Abstract: The apparatus includes: a producing unit that generates ultrafine bubbles in a liquid supplied from a liquid introducing unit to produce an ultrafine bubble-containing liquid containing the ultrafine bubbles, and delivers the ultrafine bubble-containing liquid; a liquid delivering unit that delivers the ultrafine bubble-containing liquid to an outside; a buffer tank that receives the liquid delivered from the producing unit and delivers the liquid to the liquid delivering unit; and a controller that controls the delivery of the ultrafine bubble-containing liquid from the buffer tank to the liquid delivering unit such that, if the producing unit stops operating, an ultrafine bubble-containing liquid accumulated in the buffer tank is delivered to the liquid delivering unit to enable the liquid delivering unit to deliver the ultrafine bubble-containing liquid to the outside.

Abstract: The present invention provides an ultrafine bubble-containing liquid producing apparatus capable of reducing the possibility of intermitting supply of a UFB-containing liquid. An ultrafine bubble-containing liquid producing apparatus includes producing units that produce an ultrafine bubble-containing liquid containing ultrafine bubbles by using a liquid supplied from a liquid introducing unit and deliver the produced ultrafine bubble-containing liquid to a liquid delivering unit. The producing units include a plurality of ultrafine bubble generating units capable of operating independently. Each of the plurality of ultrafine bubble generating units is provided to be capable of independently switching between communicating with and being disconnected from the liquid introducing unit and the liquid delivering unit.

Abstract: An anti-agglomeration device for a nanofluid includes a support module, a motion module, a photoacoustic conversion module and a control module. The support module includes a frame and screws and is configured to support the photoacoustic conversion module and the motion module. The photoacoustic conversion module includes a nanosecond laser, a first clamp, a lens, a silica optical fiber, a second clamp, gold nanoparticles and a container and is configured to realize photoacoustic conversion to generate ultrasonic waves. The motion module includes a servo motor, a dovetailed rail, a guide screw, a fixed plate, a slider and a deep groove ball bearing. The motion module is configured to support the photoacoustic conversion module and realize the combined motions of the photoacoustic conversion module. The control module includes a support plate and a CCD camera and is configured to control the motion module in real time.

Abstract: In order to efficiently produce a liquid containing ultrafine bubbles of a desired gas, an ultrafine bubble-containing liquid producing apparatus includes a gas dissolving unit that dissolves a predetermined gas into a liquid, and a UFB generating unit that generates ultrafine bubbles in the liquid in which the predetermined gas is dissolved. A CPU performs control under a first condition in a case of causing the gas dissolving unit to operate in a circulation route passing through the dissolving unit. The CPU performs control under a second condition different from the first condition in a case of causing the UFB generating unit to operate in a circulation route passing through the UFB generating unit.

Abstract: Provided are an enclosed stirrer using intermittent resonance and a method. The enclosed stirrer comprises: two pairs of parallel tension springs (1), a fixing bracket (2), an elastic cantilever beam (3), a cantilever beam pressure clamping device (6), an eccentric motor (4), an arc-shaped cushion block (5), and an enclosed container (8). The enclosed container (8) is mounted on the fixing bracket (2) by the tension spring (1). The elastic cantilever beam (3) is installed below the enclosed container (8) and is axially parallel to the enclosed container (8). One end of the elastic cantilever beam (3) is mounted on the fixing bracket (2) as a clamping end, the other end of the elastic cantilever beam (3) is connected to the eccentric motor (4) as a movable end. The arc-shaped cushion block (5) is connected above the eccentric motor (4). The arc-shaped cushion block (5) reciprocally strikes the bottom of the enclosed container (8) during operation of the eccentric motor (4).

Abstract: An agitator for disposition within a cavity of a vessel body containing a particulate includes a weighted portion and a stirring portion. The agitator is positioned and disposed relative to the vessel body to move the stirring portion through the particulate in response to movement of the weighted portion in response to gravitational and/or inertial forces acting on the weighted portion due to movement of the vessel body. Particulate storage vessel arrangements and methods of particulate mixing are also described.

Abstract: A mixing and dispensing system for a two-component material, such as a bone cement, the mixing and dispensing system including a handle connected to the mixer via a mixing shaft. The mixing shaft extends through the piston from the piston driving end in the direction of the outlet end in order to move the mixer in dependence on movements initiated via the handle, and with the handle being detachable, in particular in a non-destructive manner, from the mixing shaft via a connector.

