Abstract: A metal organic framework glass membrane and a preparation method thereof are provided. The preparation method includes a step of heating a crystalline metal organic framework material to the melting temperature at a rate of 1-15° C./min and then naturally cooling the crystalline metal organic framework material. The crystalline metal organic framework material contains a metal node and a ligand A. The metal node is a zinc ion and/or a cobalt ion and the ligand A is imidazole or phosphoric acid. The metal organic framework glass membrane has a wide range of membrane-forming conditions, and the material thereof can be melted without being decomposed within a control range to form a continuous glass layer with good repeatability.

Abstract: The provided is a tidal flat extraction method based on hyperspectral data. The method includes: acquiring and preprocessing hyperspectral data; calculating a constraint condition; calculating, according to the constraint condition, a normalized difference tidal flat index (NDTFI), generating a sample index statistical box chart, and determining a tidal flat extraction threshold according to the sample index statistical box chart; and removing a misclassified pixel based on a coastal buffer zone and a high spatial resolution image, thereby achieving final extraction of a tidal flat. The method has the following beneficial effects. The method is an effective supplement to the existing tidal flat extraction methods. The method adopts an easily realized process, improves the accuracy of tidal flat extraction, reflects the real spatial distribution of the tidal flat, and provides a scientific basis for tidal flat management and protection.

Abstract: The present disclosure provides a method for preparing natural starch microspheres with a uniform particle size. The method includes the following steps: heating natural starch and water for gelatinization to form a water phase; controlling a temperature of a substance including a low-polarity solvent to form an oil phase; dispersing the water phase into the oil phase to obtain a mixed solution; treating the mixed solution under reduced pressure, and carrying out separation to obtain preliminarily solidified starch microspheres; and washing the preliminarily solidified starch microspheres to remove the residual oil phase on the surface, and drying to obtain the natural starch microspheres. Compared with the present technology, the method of the present disclosure can retain the molecular structure of the natural starch and has a high yield, and the prepared natural starch microspheres have a uniform particle size and can load water-soluble and fat-soluble loading objects.

Abstract: The provided is a tidal flat extraction method based on hyperspectral data. The method includes: acquiring and preprocessing hyperspectral data; calculating a constraint condition; calculating, according to the constraint condition, a normalized difference tidal flat index (NDTFI), generating a sample index statistical box chart, and determining a tidal flat extraction threshold according to the sample index statistical box chart; and removing a misclassified pixel based on a coastal buffer zone and a high spatial resolution image, thereby achieving final extraction of a tidal flat. The method has the following beneficial effects. The method is an effective supplement to the existing tidal flat extraction methods. The method adopts an easily realized process, improves the accuracy of tidal flat extraction, reflects the real spatial distribution of the tidal flat, and provides a scientific basis for tidal flat management and protection.

Abstract: Disclosed is a splitting spinning apparatus, including: a base, a turntable for supporting a blank, a rotating mechanism for driving the turntable, a mandrel disposed above the turntable, and a first drive mechanism for driving the mandrel to move along a vertical direction, a roller being provided at one side of the turntable, a second drive mechanism and a third drive mechanism being disposed on the base; the splitting spinning apparatus further includes a squeezing roll and a fourth drive mechanism; the turntable includes an inner plate, an outer plate, and a hold mechanism, the blank having a diameter greater than that of the inner plate and less than an outer diameter of the outer plate, an upper side of the inner plate being in flush with an upper side of the outer plate, an outer diameter of the squeezing roll being equal to the diameter of the inner plate.

Abstract: The invention relates to an electrostatic ion trap having a central axis and a central symmetrical plane perpendicular to the central axis. The electrostatic ion trap comprises an inner electrode group arranged along the central axis and a pair of outer electrode groups arranged on two sides of the central symmetry plane along the central axis. Each outer electrode group comprises a plurality of electrode plates. The plurality of electrode plates are circumferentially distributed around a periphery of the inner electrode group and centered on the central axis. At least two electrode plates in the same outer electrode group are electrically connected. A potential difference is formed when voltages are respectively applied to the inner electrode group and the outer electrode groups, thereby forming a space for trapping ions between the inner electrode group and the outer electrode groups.

