Abstract: A single-phase permanent magnet synchronous motor and dust collector. The single-phase permanent magnet synchronous motor includes a plurality of stator teeth, the plurality of stator teeth include at least: a first-type and second-type stator tooth; the first-type and second-type stator teeth enclose an annular working cavity for accommodating a rotor part, where the size of a central angle corresponding to a first contour line of an end face of the first-type stator tooth facing the rotor part is different from the size of a central angle corresponding to a second contour line of an end face of the second-type stator tooth facing the rotor part. The motor has a significantly reduced cogging torque, a greatly reduced torque ripple, and an obviously increased motor output torque. The single-phase permanent magnet synchronous motor is small in size, light in weight, simple in structure, convenient for large-scale manufacture and low in manufacturing cost.

Abstract: The present invention discloses a picture book recognition method applied to an apparatus with a camera, comprising: acquiring an image of the picture book with the camera at a preset acquisition frequency; uploading the image to a server; receiving a first audio link corresponding to the image returned from the server and, if the image is an image of a cover of the picture book, receiving a picture book ID corresponding to the cover image; and connecting to a first audio stream in the server and playing the audio according to the first audio link. The present invention further provides a picture book recognition apparatus, system and electronic device. The picture book recognition method, apparatus, system and electronic device provided by the present invention solve the problem of high error rate in picture book recognition in the prior art.

Abstract: Disclosed is a process for the preparation of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol by hydrogenation of the corresponding 2,2,4,4-tetraalkylcyclobutane-1,3-dione in the vapor phase in the presence of a supported catalyst. The process is useful for the preparation of 2,2,4,4-tetramethylcyclobutane-1,3-diol from 2,2,4,4-tetramethylcyclobutane-1,3-dione. The process can produce a 2,2,4,4-tetraalkylcyclobutane-1,3-diol product having a cis:trans isomer ratio of 1:1 or greater.

Abstract: Disclosed is a process for the preparation of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol by hydrogenation of the corresponding 2,2,4,4-tetraalkylcyclobutane-1,3-dione in the vapor phase in the presence of a supported catalyst. The process is useful for the preparation of 2,2,4,4-tetramethylcyclobutane-1,3-diol from 2,2,4,4-tetramethylcyclobutane-1,3-dione. The process can produce a 2,2,4,4-tetraalkylcyclobutane-1,3-diol product having a cis:trans isomer ratio of 1:1 or greater.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems for the polymerization of an olefin containing a solid titanium catalyst component containing an inorganic titanium compound, a magnesium alcohol adduct made from an inorganic magnesium compound and an alcohol, and a porous support having at least one of a certain specific surface area, a certain pore volume, and a certain median particle size. The catalyst system may further contain an organoaluminum compound and optionally an organosilicon compound. Also disclosed are methods of making polyolefins.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems for the polymerization of an olefin containing a solid titanium catalyst component containing an inorganic titanium compound, a magnesium alcohol adduct made from an inorganic magnesium compound and an alcohol, and a porous support having at least one of a certain specific surface area, a certain pore volume, and a certain median particle size. The catalyst system may further contain an organoaluminum compound and optionally an organosilicon compound. Also disclosed are methods of making polyolefins.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems for the polymerization of an olefin containing a solid titanium catalyst component containing an inorganic titanium compound, a magnesium alcohol adduct made from an inorganic magnesium compound and an alcohol, and a porous support having at least one of a certain specific surface area, a certain pore volume, and a certain median particle size. The catalyst system may further contain an organoaluminum compound and optionally an organosilicon compound. Also disclosed are methods of making polyolefins.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems for the polymerization of an olefin containing a solid titanium catalyst component containing an inorganic titanium compound, a magnesium alcohol adduct made from an inorganic magnesium compound and an alcohol, and a porous support having at least one of a certain specific surface area, a certain pore volume, and a certain median particle size. The catalyst system may further contain an organoaluminum compound and optionally an organosilicon compound. Also disclosed are methods of making polyolefins.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of polyethylene containing a solid titanium catalyst component containing a titanium compound and a support made from a magnesium compound, an alkyl silicate, and a monoester. The catalyst system may further contain an organoaluminum compound. Also disclosed are methods of making various types of polyethylene involving polymerizing ethylene in the presence of hydrogen and a catalyst system containing a support made from a magnesium compound, an alkyl silicate and a monoester.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of an olefin containing a solid titanium catalyst component having a substantially spherical shape and containing an internal electron donor, a support made from a magnesium compound, an alcohol, an ether, a surfactant, and an alkyl silicate. The catalyst system may further contain an organoaluminum compound and an organosilicon compound. Also disclosed are methods of making an impact copolymer involving polymerizing an olefin to provide a polyolefin matrix and polymerizing a polyolefin rubber using a catalyst component containing a support made from a magnesium compound, an alcohol, an ether, a surfactant, and an alkyl silicate.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of polyethylene containing a solid titanium catalyst component containing a titanium compound and a support made from a magnesium compound, an alkyl silicate, and a monoester. The catalyst system may further contain an organoaluminum compound. Also disclosed are methods of making various types of polyethylene involving polymerizing ethylene in the presence of hydrogen and a catalyst system containing a support made from a magnesium compound, an alkyl silicate and a monoester.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of an olefin containing a solid titanium catalyst component having a substantially spherical shape and containing a titanium compound and a support made from a magnesium compound and an alkyl silicate. The catalyst system may further contain an organoaluminum compound and an organosilicon compound. Also disclosed are methods of making an impact copolymer involving polymerizing an olefin to provide a polyolefin matrix and polymerizing a polyolefin rubber using a solid titanium catalyst component containing a titanium compound and a support made from a magnesium compound and an alkyl silicate.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of an olefin containing a solid titanium catalyst component having a substantially spherical shape and containing an internal electron donor, a support made from a magnesium compound, an alcohol, an ether, a surfactant, and an alkyl silicate. The catalyst system may further contain an organoaluminum compound and an organosilicon compound. Also disclosed are methods of making an impact copolymer involving polymerizing an olefin to provide a polyolefin matrix and polymerizing a polyolefin rubber using a catalyst component containing a support made from a magnesium compound, an alcohol, an ether, a surfactant, and an alkyl silicate.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of an olefin containing a solid titanium catalyst component having a substantially spherical shape and containing a titanium compound and a support made from a magnesium compound and an alkyl silicate. The catalyst system may further contain an organoaluminum compound and an organosilicon compound. Also disclosed are methods of making an impact copolymer involving polymerizing an olefin to provide a polyolefin matrix and polymerizing a polyolefin rubber using a solid titanium catalyst component containing a titanium compound and a support made from a magnesium compound and an alkyl silicate.