Abstract: An oligo- or polyimide comprising one or two residue(s) of an anhydride based acetylenic end-capper, at least one EBPA residue, at least one residue of anaromatic di-amine, and optionally at least one residue of an aromatic non-acetylenic di-anhydride is disclosed. A method for obtaining such an oligo- or polyimide is also disclosed.

Abstract: A system receives an emergency call, a local exchange carrier (LEC) charge number, and Calling Party Number (CPN) from a user device, and overrides the LEC charge number with the CPN for Automatic Number Identification (ANI) determination purposes. The system also determines the ANI of the user device based on the CPN, receives an address associated with the user device based on the ANI, and provides the emergency call and the address to a Public Safety Answering Point (PSAP).

Abstract: The disclosed compositions and methods for producing composite materials that are suitably adapted for use in elevated temperature environments generally include the use of oxyarylbisorthodinitrile matrix resins in conjunction with aromatic amines to produce an improved phthalonitrile-based composite. Various features and specifications may be controlled, adapted or otherwise optionally modified to improve the temperature-rated performance of the disclosed composite materials. Exemplary embodiments of the present invention generally provide composite materials that offer improved strength at temperatures in excess of 600° F.

Abstract: A system for modified resin and composite material and methods therefor generally comprise a plurality of clay nanoparticles dispersed in a high temperature resin to provide enhanced microcrack resistance and maintenance and/or improvement of thermal and mechanical properties. In one embodiment, the invention further comprises a reinforcement disposed in the modified resin, wherein the reinforcement and modified resin together comprise a composite material.

Abstract: A method for data exchange with a mobile asset wherein the communication link quality at the location of the mobile asset is measured at the time of the data transfer. The packet size for the data transfer is selected in response to the communication link quality. The current communication link quality measurement may be used alone or in combination with historical communication link quality data for selecting the data packet size. Communication link quality may be determined repeatedly and the packet size reset accordingly in response to changes in the link quality. A difference between the current communication link quality and historical link quality data may trigger appropriate corrective action, such as identifying the source of intentional or unintentional jamming.

Abstract: A method for data exchange with a mobile asset including the step of comparing the quality of the communication link to a predetermined value prior to initiating the communication. Polling of a fleet of mobile assets may be scheduled by considering a map of the communication link quality along the route of the mobile assets. An optimal packet size may be selected for the data transfer by considering the quality of the communication link.

Abstract: The present invention is directed to polyimide systems which simultaneously offer low toxicity, a high glass transition temperature, excellent thermal oxidative stability, and desirable processing characteristics. These various polyimide systems include mixtures of monomeric reactants, polyimide-precursor reaction products, polyimides, and polyimide-containing articles. In one aspect of the invention, the mixture of monomeric reactants includes at least one dia-nhydride or a derivative thereof, and at least one diamine. The diamine may be 4,4′-[1,4-phenylene-bis(1-methylethylidene)]bisaniline, 4,4′-[1,3-phenylene-bis(1-methylethylidene)]bisaniline, and/or a derivative thereof. The diamine also may include a phenylenediamine, 2,2-bis[4-(4-aminophenoxyl)phenyl]propane, 4,4′(1,4-phenylene-bismethylene)bisaniline, and/or a derivative thereof. In addition, the mixture may include a reactive end-capping agent and/or a non-reactive end-capping agent.

Abstract: Induction heating is utilized to heat polymer matrix composites containing electrically conductive fibers. This is accomplished with an apparatus having a mold with first and second cores positioned to receive a workpiece therebetween and first and second induction coils mounted to the first and second cores, respectively. Each induction coil is encapsulated in a layer of non-electrically conductive material which is attached to a surface of the respective core. A thermal insulation layer is attached to each layer of material, and a skin layer is attached to each thermal insulation layer. Alternatively, the induction coils can be embedded in the corresponding mold core. In another alternative, a single helical induction coil can be disposed around the two mold cores.

Abstract: A machine for producing a graphite fiber tape suitable for use in the protion of metal matrix composites by physical vapor deposition. The machine consists of adjacent air-tight enclosures. Two venturi pipes are located within the enclosures and aligned with a gap between them. A vacuum pump draws air out of one of the air-tight enclosures. Graphite fibers are drawn through the venturi pipes and laterally spread from a tow bundle via the Venturi effect to form a thin tape.

Abstract: Induction heating is utilized to heat polymer matrix composites containing electrically conductive fibers. This is accomplished with an apparatus having a mandrel for supporting a composite workpiece and a helical induction coil disposed around the mandrel. The mandrel, workpiece and induction coil are disposed in an autoclave. The mandrel is a hollow, porous member having a port formed therein which is connected to a vacuum. A vacuum bag is hermetically sealed on the mandrel so as to define an enclosure over the workpiece. A power source is connected to the induction coil and, when activated, causes the coil to generate an oscillating magnetic field lying along the longitudinal axis of the mandrel. The magnetic field induces heat-generating eddy currents in the fibers of the workpiece which are oriented orthogonally to the magnetic field.

Abstract: Polyimide intercondensation products are prepared from mixed dianhydrides and aromatic diamines. One of the mixed dianhydrides must be 2,2-bis(3,4-dicarboxyphenyl)-hexafluoropropane dianhydride (6FDA) and the other dianhydride may be oxydiphthalic anhydride (ODPA) or biphenyl dianhydride (BPDA) or mixtures thereof. Preferred aromatic diamines are p-phenylenediamine (PPD) and/or m-phenylenediamine (MPD). The polyimide products have increased glass transition temperatures (Tg), frequently higher than 400.degree. C. Composites made from the polyimides have high thermal and oxidative stability and may be used in aircraft engine hardware.

Abstract: A holder for a knife is disclosed comprising a base, a rear portion, first and second side portions, and first and second flexible portions, with the first and second flexible portions forming the front portion of the first and second side portions and pressing inward to secure the knife within the holder, with the blade of the knife held in an open area between the first and second flexible portions for easy access and utilization.