摘要:
A balanced gyrator comprises interconnected pairs of single-ended inverting class AB transconductors (TC1 to TC4) fabricated from MOSFETs together with common mode feedback circuits (26) connected between balanced inputs (18, 19) and outputs (22, 23). Peaking of the frequency response resulting from distortion due to the creation of a high frequency parasitic feedthrough path in the transconductors is overcome by the provision in each of the transconductors (TC1 to TC4) of a non-reciprocal feedback capacitance (Cf) which renders the feedthrough capacitance reciprocal thereby neutralising the feedthrough capacitance of the gyrator. The devices include a filter (FIG. 8, not shown) and a transceiver (FIG. 10, not shown).
摘要:
An current mode analogue-to-digital converter uses a conversion stage which operates using a two-phase clock and which requires the input signal to be present during only one of the phases. A sample-and-hold circuit (120, 130, 135) samples the input signal during the first clock phase and during the second clock phase a quantised bit value is generated from a mirror of the held input current by a kickback-free comparator circuit (140). Also during the second clock phase a residue is generated using the quantised value and a non-mirrored version of the held input current. Optionally, two comparator circuits (140, 140″) may be used to provide two-level quantisation, enabling errors introduced by the current mirror to be corrected by a Redundant Signed Digit algorithm. Two pipelines of conversion stages (Si′ Si″ can be multiplexed to double the conversion rate.
摘要:
An insertable progressing cavity pump is taught. The pump is insertable in a bore of a tubing string by carriage on a drive string, the insertable progressing cavity pump includes a stator, a helical rotor locatable in the stator and including a coupling for connection to the drive string, a tubular housing for accommodating the stator therein and sized to be insertable into the tubing string, a pump hold-down arrangement in communication with the housing and disposed above the stator for engaging the pump into the tubing string, and a torque transmitting arrangement acting between the rotor and the housing to transmit torque from the rotor to the housing in both the clockwise and counter-clockwise direction, when the housing is carried on the drive string. The insertable progressing cavity pump in another aspect includes a hold down assembly disposed above the stator on the pump housing.
摘要:
A baggage chute for transferring baggage from an elevated level of an aircraft passenger boarding bridge to ground level. The chute includes at least one slide member which is shaped to form a truncated cylinder of arcuate cross-section and which has annularly extending ribs. A plurality of mounting members are used to fasten the slide member to the boarding bridge and to support the slide member. A baggage receiving area is attached near an end of the slide near ground level for receiving and retaining baggage. The receiving area includes a flexible member extending substantially across the receiving area for stopping the sliding of the baggage and which absorbs the impact of the baggage.
摘要:
An animal litter including an extruded smectite clay that forms stronger clumps, when wetted with animal urine, due to the extrusion process. In a preferred embodiment, the extruded smectite clay is mixed, before or after extrusion, with a small percentage, preferably at least about 0.025% to less than 0.1%, based on the dry weight of the smectite clay, of a water-soluble adhesive that forms improved, stronger, more cohesive clumps that can be essentially completely removed from a litter box leaving the remaining litter box contents odor-free.
摘要:
A method of treating a water-swellable clay after the clay has been mined and dried to improve its properties when in contact with salt-contaminated water. After the common initial drying of the clay to a moisture content of 12% by weight or less, the clay is rewetted to a moisture content of more than 12% by weight, preferably at least about 15% or more, based on the dry weight of the clay, then redried to a moisture content of 12% by weight or less, based on the dry weight of the clay. This rewetting and redrying processing of a dried clay unexpectedly improves the salt water absorbency, and viscosity properties when the clay is in contact with salt-contaminated water; unexpectedly increases the rheology properties of the clays for oil well drilling fluids and lost circulation fields when salt-contaminated water is encountered during drilling, as a suspending agent in the cosmetics and pharmaceutical industries when the composition contains a dissolved salt; and provides unexpectedly increased salt water-absorption in forming water-swellable clay-based water barriers.
摘要:
A method of treating a water-swellable clay, initially having a Fe.sup.+3 /Fe.sup.+2 ratio of at least 1.0, preferably at least 3.0, and most preferably in the range of about 5.0 to about 15.0, after the clay has been mined and dried. After the common initial drying of the clay to a moisture content of 12% or less, the clay is re-wetted to a moisture content of more than 12% by weight, preferably at least about 15% or more, based on the dry weight of the clay, then re-dried to a moisture content of 12% by weight or less, based on the dry weight of the clay. This re-wetting and re-drying processing of a dried clay unexpectedly improves the water absorbency, and viscosity properties; increases the effectiveness of the clays as binders in sand molds and iron ore pelletizing; unexpectedly increases the rheology properties of the clays for oilwell drilling fluids, and lost circulation fluids, and as a suspending agent in the cosmetics and pharmaceutical industries; improves the binding characteristics of the clays to act as a binder for iron ores, such as taconite, and sand molding (foundry industry); and provides unexpectedly increased water absorption in forming water-swellable clay-based water barriers.
摘要:
A method of treating a water-swellable clay after the clay has been mined and dried to improve its properties when in contact with salt-contaminated water. After the common initial drying of the clay to a moisture content of 12% by weight or less, the clay is rewetted to a moisture content of more than 12% by weight, preferably at least about 15% or more, based on the dry weight of the clay, then redried to a moisture content of 12% by weight or less, based on the dry weight of the clay. This rewetting and redrying processing of a dried clay unexpectedly improves the salt water absorbency, and viscosity properties when the clay is in contact with salt-contaminated water; unexpectedly increases the rheology properties of the clays for oil well drilling fluids and lost circulation fields when salt-contaminated water is encountered during drilling, as a suspending agent in the cosmetics and pharmaceutical industries when the composition contains a dissolved salt; and provides unexpectedly increased salt water-absorption in forming water-swellable clay-based water barriers.
摘要:
An article of manufacture including an elongate confined mass of a water-swellable clay for sealing joints or seams between adjacent water-barrier materials or for plugging defects or other unsealed areas adjacent to a water-barrier layer. The elongate, confined mass of water-swellable clay is manufactured in any desired cross-sectional shape or configuration e.g. circular, eliptical, rectangular, square, and the like and can be manufactured in roll form for dispensing individual confined masses of water-swellable clay individually. The water-swellable clay is confined within a layer of material that permits the entrance of water to contact the water-swellable clay for hydration of the clay, such as by being water-porous or water-soluble and such that upon sufficient hydration of the confined mass of water-swellable clay, the confining layer will dissolve sufficiently, burst or tear to permit relatively free movement of the hydrating and expanding water-swellable clay.
摘要:
A method of improving the crop yield of transplanted crops and of extending the useful life of freshly cut plants utilizing an aqueous gel including a highly absorbent, crosslinked, mixed salt of homopolymerized or copolymerized acrylic acid. The aqueous gels utilized in the present invention not only show improved crop yield and extended plant life in the absence of plant nutrients, but also exhibit sufficient gel strength and rigidity to support the plants in the absence of inert solid aggregates.