Abstract: New polythiols-polyesters and corresponding polysulphides in the --SH group wherein sulphur is contained in the alcohol residue after the formation of esters. These polyesters are derived from aliphatic polyacids, saturated or not, wherein the molecule contains a minimum of 15 atoms of carbon. They are formulated by the action of a mercapto-alcanol on the corresponding polyacid, in a liquid which gives an azeotropic mixture with water. These products are useful as additives to asphalts, bituminous products, coatings, mastics and cements.

Abstract: An improved method of producing dialkyl-sulfoxides by oxidizing corresponding dialkyl-sulfides with hydrogen peroxide in aqueous acidic medium. It remedies the drawback of the similar prior art as concerns the separation of the sulfoxide formed from its reaction medium. The new method permits of easily recovering the sulfoxides in the state of good purity.The improvement consists in mixing the reaction medium with a large proportion of a solvent capable of yielding an azeotropic mixture with water. Then, after oxidization, the water is removed by distillation as azeotropic mixture. Preferably solvents are used which dissolve the dialkyl-sulfide but do not dissolve the sulfoxide formed; heptane is a particularly useful solvent. When an excess of the solvent is used, there is obtained, after distilling off the azeotropic mixture, a slurry of sulfoxide and solvent, easy to separate.

Abstract: In a current-density controlled source of high-voltage current fed from a low-voltage current source and supplying a high-voltage direct current to two output terminals, an error voltage resulting from the comparison of a constant reference voltage and the voltage appearing at the terminals of a resistor through which flows a current proportional to the current to be controlled acts on the amplitude of an alternative current signal produced by an oscillator, the amplitude variations of the signal produced by said oscillator causing the amplitude high voltage current supplied to said output terminals to vary.

Abstract: The present invention is related to a device for measuring the mass of particles of an aerosol per volume unit. It comprises a solid measuring body, measuring means for measuring the resonance frequency of said solid measuring body, means for generating a flow of air loaded with particles and for directing said air flow toward a planar receiving electrode and means for electrically loading said particles with a polarity opposed to that of the planar receiving electrode.

Abstract: Novel polymeric diphosphine coordinates are obtained by reacting a diphosphine alkali alcoholate with an halogenated polymer, and their metal derivatives are obtained by reacting the coordinate with salts or transition metal complexes.These metal polymers can be used as catalysts in catalysis reactions by means of coordination complexes.

Abstract: A carburettor for an internal combustion engine including a main duct and an auxiliary duct which receive air from a valved inlet, a main valve in each of the ducts for controlling flow through the ducts. Fuel is introduced into the auxiliary duct upstream of the main valve therein but downstream of an auxiliary valve in the auxiliary duct which is used to control the fuel to air ratio of the fuel/air mixture produced by the carburettor. The auxiliary valve is controlled in accordance with engine temperature, pressure drop across air filter, degree of dilution of recycled exhaust gases, degree of combustion of exhaust gases, temperature of air entering the engine, or atmospheric pressure.

Abstract: A device for generating sound waves for use in shallow terristrial seismology incorporates a percussion mass, a motor for driving the percussion mass to strike the ground for intermittent contact and adjustable to vary the frequency of impact, and a sensing element to provide a signal indicative of at least the instant of impact and preferably also the deceleration amplitude of impact.

Abstract: This invention concerns a method of analysis by liquid-phase chromatography with programmed elution gradient.According to this method, two chromatography columns, of at least approximately similar porous volume and permeability, are each fed with a mixture of two solvents, in such a way that at any point in time the concentration of one of the solvents at the inlet to the first column is the same as the concentration of the other solvent at the inlet to the second column; the substance for analysis is injected into the inlet of one of the two columns; and the fluids leaving both columns are added to each other to form a mixture for analysis in a concentration detector.The main purpose of the method is to ensure better analysis of petroleum cuts.

Abstract: The adjustable aperture of a petrol metering element of a carburetor for internal combustion engines discharges directly into the body of the carburetor and is centered substantially on the geometrical axis of the stream of air in the said body, the petrol clearance height not being greater than about 10 mm.

Abstract: A hydraulic safety stop-valve fitted with hermetic sealing means.The equalization passage between pressures above and below the stop-valve comprises two means of sealing, one provided by contact between two truncated conical bearing surfaces on the outer casing and inner tube, and the other consisting of valves, held by springs against the equalization passage inlet apertures, bored in the lower tubular element of the outer casing, and the opening of which is controlled by a truncated conical surface on the inner tube.This device ensures a high level of safety in stop-valves used in large production tubings for wells at sea.

Abstract: A carburettor for an internal combustion engine includes a chamber into which fuel is introduced from a metering valve to produce a fuel/air mixture in the chamber. A main valve controls the rate of flow of fuel/air mixture from the chamber and a further valve upstream of the main valve is provided the opening of which controls the opening of the metering valve. The further valve opens so as to keep the pressure between the main and further valve constant with changes in flow rate through the chamber. Means are provided to provide an indication of the pressure of fuel/air mixture downstream of the main valve such that the metering valve can be further opened as a function of changes in said pressure downstream of the main valve.

