Abstract: Provided are a method for preparing an oligomer and an apparatus for preparing an oligomer. The method for preparing an oligomer includes performing an oligomerization reaction by feeding a feed stream containing a monomer to a reactor; feeding a first discharge stream of the reactor to a first separation device, and feeding a second discharge stream of the reactor to a second separation device; feeding a lower discharge stream of the second separation device to a third separation device; feeding an upper discharge stream containing the monomer of the third separation device to a monomer dissolution device and dissolving the upper discharge stream in a solvent fed to the monomer dissolution device; and feeding a discharge stream of the monomer dissolution device to the reactor.

Abstract: An electrode performance evaluation system and an electrode performance evaluation method is disclosed. The method includes acquiring impedance measurement data for different frequencies by applying an alternating current signal to an electrode assembly including an electrode which is immersed in an electrolyte solution, calculating impedance calculation data for different frequencies while changing the frequency of an impedance equation corresponding to a circuit model of the electrode assembly, calculating the resistance value of ion bulk resistance in the electrolyte solution using the ion conductivity of the electrolyte solution, the area of the electrode and the thickness and porosity of an active material layer of the electrode, and determining effective tortuosity as a factor of the electrode performance based on the impedance measurement data for different frequencies, the impedance calculation data for different frequencies and the resistance value of the ion bulk resistance.

Abstract: A method and an apparatus for preparing an alpha-olefin. The method includes supplying a feed stream including a gaseous ethylene monomer to a monomer dissolution device to dissolve the feed stream in a solvent and form a liquid ethylene monomer, and supplying a feed stream including the liquid ethylene monomer as a discharge stream to a reactor, thereby removing heat of dissolution of the gaseous ethylene monomer outside of the reactor, and decreasing an amount of a refrigerant used in an alpha-olefin production process to improve economic feasibility.

Abstract: A method and an apparatus for preparing an oligomer, the method including supplying a feed stream including a monomer to a reactor to perform an oligomerization reaction, recovering unreacted monomer, and dissolving the recovered unreacted monomer in a solvent in a monomer dissolution device and supplying a discharge stream from the monomer dissolution device to the reactor. The method and the apparatus provide reduced investment costs and improved economic feasibility as there is no need to use a refrigerant at a very low temperature or install a separate compressor to recover and reuse the unreacted monomer in an oligomer production process.

Abstract: A method and an apparatus for preparing an alpha-olefin. The method includes supplying a feed stream including a gaseous ethylene monomer to a monomer dissolution device to dissolve the feed stream in a solvent and form a liquid ethylene monomer, and supplying a feed stream including the liquid ethylene monomer as a discharge stream to a reactor, thereby removing heat of dissolution of the gaseous ethylene monomer outside of the reactor, and decreasing an amount of a refrigerant used in an alpha-olefin production process to improve economic feasibility.

Abstract: Provided is a method for manufacturing a positive electrode for a secondary battery, the method including applying a first positive electrode slurry including a first positive electrode active material on a positive electrode current collector, forming a first positive electrode mixture layer by primarily rolling the current collector applied with the first positive electrode slurry, applying a second positive electrode slurry including a second positive electrode active material on the above-formed first positive electrode mixture layer, and forming a second positive electrode mixture layer on which the first positive electrode mixture layer is laminated by secondarily rolling the first positive electrode mixture layer applied with the second positive electrode slurry.

Abstract: Provided is a positive electrode for a secondary battery, the positive electrode including a positive electrode current collector, a first positive electrode mixture layer laminated on the positive electrode current collector and including a first positive electrode active material and a first conductive material, and a second positive electrode mixture layer laminated on the first positive electrode mixture layer and including a second positive electrode active material and a second conductive material, wherein the average particle diameter (D50) of the second positive electrode active material is 5 to 80% of the average particle diameter (D50) of the first positive electrode active material, and the ratio of the specific surface area of the second conductive material to the specific surface area of the second positive electrode active material is 9 or less.

Abstract: An electrode performance evaluation system and an electrode performance evaluation method is disclosed. The method includes acquiring impedance measurement data for different frequencies by applying an alternating current signal to an electrode assembly including an electrode which is immersed in an electrolyte solution, calculating impedance calculation data for different frequencies while changing the frequency of an impedance equation corresponding to a circuit model of the electrode assembly, calculating the resistance value of ion bulk resistance in the electrolyte solution using the ion conductivity of the electrolyte solution, the area of the electrode and the thickness and porosity of an active material layer of the electrode, and determining effective tortuosity as a factor of the electrode performance based on the impedance measurement data for different frequencies, the impedance calculation data for different frequencies and the resistance value of the ion bulk resistance.