Abstract: A microfluidic mixing device comprising two bellows pumps (105, 115), microfluidic cartridges comprising the same and methods for use of the same are provided. The disclosed device enables efficient mixing of samples at the microfluidic scale.

Abstract: Disclosed herein are powder mixing apparatuses and methods that utilize the deagglomerizing and mixing effects of an air flow that impacts a flowing powder. The resulting powder can have smaller particle sizes and/or exhibit a more homogenous mixture than the premixed powder.

Abstract: The present invention: continuously measures pressure in real time by means of pressure detection sensors inside a vessel and inside chemical piping and quickly discharges air when abnormal pressure is generated, so as to stably supply a crude liquid through a fixed pressure-maintaining liquid supply part; checks a standard concentration after the crude liquid is mixed so as to re-transfer the mixed liquid to a mixing tank unit when the concentration thereof does not reach the reference concentration, thereby spraying the mixed liquid through a jet nozzle member; and shortens the mixing time of primarily mixed liquid so as to enable the mixed liquid to be mass-produced and a stable quality thereof to be ensured.

Abstract: A reactor for nanoparticle production comprising a main chamber including a first nozzle to which raw material gas is supplied, a lens housing connected to the main chamber in a fluidly movable manner and including a second nozzle for supplying flushing gas to the lens housing, a lens mounted on the lens housing, a light source for irradiating a laser, which passes through the lens to reach the raw material gas in the main chamber, and a hood for discharging nanoparticles generated in the main chamber. A cross-sectional area of at least a part of the lens housing decreases along a direction facing the main chamber.

Abstract: A movable device for filling one or more chambers with solid particles in the divided state, the device includes a movable frame, metering means for metering the solid particles comprising two or more metering plates comprising one or more perforations, the metering plates being arranged on top of one another such that the perforation or perforations of one metering plate is/are in connection with the perforation or perforations of the metering plate situated below and/or above it, so as to form one or more metering columns intended to be placed in connection with the chamber or chambers, means for simultaneously releasing the solid particles from the metering means to the chamber or chambers, a storage tank for storing the solid particles, which comprises a bottom pierced with through-holes that are connected with, or can be placed in connection with, the metering column or columns, and comprising unloading means for releasing the solid particles from the storage tank to the metering column or columns.

Abstract: A feed injector may have a body having an outer wall and an inner wall with a first conduit formed between the outer wall and the inner wall. The first conduit is configured to receive a atomizing gas. Additionally, a second conduit may be formed by the inner wall, and the second conduit is configured to receive a liquid. The first conduit and the second conduit are separated by the inner wall. Further, a mixing chamber may be provided at an outlet of the first conduit and an outlet of the second conduit. The atomizing gas from the first conduit and the liquid from the second conduit hit and/or mix together in the mixing chamber to form liquid droplets and a mixture of the atomizing gas and the liquid. Furthermore, a flow cone may have a first end in the second conduit and a second end in the mixing chamber.

Abstract: Provided are: a flow channel structure with which lipid particles or micelles, which are useful as nano-sized carriers, for example, in drug delivery systems, are produced with good control of particle size; and a method for forming lipid particles or micelles using the same. Said flow channel structure has a two-dimensional structure such as one in which multiple structural elements (baffles) of a specified width are alternately disposed from the two side faces in a micro-sized flow channel through which feedstock solutions are flowed.

Abstract: Described herein is a new process for the preparation of core-shell microcapsules. Microcapsules are also described herein Perfuming compositions and consumer products including said capsules, in particular perfumed consumer products in the form of home care or personal care products, are also described herein.

Abstract: A device for generating hydrogen gas having two or more storages, each storage storing a reactant or mix of reactants, and each storage coupled to a means of injecting the stored reactant or mix of reactants into a reaction chamber in a controlled manner and at an optimum rate, so that a chemical reaction occurs in the reaction chamber that produces hydrogen gas efficiently.

Abstract: The invention relates to a method for determining production parameters (1) for the production of a polymeric product, wherein a prediction model (7) is provided for calculating production parameters (1) based on polymeric product properties (4) on a computer system, which production parameters (1) comprise formulation portions (2) specifying raw material portions for polymeric production and comprise processing parameters (3) specifying process properties during polymeric production, wherein user input is provided to the computer system, which user input comprises user product parameter targets (5) specifying polymeric product properties (4), wherein the computer system applies the user product parameter targets (5) to the prediction model to calculate resultant production parameters (11) for the production of a polymeric product associated with the user product parameter targets (5). The invention also relates to a corresponding computer system.