Abstract: A mid-infrared gas sensor based on a tapered sub-wavelength grating slot waveguide comprises a lower cladding, a first tapered grating array and a second tapered grating array. The first tapered grating array and the second tapered grating array are disposed on an upper surface of the lower cladding. The first tapered grating array is located in front of the second tapered grating array. The first tapered grating array is formed by 5566 identical first core waveguides that are regularly distributed at intervals from left to right. The second tapered grating array is formed by 5566 identical second core waveguides that are regularly distributed at intervals from left to right. The first core waveguides and the second core waveguides are tapered waveguides. Upper sides and lower sides of the first core waveguides and the second core waveguides are isosceles trapezoids.

Abstract: A piezoelectric sensor is provided. The piezoelectric sensor comprises a first base, a first conductive layer adjacent to the first base, a second base, a second conductive layer adjacent to the second base; and a first structure between the first conductive layer and the second conductive layer. The first structure comprises a first layer with a first carbon-based material and a plurality of second structures with piezoelectricity. Each of the plurality of second structures comprises a second layer with a second carbon-based material and a third layer adjacent to the second layer. The third layer comprises a material of two-dimensional crystals of unconventional stoichiometries such as Na2Cl crystals.

Abstract: The present invention discloses a catalytic hydrogenation method for carbon nine resin, comprising the following steps: 1) adding a Pt—W—Y/?-Al2O3 catalyst in the first half of a fixed bed, adding a Pd—Zr—Nd/?-Al2O3 catalyst in the second half of the fixed bed, and feeding hydrogen for reduction; and 2) catalytic hydrogenating the pretreated carbon nine resin in the fixed bed. In the present invention, different catalysts capable of reacting under the same catalytic conditions are added in the first and second halves of the fixed bed, and the two different catalysts play different roles, and can be active and complementary to each other under the same conditions. The synergistic effect of the two catalysts plays a good catalytic role. Moreover, the production process is simplified, and the production cost is saved.

Abstract: Disclosed are an antimycin compound and a preparation method and use thereof. The preparation method comprises: fermenting a marine actinomycete (Streptomyces sp.4-7) with a preservation number CCTCCNO: M2020953 to obtain a fermented product and soaking and extracting the fermented product with ethyl acetate to obtain a crude extract; and carrying out separation and purification by normal-phase silica gel column chromatography, reversed-phase MPLC, and semi-preparative reversed-phase high-performance liquid chromatography. The invention has the advantages of resistance against Botrytis cinerea and Penicillium citrinum.

Abstract: A mid-infrared gas sensor based on a tapered sub-wavelength grating slot waveguide comprises a lower cladding, a first tapered grating array and a second tapered grating array. The first tapered grating array and the second tapered grating array are disposed on an upper surface of the lower cladding. The first tapered grating array is located in front of the second tapered grating array. The first tapered grating array is formed by 5566 identical first core waveguides that are regularly distributed at intervals from left to right. The second tapered grating array is formed by 5566 identical second core waveguides that are regularly distributed at intervals from left to right. The first core waveguides and the second core waveguides are tapered waveguides. Upper sides and lower sides of the first core waveguides and the second core waveguides are isosceles trapezoids.

Abstract: An antimycin compound and a preparation method and use thereof are provided. The preparation method comprises: fermenting a marine actinomycete (Steptomyces sp.4-7) with a preservation number CCTCCNO: M2020953 to obtain a fermented product and soaking and extracting the fermented product with ethyl acetate to obtain a crude extract; and carrying out separation and purification by normal-phase silica gel column chromatography, reversed-phase MPLC, and semi-preparative reversed-phase high-performance liquid chromatography. The antimycin compound has the advantages of resistance against Botrytis cinerea and Penicillium citrinum.

Abstract: The invention discloses a digital sample plot for soil fauna in dry land and the construction method thereof, comprising the dry land with sample plots in the center, automatic monitoring equipment and power supply equipment; such equipment is set around, underground, on the surface of or above the sample plot; the invention realizes a full-coverage, all-weather and three-dimensional sample plot.

Abstract: Disclosed are a virtual parking space establishment system and a method. The virtual parking space establishment system includes a data acquiring module, a data processing module, a parking space control module, a wireless communication module and a client; the data acquiring module is used for acquiring traffic flow data; the data processing module is used for processing and analyzing the traffic flow data; the parking space control module is used for establishing or canceling virtual parking spaces according to analysis results of the traffic flow data; the wireless communication module is used for providing a wireless network link between the client and the parking space control module; the client is used for viewing virtual parking space information.

