267 results about "Single pass" patented technology

The invention discloses a method for refining grains of a titanium alloy. According to the method, an original low-oxygen-content titanium alloy plate is subjected to cryogenic pretreatment, the temperature of the core of the original low-oxygen-content titanium alloy plate is reduced to a certain temperature, then the cryogenic low-oxygen-content titanium alloy plate is fed into a rolling mill, the single-pass reduction rate is controlled, cryogenic rolling is completed, high refinement and uniform distribution of crystal grains are achieved, and the low-oxygen-content titanium alloy plate is obtained. And the rolled titanium alloy plate is subjected to subzero treatment again, and the titanium alloy plate of the complex twin crystal structure formed by intersection of {11-22} and {10-11} twin crystals is obtained. The method has the beneficial effects that under the synergistic effect of low oxygen and deep cooling, even under the extremely small deformation amount, the cross effect of various twin crystal systems can be efficiently activated, a high-density and complex twin crystal structure is formed, high refinement and uniform distribution of crystal grains are achieved, then the mechanical strength and low-temperature toughness of the material are remarkably improved, and the service life of the material is prolonged. And the application requirements in a severe low-temperature service environment are met.

The invention relates to a continuous production method of high-purity tetraethoxysilane, and belongs to the technical field of tetraethoxysilane preparation. The method comprises a raw material pretreatment stage and a purification and rectification stage: in the pretreatment stage, silicon tetrachloride and ethanol are subjected to an esterification reaction in a molar ratio of 1: (3-4) under the protection of nitrogen, the pH is adjusted to be neutral through triethylamine, and triethylamine hydrochloride is removed through reduced pressure distillation; then, a cerium oxide-molecular sieve composite adsorbent with the specific surface area larger than or equal to 800 m / g and the pore diameter of 2-5 nm is adopted for dehydration under the pressure of 0.8-1.2 MPa till the water content is smaller than or equal to 5 ppm, and volatile impurities are removed through high-purity nitrogen purging; in the purification stage, metal ions and Cl are synergistically removed through a titanate modified resin layer and a nano TiOtube layer, and then step-by-step separation is performed through a four-stage differential pressure rectifying tower. Through collaborative optimization of structural design of the composite adsorbent, construction of an organic-inorganic hybrid interface of the resin layer and pressure gradient rectification, 72-hour continuous production is achieved, the single-pass yield of the product is 92%, and the total amount of metal impurities is smaller than or equal to 5 ppb.

The present invention relates to the field of tram track laying construction. Disclosed is a method for laying a jointed ballasted track for trams on small-radius curves. In the method, by adjusting and fixing track alignment before ballast laying and track finishing, the conventional construction sequence of ballast laying and track finishing is changed, track lifting and alignment adjustment for small-radius curves are carried out prior to ballast laying and tamping, and during track laying, sleepers are densely arranged at rail joints, and concrete buttresses are added beside the sleepers to secure the sleepers in place and counteract the bending stress of rails, ensuring precise control of track alignment and elevation on the small-radius curves, and realizing laying of the jointed ballasted track for trams on the small-radius curves. After construction, ballast laying and track finishing on the small-radius curves can meet track operation requirements in a single pass, ensuring smooth and safe tram operation.

The utility model relates to the technical field of scanning and printing, in particular to a multifunctional singlepass printer. Comprising a rack assembly which is provided with a belt used for conveying fabric, the fabric is laid on the belt, and a printing area is arranged on the fabric; the scanning assembly is arranged above the belt, and a nozzle array is arranged on the scanning assembly and is suitable for scanning and printing a printing area on the fabric; and the moving assembly is arranged on the rack assembly and the scanning assembly and is suitable for driving the scanning assembly to move in the length direction of the belt, the width direction of the length direction of the belt and the direction perpendicular to the length direction of the belt. When the scanning assembly changes the direction in the length direction of the belt every time, the distance of the multiple spray heads is moved in the width direction of the belt, so that the problem of color deviation caused by needle deflection and oblique spraying of the spray heads and the difference between the spray heads is solved. According to the invention, various printing modes can be provided to meet market requirements.

