Patents by Inventor John Pickett Dismukes
John Pickett Dismukes has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 6624228Abstract: The present invention provides for microporous ceramic materials having a surface area in excess of 50 m2/gm and an open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.015 cm3/gm of the ceramic. The invention also provides for a preceramic composite intermediate composition comprising a mixture of a ceramic precursor and finely divided particles comprising a non-silicon containing ceramic, carbon, or an inorganic compound having a decomposition temperature in excess of 400° C., whose pyrolysis product in inert atmosphere or in an ammonia atmosphere at temperatures of up to less than about 1100° C. gives rise to the microporous ceramics of the invention. Also provided is a process for the preparation of the microporous ceramics of the invention involving pyrolysis of the ceramic intermediate under controlled conditions of heating up to temperatures of less than 1100° C.Type: GrantFiled: June 21, 1996Date of Patent: September 23, 2003Assignee: ExxonMobil Research and Engineering CompanyInventors: John Pickett Dismukes, Jack Wayne Johnson, Edward William Corcoran, Jr., Joseph Vallone
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Patent number: 5902759Abstract: The present invention provides for microporous ceramic materials having a surface area in excess of 70 m.sup.2 /gm and an open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.03 cm.sup.3 /gm of the ceramic. The invention also provides for a preceramic composite intermediate composition comprising a mixture of a ceramic precursor and finely divided silicon carbide or silicon nitride, whose pyrolysis product in inert atmosphere or in an ammonia atmosphere at temperatures of up to less than about 1100.degree. C. gives rise to the microporous ceramics of the invention. Also provided is a process for the preparation of the microporous ceramics of the invention involving pyrolysis of the ceramic intermediate under controlled conditions of heating up to temperatures of less than 1100.degree. C. to form a microporous ceramic product.Type: GrantFiled: January 21, 1997Date of Patent: May 11, 1999Assignee: Exxon Research and Engineering Co.Inventors: John Pickett Dismukes, Jack Wayne Johnson, Edward William Corcoran, Jr., Joseph Vallone, James J. Pizzulli, Jr., Michael P. Anderson
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Patent number: 5872070Abstract: The present invention provides for amorphous, nanoporous, ceramic material having a surface area in excess of 70 m.sup.2 /gm and characterized by a high content of open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.03 cm.sup.3 /gm of the ceramic. The invention also provides a process for the preparation of such nanoporous ceramics wherein a ceramic precursor polymer or oligomer is gradually heated in the presence of an inert gas or vacuum up to a maximum temperature in the range of greater than 400.degree. C. up to about 650.degree. C. Optionally, the process may also include a crosslinking step conducted prior to the heating step wherein the precursor polymer or oligomer is heated in the presence of a crosslinking agent capable of undergoing addition or substitution reactions with backbone atoms present in said precursor material, at an intermediate temperature of about 100.Type: GrantFiled: January 3, 1997Date of Patent: February 16, 1999Assignee: Exxon Research and Engineering CompanyInventors: John Pickett Dismukes, Jack Wayne Johnson, James L. Pizzulli
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Patent number: 5696217Abstract: The present invention provides for microporous ceramic materials having a surface area in excess of 100 m.sup.2 /gm and an open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.05 cm.sup.3 /gm of the ceramic. The pyrolysis product of ceramic precursor oligomers or polymers having a number average molecular weight in the range of from about 200 to about 100,000 g/mole in an ammonia atmosphere at temperatures of up to less than about 1200.degree. C. gives rise to the microporous ceramics of the invention. Also provided is a process for the preparation of the microporous ceramics of the invention involving pyrolysis of the ceramic precursor under controlled conditions of heating and with intermediate hold times, up to temperatures of less than 1200.degree. C., preferably less than 1000.degree. C., to form a microporous ceramic product.Type: GrantFiled: February 10, 1995Date of Patent: December 9, 1997Assignee: Exxon Research & Engineering CompanyInventors: John Pickett Dismukes, John Stewart Bradley, Jack Wayne Johnson, Edward William Corcoran, Jr.
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Patent number: 5643987Abstract: The present invention provides for microporous ceramic materials having a surface area in excess of 70 m.sup.2 /gm and an open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.03 cm.sup.3 /gm of the ceramic. The invention also provides for a preceramic composite intermediate composition comprising a mixture of a ceramic precursor and finely divided silicon carbide or silicon nitride, whose pyrolysis product in inert atmosphere or in an ammonia atmosphere at temperatures of up to less than about 1100.degree. C. gives rise to the microporous ceramics of the invention. Also provided is a process for the preparation of the microporous ceramics of the invention involving pyrolysis of the ceramic intermediate under controlled conditions of heating up to temperatures of less than 1100.degree. C. to form a microporous ceramic product.Type: GrantFiled: May 24, 1994Date of Patent: July 1, 1997Assignee: Exxon Research and Engineering CompanyInventors: John Pickett Dismukes, Jack Wayne Johnson, Edward William Corcoran, Jr., Joseph Vallone, James J. Pizzulli, Jr., Michael P. Anderson
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Patent number: 3981819Abstract: A family of luminescent materials or phosphors having a rhombohedral crystal structure and consisting essentially of a mixed host sulfide of at least one monovalent host cation and at least one trivalent host cation, and containing, for each mole of phosphor, 0.0005 to 0.05 mole of at least one activating cation. The monovalent host cations may be Na, K or Rb and Cs. The trivalent host cations may be Gd, La, Lu, Sc and Y. The activating cations may be one or more of trivalent As, Bi, Ce, Dy, Er, Pr, Sb, Sm, Tb and Tm; divalent Eu, Mn, Pb and Sn; and monovalent Ag, Cu, and Tl. The novel phosphors may be used in devices to convert electron-beam, ultraviolet or x-ray energy to light in the visible spectrum. Such energy conversion can be employed for example in fluoroscopic screens, and in viewing screens of cathode-ray tubes and other electron tubes.Type: GrantFiled: December 23, 1974Date of Patent: September 21, 1976Assignee: RCA CorporationInventors: Perry Niel Yocom, John Pickett Dismukes