Abstract: The present disclosure relates to a device and method for accurately measuring an azimuth angle and an elevation angle of mid-infrared laser light. The device includes a laser, an atomic gas cell, a filter, a displacement platform, and a beam mass spectrometer. Pump light generated by the laser enters the atomic gas cell along an optical axis which is a Z-axis for a spontaneous frequency conversion process, and a generated reference beam enters the beam mass spectrometer through the filter; target mid-infrared laser light and the pump light intersect in the atomic gas cell to induce a second frequency conversion process, and a generated beam to be measured enters the beam mass spectrometer through the filter; and the beam mass spectrometer is arranged on the displacement platform and simultaneously detect spot images of the reference beam and the beam to be measured at different positions, respectively.

Abstract: An integral optical resonant cavity for frequency conversion is provided. The integral optical resonant cavity includes: a housing, a cavity-length adjustment device, a temperature control device and a nonlinear crystal provided in the temperature control device; a first plano-concave mirror and a second plano-concave mirror included in the cavity-length adjustment device and a nonlinear crystal form the optical resonant cavity; and light passes through the first plano-concave mirror, the nonlinear crystal and the second plano-concave mirror sequentially. The stability of the length of the optical resonant cavity is improved through an integral design thereof, and the stability of the temperature of the nonlinear crystal in the integral optical resonant cavity is improved through the temperature control device, thereby stably controlling relative phases between light fields for the frequency conversion in the resonant cavity.

Abstract: A liquid crystal coherent transparent display screen and a liquid crystal-laser transparent display system are provided. The polarizer, the analyzer and the optical filters in the conventional technology are replaced by an optical resonant microcavity formed by the first partial reflector and the second partial reflector in the liquid crystal coherent transparent display screen, thereby improving the light transmittance of liquid crystal transparent display.

Abstract: A device for creating hollow tubes of crystalline magnesium sulphate sized a micron pertains to the production technology for inorganic micron-scale materials. The device consist of two halogenation tanks, a solar collector, a temperature-controlled crystallization chamber, a centrifuge, a conveyor belt, and a dryer. The solar collector is connected to a heat pipe at the bottom of a brine pool to form a circulation path. Said method is to convert high magnesium brine into saturated brine with a Mg2+:Na+ mass ratio between (8˜15):1 by a brine blending operation at a temperature of 60° C.˜90° C. it is controlled to be cooled and crystallized at a cooling rate of 0.6˜2.0° C./min, solid-liquid centrifugal separation is carried out when it is cooled down to 40˜48.5° C., and the solid phase is dried at a temperature of 48.5˜70° C., and finally micron-sized crystalline magnesium sulfate hollow tubes are obtained.

Abstract: The present disclosure belongs to the field of photoacoustic signal detection, and specifically relates to a quantum-enhanced all-optical photoacoustic signal detection device and method. The problem of low sensitivity of photoacoustic signals based on interference measurement is solved, and high-sensitivity detection of photoacoustic signals generated by living organisms including human bodies can be achieved. A degenerate optical parametric oscillator based on a first-type phase matching crystals is used for preparing a vacuum squeezed state light field, a coherent control technology is used for locking the squeezed angle to obtain the quadrature phase vacuum squeezed state, the prepared quadrature phase vacuum squeezed state light field is injected into the vacuum channel of a Michelson interferometer, and a balanced homodyne detection mode is used for achieving detection of the quantum-enhanced photoacoustic signals.

Abstract: The present disclosure provides a kinship verification method based on generalized multi-view graph embedding, including the following steps: extracting features for multiple views of facial images from a training set and generating sample pair; constructing an intrinsic graph and a penalty graph of each of the multiple views based on semantic information, and converting and correcting a graph embedding method; implementing generalized fusion for the multiple views, and solving generalized eigenvalue decomposition; and calculating a similarity between the facial images, and outputting a kinship discrimination result.

Abstract: An apparatus and a method for measuring a microwave electric field at continuous frequencies based on an alternating current (AC) Stark effect of Rydberg atoms. A cesium vapor cell is used as an atomic sample cell. A cesium atom is excited to a Rydberg state by using detection light and coupling light that are emitted by two laser light sources, an electromagnetically induced transparency spectrum is generated. Further, a strong electric field is used as a local field EL, to cause AC Stark frequency shift and splitting of a Rydberg energy level. ES of to-be-detected signal electric field is applied. In this case, the Rydberg atom serves as a frequency converter, to directly read a beat frequency signal ?f of the local field and the signal field. From the beat signal, the strength of Es of signal filed can be directly read out.

