Abstract: The present invention relates to a turbomachine rotary-fan blade (2), comprising a body (20) made of a composite material, a metal reinforcement part (3) comprising a metal upstream nose (31), characterised in that the metal upstream nose (31) comprises, at least on the metal part (27b) of the blade tip, a recess (4) of longitudinally tapering thickness (AX), delimiting on the metal part (27b) over a height (H) at least one metal projection (5) with prescribed wear, which has a longitudinally tapering thickness and which is configured to detach at least partially in the presence of tangential friction in the second thickness direction (EP) against the metal part (27b), the recess (4) and the metal projection (5) with prescribed wear extending the first metal fin (32) and/or the second metal fin (33) and/or the upstream edge (22) of the body (20) made of composite material.

Abstract: A middle petroleum distillate composition containing a major proportion of middle petroleum distillate and a minor proportion of an additive in a sufficient amount to limit the settling speed of paraffins contained in said middle distillate. Said additive consists of a product resulting from a reaction between at least one aliphatic dicarboxylic compound and at least one primary amine functional compound of general formula (I), wherein R1 is a monovalent saturated aliphatic radical, Z is selected from —NR?— groupings in which R? is a hydrogen atom or a monovalent saturated aliphatic radical, n is an integer between 2 and 4, and m is an integer between 1 and 4; said primary amine functional compound being used in a ratio of 0.3-0.8 mols per mol of said dicarboxylic compound.

Abstract: A middle petroleum distillate composition containing a major proportion of middle petroleum distillate and a minor proportion of an additive in a sufficient amount to limit the settling speed of paraffins contained in said middle distillate. Said additive consists of a product resulting from a reaction between at least one aliphatic dicarboxylic compound and at least one primary amine functional compound of general formula (I), wherein R1 is a monovalent saturated aliphatic radical, Z is selected from —NR′— groupings in which R′ is a hydrogen atom or a monovalent saturated aliphatic radical, n is an integer between 2 and 4, and m is an integer between I and 4; said primary amine functional compound being used in a ratio of 0.3-0.8 mols per mol of said dicarboxylic compound.

Abstract: The process of butene-1 production comprises the steps of: a) sending a inhibited catalyst containing reactor effluent to a flash section where the pressure is decreased by about 0.1 MPa to about 2 MPa, and obtaining a first gaseous phase containing ethylene and butene-1 and a first liquid phase containing the inhibited catalyst; b) sending the first liquid phase from step a) to at least one vaporisation section which allows the separation of a second gaseous phase containing butene-1 and ethylene from a second liquid phase containing the inhibited catalyst; c) sending the second liquid phase from step b) to at least one thin film evaporation section which allows the separation of a third gaseous phase containing ethylene, butene-1 and some other heavier hydrocarbon products from a concentrated inactivated catalyst solution and, d) collecting the first, second and third gaseous phases to form a gaseous reactor effluent substantially free of spent catalyst.

Abstract: Compounds with general formula ##STR1## where R.sup.1 represents a hydrogen atom or a hydrocarbon group containing 1 to 40 carbon atoms. R.sup.2 represents a hydrogen atom or a hydrocarbon group containing 1 to 12 carbon atoms, A, B, and C, which may be identical or different, each represent a divalent hydrocarbon group containing 2 to 6 carbon atoms, n is a whole number from 5 to 50, m and p are each zero or a whole number from 1 to 25, and the sum n+m+p is a whole number from 5 to 50.These compounds are used in multifunctional additive compositions for fuels used in internal combustion engines, in particular spark ignition engines, in admixture with at least one compound selected from the group formed by detergent-dispersant compounds, and at least one compound selected from the group formed by mineral or synthetic lubricating oils and polyglycols which are soluble in said fuels.

Abstract: A C.sub.4 and/or C.sub.5 olefinic hydrocarbon cut, containing dimethyl ether and water as impurities, in a relative proportion of dimethyl ether to water of at most 5:1, is purified in a distillation zone where it is introduced at an intermediate level, distant from the top or from the bottom thereof by at least 3 theoretical plates, optionally with a stripping gas, and separated into a overhead fraction comprising an aqueous liquid phase and a hydrocarbon liquid phase at least partially recycled as reflux to the upper part of the distillation zone, and a bottom fraction formed of the purified C.sub.4 and/or C.sub.5 olefinic cut.

Abstract: Fluorinated impurities are removed from olefin oligomers by extraction with a solid adsorbent; the oligomers have been obtained from monoolefins having 2-4 carbon atoms, in the presence of a catalyst obtained by contacting a bivalent nickel compound with a hydrocarbyl aluminum halide and a trifluoroacetic acid.

Abstract: A process is provided for the production of nonenes or of a nonenes/dodecenes mixture, wherein: propylene is introduced into a liquid reaction phase containing a soluble dimerization catalyst, the temperature is 20.degree.-60.degree. C., at least a portion of the resultant hexenes is recycled and the propylene concentration is maintained between 0.05 and 1% by weight.

Abstract: Process for removing halogenated impurities from olefin oligomers by extraction with a polar solvent such as dimethylsulfoxide, acetonitrile, dimethylacetamide, dimethylformamide, diethylene glycol or dimethylsulfone.

