Showing papers on "Vapours published in 2011"

On The Spectra Of Ignited Gases And Vapours: With Especial Regard To The Different Spectra Of The Same Elementary Gaseous Substance...

Abstract: 1. In order to obtain the spectra of all the elementary bodies, you may make use either of flame or the electric current. For this purpose flame is preferable on account of its easy management, and therefore was immediately introduced into the laboratory of the chemist. But its use is rather limited, the metals of alkalies being nearly the only substances which, if introduced into flame, give spectra exhibiting well-defined bright lines. In the case of the greater number of elementary substances the temperature of flame, even if alimented by oxygen instead of air, is too low. Either these substances are not reduced into vapour by means of flame, or, if reduced, the vapour does not reach the temperature necessary to render it luminous in such a degree that by prismatic analysis we obtain its characteristic rays. The electric current, the heating power of which may be indefinitely increased by increasing its intensity, is alone fitted to produce the peculiar spectra of all elementary bodies. 2. In applying the electric current we may proceed in two ways. In one mode of proceeding the substance to be examined by its spectrum is at the same time, by means of the current, transformed into vapour and rendered luminous. In the other mode the substance is either in the gaseous state, or, if not, has been converted into it by means of a lamp, and the electric current ignites the substance in passing through.

Effect of surfactant and oil additions in the biodegradation of hexane and toluene vapours in batch tests

Abstract: The biological treatment of gaseous emissions of hydrophobic volatile organic compounds (VOCs) results in low rates of elimination partially because of the low solubility of VOCs in water. Recently, the use of two‐phase partition bioreactors (TPPBs) was proposed to increase the bioavailability and consequently the elimination capacities of this kind of VOC. In the present study, TPPBs operating in a batch feed mode were tested for biodegradation of hexane and toluene vapours with a microbial consortium. The results obtained were compared with single‐phase systems (control experiments). The liquid phase used was silicone oil (organic phase) with the surfactant Pluronic F‐68. Experiments were named F1 and F2 for one and two phases, respectively, and F1S and F2S when the surfactant was included. The maximum specific rates (Srates) of hydrocarbon consumption for hexane and toluene were 539 and 773 mghydrocarbon/(gprotein·h), respectively. For both substrates, the systems that showed the highest Srates of hydr...

The trapping of indoor air contaminants

Abstract: The removal of indoor air contaminants by reactivity with air filters coated with reagents has been found to be effective for aldehydes, acidic and basic vapours as well as isocyanates Coatings of polymeric amines were used for formaldehyde trapping as well as for the removal of acidic vapours and for the removal of isocyanates. The addition of glycerol as a plasticizer for the coating can also be an effective reagent.

Method to process carbon-bearing gases and vapours

Abstract: FIELD: technological processes. ^ SUBSTANCE: invention relates to the method of processing gases and vapours that contain from 30 to 60 at. % of carbon, and also up to 70 at. % of oxygen and hydrogen, by exposure of a raw mixture that contains them to accelerated electrons to produce radiolysis products, in process of which a condensed fraction containing the target product is continuously removed from the radiolysis products, and the remaining part is mixed with source gas and/or vapour to produce the raw mixture, besides, hydrogen or hydrogen-bearing compounds of carbon are added to the mixture, or a condensed low-boiling fraction is added with boiling temperature below the boiling temperature of the target product, thus maintaining carbon percentage in the reaction mixture from 16 to 35 at. %, preventing oxygen content from going higher than 23 at. %. ^ EFFECT: method provides for the possibility to produce target fuel or raw materials for heavy organic synthesis from gaseous and steam-like raw materials, including carbon oxides, synthesis gases, cracking gases, steam-like products of biomass destruction, vapours of saturated and non-saturated organic compounds and production wastes; expands assortment and increases yield of synthesised commercially valuable condensed organic compounds; simplifies technology of their production due to replacement of high-temperature catalytic processing for direct electrophysical treatment, which does not require complicated preparation of raw materials; develops conditions for efficient management of the treatment process, composition and quality of the finished product. ^ 7 cl, 10 ex, 2 tbl

Thin films of mesoporous silicas as sensitive materials in gravimetric sensors for detecting or assaying vapours of nitrogen-containing compounds

Abstract: The invention relates to the use of a thin layer of mesoporous silica obtained by a sol-gel process as sensitive material in a gravimetric sensor for detecting vapours of one or more nitrogen-containing compounds. Applications: control/monitoring of atmospheric pollution and of air quality, monitoring of industrial sites.

