Patents by Inventor Ramakrishna Ravikiran

Ramakrishna Ravikiran 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).

  • Patent number: 10435618
    Abstract: Surfactant compositions useful for oil recovery are disclosed. The compositions comprise from 10 to 80 wt. % of a propoxylated C12-C20 alcohol sulfate, from 10 to 80 wt. % of a C12-C20 internal olefin sulfonate, and from 0.1 to 10 wt. % of an ethoxylated C4-C12 alcohol sulfate. Surprisingly, including a minor proportion of the ethoxylated alcohol sulfate reduces or eliminates the need to rely on costly cosolvents for achieving good performance in enhanced oil recovery processes. In particular, low interfacial tensions and low microemulsion viscosities can be achieved when the ethoxylated alcohol sulfate accompanies the propoxylated alcohol sulfate and internal olefin sulfonate. Aqueous concentrates comprising water and the surfactant compositions described above are also disclosed. Dilution of the surfactant composition or aqueous concentrate with water or brine to the desired anionic actives level provides an injectable composition useful for EOR applications.
    Type: Grant
    Filed: January 6, 2017
    Date of Patent: October 8, 2019
    Assignee: Stepan Company
    Inventors: Ramakrishna Ravikiran, Jieyuan Zhang
  • Publication number: 20170114270
    Abstract: Surfactant compositions useful for oil recovery are disclosed. The compositions comprise from 10 to 80 wt. % of a propoxylated C12-C20 alcohol sulfate, from 10 to 80 wt. % of a C12-C20 internal olefin sulfonate, and from 0.1 to 10 wt. % of an ethoxylated C4-C12 alcohol sulfate. Surprisingly, including a minor proportion of the ethoxylated alcohol sulfate reduces or eliminates the need to rely on costly cosolvents for achieving good performance in enhanced oil recovery processes. In particular, low interfacial tensions and low microemulsion viscosities can be achieved when the ethoxylated alcohol sulfate accompanies the propoxylated alcohol sulfate and internal olefin sulfonate. Aqueous concentrates comprising water and the surfactant compositions described above are also disclosed. Dilution of the surfactant composition or aqueous concentrate with water or brine to the desired anionic actives level provides an injectable composition useful for EOR applications.
    Type: Application
    Filed: January 6, 2017
    Publication date: April 27, 2017
    Inventors: Ramakrishna Ravikiran, Jieyuan Zhang
  • Patent number: 9567512
    Abstract: Surfactant compositions useful for oil recovery comprise from 10 to 80 wt. % of a prapoxylated C12-C20 alcohol sulfate, from 10 to 80 wt. % of a C12-C20 internal olefin sulfonate, and from 0.1 to 10 wt. % of an ethoxylated C4-C12 alcohol sulfate. A minor proportion of the ethoxylated alcohol sulfate reduces or eliminates the need to rely on costly cosolvents for achieving good performance in enhanced oil recovery processes. Low interfaoial tensions and low microemulsion viscosities can be achieved when the ethoxylated alcohol sulfate accompanies the propoxytated alcohol sulfate and internal olefin sulfonate. Aqueous concentrates comprising water and the surfactant compositions described above are also disclosed. Dilution of the surfactant composition or aqueous concentrate with water or brine to the desired anionic actives level provides an injectable composition useful for EOR applications.
    Type: Grant
    Filed: May 14, 2012
    Date of Patent: February 14, 2017
    Assignee: Stepan Company
    Inventors: Ramakrishna Ravikiran, Jieyuan Zhang
  • Publication number: 20140073541
    Abstract: Surfactant compositions useful for oil recovery comprise from 10 to 80 wt. % of a prapoxylated C12-C20 alcohol sulfate, from 10 to 80 wt. % of a C12-C20 internal olefin sulfonate, and from 0.1 to 10 wt. % of an ethoxylated C4-C12 alcohol sulfate. A minor proportion of the ethoxylated alcohol sulfate reduces or eliminates the need to rely on costly cosolvents for achieving good performance in enhanced oil recovery processes. Low interfaoial tensions and low microemulsion viscosities can be achieved when the ethoxylated alcohol sulfate accompanies the propoxytated alcohol sulfate and internal olefin sulfonate. Aqueous concentrates comprising water and the surfactant compositions described above are also disclosed. Dilution of the surfactant composition or aqueous concentrate with water or brine to the desired anionic actives level provides an injectable composition useful for EOR applications.
