Patents by Inventor Limin Xu
Limin Xu 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).
-
Publication number: 20240124762Abstract: A process for reducing the interfacial tension between a hydrocarbon fluid and a surfactant mixture during chemical enhanced oil recovery includes introducing a surfactant mixture solution comprising an anionic surfactant, a cationic surfactant, a nonionic surfactant, a brine solution, and a co-solvent to a hydrocarbon-bearing reservoir under conditions of a salinity of greater than or equal to 50,000 mg/L, a hardness of greater than or equal to 2,500 mg/L, and a temperature of greater than or equal to 90° C., thereby reducing the interfacial tension at a liquid-liquid interface of the hydrocarbon fluid and the surfactant mixture solution. The anionic surfactant comprises organo sulfate. The cationic surfactant comprises quaternary ammonium, brominated trimethylammonium, chloride trimethylammonium, or combinations thereof. The nonionic surfactant comprises polyoxyethylene fatty acid ester, phenylated ethoxylate, or combinations thereof.Type: ApplicationFiled: November 27, 2023Publication date: April 18, 2024Applicant: Saudi Arabian Oil CompanyInventors: Ming Han, Limin Xu
-
Publication number: 20240102931Abstract: A method includes providing a gelant including a cross-linkable polymer, a crosslinking agent and an aqueous fluid, adding one or more fluorescent rare earth elements to the gelant to provide a fluorescent gelant solution in which a fluorescence emission is quenched, and initiating crosslinking of the gelant to form a gel by heating the fluorescent gelant solution. The intensity of the fluorescence emission of the fluorescent gelant solution is monitored as an indicator of gelation status and a gelation point of the gelant may be identified based on the intensity of the fluorescent emission of the fluorescent gelant solution.Type: ApplicationFiled: May 5, 2022Publication date: March 28, 2024Applicants: SAUDI ARABIAN OIL COMPANY, ARAMCO FAR EAST (BEIJING) BUSINESS SERVICES CO., LTD.Inventors: Lyla Almaskeen, Abdulkareem AlSofi, Limin Xu
-
Patent number: 11942909Abstract: An amplifier includes an input circuit, an amplification circuit, and at least two feedback circuits. The input circuit is connected with an input end of the amplification circuit; an output end of the amplification circuit is connected with a first end of each of the feedback circuits respectively; a second end of each of the feedback circuits is connected with the input circuit respectively. The input circuit is configured to receive an input signal and a feedback signal; the amplification circuit is configured to amplify the input signal and the feedback signal to obtain an amplified signal. The feedback signal is fed back to the input circuit by feeding back at least a part of the amplified signal through a target feedback circuit; and the target feedback circuit is a feedback circuit that depends on the type of the input signal of the at least two feedback circuits.Type: GrantFiled: December 26, 2020Date of Patent: March 26, 2024Assignee: SMARTER MICROELECTRONICS (GUANG ZHOU) CO., LTD.Inventors: Limin Yu, Yongle Li, Cheng Xu
-
Publication number: 20240085328Abstract: Systems and methods are provided for excitation spectral microscopy using frame-synchronized acousto-optic scanning of fluorescent excitation wavelengths. Linear unmixing of the images of targets of components that are individually labeled with different fluorophores can be simultaneously imaged with high temporal resolution and low crosstalk and the local abundance of each fluorophore at each pixel can be quantified. Fluorophore decomposed micrographs of the sample can be obtained by rendering the abundance in each pixel as an image.Type: ApplicationFiled: October 11, 2023Publication date: March 14, 2024Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Ke Xu, Kun Chen, Rui Yan, Limin Xiang
-
Publication number: 20230303744Abstract: Provided is a quaternary ammonium surfmer and copolymers thereof. The surfmer may have the following general formula (I): N+—R1R2R3R4 (X?), where: R1 and R2 may independently be H or a C1-C3 alkyl, R3 may be a C19+ amidoalkyl group, R4 may be a C3-C6 alkyl having a terminal olefin double bond group, and X may be a halogen. Further provided is a method for synthesizing the quaternary ammonium surfmer, copolymers thereof, and a method for recovering hydrocarbons from a subterranean formation that may include injecting a treatment fluid comprising the quaternary ammonium surfmer or copolymers thereof into the subterranean formation.Type: ApplicationFiled: May 30, 2023Publication date: September 28, 2023Applicant: SAUDI ARABIAN OIL COMPANYInventors: Xuan Zhang, Ming Han, Limin Xu
