Air generators

Chloroform was formerly used in medicine as an anaesthetic. One disadvantage for this purpose is the ready oxidation which chloroform undergoes on exposure to light and air, generating the poisonous phosgene, or carbonyl chloride, COCU- This is counteracted by storing the liquid in dark amber-... 

The discovery that usehil chemicals could be made from coal tar provided the foundation upon which the modem chemical industry is built. Industrial chemistry expanded rapidly in the late nineteenth century in German laboratories and factories where coal-tar chemicals were refined and used in synthesis of dyes and pharmaceuticals. But coal-tar production has an eadier origin, dating back to the discovery by William Murdock in 1792 that heating coal in the absence of air generated a gas suitable for lighting. Murdock commercialized this technology, and by 1812 the streets of London were illuminated with coal gas (1). 

Fig. 7. Plant for spray-drying of detergents and soaps. 1, Burner 2, air combustion 3, cold air fan 4, hot air generator 5, spray-drying tower 6, cleaning ring 7, no22les circuit 8, tower suction cyclones group 9, tower suction fan 10, double-flap dischargers 11, recovery powder cyclone 12, recovery powder fan 13, belt conveyor 14, air lift 15, air lift suction cyclones 16, air lift suction fan 17, double-flip dischargers 18, vibrating sieve.

The fan drive components are less accessible for maintenance, which may have to be done in the hot air generated by natural convection. 

Characteristics of the air jet in the room might be influenced by reverse flows, created by the jet entraining the ambient air. This air jet is called a confined jet. If the temperature of the supplied air is equal to the temperature of the ambient room air, the jet is an isothermal jet. A jet with an initial temperature different from the temperature of the ambient air is called a nonisother-mal jet. The air temperature differential between supplied and ambient room air generates buoyancy forces in the jet, affecting the trajectory of the jet, the location at which the jet attaches and separates from the ceiling/floor, and the throw of the jet. The significance of these effects depends on the relative strength of the thermal buoyancy and inertial forces (characterized by the Archimedes number). 

Acid fumes Particles in the air generated by the condensation of acid vapors. They may also arise from sublimation, condensation, or chemical reaction. 

Cool inlet air is desirable. For every 5°F of ambient air temperature reduction, the volume of compressed air generated increases by 1 per cent with the same power consumption. This increase in performance is due to the greater density of the intake air. 

It usually ignites when poured in air (generating an extended liquid/air interface). This ignition is remarkable in a compound containing over 89% of bromine. 

When a flame occurs there is started a current of air generated thereby. This draft serves to maintain and to increase the flame. The fire destroys without intermission the air which supports it and would produce a vacuum, if other air could not come to supply it. So soon as the air is no longer in condition to sustain a flame, no earthly crea ture can live in it any more than can the flame. 87... 

SMOKE. A colloidal or microscopic dispersion of a solid in gas, and aerosol. (1) Coal smoke A suspension of carbon particles in hydrocarbon gases or in air, generated by combustion. The larger particles can be removed by electrostatic precipitation in the stack (Cottrell). Dark color, nausealing odor,... 

Calcination. After crystallization, the solid contains a substantial amount of organic base which must be removed to give the catalytically active material. The removal can be achieved only by decomposition, and calcination is the most common process used. But calcination at temperatures insufficient to bum all the organic or in-static air generates less active catalysts (Martens et al., 1993). On the other hand, calcination without temperature control can cause the sudden combustion of the organic material, and, at the high temperatures that are reached, the Tilv separates from the crystalline structure to form Ti02. 

Potassium superoxide, K02, is a particularly valuable compound because of its use in spacecraft and in self-contained breathing devices to remove moisture and C02 from exhaled air, generating oxygen in the process ... 

H. Schillinger, R. Sauerbrey, Electrical conductivity of long plasma channels in air generated by self-guided femtosecond laser pulses, Applied Physics B 68, 753 (1999)... 

I hope not. It has taken me months to perfect. I am simply trying to measure the quantities of air generated by distillation of plant matter. ... 

Citrus seed oil, another byproduct in citrus industry, is required to have high stability for cooking purposes. Citrus seed oil is subject to oxidative changes because of the presence of a high percentage of unsaturated fatty acids. The oil is readily oxidized in the presence of air, generating hydroperoxides, alcohols, aldehydes, ketones, hydrocarbons, and carboxylic acids as the primary, secondary, and tertiary oxidized products, respectively. 

Phosphorus or metalic sodium burn in the air generating dense white smoke. The principle of smoke production is the same as the above. The reaction may occur as follows ... 

The zero-air purge gas is prepared with an AADCO 737A zero-air generator and is stored in 35-L stainless steel containers at 400 psi. Zero air was chosen because helium will not cryocondense in the sample cans at liquid N2 temperatures, and commercial prepurified N2 contains too much con-... 

An alkali metal bead, usually rubidium sulfate, is positioned above the jet in NPD, as seen in Fig. 2, and the current is applied to this bead, which causes it to achieve temperatures up to 800°C. The addition of hydrogen and air generates plasma around the bead, and carrier gas containing the solutes is delivered to the tip of the jet and the plasma. Specific ions are produced in the plasma from nitrogen- or phosphorus-containing compounds. These ions move to the charged collector. This movement of ions generates a current that is measured... 

Conventional mining is both of historical interest and is still used to produce nearly a quarter of the world s sulfur (Table 9.2). Mining brings to the surface lumps of either a volcanic or one of the many pyritic forms of sulfur. Some of the pyritic forms are pyrite (FeSi) itself, chalcocite (CuiS), and chalcopyrite (CuFeSi). The sulfur content of the raw mineral is usually 25-35%, but may run as high as 50%. To obtain the sulfur in a separated form, the original procedure was to pile the lumps of ore outside and seal these with clay or earth. Burning a part of the contained sulfur sealed into these mounds, with careful control of the air generated sufficient heat to melt any elemental sulfur present, and thermally decompose the pyrite (Eqs. 9.1-9.3) [10]. 

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