The invention relates to a quasi-differential wavefront segmentation double-beam interference device with a planar light path structural design, which has the structural characteristic of a non-closed optical path for transmitting a measurement light beam in a one-way manner. Space coherent light of a transverse mode vector filtering mechanism based on the Huygens principle / phased array principle instead of homologous transmission time coherent light is used as each light source, and a non-closed optical path is realized under the cooperation of a one-way transmission mode on a divided measuring light beam. The problem that the sum of the loop wavelength increment or the frequency increment of a closed path interference device is zero is solved, so that the purpose of measuring the first-level effect of anisotropic physical parameters of a measured object in a linear system is achieved, and the device is particularly suitable for immersion type online measurement. The optical elements have stable performance and sound self-adaptive mechanism and self-diagnosis capability through careful layout of the optical elements; and the method also has wide application prospects in basic physical research and novel navigation / positioning systems. The invention also provides a differential wavefront segmentation and semi-transparent and semi-reflective mirror beam combination interferometer device based on the planar light path structure design, and a wavefront segmentation interferometer device based on the planar light path structure design and provided with a pre-crossing area and a bending type one-way-two-way-common mode combination light path structure. The invention relates to a wavefront segmentation interferometer device of a one-way-two-way combined light path structure which is designed based on a planar light path structure and adopts polarization light splitting-beam combination, optical rotation processing of a reference light beam and original path returning, and a use method of an interference device.

A graphics processing system configured to process an image comprising a plurality of rendered pixels, the system being configured to divide the image into a plurality of tiles, each tile comprising a subset of the rendered pixels of the image and corresponding to a plurality of display pixels, the system comprising: a tile on-chip memory; and a processor, wherein the processor is configured to perform a processing pass for at least one rendered pixel in the image, comprising: rendering the rendered pixel by: determining a set of samples, each sample having a respective position in the rendered pixel and the positions collectively having a sampling density in the rendered pixel; shading the rendered pixel at a first resolution to give a shading result for the rendered pixel; writing a shading value for each of the set of samples to the tile on-chip memory based on the shading result; and storing an up-scaled representation of the rendered pixel in the tile on-chip memory by determining, from the shading values for the set of samples, a display pixel shading value for each of a plurality of display pixels overlapping the rendered pixel at a target resolution greater than the first resolution.

A preparation method of a Ti-5553 titanium alloy plate with a grade fine grain double-state structure adopts cross-phase transformation point free forging to prepare a Ti-5553 titanium alloy plate blank, in the cross-phase transformation point free forging, the initial forging temperature of a forging stock is in a temperature zone of 45-95 DEG C above the phase transformation point, the lower limit of the final forging temperature is 650 DEG C, short-process and low-cost preparation of the plate blank is achieved, and the production cost is reduced. And the surface integrity and the deformation uniformity in the thickness direction of the plate blank in the hot rolling process in the temperature zone below the subsequent phase transformation point are guaranteed through the fine grain structure. According to the method, the strain range of a single pass is 0.2-0.25, the strain value of the single pass is larger than or equal to the critical formation strain of DDW of the Ti-5553 alloy, and therefore the number of DDW in the alloy can be increased through hot rolling in the temperature zone below the phase transformation point of each pass. The DDW in the plate is sharply increased after multi-pass hot rolling in the temperature zone below the phase transformation point, and grain refinement is sufficient. The microscopic grain size of the Ti-5553 hot-rolled plate prepared by the method is higher than 7 grade.

The disclosure relates to systems and methods for increasing the functional capabilities of a sorbent-based dialysis system. The systems and methods allow for the mode of operation of the dialysis system to be switched between single pass mode and a sorbent based multi-pass mode by controlling an amount of water added to the dialysate between 0% to 100% of the dialysate flow rate.

Techniques for providing analytical storage systems capable of executing analytical data operations “near-storage”. The techniques include receiving a command from a host computer, in which the command defines match criteria specifying a character string, and an address range of a data table. The techniques include identifying one or more character strings in the data table as matching the character string specified by the match criteria within the address range of the data table. The techniques include providing information pertaining to the identified character strings for use by the host computer. The techniques include computing information that enables estimating the number of unique values of a specified subset of data. The techniques can reduce, in a single pass, amounts of data to be provided to a host computer during execution of analytical data operations “near-storage”. The techniques can be implemented in systems and devices with reduced technological complexity and simplified programmability.

An optical measurement system may improve the accuracy with which it estimates distances to surrounding objects by upgrading various aspects of its data path. Spatial resolution may be increased by subdividing histogram buckets or integration registers based on spatial location. Saturation at any point in the data path can be detected and used to stop counting photons in individual pixels, which can then be normalized after a measurement is over. Multiple peaks can be detected using recursive or iterative techniques to identify a largest remaining peak at each stage. Instead of iterating through the histogram memory multiple times, a threshold can be pre-calculated based on an estimated ambient noise level, and peaks can be detected in a single pass.