-
Patent number: 11697700Abstract: Provided is a quaternary ammonium surfmer, that may have the following general formula (I): N+—R1R2R3R4 (X?), where: R1 and R2 may independently be H or a C1-C3 alkyl, R3 may be a C19+ amidoalkyl group, R4 may be a C3-C6 alkyl having a terminal olefin double bond group, and X may be a halogen. Further provided is a method for synthesizing the quaternary ammonium surfmer and a method for recovering hydrocarbons from a subterranean formation that may include injecting a treatment fluid comprising the quaternary ammonium surfmer into the subterranean formation.Type: GrantFiled: July 22, 2020Date of Patent: July 11, 2023Assignee: SAUDI ARABIAN OIL COMPANYInventors: Xuan Zhang, Ming Han, Limin Xu
-
Publication number: 20220267419Abstract: A human immunoglobulin against Methicillin-resistant Staphylococcus aureus, and human immunoglobulin against Methicillin-resistant Staphylococcus aureus is prepared by collecting plasma of a healthy plasma donor immunized with Methicillin-resistant Staphylococcus aureus vaccine, wherein the Staphylococcus aureus vaccine has a valence of antigen mHla of no less than 1:3,200, valence of antigen IsdB of no less than 1:1,600, valence of antigen MntC of no less than 1:1,600, valence of antigen mSEB of no less than 1:6,400, and valence of antigen SpA5 of no less than 1:400, and total content of IgG monomers and dimers is over 90.0%. The human immunoglobulin against Methicillin-resistant Staphylococcus aureus has high valence and high purity, which can not only have good effects for preventing and treating Methicillin-resistant Staphylococcus aureus infection, but also avoid a problem of drug resistance caused by antibiotic treatment, and has important clinical significance and broad market prospects.Type: ApplicationFiled: June 24, 2020Publication date: August 25, 2022Applicant: Chengdu Olymvax Biopharmaceuticals Inc.Inventors: Quanming Zou, Shaowen Fan, Hao Zeng, Feng Yang, Qiang Wu, Limin Xu, Yongjun Ji, Fan Fan
-
Patent number: 11350023Abstract: Autofocus methods and devices are provided. The method includes: controlling a lens group to move at a first speed, and photographing an image at a preset photographing frequency when the lens group moves at the first speed; when a definition of the image photographed by the lens group in a state of moving at the first speed satisfies a preset condition, reducing a moving speed of the lens group to a second speed, and photographing images at the preset photographing frequency when the lens group moves at the second speed; and when a first image with a highest definition is determined in the images photographed by the lens group in a state of moving at the second speed, controlling the lens group to decelerate, and controlling, when the lens group stops moving, the lens group to return to a position of the lens group where the first image was photographed.Type: GrantFiled: January 28, 2019Date of Patent: May 31, 2022Assignee: HANGZHOU HIKVISION DIGITAL TECHNOLOGY CO., LTD.Inventor: Limin Xu
-
Patent number: 11254855Abstract: Surfactant mixtures include a cationic surfactant, an anionic surfactant, and a nonionic surfactant in a brine solution. The cationic surfactant may include at least one quaternary ammonium, at least one brominated trimethylammonium, or combinations thereof. The anionic surfactant may include at least one organosulfate. The nonionic surfactant may include the nonionic surfactant comprised of a polyoxyethylene fatty acid ester, a phenylated ethoxylate, or combinations thereof. The surfactant mixtures may be incorporated into methods for reducing the interfacial tension between the surfactant mixture and oily fluids during chemical enhanced oil recovery. The methods for reducing the interfacial tension may include introducing the surfactant mixture comprising a cationic surfactant, an anionic surfactant, and a nonionic surfactant in a brine solution to a hydrocarbon-bearing reservoir, thereby reducing the interfacial tension at a liquid-liquid interface of the surfactant mixture and the fluid.Type: GrantFiled: November 14, 2019Date of Patent: February 22, 2022Assignee: Saudi Arabian Oil CompanyInventors: Limin Xu, Ming Han, Alhasan Fuseni, Dongqing Cao
-
Publication number: 20220025090Abstract: Provided is a quaternary ammonium surfmer, that may have the following general formula (I): N+—R1R2R3R4 (X?), where: R1 and R2 may independently be H or a C1-C3 alkyl, R3 may be a C19+ amidoalkyl group, R4 may be a C3-C6 alkyl having a terminal olefin double bond group, and X may be a halogen. Further provided is a method for synthesizing the quaternary ammonium surfmer and a method for recovering hydrocarbons from a subterranean formation that may include injecting a treatment fluid comprising the quaternary ammonium surfmer into the subterranean formation.Type: ApplicationFiled: July 22, 2020Publication date: January 27, 2022Applicant: SAUDI ARABIAN OIL COMPANYInventors: Xuan Zhang, Ming Han, Limin Xu
