Abstract: Disulfonate salts of 2,4-pentanedione and methods for making such salts are described. The disulfonate salts are useful as cement dispersants. Cement compositions including such salts, methods for making cement compositions including such salts, and methods for performing cementing operations using such cement compositions are also described.

Abstract: Disulfonate salts of 2,4-pentanedione and methods for making such salts are described. The disulfonate salts are useful as cement dispersants. Cement compositions including such salts, methods for making cement compositions including such salts, and methods for performing cementing operations using such cement compositions are also described.

Abstract: A system and method for determining load on a downhole tool according to which one or more sensors are embedded in one or more components of the tool or in a material on one or more of the components. The sensors are adapted to sense load on the components.

Abstract: Methods and compositions for breaking treatment fluids utilized in the stimulation of a subterranean formation.

Abstract: A hydraulic circuit and method for operating a gripping mechanism according to which fluid is passed from a source to the device while some of the fluid is passed to a valve that is adjustable to control the amount of fluid passed to it and therefore the amount of fluid passed to the device.

Abstract: A heater unit for air handling equipment comprises a peripheral frame 2 across which a plurality of heater tubes 12 extend. The heater tubes 12 have reverse bends, and each extends from an inlet end 6 and an exhaust end 8 disposed on the same side 10 of the frame 2. Respective burner units are provided at the inlet ends of the heater tubes 4. The exhaust ends 8 open into a common manifold from which the combustion gases generated by the burner units are evacuated by means of a fan. The heater unit is suitable for installing in air handling equipment, for example to replace steam or electric heaters, with the frame 2 then serving as part of the ducting of the air handling equipment.

Abstract: A system and method of optical switching utilizing a reflection device, the switch is disclosed. The system can include: an optical transmission path having an optical transmission medium, an input-side end and a first and a second output-side end; a radiation source associated with said input-side end for emitting a primary optical signal being coupled into said transmission path; a reflection device with the ability to be turned on and off selectively for receiving the primary optical signal and converting the primary optical signal into a secondary, modulated optical signal being reflected and coupled back into the second output-side end when the reflection device is on and wherein the primary optical signal is coupled into the first output-side end when the reflection device is off. The optical switch can contain mirrors that turn on and off, or are fixed in place while the switch is movable.

Abstract: A method and an apparatus are provided for matching the response of hydrophones 22 to the response of geophones 24 and significantly reducing response variations between hydrophones caused by inherent characteristics. The method includes the steps of determining a capacitance 66 for each of the hydrophones 22 in an operating environment, configuring a filter 36 based on the capacitance 66, and modifying a response of a channel of the hydrophone 22 using the filter 36. The apparatus includes an acquisition unit 20 having a geophone 24 and a hydrophone 22, a recording unit 30, a processing unit 31 and a filter 36 for correcting for variation between hydrophones 22 and changing a first order low frequency response of the hydrophone 22 to appear like a second order response like that of the geophone 24.

Abstract: A fluidized bed combustion system and method in which a recycle heat exchanger is disposed integrally with the furnace of a fluidized bed combustor. The recycle heat exchanger includes a plurality of stacked sections for receiving the recycled solids and are arranged in such a manner that the recycled solids are introduced into an upper level of the sections and pass through these sections to a lower level of sections before returning to the furnace. A portion of the stacked sections contain heat exchange surfaces for removing heat from the solids therein while another portion does not. The solids in the various sections are selectively fluidized to control the flow of the solids through the sections to control the temperature of the solids accordingly.

Abstract: A rail fastener for fastening rails to a support structure, particularly adapted for use in switches, crossovers, frogs and the like where a track plate must support a pair of closely spaced or nonparallel rails. The rail fastening includes a rigid track plate to which the rail is adjacent and two fastener pads laterally spaced on the track plate and disposed between the track plate and the support structure. Each fastener pad has a rigid member and a resilient member bonded together and two pins to join the elastomeric member to the track plate.