Abstract: Disclosed is an optical fiber including a plasmonic optical filter with a closed curved shape provided at, at least portion thereof. A method of manufacturing the plasmonic optical filter includes a step of exposing a core, a step of forming a thin metal film on the core through physical vapor deposition while rotating the core in a circumferential direction after changing a rotation axis of the core, and a step of patterning nanopatterns on the cylinder-shaped thin metal film using focused ion beam technique assisted with endpoint detection method. Due to such constitutions, an active area to generate an optical signal for optical sensor can be increased.

Abstract: The present invention relates to an electrode for a secondary battery having improved safety, a method for manufacturing the electrode, and a secondary battery including the electrode. The secondary battery according to the present invention includes a plurality of apertures that penetrate a current collector and an electrode active material layer in a thickness direction. The electrode may improve safety by preventing or minimizing the occurrence of ignition or explosion when a sharp object such as a nail penetrates into the interior of a battery, thereby improving safety of the battery.

Abstract: Provided is an electrode, comprising: an electrode current collector, a metal nanowire formed on a surface of the electrode current collector, and a conductive layer surrounding the outside of the metal nanowire, wherein a gap is formed between the metal nanowire and the conductive layer, so that the metal nanowire and the conductive layer are spaced apart from each other without direct contact between them.

Abstract: Disclosed is a positive electrode for a lithium secondary battery, which includes: a positive electrode current collector; and a positive electrode active material layer including an upper layer portion and a lower layer portion, wherein each of the upper layer portion and the lower layer portion of the positive electrode active material layer includes a positive electrode active material, binder polymer and a conductive material, and the positive electrode active material has an electroconductivity of 0.0001-0.0004 S/cm, and the content of the conductive material contained in the lower layer portion is 10-59 parts by weight based on 100 parts by weight of the content of the conductive material contained in the upper layer portion, or the positive electrode active material has an electroconductivity of 0.008-0.

Abstract: Disclosed is an optical fiber including a plasmonic optical filter with a closed curved shape provided at, at least portion thereof. A method of manufacturing the plasmonic optical filter includes a step of exposing a core, a step of forming a thin metal film on the core through physical vapor deposition while rotating the core in a circumferential direction after changing a rotation axis of the core, and a step of patterning nanopatterns on the cylinder-shaped thin metal film using focused ion beam technique assisted with endpoint detection method. Due to such constitutions, an active area to generate an optical signal for optical sensor can be increased.

Abstract: Disclosed is an optical fiber including a plasmonic optical filter with a closed curved shape provided at, at least portion thereof. A method of manufacturing the plasmonic optical filter includes a step of exposing a core, a step of forming a thin metal film on the core through physical vapor deposition while rotating the core in a circumferential direction after changing a rotation axis of the core, and a step of patterning nanopatterns on the cylinder-shaped thin metal film using focused ion beam technique assisted with endpoint detection method. Due to such constitutions, an active area to generate an optical signal for optical sensor can be increased.

Abstract: Provided is a positive electrode for a secondary battery, the positive electrode including a positive electrode current collector, a first positive electrode mixture layer laminated on the positive electrode current collector and including a first positive electrode active material and a first conductive material, and a second positive electrode mixture layer laminated on the first positive electrode mixture layer and including a second positive electrode active material and a second conductive material, wherein the average particle diameter (D50) of the second positive electrode active material is 5 to 80% of the average particle diameter (D50) of the first positive electrode active material, and the ratio of the specific surface area of the second conductive material to the specific surface area of the second positive electrode active material is 9 or less.

Abstract: Provided is a method for manufacturing a positive electrode for a secondary battery, the method including applying a first positive electrode slurry including a first positive electrode active material on a positive electrode current collector, forming a first positive electrode mixture layer by primarily rolling the current collector applied with the first positive electrode slurry, applying a second positive electrode slurry including a second positive electrode active material on the above-formed first positive electrode mixture layer, and forming a second positive electrode mixture layer on which the first positive electrode mixture layer is laminated by secondarily rolling the first positive electrode mixture layer applied with the second positive electrode slurry.

Abstract: Provided is an electrode, comprising: an electrode current collector, a metal nanowire formed on a surface of the electrode current collector, and a conductive layer surrounding the outside of the metal nanowire, wherein a gap is formed between the metal nanowire and the conductive layer, so that the metal nanowire and the conductive layer are spaced apart from each other without direct contact between them.

Abstract: Disclosed is an optical fiber including a plasmonic optical filter with a closed curved shape provided at, at least portion thereof. A method of manufacturing the plasmonic optical filter includes a step of exposing a core, a step of forming a thin metal film on the core through physical vapor deposition while rotating the core in a circumferential direction after changing a rotation axis of the core, and a step of patterning nanopatterns on the cylinder-shaped thin metal film using focused ion beam technique assisted with endpoint detection method. Due to such constitutions, an active area to generate an optical signal for optical sensor can be increased.