Gases atmospheric

Rotomolding. Nylon-6, nylon-11, and nylon-12 can be used in rotomolding and are generally suppHed for these appHcations as a powder or with a small pellet si2e. The process involves tumbling the resin in a heated mold to form large, thin-walled mol dings. Nylon-11 and nylon-12 use mold temperatures of 230—280°C and nylon-6 is processed at over 300°C. An inert gas atmosphere is preferred to avoid oxidation. [Pg.274]

Gas-flow counting is a method for detecting and quantitating radioisotopes on paper chromatography strips and thin-layer plates. Emissions are measured by interaction with an electrified wire in an inert gas atmosphere. AH isotopes are detectable however, tritium is detected at very low (- 1%) efficiency. [Pg.439]

TJItrahigh (99.999 + %) purity tellurium is prepared by zone refining in a hydrogen or inert-gas atmosphere. Single crystals of tellurium, tellurium alloys, and metal teUurides are grown by the Bridgman and Czochralski methods (see Semiconductors). [Pg.386]

Reduction. BrezeHus attempted the first reduction of zirconium in 1824 by the reaction of sodium with potassium fiuorozirconate. However, the first pure ductile metal was made in 1925 by the iodide thermal-dissociation method. The successfiil commercial production of pure ductile zirconium via the magnesium reduction of zirconium tetrachloride vapor in an inert gas atmosphere was the result of the intense research efforts of KroU and... [Pg.430]

Mixing cellulose esters in nonpolar hydrocarbons, such as toluene or xylene, may result in static electricity buildup that can cause a flash fire or explosion. When adding cellulose esters to any flammable Hquid, an inert gas atmosphere should be maintained within the vessel (132). This risk may be reduced by the use of conductive solvents in combination with the hydrocarbon or by use of an antistatic additive. Protective clothing and devices should be provided. [Pg.259]

In addition, these can be sealed for processes reqiiiring special gas atmospheres and exclusion of outside air. [Pg.1200]

Because indirect-heat calciners frequently require close-fitting gas seals, it is customaiy to support aU parts on a selFcontained frame, for sizes up to approximately 2 m in diameter. The furnace can employ elec tric heating elements or oil and/or gas burners as the heat source for the process. The hardware would be zoned down the length of the furnace to match the heat requirements of the process. Process control is normaUy by shell temperature, measured by thermocouples or radiation pyrometers. When a special gas atmosphere must be maintained inside the cyhnder, positive rotaiy gas se s, with one or more pressurized and purged annular chambers, are employed. The diaphragm-type seal ABB Raymond (Bartlett-Snow TM) is suitable for pressures up to 5 cm of water, with no detectable leakage. [Pg.1210]

Rotating electrical machines starting performance of single-speed three-phase cage induction motors for voltages up to and including 690 V Electrical apparatus for explosive gas atmosphere. Increased safety protection e 8789/1996 6381/1991 BS EN 60034-12/1996 BS 5501-6/1977... [Pg.48]

Electrical apparatus for explosive gas atmospheres Increased safely motors, type e . General requirements 6381/1991 BS. 5501-6/1977 BS 5000-15/1985 ... [Pg.192]

Electrical apparatus for explosive gas atmospheres. Increased safety motors. General requirements 6181/1991 BS 5501-6/1977 -... [Pg.270]

AMD 1 Electrical apparatus for explosive gas atmospheres. Classification of hazardous areas (AMD 9340) dated 15 November 1996. Superseded BS 5345 Part 2 1983... [Pg.591]

AMD 1 Electrical apparatus for explosive gas atmospheres. Electncal installations in hazardous areas (other than minesj. Comgendum No. 1 (Corr. 10013J dated April 1998, superseded BS 5345 Part 1 1989, Parts 2 and 7 1979, Part 4 1977, Part 5 1983, Part 6 1978 and Part 8 1980... [Pg.592]

Preparation of la-hydroxycholecalciferol a solution of 13.5 mg of 1a,3/3-dihydroxypro-vitamin D3 in 200 ml of ether is allowed to stand still in the dark at room temperature in an argon gas atmosphere for 2 weeks. During this period, the position of the maximum ultraviolet absorption is shifted from 260 m/u to 264 m/u, and the absorption intensity becomes... [Pg.36]

Polyethylene displays good heat resistance in the absence of oxygen in vacuum or in an inert gas atmosphere, up to the temperature of 290°C. Higher temperature brings about the molecular-chain scission followed by a drop in the molecular-weight average. At temperatures in excess of 360°C the formation of volatile decomposition products can be observed. The main components are as follows ethane, propane, -butane, n-pentane, propylene, butenes and pentenes [7]. [Pg.81]

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