Vapours

About: Vapours is a research topic. Over the lifetime, 1153 publications have been published within this topic receiving 15022 citations.

Binary adsorption of vapours in active carbons described by the combined theories of Myers-Prausnitz and Dubinin. (II)

Abstract: The new MPD method, described recently, has been applied to the adsorption of benzene +1,2-dichloroethane vapours by a typical active carbon at 293 K. A total of 102 experiments have been carried out for adsorbed mole fractions between 0.06 and 0.94. Good agreement was found between the experimental and calculated values of the selectivity of the carbon for benzene, which decreased as the mole fraction of benzene increased. This variation reflects the heterogeneity of the carbon, which is taken into account by the DR equation. Although the liquid mixture is ideal, deviations from Raoult's law are observed in the adsorbed state, indicating a clear preference for benzene. The values of the activity coefficients obtained from the liquid/solid equilibrium improve the fit of the MPD method.

Process for recovering aroma from tea

Abstract: Disclosed is a process for recovering volatile aroma compounds from a tea material. The process comprises the steps of: generating aroma-laden vapours at a pressure of from 0.5 to 1.4 bar absolute from the tea material contacted with water or water vapours,and then condensing the aroma-laden vapours to recover aroma condensate. The process is controlled such that the mass of aroma condensate generated per unit dry mass of tea material is greater than 2 and the aroma-laden vapours comprise no more than 1% by weightentrained liquid.

SOSAA – A new model to simulate the concentrations of organic vapours, sulphuric acid and aerosols inside the ABL – Part 2

Abstract: Natural and anthropogenic aerosols may have a great impact on climate as they directly interact with solar radiation and indirectly affect the Earth’s radiation balance and precipitation by modifying clouds. In order to quantify the direct and indirect effects, it is essential to understand the complex processes that connect aerosol particles to cloud droplets. Modern measurement techniques are able to detect particle sizes down to 1 nm in diameter, from ground to the stratosphere. However, the data are not sufficient in order to fully understand the processes. Here we demonstrate how the newly developed one-dimensional column model SOSAA was used to investigate the complex processes of aerosols at a boreal forest site for a six-month period during the spring and summer of 2010. Two nucleation mechanisms (kinetic and organic) were tested in this study, and both mechanisms produced a good prediction of the particle number concentrations in spring. However, overestimation of the particle number concentration in summer by the organic mechanism suggests that the OH oxidation products from monoterpenes may not be the essential compounds in atmospheric nucleation. In general, SOSAA was correct in predicting new particle formation events for 35% of the time and partly correct for 45% of the time.

The effect of various vapours on the strength of compacted silica

Abstract: A method of compacting silica gel powder is described together with details of the surface changes that accompany such a process. The strength of discs of this material in vacuum and in the presence of different pressures of various gases and vapours are given. Carbon tetrachloride at room temperature has no effect. Nitrogen at liquid nitrogen temperature (−195.8°) causes a small decrease in strength. Water-vapour at room temperature even in small quantities causes a sharp fall in strength.