Showing papers on "Vapours published in 1984"
12 Nov 1984
TL;DR: In this article, an input grating couplers on planar SiO2-TiO2 waveguides are extremely sensitive sensors for humidity and other vapours (e.g., ethanol, acetone).
Abstract: Input grating couplers on planar SiO2-TiO2 waveguides are extremely sensitive sensors for humidity and other vapours (e.g., ethanol, acetone). Adsorption and desorption increase and decrease, respectively, the effective guide index and, thus, change the incoupling efficiency.
17 citations
Patent•
20 Jan 1984
TL;DR: In this article, the authors describe a circulatory process for concentrating and purifying sulphuric acid containing organic impurities, in which the acid to be prepared is continuously fed to an evaporation process with the input of heat and brought to a higher concentration with continuous separation of the vapours.
Abstract: 1. Circulatory process for concentrating and purifying sulphuric acid containing organic impurities, in which the sulphuric acid to be prepared is continuously fed to an evaporation process with the input of heat and brought to a higher concentration with continuous separation of the vapours, characterised in that the sulphuric acid to be prepared is fed to part of the acid leaving the evaporation process in concentrated form, at a distance from the point of separation of the vapours and gases from the liquid phase corresponding to the required heating path, forming a reaction line, and is led therewith to the said separation point, an oxidising agent being added in equidirectional flow to the acid to be prepared prior to its introduction into the liquid phase of the acid present in the vapourisation process.
11 citations
TL;DR: The major disadvantage in using this instrument was the missing selectivity towards individual compounds in a mixed atmosphere, but in all other respects the method is just as good as or better than the standard gaspipette method and the gasbag method.
Abstract: The use of a photoionisationdetector (PID) for measurement of alveolar concentrations of gases and vapours was evaluated during a human exposure experiment with toluene. Two other methods, the standard gaspipette method and the gasbag /charcoal method, was tested for comparison. The best method appeared to be the PID-method. The major disadvantage in using this instrument was the missing selectivity towards individual compounds in a mixed atmosphere. In all other respects, the method is just as good as or better than the standard gaspipette method and the gasbag method. Results from 40 measurements with the three methods on 16 persons were examined statistically, and the average toluene absorption at 100 ppm exposure levels was estimated to be 1.6 mg/min.
11 citations
TL;DR: The evaporation rate of pure pure mercury was measured after exposing a freshly formed mercury surface to nitrogen, oxygen, air and the vapours from pump oil and vacuum grease.
6 citations
TL;DR: In this article, the authors derived the fundamental equation for the pressure pal of the adsorbed phase by the thermodynamic treatment of micropore volume filling (MVF) process which also took into account the structural changes of the adorbate in the field of adsorption forces.
Abstract: The fundamental equation for the pressure pal of the adsorbed phase is derived by the thermodynamic treatment of micropore volume filling (MVF) process which also takes into account the structural changes of the adsorbate in the field of adsorption forces. The introduction of the principle of hydro-dynamical and mechanical equilibria reveals that MVF mechanisms can be characterized and classified according to the values of the pressures pfal corresponding to the beginning of MVF. The values of these pressures are calculated on the basis of experimental measurements of the length changes of the adsorbent rods during vapour adsorption. It is concluded, that the validity of the potential theory for MVF is based on the equality of the pfal and the standard liquid state pol pressures (mechanism MVF 1). The existence of negative pressures pal is typical for the MVF 2 mechanism. The positive values of pfal are characteristic for the intrusion of liquids into the micropores of solids, not wetted by the liquid (mechanism MVF 3).
4 citations
01 Jan 1984
TL;DR: A review of experimental and theoretical work on the ignition of gases and vapours by heating surfaces, including hot bodies, particles and rods is presented in this article, where it is shown that the case of ignition by hot surfaces bears little or no relation to their ignition temperatures.
Abstract: A review of experimental and theoretical work carried out (since 1816) on the ignition of gases and vapours by heating surfaces, including hot bodies, particles and rods is presented. It is shown that the case of ignition of gases and vapours by hot surfaces bears little or no relation to their ignition temperatures and that gases and vapours can be grouped according to their case of ignition by a given hot surface. Small particles must be at extremely high temperatures before they can cause ignition: the heat of combustion of particles that burn in air is an important factor. The implications of this work are discussed in relation to practical situations. 64 references.
3 citations
Patent•
04 Jul 1984
TL;DR: In this article, a process for energy recovery in beer wort boiling by condensation of the vapours on heat exchangers is described, which is characterised in that, in a start-up phase, the vapour are conducted away virtually unpressurised via a copper vapour condenser.
Abstract: The invention relates to a process for energy recovery in beer wort boiling by condensation of the vapours on heat exchangers, which is characterised in that, in a start-up phase, the vapours are conducted away virtually unpressurised via a copper vapour condenser (8), and the hop residue-containing condensate is discarded, whereupon in the main phase, part of the hop residue-free vapours is withdrawn virtually unpressurised with the exclusion of air using a steam jet pump (60) fed with superheated steam or saturated steam and condensed via further heat exchangers (70, 70', 70'', 74) and fed to the steam circulation together with the condensate, likewise no longer containing hop residues, by the copper vapour condenser (8).
2 citations
Patent•
29 Nov 1984
TL;DR: In this article, the authors proposed an energy-saving process for condensing spin bath vapours from the production of viscose, where the vapours are condensed by the sodium hydroxide solution required for the viscose production, but before this condensation, the vapour is scrubbed using a scrubbing liquid in a separate scrubbing circulation connected upstream, the temperature of which is adjusted to be high enough so that no steam condensation can occur during this scrubbing.
Abstract: In the energy-saving process for condensing spin bath vapours from the production of viscose, the vapours are condensed by the sodium hydroxide solution required for the viscose production, but before this condensation the vapours are scrubbed using a scrubbing liquid in a separate scrubbing circulation connected upstream, the temperature of which scrubbing liquid is adjusted to be high enough so that no steam condensation can occur during this scrubbing.
1 citations
Patent•
16 Jul 1984
1 citations
TL;DR: In this paper, conditions of forming extremal or anomalous temperature dependences of coefficients of mass-transfer are analyzed for gases and vapours, which have strong reversible interaction with active sorption centers in the polymer matrix.
Abstract: Experimental data are presented and conditions of forming extremal or anomalous temperature dependences of coefficients of mass-transfer are analyzed for gases and vapours, which have strong reversible interaction with active sorption centres in the polymer matrix.
TL;DR: In this paper, an efficient trapped mechanical rotary pump operating with completely degassed oil is shown to achieve a high vacuum rate of 12/s −1 and 400ls −1.