Abstract: Disclosed is a method of preparing an optically pure (R)- or (S)-tetrahydrofuranyl ketone. By such a method, (R)- or (S)-2-tetrahydrofuran amide is converted to (R)- or (S)-2-tetrahydrofuran nitrile through dehydration in the presence of a dehydrating agent and an amine base. Then, thus prepared (R)- or (S)-2-tetrahydrofuran nitrile is nucelophilic addition-reacted with a nucleophile, followed by hydrolyzing, thereby produce (R)- or (S)-tetrahydrofuranyl ketone having high optical purity, while minimizing production of other by-products.

Abstract: A color image display device has an auxiliary means for compensating brightness simply and inexpensively by using an electron gun of a cathode ray tube. Brightness uniformity is improved in the image display device having a flat-type color cathode ray tube with a glass panel having a high wedge ratio and a low transmissibility. The color image display includes a panel housing a screen on an inner face thereof, a funnel engaged with the panel; an electron gun engaged with a neck portion of the funnel for emitting electron beams toward the screen, a deflection device for displaying an image by deflecting the electron beams emitted from the electron gun in horizontal and vertical directions with respect to the screen, and a cathode ray tube including a shadow mask aligned from the screen at a predetermined distance.

Abstract: A deflection yoke is provided for a CRT, which includes horizontal and vertical deflection coils that deflect electron beams emitted from an electron gun in a horizontal or vertical direction, a ferrite core that reduces a loss of magnetic force caused by the horizontal and vertical deflection coils thereby enhancing magnetic efficiency, and a holder that holds the horizontal deflection coils, the vertical deflection coils, and the ferrite core at required positions, and provides insulation between the horizontal deflection coils and the vertical deflection coils. The horizontal and/or vertical deflection coils have a substantially rectangular shape on a screen side, and the ferrite core is circular or elliptical. This reduces material costs and reduces convergence and distortion errors, because a dimensional distribution of an inside surface area of the ferrite core is reduced with respect to related art deflection yokes, and polishing of an inside surface becomes easier.

Abstract: It is an object of the invention to provide a color image display device having an auxiliary means for compensating brightness simply and inexpensively, by using an electron gun of a cathode ray tube.

Abstract: Disclosed is a color flat panel display comprising a rear glass, a rear electrode, a filament cathode for emitting electrons, a control electrode, a signal modulation electrode, a focus electrode, a horizontal deflection electrode, a vertical deflection electrode, a front glass on which a phosphor screen is formed, and a spacer for maintaining an interval between the electrodes, wherein the spacer is plate-shaped and has a space part through which electron beams pass at an inside of thereof.

Abstract: Disclosed is a method of preparing an optically pure (R)- or (S)-tetrahydrofuranyl ketone. By such a method, (R)- or (S)-2-tetrahydrofuran amide is converted to (R)- or (S)-2-tetrahydrofuran nitrile through dehydration in the presence of a dehydrating agent and an amine base. Then, thus prepared (R)- or (S)-2-tetrahydrofuran nitrile is nucelophilic addition-reacted with a nucleophile, followed by hydrolyzing, thereby produce (R)- or (S)-tetrahydrofuranyl ketone having high optical purity, while minimizing production of other by-products.

Abstract: In a deflection yoke for a braun tube deflecting an electron beam radiated from an electron gun to a screen and including a horizontal deflection coil, a vertical deflection coil and a ferrite core, the horizontal deflection coil is installed inside a funnel, the ferrite core is installed outside of the funnel, the vertical deflection coil is installed inside or outside of the funnel, accordingly the convergence and deflection sensitivity of an electron beam can be easily compensated, the deflection sensitivity of a braun tube can improve, and the degree of freedom in designing the deflection yoke and an electron gun related to enlarging a diameter of the electron gun can increase.

Abstract: A deflection yoke of Braun tube having a horizontal deflection coil for horizontally deflecting electron beams radiated from an electron gun, a vertical deflection coil for vertically deflecting the electron beams, and a holder inserted between the horizontal and the vertical deflection coils for mechanically fixing them and electrically insulating them, including: an auxiliary coil having a first deflection portion coil extendedly formed from a ‘3-o'clock’ position of a neck side to a ‘3-o'clock’ direction of a screen side on the basis of the lengthy direction of the deflection coil; a first flange coil extendedly formed for a predetermined length from a ‘3-o'clock’ position of the screen side to a ‘12-o'clock’ direction of the screen side; a second deflection portion coil extendedly formed for a predetermined length from a ‘12-o'clock’ position of the screen side to a ‘12-o'clock’ direction of the neck side

