Showing papers on "Inert gas published in 1971"

Fuel tank inerting system

Abstract: A system for maintaining the oxygen content in the fuel vapor space of an aircraft fuel tank at less than 10 percent by volume, such system including an aspirating type mixing nozzle that draws an inert gaseous mixture from the tank vapor space and mixes it with liquid fuel being supplied to the tank whereby said inert gaseous mixture scrubs dissolved oxygen from the fuel and returns to the vapor space with the scrubbed oxygen therein. The tank includes a vent means for venting excess gasses from the vapor space to the tank exterior as the tank fills with fuel and also includes means for further scrubbing of oxygen from the fuel during climb of the aircraft and for pressurizing the tank with inert gas during descent while excluding air from the tank.

Apparatus for refining molten aluminum

Abstract: The apparatus of the invention is capable of injecting gas in the form of small discrete bubbles into a mass of molten metal. The apparatus comprises a rotatable shaft coupled to drive means at its upper end and a vaned rotor at its lower end. Gas under sufficient pressure to be injected into the melt is fed into a passageway extending axially through the device whereby upon rotation of the rotor the gas is injected into the molten metal and subdivided into discrete gas bubbles. The process of the invention utilizes the above described gas injection apparatus for refining molten aluminum by introducing an inert gas into the metal beneath the surface of the melt.

Treatment of molten metal by injection of gas

Abstract: Molten metal is treated by flowing gas through it. The container for the treatment is provided with a fore hearth, with a cover and with means for blowing the gas in fine bubbles into the metal. From the container the treated metal flows into a hopper provided with a cover having means for flushing the hopper with an inert gas.

Preparation of ceramics

Abstract: A method for preparing ceramic material from a polymer which comprises selecting a polymer from the class consisting of poly(diorganosilanes), poly(haloorganosilanes), poly(carbosilanes), polysilazanes, polycarbocarboranes, and polyborazines; heating said polymer to a temperature from 700° to 2000° C at a rate of at most 100° C/hr. in an inert atmosphere for at least one hour; and cooling to room temperature at a cooling rate which avoids thermal stresses.

Apparatus for automatically performing chemical processes

Abstract: AN AUTOMATIC PROTEIN-PEPTIDE SEQUENATOR FOR DETERMINING THE AMINO ACID SEQUENCE IN PROTEINS AND/OR PEPTIDES CONTAINING N NUMBER OF AMINO ACID UNITS INCLUDING: AN EASILY ACCESSIBLE REACTION CELL DISPOSED WITHIN A REACTION CHAMBER HAVING A MINIMUM VOLUME AND ROTATIONALLY DRIVEN BY A VARIABLE OR MULTIPLE SPEED MOTOR THROUGH A MAGNETIC COUPLING DRIVE UNIT, AIR-CIRCULATING HEATING MEANS, A CONSTANT PRESSURE AND UNIFORM DELIVERY SYSTEM INCLUDING VACUUM AND SOLENOID ACTUATED VALVE ASSEMBLIES, A REGULATED INERT GAS SUPPLY SYSTEM, AN EVACUATED FRACTION COLLECTOR, AND A PROGRAMMING CONTROL UNIT WHICH MAY BE AUTOMATICALLY OR MANUALLY MANIPULATED.

Method of preparing inorganic aerogels

Abstract: SILICA AEROGELS ARE PREAPRED BY HYDROLYZING A LOWER ALKYL ORTHOSILICATE IN AN ALIPHATIC ALCOHOL HAVING 1-4 CARBON ATOMS WITH ONE TO FIVE TIMES THE STOICHIOMETRIC QUANTITY OF WATER REQUIRED TO EFFECT HYDROLYZATION. IN A SEPARATE VESSEL, A SUPPLEMENTARY AMOUNT OF THE SAME ALCOHOL IS ADDED AND THE CONTENTS OF BOTH VESSELS ARE GRADUALLY HEATED TO A TEMPERATURE ABOVE THE CRITICAL POINT. THE PRESSURE IS GRADUALLY RELEASED AND WATER AND ALCOHOL VAPORS ARE WASHED OUT WITH DRY INERT GAS. THE AUTOCLAVE IS THEN RESEALED AND COOLED TO ROOM TEMPERATURE AND THE RESULTING AEROGEL IS COLLECTED.

Method of producing flat (non-glossy) films

Abstract: A flat film or coating is prepared by subjecting a substantially solventless, actinic light, or radiation-sensitive material to ionizing irradiation or actinic light in an oxygen-containing atmosphere and subsequently subjecting the material to ionizing irradiation or actinic light in an inert gas or an atmosphere containing less than about 1000 parts per million of oxygen. The preferred films or coatings are prepared from polyacrylates or unsaturated polyester resins.