Abstract: A method for ecological filling with mixed coal gangue and fly ash includes the following steps: S1: construction of a double-impermeable base layer: leveling a pit or gully, laying a fly ash-based cementitious material, compacting and curing; spraying a layer of polymer waterproof coating on a surface of the fly ash-based cementitious material, and fully curing to obtain a double-impermeable protective structure; S2: three-dimensional layered filling: dumping coal gangue and fly ash in sequence on the double-impermeable protective structure formed in S1, where the coal gangue and the fly ash are three-dimensionally layered and well graded; the coal gangue is coal gangue after coal washing, which is used as an aggregate; the fly ash is used as a filler and cementitious material to achieve a compact filling structure; and S3: rolling: rolling by a roller after the three-dimensional layered filling.

Abstract: A magnesium-based fly ash porous sound-absorbing material with a surface hydrophobically modified, and a preparation method thereof are provided. In the preparation method, a basic magnesium sulfate cement is adopted as a cementing agent and a fly ash is adopted as a mineral admixture to prepare a slurry; foaming is conducted through a physical foaming process in a foaming machine to obtain a foam; and the foam is mixed with the slurry, and a resulting mixture is poured and cured, and then subjected to a surface hydrophobic modification through vapor deposition to obtain the sound-absorbing material. The sound-absorbing material has a density of 251 kg/m3 to 306 kg/m3, a noise reduction coefficient (NRC) of 0.65 to 0.7, a compressive strength of 1.8 MPa to 2.2 MPa, and a water contact angle of 129° to 151°.

Abstract: A frequency measurement method and a system thereof are provided. The method includes: generating to-be-detected emergent light under an action of the electro-optical crystal when a light source irradiates an electro-optical crystal disposed in the microwave electric field; detecting, by a single-photon detector, the to-be-detected emergent light to obtain a detection result of the single-photon detector; and determining a frequency of the microwave signal based on the detection result of the single-photon detector and a Fourier transform algorithm.

Abstract: A method for ecological filling with mixed coal gangue and fly ash includes the following steps: S1: construction of a double-impermeable base layer: leveling a pit or gully, laying a fly ash-based cementitious material, compacting and curing; spraying a layer of polymer waterproof coating on a surface of the fly ash-based cementitious material, and fully curing to obtain a double-impermeable protective structure; S2: three-dimensional layered filling: dumping coal gangue and fly ash in sequence on the double-impermeable protective structure formed in S1, where the coal gangue and the fly ash are three-dimensionally layered and well graded; the coal gangue is coal gangue after coal washing, which is used as an aggregate; the fly ash is used as a filler and cementitious material to achieve a compact filling structure; and S3: rolling: rolling by a roller after the three-dimensional layered filling.

Abstract: The present disclosure relates to a test paper counting technology, in particular to a portable test paper counting device and method based on a single photon detector. A portable test paper counting device based on a single photon detector is provided, which includes a box-shaped housing, two guide rail pairs, two hanger rods, a laser, a reflecting mirror, a single photon detector, a power supply, and a PC computer. A rectangular operating hole penetrating from left to right is formed in a lower edge of a right side wall of the box-shaped housing. A right part of a bottom wall of the box-shaped housing is provided with an assembly hole penetrating from up to down. A left side wall of the box-shaped housing is provided with a threading hole penetrating from left to right. Sliders of the two guide rail pairs both face downwards.

Abstract: The present disclosure relates to the field of ecological restoration of a coal gangue hill, and in particular, to a solid waste-based porous material, a method for preparing the solid waste-based porous material, and a method of ecological restoration of the coal gangue hill by applying the solid waste-based porous material. A coal-based solid waste restoration material and mycorrhizal solid bacterial agent are mixed to restore the coal gangue hill, the coal-based solid waste restoration material is prepared by mixing coal-based solid waste porous materials, low-rank coal, and waste organic matter and adding a microbial quickly decomposition agent for aerobic fermentation and standing.