Abstract: A broadband panel array antenna includes a polarization layer, a radiating layer and a feed layer which are sequentially stacked from top to bottom. The feed layer is used for converting a single path of TE10 mode signals into a plurality of paths of same-power in-phase TE10 mode signals and transmitting the plurality of paths of TE10 mode signals to the radiating layer. The radiating layer is used for radiating the plurality of paths of TE10 mode signals from the feed layer to a free space. The polarization layer is used for rotating the polarization direction of an electric field generated by the radiating layer to reduce the side lobe in an E-plane direction diagram and an H-plane direction diagram. The broadband panel array antenna has the advantages of being low in side lobe, high in gain and efficiency, and low in machining cost.

Abstract: A method for preparing all-solid-state photonic crystal fiber preform by extrusion by aligning the center of the first jacking end of the first jacking rod with the center of the core outlet mold. The adverse effect on this part of extruded core glass by oxygen or other impurities in air during the extrusion out of the core outlets can be avoided. The defects on the core glass surface and the cladding glass surface can be effectively removed, and the purity and quality of the core component in the obtained fiber preform can be improved.

Abstract: The present invention discloses a Prunus persica polygalacturonase-inhibiting protein 1 (PpPGIP1) gene, and a cloning method and use thereof. The Prunus persica polygalacturonase-inhibiting protein 1 PpPGIP1 gene has a nucleotide sequence shown in SEQ ID NO: 1, and a protein encoded by the Prunus persica polygalacturonase-inhibiting protein 1 (PpPGIP1) gene has an amino acid sequence shown in SEQ ID NO: 2. The cloning method includes the following steps: (1) extracting total RNA from a peach, and subjecting the total RNA to reverse transcription to obtain cDNA, which serves as a template; (2) designing primers based on the PpPGIP1 gene sequence; and (3) Polymerase Chain Reaction (PCR) amplification: conducting PCR amplification to obtain a PpPGIP1 gene amplification product.

Abstract: A high-dimensional data nearest-neighbor query method based on variable-length hash codes is disclosed. Specifically, in this method, hash codes with the same code frequency are taken as a sub-data set, all the sub-data sets are ranked, a compression ratio is set for each sub-data set, the sub-data sets are compressed and trained according to the compression ratios, and hash codes and original codes corresponding to the trained sub-data sets are obtained; the hash code of each trained sub-data sets is copied to obtain multiple replicas, and the original codes and the corresponding replicas are strung to obtain strung hash codes which are integrated to form a final nearest-neighbor query table; and, a query code is obtained, and the nearest-neighbor query table is searched for a nearest-neighbor data set to complete query. The query efficiency and accuracy are greatly improved according to the invention.

Abstract: A reusable piezoelectric sensor for damage identification includes a piezoelectric ceramic plate and a metal box bonded to the surface of a test piece, where a wire through hole is formed in the center of a top plate of the metal box, and a side wall of the metal box extends vertically upwards to form a striking face for being struck to remove the metal box from the test piece; the piezoelectric ceramic plate arranged in the metal box is closely and fixedly bonded to a bottom plate of the metal box; and wires of the piezoelectric ceramic plate penetrate through the wire through hole to be connected to an external impedance analyzer. The reusable piezoelectric sensor for damage identification is easy to manufacture and convenient to operate and can effectively eliminate the testing error caused by the difference of the piezoelectric ceramic plate.

Abstract: The present invention discloses a catalytic hydrogenation method for carbon nine resin, comprising the following steps: 1) adding a Pt—W—Y/?-Al2O3 catalyst in the first half of a fixed bed, adding a Pd—Zr—Nd/?-Al2O3 catalyst in the second half of the fixed bed, and feeding hydrogen for reduction; and 2) catalytic hydrogenating the pretreated carbon nine resin in the fixed bed. In the present invention, different catalysts capable of reacting under the same catalytic conditions are added in the first and second halves of the fixed bed, and the two different catalysts play different roles, and can be active and complementary to each other under the same conditions. The synergistic effect of the two catalysts plays a good catalytic role. Moreover, the production process is simplified, and the production cost is saved.