Inert gas system for a tanker

Abstract: AN INERT GAS FOR FLOODING COMPARTMENTS OR OTHER OIL CONTAINERS OF A TANKER OR OTHER VESSEL IS PRODUCED BY STRIPPING FLUE GAS OF ITS SO2 CONTENT WITH AN AQUEOUS SODIUM HYDROXIDE OR SODIUM CARBONATE SOLUTION IN A SCRUBBER, AND OXIDIZING THE RESULTING SODIUM SULFITE IN THE SOLUTION WITH ATMOSPHERIC OXYGEN IN THE SAME SCRUBBER, WHEREUPON A SODIUM SULFATE SOLUTION IS OBTAINED WHICH MAY BE DISCHARGED OVERBOARD WITHOUT DAMAGE TO MARINE LIFE.

Photolysis of Formaldehyde at 1470 and 1236 Å

Abstract: Formaldehyde vapor photodecomposition modes by end product analysis, utilizing mixed isotope, radical scavenger, inert gas pressurization and lamp intensity attenuation

Food packaging system and method

Abstract: Disclosed are a method of and system for packaging commercially sterile foods by placing the sterile food in a plastic container tending towards opacity to visible light radiation and tending towards transparency to ultraviolet radiation. The container is open and the food product is cooled to a temperature slightly above the freezing point of water preparatory to and while in a chamber having an atmosphere of cooled, dry inert, sterile gas. In the chamber, the inert gas and food product are irradiated by ultraviolet energy that propagates through the container. The container is sealed in the chamber, whereby the inert atmosphere is maintained on the surface of the food product while stored in the container, at temperatures slightly above the freezing point of water for prolonged time periods.

Process for the recovery of mercury from mercury containing liquids

Abstract: A PROCESS IS PROVIDED FOR RECOVERING MERCURY FROM MERCURY-CONTAINING LIQUIDS BY STRIPPING THE MERCURY AS VAPOR FROM THE LIQUID WITH AN INERT GAS, AND WASHING THE MERCURY VAPOR-CONTAINING INERT GAS WITH A SOLUTION CONTAINING AN OXIDIZING AGENT, SUCH AS ACTIVE CHLORINE, SO AS TO ABSORB THE MERCURY VAPOR AND OXIDIZE ELEMENTAL MER- CURY TO MERCURY ION WHICH CAN THEN BE DISSOLVED IN THE SOLUTION IN THE FORM OF COMPLEX MERCURY IONS SUCH AS MERCURY CHLORIDE COMPLEX IONS.

A Born model calculation of the energies of vacancies, ion interstitials and inert gas atoms in calcium fluoride

Abstract: The energy of inert gas interstitials and the activation energy for gas diffusion have also been calculated Values for the binding energy of the gas into vacancies suggest that there may be a slight modification of the diffusion due to gas trapping All the calculations were performed by minimizing the energy with respect to the displacements and dipoles of ions in a relatively large region (15-20 shells) surrounding the defect A new numerical method used in the calculation of the relaxation is ten or twenty times faster than conventional minimization methods

Process of producing enzyme compositions

Abstract: PRILLS COMPRISING AN ENZYME AND A NORMALLY SOLID WATER-SOLUBLE TRANSLUCENT MATERIAL ARE MADE BY A PROCESS WHEREIN THE RESULTANT PRILLS HAVE A RELATIVELY LIGHT COLOR. A SLURRY OF THE ENZYME AND NORMALY SOLID WATER-SOLUBLE TRANSLUCENT MATERIAL IS INJECTED WITH AN INERT GAS AND THEN MADE INTO PRILLS BY AN PRILLING METHOD. AN ESPECIALLY PREFERRED METHOD OF MAKING THE PRILLS IS BY SPRAY COOLING. THE INERT GAS INJECTION STEP PRIOR TO PRILLING RESULTS IN PRILLS HAVING A HUNTER COLOR L-VALUE OF ABOUT L-70 TO L-90, SIGNIFICANTLY HIGHER THAN THE L-VALUE OF PRILLS MADE BY A PRILLING TECHNIQUE NOT EMPLOYING THE INERT GAS INJECTION STEP. EACH OF THE RESULTANT PRILLS IS IN THE FORM OF A SUBSTANTIALLY SPHERICAL SHAPE HAVING A SUBSTANTIALLY SMOOTH OUTER SURFACE AND POROUS INTERIOR.

Trapping and diffusion of rare gases in phillipsite, zeolite K—M and other silicates

Abstract: The potential of a number of silicates, of the felspathoid, fibrous clay, zeolite and other silicate groups, has been investigated for the trapping and storage of inert gases. The crystals, suitably outgassed, were exposed to high pressures of inert gas at high temperature and then quenched while still under pressure. In phillipsite and zeolite M, isotherms and diffusion coefficients were measured. Energy barriers for diffusion in a range of crystalline aluminosilicates are related to the free dimensions of the openings giving access to the intracrystalline cavities, with complications associated inter alia with cation siting and entrained impurity.