Abstract: A process for treating an aqueous phase obtained by acidic or basic washing of a hydrocarbon phase comprising a soluble aluminum compound in solution, characterized in that it is neutralized at a pH of from 6 to 8.5, treated with an additive selected from the alkaline-earth metal oxides, hydroxides and carbonates, at a temperature ranging from 90.degree. C. to the boiling point, the molar ratio of the additive to aluminum being from 1/10 to 10/1, and separated thereafter from the insoluble phase of precipitate.

Abstract: A process for oligomerizing olefins uses a catalyst composition obtained by contacting (a) bivalent nickel compound with (b) a hydrocarbylaluminum compound of the formula Al R.sub.x X.sub.y where R is a monovalent hydrocarbon radical, X is halogen, x is from 1 to 1.5, y is from 1.5 to 2, x+y being equal to 3, and (c) a Bronsted acid consisting preferably of a halogenocarboxylic acid of the formula R.sub.1 COOH in which R.sub.1 is a halogenoalkyl radical of the formula C.sub.m H.sub.p X.sub.q X being halogen, m an integer from 1 to 3, p being zero or an integer and q being an integer, the condition p+q=2m+1 being fulfilled. A preferred Bronsted acid is of the formula R.sub.2 COOH in which R.sub.2 is a halogenomethyl group of the formula CX.sub.n H.sub.3-n, X being halogen and n an integer from 1 to 3.

Abstract: High-pass, low-pass and band-pass filters are obtained by combining switched-capacitance integrating networks.

Abstract: An improved catalyst composition is obtained by contacting at least one bivalent nickel compound with at least one hydrocarbyl aluminum halide, at least one Bronsted organic acid and at least one anhydride of a carboxylic acid. The composition can be used as a catalyst for olefin oligomerization.

Abstract: In a filter in which, in order to obtain the desired filter characteristic, a weighted sum of different signals is formed, it is proposed in accordance with the invention that for the formation of said sum means are employed which are constituted by capacitor circuits, which during a first time interval are each charged by said signals, and by a connection circuit for the formation, during a second time interval, of the equivalent of a single capacitor across whose plates the weighted-sum signal appears.The invention is used for the filtration of sampled analog signals.

Abstract: At least one of propene and butene is oligomerized, preferably dimerized, in an elongate cylindrical reaction zone. A recycle flow and the fresh feed charge are injected tangentially into said reaction zone. The catalyst preferably comprises a nickel compound and a hydrocarbyl aluminum halide.

Abstract: Catalyst composition for oligomerizing olefins, obtained by contacting (a) a bivalent nickel compound with (b) a hydrocarbylaluminum compound of the formula AIRCl.sub.2 where R is a monovalent hydrocarbon radical, and (c) a Bronsted acid consisting preferably of a halogenocarboxylic acid of the formula R.sub.1 COOH in which R.sub.1 is a halogenoalkyl radical of the formula C.sub.m H.sub.p X.sub.q, X being halogen, m an integer from 1 to 3, p being zero or an integer and q being an integer, the condition p+q=2m+1 being fulfilled. A preferred Bronsted acid is of the formula R.sub.2 COOH in which R.sub.2 is a halogenomethyl group of the formula CX.sub.n H.sub.3-n, X being halogen and n an integer from 1 to 3.

Abstract: Process for producing gasoline of high octane number from C.sub.3 and C.sub.4 olefinic cuts, such as those obtained by fractional distillation of a C.sub.3 / C.sub.4 catalytic cracking cut, comprising the steps of:(a) oligomerizing propylene of the C.sub.3 cut to obtain a first gasoline fraction,(b) reacting the isobutene of the C.sub.4 cut with methanol to produce methyl tert.-butyl ether which is separated from the unreacted C.sub.4 hydrocarbons to form a second gasoline fraction,(c) alkylating said unreacted C.sub.4 hydrocarbons with isobutane in the presence of an alkylation catalyst such as hydrofluoric acid, to form a third gasoline fraction, and(d) admixing, at least partially, said first, second and third gasoline fractions, so as to obtain gasoline of high octane number.

Abstract: High octane gasoline is obtained from C.sub.3 /C.sub.4 olefinic cuts by a combination of steps: oligomerization of the C.sub.3 fraction, hydroisomerization of 1-butene in the C.sub.4 cut, fractionation of the resultant C.sub.4 cut, hydrogenation of isobutene and alkylation. Resultant fractions are admixed to produce the desired high octane gasoline.

Abstract: Process for isomerizing 1-butene to 2-butene by contacting 1-butene, at a temperature from 50 to 140.degree. C, in the presence of hydrogen, with an isomerization catalyst containing a noble metal from group VIII of the periodic classification of elements, which catalyst was previously contacted with a sulfur compound at a temperature from 50 to 400.degree. C and then with hydrogen at a temperature of at least 50.degree. C.

Abstract: Process for manufacturing dicyclohexanol propane by hydrogenating, with molecular hydrogen, in the presence of a hydrogenation catalyst, diphenol propane dissolved in 2 ethyl-hexanol, adding water at the end of the reaction, distilling the reaction product and separating from the distillate an aqueous phase and a 2 ethyl-hexanol phase, the latter being reused as solvent for the reaction.