摘要:
The present invention is related to a method of producing polycarbosilane by heating polydimethylsilane at low pressure within the range of 320˜450° C. using zeolite having the Si/Al or Si/B ratio of 1˜200 as catalyst. This invention uses a zeolite with the structure of ZSM-5, ZSM-11, ZSM-12, zeolite X and zeolite Y, which has the Si/Al or Si/B ratio of 1˜200, as catalyst. When polycarbosilane is produced using a specific zeolite as catalyst, Si/Al or Si/B ratio can be adjusted at any proportion, enabling acidity control of catalyst, and therefore the molecular weight of final products can be easily controlled and the product yield can be improved, compared to conventional solid acid catalysts.
摘要:
The present invention relates to a clutch for transmission power. The clutch for transmission power according to the present invention includes flywheel, clutch cover and clutch disk assembly positioning between the flywheel and the clutch cover; moreover, the clutch disk assembly includes a clutch facing having main body portion formed with a center hole in the middle thereof, and a contacting portion wherein one side thereof faces the friction pad at said flywheel side and the other side thereof faces the press plate of said clutch cover, and the portion facing each other between the friction pad and the press plate is made of carbon-carbon composition; a spline hub being overlapped with one side of the clutch facing wherein a spline groove is formed in the inner diameter thereof; and a connecting means for connecting the clutch facing with the spline hub. Furthermore, the clutch disk assembly and the method of manufacturing the friction substance for clutch according to the invention can improve assemblability and reduce weight by simplifying it as a single part without using shock absorbing apparatus such as coil spring or the like on clutch disk assembly. In addition, the power transmission of an engine can be improved, and also it has an effect that an automobile can start softly and slippery does not occur even at abrupt acceleration by providing with carbon-carbon composition or carbon-silicon carbide composition having excellent shock absorption function.
摘要:
The present invention relates to a clutch for transmission power. The clutch for transmission power according to the present invention includes flywheel, clutch cover and clutch disk assembly positioning between the flywheel and the clutch cover; moreover, the clutch disk assembly includes a clutch facing having main body portion formed with a center hole in the middle thereof, and a contacting portion wherein one side thereof faces the friction pad at said flywheel side and the other side thereof faces the press plate of said clutch cover, and the portion facing each other between the friction pad and the press plate is made of carbon-carbon composition; a spline hub being overlapped with one side of the clutch facing wherein a spline groove is formed in the inner diameter thereof; and a connecting means for connecting the clutch facing with the spline hub. Furthermore, the clutch disk assembly and the method of manufacturing the friction substance for clutch according to the invention can improve assemblability and reduce weight by simplifying it as a single part without using shock absorbing apparatus such as coil spring or the like on clutch disk assembly. In addition, the power transmission of an engine can be improved, and also it has an effect that an automobile can start softly and slippery does not occur even at abrupt acceleration by providing with carbon-carbon composition or carbon-silicon carbide composition having excellent shock absorption function.
摘要:
The present invention relates to a composition for external skin application having a skin-moisturizing effect, which comprises gallocatechin gallate as an active ingredient. More particularly, the composition for external skin application comprises gallocatechin gallate as an active ingredient to activate peroxisome proliferator activated receptor isoform alpha (PPAR-α), to stimulate expression of filaggrin and involucrin that are skin-moisturizing factors, and thus to provide excellent anti-drying and skin-moisturizing effects. More particularly, the composition for external skin application may further comprise theobromine and quercetin in addition to gallocatechin gallate to maximize such effects.
摘要:
The present invention relates to a method for preparing a catalyst which is used in a process of producing acrolein and acrylic acid by the reaction of oxygen-containing gas and propylene. According to the present invention, a sublimable material, such as urea (NH2CONH2), melamine (C3H6N6), ammonium oxalate (C2H8N2O4), methyl oxalate (C4H6O4) or naphthalene (C10H8), is added as a catalyst additive in the preparation of the catalyst. Using the catalyst prepared by the present invention, acrolein and acrylic can be produced at high yield.
摘要翻译:本发明涉及一种制备催化剂的方法,该催化剂用于通过含氧气体和丙烯的反应生产丙烯醛和丙烯酸的方法。 根据本发明,可升华的材料,例如脲(NH 2 CONH 2 H 2),三聚氰胺(C 3 H 6) 草酸铵(C 2 H 2 N 2 N 2 O 4) 草酸甲酯(C 4 H 6 O 4 O 4)或萘(C 10 H 2 O) 作为催化剂添加剂加入催化剂的制备中。 使用本发明制备的催化剂可以高产率生产丙烯醛和丙烯酸。
摘要:
A method for fabricating a semiconductor device is disclosed. The method prevents line contact defects and overhangs associated with a barrier metal layer. The method includes forming a PMD layer on a semiconductor substrate including a terminal for the semiconductor device and forming a first contact hole by removing the PMD layer positioned over the terminal of the semiconductor device. Ions are implanted in at least portions of the PMD layer corresponding to corners associated with the contact hole. The comers of the PMD layer are rounded by etching the portions of the PMD layer that correspond to the contact hole. A metal line is formed by depositing a metal layer on the PMD layer including the contact hole and selectively removing portions of the metal layer.
摘要:
A method of manufacturing a single crystalline gallium nitride (GaN) thick film grown by loading a base substrate in a hydride vapor phase epitaxy (HVPE) reactor, the method including: growing a first GaN film at a first temperature, in the surface kinetics-controlled regime, where a growth rate is determined by the reaction rate on a film surface; and growing a second GaN film on the first GaN film at a second temperature, in the mass transport-controlled regime, where the growth rate is determined by a material transport in the vapor phase, wherein a growth temperature of the second GaN film is higher than that of the first GaN film. According to the present invention, defects, bending, and cracks may be reduced and the crystalline GaN thick film of excellent crystal quality may be manufactured.
摘要:
A single crystalline a-plane nitride semiconductor wafer includes one to three orientation flats in a crystalline direction, wherein a-plane ({11-20} plane) is formed as a main plane. Since plane orientation can easily be recognized, accuracy can be improved when a semiconductor device is formed on the nitride semiconductor wafer.
摘要:
Disclosed are a Mo—Bi—Nb—Te based composite metal oxide; and a process for producing (meth)acrylic acid from at least one reaction material selected from the group consisting of propylene, propane, isobutylene, t-butyl alcohol and methyl-t-butyl ether, wherein the Mo—Bi—Nb—Te based composite metal oxide is used as a catalyst. Also, disclosed is a process for producing (meth)acrylic acid comprising a first step of producing (meth)acrolein as a main product from at least one reaction material selected from the group consisting of propylene, propane, isobutylene, t-butyl alcohol and methyl-t-butyl ether, and a second step of producing (meth)acrylic acid from the (meth)acrolein, wherein yield of (meth)acrylic acid in the product of the first step is 20 mole % or higher.
摘要:
Disclosed is a method for manufacturing a semiconductor device including a low-voltage MOS transistor and a high-voltage MOS transistor. The present method includes a low-voltage well implantation process on a semiconductor substrate to form a first well in a first region of the substrate and a second well in a second region of the substrate; forming first and second gate oxide layers and first and second gate electrodes in the first and second regions, respectively; forming a first photoresist pattern to expose the first region; forming a first LDD region in the first region exposed by the first photoresist pattern and the first gate electrode; removing the first photoresist pattern; forming a second photoresist pattern to expose the second region; forming a second LDD region in the second region exposed by the second photoresist pattern and the second gate electrode; performing a compensational implantation on the second region to adjust a well concentration for the high-voltage MOS transistor; and removing the second photoresist pattern.