Oxidation of alkyl aromatics

Abstract: Process of liquid phase oxidation of the alpha carbon atom of alkylbenzenes by a manganic or cobaltic salt and an acid activator with or without an oxidation-resistant solvent either in an inert atmosphere to produce lower oxidation products of the alpha carbon atom such as alcohols or their esters; or, in the presence of molecular oxygen, to produce higher oxidation products such as aromatic aldehydes, ketones or carboxyl acids.

Process for preparing a layer of compounds of groups ii and vi

Abstract: A process for preparing a layer of compounds of Groups II and VI characterized in that a layer of the compounds is formed on the surface of a substrate, and the formed layer is heat-treated in an atmosphere comprising an inert gas, 0.1-10% by volume of oxygen on the basis of said inert gas and vapour of at least one element selected from a group consisting of sulfur, selenium and tellurium so that uniform grain growth with a narrow range grain size distribution is effected.

Processing of fruit without exposure to air

Abstract: A method wherein harvested grapes are put into an inert gas atmosphere immediately after being harvested in the field and the grapes are kept in an inert atmosphere, out of contact with oxidizing air, as they are taken from the field to the winery and at all times during the various process steps at the winery. Inert gas under pressure is used to move the harvested grapes and the succeeding processed wine juice from one station to another to prevent contamination by pumps. Carbon dioxide generated during the fermentation step is used as the source of inert gas.

Method for improving fuel combustion in a furnace and for reducing pollutant emissions therefrom

Abstract: A method for improving fuel combustion in furnaces and the like and for reducing pollutant emissions therefrom, wherein primary air is used solely for fuel feed while commercially pure oxygen without any additives or other constituents is introduced for the combustion of the fuel in regulated amounts so as to provide sufficient oxygen for substantially complete combustion. The oxygen is preferably obtained by separating same from air so that the remaining nitrogen may be used as in inert gas applications.

Calibration of inert gas exchange in the mouse

Abstract: Publisher Summary This chapter highlights the usefulness of the common laboratory mouse as an experimental animal in decompression studies. Although the mouse is vastly different from man on an absolute basis quantitatively, the relative effects of gas mixtures, decompression profiles, and drugs in the mouse might be quite similar to those in man. Initial studies were directed toward an analysis of inert gas exchange in the mouse. As the inert gas tension following saturation is uniform throughout the tissues regardless of the time courses of their approach to saturation, the curves presented in the chapter provide a reference against which to compare the non-saturation exposures in which the inert gas uptake by a tissue is a function of both the exposure time and the tissue-inert gas exchange time constant.

A redetermination of the thermal diffusion factor for some inert gas mixtures. I

Abstract: As a result of improvements in the method of analysis of gas mixtures, which permit detection of changes in mole fraction of 1 part in 105, a redetermination of the thermal diffusion factor for some gas mixtures of special interest in progress. Results are given here for argon-neon and krypton-argon mixtures. The intermolecular potential functions commonly used in connection with other transport properties of gases fail to account for the observed variation of the thermal diffusion factor at temperatures approaching the condensation point of one of the components, and this is attributed to dimerization.

Apparatus for crushing fruit in an inert gas

Abstract: An enclosed fruit-crusher, discharging into an enclosed tank filled with an inert gas, which, as it is filled with crushed fruit, displaces the inert gas from the tank through the crusher and out the crusher inlet, thereby preventing entry of oxidizing air into the crusher or tank at all times during filling and crushing Inert gas under pressure is introduced into the tank as crushed fruit is discharged therefrom, thereby refilling the tank with inert gas and preventing contact of the crushed fruit with oxidizing air during emptying

A Born model calculation of the energies of vacancies, ion interstitials and inert gas atoms in strontium and barium fluorides

Abstract: The author has extended previous calculations of the energies of vacancies, ion interstitials and inert gas atoms in calcium fluoride and obtained new results for the systems Kr/SrF2 and Xe/BaF2.

Process and apparatus for purging gas-containing storage tanks in vessels

Abstract: A process and apparatus for purging gas storage tanks comprises generating a gas inert with respect to the stored gas, displacing the stored gas in the tank with part of the inert gas and admixing another part of the inert gas with the stored gas displaced from the tanks, whereby in the case of combustible stored gas explosive mixtures are avoided. The inert gas may be generated by burning a portion of the stored gas or another fuel.

