A die pair for use in high temperature high pressure apparatus for use in the synthesis of super hard materials such as diamonds, cubic boron nitride or the like in which the dies include an annular step structure on confronting cooperating faces of the dies to afford over an extended period of time stable, repetitive temperatures in the order of thousands of degrees centigrade and pressures in the order of 60 thousand atmospheres; the confronting die faces having recesses forming a pressure cha...

A high-voltage, high-current coaxial connector utilized with a coaxially coupled parallel capacitor bank coupled through an electronic switch.

An admixture of (1) from 55 to 70 percent by weight of hydrated alumina and (2) from 30 to 45 percent by weight of a petroleum oil extended ethylene-propylene-diene terpolymer, containing from 20 to 100 phr. of oil, is molded about electrical apparatus to provide insulation for components thereof. The hydrated alumina is advantageously finely divided so that a major portion or substantially all particles are less than 2 microns. The terpolymer is derived from the reaction of an admixture of (I) ...

The drive coupling for an antenna having a shorting assembly traveling along a helix to tune the antenna includes a metal rotating drive shaft extending concentrically through the shorting assembly with flutes on the drive shaft in the region of the helix. A metal shielding cylinder is disposed coaxial to and spaced from the outer surface of the drive shaft and provides an outer member of the shorting assembly. A drive bearing of dielectric material is disposed to engage the flutes and the shiel...

A plasma thyristor circuit is provided for generating high power, ultra-short duration electrical signals. A silicon semiconductor body has first, second and third impurity regions therein with a PN junction formed at the transition between the first and second or the second and third impurity regions. The second impurity region has an impurity concentration of less than about 5 .times. 10.sup.14 atoms/cm.sup.3, and a width of greater than about 80 microns. The ratio of the punch-through voltage...

In a device for treating material at high temperature and high pressure which includes a high pressure cylinder built from a tube and a prestressed, force-absorbing wire or strip sheath wound around the tube, with end closures projecting into the cylinder and a press stand for holding the end closures, the cylinder is provided with longitudinally extending cooling channels either running along the inner wall of the sheath or at an intermediate position within the sheath, adjacent to the inner wa...

In the proposed apparatus, each plunger shaped as a truncated pyramid is provided with grooves extending along the edges of the smaller base of the pyramid and forming circular passages round a working chamber in the gaps between adjacent plungers. The cross section of each passsge is defined by smooth curves, the passages being filled with a sealing material. In each gap between plungers, there may be provided a plurality of parallel passages which, in some cases, are filled with materials of d...

A high speed steel having high wear-resistance having a ferrous matrix consisting essentially of iron and containing 0.2-0.6 wt.% combined carbon, in which said matrix has crystallized therein a carbide which is formed by the combination of 5-12 wt. % of vanadium and 3-10 wt. % of niobium with an amount of carbon just enough for combination therewith.

A high speed steel having high wear resistance consisting essentially of 3.1 to 6.3% by weight of carbon, 5 to 12% by weight of vanadium, 3 to 10% by weight of niobium, and the balance substantially iron, wherein all of vanadium and niobium reacts with carbon, 1.4 to 3.6% by weight of carbon forms cementite and 0.1 to 0.6% by weight of carbon dissolves in a ferrous matrix as hardened.

A lightweight vehicle giving very high performances but affording a considerable degree of security for young athletic customers. It includes an aerodynamic cockpit protected by the spare-wheel and two lateral shields. Both occupants take places on two seats disposed tandem-fashion. An horizontal stabilizer extending on either side of the rear point of the cockpit ensures a perfect stability while an aerodynamic brake disposed at the upper part of said horizontal stabilizer affords a great secur...