Abstract: A semiconductor memory device includes a memory cell array, a row decoder, a plurality of page buffers, and a voltage switching circuit. The memory cell array includes a plurality of memory cells. The row decoder is connected to the memory cell array through word lines. The plurality of page buffers are connected to the memory cell array through bit lines. The voltage switching circuit decodes an operation voltage and transmits the decoded operation voltage to the row decoder. The plurality of page buffers are formed in a first under cell region among first and second under cell regions, the first and second under cell regions being adjacent to each other in a first direction under the memory cell array. At least a portion of the voltage switching circuit is formed in an under slim region that is adjacent to the first under cell region and the second under cell region in a second direction.

Abstract: An automated driving system of a vehicle includes a driver monitoring unit configured to perform at least one of monitoring a gaze of a driver and determining a position of a hand of the driver, an automated-driving-level switching unit configured to determine whether a transition of a driving control over the vehicle is required based on whether driving environment of the vehicle has changed during the vehicle being driven under control of the automated driving system, and determine an automated driving level to be switched based on a driver monitoring result obtained by the drive monitoring unit, and an automated driving control unit configured to control the vehicle according to the automated driving level.

Abstract: A composition including a plurality of quantum dots; a binder polymer; a thiol compound having at least two thiol groups; a polyvalent metal compound; a polymerizable monomer having a carbon-carbon double bond; a photoinitiator; and a solvent.

Abstract: A positive electrode active material for a lithium secondary battery has a mixture of microparticles having a predetermined average particle size (D50) and macroparticles having a larger average particle size (D50) than the microparticles. The microparticles have the average particle size (D50) of 1 to 10 ?m and are at least one selected from the group consisting of particles having a carbon material coating layer on all or part of a surface of primary macroparticles having an average particle size (D50) of 1 ?m or more, particles having a carbon material coating layer on all or part of a surface of secondary particles formed by agglomeration of the primary macroparticles, and a mixture thereof. The macroparticles are secondary particles having an average particle size (D50) of 5 to 20 ?m formed by agglomeration of primary microparticles having a smaller average particle size (D50) than the primary macroparticles.

Abstract: An atomic layer etching method using a ligand exchange reaction may include a substrate providing step of putting a substrate with a thin film formed thereon into a reaction chamber, a halogenated thin film forming step of forming a halogenated thin film on a surface of the thin film by infusing a halogenated gas into the reaction chamber, and an etching step of etching the halogenated thin film by infusing a ligand without a metal or metal precursor into the reaction chamber with the substrate with the halogenated thin film.

Abstract: Disclosed is a dental orthodontic sheet having a composite structure in which different materials are stacked and bound to each other. The composite structure dental orthodontic sheet includes a first sheet layer, a second sheet layer, and an intermediate sheet layer formed between the first sheet layer and the second sheet layer, wherein the intermediate sheet layer includes a mat portion made of a softer material than each of the first sheet layer and the second sheet layer, the mat portion being formed so as to have a mesh structure, and a binding portion configured to allow mesh holes of the mat portion to be filled with materials of the first sheet layer and the second sheet layer such that the first sheet layer and the second sheet layer are bound to each other.

Abstract: The present invention relates to a propylene polymerizing solid catalyst for reducing the volatile organic compound (VOC) and a method of producing polypropylene using the propylene polymerizing solid catalyst, the propylene polymerizing solid catalyst including an organic electron donor formed of a combination of a first internal electron donor of titanium, magnesium, halogen and cyclic diester and a second internal electron donor of diether, and has improved hydrogen reactivity of a catalyst compared to a conventional method and has an effect that is capable of producing an eco-friendly polypropylene which has greatly lowered a content of the VOC by using the catalyst.

Abstract: The present invention relates to a solid catalyst for propylene polymerization and a method of producing a propylene polymer or copolymer using the solid catalyst for propylene polymerization, and provides a solid catalyst which prepares a dialkoxymagnesium carrier and is formed of a carrier produced through a reaction of the carrier with a metal halide, a titanium halide, an organic electron donor, etc., and a method of producing a propylene polymer or copolymer through copolymerization of propylene-alpha olefin using the solid catalyst, wherein the dialkoxymagnesium carrier has an uniform particle size range of 10 to 100 ?m and a spherical particle shape by adjusting injection amounts, injection numbers, and reaction temperatures of metal magnesium, alcohol and a reaction initiator during a reaction process of metal magnesium and alcohol.

Abstract: Disclosed is a method for preparing a solid catalyst for propylene polymerization, and more specifically, a method for preparing a solid catalyst for propylene polymerization including (1) first reacting dialkoxy magnesium and titanium halide compound under the presence of an organic solvent; (2) adding two kinds of non-aromatic internal electron donors to a product of the step (1) and reacting the mixture; and (3) second reacting the product of the step (2) with a titanium halide compound and washing a reaction product. The catalyst prepared according to the method as described in the present disclosure not only may provide high catalytic activity, but also may provide a propylene polymer having excellent stereoregularity.

Abstract: Disclosed is a method for preparing a solid catalyst for propylene polymerization, and more specifically, a method for preparing a solid catalyst for propylene polymerization including (1) first reacting dialkoxy magnesium and titanium halide compound under the presence of an organic solvent; (2) adding two kinds of non-aromatic internal electron donors to a product of the step (1) and reacting the mixture; and (3) second reacting the product of the step (2) with a titanium halide compound and washing a reaction product. The catalyst prepared according to the method as described in the present disclosure not only may provide high catalytic activity, but also may provide a propylene polymer having excellent stereoregularity.

