Abstract: A method for preparing a spheronized carbonaceous negative electrode active material, including the steps of: mixing microgranular scaly graphite with macrogranular scaly graphite, wherein the macrogranular scaly graphite has a larger average particle diameter than the microgranular scaly graphite, to form a mixture, and spheronizing the mixture to prepare spheronized granulated particles; carrying out carbon coating of the spheronized granulated particles; and disintegrating the carbon-coated spheronized granulated particles.

Abstract: A method for preparing a spheronized carbonaceous negative electrode active material, including the steps of: mixing scaly graphite, solid pitch and liquid pitch to form a mixture, and spheronizing the mixture to prepare spheronized granulated particles; firing the spheronized granulated particles; carrying out carbon coating of the fired spheronized granulated particles to form carbon-coated spheronized granulated particles; heat treating the carbon-coated spheronized granulated particles; and disintegrating the heat treated carbon-coated spheronized granulated particles.

Abstract: A negative electrode active material which includes a silicon-based composite represented by SiOa (0?a<1), and a carbon coating layer distributed on a surface of the silicon-based composite, and which has a bimodal pore structure including nanopores and mesopores. In a lithium secondary battery including the negative electrode active material, an oxygen content in the silicon-based composite can be controlled to improve initial efficiency and capacity characteristics, and a specific surface area can also be controlled, and thus a side reaction with electrolyte can be reduced.

Abstract: A negative electrode active material particle and a method for preparing the same are provided. The negative electrode active material particle includes SiOx (0<x?2) and Li2Si2O5, and includes less than 2 wt % of Li2SiO3 and Li4SiO4.

Abstract: The present invention relates to a superdirective speaker, and particularly, to a superdirective speaker in which speaker units are disposed and aligned adjacent to one another, and sound outputted from the speaker units overlaps and propagates stepwise, such that the sound may be clearly transmitted over a long distance.

Abstract: A semiconductor device include a nonvolatile memory device, including a first well region formed in a substrate, a tunneling gate insulator formed on the first well region, a floating gate formed on the tunneling gate insulator, a control gate insulator formed on the substrate, a control gate formed on the control gate insulator, and a first source region and a first drain region formed on opposite sides of the control gate, respectively, and a first logic device, including a first logic well region formed in the substrate, a first logic gate insulator formed on the first logic well region, a first logic gate formed on the first logic gate insulator, wherein the first logic gate comprises substantially a same material as a material of the control gate of the nonvolatile memory device.

Abstract: A semiconductor device include a nonvolatile memory device, including a first well region formed in a substrate, a tunneling gate insulator formed on the first well region, a floating gate formed on the tunneling gate insulator, a control gate insulator formed on the substrate, a control gate formed on the control gate insulator, and a first source region and a first drain region formed on opposite sides of the control gate, respectively, and a first logic device, including a first logic well region formed in the substrate, a first logic gate insulator formed on the first logic well region, a first logic gate formed on the first logic gate insulator, wherein the first logic gate comprises substantially a same material as a material of the control gate of the nonvolatile memory device.

Abstract: A method for preparing a negative electrode active material. The method includes disposing a pitch on graphite particles and performing a first heat treatment on the graphite particles to form a first carbon coating layer, and disposing a liquid resin on the first carbon coating layer and performing a second heat treatment on the graphite particles to form a second carbon coating layer.

Abstract: A hydrogel includes: a partially or fully ionized cationic polymer and at least one selected from the group consisting of a partially or fully ionized anionic polymer and a low molecular weight compound having two or more anionic groups; or a partially or fully ionized anionic polymer and at least one selected from the group consisting of a partially or fully ionized cationic polymer and a low molecular weight compound having two or more cationic groups; and water. The hydrogel can be used for for producing clay with viscoelastic properties.

Abstract: Provided is an active material for negative electrode including porous silicon-based particles and carbon particles, wherein the carbon particles include fine carbon particles and coarse carbon particles respectively having different average particle diameters. Since an active material for negative electrode according to an embodiment of the present invention includes porous silicon-based particles as well as fine and coarse carbon particles respectively having different average particle diameters, the contact between the porous silicon-based particles and the carbon particles may be increased. As a result, lifetime characteristics of a lithium secondary battery may be further improved.

Abstract: The present specification relates to a negative electrode active material including an amorphous silicon-based composite represented by SiOa (0<a<1); and a carbon coating layer distributed on a surface of the silicon-based composite, and provides a negative electrode active material in which the crystal growth of crystalline silicon in a silicon-based composite prepared by thermal reduction with a metal reducing agent is suppressed in a state where a carbon coating layer is formed, and the ratio of silicon in the composite is high, and a method of preparing the same.

Abstract: The present specification relates to a negative electrode active material including an amorphous silicon-based composite represented by SiOa (0<a<1); and a carbon coating layer distributed on a surface of the silicon-based composite, and provides a negative electrode active material in which the crystal growth of crystalline silicon in a silicon-based composite prepared by thermal reduction with a metal reducing agent is suppressed in a state where a carbon coating layer is formed, and the ratio of silicon in the composite is high, and a method of preparing the same.

Abstract: The present invention provides an optical device including a spectral filter and an optical detection unit for detecting light passing through the spectral filter. A band-limited filter is provided on the path of light.

Abstract: The present invention relates to a superdirective speaker, and particularly, to a superdirective speaker in which speaker units are disposed and aligned adjacent to one another, and sound outputted from the speaker units overlaps and propagates stepwise, such that the sound may be clearly transmitted over a long distance.

Abstract: The present invention provides an optical device including a spectral filter and an optical detection unit for detecting light passing through the spectral filter. A band-limited filter is provided on the path of light.

Abstract: A negative electrode active material particle and a method for preparing the same are provided. The negative electrode active material particle includes SiOx (0<x?2) and Li2Si2O5, and includes less than 2 wt % of Li2SiO3 and Li4SiO4.

Abstract: A semiconductor device include a nonvolatile memory device, including a first well region formed in a substrate, a tunneling gate insulator formed on the first well region, a floating gate formed on the tunneling gate insulator, a control gate insulator formed on the substrate, a control gate formed on the control gate insulator, and a first source region and a first drain region formed on opposite sides of the control gate, respectively, and a first logic device, including a first logic well region formed in the substrate, a first logic gate insulator formed on the first logic well region, a first logic gate formed on the first logic gate insulator, wherein the first logic gate comprises substantially a same material as a material of the control gate of the nonvolatile memory device.

Abstract: A negative electrode active material particle and a method for preparing the same are provided. The negative electrode active material particle includes SiOx (0<x?2) and Li2Si2O5, and includes less than 2 wt % of Li2SiO3 and Li4SiO4.