Abstract: The present disclosure relates to systems and methods for the amplification of nucleic acids, including, but not limited to, the amplification of nucleic acid libraries and whole genome amplification.

Abstract: Devices for the manufacturing of high-quality building blocks, such as oligonucleotides, are described herein. Nano-scale devices allow for selective control over reaction conditions. Further, methods and devices described herein allow for the rapid construction of large libraries of highly accurate nucleic acids.

Abstract: A composite sorbent composition comprising a polymeric adsorbent; and an extractant having the formula, or a hydrate thereof, wherein Z is —C(O)— or —C(R?)(R?)— wherein R? and R? are each hydroxyl; and R1, R2, R3, and R4 are each independently hydrogen, halogen, hydroxyl, cyano, nitro, amino, —C(O)H, —C(O)OH, —C(O)NH2, alkyl, alkenyl, alkynyl, alkoxy, alkanoyl, alkylamino, alkyl carboxamide, alkyl ester, heteroalkyl, haloalkyl, haloalkoxy, cycloalkyl, aryl, arylalkyl, aryloxy, heterocycloalkyl, heteroaryl, heteroaryloxy, or heteroarylalkyl, each of which R1, R2, R3, and R4 is unsubstituted or substituted with one or more substituents independently chosen from halogen, hydroxyl, WO 2019/023355 A1 cyano, nitro, sulphonato, amino, —C(O)H, —C(O)OH, —C(O)NH2, alkyl, alkoxy, alkylamino, heteroalkyl, haloalkyl, haloalkoxy, cycloalkyl, aryl, arylalkyl, aryloxy, heterocycloalkyl, heteroaryl, heteroaryloxy, or heteroarylalkyl; or R1 and R2, R2 and R3, or R3 and R4 are together a group —O—CH2—O—, a group —CH2—O—CH2—, or

Abstract: Disclosed herein are polycationic microfibers comprising a high-aspect-ratio polymeric core, the polymeric core comprising a blend of a first core polymer and a second core polymer, and a polycationic polymer immobilized on the surface of the polymeric core. The polycationic microfibers are capable of sequestering or clearing nucleic acids, proteins, biomolecular complexes, exosomes, or microparticles from solutions and samples and may be formed into filters or integrated into filtration apparatuses. Also disclosed are methods for sequestering or clearing solutes from solutions and fluids, methods for the treatment of diseases or conditions, and methods for the prevention of diseases or conditions.

Abstract: A composite sorbent composition comprising a polymeric adsorbent; and an extractant having the formula (I), or hydrate in thereof, wherein X is O or S, A1 and A2 are each independently —C(O)— or —C(R?)(R?)— wherein R?, and R? are each independently hydrogen, halogen, hydroxyl, cyano, nitro, amino, —CHO, —COOH, C1-12 alkyl, C1-4 alkoxy, C1-4 alkylamino, C1-2 haloalkyl, C1-2 haloalkoxy, C1-12 cycloalkyl, C6-12 aryl, C7-13 arylalkyl, C3-12 heteroaryl, C1-12 heteroalkyl, or C4-12 heteroarylalkyl, Z is a covalent bond, —S—, —O—, —SO2—, —SO—, —P(R)(?O)—, —NR—, -C(O)-, -C(O)NH-, —C(?N—R)—, or —C(R?)(R?)— wherein R, R?, and R? are each independently hydrogen, halogen, hydroxyl, cyano, nitro, amino, —CHO, —COOH, —C(O)NH2, C1-12 alkyl, C1-12 alkoxy, C1-12 alkylamino, C1-4 haloalkyl, C1-4 haloalkoxy, C4-12 cycloalkyl, C6-12 aryl, C7-13 arylalkyl, C3-12 heterocycloalkyl, C3-12 heteroaryl, C1-12 heteroalkyl, or C4-12 heteroarylalkyl, and R1 and R2 are each independently hydrogen, halogen, hydroxyl, cyano, nitro, amino, or

Abstract: Methods of preparing titanated silica catalysts, and titanated silica catalysts. The titanated silica catalysts may include a silica support, which may include spherical beads. Methods of olefin epoxidation, which may include contacting an olefin with a titanated silica catalyst in the presence of an oxidant.

