Abstract: The present invention relates to a transition metal complex and a transition metal catalyst composition comprising the same for the preparation of an ethylene homopolymer or a copolymer of ethylene and ?-olefin. More particularly, it relates to a group IV transition metal catalyst having a cyclopentadiene derivative and at least one aryl oxide ligand in which an oxygen-containing heterocycle is fused at the ortho-position around a group IV transition metal, with no crosslinkage between the ligands, a catalyst composition comprising the transition metal catalyst and an aluminoxane cocatalyst or a boron compound cocatalyst, and a process for preparing an ethylene homopolymer or a copolymer of ethylene and ?-olefin using the same.

Abstract: The present invention relates to a transition metal complex and a transition metal catalyst composition comprising the same for the preparation of an ethylene homopolymer or a copolymer of ethylene and ?-olefin. More particularly, it relates to a group IV transition metal catalyst having a cyclopentadiene derivative and at least one aryl oxide ligand in which an oxygen-containing heterocycle is fused at the ortho-position around a group IV transition metal, with no crosslinkage between the ligands, a catalyst composition comprising the transition metal catalyst and an aluminoxane cocatalyst or a boron compound cocatalyst, and a process for preparing an ethylene homopolymer or a copolymer of ethylene and ?-olefin using the same.

Abstract: Disclosed are a transition metal complex having a high catalytic activity for the preparation of an ethylene homopolymer or a copolymer of ethylene and ?-olefin and a catalyst composition comprising the same. More specifically, there are provided a transition metal complex having, around a group IV transition metal, a cyclopentadiene derivative and at least one aryl oxide ligand with a heterocyclic aryl derivative substituted at the ortho-position thereof, with no crosslinkage between the ligands, a catalyst composition comprising the transition metal complex and an organoaluminum compound or boron compound as cocatalyst, and a method for the preparation of high molecular weight ethylene homopolymers or copolymers of ethylene and ?-olefin using the same.

Abstract: There is provided a process for preparing a glycidyl derivative from 3-chloro-1,2-propanediol, comprising i) adding a phosphate salt to a solution into which 3-chloro-1,2-propanediol is dissolved into a solvent to produce glycidol, and ii) adding to the solution of step i) a base capable of releasing a glycidyl group from the glycidol and a substrate susceptible to nucleophilic attack to produce the desired glycidyl derivative by nucleophilic attack of the glycidyl group to the substrate.

Abstract: Disclosed relates to a process for preparing N(5)-ethylglutamines economically without a specific purification process via a simplified and safe process, in which glutamic acid derivatives, represented by formula 1, protected by phthaloyl groups react with ethylamine to cause an amidation and a deprotection reaction in turn under the same reaction condition, thus preparing N(5)-ethylglutamines.

Abstract: There is provided a process for preparing a glycidyl derivative from 3-chloro-1,2-propanediol, comprising i) adding a phosphate salt to a solution into which 3-chloro-1,2-propanediol is dissolved into a solvent to produce glycidol, and ii) adding to the solution of step i) a base capable of releasing a glycidyl group from the glycidol and a substrate susceptible to nucleophilic attack to produce the desired glycidyl derivative by nucleophilic attack of the glycidyl group to the substrate.

Abstract: The present invention relates to a method for the preparation of 3-substituted-3?-hydroxypropionitrile, more particularly, to a method for the preparation of 3-substituted-3?-hydroxypropionitrile which comprises performing ring opening of 1-substituted-ethylene oxide using sodium cyanide and citric acid in a range of pH 7.8˜8.3 to provide 3-substituted-3?-hydroxypropionitrile in high optical purity and with high yield.

Abstract: The present invention relates to chiral salen catalysts and a process for preparing chiral compounds from racemic epoxides by using them. More particularly, the present invention is to provide a chiral polymeric salen catalyst and its use for producing chiral compounds such as chiral epoxides and chiral 1,2-diols economically in high yield and high optical purity by performing stereoselective hydrolysis or racemic epoxides.

Abstract: The present invention relates to new chiral salen catalysts and methods for the preparation of chiral compounds from racemic epoxides by using new catalyst. More particularly, the present invention is to provide novel chiral salen catalysts and their uses for producing chiral compounds having high optical purity to be used as raw materials for preparing chiral medicines or food additives in a large scale economically, wherein the chirl salen catalyst having a particular molecules structure can be reused continuously without any activating process of used catalysts and cause no or little racemization after the reaction is completed because it maintains its catalytic activity after the reaction process.

Abstract: A digital zoom-out processing apparatus for accomplishing a digital zoom-out function by synthesizing a plurality of field or frame image information using motion information, is provided. The apparatus includes an image signal storage unit, a motion information detector, and a record and control unit. The image signal storage unit stores a plurality of frames or field image signals. The motion information detector detects the motion information between two image signals. The record and control unit zooms out received frame or field image signals in accordance with the given magnification and recording zoomed-out image signals in the image signal storage unit, and controls the location in the image signal storage at which the zoomed-out image signals are to be recorded. The digital zoom-out apparatus accomplishes a digital zoom-out function which enables processing of a large image in units of one screen.

