Abstract: An angle determining circuit and method, and a folding screen terminal are provided. The circuit is applied to the folding screen terminal which includes a first and second screens rotatably connected through a rotary shaft, a resistance ring is fixedly provided outside the rotary shaft. The circuit includes: a first power supply; a first resistor, where one terminal of the first resistor is electrically connected to the first power supply; a first conductive element fixedly disposed at the first screen, where one terminal of the first conductive element is electrically connected to the other terminal of the first resistor, and the other terminal thereof slidably abuts against the resistance ring; a second conductive element fixedly disposed at the second screen, where one terminal of the second conductive element slidably abuts against the resistance ring, and the other terminal thereof is grounded; and a processor.

Abstract: An angle determining circuit and method, and a folding screen terminal are provided. The circuit is applied to the folding screen terminal which includes a first and second screens rotatably connected through a rotary shaft, a resistance ring is fixedly provided outside the rotary shaft. The circuit includes: a first power supply; a first resistor, where one terminal of the first resistor is electrically connected to the first power supply; a first conductive element fixedly disposed at the first screen, where one terminal of the first conductive element is electrically connected to the other terminal of the first resistor, and the other terminal thereof slidably abuts against the resistance ring; a second conductive element fixedly disposed at the second screen, where one terminal of the second conductive element slidably abuts against the resistance ring, and the other terminal thereof is grounded; and a processor.

Abstract: The compound of this invention is a useful catalyst for the oxidative coupling of naphthol. Its originality lies in that it is a novel vanadium complex of Schiff's base formed by a chiral amino acid and a formyl biphenol or its derivative. Its axis chirality is induced to form by the chiral amino acid. It has the general formula: where R represents a benzyl, an isopropyl, an isobutyl or a tertiary butyl and the configuration of the amino acid is R or S. The compound can catalyze oxidative coupling of naphthol or its derivative to form binaphthol or its derivatives with a high optical purity.

Abstract: The compound of this invention is a useful catalyst for the oxidative coupling of naphthol. Its originality lies in that it is a novel vanadium complex of Schiff's base formed by a chiral amino acid and a formyl biphenol or its derivative. Its axis chirality is induced to form by the chiral amino acid. It has the general formula: where R represents a benzyl, an isopropyl, an isobutyl or a tertiary butyl and the configuration of the amino acid is R or S. The compound can catalyze oxidative coupling of naphthol or its derivative to form binaphthol or its derivatives with a high optical purity.