Abstract: A plasticizing unit is provided for palsticizing material which is subsequently supplied to an injection molding press. The unit includes a screw disposed in a barrel which has an inlet, an outlet, a reservoir zone portion, and a plasticizing zone portion. The plasticizing zone portion of the barrel and the screw each have a continuous helical groove of opposite hand as the other groove and the grooves transfer material therebetween to effect plasticizing of the material. The reservoir zone portion of the barrel receives a shot volume of material which has been plasticized during passage through the helical grooves of the barrel and the screw. A volume displacement member which is axially movably disposed in a bore of the screw is movable within the reservoir zone portion to selectively control the shot volume of plasticized material received in the reservoir zone portion.

Abstract: A Transfermix cold feed extruder having a plasticizing section that includes a plurality of screw flights therein in a transfer zone that is formed over a common length of the screw and barrel of the extruder. In the transfer zone, a helical groove in the screw varies in cross section from a full area to a zero area, and a helical groove of opposite hand in the barrel correspondingly varies in cross section from a zero area to a full area. The extruder is provided with a set of flow deflectors in a cut in the screw positioned immediately upstream of the plasticizing section. By the coaction of the flow deflectors with the plurality of screw flights, an increase of throughput for difficult-to-extrude compounds, with an improvement in the quality of the extrudate, is obtained in a surprising manner.

Abstract: A controlled release and delivery system for a hydrophobic, water sensitive herbicide is produced by:(a) dissolving the herbicide in a volatile water-immiscible solvent;(b) introducing the solvent containing the herbicide dissolved therein to a latex dispersion comprising an aqueous continuous phase and polymeric discrete phase;(c) agitating the resultant mixture until the polymeric particles of the discrete phase absorb the herbicide; and(d) removing the solvent from the resultant mixture at reduced pressure.

Abstract: A single-rotor cold feed extruder having a barrel and a screw and incorporating a transfermix plasticizing/mixing section is disclosed. The extruder is provided with a fixed set of flow-interrupters/deflectors carried by the barrel and positioned in a circumferential cut in the screw downstream of the transfermix section. The extruder is characterized by radially movable throttle members which are located around the flow interrupters/deflectors so as to provide an increase of throughput for and improved quality of difficult-to-extrude compounds.

Abstract: A binding rubber extruder for retreading tires is provided with an extruder head, an axis of which extends essentially vertically to a surface of a carcass. The revolving speed of the rotatably drivable carcass and the extrusion speed are adjusted relative to one another. The extruder head is provided with a nozzle, that has a radius of curvature that corresponds at least to a greatest radius of the carcass whereby the nozzle is pressable against the carcass surface with a gentle, elastic force.

Abstract: A controlled release and delivery system for a hydrophobic, water sensitive herbicide is produced by:(a) dissolving the herbicide in a volatile water-immiscible solvent;(b) introducing the solvent containing the herbicide dissolved therein to a latex dispersion comprising an aqueous continuous phase and polymeric discrete phase;(c) agitating the resultant mixture until the polymeric particles of the discrete phase absorb the herbicide; and(d) removing the solvent from the resultant mixture at reduced pressure.

Abstract: A process for the prosthetic supplementation or replacement of hard tissue. In the process an anatomically-shaped form is molded by or a prosthetic device is coated with a composite material containing unsintered calcium phosphate biomaterial, a synthetic biodegradable polymer, and optionally, a pore-forming agent.

Abstract: A tractor includes: (a) a one piece frame having opposite ends defined by respective members adapted for receiving ballast with the rear member including a hitch located below any mounted ballast, (b) a dual screen filtering arrangement located upstream of a radiator and an engine combustion air inlet, (c) an implement lift system including a main spring lift assist which is locked out when the implement is lowered and an auxiliary lift assist for increasing the lift assist for front-mounted implements but is mounted so as to join the main lifts assist to produce a near constant lift force during lifting the implement while producing a minimal lift force when the implement is completely lowered (d) short and long effective lengths of a steering pitman arm may be selected, for respectively minimizing steering effort or maximizing responsiveness, by respectively connecting a mounting point closest to or a mounting point farthest from a pivot axis of the arm to a drag link, (e) a steering wheel is tiltable toget

Abstract: The increasingly high standards of consistency and uniformity demanded of cold feed rubber extruders are met by providing notches in the flights of the screw at least in the feed-inlet of the extruder. The notches are at a lead-angle greater than that of the extruder screw flights, so to pull the rubber and advance it positively. Throttling means are used to adjust the amount of squash-back and there is an independently variable-speed drive for a feed roller in the feed inlet.

Abstract: A process for the prosthetic supplementation or replacement of hard tissue. In the process an anatomically-shaped form is molded by or a prosthetic device is coated with a composite material containing unsintered calcium phosphate biomaterial, a synthetic biodegradable polymer, and optionally, a pore-forming agent.

