Patents by Inventor Sang-Hyon Chu
Sang-Hyon Chu 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: 10934028Abstract: A lightweight flexible BNNT mat or fabric provides improved thermal stability and shielding capabilities under a hypersonic thermal flux. The BNNT mat reduces the stagnation temperature and maintains a low regression rate. An in-situ passivation layer may be formed on the BNNT mat or fabric under high thermal flux. The passivation layer minimizes or prevents penetration of the atmosphere (air or gas) as well as heat and radiation through the thickness of the BNNT material, and it effectively diffuses heat throughout the mat or fabric laterally and radially to minimize localized excessive heat. A BNNT mat according to the present disclosure may also efficiently transfer heat from the BNNT material via radiation due to the high thermal emissivity (0.92) of the BNNT material.Type: GrantFiled: November 15, 2017Date of Patent: March 2, 2021Assignee: U.S.A. as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: John-Andrew S. Hocker, Cheol Park, Sang-Hyon Chu, Jin Ho Kang, Catharine C. Fay
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Publication number: 20180134418Abstract: A lightweight flexible BNNT mat or fabric provides improved thermal stability and shielding capabilities under a hypersonic thermal flux. The BNNT mat reduces the stagnation temperature and maintains a low regression rate. An in-situ passivation layer may be formed on the BNNT mat or fabric under high thermal flux. The passivation layer minimizes or prevents penetration of the atmosphere (air or gas) as well as heat and radiation through the thickness of the BNNT material, and it effectively diffuses heat throughout the mat or fabric laterally and radially to minimize localized excessive heat. A BNNT mat according to the present disclosure may also efficiently transfer heat from the BNNT material via radiation due to the high thermal emissivity (0.92) of the BNNT material.Type: ApplicationFiled: November 15, 2017Publication date: May 17, 2018Inventors: John-Andrew S. Hocker, Cheol Park, Sang-Hyon Chu, Jin Ho Kang, Catharine C. Fay
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Patent number: 9446953Abstract: Metal and semiconductor nanoshells, particularly transition metal nanoshells, are fabricated using dendrimer molecules. Metallic colloids, metallic ions or semiconductors are attached to amine groups on the dendrimer surface in stabilized solution for the surface seeding method and the surface seedless method, respectively. Subsequently, the process is repeated with additional metallic ions or semiconductor, a stabilizer, and NaBH4 to increase the wall thickness of the metallic or semiconductor lining on the dendrimer surface. Metallic or semiconductor ions are automatically reduced on the metallic or semiconductor nanoparticles causing the formation of hollow metallic or semiconductor nanoparticles. The void size of the formed hollow nanoparticles depends on the dendrimer generation. The thickness of the metallic or semiconductor thin film around the dendrimer depends on the repetition times and the size of initial metallic or semiconductor seeds.Type: GrantFiled: December 4, 2008Date of Patent: September 20, 2016Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Jae-Woo Kim, Sang H. Choi, Sr., Peter T. Lillehei, Sang-Hyon Chu, Yeonjoon Park, Glen C. King, James R. Elliott
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Patent number: 8529825Abstract: A new fabrication method for nanovoids-imbedded bismuth telluride (Bi—Te) material with low dimensional (quantum-dots, quantum-wires, or quantum-wells) structure was conceived during the development of advanced thermoelectric (TE) materials. Bismuth telluride is currently the best-known candidate material for solid-state TE cooling devices because it possesses the highest TE figure of merit at room temperature. The innovative process described here allows nanometer-scale voids to be incorporated in Bi—Te material. The final nanovoid structure such as void size, size distribution, void location, etc. can be also controlled under various process conditions.Type: GrantFiled: December 3, 2010Date of Patent: September 10, 2013Assignees: National Institute of Aerospace Associates, The United States of America as represented by the Administration of NASAInventors: Sang-Hyon Chu, Sang H. Choi, Jae-Woo Kim, Yeonjoon Park, James R. Elliott, Glen C. King, Diane M. Stoakley
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Patent number: 8217143Abstract: Metal nanoshells are fabricated by admixing an aqueous solution of metal ions with an aqueous solution of apoferritin protein molecules, followed by admixing an aqueous solution containing an excess of an oxidizing agent for the metal ions. The apoferritin molecules serve as bio-templates for the formation of metal nanoshells, which form on and are bonded to the inside walls of the hollow cores of the individual apoferritin molecules. Control of the number of metal atoms which enter the hollow core of each individual apoferritin molecule provides a hollow metal nonparticle, or nanoshell, instead of a solid spherical metal nanoparticle.Type: GrantFiled: July 12, 2007Date of Patent: July 10, 2012Assignees: National Institute of Aerospace Associates, The United States of America as represented by the Administration of NASAInventors: Jae-Woo Kim, Sang H. Choi, Peter T. Lillehei, Sang-Hyon Chu, Yeonjoon Park, Glen C. King, James R. Elliott, Jr.