A kind of manual control type point glue machine and point glue method, the point glue machine includes: pressure vessel, support, two-component point glue valve being installed in support, two pipelines being communicated two glue inlets of two-component point glue valve and the pressure vessel, glue nozzle being combined two glue outlets of two-component point glue valve, foot switch, with two-component point glue valve and foot switch electric connection, controller for controlling two-component point glue valve and switch between three kinds of states of double pass, single pass and closed.The method includes: controlling two-component point glue valve in double pass state, and quickly glue to product;After quick glue, control two-component point glue valve in single pass state, and slowly glue to the product.Waves and bubbles generated by early quick glue can be eliminated by later slow glue.

The invention provides a preparation method of a composite plate with excellent interface bonding, which comprises the steps of blank surface treatment, blank assembly and plate sealing, welding, vacuumizing, heating, rolling, cooling, heat treatment and plate splitting, in the blank assembly and plate sealing steps, blanks are placed according to the sequence of base material, covering material, covering material and base material to obtain a composite blank; in the rolling step, if tcp / tsp is larger than or equal to 4, the rough rolling single-pass rolling reduction is larger than or equal to 30 mm, and the rough rolling pass is larger than or equal to 1; the single-pass rolling reduction of the first three passes of finish rolling is larger than or equal to 25 mm, and the pass of finish rolling is smaller than or equal to 7; if tcp / tsp is smaller than 4, the rough rolling single-pass rolling reduction is larger than or equal to 35 mm, and the rough rolling pass is larger than or equal to 3; the finish rolling single-pass rolling reduction is smaller than or equal to 25 mm, the finish rolling pass is smaller than or equal to 7, and the total compression ratio CR is larger than or equal to 7; tcp is the target thickness of the base material in the composite board, tsp is the target thickness of the covering material in the composite board, and the unit is mm. The rolling reduction is controlled through the target proportion of the base material and the covering material in the composite board, and combination at different thickness ratios is promoted.

The utility model relates to a kind of lead-acid battery plate production technical field, specifically related to a kind of lead-acid battery plate coating device. Including frame, two symmetrical coating mechanisms of upper and lower setting are installed in frame one side, and roller mechanism is installed on the frame of coating mechanism side, it is characterized in that, two supporting rollers are rotatably arranged on the frame of roller mechanism side, outer smearing edge mechanism, inner smearing edge mechanism and cleaning mechanism are sequentially arranged between the two supporting rollers. The device integrates coating, rolling, smearing and cleaning functions, and the full-process treatment of coating can be completed by single pass of the grid, avoiding deformation or pollution of lead paste caused by multiple handling, significantly improving the production yield and efficiency of the plate.

The present invention relates to a method for checking a train count in a section, a medium, and a system. The method comprises the following steps: configuring check rules, and reading all the check rules from a configuration file by means of OGT software; traversing one-way trips of all trains on the basis of a timetable, and when the one-way trips match any section in the check rules, storing section entering and leaving records into a section entering and leaving record list; when traversal has been completed, sorting the section entering and leaving record list in chronological order of time points to obtain section entering and leaving information of all the trains along the time axis; traversing the section entering and leaving information, and obtaining a total train count in each section by means of a counter; and when the total train count in the section is greater than or equal to a train count upper limit, recording one piece of alarm information upon each change of the counter. Compared with the prior art, the present invention can achieve refinement of timetable compilation by checking counts of trains simultaneously present in sections, thereby improving operation efficiency and ensuring safety.

A method of printing an image from a printhead module having a plurality of horizontal rows of nozzles. Each row of nozzles has a main row portion and a corresponding drop row portion vertically offset from the main row portion. The method includes the steps of determining a predetermined delay for the drop row portions based on the offset, a print speed, and a print resolution; assigning dot data for an image row to respective rows of nozzles based on the print speed and the print resolution, sending first dot data for each main row portion and second dot data for each drop row portion to the printhead module; and firing nozzles from the main row portions and the drop row portions in a predetermined order. Each drop row portion is fired independently of its corresponding main row portion and is delayed relative to its corresponding main row portion by the predetermined delay.