Abstract: The present invention relates to a process for preparing (−)-(18-crown-6)-2,3,11,12-tetracarboxylic acid and its use for (−)-chiral stationary phases for resolution of racemic compounds. More particularly, the present invention relates to the process for preparing (−)-(18-crown-6)-2,3,11,12-tetracarboxylic acid expressed by formula (1) and the use thereof as a stationary phases for resolution of racemic compounds, wherein the use of them provides excellent separation of a desired chiral compound from racemic mixture in employing capillary electrophoresis (CE) or liquid chromatography to elute the desired one first by controlling a flowing order of enantioners, thus allowing to be consistently separated in an economical due to much less requirement of eluent, quantitative and high purity manner.

Abstract: The present invention relates to chiral salen catalysts and a process for preparing chiral compounds from racemic epoxides by using them. More particularly, the present invention is to provide chiral salen catalysts and its use for producing chiral compounds such as chiral epoxides and chiral 1,2-diols economically in high yield and high optical purity by performing stereoselective hydrolysis of racemic epoxides, wherein the chiral salen catalyst comprises a cationic cobalt as a center metal of chiral salen ligand and counterions having weak nucleophilic property to resolve disadvantages associated with conventional chiral salen catalysts, and can be used continuously without any activating process of used catalysts because it does not loose a catalytic activity during the reaction process.

Abstract: The present invention relates to chiral salen catalysts and a process for preparing chiral compounds from racemic epoxides by using them. More particularly, the present invention is to provide a chiral polymeric salen catalyst and its use for producing chiral compounds such as chiral epoxides and chiral 1,2-diols economically in high yield and high optical purity by performing stereoselective hydrolysis or racemic epoxides.

Abstract: The present invention relates to a process for preparing (−)-(18-crown-6)-2,3,11,12-tetracarboxylic acid and its use for (−)-chiral stationary phases for resolution of racemic compounds. More particularly, the present invention relates to the process for preparing (−)-(18-crown-6)-2,3,11,12-tetracarboxylic acid expressed by formula (1) and the use thereof as a stationary phases for resolution of racemic compounds, wherein the use of them provides excellent separation of a desired chiral compound from racemic mixture in employing capillary electrophoresis (CE) or liquid chromatography to elute the desired one first by controlling a flowing order of enantioners, thus allowing to be consistently separated in an economical due to much less requirement of eluent, quantitative and high purity manner.

Abstract: The present invention relates to new chiral salen catalysts and methods for the preparation of chiral compounds from racemic epoxides by using new catalyst. More particularly, the present invention is to provide novel chiral salen catalysts and their uses for producing chiral compounds having high optical purity to be used as raw materials for preparing chiral medicines or food additives in a large scale economically, wherein the chirl salen catalyst having a particular molecules structure can be reused continuously without any activating process of used catalysts and cause no or little racemization after the reaction is completed because it maintains its catalytic activity after the reaction process.

Abstract: An apparatus for maintaining the average light level of a screen for a ferroelectric liquid crystal display (LCD) is provided. The apparatus for maintaining the average light level of a screen for a ferroelectric liquid crystal display (LCD), includes an average light level detector for detecting the average light level of an input signal, using a predetermined pixel value of the input signal, a system controller for providing a predetermined reference average light level, and a screen light adjuster for receiving a reference average light level provided by the average light level of the input signal output from the average light level detector and the reference average light level provided by the system controller, adjusting the light of a screen so that the difference between the average light level of the input signal and the reference average light level is reduced, and keeping the average light level of the screen uniform.

Abstract: The present invention relates to chiral salen catalysts and a process for preparing chiral compounds from racemic epoxides by using them. More particularly, the present invention is to provide chiral salen catalysts and its use for producing chiral compounds such as chiral epoxides and chiral 1,2-diols economically in high yield and high optical purity by performing stereoselective hydrolysis of racemic epoxides, wherein the chiral salen catalyst comprises a cationic cobalt as a center metal of chiral salen ligand and counterions having weak nucleophilic property to resolve disadvantages associated with conventional chiral salen catalysts, and can be used continuously without any activating process of used catalysts because it does not loose a catalytic activity during the reaction process.

Abstract: A chrominance signal processing apparatus in a video signal processing system which has a simple configuration capable of achieving chrominance signal control and RGB transform functions using a single circuit.

Abstract: Disclosed is a process for preparing optically active (−)pyridobenzoxazine carboxylic acid derivative and pharmaceutically acceptable salt thereof by employing a starting material of (+)ethyl 2-(4-chloro-5-fluoro-2-halo-3-nitobenzoyl)-3-[(1-hydroxypropy-2(s)-yl)amino]acrylate. According to the present invention, optically active (−)pyridobenzoxazine carboxylic acid derivative can be manufactured from low-priced 4-chloro-5-fluorobenzoic acid derivative in a simple and economical manner.

Abstract: The present invention provides a method of preparing ortho-difluorobenzene derivatives, which comprises (a) providing a mixture of cyclohexenes by reacting chlorotrifluoroethylene (CTFE) and 1.3-diene in a flow reactor and distilling the resultant, and (b) dehydrohalogenating the mixture of cyclohexenes with a phase transition catalyst in :he presence of alkali metal hydroxide at temperature range of 40 to 150.degree. C. without using any organic solvent. The distillate having low boiling point, which is obtained during distillation of the resultant, is recycled into the flow reactor. The present invention also provides a method of preparing 2-chloro-4,5-difluorobenzoic acid, which comprises (a) providing a mixture of 4-chloro-1-methyl-4,5,5-trifluorocyclohexene and 5-chloro-1-methyl-4,4,5-trifluorocyclohexene by reacting chlorotrifluoroethylene (CTFE) and isoprene and distilling the resultant.