Self-ignition

The self-ignition temperature of PVF film is 390°C. The limiting oxygen iadex (LOI) for PVF is 22.6% (98), which can be raised to 30% ia antimony oxide-modified film (99). Hydrogen fluoride and a mixture of aromatic and aUphatic hydrocarbons (100) are generated from the thermal degradation of PVF. Toxicity studies, ie, survival and time to iacapacitation, of polymers, ceUulosics (101,102), and airplane iaterior materials (103) expose... 

The SAW match is similar to the safety match except that it is richer in fuel, and gives a billowing somewhat wind-resistant flame. The phosphoms sulfide [1314-85-8] in the tip provides the ignitabiUty on any soHd surface, and a Httle of the same material in the base bulb adds to wind resistance, but otherwise the base is underbalanced in active materials to prevent self-ignition from mbbing during transportation. 

Although neither inflammable nor self-igniting, sodium peroxide is highly inflammable when mixed with oxidi2able substances. Such mixtures bum violendy, even ia the absence of air. Tme sodium peroxocarbonates can be formed under the influence of atmospheric moisture and carbon dioxide. At temperatures >50° C and when exposed to pressure or friction, these peroxocarbonates can decompose and generate flame. 

Limiting oxygen index Temperature of self-ignition... 

Cbemical Reactivity - Reactivity with Water Reacts violently with liberation of heat and oxygen and the formation of caustic solution Reactivity with Common Materials Forms e qtlosive and self-igniting mixtures with wood and other combustible materials Stability During Transport Stable if kept dry Neutralizing Agents for Acids and Caustics Following the reaaion with water, the caustic solution formed can be flushed away with water and area rinsed with dilute acetic acid Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Oil spillages onto warm, absorbent materials, such as insulation, also have a limited life (see Sections 7.3.2 and 12.4.4). The oil soon decomposes to materials with a low auto-ignition temperature and self-ignites. As many insulation fires have started in this way, oil-soaked insulation should be removed without delay. Linseed oil ignites particularly easily. This has been known since at least 1925 nevertheless, in 1965 some cloths used to apply linseed oil to laboratory benches were not burned as directed but dropped into a waste bin. A fire started after a few hours and destroyed the laboratory [17J. Reference 18 lists substances that are liable to self-heat, and Reference 19 includes references to a number of incidents that have occuiTed involving substances as diverse as wood shavings, tobacco, milk powder, and soap powder. 

The antoignition temperatnre of a gas or vapor is the minimnm temperatnre at which it will ignite in air withont any external sonrce of ignition (e.g., a flame, spark, hot snrface etc.). It is often also called the spontane-ons-ignition or self-ignition temperatnre. The measnrement of AIT depends on many factors, snch as molecnlar stmctnre of the gas/vapor. 

Sokolik, A. S. 1963. Self-ignition, flame and detonation in gases. Israel Program of Scientific Translations. Jerusalem. 

Once the actual reaction begins, a defoamer can be used, but it is simpler not to overfill the reaction flask. Pressure vessels allow the use of higher temperatures and result in much shorter reaction times, simultaneously overcoming the foaming problems. After the reaction is complete and the GPC/SEC gel has been cleaned it is important not to dry the gel above 85°C as self-ignition can occur. 

Selbst-zunder, m. pyrophorus self-igniter, automatic lighter, -zundung, /. spontaneous ignition. 

Another reason to keep inventories low is the potential for storage problems. Coal in storage must be carefully handled. Improperly stored coal can oxidize (weather), causing a loss of heat content. And if heat is allowed to build up in a stagnant coal pile (or in a vessel, barge, or railcar), the coal can self-ignite. 

Self-ignition is particularly a risk with lower-grade subbituminous coals and lignite. To avoid oxidation, coal piles should be turned frequently so that heat can vent, and piles should be packed and shaped to nhninhze surface exposure. 

This hot air converts the injected fuel from an atomized liquid to a vapor to permit self-ignition (it establishes a flame front) ivithout the need for a spark plug. 

A diesel-electric locomotive uses as its prime mover a large, self-igniting, internal combustion engine of the type invented by RudolfDiesel and first successfully demonstrated in 1897. Thermal efficiency of these engines exceeded 30 percent, compared... 

Traces of acid in the product almost always degrade product stability and in some cases can lead to self-ignition and expln. The usual methods of removing traces of spent acid is by washing with water and/or dil alkali solns followed by a water wash... 

The expln temp under confinement with a heating rate of 50/mii is 190°. The self-ignition temp of a vap/air riiixt is 193°. The principle prod of the thermal decompn of NPN is carbon monoxide. The combined molar vol from one mole of NPN of carbon monoxide and carbon dioxide is 1.84 moles (at 305psi and 200°)... 

Pellets, slugs or flechettes made of U have very good powers of penetration. However, U is softer than steel so that in the process of penetrating an armored steel plate it is partially pulverized. Since in this form U is pyrophoric (self-igniting), such projectiles have an incendiary as well as a penetrating effect. According to one account of flechettes made of depleted U ... 

Historically, military pyrotechnics had rheir origin as incendiaries. The Bible refers to the use of firebrands (Judges 15 4, 5) and to the action of water on naphtha and burnt lime (II Maccabees 20—36) (I Kings 18 31—38). Such self-igniting systems were known as automatic fire (Ref 130, p 5) and culminated in Greek Fire (Vo 7j HI 17). Crucial to the further develop-... 

Hypergolic reaction systems have been proposed (Refs 46 73) for 5.56mm ammo, specifically triethylaluminum (TEA) together with inorganic oxidizers. This system is self-igniting in air, but is compatible with some nitrates, chlorates and perchlorates... 

A major review of air and water actuated (ie, self-igniting) systems was also published (Ref 24)... 

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