Abstract: The present disclosure relates to a solid catalyst for propylene polymerization and a process for manufacture of a propylene polymer or copolymer using the solid catalyst, and provides a solid catalyst including carriers produced via a reaction between dialkoxy magnesium and metal halide, titanium halide, an organic electron donor, etc. and a process of manufacture of a propylene-based block copolymer via copolymerization of propylene-?-olefin using the solid catalyst. Particularly, internal electron donors including an ester group and an alkoxy group are used as two kinds of organic electron donors used in the present disclosure, and, thus, a block copolymer having high activity and excellent stereoregularity and a high rubber content via copolymerization with ?-olefin can be produced using a solid catalyst system suggested in the present disclosure.

Abstract: The present invention relates to a solid catalyst for propylene polymerization and a method of producing a propylene polymer or copolymer using the solid catalyst for propylene polymerization, and provides a solid catalyst which prepares a dialkoxymagnesium carrier and is formed of a carrier produced through a reaction of the carrier with a metal halide, a titanium halide, an organic electron donor, etc., and a method of producing a propylene polymer or copolymer through copolymerization of propylene-alpha olefin using the solid catalyst, wherein the dialkoxymagnesium carrier has an uniform particle size range of 10 to 100 ?m and a spherical particle shape by adjusting injection amounts, injection numbers, and reaction temperatures of metal magnesium, alcohol and a reaction initiator during a reaction process of metal magnesium and alcohol.

Abstract: The present invention relates to a propylene polymerizing solid catalyst for reducing the volatile organic compound (VOC) and a method of producing polypropylene using the propylene polymerizing solid catalyst, the propylene polymerizing solid catalyst including an organic electron donor formed of a combination of a first internal electron donor of titanium, magnesium, halogen and cyclic diester and a second internal electron donor of diether, and has improved hydrogen reactivity of a catalyst compared to a conventional method and has an effect that is capable of producing an eco-friendly polypropylene which has greatly lowered a content of the VOC by using the catalyst.

Abstract: The present disclosure relates to a process for producing ethylene oligomers and more particularly, to a process for oligomerizing ethylene by recycling butene, hexene, and octene in an ethylene oligomerization reaction with a catalyst system including a transition metal or transition metal precursor, a ligand with a backbone structure expressed by the following Chemical Formula 1, and a co-catalyst. [Chemical Formula 1] R1—O—Y—O—R2 or R1—OC(?O)—Y—C(?O)OR2 Herein, R1, R2 are each independently hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, or substituted heterohydrocarbyl, and Y represents a group connecting O or C(?O)O and is hydrocarbyl, substituted hydrocarbyl, hetero hydrocarbyl, or substituted heterohydrocarbyl. According to the oligomerization method of the present disclosure, in the distribution of the produced ?-olefins, C10?-C12? ?-olefins care highly distributed, the produced ?-olefins have a remarkably high purity.

Abstract: The present disclosure relates to a process for producing ethylene oligomers and more particularly, to a process for oligomerizing ethylene by recycling butene, hexene, and octene in an ethylene oligomerization reaction with a catalyst system including a transition metal or transition metal precursor, a ligand with a backbone structure expressed by the following Chemical Formula 1, and a co-catalyst. [Chemical Formula 1] R1—O—Y—O—R2 or R1—OC(?O)—Y—C(?O)OR2 Herein, R1, R2 are each independently hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl, or substituted heterohydrocarbyl, and Y represents a group connecting O or C(?O)O and is hydrocarbyl, substituted hydrocarbyl, hetero hydrocarbyl, or substituted heterohydrocarbyl. According to the oligomerization method of the present disclosure, in the distribution of the produced ?-olefins, C10?-C12? ?-olefins care highly distributed, the produced ?-olefins have a remarkably high purity.

Abstract: The present disclosure relates to a solid catalyst for propylene polymerization and a process for manufacture of a propylene polymer or copolymer using the solid catalyst, and provides a solid catalyst including carriers produced via a reaction between dialkoxy magnesium and metal halide, titanium halide, an organic electron donor, etc. and a process of manufacture of a propylene-based block copolymer via copolymerization of propylene-?-olefin using the solid catalyst. Particularly, internal electron donors including an ester group and an alkoxy group are used as two kinds of organic electron donors used in the present disclosure, and, thus, a block copolymer having high activity and excellent stereoregularity and a high rubber content via copolymerization with ?-olefin can be produced using a solid catalyst system suggested in the present disclosure.

Abstract: Provided is a method of preparation of a spherical support for an olefin polymerization catalyst. Specifically, provided is a method of preparation of a support which can be used in preparation of an olefin polymerization catalyst, wherein, MgX(I) (X=halogen atom) is prepared by reacting a reaction initiator, nitrogen halide, and magnesium metal, and then magnesium metal and alcohol are reacted in the presence of the MgX, thereby resulting a smooth-surfaced spherical dialkoxy magnesium support having a uniform particle size distribution.

Abstract: Disclosed is a method for preparing a solid catalyst for propylene polymerization, specifically to a method for preparing a solid catalyst for propylene polymerization which can produce a polypropylene having high melt flow rate, a wide molecular distribution and excellent stereoregularity with a high production yield.

Abstract: Disclosed are a method for preparing a solid catalyst for propylene polymerization and a catalyst prepared thereby. Specifically, disclosed are a method for preparing a solid catalyst for propylene polymerization which can prepare polypropylene having excellent stereoregularity with a high production yield by using silane compounds and bicycloalkanedicarboxylate or bicycloalkenedicarboxylate as an internal electron donor, and a catalyst prepared thereby method for preparing polypropylene using the same.