Abstract: The present invention concerns new synergistic compositions for the treatment of trace element deficiencies in plants, containing a nitrate of the metal corresponding to the deficiency needing treatment, an alcohol acid or diacid, at least partly soluble in water, or an alkaline metal salt of these acids, and an organic sulphoxide of the formula ##EQU1## where R.sub.1 and R.sub.2 represent hydrocarbon groups with 1 to 12 carbon atoms, in particular dimethylsulphoxide.These compositions provide an effective treatment to cure trace element deficiencies, in particular iron or magnesium deficiencies, in a wide range of different plants, without producing any phytotoxic side-effects.

Abstract: A recording apparatus for recording digital signals corresponding to components of telluric and magnetic fields. The apparatus comprises an analog input stage, a low pass filter stage, an analog output stage, an analog multiplexer and an analog-to-digital converter and recording system for recording the digital signals. A gain computing module is provided as well as a recording selector to achieve variable amplification gains in the analog input and output stages as well as variable frequency bands in the low pass filtering stage to accommodate different frequency input signals for low frequency recording, intermediate frequency recording and high frequency recording.

Abstract: This invention concerns a device for emitting mechanical waves in an external medium.This device comprises an annular or axial combustion chamber, shut by a valve, and comprising means of introducing fuel and oxidant, and an ignition system; the valve is composed of a differential piston, one side of which forms a mobile wall of a chamber containing fluid under pressure, and part of the other side of which forms a mobile wall of the combustion chamber.This device is used mainly to generate compression waves for the purpose of seismic exploration.

Abstract: This invention concerns an appliance for measuring pressures, particularly those above 5,000 bars.This appliance comprises in combination, a manometric gauge and a dynamometric ring equipped with stress gauges, the section of the ring being such that its deflection does not exceed 0.13% of the elastic limit of the steel.This appliance has the same characteristics as a manometric gauge, but its compactness, lightness and ease of handling mean that it can be used both in the laboratory and in industrial installations.

Abstract: Process for dispersing molten sulphur in a hydrocarbon material, such as asphalt, tar and more particularly bitumen. The dispersion is effected in such a way as to produce an emulsion of sulphur in very fine particles, with dimensions not exceeding 10 microns, in the hydrocarbon material. A turbine with a gap or clearance of about 0.1 to 2.25 mm. is very useful for this purpose. The emulsions obtained are particularly suitable for road surfaces.

Abstract: In a continuous process for the selective absorption of constituents from a gas stream where a component is reacted to form absorbable constituents, recovery per unit volume of absorbent is improved by passing the gas through a low temperature mass absorption zone, a high temperature reaction-absorption zone and a final low temperature absorption zone, the absorption solution from the final absorption and reaction-absorption zones being combined to form the absorption solution of the mass absorption zone.

Abstract: Enzymes are fixed to cellulose containing 5 to 25% lignin to form an enzyme-cellulose complex by a process involving treating cellulose pieces with an alkaline solution to remove lignin on the surface of the pieces, treating the resultant cellulose pieces with a sulfochlorinating or a chlorinating agent in an excess of pyridine until sulfur and/or chlorine is combined with the cellulose, washing the sulfur and/or chlorine-containing cellulose pieces and treating the pieces with an aqueous enzyme solution to attach enzymes thereto. A very important application is preparation of a rennet-cellulose complex and using the complex for coagulating milk in making cheese.

Abstract: An improved process for purifying gas containing hydrogen sulphide and possibly other acid impurities, by means of amines, consisting of absorption of these impurities by contact between the gas for purification and an amine solution, particularly a mono- or di-ethanolamine solution, steam regeneration of the amine solution after it has fixed the acid compounds, and recycling of the regenerated solution to the absorption zone, characterized by the fact that the sulphur content of the regenerated amine solution is kept at an optimum level by varying the flow of regenerating steam.This improved process ensures better elimination of acid compounds, particularly hydrogen sulphide, by means of amines, and keeps the cost of purification as low as possible.

Abstract: A process for automated regulation of a unit producing sulphur by oxidation of hydrogen sulphide, in which the flow of gas carrying oxygen into the unit is regulated so as to keep an operating parameter, based on measurement of the sulphurous compound of the residual gases, level with a reference value.It is characterized by the fact that the control signal, used to regulate the flow of gas containing oxygen at the unit inlet, is a combination of a signal based on measurements taken at the inlet, and representing the theoretical flow of this gas needed to keep the operating parameter at its reference level and another signal representing the correction needed in this flow to adjust the instantaneous value of the parameter to the reference level.This process allow better control of the sulphur unit, with increased efficiency and reduced atmospheric pollution.