Method for vacuum sublimation drying with convective input of thermal energy and vacuum sublimation drying installation

Abstract: FIELD: food industry. ^ SUBSTANCE: invention relates to food industry. In accordance with the method proposed evaporation of a liquid hydrophobic working medium is performed. The working medium vapours, moving as a result of differential pressure, are heated and passed through a layer of frozen product being dried. This process is performed one or several times, passing heated working medium vapours through, accordingly, one or several layers of frozen product being dried. The produced mixture of water vapours and working medium vapours is passed through one or more desublimators/absorbers where desublimation/absorption of water vapours from the mixture is performed. One performs condensation of working medium vapours and liquid working medium return to the process beginning. The working medium is represented by a low-boiling liquid or an easily liquefied gas. Proposed is a device for the method implementation. ^ EFFECT: usage of this group of inventions enables drying time reduction and prevention of contact of the product being dried with atmospheric oxygen. ^ 10 cl, 1 dwg

Controlled humidity drying

Abstract: The invention relates to a process for preparation of spray dried particles, comprising the steps of spraying in a chamber a liquid feed comprising one or more solvents, and supplying a drying gas to the chamber with one or more solvent vapours having a dew point selected to provide a desired property to the spray dried particles.

Carbon structures formation in low current high voltage electrical discharge in hydrocarbon vapours

Abstract: The properties of carbon fibers and other carbon structures produced from hydrocarbon vapours decomposed in electrically generated plasma at atmospheric pressure are studied in this paper. The electrical discharge was generated between a stainless steel needle and a plate made of nickel alloy. The carbon fiber has grown at the tip of the needle electrode, while other microflower-like deposits were built at the plate. The physical properties of carbon fibers were investigated by SEM, Raman spectroscopy, XRD, and EDS methods.

Procedure for application of molybdenum coating on metal powders

Abstract: FIELD: metallurgy ^ SUBSTANCE: invention refers to fabrication of metal coating, particularly, molybdenum on metal powders by thermal decomposition of hexa-carbonyl of molybdenum in medium of hydrogen sulphide and can be used for fabrication of anti-friction disperse-strengthened composite materials on base of polymer particles The procedure for application of molybdenum particles on metal powders consists in application of coating by thermal dissociation of vapours of molybdenum hexa-carbonyl Also, the main layer of applied coating consists of mixture of hexa-carbonyl of molybdenum and mono-oxide of carbon in volume ratio of vapours 1: 5 at 200C, whereupon produced layer is saturated with disulphide of molybdenum made of mixture of products of thermal dissociation of hexa-carbonyl of molybdenum and hydrogen sulphide in volume ratio of vapours 1: 2 at temperature 400C ^ EFFECT: fabrication of molybdenum coating on metal powders efficient in optimal operational combination of values of hardness, wear resistance and heat resistance of composite materials facilitating increased service life of parts of friction pairs made out of given composites ^ 2 tbl, 1 ex

Direct low temperature synthesis of carbon nanotubes on Si/SiO2 substrates without using a metal catalyst

Abstract: Metal-catalyst-free carbon nanotubes (CNTs) have been synthesised on Si/SO2 substrates via a novel two-zone Chemical Vapour Deposition (CVD) facility using ethanol vapours as carbon source. When the pyrolysis of the ethanol vapours is carried out at 1000 degreesC in the first zone of the CVD, in the second zone the formation of metalcatalyst- free CNTs is possible at temperatures as low as 500 degreesC. It was found that the chemical pre-treatment of the Si-substrate in liquid ethanol is critical for defects generation on a Si/SO2 surface which were found to be responsible for carbon precipitation and formation of the metal-catalyst-free CNTs. The role of the separation of the ethanol vapours pyrolysis from the CNT formation in the two-zone CVD and the role of ethanol pre-treatment of the Si/SO2 surface are discussed.

Process and plant for purifying monomers

Abstract: The present invention relates to a process for purifying moncomers, by evaporating at least a portion of the monomers present in a starting composition and then condensing it, which is characterized in that at least a portion of the starting composition is evaporated in a short-path evaporator, the mass flow density of the vapours m being selected according to the relation (I) m ≤ 1800 kg.√ k / mbar.m2.h.√ kg / kmol.Pi.(M / T)0.5 (I) in which M is the average molar mass of the vapours in the short-path evaporator in kg/kmol T is the temperature of the vapours in K Pi is the pressure in the short-path evaporator in mbar m is the mass flow density of the vapours in kg/(m2xh). A further aspect of the present invention is a plant for performing the process.