Abstract: A method of attaching a pre-sintered body of polycrystalline diamond material to a substrate along an interface therebetween, the substrate being formed of cemented carbide and a metal binder phase dispersed therein, comprises placing a layer comprising one or more elements or alloys thereof on the interface on one or other of the body of polycrystalline diamond material or substrate; the one or more elements being selected to form a eutectic mixture with the metal in the binder phase, the eutectic mixture having a lower melting point than the melting point of the metal in the binder phase of the substrate.

Abstract: A method of forming a lapping plate. The method includes providing a lapping plate having a surface, spraying an adhesive onto the surface, spraying a slurry of abrasive particles and solvent onto the adhesive, and curing the adhesive to form an abrasive coating on the lapping plate. The adhesive may be, for example, epoxy, and the abrasive particles may be, for example, diamonds.

Abstract: An abrasive article includes abrasive particles contained within a hybrid bond that may include a metal bond material and an organic bond material, the article having an average thickness of 250 microns or less and the metal bond material including a solid solution phase and an intermetallic phase distinct from the solid solution phase.

Abstract: An abrasive article has an abrasive portion and chopped strand fibers (CSF) with enhanced strength and/or fracture of toughness. The CSF may be coated with a thermoplastic having a loss on ignition of at least about 2 wt %. The CSF can have a primary coating and a secondary coating on the primary coating. At least some of the CSF can have a length of at least about 6.3 mm.

Abstract: An abrasive article has an abrasive body with an axis and an axial thickness AT of not greater than about 10 mm. The abrasive body may include an abrasive matrix comprising an organic bond and abrasive particles, as well as a reinforcement of discontinuous fibers.

Abstract: An abrasive article has an abrasive portion with an organic bond and abrasive particles. The abrasive article has a non-abrasive portion (NAP) mounted to the abrasive portion. The NAP includes molding compound (MC) having chopped strand fibers (CSF). The CSF can be coated with a thermoplastic coating having a loss on ignition (LOI) of at least about 2.4 wt %, and the NAP having no abrasive particles. The NAP can include an MC having no abrasive particles with a MOHS scale hardness of at least about 9. The NAP may include CSF coated with a primary coating and a secondary coating on the primary coating. The NAP may have an outer diameter that is at least half of but not greater than an outer diameter of the abrasive article.

Abstract: A cubic boron nitride complex polycrystal contains granular cubic boron nitride and tabular cubic boron nitride. The average grain size of the granular cubic boron nitride is 500 nm or less. The maximum value of a short side of the tabular cubic boron nitride is 10 nm or more to 10000 nm or less. Thereby, it is possible to provide a cubic boron nitride complex polycrystal having high hardness and a manufacturing method therefor, a cutting tool, a wire-drawing die and a grinding tool including the same.

Abstract: The present invention is directed to a method for producing a slurry used in a wire saw, including: re-pulverizing with a jet mill part or all of the abrasive grains pulverized with a roller mill or a ball mill such that the abrasive grains have an average circularity of 0.900 or more; and blending the abrasive grains whose the average circularity is 0.900 or more with a coolant to produce the slurry, and to a slurry including blended abrasive grains having an average circularity of 0.900 or more. The invention enables suppression of reduction in slicing capability due to reduction in abrasive-grains concentration and of increased costs due to reduction in slicing quality and in productivity, even when abrasive grains having a grain diameter smaller than that of #2000-size abrasive grains are used to reduce a kerf loss.

Abstract: A shaped abrasive particle having a major surface-to-side surface grinding orientation percent difference (MSGPD) of not greater than about 35%.

Abstract: A coated abrasive article including a plurality of shaped abrasive particles overlying a backing, the coated abrasive article having a plain-carbon steel grinding lifespan of at least about 5500 g/in.

