal form of silica produced by reacting silicon tetrachloride in a flame. Particle size is some 12nm, and BET surface area 230 m2/g.(Tradenames include Cab-O-Sil M5 and Degussa OX-50). 

V-0 Specimens must extinguish within 10 seconds after each flame application (see Fig. 8.12) and a total combustion of less than 50 seconds after 10 flame applications. No samples are to drip flaming particles or have glowing combustion lasting beyond 30 seconds after the second flame test. 

UL-94-V-2 Specimens must extinguish within 30 sec. after each flame application and within a total of less than 250 sec. after a total of 10 flame applications. Samples may drip flaming particles or burn briefly, but no specimen may exhibit glowing combustion that lasts for more than 60 sec. after the second flame test. 

V2 as for VI, but flaming particles may occur that ignite the surgical cotton. 

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