Fume, fumes

LIQUIDS LIQUIDS LIQUIDS LIQUIDS LIQUIDS FUMES FUMES FUMES FUMES -EFFLUENT... 

Fumes - Fumes are finely divided solid partieles that are generated by the condensation of vapors. Fumes are generally the by products of sublimation, distillation, and molten metal processes. Particle diameters are generally in the range of 0.1 to 1 /im. 

Note Note that the diazotization of primary aromatic amines can also be achieved by placing the chromatogram for 3 — 5 min in a twin-trough chamber containing nitrous fumes (fume cupboard ). The fumes are produced in the empty trough of the chamber by addition of 25% hydrochloric acid to a 20% sodium nitrite solution [2, 4], iV-(l-Naphthyl)ethylenediamine can be replaced in the reagent by a- or -naphthol [10, 14], but this reduces the sensitivity of detection [2]. Spray solutions Ila and lib can also be used as dipping solutions. 

Silicon tetrachloride can be used to produce a smoke like powder known commercially as silica fume (fumed silica, pyrogenic silica) by reaction in an oxygen-hydrogen flame ... 

Fumes Fumes are formed by processing, such as combustion, sublimation, or condensation. The term is generally applied to the metal oxides of such metals as zinc, magnesium, or lead. 

Fumes Fumes are fine solids less than 1 pm in size often formed by condensation of vapors. For example, heating of lead vaporizes some lead material that quickly condenses to small, solid particles. 

Fumes are created when a solid substance melts. As it is heated, some of the solid vaporizes and enters the surrounding air. As this vapor cools, it produces solid particles that remain suspended in the air as fumes. Fume particles are usually very small, less than one micron in diameter, and can be inhaled. Welding is an example of a process that generates fumes. 

AcjO acetic anhydride fum fumes, fuming Pr propyl... 

Ac acetyl fir fum fluorescent fumes, fuming Pr PrOH propyl 1-propanol... 

The first major hazard in process plants is fire, which is usually regarded as having a disaster potential lower than both explosion or toxic release. However, fire is still a major hazard and can, under the worst conditions, approach explosion in its disaster potential. It may, for example, give rise to toxic fumes. Let us start by examining the important factors in assessing fire as a hazard. 

H2N (CH2]5 NH2. a syrupy fuming liquid, b.p. 178-180 - C. Soluble in water and alcohol. Cadaverine is one of the ptomaines and is found, associated with pulrescine, in putrefying tissues, being formed by bacterial action from the amino-acid lysine. It is found in the urine in some cases of the congenital disease cystinuria. The free base is poisonous, but its salts are not. 

Ditrosonium hydrogen sulphate, chamber crystals, NOHSO4. White solid m.p. 73°C (decomp.). Prepared SO2 and fuming nitric acid. Used in diazotization. 

Nordhausen sulphuric acid See sulphuric acid, fuming. 

C4H N. Almost colourless, ammonia-like liquid, b.p. 88-89 C, which fumes in air. Strong base. It occurs naturally in tobacco leaves, but is made industrially by hydrogenation of pyrrole. 

Tin IV) chloride, SnCU, stannic chloride. M.p. — 33" C, b.p. 1I4°C. Colourless fuming liquid (Sn plus CI2) hydrolysed in water but forms SnCl4,5H20 and [SnCl p" from acid solutions, soluble in organic solvents. Used as a mordant. 

CF3CO2H. Colourless liquid, b.p. 72-5 C, fumes in air. Trifluoroacetic acid is the most important halogen-substituted acetic acid. It is a very strong acid (pK = o y) and used extensively for acid catalysed reactions, especially ester cleavage in peptide synthesis. 

The above methods for obtaining D, as well as other ones, are reviewed in Refs. 3-12, and Refs. 7-9 give tables of D values for various adsorbents. For example, D is close to 3 for the highly porous silica gels and close to 2 for nonporous fumed silica and for graphitized carbon black coconut charcoal and alumina were found to have D values of 2.67 and 2.79, respectively [7]. 

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