Abstract: The present invention is directed towards a dock ramp assembly (100) for a docking ope (104) on a facility; the dock ramp assembly comprising a seal for sealing the docking ope with at least one access door ope on a transport vehicle when the transport vehicle is docked with the facility; the seal comprising an upper seal (504) which extends over a top peripheral edge (106) of the docking ope (104) and adjacent side peripheral edges (110A, 110B) of the docking ope, and, a lower seal (600) which extends beneath the lower peripheral edge (108) of the docking ope, such that the seal extends around the entire periphery of the docking ope (104) and the seal is arranged to form a complete seal between the docking ope and the access door ope when the transport vehicle is docked with the facility; wherein, the dock ramp assembly (100) further comprises a retractable bumper (124A, 124B) which is transitioned from an extended, in-use position in front of the docking ope, to, a retracted, stored position remote from the

Abstract: A superstructure for a railcar comprising at least a first side assembly, a roof extending from the first side assembly and being comprised of at least a first top chord extending inwardly and upwardly from the first side assembly and a first top chord stiffener comprised of at least a first leg and a second leg. The first and second legs are disposed at a right angle to each other, and the first top chord stiffener is attached to the first top chord and the first side assembly.

Abstract: A tensegrity structure with one or more tensegrity units formed by a membrane in combination with three or more elongate compression members obliquely disposed in a spiral relationship in compression within the membrane. The ends of the compression members within each tensegrity unit and in adjacent tensegrity units are spaced from one another, and the compression members of adjacent tensegrity units overlap along a longitudinal dimension. The membrane forms anticlastic curves and has variable double curvature between ends of compression members. Multiple tensegrity units can form a column, which can be tapered, curved, or otherwise constructed.

Abstract: A data center includes a floor that supports rack computing systems and walls that enclose a computing room. The computing room holds the rack computing systems. One of the walls is a movable wall. The movable wall translates relative to the other walls to increase or decrease the size of the computing room.

Abstract: It is disclosed a densely packable sequential series of external housing units associated with succeeding internal housing units. The external housing units have inside volume and openings for receiving the internal housing unit. Means for facilitating the displacement of an internal unit out of an external unit, like integrated bearings, integrated wheels, integrated retractable wheels, and a low friction coating are installed on an inside shells of the associated external housing unit, on an outside shells of the internal housing unit. The housing units have a uniform cross section along a majority of one of the dimensions of the unit, having outlines like a circle, a triangular frame, a rectangular frame, a circular arc of a trapezoidal frame, a polygon of five, six or more edges, a hyperbolic arc, and a parabolic arc, or other types of arches. The typical transverse linear size of an internal unit is 80% to 99% of the preceding external unit.

Abstract: A portable modular building structure that includes a plurality of sections assembled adjacent one another. The sections include molded fiberboard panels, that optionally include interior plenums. In an embodiment, each panel has an upwardly curving profile, and mirror-image sections are attached to one another via a fastener, that may include tape or other mechanical fastener. The sections are positioned end to end, with the number of sections determining the overall length of the structure. An optional end section of the structure may include wedge shaped sections positioned end to end, forming a curved end.

Abstract: Negative stiffness systems and methods for seismic protection of a structure is described. A system can include a negative stiffness device having a first linkage pivotably connected to an anchor frame at a first pivot point and pivotably connected the movement frame at a second pivot point. The negative stiffness device can include a spring having a first end operably coupled to the anchor frame and a second end operably coupled to a movement frame. In a rest state, the spring can be compressed to exert a preload force to the first linkage and the anchor frame and not displace the first linkage and the movement frame. In an engaged state, the spring can be configured to apply a force to the first linkage such that the movement frame is displaced in a same lateral direction of a seismic load. The spring force can be amplified by the first linkage.

Abstract: A vertical wall mount system is provided that is easily installed in a perfectly level and plumb manner and is further cable of being design to be completely waterproof, interchangeable and customizable to include endless additional features. The vertical wall mount system includes two main components: a sub-frame assembly and a panel frame assembly. The sub-frame assembly includes mounting clips for pivotal attachment to a wall frame, such as, a standard 2×4 stud. Horizontal wall rails are mounted on the mounting clips to create the sub-frame assembly. The horizontal wall rails are designed to support a panel assembly on the horizontal wall rails, which may, for example, include a tile panel. The panel assembly includes a panel frame secured to the back side of the panel, which panel assembly is designed to hang on the horizontal wall rails of the sub-frame assembly.

Abstract: A wall siding corner cover apparatus having an elongated length is provided. A corner portion is formed from first and second sides connected together at proximal ends of each of the first and second sides, wherein the first side is positioned substantially perpendicular to the second side. A first ending portion is connected to a distal end of the first side and a second ending portion is connected to a distal end of the second side. A first rear leg is connected to the first ending portion and a second rear leg is connected to the second ending portion. Each of the first and second rear legs extends towards the proximal ends of each of the first and second sides, respectively. Each of the first and second rear legs terminates in a position between the proximal and distal ends of each of the first and second sides, respectively.

