Abstract: Disclosed are a tweeter and an automobile audio system. The tweeter comprises: a bracket; a diaphragm comprising a top portion and an edge ring; a magnetic motor system; and a voice coil. A first cavity is formed between the top portion of the diaphragm, an inner wall of the voice coil, and the magnetic motor system. The bracket has an annular inner flange and an annular outer flange, the edge ring of the diaphragm is connected to the outer flange of the bracket, and the magnetic motor system is connected to the inner flange of the bracket, so that a second cavity is formed between the edge ring of the diaphragm, an outer wall of the voice coil, and the bracket. A through hole is opened on the voice coil, and the first cavity is in communication with the second cavity by the through hole.

Abstract: The present invention provides a huperzine B crystal and a preparation thereof. Specifically, the present invention provides a crystal form A of the huperzine B crystal. An X-ray diffraction pattern of the crystal form A has the following 2? angular characteristic absorption peak: 9.56±0.2, 13.90±0.2, 14.88±0.2, 16.00±0.2, 25.39±0.2, and 28.78±0.2.

Abstract: The present disclosure relates to a magnetic circuit of a loudspeaker and a loudspeaker, which can improve the non-linearity of magnetic permeability, thereby reducing the distortion of the loudspeaker. A magnetic circuit comprises a T-yoke with a base and a columnar portion protruding upward from the base, a magnetic steel arranged on the base, and a front sheet arranged on the magnetic steel, wherein the magnetic steel and the front sheet are arranged around a periphery of the columnar portion, and a short-circuit ring is arranged on an inner side of the magnetic steel and/or the front sheet. A first short-circuit ring is provided between the inner wall of the magnetic steel and the outer wall of the columnar portion, and a second short-circuit ring is provided on the inner wall of the front sheet.

Abstract: A mid-range loudspeaker, including a frame, a diaphragm arranged on the frame, a magnetic circuit system arranged on the frame, and a voice coil connected to the diaphragm. The diaphragm includes a honeycomb plate having a front surface and a back surface. Covering films respectively cover the front surface and the back surface of the honeycomb plate. The honeycomb plate is provided with a plurality of holes.

Abstract: Provided is a new method for activating transcription of a gamma-globin gene. The method uses a single-stranded oligonucleotide (ssODN) containing GATA or an antisense complementary sequence TATC thereof as guidance information, and performs gene editing in a gamma-globin gene promoter region to form a GATA-containing enhancer element, which can promote the expression of the gamma-globin gene in mature red blood cells. Hematopoietic stem cells genetically edited by the method have normal functions, can significantly improve the expression of fetal hemoglobin after being differentiated into red blood cells, and therefore can be used in clinical treatment of beta-thalassemia and sickle cell anemia.

Abstract: Provided are gRNA that can direct a Cas enzyme to target a CTGF gene and the use thereof, which belongs to the technical field of gene editing. The gRNA may direct the Cas enzyme to perform targeted cleavage on an SMAD binding site region of a CTGF gene promoter, or the gRNA may direct the Cas enzyme to perform targeted cleavage on a CTGF gene exon 2 region. The gRNA can reduce the overexpression of the human CTGF gene via a CRISPR-Cas gene editing system. The above-mentioned gRNA is used for preparing a drug for use against fibrotic diseases.

Abstract: Disclosed are a tweeter and an automobile audio system. The tweeter comprises: a bracket; a diaphragm comprising a top portion and an edge ring; a magnetic motor system; and a voice coil. A first cavity is formed between the top portion of the diaphragm, an inner wall of the voice coil, and the magnetic motor system. The bracket has an annular inner flange and an annular outer flange, the edge ring of the diaphragm is connected to the outer flange of the bracket, and the magnetic motor system is connected to the inner flange of the bracket, so that a second cavity is formed between the edge ring of the diaphragm, an outer wall of the voice coil, and the bracket. A through hole is opened on the voice coil, and the first cavity is in communication with the second cavity by the through hole.

Abstract: The present disclosure relates to a magnetic circuit of a loudspeaker and a loudspeaker, which can improve the non-linearity of magnetic permeability, thereby reducing the distortion of the loudspeaker. A magnetic circuit comprises a T-yoke with a base and a columnar portion protruding upward from the base, a magnetic steel arranged on the base, and a front sheet arranged on the magnetic steel, wherein the magnetic steel and the front sheet are arranged around a periphery of the columnar portion, and a short-circuit ring is arranged on an inner side of the magnetic steel and/or the front sheet. A first short-circuit ring is provided between the inner wall of the magnetic steel and the outer wall of the columnar portion, and a second short-circuit ring is provided on the inner wall of the front sheet.

Abstract: Disclosed is a mid-range speaker. The operating range of the mid-range speaker can extend to 20 KHz, and the speaker has an improved high-frequency directivity. A mid-range speaker, comprising a basket, a diaphragm arranged on the basket, a magnetic circuit system arranged on the basket, and a voice coil connected to the diaphragm, wherein the diaphragm comprises a cellular board having a front face and a back face, and covering films respectively covering the front face and the back face of the cellular board; and the cellular board is provided with a plurality of holes.

Abstract: A laser system for processing conductive link structures includes a seed laser generating a seed laser beam. The seed laser is sliced by a modulator into a user configurable series of pulses and the pulses are optically amplified and applied to a conductive link structure. Preferably, the bandwidth of the seed laser is less than 1 nm with an IR center frequency, and the frequency of the laser light of the pulses is doubled or quadrupled prior to application to the conductive structure. Preferably, the pulses are about 1-18 nanosecond pulsewidth and are separated by 100-400 nanoseconds.

