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Ceramic materials with low thermal conductivity and low coefficients of thermal expansion
(United States Patent and Trademark Office, 1992-04-07)
Compositions having the general formula (Ca.sub.x Mg.sub.1-x)Zr.sub.4 (PO.sub.4).sub.6 where x is between 0.5 and 0.99 are produced by solid state and sol-gel processes. In a preferred embodiment, when x is between 0.5 and ...
Mixing process for generating in-situ reinforced thermoplastics
(United States Patent and Trademark Office, 1993-07-06)
A method for blending polymeric materials includes the steps of producing a melt stream of a first polymer from a first extruder (12) and a separate melt stream of a second polymer from a second extruder (14), joining the ...
Zero-voltage-transition (ZVT) 3-phase PWM voltage link converters
(United States Patent and Trademark Office, 1996-11-12)
An improved zero voltage transition (ZVT) pulse width modulation (PWM) link converter is provided which introduces a space vector modulation scheme and an auxiliary circuit which includes a commutation power supply or ...
Method of producing prepolymers from hydroxyalkyl lignin derivatives
(United States Patent and Trademark Office, 1992-04-07)
A method of producing prepolymeric materials from lignin is disclosed. The method uses lignin which has been hydroxyalkyl modified, such that the lignin is substantially non-phenolic and solvent soluble and/or liquid. The ...
Reduced operator emission exposure antennas for safer hand-held radios and cellular telephones
(United States Patent and Trademark Office, 1996-07-30)
An antenna for a personal communication device designed for reducing RF emissions to a user's head and body comprises a single half-wave dipole antenna element mounted on the top of a telescoping rod such that the antenna ...
Compositions for forming high temperature ceramic particulate filters
(United States Patent and Trademark Office, 1993-10-12)
A high temperature ceramic filter is produced from a composition containing refractory cement, aggregate, pore forming additives, and sintering agents. The pore forming additives are synthetic or organic powders or fibers ...
Video instrumentation for the analysis of mineral content in ores and coal
(United States Patent and Trademark Office, 1995-03-07)
Mineral content in processed ore and coal content in coal slurries are determined using a video system. A video image is taken of a sample, the video image is digitized, and gray levels are assigned to points or areas on ...
Soft-switching PWM converters
(United States Patent and Trademark Office, 1995-08-15)
A full-bridge zero-voltage-switching pulse-width-modulated converter employs a saturable reactor in place of the linear inductor in order to reduce current stress on the active switches, reduce voltage stress on the rectifier ...
Soft switched three-phase boost rectifiers and voltage source inverters
(United States Patent and Trademark Office, 1997-05-27)
A boost rectifier is provided with an ultra high speed diode in its direct current rail to reduce diode reverse recovery loss with or without implementing a soft switching technique. Full zero-voltage-transition (ZVT) as ...
Method of producing star-like polymers from lignin
(United States Patent and Trademark Office, 1991-11-19)
A method of producing prepolymeric materials from lignin is disclosed. The method uses lignin which has been hydroxyalkyl modified, such that the lignin is substantially non-phenolic and solvent soluble and/or liquid. The ...