Abstract: A bypass blower provides air for combustion and scavenging purposes to a two-stroke diesel engine having an exhaust port from which an exhaust conduit ducts exhaust materials through a particulate trap and then to the atmosphere. An air atomizing nozzle is provided for introducing atomized supplemental fuel into the exhaust conduit upstream of the trap and a supply of supplemental fuel and compressed air is provided. A microprocessor-based control unit is adapted to operate the bypass blower under a condition of reduced bypass during normal operation of the engine. However, when backpressure in an exhaust conduit rises to a predetermined level due to particulate build-up, the bypass blower setting is changed to increase the amount of bypass of scavenging air in order to reduce the trapped air/fuel ratio and raise the temperature of the exhaust materials. Compressed air and supplemental fuel are then delivered to the nozzle to promote burning of the exhaust materials and regeneration of the respective trap.

Abstract: A particle display comprises a plurality of particles which in an electrical field rotate to expose either their white or black surface depending upon the polarity of the field. The particle display can be used for a flat panel ambient-illuminated numeric, alpha-numeric and other forms of visual displays.

Abstract: An orthodontic bracket of the type intended for cementing directly to a previously etched surface of the tooth enamel has on the lingual face thereof that contacts the tooth enamel surface a thin porous layer of sintered metal powder which is arranged to have a porosity such that it has keying characteristics close to that of the etched enamel and thereby facilitates the cementing adhesion of the bracket to the tooth. A particularly suitable metal powder consists of particles of the same alloy as the bracket metal and of size in the range about 10 to about 150 micons (-100 mesh), preferably from about 10 to about 50 microns (-300 mesh) applied in a thickness of about 0.05 to 0.2 mm, by means of a sintering operation that fuses the particles to the lingual face and to one another.

Abstract: A liquid purification system using buoyant filter media for removing suspended solids from liquid comprising a vessel having a wastewater inlet and a clarified effluent outlet. Baffles are provided in the vessel to define an upflow region for the wastewaters over a weir into a downflow region for subsequent removal by the effluent outlet. Buoyant media is provided in the upflow and downflow regions where the buoyancy of the media in the upflow region carries some of the buoyant media over into the downflow region until equilibrium is reached. A device may be provided for the continuous removal, washing and return of buoyant media to the system.

Abstract: An implement handle is made for use by a crippled person, utilizing a cap adapted to receive an end of the implement and an initially flexible bag attached to the cap. Material in the plastic state is inserted into the bag, the material becoming rigid with the passage of time, and the bag is placed into the hand of the crippled person while the material is becoming rigid. The crippled person maintain a substantially constant grip on the bag during this process, whereupon the rigidified handle conforms itself to his particular grip.

Abstract: Process and apparatus for the recovery of low concentrations of volatile components from a liquid by use of a stripping gas is disclosed. The system is particularly suited for recovery of low concentration volatile metabolites from fermentation broths.

Abstract: A particulate trap system used with a diesel engine has an exhaust conduit ducting exhaust materials through an exhaust cooler, then through a particulate trap, and then to the atmosphere. A by-pass conduit is connected in parallel with the exhaust cooler, and valves are located in the exhaust conduit and the by-pass conduit. A microprocessor-based control unit is arranged to allow normal operation with the exhaust materials passing through the cooler. However, when backpressure in the exhaust conduit reaches a predetermined level due to particulate build-up in the trap, the valves are gradually reversed, so that non-cooled exhaust materials arrive at the trap, thus regenerating it due to combustion.

Abstract: A particulate trap system for use with a diesel engine includes a first particulate trap in heat exchange relation with the exhaust materials passing through the first exhaust bank, and a second particulate trap similarly located with respect to the second exhaust bank. A first exhaust pipe extends from the first exhaust bank to the inlet of the second trap, while a second exhaust pipe extends from the second exhaust bank to the inlet of the first trap. Each exhaust pipe is sufficiently long to allow some condensation of hydrocarbons in the exhaust materials due to cooling thereof. When the mixture of exhaust gases and condensed hydrocarbons arrives in the respective traps, the temperature is again increased due to the heat exchange taking place, and trap regeneration through combustion takes place.

Abstract: A method and apparatus are provided for measuring the viscosity of a fluid medium such as drilling mud. A rotary member is mounted within a housing for free rotation and viscous drag means applies a torque-induced rotation to the rotary member. The rotary member has a portion moving adjacent to a fixed surface but out of contact with the fixed surface, thus defining a fluid cavity in which the fluid medium to be tested can be placed, in order to be sheared by relative movement between the portion and the fixed surface. Means are provided to measure the rotational speed of the rotary member, whereby the geometry of the fluid cavity and the nature of the viscous drag means can be used in a determination of the viscosity of the fluid medium to be tested.