The invention relates to the technical field of environment monitoring, in particular to a multi-point automatic water sampling device for an unmanned aerial vehicle, which comprises a water sampling mechanism arranged at the bottom of the unmanned aerial vehicle, the water sampling mechanism can be automatically connected with a flying platform of the unmanned aerial vehicle, the water sampling mechanism comprises a shell, a water tank and a water pumping component, the water tank is arranged at the bottom outside the shell, and a plurality of water sampling bins are arranged in the water tank in a surrounding manner; the shell is provided with a liquid inlet hole communicated with the water sampling bin; the water pumping component comprises a water pump, a turntable and a switching pipe, and a water inlet pipe is arranged at the suction end of the water pump and provided with a water sampling pipe; a drain pipe is arranged at the discharge end of the water pump; the turntable is driven by a switching motor and is provided with a through drainage hole, one end of the switching pipe is communicated with one end, far away from the water pump, of the drainage pipe through a sealing universal joint, and the other end of the switching pipe is communicated with the drainage hole. According to the invention, single-pass flight is realized, multi-point sample collection, storage, diversion and export can be completed, the water collection efficiency is improved, and the real-time performance of seawater monitoring is ensured.

An optical measurement system can improve the accuracy of its estimates of distances to surrounding objects by improving various aspects of its data path. Spatial resolution can be improved by subdividing histogram bins or integration registers based on spatial orientation. Saturation at any point in the data path can be detected and used to stop counting photons in individual pixels, which can then be normalized after the end of the measurement. Multiple peaks can be detected using a recursive or iterative technique to identify the largest remaining peak at each stage. Instead of iterating through the histogram memory multiple times, thresholds can be precomputed based on an estimated ambient noise level, and peaks can be detected in a single pass.

This application discloses an optical and electrical composite cable designed for simultaneous installation within pipelines, along with its processing and installation methods. By providing a composite cable with a thin wall and compact overall size, it allows the commercially available thin pipelines ranging from 6 mm to 13 mm in diameter to accommodate both optical and electrical cables in a single pass. This design reduces the amount of pipeline material needed and shortens installation time, while broadening the potential applications for these types of pipelines and improving their utilization. Since the optical and electrical composite cable is installed within a pipeline, it does not require self-supporting overhead structure, which simplifies its design. The thinner optical cable is connected to the thicker electrical cable, allowing the electrical cable to provide necessary tensile strength to the optical cable. This simplified approach to tensile strength ensures that the composite cable meets required strength standards despite its smaller size.

The present invention is a lawn maintenance machine capable of aerating, slicing, spiking, and depositing seeds all within a single pass. The present invention is an adaptor system for adapting a pre-existing system so as to enable the current devices to be capable of aerating, slicing, spiking, and depositing seeds all within a single pass. Another aspect of the current invention is a method for adapting a currently existing system so as to be capable of aerating, slicing, spiking and depositing seeds all within a single pass. Another aspect of the present invention is a riding aerator with slicer, spiker, seeder, and spreader.

1. The name of the design product: new nissan nimble welding robot system graphical interface of electronic equipment. 2. The use of the design product: an electronic device. 3. The design features of the design product: the graphical user interface. 4. The picture or photo that best shows the design features: front view. 5. The use of the graphical user interface: the staff controls the robot for welding by setting up the system. 6. The human-computer interaction mode of the graphical user interface: in the main view, enter the username and password, click the "login" icon option at the bottom of the interface, and the interface jumps to the "home page-single pass straight line" interface shown in interface change state diagram 1; in interface change state diagram 1, click the "arc" icon at the top right of the interface, and the interface jumps to the "home page-single pass arc" shown in interface change state diagram 2; in interface change state diagram 2, click the "straight line segmentation" icon at the top right of the interface, and the interface jumps to the "home page-single pass straight line segmentation" shown in interface change state diagram 3; in interface change state diagram 3, click the "standard multi-pass welding" icon on the left, and the interface jumps to the "home page-standard multi-pass welding" shown in interface change state diagram 4; in interface change state diagram 4, click the "custom multi-pass welding" icon on the left, and the interface jumps to the "home page-custom multi-layer multi-pass welding" shown in interface change state diagram 5; in interface change state diagram 5, click the "simulation" icon below, and the interface jumps to the "simulation page" shown in interface change state diagram 6; in interface change state diagram 6, click the "welding" icon below, and the interface jumps to the "welding page" shown in interface change state diagram 7; in interface change state diagram 7, click the " 》 " icon in the middle on the left, and the interface jumps to the interface shown in interface change state diagram 8; in interface change state diagram 8, click the "manual" icon, and the interface jumps to the interface shown in interface change state diagram 9; in interface change state diagram 9, click the gray blank area to return to the home page, click "configure" below, click the "machine posture" icon above, and the interface jumps to the "settings-robot posture" shown in interface change state diagram 10; in interface change state diagram 10, click the "welding gun coordinates" icon above, and the interface jumps to the "settings-welding gun coordinates" shown in interface change state diagram 11; in interface change state diagram 11, click the "process parameters" icon above, and the interface jumps to the "settings-welding process parameters" shown in interface change state diagram 12. 7. Other circumstances that need to be explained: all the background patterns, names, and numbers in the interface are variable or content pictures.