-
Publication number: 20210147744Abstract: Surfactant mixtures include a cationic surfactant, an anionic surfactant, and a nonionic surfactant in a brine solution. The cationic surfactant may include at least one quaternary ammonium, at least one brominated trimethylammonium, or combinations thereof. The anionic surfactant may include at least one organosulfate. The nonionic surfactant may include the nonionic surfactant comprised of a polyoxyethylene fatty acid ester, a phenylated ethoxylate, or combinations thereof. The surfactant mixtures may be incorporated into methods for reducing the interfacial tension between the surfactant mixture and oily fluids during chemical enhanced oil recovery. The methods for reducing the interfacial tension may include introducing the surfactant mixture comprising a cationic surfactant, an anionic surfactant, and a nonionic surfactant in a brine solution to a hydrocarbon-bearing reservoir, thereby reducing the interfacial tension at a liquid-liquid interface of the surfactant mixture and the fluid.Type: ApplicationFiled: November 14, 2019Publication date: May 20, 2021Applicant: Saudi Arabian Oil CompanyInventors: Limin Xu, Ming Han, Alhasan Fuseni, Dongqing Cao
-
Patent number: 10981458Abstract: A homopolar DC electromagnetic transmission (HET) and an application system thereof are provided. The HET includes two rotors, a stator, an external auxiliary system and an adjustment control system. Each of the rotors has one or more axisymmetric rotor magnetic conductors, and the stator has one or more direct current magnet exciting coils wound around an axis of a rotation shaft. A main magnetic circuit is guided to be a closed ring. The HET includes at least two main magnetic circuits. The HET includes a closed main current loop. The loop is connected with all the rotor magnetic conductors, a rotor electric conductor, a dynamic/static circuit connecting medium, stator conductors and stator magnetic conductors in series or in series and parallel. A direction of main current on the rotor magnetic conductors is perpendicular to a direction of magnetic flux (?) on meridian plane.Type: GrantFiled: May 30, 2018Date of Patent: April 20, 2021Inventor: Limin Xu
-
Publication number: 20210006707Abstract: An autofocus method and device, related to the field of electronics are provided. The method includes: controlling a lens group to move at a first speed, and photographing an image at a preset photographing frequency when the lens group moves at the first speed; when a definition of the image photographed by the lens group in a state of moving at the first speed satisfies a preset condition, reducing a moving speed of the lens group to a second speed, and photographing images at the preset photographing frequency when the lens group moves at the second speed; and when a first image with a highest definition is determined in the images photographed by the lens group in a state of moving at the second speed, controlling the lens group to decelerate, and controlling, when the lens group stops moving, the lens group to return to a position of the lens group where the first image was photographed.Type: ApplicationFiled: January 28, 2019Publication date: January 7, 2021Inventor: Limin XU
-
Publication number: 20180273016Abstract: A homopolar DC electromagnetic transmission (HET) and an application system thereof are provided. The HET includes two rotors, a stator, an external auxiliary system and an adjustment control system. Each of the rotors has one or more axisymmetric rotor magnetic conductors, and the stator has one or more direct current magnet exciting coils wound around an axis of a rotation shaft. A main magnetic circuit is guided to be a closed ring. The HET includes at least two main magnetic circuits. The HET includes a closed main current loop. The loop is connected with all the rotor magnetic conductors, a rotor electric conductor, a dynamic/static circuit connecting medium, stator conductors and stator magnetic conductors in series or in series and parallel. A direction of main current on the rotor magnetic conductors is perpendicular to a direction of magnetic flux (?) on meridian plane.Type: ApplicationFiled: May 30, 2018Publication date: September 27, 2018Inventor: Limin XU
-
