Showing papers on "Vapours published in 1973"

Synthesis of bis-π-benzene-titanium and -molybdenum using metal vapours

Abstract: Bis-π-benzene-titanium and -molybdenum are formed by co-condensation of benzene vapour with the metal vapours at 77K.

Method for the qualitative and quantitative detection of vapours from low volatility compounds

Abstract: A method and apparatus for detecting and identifying low concentrations of vapours in the atmosphere and emanating from materials having low vapour pressures. The vapours are isolated from the atmosphere by being drawn through a membrane having a greater permeability to the vapours than the remainder of the atmosphere. The presence of the vapours is detected by an electron capture detector and thereafter the vapours are separated one from another for individual identification in the detector.

Detection and analysis of gases or vapours

Abstract: Method and apparatus for detecting and analysing gases and vapours uses a semiconductor material maintained at a temperature in the vicinity of its so called ''''exhaustion region.'''' In the presence of the gas condition to be detected or analysed, the electrical conductivity of the semiconductor material is changed, and this changes the maintained temperature of the semiconductor material so that its sensitivity to gas is increased.

Solvent sepn. from air using activated carbon - with programmed cycle of adsorption and regeneration to obt. high purificn.

Abstract: In a method for removing solvent vapours from air, by activated carbon adsorption and regeneration of the carbon by steam desorption, >=2 activated carbon chambers are used, the sequence of adsorption and regeneration being automatically regulated as a function of the concn. of solvent vapours, pref. by switching from adsorption to regeneration when the concn. of the vapours in the air on the discharge side of the adsorber exceeds a predetermined value. Pref., regeneration is commenced with a very high steam flow, using superheated steam, followed by more moderate flow, then drying. The redn. from high to moderate flow can be continuous or by steps, as the solvent concn. decreases. The number of activated carbon chambers in operation is given by n = (tA - tR)/tA (where tA is adsorption period; tR is regeneration period; and n is > rounded off to the next highest whole number).

Mass spectrometric studies on the vaporization of lithium perrhenate

Abstract: The equilibrium vaporization of LiReO4 over the temperature range 750–950 K has been studied. LiReO4 was evaporated from single and double Knudsen cells and the effusing vapours were examined by means of a MI-1305 mass spectrometer specially adapted for high temperature studies. Molecules of LiReO4 and of (LiReO4)2 were found in the vapours. The partial pressures and heats of vaporisation of monomer and dimer, and the heat of thermal dissociation of the dimer, were determined.

Treatment of condensates

Abstract: Aqueous liquids resulting from the condensation of vapours emitted by aqueous vegetable extracts are purified by treatment with an ion exchange resin The purified condensates may be used for the extraction of the vegetable material

Average Energy per Ion Pair for Alpha Particles in Vapours of Several Dielectric Liquids

Abstract: The W -values for alpha particles in several kinds of vapours have been determined. A cylindrical ionization chamber of inside diameter 20 cm and length 55 cm was used for measurements. Alpha particles emitted from 210 Po source entered to the ionization chamber through a collimator with mylar window. The vapours, were obtained from highly purified samples for spectroscopy. For the vapours, relative measurements with argon, nitrogen, and dried air as standard gases have been carried out. The W -values obtained within about 3 percent error for the vapours of n -hexane, cyclohexane, benzene, carbon disulphide, dichloromethane, and carbon tetrachloride were 29.1±0.5, 28.1±0.6, 30.9±0.7, 26.0±0.5, 26.8±0.5, and 28.7±0.7 eV, respectively. These W -values were somewhat large in comparison with those for electrons.

Gas/vapour treatment of conditioning agents - prior to electrostatic separation of minerals

Abstract: Conditioning agents (e.g. o-cresotic acid, salicylic acid) used for the preliminary chemical treatment of mineral mixtures, esp. of crude K-salts, before electrostatic separation, are subjected to acidic or basic gases or vapours before use. The separation thereby requires less conditioning agent. The treatment can be carried out with a single gas/vapour, mixtures or several cpds. applied successively. The gas/vapour state (if not existing under normal conditions) is attained by reduced pressure or elevated temp. The conditioning agent can be in pure form as a mixture, in soln. or on a carrier.

Purifying lactams - by treating vapours with active carbon

Abstract: Method for purifying lactams by passing their vapours at temps higher than their condensation point over or through activated carbon Residence time is pref 1-5 (esp 2-3) sec For epsilon-caprolactam, temp used is 180-300 degrees C Inert gas is opt present The carbon can be regenerated by solvent-extraction or superheated steam

The conductivity of alkali metal vapours

Abstract: A comparison is made of the calculated conductivities, including the effects of atomic clusters, of saturated sodium, potassium and caesium vapours. It is shown that the dependence of the conductivity on pressure at a fixed temperature has a form which could enable the presence of clusters to be deduced without requiring an accurate knowledge of the electron scattering cross section.