Abstract: Embodiments provide a method for geomagnetically detecting a submarine cable, including: performing a preliminary detection by controlling an underwater robot equipped with a proton magnetometer; determining a preliminary direction and location of the cable based on preliminary detection information; controlling the underwater robot equipped with the proton magnetometer and two fluxgate magnetometers to launch into the water; controlling the underwater robot to travel over the cable and determining specific location information of the cable; controlling a heading of the underwater robot to move along the preliminary direction of the cable; and controlling the underwater robot equipped with the proton magnetometer and the two fluxgate magnetometers to launch into the water; determining whether a fault in the submarine cable occurs and a location of a fault point, based on Z-axis components of the general geomagnetic field and launching depth data of the underwater robot.

Abstract: A method of calibrating an instrument for surgical intervention is provided. The instrument to be calibrated has a tip at a distal end thereof and a navigation array that is spaced from the distal end and is detectable in space. The navigation array has a fixed spatial and angular relationship with the tip. The method comprises the steps of: placing a calibrator on the tip of the instrument such that the tip is positioned within the calibrator at a known displacement from the centre of the calibrator, the calibrator having a circular shape and being detectable as a single point in space; detecting the position of the navigation array and the centre of the calibrator; and determining the position of the centre of the calibrator relative to the navigation array, thereby calibrating the position of the tip of the instrument relative to the navigation array. There is also provided a calibrator for use in such a method.

Abstract: A mine cooling and dehumidifying system includes a compressor, a gas-liquid separator, an evaporator, a condenser and an expansion valve. The evaporator is in an air supply well, and the condenser is in a return air well; the compressor, the gas-liquid separator and the expansion valve are all between the air supply well and the return air well; an inlet of the compressor is connected to a refrigerant outlet of the evaporator through the gas-liquid separator, and a refrigerant inlet of the evaporator is connected with an outlet of the expansion valve; an inlet of the expansion valve is connected with a refrigerant outlet of the condenser, and a refrigerant inlet of the condenser is connected with an outlet of the compressor. In the present disclosure, by vapor compression type refrigeration cycle, the downhole air heat is transferred to the return air and then discharged to the ground.

Abstract: A high-speed and large-current adjustable pulse circuit, an operating circuit and an operating method of a phase-change memory are provided. The high-speed and large-current adjustable pulse circuit is provided with a clamping structure, a current mirror structure and a leakage current shutdown structure. The clamping structure including a clamping operational amplifier and a first MOS transistor is configured to generate a reference current. The current mirror structure is configured to generate an output current proportional to the reference current. The leakage current shutdown structure is configured to turn off the current mirror structure and reduce leakage current when pulse disappear. In this way, a device with an adjustable current and a reduced leakage current is realized.

Abstract: Disclosed are an antimicrobial high-entropy alloy FeCoNiCrCe and a preparation method thereof, falling within the technical field of high-entropy alloys. The high-entropy alloy in the present disclosure has an expression: FeCoNiCrCex, 0.1?x?0.5, and a proportion of each element is a molar ratio. In the present disclosure, the microstructure and mechanical and antimicrobial performances of high-entropy alloy FeCoNiCrCex are improved by adjusting a content of Ce.

Abstract: The disclosure relates to a phase change thermal storage ceramic having high service temperature and improved utilization rate and utilization efficiency of heat. It is prepared at a low cost with a simple, easy-to-industrially-realized method. A mixture is obtained by mixing and stirring evenly 50-85 wt % of fused mullite powder, 10-45 wt % of pretreated aluminum-silicon alloy powder, and 3-8 wt % of ball clay. A ceramic body is formed by press molding the mixture at 80-150 MPa. The ceramic body is cured at 25-28° C. and a relative humidity of 70-75 RH for 24-36 h, dried at 80-120° C. for 24-36 h, and held at 1,100-1,300° C. for 3-5 h to prepare the phase change thermal storage ceramic. The pretreated aluminum-silicon alloy powder is prepared by holding aluminum-silicon alloy powder in water vapor at 0.02-0.20 MPa for 0.5-3 h to impregnate in an alkaline silica sol and drying the impregnated powder.

Abstract: A nonlinear optical device includes two coupling systems. A coupling coefficient between the two coupling systems is regulated and controlled. During operation, the pump light input from a straight waveguide is coupled into the second coupling system through the first coupling system and obtains great resonance enhancement in the second coupling system, so it is ensured that the second coupling system is in a high energy state. For signal light input from the same end of the straight waveguide, the signal light enters a resonator of the second coupling system through the coupling between the first and second coupling systems. A nonlinear effect of the system mainly occurs in the resonator of the second coupling system because in the resonator of the second coupling system, the pump light is in a great resonance enhancement. The entire resonator is in a high energy state.