The invention provides an RDMA congestion control method and system, and the method comprises the steps: enabling a light-weight sensing end to only carry out the simple request sending and rate adjustment through concentrating the core calculation and decision-making functions of congestion control at a receiving end with rich resources for unified execution; therefore, the control logic deployment dilemma caused by topology asymmetry is fundamentally overcome, the occupation of calculation and memory resources of the sensing end is remarkably reduced, the resource advantages of the receiving end are fully played, the macroscopic appointment allocation of the network bandwidth and the microcosmic dynamic adjustment and optimization based on the real-time one-way delay are realized, and the real-time performance of the network bandwidth is improved. And finally, the transmission effects of high bandwidth utilization rate, low transmission delay and rapid convergence are achieved in the edge computing platform.

An ohmic heater for the heating of a conductive fluid is comprised of a number of selectable electrodes, arrayed in such a way as to form a single pass-through from inlet to outlet. A series of flow conduits are provided to direct the flow across the faces of adjacent electrodes. The flow conduits are further configured such that the flow path makes multiple passes across the same adjacent set of electrode faces.

The invention relates to a multi-channel shunting type industrial waste gas microbiological degradation device, which adopts a double-biological deodorization box shunting structure, is matched with a mechanical control device to link a first valve and two second valves, can flexibly switch a two-way working form and a single-way working form, and has the following three core advantages: 1, the treatment continuity is ensured; during microbial attenuation complementary cultivation and maintenance of the box body on one side, a single-pass mode is switched to start the box body on the other side, the whole machine does not need to be shut down, a bacterial liquid complementary cultivation window period does not need to be filled, and all-weather uninterrupted deodorization is achieved; 2, the device adapts to working condition fluctuation, a single-pass mode is started for low-concentration waste gas, the double centrifugal fans intensively extract air, speed and efficiency are increased, and invalid staying is reduced; a double-pass mode is started for high-concentration waste gas, double boxes are connected in parallel to expand flux, and full degradation of the waste gas is ensured; the mechanical control device achieves synchronous opening and closing of the valve and one-key mode switching, flow can be rapidly adjusted according to flora activity and waste gas concentration, the degradation working condition is stabilized, and the operation and maintenance efficiency is improved.

The invention relates to a method for preparing high-purity germanium through reduction of hydrogen and germanium tetrachloride, and belongs to the technical field of high-purity metal material preparation. The method comprises the following steps: introducing vaporized germanium tetrachloride and preheated hydrogen from the top of a vertical quartz reaction tube, and mixing; the mixed gas downwards passes through a reaction zone, a concentric quartz ring tube bundle is arranged in the reaction zone, and the reaction zone is divided into an upper high-temperature reaction zone (1000-1150 DEG C), a middle medium-temperature deposition zone (600-850 DEG C) and a lower high-temperature melting zone (940-1000 DEG C) in the gas flow direction; gaseous germanium is condensed in the ring tube bundle in the middle deposition area to form solid germanium, and the solid germanium grows downwards to the lower melting area to be melted into liquid to drop and be collected; and treating the tail gas to recover germanium tetrachloride and hydrogen for recycling. Through the design of the annular tube bundle carrier and the temperature field, the deposition-melting dynamic process is achieved, reaction balance is broken, and the conversion per pass of germanium tetrachloride is increased to 70% or above.

The present disclosure provides high viscosity ultrafiltration / diafiltration (UF / DF) and single pass tangential flow filtration (SPTFF) processes for the purification of polypeptides. A method for purifying a polypeptide from a polypeptide preparation can include the following steps in sequence: a) subjecting the polypeptide preparation to one or more purification processes and recovering a first resulting pool having a viscosity of about 5 to 40 cP; and b) subjecting the pool recovered from step a) to an SPTFF operation and recovering a second resulting pool having an operating viscosity of about 41 to 400 cP, the SPTFF operation comprising the use of membranes in either or both of a tandem membrane configuration and / or a parallel membrane configuration, where i) the operating temperature is about 15 to 55 DEG C, and ii) the feed flux is about 5 to 50 L / m2 / hr (LMH).