Abstract: A Ni—Al2O3@Al2O3—SiO2 catalyst with coated structure is provided. The catalyst has a specific surface area of 98 m2/g to 245 m2/g, and a pore volume of 0.25 cm3/g to 1.1 cm3/g. A mass ratio of an Al2O3 carrier to active component Ni in the catalyst is Al2O3:Ni=100:4˜26, a mass ratio of the Al2O3 carrier to an Al2O3—SiO2 coating layer is Al2O3:Al2O3—SiO2=100:0.1˜3, and a molar ratio of Al to Si in the Al2O3—SiO2 coating layer is 0.01 to 1. Ni particles are distributed on a surface of the Al2O3 carrier in an amorphous or highly dispersed state and have a grain size less than or equal to 8 nm, and the coating layer is filled among the Ni particles.

Abstract: The present disclosure relates to the field of ecological restoration of a coal gangue hill, and in particular, to a solid waste-based porous material, a method for preparing the solid waste-based porous material, and a method of ecological restoration of the coal gangue hill by applying the solid waste-based porous material. A coal-based solid waste restoration material and mycorrhizal solid bacterial agent are mixed to restore the coal gangue hill, the coal-based solid waste restoration material is prepared by mixing coal-based solid waste porous materials, low-rank coal, and waste organic matter and adding a microbial quickly decomposition agent for aerobic fermentation and standing.

Abstract: A device and a method for measuring thermal load caused by excited state absorption in laser gain crystal are disclosed. Thermal focal lengths on the tangential and sagittal planes of the laser gain crystal are obtained by obtaining the threshold when the pump power is decreased, the optimal operating point, and cavity parameters of the single-frequency laser. Individual ABCD matrices of the laser gain crystal on the tangential plane and the sagittal plane are obtained based on thermal focal length.

Abstract: A frequency measurement method and a system thereof are provided. The method includes: generating to-be-detected emergent light under an action of the electro-optical crystal when a light source irradiates an electro-optical crystal disposed in the microwave electric field; detecting, by a single-photon detector, the to-be-detected emergent light to obtain a detection result of the single-photon detector; and determining a frequency of the microwave signal based on the detection result of the single-photon detector and a Fourier transform algorithm.

Abstract: The disclosure relates to a quartz-enhanced photoacoustic spectroscopy gas detection apparatus and method based on beat effect. Provided is a quartz-enhanced photoacoustic spectroscopy gas detection apparatus based on beat effect, comprising a photoacoustic signal detection module, a gas chamber, a light source module and a data acquisition module. In the present invention, by detecting the beat signal generated by mixing the piezoelectric signal output from the quartz tuning fork with the demodulation signal of the lock-in amplifier, the electrical parameters of the quartz crystal oscillator and the concentration of the gas to be measured can be obtained accurately in a time period on the order of milliseconds.

Abstract: A pulsed light high-speed polarization locking method of a continuous variable quantum key distribution system is disclosed. An integral type optical detector is used for converting energy of a single pulsed light into a peak voltage of an output electric pulse in real time so as to achieve real-time measurement of light pulse energy without conducting high-speed data sampling and simplify the data acquisition and processing. By utilizing the FPGA hardware, a conditional simulated annealing algorithm is quickly operated to search the target polarization state and achieve high-speed polarization locking under the pulsed light. In addition, the power change of a local oscillator is monitored in real time to strengthen the resistance of the system against local oscillator dithering attack. The present invention can effectively solve a problem of rapid fluctuations of polarization state of pulsed light caused by complex external environments.

Abstract: A device and a method for measuring a thermal load caused by energy transfer upconversion in a laser gain crystal. Increasing the pump power multiple times so that the power meter obtains multiple thresholds for a single-frequency laser; obtaining an average pump threshold of the output laser; obtaining cavity parameters of the single-frequency laser; obtaining thermal focal lengths on the tangential and sagittal planes of the laser gain crystal inside the single-frequency laser; obtaining individual ABCD matrices of the laser system on the tangential and the sagittal planes; obtaining a thermal load at the threshold based on the ABCD transfer matrix of the laser gain crystal on the tangential plane, the ABCD transfer matrix of the laser gain crystal on the sagittal plane, and the average pump threshold of the laser system; obtaining a thermal load caused by ETU at threshold based on the thermal load at the threshold.