Abstract: A surface acoustic wave device includes at least one transducer; two acoustic reflectors disposed on either side of the at least one transducer so as to form a cavity, each acoustic reflector comprising an array of electrodes in the form of lines parallel with each other, each array comprising a subset of electrodes connected to a reference potential denoted mass defining a first connection type, and a subset of electrodes that are not connected to any potential, i.e. that have a floating connection defining a second connection type; at least one switching circuit configured to modify the distribution of the connections of at least one part of the electrodes of each array between the different connection types.

Abstract: Electroacoustic device having a transducer including a piezoelectric substrate, first and second electrodes of inverse polarity having respective first and second tracks provided on said substrate, the first and second tracks spiraling around a same center (C), the transducer being configured for generating a swirling ultrasonic surface wave in the substrate.

Abstract: Disclosed is a functionalizing method for the end functionalisation of trans-1,4 stereo-regular polydiene chains obtained by the coordination catalytic polymerisation of at least one conjugated diene monomer. It also relates to a polydiene having a trans-1,4 chain formation rate of at least 85%, preferably at least 90%, and an end functionalisation rate higher than 70%, preferably higher than 80%, and more preferably higher than 90%.

Abstract: Electroacoustic device that includes a body, an electrode to be electrically powered, named hot electrode, and an electrode to be electrically grounded, named ground electrode. The body includes a piezoelectric part or the electroacoustic device further including a piezoelectric part different from the body. The hot electrode includes a hot track spiraling around a spiral axis. The radial step between two consecutive coils of the hot track decreasing radially from the spiral axis. The hot electrode and the ground electrode are arranged on the piezoelectric part such as to define a wave transducer configured to generate a focalised ultrasonic vortex propagating in the body and/or, when a fluid medium is acoustically coupled with the electroacoustic device, in the fluid medium.

Abstract: An optical sensor, especially an artificial retina, that includes at least one photosensitive cell. Each cell includes a integration capacitor, a read circuit the operation of which depends on the charge of the integration capacitor, at least one MOS transistor operating subthreshold, and the drain-source current of which influences the charge on the integration capacitor, and at least one photodiode operating in photovoltaic mode and connected to the gate of this transistor, such that the drain-source current of the MOS transistor depends on the optical power received by the photodiode.

Abstract: A microstrip-type microwave sensor for the measurement of the dielectric properties of a solid or liquid material, constituted by a main line and two connected transmission lines integral at one of their extremities to the main line, the main line and two connected transmission lines being spaced from one another by a slot and being made integral with a substrate. The main line is connected to an electrical circuit by each of its two extremities to inject a sinusoidal signal, and wherein said main line has a width giving it an impedance in the range 50 Ohm, the two connected transmission lines being of the same width and of a length equal to one quarter of the wavelength guided in the substrate, the substrate having a height or thickness giving it flexibility or rigidity, the substrate being applied to a metallic support formed of a layer of metallic material.

Abstract: Treatment method for a rock formation against sand infiltration during production of fluid from this rock formation via a well drilled through said rock formation, comprising at least one step of injecting a geopolymer cement grout into said rock formation, in particular around the edges of said well and/or through said well.

Abstract: Method for increasing the ability of at least one droplet to slide over a medium. An ultrasonic surface wave is generated in the medium with a sufficient amplitude to cause the droplet to deform in an inertio-capillary eigen-vibration mode, thus decreasing the attachment of the droplet to the medium, so as to make it easier for the droplet to move under the effect of an external force, the amplitude of the ultrasonic surface wave being insufficient to cause the droplet to deform asymmetrically to the point that it moves in the absence of the external force in the direction of propagation of the ultrasonic surface wave.

Abstract: A method is for the preparation of furoic acid or of one of its derivatives of formula (I): in which R1, R2, R3 and R4 represent, independently of each other, a hydrogen atom, a linear or branched C1-C6 alkyl group, a —C(?O)—H group or a —COOH group, by heterogeneous catalytic oxidation of furfural or a derivative thereof of formula (II). The oxidation is carried out in the presence of a supported catalyst based on gold nanoparticles, and in a non-alkaline aqueous medium. A composition useful in the method includes at least furfural and supported gold nanoparticles.