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Patent number: 8089677Abstract: A dynamic optical grating device and associated method for modulating light is provided that is capable of controlling the spectral properties and propagation of light without moving mechanical components by the use of a dynamic electric and/or magnetic field. By changing the electric field and/or magnetic field, the index of refraction, the extinction coefficient, the transmittivity, and the reflectivity of the optical grating device may be controlled in order to control the spectral properties of the light reflected or transmitted by the device.Type: GrantFiled: June 8, 2008Date of Patent: January 3, 2012Assignee: The United States of America as represented by the Administrator of the National Aeuronautics and Space AdministrationInventors: Yeonjoon Park, Sang H. Choi, Glen C. King, Sang-Hyon Chu
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Patent number: 8083986Abstract: A novel method to prepare an advanced thermoelectric material has hierarchical structures embedded with nanometer-sized voids which are key to enhancement of the thermoelectric performance. Solution-based thin film deposition technique enables preparation of stable film of thermoelectric material and void generator (voigen). A subsequent thermal process creates hierarchical nanovoid structure inside the thermoelectric material. Potential application areas of this advanced thermoelectric material with nanovoid structure are commercial applications (electronics cooling), medical and scientific applications (biological analysis device, medical imaging systems), telecommunications, and defense and military applications (night vision equipments).Type: GrantFiled: December 4, 2008Date of Patent: December 27, 2011Assignees: National Institute of Aerospace Associates, The United States of America as represented by the Adminstration of NASAInventors: Sang Hyouk Choi, Yeonjoon Park, Sang-Hyon Chu, James R. Elliott, Glen C. King, Jae-Woo Kim, Peter T. Lillehei, Diane M. Stoakley
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Patent number: 8020805Abstract: A new High Altitude Airship (HAA) capable of various extended applications and mission scenarios utilizing inventive onboard energy harvesting and power distribution systems. The power technology comprises an advanced thermoelectric (ATE) thermal energy conversion system. The high efficiency of multiple stages of ATE materials in a tandem mode, each suited for best performance within a particular temperature range, permits the ATE system to generate a high quantity of harvested energy for the extended mission scenarios. When the figure of merit 5 is considered, the cascaded efficiency of the three-stage ATE system approaches an efficiency greater than 60 percent.Type: GrantFiled: July 31, 2007Date of Patent: September 20, 2011Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Sang H. Choi, James R. Elliott, Jr., Glen C. King, Yeonjoon Park, Jae-Woo Kim, Sang-Hyon Chu
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Publication number: 20110117690Abstract: A new fabrication method for nanovoids-imbedded bismuth telluride (Bi—Te) material with low dimensional (quantum-dots, quantum-wires, or quantum-wells) structure was conceived during the development of advanced thermoelectric (TE) materials. Bismuth telluride is currently the best-known candidate material for solid-state TE cooling devices because it possesses the highest TE figure of merit at room temperature. The innovative process described here allows nanometer-scale voids to be incorporated in Bi—Te material. The final nanovoid structure such as void size, size distribution, void location, etc. can be also controlled under various process conditions.Type: ApplicationFiled: December 3, 2010Publication date: May 19, 2011Applicants: National Institute of Aerospace Associates, and Space AdministrationInventors: Sang-Hyon Chu, Sang Hyouk Choi, Jae-Woo Kim, Yeonjoon Park, James R. Elliott, JR., Glen C. King, Diane M. Stoakley
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Publication number: 20090303598Abstract: A dynamic optical grating device and associated method for modulating light is provided that is capable of controlling the spectral properties and propagation of light without moving mechanical components by the use of a dynamic electric and/or magnetic field. By changing the electric field and/or magnetic field, the index of refraction, the extinction coefficient, the transmittivity, and the reflectivity of the optical grating device may be controlled in order to control the spectral properties of the light reflected or transmitted by the device.Type: ApplicationFiled: June 8, 2008Publication date: December 10, 2009Applicant: USA as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Yeonjoon Park, Sang H. Choi, Glen C. King, Sang-Hyon Chu
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Publication number: 20090203196Abstract: Metal and semiconductor nanoshells, particularly transition metal nanoshells, are fabricated using dendrimer molecules. Metallic colloids, metallic ions or semiconductors are attached to amine groups on the dendrimer surface in stabilized solution for the surface seeding method and the surface seedless method, respectively. Subsequently, the process is repeated with additional metallic ions or semiconductor, a stabilizer, and NaBH4 to increase the wall thickness of the metallic or semiconductor lining on the dendrimer surface. Metallic or semiconductor ions are automatically reduced on the metallic or semiconductor nanoparticles causing the formation of hollow metallic or semiconductor nanoparticles. The void size of the formed hollow nanoparticles depends on the dendrimer generation. The thickness of the metallic or semiconductor thin film around the dendrimer depends on the repetition times and the size of initial metallic or semiconductor seeds.Type: ApplicationFiled: December 4, 2008Publication date: August 13, 2009Applicants: National Institute of Aerospace Associates, USA as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Jae-Woo KIM, Sang H. CHOI, SR., Peter T. LILLEHEI, Sang-Hyon CHU, Yeonjoon PARK, Glen C. KING, James R. ELLIOTT, JR.