    Type: Application
    Filed: May 14, 2012
    Publication date: March 13, 2014
    Applicant: STEPAN COMPANY
    Inventors: Ramakrishna Ravikiran, Jieyuan Zhang
  • Patent number: 8420293
    Abstract: Embodiments in accordance with the present invention provide waveguide structures and methods of forming such structures where core and laterally adjacent cladding regions are defined. Some embodiments of the present invention provide waveguide structures where core regions are collectively surrounded by laterally adjacent cladding regions and cladding layers and methods of forming such structures.
    Type: Grant
    Filed: August 10, 2011
    Date of Patent: April 16, 2013
    Assignees: Sumitomo Bakelite Co., Ltd., Promerus, LLC
    Inventors: Koji Choki, Tetsuya Mori, Ramakrishna Ravikiran, Makoto Fujiwara, Keizo Takahama, Kei Watanabe, Hirotaka Nonaka, Yumiko Otake, Andrew Bell, Larry Rhodes, Dino Amoroso, Mutsuhiro Matsuyama
  • Patent number: 8403044
    Abstract: A process for recovering oil from an oil-bearing formation comprises introducing into said formation an aqueous composition comprising at least one sulfonated derivative of one or more internal olefins, said internal olefins being characterized by having low amounts of tri-substitution on the olefin bond, said sulfonated derivative being obtained by sulfonating a composition comprising internal olefins of the formula: R1R2C?CR3R4 wherein R1, R2, R3 and R4 are the same or different and are hydrogen or straight- or branched-chain, saturated hydrocarbyl groups and the total number of carbon atoms of R1, R2, R3 and R4 is 6 to 44 with the proviso that at least about 96 mole percent of R1 and R3 are straight- or branched-chain, saturated hydrocarbyl groups and at least about 96 mole percent of R2 and R4 are hydrogen.
    Type: Grant
    Filed: May 5, 2010
    Date of Patent: March 26, 2013
    Assignee: Stepan Company
    Inventors: John C. Hutchison, Patrick Shane Wolfe, Thomas Edward Waldman, Ramakrishna Ravikiran
  • Publication number: 20120064458
    Abstract: Embodiments in accordance with the present invention provide waveguide structures and methods of forming such structures where core and laterally adjacent cladding regions are defined. Some embodiments of the present invention provide waveguide structures where core regions are collectively surrounded by laterally adjacent cladding regions and cladding layers and methods of forming such structures.
    Type: Application
    Filed: August 10, 2011
    Publication date: March 15, 2012
    Applicants: PROMERUS, LLC, SUMITOMO BAKELITE COMPANY LIMITED
    Inventors: Koji CHOKI, Tetsuya Mori, Ramakrishna Ravikiran, Makoto Fujiwara, Keizo Takahama, Kei Watanabe, Hirotaka Nonaka, Yumiko Otake, Andrew Bell, Larry Rhodes, Dino Amoroso, Mutsuhiro Matsuyama
  • Patent number: 8053515
    Abstract: A polymer includes a first type of repeat unit represented by Formula I: where X is selected from —CH2—, —CH2—CH2—, or —O—; m is an integer from 0 to about 5; and where for the first type of repeat unit one of R1, R2, R3, and R4 is one of a maleimide containing group and for the second type of repeat unit one of R1, R2, R3, and R4 is a hindered aromatic group, a C8 or greater alkyl group, a C4 or greater halohydrocarbyl or perhalocarbyl group, a C7 or greater aralkyl group, or a heteroatom hydrocarbyl or halohydrocarbyl group.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: November 8, 2011
    Assignee: Promerus LLC
    Inventors: Edmund Elce, Andrew Bell, Brian Knapp, Hendra Ng, Larry F. Rhodes, Robert Shick, Wei Zhang, William DiMenna, Saikumar Jayaraman, Jianyong Jin, Rajesh Raja Puthenkovilakom, Ramakrishna Ravikiran, Xiaoming Wu, Etsu Takeuchi
  • Patent number: 8053166
    Abstract: Embodiments in accordance with the present invention provide waveguide structures and methods of forming such structures where core and laterally adjacent cladding regions are defined. Some embodiments of the present invention provide waveguide structures where core regions are collectively surrounded by laterally adjacent cladding regions and cladding layers and methods of forming such structures.
    Type: Grant
    Filed: September 3, 2009
    Date of Patent: November 8, 2011
    Assignees: Sumitomo Bakelite Co. Ltd., Promerus, LLC.
    Inventors: Koji Choki, Tetsuya Mori, Ramakrishna Ravikiran, Makoto Fujiwara, Keizo Takahama, Kei Watanabe, Hirotaka Nonaka, Yumiko Otake, Andrew Bell, Larry Rhodes, Dino Amoroso, Mutsuhiro Matsuyama
  • Patent number: 8021825
    Abstract: Embodiments in accordance with the present invention provide waveguide structures and methods of forming such structures where core and laterally adjacent cladding regions are defined. Some embodiments of the present invention provide waveguide structures where core regions are collectively surrounded by laterally adjacent cladding regions and cladding layers and methods of forming such structures.