Abstract: Methods of preparing titanated silica catalysts and titanated silica catalysts are presented. The titanated silica catalysts may include a silica support, which may include spherical beads. The spherical silica beads may have an average diameter of about 0.1 mm to about 5 mm Methods of olefin epoxidation, which may include contacting an olefin with a titanated silica catalyst in the presence of an oxidant.

Abstract: A method of forming a fuel cell catalyst system, the method includes providing an anticorrosive, conductive catalyst support material having oxygen vacancies and a formula (I): MgTi2O5-???(I), where ? is any number between 0 and 3 optionally including a fractional part denoting the oxygen vacancies, coating the catalyst support material with a polymeric film, attaching a catalyst material onto the polymeric film, removing the polymeric film, and providing additional material onto the support material to increase physical, electrical, and/or mechanical contact between the catalyst material and the catalyst support material.

Abstract: A method for preparing catalyst particles that includes providing a catalyst starting material, an ion beam, and an electrostatic charge reduction device selected from a source of UV light, a source of X-rays, an electron beam, and an electrically grounded catalytic starting material carrier. The method further includes implanting the catalyst starting material with an ion beam dose primarily made of monocharged or monocharged and multicharged ions with an energy of the monocharged ions in the ion beam from at least 10 keV to at most 100 keV thereby obtaining a catalyst. The obtained catalyst particles particles are useful in NOx, CO, and/or HC emission reduction devices, fuel cells, or catalysts in chemical reactions.

Abstract: A method is provided for producing a coating layer for an exhaust gas purification catalyst device that can inhibit detachment of the coating layer when the coating layer is formed on the exhaust gas purification catalyst device. The method comprises covering a substrate with a slurry that comprises carrier particles and a dispersing medium, to form a slurry layer on the substrate, and drying and firing the slurry layer to form a coating layer, wherein the carrier particles have a median diameter (D50) of 4.00 ?m or smaller, the dispersing medium comprises water and a water-soluble alcohol, and the amount of the water-soluble alcohol in the slurry is 0.50 mass % to 12.00 mass % with respect to the slurry.

Abstract: A process for dehydrogenating alkane or alkylaromatic compounds comprising contacting the given compound and a dehydrogenation catalyst in a fluidized bed. The dehydrogenation catalyst is prepared from an at least partially deactivated platinum/gallium catalyst on an alumina-based support that is reconstituted by impregnating it with a platinum salt solution, then calcining it at a temperature from 400° C. to 1000° C., under conditions such that it has a platinum content ranging from 1 to 500 ppm, based on weight of catalyst; a gallium content ranging from 0.2 to 2.0 wt %; and a platinum to gallium ratio ranging from 1:20,000 to 1:4. It also has a Pt retention that is equal to or greater than that of a fresh catalyst being used in a same or similar catalytic process.

Abstract: A catalyst for catalytic oxidation of furfural to prepare maleic acid is composed of a carbon nitride doped with a potassium salt. A method for preparing the catalyst includes mixing the potassium salt, a precursor of the carbon nitride and a solvent to obtain a mixture, and drying and calcining the mixture to obtain the catalyst. A use of the catalyst in catalytic oxidation of furfural to prepare maleic acid, wherein the maleic acid is prepared by the step of oxidizing furfural in a solvent in the presence of the catalyst. The invention has the advantages that by using the method provided by the invention to prepare maleic acid, the conversion rate of furfural can be 99% or more and the yield of maleic acid can be up to 70.40%.

Abstract: The present disclosure is directed to novel germanosilicate compositions and methods of producing and using the same. Included among the new materials are the new germanosilicates of CIT-5 topology having Si:Ge ratios either in a range of from 3.8 to 5.4 or from 30 to 200, with and without added metal oxides. The disclosure also describes methods of preparing and using these new germanosilicate compositions as well as the compositions themselves.

Abstract: The present disclosure is directed to novel germanosilicate compositions and methods of producing and using the same. In particular, this disclosure describes new germanosilicates of CIT-14 topology. The disclosure also describes methods of preparing and using these new germanosilicate compositions as well as the compositions themselves.