Abstract: Disclosed herein are embodiments of foam backing panels for use with lap siding and configured for mounting on a building. Also disclosed are lap siding assemblies and products of lap sidings. One such embodiment of the foam backing panel comprises a rear face configured to contact the building, a flat front face configured for attachment to the lap siding, alignment means for aligning the lap siding relative to the building, means for providing a shadow line, opposing vertical side faces, a top face extending between a top edge of the front face and rear face and a bottom face extending between a bottom edge of the front face and rear face.

Abstract: A set of essentially identical panels (1, 1?), such as building panels, provided with a mechanical locking system including a displaceable tongue (30), which is arranged in a displacement groove with a first opening at a first edge of a first panel (1). The displaceable tongue is configured to cooperate with a first tongue groove (20), with a second opening at a second edge of an adjacent second panel (1?), for vertical locking of the first and the second edge. The height of the first opening is greater than a second height of the second opening.

Abstract: A floor covering formed by a plurality of panels each having two opposite edges arranged to couple adjacent panels to each other. The coupling parts include a tongue and a groove, as well as locking parts preventing the drifting apart of two such adjacent panels. A separately manufactured insert is provided between at least two of the coupled panels, and the tongue and groove. The insert comprises at least two portions functioning as fixed spacing elements with a first portion between the upper side of the tongue and the lower side of the upper lip, and a second portion between the locking parts.

Abstract: A modular building system including: assembled modules, where the modules provide framing for a structure; panels, where the panels are implemented within the modules to create a building structure; fixed hinges, where the fixed hinges are attached along the edges of the modules; and a series of hinge connectors throughout the structure, where the series of hinge connectors provide a mechanism for attachment of the modules to each other. The framework may include metal channels to adjoin the components of the framework. Each module may include a frame, an inner surface, an outer surface, insulation within the frame and a spacer between the inner surface and the outer surface.

Abstract: An apparatus for reinforcing a plurality of adjacent parallel spaced apart wooden structural members to each other. Each of the structural members extends between first and second ends and has first and second edges. The apparatus comprises a ridged member extending between first and second ends and having a length sufficient to extend between two adjacent structural members. The apparatus further comprises a socket at each of the first and second ends of the rigid member. Each socket has a central axis therethrough and is formed of a base panel and first and second side panels. The socket is adapted to engage with a socket of an adjacent rigid member so as to interlink successive rigid members across a plurality of structural members.

Abstract: A high-strength disengagement prevention pintle veneer tie and anchoring system employing the same is disclosed. The high-strength veneer tie utilizes modified compressed wire formatives formed from a wire formative construct that is cold-worked, with the resultant body having substantially semicircular edges and flat surfaces therebetween. The edges are aligned to receive compressive forces transmitted from the outer wythe. The veneer tie hereof, when part of the anchoring system, interengages with wall anchor and is dimensioned to preclude veneer tie movement and pullout through the use of the U-shaped securement portions. The veneer tie is installed within the wall anchor through a swinging motion, in either an over and through or under and through the anchor installation, fully securing the veneer tie within the anchor and providing flexibility during installation.

Abstract: The present invention discloses a unitized precast grillage foundation for supporting a structure comprising: a plurality of anchoring elements defining a grid for resting on an underlying surface; a base connected on the grid, the base comprising at least a first footing and a second footing spaced apart and at least one connecting member between and connected to the at least first footing and the second footing; and a beam-column projecting upwardly from the base, and a method of making same.

Abstract: A splice sleeve having an elliptical or compound curve cross section for connecting overlapping end portions of reinforcing bars utilized in various types of structures in which steel reinforcing bars are utilized and it is desired to connect the overlapping end portions of the reinforcing bars. The splice sleeve is configured to receive the overlapped end portions of the reinforcing bars and then be filled with hardenable material to resist axial tension and compression exerted on the reinforcing bars. In one embodiment, both ends of the sleeve are provided with an inwardly directed lip to increase the splicing capacity of the sleeve and also to serve as a guide to position the rebars to a minimum of about 3 mm from the inside wall surface of the sleeve.