    Type: Grant
    Filed: September 3, 2009
    Date of Patent: September 20, 2011
    Assignees: Sumitomo Bakelite Co., Ltd., Promerus, LLC.
    Inventors: Koji Choki, Tetsuya Mori, Ramakrishna Ravikiran, Makoto Fujiwara, Keizo Takahama, Kei Watanabe, Hirotaka Nonaka, Yumiko Otake, Andrew Bell, Larry Rhodes, Dino Amoroso, Mutsuhiro Matsuyama
  • Patent number: 7910674
    Abstract: Methods for the addition polymerization of cycloolefins using a cationic Group 10 metal complex and a weakly coordinating anion of the formula: [(R?)zM(L?)x(L?)y]b[WCA]d wherein [(R?)zM(L?)x(L?)y] is a cation complex where M represents a Group 10 transition metal; R? represents an anionic hydrocarbyl containing ligand; L? represents a Group 15 neutral electron donor ligand; L? represents a labile neutral electron donor ligand; x is 1 or 2; and y is 0, 1, 2, or 3; and z is 0 or 1, wherein the sum of x, y, and z is 4; and [WCA] represents a weakly coordinating counteranion complex; and b and d are numbers representing the number of times the cation complex and weakly coordinating counteranion complex are taken to balance the electronic charge on the overall catalyst complex.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: March 22, 2011
    Assignee: Promerus, LLC
    Inventors: Larry Funderburk Rhodes, Andrew Bell, Ramakrishna Ravikiran, John C. Fondran, Saikumar Jayaraman, Brian Leslie Goodall, Richard A. Mimna, John-Henry Lipian
  • Patent number: 7858721
    Abstract: Some embodiments in accordance with the present invention relate to norbornene-type polymers and to photosensitive dielectric resin compositions formed therefrom. Other embodiments relate to films formed from such compositions and to devices, such as electrical, electronic and optoelectronic devices, that encompass such films.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: December 28, 2010
    Assignee: Promerus LLC
    Inventors: Dino Amoroso, Brian Bedwell, Andrew Bell, Edmund Elce, Rajesh Raja Puthenkovilakom, Ramakrishna Ravikiran, Robert Shick, Xiaoming Wu, Hiroaki Makabe, Yasunori Takahashi, Etsu Takeuchi, Daoji Gan, Seok Ho Kang
  • Patent number: 7851575
    Abstract: A polymer comprising polycyclic repeating units having recurring ion conducting groups and optional crosslinkable groups is disclosed. The present invention provides the capability of tailoring polymers to impart unique properties to membranes fabricated from the polymers. Membranes comprising the polymers and methods for preparing the membranes and their use in ion conducting membranes, particularly in fuel cells, are also provided.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: December 14, 2010
    Assignee: Promerus LLC
    Inventors: Ramakrishna Ravikiran, Xiaoming Wu, Larry F. Rhodes, Robert A. Shick, Hiroko Nakano, Hirotaka Nonaka, Huabin Wang, Robert John Duff, Saikumar Jayaraman, John-Henry Lipian
  • Publication number: 20100282467
    Abstract: A process for recovering oil from an oil-bearing formation comprises introducing into said formation an aqueous composition comprising at least one sulfonated derivative of one or more internal olefins, said internal olefins being characterized by having low amounts of tri-substitution on the olefin bond, said sulfonated derivative being obtained by sulfonating a composition comprising internal olefins of the formula: R1R2C?CR3R4 wherein R1, R2, R3 and R4 are the same or different and are hydrogen or straight- or branched-chain, saturated hydrocarbyl groups and the total number of carbon atoms of R1, R2, R3 and R4 is 6 to 44 with the proviso that at least about 96 mole percent of R1 and R3 are straight- or branched-chain, saturated hydrocarbyl groups and at least about 96 mole percent of R2 and R4 are hydrogen.
    Type: Application
    Filed: May 5, 2010
    Publication date: November 11, 2010
    Applicant: Stepan Company
    Inventors: John C. Hutchison, Patrick Shane Wolfe, Thomas Edward Waldman, Ramakrishna Ravikiran
  • Patent number: 7820356
    Abstract: Embodiments in accordance with the present invention provide waveguide structures and methods of forming such structures where core and laterally adjacent cladding regions are defined. Some embodiments of the present invention provide waveguide structures where core regions are collectively surrounded by laterally adjacent cladding regions and cladding layers and methods of forming such structures.