Abstract: A novel catalyst composition and its use in the oligomerization reaction converting a portion of a C2 to C5+ alkene feed stream to C4 to C6+ olefin derivatives. The catalyst comprises a Group VIII noble metal selected from the group consisting of nickel, iron, cobalt, and combinations thereof, on a support. The support can be silica, silicon dioxide, titanium dioxide, metal modified silica, silica-pillared clays, silica-pillared micas, metal oxide modified silica-pillared mica, silica-pillared tetrasilicic mica, silica-pillared taeniolite, zeolite, molecular sieve, and combinations thereof. The catalyst composition is an active and selective catalyst for the catalytic oligomerization of alkenes to olefins and olefin derivatives.

Abstract: Disclosed are a catalyst and a preparation method therefor, the catalyst being able to maintain a high production yield of C8 aromatic hydrocarbons in the process of converting a feedstock containing alkyl aromatics to C8 aromatic hydrocarbons such as mixed xylene through disproportionation/transalkylation/dealkylation while reducing a content of ethylbenzene in the products.

Abstract: A method for C—H bond activation and/or C—N coupling reaction comprises using a metal catalyst to catalyze the C—H bond activation and/or C—N coupling reaction; wherein the metal catalyst represented by the following formula a metal catalyst for C—H bond activation and/or C—N coupling reaction, and a method using the same and application thereof. Specifically, a metal catalyst represented by the following formula: wherein Q is a 5 or 6 membered aromatic ring; W, X, and Y are the same or different, and are independently N, S, P, or O; M is Ni, Pd, Fe, Co, Cr, Mn, Cu, Pt, Ir, or Ru; Z is halide (F, Cl, Br, or I), acetate, water, or hydroxyl; R1 and R2 are the same or different, and are independently alkyl, aryl, alkylaryl or cycloalkyl.

Abstract: A hydroformylation catalyst having excellent catalytic activity and stability, a composition including the hydroformylation catalyst, and a method of preparing an aldehyde using the hydroformylation catalyst, wherein, when hydroformylation of an olefin compound is performed in the presence of the hydroformylation catalyst to prepare an aldehyde, the normal/iso (n/i) ratio of the prepared aldehyde is lowered, and synthesis gas yield is increased.

Abstract: The invention relates to oligomerization of olefins, such as ethylene, to higher olefins, such as a mixture of 1-hexene and 1-octene, using a catalyst system that comprises a) a source of chromium b) one or more activators and c) a phosphacycle-containing ligating compound. Additionally, the invention relates to a phosphacycle-containing ligating compound and a process for making said compound.

Abstract: A metal trap for an FCC catalyst include pre-formed microspheres impregnated with a salt of calcium and/or magnesium and an organic acid salt of a rare earth element.

Abstract: Systems and methods for production of externally-pore-blocked, internally-pore-opened modified zeolite crystals, the method including mixing zeolite crystals with an organic pore blocking agent; heating the zeolite crystals mixed with the organic pore blocking agent to block internal pores of the zeolite crystals and produce internally-pore-blocked zeolite crystals; mixing the internally-pore-blocked zeolite crystals with an external pore blocking agent; and calcining the internally-pore-blocked zeolite crystals mixed with the external pore blocking agent, to re-open internal pores via decomposition of the organic pore blocking agent and to block external pores via formation of a silica layer over external pores of the zeolite crystals, forming the externally-pore-blocked, internally-pore-opened modified zeolite crystals.

Abstract: An ion exchange chromatography column contains an ion exchange stationary phase that includes a charged substrate, a plurality of first particles, and a plurality of second particles. The plurality of first particles each include first ion exchange groups and the first particles are ionically bound to the charged substrate. The plurality of second particles each include second ion exchange groups and the second particles are ionically bound to the charged substrate. The first particles having a first ion exchange group density, and the second particles having a second ion exchange group density. The first ion exchange group density is greater than the second ion exchange group density. The ion exchange chromatography column has a number of zones connected in series where each zone can have a varying level of first ion exchange groups and second ion exchange group from the inlet zone to the outlet zone.

Abstract: A system for performing a chemical and/or biological process has a pipette for processing material used in the process. The pipette can have a tip that can pierce a sealing material of a chamber and then be placed in contact with the bottom surface of the chamber that is housing a material used in the process. The tip has a plurality of passageways with openings located along the outer perimeter of the tip. The placement of the openings at the outer perimeter permits the tip to be placed on the bottom surface of a chamber such that most of the material in the chamber can be extracted by the pipette. In addition, the placement of the tip on the bottom surface of the chamber with openings along the outer perimeter of the tip permits the pipette to agitate existing material in the chamber when the pipette is providing additional material into the chamber.