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Publication number: 20090185942Abstract: A novel method to prepare an advanced thermoelectric material has hierarchical structures embedded with nanometer-sized voids which are key to enhancement of the thermoelectric performance. Solution-based thin film deposition technique enables preparation of stable film of thermoelectric material and void generator (voigen). A subsequent thermal process creates hierarchical nanovoid structure inside the thermoelectric material. Potential application areas of this advanced thermoelectric material with nanovoid structure are commercial applications (electronics cooling), medical and scientific applications (biological analysis device, medical imaging systems), telecommunications, and defense and military applications (night vision equipments).Type: ApplicationFiled: December 4, 2008Publication date: July 23, 2009Applicants: National Institute of Aerospace Associates, Space AdminstrationInventors: Sang Hyouk Choi, SR., Yeonjoon Park, Sang-Hyon Chu, James R. Elliott, Glen C. King, Jae-Woo Kim, Peter T. Lillehei, Diane M. Stoakley
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Patent number: 7510802Abstract: A thin-film electrode for a bio-nanobattery is produced by consecutively depositing arrays of a ferritin protein on a substrate, employing a spin self-assembly procedure. By this procedure, a first ferritin layer is first formed on the substrate, followed by building a second, oppositely-charged ferritin layer on the top of the first ferritin layer to form a bilayer structure. Oppositely-charged ferritin layers are subsequently deposited on top of each other until a desired number of bilayer structures is produced. An ordered, uniform, stable and robust, thin-film electrode material of enhanced packing density is presented, which provides optimal charge density for the bio-nanobattery.Type: GrantFiled: March 9, 2006Date of Patent: March 31, 2009Assignees: National Institute of Aerospace Associates, The United States of America as represented by the Administration of NASAInventors: Sang-Hyon Chu, Sang H. Choi, Jae-Woo Kim, Peter T. Lillehei, Yeonjoon Park, Glen C. King, James R. Elliott, Jr.
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Publication number: 20090072078Abstract: A new High Altitude Airship (HAA) capable of various extended applications and mission scenarios utilizing inventive onboard energy harvesting and power distribution systems. The power technology comprises an advanced thermoelectric (ATE) thermal energy conversion system. The high efficiency of multiple stages of ATE materials in a tandem mode, each suited for best performance within a particular temperature range, permits the ATE system to generate a high quantity of harvested energy for the extended mission scenarios. When the figure of merit 5 is considered, the cascaded efficiency of the three-stage ATE system approaches an efficiency greater than 60 percent.Type: ApplicationFiled: July 31, 2007Publication date: March 19, 2009Applicants: Space AdministrationInventors: Sang H. Choi, James R. Elliott, JR., Glen C. King, Yeonjoon Park, Jae-Woo Kim, Sang-Hyon Chu
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Publication number: 20080014621Abstract: Metal nanoshells are fabricated by admixing an aqueous solution of metal ions with an aqueous solution of apoferritin protein molecules, followed by admixing an aqueous solution containing an excess of an oxidizing agent for the metal ions. The apoferritin molecules serve as bio-templates for the formation of metal nanoshells, which form on and are bonded to the inside walls of the hollow cores of the individual apoferritin molecules. Control of the number of metal atoms which enter the hollow core of each individual apoferritin molecule provides a hollow metal nonparticle, or nanoshell, instead of a solid spherical metal nanoparticle.Type: ApplicationFiled: July 12, 2007Publication date: January 17, 2008Applicant: National Institute of Aerospace AssociatesInventors: Jae-Woo Kim, Sang H. Choi, Peter T. Lillehei, Sang-Hyon Chu, Yeonjoon Park, Glen C. King, James R. Elliott
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Publication number: 20070134552Abstract: A thin-film electrode for a bio-nanobattery is produced by consecutively depositing arrays of a ferritin protein on a substrate, employing a spin self-assembly procedure. By this procedure, a first ferritin layer is first formed on the substrate, followed by building a second, oppositely-charged ferritin layer on the top of the first ferritin layer to form a bilayer structure. Oppositely-charged ferritin layers are subsequently deposited on top of each other until a desired number of bilayer structures is produced. An ordered, uniform, stable and robust, thin-film electrode material of enhanced packing density is presented, which provides optimal charge density for the bio-nanobattery.Type: ApplicationFiled: March 9, 2006Publication date: June 14, 2007Applicants: National Institute of Aerospace Associates, Space AdministrationInventors: Sang-Hyon Chu, Sang Choi, Jae-Woo Kim, Peter Lillehei, Yeonjoon Park, Glen King, James Elliott