Abstract: A method and system for laser processing targets of different types on a workpiece are provided. The method includes setting a laser pulse width of one or more laser pulses to selectively provide one or more laser output pulses having one or more set pulse widths based on a first type of target to be processed. The method further includes setting a pulse shape of the one or more output pulses to selectively provide the one or more output pulses having the set pulse shape based on the types of targets to be processed. The method still further includes delivering the one or more output pulses having the one or more set pulse widths and the set pulse shape to at least one target of the first type. The method finally includes resetting the laser pulse width of one or more laser pulses to selectively provide one or more laser output pulses having one or more reset pulse widths based on a second type of target to be processed.

Abstract: A method, system and scan lens for use therein are provided for high-speed, laser-based, precise laser trimming at least one electrical element along a trim path. The method includes generating a pulsed laser output with a laser, the output having one or more laser pulses at a repetition rate. A fast rise/fall time, pulse-shaped q-switched laser or an ultra-fast laser may be used. Beam shaping optics may be used to generate a flat-top beam profile. Each laser pulse has a pulse energy, a laser wavelength within a range of laser wavelengths, and a pulse duration. The wavelength is short enough to produce desired short-wavelength benefits of small spot size, tight tolerance, high absorption and reduced or eliminated heat-affected zone (HAZ) along the trim path, but not so short so as to cause microcracking. In this way, resistance drift after the trimming process is reduced.

Abstract: Laser-based methods and systems for removing one or more target link structures of a circuit fabricated on a substrate includes generating a pulsed laser output at a predetermined wavelength less than an absorption edge of the substrate are provided. The laser output includes at least one pulse having a pulse duration in the range of about 10 picoseconds to less than 1 nanosecond, the pulse duration being within a thermal laser processing range. The method also includes delivering and focusing the laser output onto the target link structure. The focused laser output has sufficient power density at a location within the target link structure to reduce the reflectivity of the target link structure and efficiently couple the focused laser output into the target link structure to remove the target link structure without damaging the substrate.

Abstract: A laser system for processing conductive link structures includes a seed laser generating a seed laser beam. The seed laser is sliced by a modulator into a user configurable series of pulses and the pulses are optically amplified and applied to a conductive link structure. Preferably, the bandwidth of the seed laser is less than 1 nm with an IR center frequency, and the frequency of the laser light of the pulses is doubled or quadrupled prior to application to the conductive structure. Preferably, the pulses are about 1-18 nanosecond pulsewidth and are separated by 100-400 nanoseconds.

Abstract: A method is disclosed for on-the-fly processing at least one structure of a group of structures with a pulsed laser output, The method includes the steps of relatively positioning the group of structures and the pulsed laser output axis with non-constant velocity, and applying the pulsed laser output to the at least one structure of the group of structures during the step of relatively positioning the group of structures and the pulsed laser output axis with non-constant velocity.

Abstract: A laser system for processing conductive link structures includes a seed laser generating a seed laser beam. The seed laser is sliced by a modulator into a user configurable series of pulses and the pulses are optically amplified and applied to a conductive link structure. Preferably, the bandwidth of the seed laser is less than 1 nm with an IR center frequency, and the frequency of the laser light of the pulses is doubled or quadrupled prior to application to the conductive structure. Preferably, the pulses are about 1-18 second pulsewidth and are separated by 100-400 ns.

Abstract: A method is disclosed for on-the-fly processing at least one structure of a group of structures with a pulsed laser output. The method includes the steps of relatively positioning the group of structures and the pulsed laser output axis with non-constant velocity, and applying the pulsed laser output to the at least one structure of the group of structures during the step of relatively positioning the group of structures and the pulsed laser output axis with non-constant velocity.

Abstract: Laser-based methods and systems for removing one or more target link structures of a circuit fabricated on a substrate includes generating a pulsed laser output at a predetermined wavelength less than an absorption edge of the substrate are provided. The laser output includes at least one pulse having a pulse duration in the range of about 10 picoseconds to less than 1 nanosecond, the pulse duration being within a thermal laser processing range. The method also includes delivering and focusing the laser output onto the target link structure. The focused laser output has sufficient power density at a location within the target link structure to reduce the reflectivity of the target link structure and efficiently couple the focused laser output into the target link structure to remove the target link structure without damaging the substrate.

Abstract: Laser-based methods and systems for removing one or more target link structures of a circuit fabricated on a substrate includes generating a pulsed laser output at a predetermined wavelength less than an absorption edge of the substrate are provided. The laser output includes at least one pulse having a pulse duration in the range of about 10 picoseconds to less than 1 nanosecond, the pulse duration being within a thermal laser processing range. The method also includes delivering and focusing the laser output onto the target link structure. The focused laser output has sufficient power density at a location within the target link structure to reduce the reflectivity of the target link structure and efficiently couple the focused laser output into the target link structure to remove the target link structure without damaging the substrate.

Abstract: A method and system for laser processing targets of different types on a workpiece are provided. The method includes setting a laser pulse width of one or more laser pulses to selectively provide one or more laser output pulses having one or more set pulse widths based on a first type of target to be processed. The method further includes setting a pulse shape of the one or more output pulses to selectively provide the one or more output pulses having the set pulse shape based on the types of targets to be processed. The method still further includes delivering the one or more output pulses having the one or more set pulse widths and the set pulse shape to at least one target of the first type. The method finally includes resetting the laser pulse width of one or more laser pulses to selectively provide one or more laser output pulses having one or more reset pulse widths based on a second type of target to be processed.