Patent number: 9802848Abstract: The invention relates to a method of circular use of waste brine produced in the manufacture process of MDI, comprising the following steps: (1) the waste brine produced in the manufacture process of MDI is subjected to a high-gravity extraction and then to a column extraction, wherein said waste brine contains aniline, diaminodiphenylmethane and polyamine; (2) the waste brine from step (1) is transmitted to a stripping tower for steam stripping; (3) the waste brine from the stripping tower of step (2) and a chemical oxidant are transmitted to an oxidation reactor to which air is blown for aeration; (4) the waste brine after the treatment of step (3) is transmitted to an absorption tower for absorption. The invention makes the salt water have TOC of less than 8 ppm and TN of less than 2.5 ppm and achieves regeneration of resources in the waste brine such as sodium chloride and water and the like for circular use.Type: GrantFiled: September 17, 2009Date of Patent: October 31, 2017Assignee: WANHUA CHEMICAL (NINGBO) CO., LTD.Inventors: Hongke Zhang, Weiqi Hua, Xiaogao Liu, Zhenhua Zhao, Shuchang Sun, Jiansheng Ding, Jianfeng Chen, Pengyuan Zhang, Haikui Zou, Guangwen Chu, Limin Xu
-
Publication number: 20120168375Abstract: The invention relates to a method of circular use of waste brine produced in the manufacture process of MDI, comprising the following steps: (1) the waste brine produced in the manufacture process of MDI is subjected to a high-gravity extraction and then to a column extraction, wherein said waste brine contains aniline, diaminodiphenylmethane and polyamine; (2) the waste brine from step (1) is transmitted to a stripping tower for steam stripping; (3) the waste brine from the stripping tower of step (2) and a chemical oxidant are transmitted to an oxidation reactor to which air is blown for aeration; (4) the waste brine after the treatment of step (3) is transmitted to an absorption tower for absorption. The invention makes the salt water have TOC of less than 8 ppm and TN of less than 2.5 ppm and achieves regeneration of resources in the waste brine such as sodium chloride and water and the like for circular use.Type: ApplicationFiled: September 17, 2009Publication date: July 5, 2012Applicants: Beijing University of Chemical Technology, Ningbo Polyurethanes Co., Ltd.Inventors: Hongke Zhang, Weiqi Hua, Xiaogao Liu, Zhenhua Zhao, Shuchang Sun, Jiansheng Ding, Jianfeng Chen, Pengyuan Zhang, Haikui Zou, Guangwen Chu, Limin Xu
-
Patent number: 7893301Abstract: The present invention provides a method of preparing polymethylene-polyphenyl-polyamine (briefly referred to as polyamine, DAM), in which a high gravity rotating bed is used as the mixing reactor of formaldehyde and aniline hydrochloride, the mixing solution of aniline hydrochloride and circulation solution and the formaldehyde are fed into the high gravity rotating bed reactor proportionally to carry out mixing and condensation reaction under a condition of a very high gravity; the materials leaving the high gravity rotating bed reactor is introduced into a stirred vessel to proceed with the pre-condensation reaction and obtain a condensation solution; and the process steps of heating, molecular rearrangement, neutralization, water washing and purification, etc. are completed to obtain the refined DAM.Type: GrantFiled: October 16, 2007Date of Patent: February 22, 2011Assignees: Ningbo Wanhua Polyurethanes Co., Ltd., Beijing University of Chemical TechnologyInventors: Jiansheng Ding, Jianfeng Chen, Hongke Zhang, Haikui Zou, Weiqi Hua, Pengyuan Zhang, Shuchang Sun, Guangwen Chu, Limin Xu
-
Publication number: 20080249261Abstract: The present invention provides a method of preparing polymethylene-polyphenyl-polyamine (briefly referred to as polyamine, DAM), in which a high gravity rotating bed is used as the mixing reactor of formaldehyde and aniline hydrochloride, the mixing solution of aniline hydrochloride and circulation solution and the formaldehyde are fed into the high gravity rotating bed reactor proportionally to carry out mixing and condensation reaction under a condition of a very high gravity; the materials leaving the high gravity rotating bed reactor is introduced into a stirred vessel to proceed with the pre-condensation reaction and obtain a condensation solution; and the process steps of heating, molecular rearrangement, neutralization, water washing and purification, etc. are completed to obtain the refined DAM.Type: ApplicationFiled: October 16, 2007Publication date: October 9, 2008Inventors: Jiansheng Ding, Jianfeng Chen, Hongke Zhang, Haikui Zou, Weiqi Hua, Pengyuan Zhang, Shuchang Sun, Guangwen Chu, Limin Xu
-
Patent number: D959807Type: GrantFiled: April 30, 2021Date of Patent: August 9, 2022Inventor: Limin Xu