Abstract: A method for generating a flow of fluid, implemented in a device including a membrane (2) provided with at least one hole (20) and elements (4) generating back-and-forth movements, wherein a flow is generated through the membrane by actuating the membrane, at least in the region of the at least one hole (20), according to a mode of deformation of the at least one hole, causing the at least one hole to open and close and disturbing the fluid in order to generate the flow. The device suitable for implementing the method is also described.

Abstract: A method is for the preparation of furoic acid or of one of its derivatives of formula (I): in which R1, R2, R3 and R4 represent, independently of each other, a hydrogen atom, a linear or branched C1-C6 alkyl group, a —C(?O)—H group or a —COOH group, by heterogeneous catalytic oxidation of furfural or a derivative thereof of formula (II). The oxidation is carried out in the presence of a supported catalyst based on gold nanoparticles, and in a non-alkaline aqueous medium. A composition useful in the method includes at least furfural and supported gold nanoparticles.

Abstract: The present invention provides a method (30) of determining mechanical properties of the pelvic cavity of a person or an animal, the pelvic cavity including a plurality of organs and the method comprising a step (34) during which pressure is measured at one or more points of the surface of one of the organs of said pelvic cavity, and during which, simultaneously, movements of a plurality of organs of said pelvic cavity are also measured. The present invention also provides a measuring device for measuring pressure in an organ of the pelvic cavity in order to perform the above method (30). The measuring device comprises an optical fiber pressure sensor mounted in a non-metallic housing, and a closed flexible reservoir mounted in said non-metallic housing and having a surface, in particular a flexible surface, that constitutes a pressure measuring surface.

Abstract: The present invention relates to the use of rhenium-containing supported heterogeneous catalysts for the deoxydehydration of glycerol to allyl alcohol, as well as to a process for the production of allyl alcohol from glycerol, in the presence of such heterogeneous catalysts.

Abstract: The present invention relates to the use of haloapatites as catalysts of the dehydration reaction of ?-hydroxylated carboxylic acids or acid esters, in particular of lactic acid or of methyl lactate, and also to a process for producing unsaturated carboxylic acids or acid esters, in particular acrylic acid or methyl acrylate, in the gas phase in a stainless steel reactor, in the presence of such a catalyst.

Abstract: The present invention relates to the use of molybdenum and vanadium mixed oxides, optionally iron doped, as catalysts for the oxidation of unsaturated alcohols, in particular allyl alcohol, and also to a process for the production of unsaturated carboxylic acids, in particular acrylic acid, in the gas phase, in the presence of such a catalyst.

Abstract: The present invention relates to the use of molybdenum and vanadium mixed oxides, optionally iron doped, as catalysts for the oxidation of unsaturated alcohols, in particular allyl alcohol, and also to a process for the production of unsaturated carboxylic acids, in particular acrylic acid, in the gas phase, in the presence of such a catalyst.

Abstract: Electroacoustic device having a transducer including a piezoelectric substrate, first and second electrodes of inverse polarity having respective first and second tracks provided on said substrate, the first and second tracks spiraling around a same center (C), the transducer being configured for generating a swirling ultrasonic surface wave in the substrate.

Abstract: A method for synthesising a second ester from a first ester, the method including the following steps: a) placing a first ester and a catalyst in the presence of dihydrogen such as to obtain a first alcohol and a second alcohol; b) extracting the second alcohol from the reaction medium; c) reacting the first alcohol with the catalyst of step a) in order to obtain a second ester and dihydrogen; and d) recirculating the dihydrogen obtained in step c) by injecting same into step a).

Abstract: A compound of the formula SbxFe1Oy (I) in which x varies from 0.4 to 1 inclusive and y varies from 1.6 to 4 inclusive, may be used as a catalyst for catalyzing the ammoxidation reaction of an alcohol of following formula (II) CH2?C(R1)—CH2—OH (II) in which R1 represents a hydrogen atom or a methyl radical, to give nitrile of following formula (III) CH2?C(R1)—C?N (III) in which R1 has the same meaning as in above formula (II), the said reaction being carried out in the gas phase, the said gas phase comprising at least oxygen and ammonia. The present invention also relates to the process for the ammoxidation of an alcohol of formula (II) employing a compound of formula (I) as catalyst.

Abstract: The invention relates to a miniaturized sensor having a heating element, and to an associated production method. The sensor includes a substrate, a cavity and a heat-insulating structure suspended above the cavity by areas connecting to the substrate. The heat-insulating structure includes at least two bridges extending above the cavity, the heating element being supported by said bridges, extending transversely thereto.