Abstract: disclosure A positive electrode for a lithium secondary battery includes a positive electrode collector; and a positive electrode active material layer which is formed on at least one surface of the positive electrode collector and includes a positive electrode active material, wherein the positive electrode active material layer has a pore volume of 7.0×10?3·cm3/g to 8.0×10?3·cm3/g. A method for preparing the positive electrode is also provided.

Abstract: A positive electrode for a lithium secondary battery includes a collector; and a positive electrode active material layer disposed on at least one surface of the collector, wherein the ratio of a peak intensity of a (003) plane to a peak intensity of a (101) plane of the positive electrode measured by X-ray diffraction analysis is 8 or more.

Abstract: The present invention provides a method for preparing a graft copolymer for the application in a resin composition including a graft copolymer and a matrix resin, and relates to a method for preparing a graft copolymer maintaining impact properties such as impact strength and falling ball impact strength to the same or better levels, while improving flowability and subsequently improving processability, a graft copolymer prepared by the method and a resin composition including same.

Abstract: A bulk acoustic wave resonator includes a substrate, a first electrode, wherein a cavity is formed between the substrate and the first electrode, a piezoelectric layer disposed on the first electrode and overlapping at least a portion of the first electrode, a second electrode disposed on the piezoelectric layer and overlapping at least a portion of the piezoelectric layer, a passivation layer having at least a portion disposed on the second electrode and overlapping at least a portion of the second electrode, and a lower frame spaced apart from the substrate and having a portion of the cavity disposed therebetween. Any one of the second electrode and the passivation layer includes a protruding portion having a first thickness and an extended portion having a second thickness less than the first thickness, and an inner end of the lower frame and an end of the protruding portion are spaced apart horizontally.

Abstract: Disclosed is a method of preparing a vinyl cyanide compound-conjugated diene rubber-aromatic vinyl compound graft copolymer and a method of preparing a thermoplastic resin composition including the same. Also disclosed is a conjugated diene rubber latex having an average particle diameter of 2,400 to 2,800 Å added to enlarged conjugated diene rubber latex obtained by enlarging conjugated diene rubber latex having an average particle diameter of 2,400 to 2,800 Å using a polymer coagulant to prepare bimodal conjugated diene rubber, and a vinyl cyanide compound-conjugated diene rubber-aromatic vinyl compound graft copolymer prepared by graft-polymerizing the bimodal conjugated diene rubber.

Abstract: Provided are a method of preparing a graft copolymer and a graft copolymer, the method including: batch-adding a first molecular weight controlling agent, a diene-based rubber polymer, an aromatic vinyl-based monomer, and a vinyl cyanide-based monomer to a reactor to initiate polymerization; and after the initiation of polymerization, continuously adding a second molecular weight controlling agent, an aromatic vinyl-based monomer, and a vinyl cyanide-based monomer to the reactor to perform polymerization, wherein the second molecular weight controlling agent includes an alkyl styrene-based dimer and a mercaptan-based compound in a weight ratio of 40.0:60.0 to 70.0:30.0, and a weight ratio of the first molecular weight controlling agent and the second molecular weight controlling agent is 5.0:95.0 to 25.0:75.0.

Abstract: An acoustic resonator comprises a substrate, a resonant portion disposed on the substrate and in which a first electrode, a piezoelectric layer, and a second electrode are stacked, a protective layer disposed on an upper portion of the resonant portion, and a hydrophobic layer formed on the protective layer, and the protective layer comprises a first protective layer stacked on the second electrode and a second protective layer stacked on the first protective layer, wherein a density of the second protective layer is higher than a density of the first protective layer.

Abstract: The present invention relates to a galvanometer scanner, and the galvanometer scanner includes a mirror mounting shaft having a portion inserted into a shaft insertion opening of a housing which includes the shaft insertion opening on one surface thereof and has contents contained therein; and a mirror mounted at the mirror mounting shaft and positioned inside the housing.

Abstract: The present invention relates to a thermoplastic resin. More particularly, the present invention relates to a thermoplastic resin that is a graft copolymer having a seed-shell structure and includes a bimodal seed including a large-diameter rubbery polymer having an average particle diameter of greater than 2,000 ? and 3,500 ? or less and a small-diameter rubbery polymer having an average particle diameter of 500 ? to 2,000 ?; and an aromatic vinyl-vinyl cyan shell, wherein the aromatic vinyl cyan compound is included in an amount of 5% by weight to 28% by weight based on a total weight of the aromatic vinyl-vinyl cyan shell. In accordance with the present invention, a thermoplastic resin having a composition capable of improving graft density, and a thermoplastic resin composition capable of increasing dispersion and having high gloss due to inclusion of the thermoplastic resin are provided.

Abstract: The present invention provides a method of preparing a graft copolymer, which comprises graft emulsion polymerization of a diene-based rubber polymer with an aromatic vinyl-based monomer and a vinyl cyanide-based monomer in the presence of an azo-based initiator having a solubility in water at 20° C. of 10 g/100 g or more and a 10-hour half-life decomposition temperature in water of 80° C. or less, wherein the graft emulsion polymerization is initiated at 45 to 55° C. According to the present invention, a method of preparing a graft copolymer, which allows polymerization to be performed at low temperatures and ensures excellent polymerization stability, can be provided.