Abstract: A holographic wavefront printing system and method are provided. A two-dimension digital blazed grating is loaded on a phase hologram, and the emergent direction of active region diffracted light is adjusted to prevent overlapping with the dead region diffracted light after being Fourier transformed by a lens, and a phase spatial light modulator is inclined by a preset angle to change the emergent direction of the diffracted light, such that the dead region zeroth-order and first-order diffracted light on a focusing surface are symmetrical with respect to a main optical axis of a first lens, the frequency spectrum center of active region zeroth-order diffracted light is then loaded to the original frequency spectrum center without information change. In this way, the adverse effects of the dead region diffracted light and active region high-order diffracted light of the phase spatial light modulator on holographic wavefront printing are eliminated.

Abstract: Provided is a method for preparing copper azide and cuprous azide encapsulated by conductive metal-organic framework. The method uses a conductive copper-containing metal-organic framework material as a precursor, and completes the azidation of the precursor by means of a liquid-solid electrochemical azidation reaction. Copper azide and cuprous azide nanocrystals are highly uniformly embedded within a conductive framework, which may effectively avoid the agglomeration of copper azide and cuprous azide, and reduce static charge generated by friction, displacement, and the like. Meanwhile, the conductive framework may promote the effective transfer of charge, avoid the accumulation of static charge, and improve the electrostatic safety.

Abstract: A single-photon Raman optical frequency comb source is provided, including: a light source assembly, a filtering mechanism, at least three electro-optical modulators, a wavelength division multiplexer and a single photon generating mechanism. The light source assembly is configured to generate a Raman scattering light. The filtering mechanism is configured to pass a light having a specific wavelength, to filter the Raman scattering light and obtain at least three Raman scattering spectral lines. Each electro-optical modulator is configured to modulate a frequency of one of the Raman scattering spectrum lines in one-to-one correspondence, so as to cause a frequency shift of the Raman scattering spectrum line. The wavelength division multiplexer is configured to multiplex all modulated Raman scattering spectral lines and output a Raman optical frequency comb. The single photon generating mechanism is configured to adjust the Raman optical frequency comb to obtain a single-photon Raman optical frequency comb.

Abstract: A high-strength steel with excellent neutral aqueous medium corrosion resistance, and a preparation method and application thereof are provided. A steel plate is designed with cheap chemical compositions of low carbon, low silicon and medium manganese, and is completely free of precious metal elements such as Cr, Ni and Cu, thereby greatly reducing the material cost. According to the present invention, instead of the traditional Al deoxidation technology, Si or Si—Mn deoxidation assisted by Zr—Ti composite deoxidation is used to form a fine, dispersed and uniform composite oxysulfide, which greatly decreases the density of corrosion-active inclusions, and obviously improves the neutral aqueous medium corrosion resistance. Through the design of low carbon equivalent, the steel plate has excellent welding performance; and the composite microalloying of Nb, Zr and Ti is adopted to cooperate with the TMCP rolling parameter control, so that the steel plate has high strength and good extensibility.

Abstract: A Ni-free micro-alloyed high-strength steel with ultra-low temperature toughness and a preparation method thereof are provided. The micro-alloyed high-strength steel includes the following chemical components by mass percentage: 0.011% to 0.099% of C, 0.051% to 0.24% of Si, 1.21% to 1.49% of Mn, 0.030% to 0.059% of Nb, 0.009% to 0.016% of Ti, 0.001% to 0.018% of Zr, 0.001% to 0.018% of rare earth (RE), and the balance of Fe and inevitable impurities. The mass percentage also meet the following formulas: 0.21%<C+Si<0.24%, and Si/C=1 to 8; 0.02%<Nb+Ti<0.05%, and Nb/Ti=1 to 3; 0.010%<Zr+RE<0.019%, and Zr/RE=1 to 6. The micro-alloyed high-strength steel uses a completely different composition design (i.e., a simple low-cost Ni-free composition design) to realize ultra-low temperature toughness, and with the help of Zr+RE compound deoxidation and Nb+Ti compound micro-alloying technologies, realizes ultra-low temperature toughness at ?100° C. to ?120° C.

Abstract: A seawater corrosion-resistant marine engineering steel and a preparation method thereof are provided. The seawater corrosion-resistant marine engineering steel consists of the following chemical compositions in percentage by mass: C: 0.011-0.069%, Si: 0.11-0.29%, Cr: 1.51-1.99%, Nb: 0.02-0.05%, Zr: 0.01-0.02%, RE: 0.0034-0.02%, and the balance of Fe and inevitable impurities. The mass percentages of Zr element and RE element also satisfy the following formulas: 0.01%<Zr+RE<0.02%, and Zr/RE=1-3. The marine engineering steel is designed with cheap chemical compositions of low carbon, low silicon and medium chromium, and is completely free of valuable corrosion-resistant metal elements such as Ni and Cu. Instead of the traditional Al deoxidization technology, Si deoxidization assisted by Zr?RE composite deoxidization is used to form a fine, dispersed and uniform composite oxysulfide.