    Type: Grant
    Filed: November 22, 2004
    Date of Patent: October 26, 2010
    Assignees: Sumitomo Bakelite Co. Ltd., Promerus, LLC
    Inventors: Koji Choki, Tetsuya Mori, Ramakrishna Ravikiran, Makoto Fujiwara, Keizo Takahama, Kei Watanabe, Hirotaka Nonaka, Yumiko Otake, Andrew Bell, Larry Rhodes, Dino Amoroso, Mutsuhiro Matsuyama
  • Publication number: 20100061688
    Abstract: Embodiments in accordance with the present invention provide waveguide structures and methods of forming such structures where core and laterally adjacent cladding regions are defined. Some embodiments of the present invention provide waveguide structures where core regions are collectively surrounded by laterally adjacent cladding regions and cladding layers and methods of forming such structures.
    Type: Application
    Filed: September 3, 2009
    Publication date: March 11, 2010
    Applicants: SUMITOMO BAKELITE CO., LTD., PROMERUS, LLC
    Inventors: Koji Choki, Tetsuya Mori, Ramakrishna Ravikiran, Makoto Fujiwara, Keizo Takahama, Kei Watanabe, Hirotaka Nonaka, Yumiko Otake, Andrew Bell, Larry Rhodes, Dino Amoroso, Mutsuhiro Matsuyama
  • Publication number: 20100062378
    Abstract: Embodiments in accordance with the present invention provide waveguide structures and methods of forming such structures where core and laterally adjacent cladding regions are defined. Some embodiments of the present invention provide waveguide structures where core regions are collectively surrounded by laterally adjacent cladding regions and cladding layers and methods of forming such structures.
    Type: Application
    Filed: September 3, 2009
    Publication date: March 11, 2010
    Applicants: SUMITOMO BAKELITE CO., LTD., PROMERUS, LLC
    Inventors: Koji Choki, Tetsuya Mori, Ramakrishna Ravikiran, Makoto Fujiwara, Keizo Takahama, Kei Watanabe, Hirotaka Nonaka, Yumiko Otake, Andrew Bell, Larry Rhodes, Dino Amoroso, Mutsuhiro Matsuyama
  • Publication number: 20090215976
    Abstract: Some embodiments in accordance with the present invention relate to norbornene-type polymers and to photosensitive dielectric resin compositions formed therefrom. Other embodiments relate to films formed from such compositions and to devices, such as electrical, electronic and optoelectronic devices, that encompass such films.
    Type: Application
    Filed: April 27, 2009
    Publication date: August 27, 2009
    Inventors: Dino Amoroso, Brian Bedwell, Andrew Bell, Edmund Elce, Rajesh Raja Puthenkovilakom, Ramakrishna Ravikiran, Robert Shick, Xiaoming Wu, Hiroaki Makabe, Yasunori Takahashi, Daoji Gan, Etsu Takeuchi, Seok Ho Kang
  • Patent number: 7524594
    Abstract: Some embodiments in accordance with the present invention relate to norbornene-type polymers and to photosensitive dielectric resin compositions formed therefrom. Other embodiments relate to films formed from such compositions and to devices, such as electrical, electronic and optoelectronic devices, that encompass such films.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: April 28, 2009
    Assignee: Promerus LLC
    Inventors: Dino Amoroso, Brian Bedwell, Andrew Bell, Edmund Elce, Rajesh Raja Puthenkovilakom, Ramakrishna Ravikiran, Robert Shick, Xiaoming Wu, Hiroaki Makabe, Yasunori Takahashi, Etsu Takeuchi, Daoji Gan, Seok Ho Kang
  • Publication number: 20080194740
    Abstract: A polymer includes a first type of repeat unit represented by Formula I: where X is selected from —CH2—, —CH2—CH2—, or —O—; m is an integer from 0 to about 5; and where for the first type of repeat unit one of R1, R2, R3, and R4 is one of a maleimide containing group and for the second type of repeat unit one of R1, R2, R3, and R4 is a hindered aromatic group, a C8 or greater alkyl group, a C4 or greater halohydrocarbyl or perhalocarbyl group, a C7 or greater aralkyl group, or a heteroatom hydrocarbyl or halohydrocarbyl group.
    Type: Application
    Filed: December 3, 2007
    Publication date: August 14, 2008
    Inventors: Edmund Elce, Andrew Bell, Brian Knapp, Hendra Ng, Larry F. Rhodes, Robert Shick, Wei Zhang, William DiMenna, Saikumar Jayaraman, Jianyong Jin, Rajesh Raja Puthenkovilakom, Ramakrishna Ravikiran, Xiaoming Wu, Etsu Takeuchi