Abstract: A bulk acoustic wave resonator includes a substrate, a first electrode, wherein a cavity is formed between the substrate and the first electrode, a piezoelectric layer disposed on the first electrode and overlapping at least a portion of the first electrode, a second electrode disposed on the piezoelectric layer and overlapping at least a portion of the piezoelectric layer, a passivation layer having at least a portion disposed on the second electrode and overlapping at least a portion of the second electrode, and a lower frame spaced apart from the substrate and having a portion of the cavity disposed therebetween. Any one of the second electrode and the passivation layer includes a protruding portion having a first thickness and an extended portion having a second thickness less than the first thickness, and an inner end of the lower frame and an end of the protruding portion are spaced apart horizontally.

Abstract: Provided are a method for preparing a conjugated diene-based polymer and a method for preparing a graft copolymer including the same. The method for preparing a conjugated diene-based polymer includes enlarging a first conjugated diene-based polymer in multiple stages to prepare a second conjugated diene-based polymer, wherein the multi-stage enlargement includes a primary enlargement stage and a secondary enlargement stage, and a weight ratio of acids added in the primary enlargement stage and the secondary enlargement stage is 70:30 to 90:10. A graft copolymer prepared by the above-described method can be used to form a thermoplastic resin molded article excellent in all of plating characteristics, mechanical properties, surface characteristics, colorability, and processability.

Abstract: An acoustic resonator package includes a substrate, an acoustic resonator disposed on the substrate, the acoustic resonator including a first hydrophobic layer, a cap configured to accommodate the acoustic resonator, a bonding portion configured to bond the substrate to the cap, and a second hydrophobic layer disposed on the substrate at a position between the acoustic resonator and the bonding portion.

Abstract: The present invention relates to a method for preparing a graft copolymer including polymerizing a conjugated diene-based monomer to prepare a small-size conjugated diene-based polymer; enlarging the small-size conjugated diene-based polymer to prepare a large-size conjugated diene-based polymer; and polymerizing the small-size conjugated diene-based polymer, the large-size conjugated diene-based polymer, an aromatic vinyl-based monomer and a vinyl cyan-based monomer to prepare a graft copolymer, wherein a weight ratio of the small-size conjugated diene-based polymer and the large-size conjugated diene-based polymer is 10:90 to 40:60 in preparing the graft copolymer.

Abstract: The present invention relates to a galvanometer scanner, and the galvanometer scanner includes a mirror mounting shaft having a portion inserted into a shaft insertion opening of a housing which includes the shaft insertion opening on one surface thereof and has contents contained therein; and a mirror mounted at the mirror mounting shaft and positioned inside the housing.

Abstract: The present invention relates to a method for preparing a graft copolymer, which includes polymerizing a first conjugated diene-based polymer, a second conjugated diene-based polymer, an aromatic vinyl-based monomer and a vinyl cyan-based monomer, wherein particle size distribution of the first conjugated diene-based polymer is 0.346 to 0.404, and particle size distribution of the second conjugated diene-based polymer is 0.196 to 0.304, a graft copolymer and a thermoplastic resin molded article.

Abstract: The present invention relates to a method of preparing a thermoplastic resin, a method of preparing a thermoplastic resin composition including the same, and a method of manufacturing an injection-molded article using the thermoplastic resin composition. By using a mixture of molecular weight modifiers having different reactivities according to the present invention, coagulation may be performed using a small amount of coagulant, productivity may be increased, and a molded article, which is manufactured using a thermoplastic resin, having excellent appearance characteristics along with superior mechanical strength, processability, or the like may be provided.

Abstract: The present invention relates to a thermoplastic resin. More particularly, the present invention relates to a thermoplastic resin that is a graft copolymer having a seed-shell structure and includes a bimodal seed including a large-diameter rubbery polymer having an average particle diameter of greater than 2,000 ? and 3,500 ? or less and a small-diameter rubbery polymer having an average particle diameter of 500 ? to 2,000 ?; and an aromatic vinyl-vinyl cyan shell, wherein the aromatic vinyl cyan compound is included in an amount of 5% by weight to 28% by weight based on a total weight of the aromatic vinyl-vinyl cyan shell. In accordance with the present invention, a thermoplastic resin having a composition capable of improving graft density, and a thermoplastic resin composition capable of increasing dispersion and having high gloss due to inclusion of the thermoplastic resin are provided.

Abstract: The present invention relates to an ultrasonic nonlinearity measuring method generated by a high voltage pulser and more specifically, includes a calibration step of transmitting and receiving an ultrasonic signal to and from an object to be inspected having a reception probe attached thereto, by a receiving unit; a harmonic wave measuring step of transmitting a tone burst signal to an object to be inspected having a transmission/reception probe attached thereto and receiving the tone burst signal which passes through the object to be inspected, by the receiving unit; a harmonic wave measuring step of transmitting a tone burst signal to an object to be inspected having a transmission probe attached thereto and receiving the transmitted tone burst signal, by a transmitting unit; a calibration step of transmitting and receiving an ultrasonic signal to and from an object to be inspected having a transmission probe attached thereto, by the transmitting unit; and a step of measuring an ultrasonic nonlinearity of t

Abstract: The present invention relates to a method for preparing a graft copolymer including polymerizing a conjugated diene-based monomer to prepare a small-size conjugated diene-based polymer; enlarging the small-size conjugated diene-based polymer to prepare a large-size conjugated diene-based polymer; and polymerizing the small-size conjugated diene-based polymer, the large-size conjugated diene-based polymer, an aromatic vinyl-based monomer and a vinyl cyan-based monomer to prepare a graft copolymer, wherein a weight ratio of the small-size conjugated diene-based polymer and the large-size conjugated diene-based polymer is 10:90 to 40:60 in preparing the graft copolymer.