Abstract: A density meter includes a main body having a vertically elongated chamber to contain a test fluid. A passageway in the main body connects to the chamber near its bottom end. The passageway spans at least a bottom portion of the chamber and leads to the exterior of the main body. The chamber has in its lower end a liquid which is immiscible with and denser than the test fluid, the liquid also occupying at least part of the passageway. Access means are provided for admitting the test fluid to the chamber and evacuating it therefrom. Measuring means are provided for determining the location of the top surface of the liquid. The measuring means to determine the location of the liquid top is preferably ultrasonic.

Abstract: An apparatus includes a main housing with a permeable cylindrical sleeve in the main housing to simulate a rock formation through which a well is drilled. A compartment is defined outside the sleeve and a solids-containing fluid is introduced into the interior of the sleeve and pressurized, so that the fluid passes through the sleeve and into the compartment, leaving a filter cake on the inside of the sleeve. A probe extends through the sleeve to simulate a drill string, and the probe can be moved toward and away from the inside surface of the sleeve. The apparatus includes a means for determining the filter cake thickness, preferably ultrasonically.

Abstract: A bore hold hydraulics simulator for drilling fluid is disclosed, in which the drilling fluid is flowed along a permeable partition which divides a first volume containing the drilling fluid from a second volume adapted to collect filtrate passing through the permeable partition. A pressure differential is established across the partition so as to promote the passage of filtrate into the second volume, and a vessel is provided for collecting the filtrate passing into the second volume.

Abstract: The extent of recovery of precious metals, preferably gold and silver, from precious metal ores, concentrates, tailings and wastes which are also sulphide- and arsenic- and/or antimony-bearing, is enhanced by treatment with Caro's acid (H.sub.2 SO.sub.5).

Abstract: Titanium and iron values are recovered from ores, concentrates and slags by effecting solid-state reduction and carburization to form titanium carbide and carburized iron, separation of the carburized iron, and low temperature chlorination of the titanium carbide to gaseous substantially pure titanium tetrachloride, which may be oxidized to pigmentary titanium dioxide.

Abstract: Porous polymeric material, which, in tubular form, is suitable for use as a vascular graft, is made by a procedure wherein polymeric fibres are wound on a mandrel while overlying fibres are simultaneously bonded together. In one preferred embodiment, a viscous solution of a biocompatible polymer is extruded from a spinnaret to form a plurality of filaments which are wound on a rotating mandrel as the spinnaret reciprocates relative to the mandrel. The filaments are wet as they contact each other, so that on evaporation of the solvent the fibres become bonded to each other.

Abstract: Asbestos fibres having excellent properties in resin reinforcement are produced by controlled heat treatment of a coarse fraction of chrysotile asbestos fibres.

Abstract: Metals in oxide, carbonate and/or hydroxide form in ores or ore concentrates are converted to the corresponding carbide by a solid state reaction with carbon. The carbide then is separated in substantially pure form from the gangue constituents and may be converted to the metal.

Abstract: There is provided a metacarpal-phalangeal joint replacement having two members, one for insertion into each of the respective bones in the joint. Each member defines a tail and a head, and the two heads are adapted to fit with each other in such a way that when the finger is extended, the joint and thus the finger have a limited degree of lateral freedom to swing from side to side, whereas when the finger is flexed, this lateral freedom is considerably restricted. This variation is brought about by making the face of one head generally protuberant, and the face of the other head generally recessed or channeled. The "match" in contour between the two faces thus varies during the pivoting of the one member with respect to the other, between a substantially complementary fit when the finger is flexed, to a "loose" or "wobble" fit when the finger is extended.

Abstract: A surgical prosthetic device or implant is disclosed consisting of a coherent metal substrate and a pure metal porous coating. The pure metal porous coating is formed by thermal decomposition of a coating of thermally-decomposable metal compound particles and sintering of the metal particles so formed. The surface of the device or implant is irregular but the porosity is substantially uniformly distributed throughout the coating. The coating is strongly adherent to the substrate and supports the ingrowth of bone tissue for fixation of the device or implant in the body. Such coating also supports the ingrowth of fibrous tissue for the attachment of tendons and ligaments to the device.

Abstract: Asbestos fibres having excellent properties in resin reinforcement are produced by controlled heat treatment of a coarse fraction of chrysotile asbestos fibres.