The invention relates to a computer architecture for verifying image frame and image line data in a single pass. Aspects of this technical solution may increase the processing speed of low latency applications while maintaining the integrity of error correction detection at these higher speeds. For example, in an image processing environment associated with autonomous navigation (e.g., driving), a large amount of image data is to be quickly and accurately processed to maintain a reliable and latest model of the physical environment. Accordingly, embodiments according to the present disclosure may provide high-speed and accurate error correction of input frame data beyond the ability to be implemented by CPU processing or general GPU processing.

To provide a highly efficient narrow groove two-electrode large heat input submerged arc welding method which can obtain a sound weld part having no high-temperature cracking and weld defects, prevents generation of a pop mark and a projection, and can obtain excellent welding workability and excellent mechanical properties of weld metal.SOLUTION: A narrow groove two-electrode large heat input submerged arc welding method of single pass per layer brings a backing material into contact with a rear face of a narrow groove having plate thickness of 60 mm or more, a chevron type or a V shape, a groove angle of 16 to 20°, and a root gap of 4 to 10 mm, and then performs submerged arc welding of single pass per layer so that the total of heat inputs of a preceding electrode and a succeeding electrode for each path is 200 to 490 kJ / cm, using a sintered type flux containing the total of SiO2 and CaO conversion values and the total of MgO of 30 to 40%, 4 to 10% TiO2, 16 to 26% Al2O3, 1 to 5% ZrO2, the total of CaF2, B2O3, Si and Al of 1.5 to 5.5%, the total of an Li2O conversion value of 0.5 to 2.0%, 15 to 25% Fe, and the total of Mn, Ni and Mo of 3.5 to 7.5%.SELECTED DRAWING: Figure 1

The invention relates to the technical field of sputter coating, and discloses PVD magnetron sputter coating equipment for a heterojunction solar cell, the PVD magnetron sputter coating equipment for the heterojunction solar cell comprises a sealing shell, a loading cavity and an unloading cavity are arranged at the top end in the sealing shell, and transfer cavities are arranged below the loading cavity and the unloading cavity; and a pretreatment cavity, a deposition cavity and a cooling cavity are arranged between the transfer cavities. Through integrated continuous conveying and double-sided asynchronous sputtering design, front and back differentiated coating can be completed through single pass of a silicon wafer, the problems of pollution and damage caused by wafer turning in a traditional process are thoroughly solved, a magnetic field is dynamically modulated through a programmable multi-pole electromagnetic assembly, active uniformity compensation of performance is achieved, and the production efficiency is improved. Under the assistance of a linear ion source, the ITO thin film with high deposition rate and high quality is obtained through the low-temperature sputtering process, and the productivity and the yield are improved.

The present application belongs to the field of lithium battery winding, and particularly relates to a lithium battery winding process equipment, which comprises a ring cylinder, a ring sleeve B, a support, a bottom plate, a motor A, a circular tube, a motor B, a suction and mixing mechanism, a motor D, a feeding mechanism and an electric push rod A. The annular area of the ring cylinder which is suspended by a support leg is divided into several circumferentially uniformly distributed fan-shaped storage spaces. A fan-shaped bottom plate which changes the storage height and is synchronously driven by the motor A is vertically and sealingly slid in each fan-shaped space. The suction and mixing mechanism which is communicated with a post-processing equipment with a negative pressure function fully mixes the powder and the ingredients filled in the several spaces separated by the partition in the ring cylinder in a single pass. The powder and the ingredients do not need to be reciprocatingly and cyclically stirred, the stirring period is shortened, and the stirring efficiency is improved.

A method for preparing a magnesium alloy tissue engineering scaffold with a smooth inner surface by laser powder bed fusion (LPBF) is provided. The method includes: step S1: scanning a porous scaffold, and selecting the densest filling scan parameters, where the scanning includes a single-pass contour scan and a single-pass filling scan; step S2: optimizing a contour scan strategy according to the densest filling scan parameters; step S3: acquiring a corresponding melt pool dimension, and adjusting a spot compensation value based on the optimized contour scan strategy; and step S4: preparing a magnesium alloy tissue engineering scaffold based on the contour scan strategy and the adjusted spot compensation value. The method eliminates powder adhesion and sagging defects inside the complex porous structure that severely affect inner surface roughness and scaffold performance, thereby the pore connection, fatigue and corrosion resistance will be improved greatly.