Apparatus and process thereof for coating with polytetrafluoroethylene and other materials

Abstract: An apparatus and method thereof are described for coating surfaces with a continuous unitary film of polytetrafluoroethylene (PTFE) by spraying a heated stream of particles from a spray gun. The gun includes a heating means such as an electrical resistance unit, a mixing chamber where gas and preferably inert gas is mixed with the particles, and means for directing a stream of gas through the gun to force the heated particles onto the surface to be coated. Obviously, other plastic materials may be used at their appropriate melting temperatures.

Growth of crystals from the gas phase. Part II. Diffusional limitations and interfacial stability in crystal growth by dissociative sublimation, with an inert third gas present

Abstract: The quantitative treatment of interfacial stability in crystal growth from the vapour phase, presented in a previous paper, has been extended to cover (1) large temperature differences between source and seed, (2) arbitrary temperature profiles, and (3) an inert third species in the gas phase. The effect on the growth rate and critical growth rate of altering the temperature profile has been investigated and found to be small if the slope at the growing interface is above about 10 K cm–1. The influence of small quantities of inert gas on the temperature difference corresponding to the critical growth rate is shown to provide a useful stabilising effect against unavoidable temperature fluctuations. At the same time, the partial pressure ratio α of the active components becomes a less sensitive function of the distance along the growth capsule. The treatment is general; however, the familiar case of cadmium sulphide is included as an illustration and for comparison with our previous results.

Deposition of alloy films

Abstract: A glow discharge is established by applying a high voltage between an anode and a cathode object disposed in an inert gas atmosphere. An alloy of two or more metals is vaporized and the vapor injected into the glow discharge causing the alloy to be plated onto the cathode object.

Equilibrium Computation for the Growth of Alpha Silicon Carbide from Silane and Propane in the Presence of Hydrogen or an Inert Gas

Abstract: The equilibrium computation for the growth of α-SiC from silane and propane in an atmosphere of hydrogen or an inert gas is carried out. The dependence of the deposition ratios of α-SiC, Si(l) and C(graphite) and the partial pressures of the vapor species on the concentration of the reactants and on the temperature is analyzed in detail. It is shown that in hydrogen atmosphere the deposition of α-SiC single phase occurs over a wide range of reactant partial pressures, i.e., from P(SiH4)=3×P(C3H8) to a significant propane excess. In the presence of an inert gas this range is limited to the vicinity of P(SiH4)=3×P(C3H8). This difference is apparently attributed to that the inert gas cannot remove the excess carbon into the vapor phase. Additional thermodynamic characteristics of these systems are also discussed.

Interpretation of Alkali–Inert Gas Beam Scattering with the Buckingham–Corner Potential

Abstract: We have shown that recent measurements of alkali–inert gas beam scattering cross sections can be fit by a four parameter Buckingham–Corner potential with the same accuracy as with previously proposed four to seven parameter models. The Buckingham–Corner model contains a single Born–Mayer repulsive term and two attractive terms, the ordinary Van der Waals attraction and the second term in the London dispersion series. This model gives the correct broadening of the potential well. In addition some of the terms can be calculated theoretically. A fit of the measured total and differential cross sections for the systems Na–Xe and Na–Kr yields a set of form parameters which we assume to be characteristic of the alkali–inert gas interaction. Using these one can deduce well parameter values for each particular combination. Since the fit of the Buckingham–Corner potential is determined from the oscillatory structure of thermal beam measurements, its validity is confirmed only in the attractive region. A possible application of the model to the inert gas–inert gas interaction is discussed.

A Mathematical Approach for the Mass Transfer Between Liquid Steel and an Ascending Bubble

Abstract: A mathematical model which is adaptable to practical conditions has been put forward to deseribe adequately the purging of liquid steel with an inert gas. The mass transfer between liquid steel with varying C, O, H, N, and S contents and an ascending argon bubble has been investigated. The simultaneous mass transfer of all possible gaseous compounds is considered as a function of the initial bubble mass, height of the steel bath, the bulk concentrations in the melt, and the external pressure. The model takes into account the change in size and form of the bubble resulting from its rise and the mass transfer between the bubble and the melt, and also the influence of surface active agents such as sulfur and oxygen. The following general conclusions can be drawn: 1) the gases flushed (out of the melt) by the bubble can be related to the amount of argon injected into the bath. 2) Increase in the initial bubble size and the content of the gas in the bath to be purged, and decrease in the external pressure result in more pronounced deviations from equilibrium saturation within the bubble. 3) Lower external pressure, increasing supersaturation of CO, and greater amounts of purging gas at higher dispersion are the chief factors responsible for increasing, purging efficiency for H, N2, CO in steel melts. 4) Surface-active agents decrease the purging ratio for nitrogen in a carbon-free melt, but, in carbon-containing melts, increasing amounts of oxygen alone lead to a considerable increase in the purging ratios for nitrogen due to the high mass transfer of CO to the bubble. In the latter case, the effect of increasing sulfur content on the purging ratios is of no significance.