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Fire, chemistry temperature

Another system to be mentioned here is the pseudobinary Ga203-Ti02 system. The phase relations have been determined by Kamiya and Tilley and the crystal chemistry worked out by Bursill et alf Mixtures of Ti02 and Ga203 which are titania rich produce a series of intergrowth phases when fired at temperatures above about 1400 K. These compounds have a series formula Ga4Ti 402 -2. in which m... [Pg.127]

The effect of these compounds on the sol-gel chemistry is quite complex because they affect the condensation reactions and also the final structure of the films. There are several effects that UV photoirradiation induces in the material that contains the organic residuals of sol-gel reactions. A very important one is that it affects the temperature of crystallization of the oxides such as titania the films exposed to UV light crystallize upon firing at temperatures lower than those needed for films not pretreated by UV [31]. [Pg.169]

Many people look to NFPA 2112 to fill this gap, even if they do not have a flash fire hazard, because one of the 2112 requirements measures flame resistance (per Vertical Flame, ASTM 6413) after 100 industrial launderings. While this may seem sufficient at first glance, there are two issues to consider. First, the wash method in the standard uses perfect water chemistry, temperatures, detergents, load levels, operator skills, etc. Real world laundering is often much more aggressive, and potentially detrimental to some FR technologies. Second, fabrics are submitted for... [Pg.42]

The system can prevent explosion, fire, and venting with fire under conditions of abuse. These batteries have a unique battery chemistry based on LiAsF6/l,3-di-oxolane/tributylamine electrolyte solutions which provide internal safety mechanism that protect the batteries from short-circuit, overcharge and thermal runaway upon heating to 135 °C. This behavior is due to the fact that the electrolyte solution is stable at low-to-medium temperatures but polymerizes at a temperature over 125 °C... [Pg.57]

Under poor operational conditions, tannin chemistry is a particularly forgiving form of internal treatment because it tolerates FW with significant variations in quality. It is capable of delivering clean, corrosion-free waterside surfaces in many types of boilers, despite low FW temperatures, high oxygen levels, and hardness ingress. It is especially suitable for use in smaller facilities that do not have the benefit of full-time, trained operators, and under on-off, batch process, or permanent low-fire circumstances. [Pg.409]

The importance of chemistry to the nuclear power industry is now well recognized. Chemical control in water circuits is an accepted part of the operating requirements of nuclear generating stations, as it is for modern fossil-fired stations. While there have been major advances in knowledge of the chemistry of aqueous systems at temperatures above lOQoC, there is still a need for further work. As we improve our understanding of thermodynamics and kinetics of solid-aqueous reactions and the effect of radiation on them, we can expect further advances in controlling radiation fields in reactor circuits and in minimizing iron deposition in GS plants. [Pg.328]

Where this value is known it is an excellent measure of the relative hazard of a flammable liquid. Unfortunately, it is available in only a few instances Susceptibility to Spontaneous Heating. Many materials combine with atmospheric oxygen at ordinary temperatures and liberate heat. If the heat is evolved faster than it is dissipated due to poor housekeeping, a fire can start, particularly in the presence of easily ignited waste, etc. [ Factory Mutual Modified Mackey Method, Industrial and Engineering Chemistry (March 1927)] Explosive Range or Flammability Limits. [Pg.350]

Fusion promises to provide a nearly inexhaustible supply of hydrogen fuel as well as less radioactive waste, but temperatures of fusion reactions are too high for present materials, and the huge amounts of energy needed to start fusion reactions would explode or melt any known construction materials. The fires of nuclear fusion in our Sun provided energy for early humans long before they discovered the art of combustion, see also Chemical Reactions Chemistry and Energy Explosions Fossil Fuels. [Pg.98]

Typically, a fire growth model is evaluated by comparing its calculations (predictions) of large-scale behavior to experimental HRR measurements, thermocouple temperatures, or pyrolysis front position. The overall predictive capabilities of fire growth models depend on the pyrolysis model, treatment of gas-phase fluid mechanics, turbulence, combustion chemistry, and convective/radiative heat transfer. Unless simulations are truly blind, some model calibration (adjusting various input parameters to improve agreement between model calculations and experimental data) is usually inherent in published results, so model calculations may not truly be predictions. [Pg.569]

Figures 4 and 5 present model calculations for a Montana Rosebud coal-fired, potassium carbonate seeded combustor operated under slightly fuel-rich conditions (equivalence ratio = 1.09). Note that KPO2 and KPO3 are the dominant neutral phosphorus species at all temperatures. Negative ion chemistry is dominated by PO2 and PO3 below 2000 K, phosphorus species negative ions outnumber free electrons. The only negative ion which Is comparable in concentration to PO2 is Fe02 and then only at the upper temperature range. The sharp temperature falloff of Fe02 Is caused by the stability of condensed Iron containing species. Figures 4 and 5 present model calculations for a Montana Rosebud coal-fired, potassium carbonate seeded combustor operated under slightly fuel-rich conditions (equivalence ratio = 1.09). Note that KPO2 and KPO3 are the dominant neutral phosphorus species at all temperatures. Negative ion chemistry is dominated by PO2 and PO3 below 2000 K, phosphorus species negative ions outnumber free electrons. The only negative ion which Is comparable in concentration to PO2 is Fe02 and then only at the upper temperature range. The sharp temperature falloff of Fe02 Is caused by the stability of condensed Iron containing species.

See other pages where Fire, chemistry temperature is mentioned: [Pg.452]    [Pg.476]    [Pg.190]    [Pg.83]    [Pg.516]    [Pg.358]    [Pg.721]    [Pg.354]    [Pg.63]    [Pg.21]    [Pg.540]    [Pg.58]    [Pg.66]    [Pg.350]    [Pg.5]    [Pg.92]    [Pg.93]    [Pg.174]    [Pg.69]    [Pg.45]    [Pg.103]    [Pg.1133]    [Pg.587]    [Pg.4]    [Pg.369]    [Pg.286]    [Pg.95]    [Pg.5]    [Pg.571]    [Pg.18]    [Pg.716]    [Pg.739]    [Pg.22]    [Pg.83]    [Pg.420]    [Pg.544]    [Pg.90]    [Pg.26]    [Pg.8]    [Pg.157]    [Pg.601]   
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