Abstract: A deflection yoke is provided for a CRT, which includes horizontal and vertical deflection coils that deflect electron beams emitted from an electron gun in a horizontal or vertical direction, a ferrite core that reduces a loss of magnetic force caused by the horizontal and vertical deflection coils thereby enhancing magnetic efficiency, and a holder that holds the horizontal deflection coils, the vertical deflection coils, and the ferrite core at required positions, and provides insulation between the horizontal deflection coils and the vertical deflection coils. The horizontal and/or vertical deflection coils have a substantially rectangular shape on a screen side, and the ferrite core is circular or elliptical. This reduces material costs and reduces convergence and distortion errors, because a dimensional distribution of an inside surface area of the ferrite core is reduced with respect to related art deflection yokes, and polishing of an inside surface becomes easier.

Abstract: Disclosed is a method for optically resolving a racemic &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) by taking advantage of enantioselectivity of enzymes. &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then reacted with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. The extracted enantiomeric &agr;-HCCA ester is converted to enantiomeric &agr;-HCCA by catalytic hydrogenation in an organic solution or by enzymatic hydrolysis in an aqueous solution. Thus, a racemic mixture of &agr;-HCCA can be optically resolved with high optical purity at high yields as well as at low cost.

Abstract: Disclosed is a method for preparing an R- or S-forms of &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) and a counter enantiomeric form of &agr;-substituted heterocyclic carboxylic acid ester thereto by use of an enzyme. A racemic &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then brought into contact with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. Thus, a certain enantiomeric form of &agr;-HCCA and a counter enantiomeric form of &agr;-HCCA ester thereto, respectively can be prepared with high optical purity at high yields as well as at low cost.

Abstract: In a deflection yoke for a braun tube deflecting an electron beam radiated from an electron gun to a screen and including a horizontal deflection coil, a vertical deflection coil and a ferrite core, the horizontal deflection coil is installed inside a funnel, the ferrite core is installed outside of the funnel, the vertical deflection coil is installed inside or outside of the funnel, accordingly the convergence and deflection sensitivity of an electron beam can be easily compensated, the deflection sensitivity of a braun tube can improve, and the degree of freedom in designing the deflection yoke and an electron gun related to enlarging a diameter of the electron gun can increase.

Abstract: Disclosed is a method for optically resolving a racemic &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) by taking advantage of enantioselectivity of enzymes. &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then reacted with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. The extracted enantiomeric &agr;-HCCA ester is converted to enantiomeric &agr;-HCCA by catalytic hydrogenation in an organic solution or by enzymatic hydrolysis in an aqueous solution. Thus, a racemic mixture of &agr;-HCCA can be optically resolved with high optical purity at high yields as well as at low cost.

Abstract: Disclosed is a method for preparing an R- or S-forms of &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) and a counter enantiomeric form of &agr;-substituted heterocyclic carboxylic acid ester thereto by use of an enzyme. A racemic &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then brought into contact with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. Thus, a certain enantiomeric form of &agr;-HCCA and a counter enantiomeric form of &agr;-HCCA ester thereto, respectively can be prepared with high optical purity at high yields as well as at low cost.

Abstract: A deflection yoke of Braun tube having a horizontal deflection coil for horizontally deflecting electron beams radiated from an electron gun, a vertical deflection coil for vertically deflecting the electron beams, and a holder inserted between the horizontal and the vertical deflection coils for mechanically fixing them and electrically insulating them, including: an auxiliary coil having a first deflection portion coil extendedly formed from a ‘3-o'clock’ position of a neck side to a ‘3-o'clock’ direction of a screen side on the basis of the lengthy direction of the deflection coil; a first flange coil extendedly formed for a predetermined length from a ‘3-o'clock’ position of the screen side to a ‘12-o'clock’ direction of the screen side; a second deflection portion coil extendedly formed for a predetermined length from a ‘12-o'clock’ position of the screen side to a ‘12-o'clock’ direction of the neck side; a second flange coil extende

Abstract: A device for simply and precisely fixing a deflection yoke to a Braun tube in such a manner that it does not permanently affix the yoke to the Braun tube but permits the location and fixing angle of the yoke with respect to the Braun tube be easily changed as required. The device includes a holder, coupled to a separator, and a plurality of wedge type cams rotatably mounted on the holder. The holder is provided with a plurality of mounts for rotatably supporting the wedge type cams respectively, a plurality of releasable fixing members for fixing the cams at their adjusted angles, and connection bands extending between the mounts for connecting the mounts together. The wedge type cams not only adjust the yoke fixing angle for compensation of mis-alignment of electron gun but also releasably affix the deflection yoke to the Braun tube. In another embodiment, the wedge type cams may be substituted by pulley type cams which are rotatably mounted on the holder.