Abstract: The disclosure belongs to the technical field related to additive manufacturing model preprocessing, and discloses a field-based additive manufacturing digital model feature identification and extraction method and device, the method can convert the digital model represented by the facet into a signed distance field and introduce a simulated physical field of the forming/service simulation, the feature distance field after the frequency domain analysis filtering, and the geometric feature field obtained by the multi-precision convolution unit analysis according to the requirement of feature to be identified, then, multiple fields are combined to realize feature classification determination and labeling of features, and finally feature extraction is completed based on field data and isosurface and isoline reconstruction algorithms.

Abstract: A composite additive for forming inclusions with a core-shell structure, a preparation method and a smelting method are provided. The composite additive includes the following chemical components by mass percentage: Fe: 41-59%, Zr: 5-11%, Ti: 14-26%, Mg: 11-19%, and RE: 4-10%, in which the mass percentage content of Zr element, Ti element, Mg element and RE element satisfies a formula: (Ti+Mg+RE)/Zr=4-8. The composite additive for forming inclusions with a core-shell structure has the characteristics of fineness, spheroidization and obvious dispersion effect. This type of inclusions has a bulk modulus similar to that of the iron matrix, which can significantly improve the plasticity, toughness, fatigue resistance, local corrosion resistance, welding performance, cold bending performance, etc. of steel materials, suitable for steel types with strict requirements on the shape of inclusions, such as marine steel, pipeline steel, container steel, cold heading steel, tool and die steel, etc.

Abstract: Techniques for measuring vacuum pressure using a memristor element are described. A vacuum sensor can include a memristor element having a semiconductor substrate, a memristive material layer, and a conductive electrode. The off-state resistance of the memristor element can be sensitive to changes in ambient pressure at the element. The off-state resistance of the memristor element may also exhibit a well-defined increase at pressures below a threshold pressure. Measurement of the off-state resistance may be obtained with low power consumption and without changing the resistance or switching the state of the memristor element. The measurements may be used to both determine a leak rate of the ambient pressure within the volume of interest and determine if the sensor is exposed to vacuum pressure below the threshold pressure.

Abstract: Disclosed are a method for processing and recycling an ultrathin lithium foil and a product, which belongs to the field of lithium-ion batteries. According to the disclosure, a liquid-phase thinning agent is adopted to perform a contact reaction with a lithium metal, the fabricated ultrathin lithium foil has a thickness of 20 ?m or less, the surface is flat, the thickness can be randomly regulated, and the uniformity is good. The method of the disclosure can also recycle a lithium-containing byproduct generated in the preparation process. When the ultrathin metal lithium foil prepared by the disclosure is used as a metal lithium negative electrode of a lithium battery, the energy density of the battery can be improved, and the battery manufacturing cost is reduced. The ultrathin metal lithium foil can also be used to supplement lithium for other types of electrode materials, thereby a broad application prospect is achieved.

Abstract: The present disclosure provides a method for preparing a catalyst for pyrolysis of waste plastics to produce oil, comprising: washing and modifying coal gangue powder with acid, and then placing in an alkaline solution, etching under magnetic stirring for 20-30 minutes, and washing with water until neutral; placing the catalyst washed until neutral in a metal solution, loading the metal by impregnation, and then filtering and washing; then placing the catalyst in the molding machine and adding adhesive and water, to compress into a suitable shape, drying, and finally calcinating to activate to obtain a product. The present disclosure not only solves the problem of waste plastic pollution, but also obtains fuel oil with high valuable products while reducing the cost of waste plastic treatment, and also improves the yield of fuel oil.

Abstract: Disclosed are a high-throughput preparation device for metal fiber based on multi powder and a method for preparing a metal fiber using the device. The high-throughput preparation device includes a metal powder conveying system, a metal powder mixing system, a metal powder melting system and a metal fiber forming system which are connected in sequence, where the metal powder melting system includes an induction powder melting device and a laser powder melting device which are independently disposed. The method for preparing a metal fiber using the high-throughput preparation device includes four steps: powder conveying, powder mixing, melting and forming.

Abstract: The disclosure provides a frequency support method, device and wind farm for a wind farm and belongs to the technical field of new energy power generation and grid connection. In the frequency support method, a state that can reflect a frequency modulation capability of a wind turbine is designed, measured, and recorded as a consistency factor of frequency modulation. Each wind turbine is controlled to exchange the consistency factors with two adjacent wind turbines. Each wind turbine combines its own consistency factors with the consistency factors of two adjacent wind turbines to generate consistent added power through a PI link and adjusts real-time frequency modulation output based on the consistency added power. In this way, the states of the wind turbines in the wind farm are similar during the frequency support process, so that a reasonable distribution of frequency support power is achieved.