Abstract: A buckling restrained brace comprises a core member, core restrainer member sections and a jacket member. The core member has two opposite ends. The core restrainer member sections are configured to be arranged around the core member. The jacket member comprises fiber reinforced polymers configured to be wrapped around the core restrainer member sections and core member to couple the core restrainer member sections to the core member such that the core restrainer member sections and jacket member cooperate to provide greater resistance to buckling of the core member when the brace is subjected to compression. In some implementations, the brace has a weight less than about 50% of a weight of a conventional buckling restrained brace of similar length and having a steel core and mortar-filled tubular core restrainer member of comparable cross-sectional areas, respectively.

Abstract: A method for packing a mattress spring bed includes: A. overlaying at least two mattress spring beds onto each other to form a mattress spring bed stack, the top side and the bottom side of the mattress spring bed stack are a mattress frame or a rigid support frame; B. placing the mattress spring bed stack into a sealing bag, then vacuuming the sealing bag, resulting in the springs of the spring beds being compressed; C. binding the mattress spring bed stack by strap. The mattress spring bed stack has a small volume, thus reducing the occupied space, increasing the transportation efficiency, and effectively reducing manufacture cost. In addition, the top side and the bottom side of the spring bed stack are respectively a mattress frame or a rigid supporting frame.

Abstract: Banknote processing equipment is disclosed, which comprises a chamber having an open end for insertion of a bag into the chamber and an extractor adapted to establish a lower ambient pressure between the chamber and the bag to that within the bag to cause the bag to expand into an open configuration during a banknote filling operation, whereby the banknote processing equipment can deposit banknotes in the bag.

Abstract: Packing tray for protecting fragile and perishable food items, such as pears, which allows fruit items of varying dimensions and weights to be held securely in each pocket, and which allows a plurality of stacked trays and fruit to be packaged in boxes (e.g., standard carton sizes). The tray is a plastic foam sheet having a top wall and a plurality of recessed cell pockets, each cell pocket having a relatively thinner cell sidewall with expandable (accordion-like) flutes, and a relatively thicker bottom wall also with expandable flutes. This construction allows the cell bottoms in adjacent pockets and in adjacent trays of the stack to move relative to one another to accommodate various sizes and weights of fruit while still protecting the fruit from damage.

Abstract: An extraction system is designed for metal working and other applications. The system may comprise a blower that delivers a positive pressure airflow to a hood that creates an air region for removal of airborne components from a work area. The blower is driven by a three-phase motor in a portable base unit that may be plugged into a source of three-phase power. A rotational direction reversing switch is provided between the motor and a three-phase plug to permit reversal of the rotational direction of the motor when the motor is determined not to rotation in the intended direction when the plug is connected to a receptacle. The switch may be manual or automatic.

Abstract: Provided is a method of fabricating a filter medium including the following steps. An assembly of first fiber is formed by a first spinning device. A plurality of second fiber is formed by a second spinning device. On a reception device is collected a film having a three-dimensional non-woven structure constructed by the first fibers and the second fibers. Each of the first fibers has a diameter of 1-50 ?m. Each of the second fibers has a diameter of 1-1000 nm. The second spinning device is positioned between the first spinning device and the reception device. The first fibers and the second fibers stack with each other in a random manner to form the three-dimensional non-woven structure.

Abstract: An air filter and carburetor arrangement includes a round filter and a round filter carrier having a filter plate. The round filter has a central filter axis, which lies at an angle to the filter plate. The carburetor has a carburetor body, in which an intake duct is configured with a duct longitudinal axis, and at one end of the intake duct on the carburetor body a filter connection side for the round filter carrier is configured, wherein the round filter carrier is fixed with at least one surface portion of the filter plate on the connection surface of the carburetor. The design is provided such that the duct longitudinal axis of the intake duct lies in the plane of the filter plate at a lateral distance (r) to the filter axis of the round filter fixed to the round filter carrier.

Abstract: The inertial particle separator with heat exchange is a system for separating particulate matter from a mixture of fluid and particles, such as, for example, oil mixtures, natural gas mixtures, or combinations thereof. A rotating pipe first receives the mixture and imparts a tangential velocity thereto. A first heat exchanger is in thermal communication with the rotating pipe for decreasing the temperature of the mixture. An inlet of a convergent-divergent nozzle is connected to an outlet of the rotating pipe for receiving the mixture. The convergent-divergent nozzle accelerates the mixture to a supersonic axial velocity. The accelerated mixture flows into a temperature-controlled pipe which is in thermal communication with a second heat exchanger for further decreasing the temperature of the mixture. The mixture then flows into a concentric diffuser, such that the particulate matter of the mixture is separated from the fluid of the mixture under centrifugal force acting thereon.

