Abstract: This disclosure relates to shape memory alloys which have been subjected to a thermal and mechanical treatment to increase the austenite start temperature As?As? such that the shape memory alloy is martensitic at body temperature and when subsequently subjected to a controlled deformation, the shape memory alloy preferentially reverts to the parent phase. One application for this disclosure is a stent for use in a lumen in a human or animal body having a generally tubular body formed from a shape memory alloy which has been subjected to a thermal and mechanical treatment so it deforms as martensite until a critical expansion diameter is reached at which point the tubular body rapidly reverts to the parent phase with much higher mechanical properties. The shape memory alloy comprises Ni—Ti and a ternary element ranging from about 3 at. % to about 20 at. %. The ternary element is effectively insoluble in a Ni—Ti matrix.

Abstract: This disclosure relates to shape memory alloys which have been subjected to a thermal and mechanical treatment to increase the austenite start temperature As?As? such that the shape memory alloy is martensitic at body temperature and when subsequently subjected to a controlled deformation, the shape memory alloy preferentially reverts to the parent phase. One application for this disclosure is a stent for use in a lumen in a human or animal body having a generally tubular body formed from a shape memory alloy which has been subjected to a thermal and mechanical treatment so it deforms as martensite until a critical expansion diameter is reached at which point the tubular body rapidly reverts to the parent phase with much higher mechanical properties. The shape memory alloy comprises Ni—Ti and a ternary element ranging from about 3 at. % to about 20 at. %. The ternary element is effectively insoluble in a Ni—Ti matrix.

Abstract: This invention relates to medical devices comprising shape memory alloys which have been subjected to a thermal and mechanical treatment to increase the austenite start temperature As to As? such that the shape memory alloy is martensitic at body temperature and when subsequently subjected to a controlled deformation, the shape memory alloy preferentially reverts to the parent phase. The shape memory alloy comprises nickel, titanium and a ternary element, preferably 3 at. % to about 20 at. %. The ternary element is insoluble in a Ni—Ti matrix. In a preferred embodiment, the element is selected from the group consisting of niobium, tantalum and zirconium.

Abstract: This disclosure relates to shape memory alloys which have been subjected to a thermal and mechanical treatment to increase the austenite start temperature As?As? such that the shape memory alloy is martensitic at body temperature and when subsequently subjected to a controlled deformation, the shape memory alloy preferentially reverts to the parent phase. One application for this disclosure is a stent for use in a lumen in a human or animal body having a generally tubular body formed from a shape memory alloy which has been subjected to a thermal and mechanical treatment so it deforms as martensite until a critical expansion diameter is reached at which point the tubular body rapidly reverts to the parent phase with much higher mechanical properties. The shape memory alloy comprises Ni—Ti and a ternary element ranging from about 3 at. % to about 20 at. %. The ternary element is effectively insoluble in a Ni—Ti matrix.

Abstract: The invention provides a helical antenna to broadcast a signal from an input line. The antenna includes a base plate and a dielectric rod mounted on the base plate. A conductive helix, surrounds the dielectric rod, and the rod has a pitch angle of at least 12 degrees. A matching network is connected to the conductive helix, to match an impedance of the conductive helix with an impedance of the signal.

Abstract: A parallel fed colinear dipole array antenna for broadcasting and receiving a signal of a selected wavelength. The antenna comprises a plurality of elongate dipole antennas attached end-to-end in a linear array. A power divider divides and transmits a signal in parallel to each of the dipole antennas. The linear spacing of the dipoles is correlated with the dimensions of the dipoles and the selected wavelength, such that the signals of the dipole antennas interfere with each other when broadcast, so as to focus signals which propagate substantially perpendicularly to the linear array, and to diminish other signals.

Abstract: The invention provides a helical antenna to broadcast a signal from an input line. The antenna includes a base plate and a dielectric rod mounted on the base plate. A conductive helix, surrounds the dielectric rod, and the rod has a pitch angle of at least 12 degrees. A matching network is connected to the conductive helix, to match an impedance of the conductive helix with an impedance of the signal.

Abstract: The invention comprises an apparatus, a method and a system for recovering and purifying a refrigerant contained in a refrigerator, an air conditioning system, a storage tank, or other source. The refrigerant is flowed sequentially through a purifying device, an expansion valve for controlling the flow of the refrigerant, one or two heat exchangers wherein heat is exchanged to convert the refrigerant into a gaseous phase, a second purifying device for separating oil from the refrigerant, a compressor-pump, a third purifying device for filtering moisture, acids, and particulates, and a moisture indicator monitors the amount of moisture present in the recovered refrigerant. The refrigerant then may be flowed into a receiving tank, and thence dispensed therefrom back into the refrigerant source, a storage tank, or recirculated again through the apparatus. The apparatus also comprises means for leak testing the refrigerant source, and for pressure-clearing obstacles from the refrigerant source.

Abstract: In liquid ring gas pumps of the type having a rotor rotatably mounted in a stationary housing for forming a quantity of pumping liquid into a recirculating ring inside the housing, fluid friction loss between the liquid and the housing is reduced by shaping the surface of the housing which is in contact with the liquid ring radially outside the rotor so as to minimize or at least substantially reduce the area of that surface.