Minimum oxidizer concentration

Methods of measurement. Flammability limits are determined by measuring the volume percent of a flammable gas in an oxidizing gas that will form a flammable mixture, thus identifying the lower and upper flammable limits as well as the critical oxygen concentration (the minimum oxidizer concentration that can be used to support combustion). 

There exists an oxidant concentration below which the fuel-oxidant mixture is not capable of propagating flame. This oxidant concentration is called the limit-ing/minimum oxidant concentration (LOC/MOC). LOC is dependent on the type of inert gas used. 

If chlorine does not evolve in the gas phase in normal process conditions, an inert gas flush in the reactor gas phase is recommended (see below). If a chlorine flow evolves from the liquid reaction mixture unreacted, enough inert gas flush must be provided in the reactor gas phase to lower the chlorine concentration below the minimum oxidizer concentration (MOC) of the fuel flammable range. 

Increased oxidant concentration above the minimum required for desizing increases chemical damage. 

Fujiwara et al. [94] found that, when present as a heteropolyacid complex, molybdenum(VI), germanium(IV), and silicon(IV) produced CL emission from the oxidation of luminol, and similar CL oxidation of luminol was observed for arsenic(V) and phosphorus(V) but with the addition of the metavanadate ion to the acid solution of molybdate. A hyphenated method was therefore proposed for the sensitive determination of arsenate, germanate, phosphate, and silicate, after separation by ion chromatography. The minimum detectable concentrations of arsenic(V), germanium(IV), phosphate, and silicon(IV) were 10, 50, 1, and 10... 

A minimum chromium concentration of approximately 11% is typical for stainless steel. As more chromium is added, corrosion resistance improves. Concentrations of chromium >20% are found in some alloys. Chromium addition leads to the formation of a tight-forming oxide film on the surface of the metal. This stable film is self-healing, which means that the film will reform if scratched or broken. This oxide is quite resistant to attack by acids, bases, organic compounds, and inorganic salts. 

Depth of anesthesia is determined by the concentration of anesthetic agent that reaches the brain. Brain concentration, in turn, depends on the solubility and transport of the anesthetic agent in the bloodstream and on its partial pressure in inhaled air. Anesthetic potency is usually expressed as a minimum alveolar concentration (MAC), defined as the percent concentration of anesthetic in inhaled air that results in anesthesia in 50% of patients. As shown in Table 9.6, nitrous oxide, N2O, is the least potent of the common anesthetics. Fewer than 50% of patients are immobilized by breathing an 80 20 mix of nitrous oxide and oxygen. Methoxyflurane is the most potent agent a partial pressure of only 1.2 mm Hg is sufficient to anesthetize 50% of patients, and a partial pressure of 1.4 mm Hg will anesthetize 95%. 

A minimum hydrogen concentration is not only required to minimise coke formation, but it is also important to avoid oxidation of the used catalyst [9,20], Mostly steam to hydrogen ratios of approximately 10 are used [20],... 

Iron is apt to be troublesome when present in quantities of 1 part per 100,000 and upwards. The metal oxidises, and hydrated oxide (rust) precipitates out on standing this may block the pipes conveying the water. This oxidation is assisted by certain lowly organisms known as iron bacteria.1 Iron salts are not toxic, but have a certain medicinal value and impart a bitter taste to the water. Copper salts are frequently employed to remove algae, 0-3 parts per 100,000 being about the minimum effective concentration of copper sulphate for this purpose. At such dilutions the salt is not prejudicial to the human organism. 

Stevens, W.D., W.M. Dolan, R.T. Gibbons, A. White, E.I. Eger, R.D. Miller, R.H. deJong, and R.M. Elashoff. 1975. Minimum alveolar concentration (MAC) of isoflurande with and without nitrous oxide in patients of various ages. Anesthesiology 42(2) 197-200. 

Comparison of the efficacy of inhalational agents is made by measuring the minimum alveolar concentration (MAC) in oxygen required to prevent movement in response to a standard surgical skin incision in 50% of subjects. The MAC of the volatile agent is reduced by the co-administration of nitrous oxide. 

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