Abstract: The present invention discloses a suspended ceiling filtration apparatus, which includes filtration units. The filtration unit includes a filtration part, two horizontal strip support legs and two longitudinal strip support legs. A support plate protrudes from the support legs. The filtration part is placed on the support plate, and a buffer filling part is disposed between the filtration part and the support plate. The buffer filling part is utilized to self-adaptively swell and shrink relative to the support plate according to a weight of the supported filtration part, the buffer filling part fills a gap between the support plate and the filtration part.

Abstract: A drive coupler (102, 104) for coupling a reciprocating knife (106) to a drive member (112, 114) is provided, wherein the reciprocating knife (106) includes at least one elongate bar (120, 122, 180, 182) having a longitudinal extent and fixed to a plurality of blades (138), wherein the at least one elongate bar (120, 122, 180, 182) is supported on support members (140) that constrain the at least one elongate bar (120, 122, 180, 182) to reciprocate in a direction generally parallel to the longitudinal extent of the at least one elongate bar (120, 122, 180, 182), the drive coupler (102, 104) comprising: a first elongate strap (146, 162) configured to be attached to the at least one elongate bar (120, 122, 180, 182); a second elongate strap (146, 162) configured to be attached to the at least one elongate bar (120, 122, 180, 182); and a means (152, 164, 187, 189, 193, 200) for (i) flexing the first elongate strap (146, 162) with respect to the second elongate strap (146, 162), (ii) for flexing the first elongat

Abstract: In a work vehicle, because of growing need to equip a DPF for exhaust gas countermeasures near an engine and a request of increasing the size of a fuel tank, a system including the fuel tanks provided below a floor step and on left and right sides of a transmission case has been employed. However, when a lawn mower is installed between front wheels and rear wheels, an increasing width of a vehicle body becomes a problem. To solve the problem, a locus of the raising and lowering operation of a lawn mower 5 is specified by a parallel link formed of left and right front links 43, 43 and left and right mid links 45, 45, and in a work vehicle where the lawn mower 5 is freely raised and lowered, the left and right mid links 45, 45 are respectively disposed between a transmission case 3 and fuel tanks 16L, 16L.

Abstract: A narrow row head unit may include a back plate secured to a left gearbox and a right gearbox, which gearboxes may be positioned adjacent one another. Each gearbox may provide rotational power to a pair of stalk rolls and a drive sprocket for a gathering chain. A right mounting tab may be secured to the back plate and the right gearbox, and a left mounting tab may be secured to the back plate and left gearbox. A right plate and leg may extend outward from the back plate adjacent the right mounting tab and a left plate and leg may extend outward from the back plate adjacent the left mounting tab. A narrow row head unit positioned left-of-center on a header may have the gathering chain positioned substantially over the right plate, and right-of-center substantially over the left plate.

Abstract: A harvesting header includes a header frame, a flexible cutterbar assembly, and a draper assembly. The cutterbar assembly is mounted to the header frame and includes a plurality of skids. Each of the skids has a lower margin configured to engage the ground such that the skids cooperatively cause flexing of the cutterbar assembly along the length thereof in response to changes in terrain as the header is advanced. Each skid presents a skid surface extending from the lower skid margin.

Abstract: A harvesting header bat having a channel for removably receiving alternating quick-release fingers and spacers is provided. The spacers are capable of production in different lengths to support different applications of the harvesting header. The quick-release finger is provided with projections configured for mating with flanges at the channel opening, enabling the finger to be inserted into the channel in a first orientation and then rotated into a second orientation to engage the flanges and releasably lock the finger in place. The spacers are also configured to engage the flanges of the channel and may be provided in different lengths where a particular harvesting header application requires a certain distance between fingers on the bat.