Abstract: A storage stable, water emulsifiable, substantially non-aqueous liquid or low melting solid concentrate adapted for on-site preparation of an aqueous emulsion of an agricultural chemical, consisting essentially of a solution, in(a) a liquid hydrophobic agricultural chemical having biocidal activity, of(b) a solid hydrophobic polymer, in an amount effective to achieve sustained release of (a), and(c) an emulsifying agent, in an amount effective to form a stable oil-in-water emulsion when the concentrate is mixed with water.

Abstract: A tractor-implement combination comprising a tractor frame supported on front and rear wheels and having left and right side plate means has a horizontal tube structure extending through the side plate means to oppositely, transversely spaced open ends. A transverse beam is slidably mounted within the tube and has opposite end portions projecting transversely outwardly of the open ends of the tube. A pair of implement supports detachably secured to said end portions and an implement is carried on the implement supports.

Abstract: A storage stable, water emulsifiable, substantially non-aqueous, liquid concentrate adapted for on-site preparation of an aqueous emulsion of an agricultural chemical, consisting essentially of a solution of(a) a hydrophobic agricultural chemical having biocidal activity,(b) a solid hydrophobic polymer, in an amount effective to achieve sustained release of (a),(c) a water immiscible organic solvent, and(d) an emulsifying agent, in an amount effective to form a stable oil-in-water emulsion when the concentrate is mixed with water.

Abstract: A tractor-implement combination comprising a tractor frame supported on front and rear wheels and having left and right side plate means has a horizontal tube structure extending through the side plate means to oppositely, transversely spaced open ends. A transverse beam is slidably mounted within the tube and has opposite end portions projecting transversely outwardly of the open ends of the tube. A pair of implement supports detachably secured to said end portions and an implement is carried on the implement supports.

Abstract: Composite materials useful as hard tissue prosthetics comprising synthetic biodegradable polymers and unsintered calcium phosphate biomaterials optionally porositized by pore-forming agents are described. The composite materials may be ground and blended with a compatible water soluble pore-forming agent and then molded to form dense, shaped objects which may be made porous by leaching out said water soluble pore-forming agent. The composites may be used as hard tissue prosthetics either alone or in conjunction with conventional prostheses.

Abstract: An in situ polymerization process is disclosed whereby an .alpha.-amino acid N-carboxyanhydride is blended intimately and efficiently with one or more calcium phosphate biomaterials. The polymerization proceeds at ambient temperature and pressure without the need for initiators or surface modification of the calcium phosphate biomaterials. The resulting composite material may subsequently be ground and blended with a compatible water soluble pore-forming agent and then molded to form dense, shaped objects which may be made porous by leaching out said water soluble pore-forming agent. The resulting shaped objects may then be used as hard tissue prosthetics either alone or in conjunction with conventional prostheses.

Abstract: Composite materials useful as hard tissue prosthetics comprising synthetic biodegradable polymers and unsintered calcium phosphate biomaterials optionally porositized by pore-forming agents are described. The composite materials may be ground and blended with a compatible water soluble pore-forming agent and then molded to form dense, shaped objects which may be made porous by leaching out said water soluble pore-forming agent. The composites may be used as hard tissue prosthetics either alone or in conjunction with conventional prostheses.

Abstract: An in situ polymerization process is disclosed whereby an .alpha.-amino acid N-carboxyanhydride is blended intimately and efficiently with one or more calcium phosphate biomaterials. The polymerization proceeds at ambient temperature and pressure without the need for initiators or surface modification of the calcium phosphate biomaterials. The resulting composite material may subsequently be ground and blended with a compatible water soluble pore-forming agent and then molded to form dense, shaped objects which may be made porous be leaching out said water soluble pore-forming agent. The resulting shaped objects may then be used as hard tissue prosthetics either alone or in conjunction with conventional prostheses.

Abstract: The present invention is directed to mineral filled .alpha.-amino acid polymer composite materials. The composite materials are prepared by the in situ polymerization of an .alpha.-amino acid N-carboxyanhydride in the presence of mineral fillers which are optionally surface-modified with a partially hydrolyzed polyoxazoline prior to said polymerization. Composite materials prepared in this manner consist of an intimate mixture of polymer and mineral filler which may be optionally blended with a crosslinking agent and then molded to produce smooth, hard homogeneous materials that are water and oil resistant and have good heat distortion properties.

Abstract: An extrusion apparatus having a barrel and a rotatable threaded screw coaxially positioned therein is disclosed. The apparatus includes an upstream inlet section having an opening therein for receiving material to be processed by the apparatus, a compression section downstream of the inlet section, and a mixing or plasticizing section downstream of the compression section. The interior surface of the barrel is provided with an undercut therein which intercommunicates the feed opening with the compression section and has a portion thereof which extends downstream in the compression section about the interior surface of the barrel with a continuously decreasing cross-sectional area. The undercut may be formed in a cylindrical insert carried within the barrel and, in an alternate embodiment, a second undercut cylindrical insert positioned about the first insert and rotatable relative thereto may be employed to vary the cross-sectional area of the undercut.