Abstract: With a wire rope comprising at least one plastic core (11) and a number of wire strands (15) twisted around the latter a helical groove (20) is respectively produced by machining around the periphery of the plastic core (11) for each wire strand (15). The cross section of these helical grooves (20) is respectively matched to the outside diameter of the wire strands (15). The plastic core (11) is provided with the helical grooves (20) for receiving the wire strands (15) by this machining directly before the wire strands (15) are wound onto said core. By thus forming the wire rope by means of this machining in order to produce helical grooves of the plastic core, optimal guiding of the wire strands in the twisted state is achieved, and so overall there are improvements to the properties of the wire rope.

Abstract: The power conducting device includes at least one first and one second line guiding device. The power conducting device has a first guiding channel and a second guiding channel which can be twisted about a common axis. The first line guiding device is arranged in the first guiding channel and the second line guiding device is arranged in the second guiding channel. The line guiding devices in each case have an end member and a connecting member, the end member being connected either to a respective inner ring or outer ring, and the connecting member being connected to the respectively other outer ring or inner ring.

Abstract: A system for reducing emissions includes a gas production source that produces nitrogen oxides, sulfur oxides, hydrogen sulfide, sulfuric acid, nitric acid, formaldehyde, benzene, metal oxides, or volatile organic compound emissions. An exhaust plenum is downstream from the gas production source, and structure for dispersing a solvent is in the exhaust plenum. A collection tank is in fluid communication with the exhaust plenum to receive the solvent from the exhaust plenum, and a heat source is in the exhaust plenum downstream from the structure for dispersing the solvent. A method for reducing emissions from a gas production source includes flowing exhaust gases through an exhaust plenum, dispersing a solvent through a nozzle in the exhaust plenum, collecting the dispersed solvent in a collection tank, and heating the exhaust gases flowing through the exhaust plenum downstream from the nozzle.

Abstract: A hybrid electric rotary engine is provided having a pair of rotors separated by a divider and configured for rotation in opposite directions, a timing gear engaged between the inner faces of the rotors, and at least one pair of slanted rotor openings in the rim of each rotor for alignment with at least one pair of slanted divider openings to form a pair of combustion chambers in communication with at least one pair of exhaust chambers for venting of exhaust and to provide rotational thrust.

Abstract: A jet engine includes at least one oil separator, through which an air-oil volume flow can be guided out of several areas supplied with oil for separating the oil, where a device for spraying oil into the air-oil volume flow is provided. Oil can be sprayed in using the device in the area of each connection between an area supplied with oil and the oil separator and/or downstream of a combining area between at least two air-oil volume flows from two or more areas supplied with oil.

Abstract: A system for detecting airfoil clashing within a compressor comprises a compressor having a row of rotor blades and an adjacent row of stator vanes, an acoustic emission detection system that generates an acoustic emissions signal, a rotor blade monitoring system that generates a blade pass signal, and a processing unit that is in electronic communication with the acoustic emission detection system and the rotor blade monitoring system. The processing unit is configured to fuse the acoustic emissions signal with the blade pass signal to provide a combined signal that is indicative of an airfoil clashing event between the rotor blades and the adjacent row of stator vanes.

Abstract: This is a system that stores energy by compressing atmospheric air and confining it in tanks or caverns, combining the thermodynamic cycle followed by the atmospheric air (Brayton cycle) with another thermodynamic cycle followed by an auxiliary fluid, that is confined in the same cavern within a membrane, following two sections of a Rankine cycle, one during the air compression and entry into the cavern process and the other during the air outlet and turbininig process, using heat from the exhaust gases from the turbine as a heat source for an additional Rankine cycle, and being able to use the tanks or caverns for making an extra constant volume heating of compressed air and I or of the auxiliary fluid

Abstract: The invention relates to a combined cycle power plant that includes, a gas turbine plant, a heat recovery steam generator heated by hot waste gases of a gas turbine plant, and a steam turbine plant driven by the steam produced, and a waste gas purification plant, arranged downstream of the heat recovery steam generator in which carbon oxides in the waste gases can be absorbed by an absorber fluid, which is subsequently regenerated at an elevated temperature in a regenerating section while giving up the carbon oxides for supplying to a storage. The regenerating section has a heater for maintaining a necessary elevated temperature for regeneration. The heater operates with steam from the heat recovery steam generator or from the steam turbine plant. The steam condenses and the resulting hot condensate can be supplied to a flash boiler where it, at low pressure, immediately at least partially evaporates.

Abstract: A Hall effect thruster including a downstream end of its annular channel presenting a cross-section that is variable to vary a thrust and a specific impulse of the thruster.