Abstract: A chip for sample analysis is provided. The chip for sample analysis according to an embodiment of the present application includes a sample storage unit, a capture path configured to capture an analyte contained in a sample and communicating with the sample storage unit, a washing solution storage unit communicating with the capture path and a delay unit included between the capture path and the washing solution storage unit such that a washing solution flowing from the washing solution storage unit to the capture path passes through. When the chip is rotated for sample analysis, the delay unit may be configured to delay the passage of the washing solution introduced from the washing solution storage unit such that the washing solution reaches the capture path later than the sample.

Abstract: According to one embodiment, a liquid medicine discharge device includes a nozzle plate including a nozzle from which a liquid medicine can be discharged, a pressure chamber structure having an outlet on a first surface side and an inlet on a second surface side and a pressure chamber in fluid communication with the nozzle via the outlet on the first side, a liquid holding container on the second surface and in fluid communication with the pressure chamber via the inlet on the second surface, and an actuator configured to cause the liquid medicine to be ejected from the nozzle by changing a pressure in the pressure chamber and including a piezoelectric element formed of a lead-free material.

Abstract: In some forms, the present disclosure provides systems and methods for isolation of platelet rich plasma from a liquid tissue sample. In accordance with some forms of the disclosed systems and methods, provide rapid separation of blood components with the need for centrifugation. Accordingly, in one embodiment, the present disclosure provides a method for isolating platelet rich plasma, the method comprising combining a liquid tissue sample with a polymer composition, the polymer composition comprising polyethylene glycol.

Abstract: Method, apparatus, and computer program product are provided for anonymized diagnosis using lateral flow assays. In some embodiments, a test card includes one or more lateral flow assay (LFA) with one or more test patterns (e.g., full line, partial line, dot), one or more dummy patterns, and one or more control patterns. To visually encode LFA results, at manufacture, one or more lines/dots containing true results of the LFA(s) each has a position mixed with other “dummy” lines/dots, in randomized position patterns selected from among a plurality of possible position patterns. An optical machine-readable representation of data (e.g., QR code) is attached to the test card and encodes test card identification information (e.g., lot number, serial number, test type) associated with the test card. In some embodiments, a passcode card having a scrapeable coating that conceals a passcode associated with the test card is removably attached to the test card.

Abstract: A reference slide and methods for making and using the same are considered. The reference slide comprises a reference section, which is an area or location of a substrate comprising one or more reference moieties. The one or more reference moieties, which represent one or more cell lines, comprise one or more distinguishable features. The distinguishable features can be the same as or different than distinguishable features of the sample or target analyte.

Abstract: An hourglass shaped blood fractionation tube is sized and shaped such that whole blood that has been centrifuged with a density gradient medium yields a PBNC layer within the narrowed neck of the tube. This orientation results in an elongated or widened PBMC layer, versus what would result in a conventional fractionation tube. Elongating or widening the PBMC layer allows technicians to harvest higher purity and higher volume PBMC samples versus samples harvested with a standard cylindrical blood fractionation tube. The hourglass shaped blood fractionation tube according to the present invention preferably includes a cap and can be used in conventional centrifuges and robotic pipetting stations.

Abstract: The present invention relates to diagnostic kits and methods based on lateral flow assay devices for detecting the presence or quantity of one or more test analytes within a test sample taken from the skin of a mammal.

Abstract: The present disclosure relates to a sampling device for a liquid sample. The sampling device can comprise a main case and a sample transfer member that can be configured in a sample acquisition configuration and in a sample transfer configuration.

Abstract: Disclosed herein is a lateral flow test arrangement suitable for detection of an analyte in saliva. The arrangement can comprise a carrier and a sequence of different polymeric pads arranged on said carrier, wherein said sequence of polymeric pads comprises in flow direction.

Abstract: A patterning method of a film is disclosed. The method including: providing a film including a first surface; forming n etching barrier layers on the first surface of the film, and n is an integer larger than or equal to 2; and performing n etching processes on the film to form a recessed structure on the first surface using the n etching barrier layers as masks, the recessed structure includes n bottom surfaces respectively having different depths. Two adjacent etching processes of the n etching processes include a previous etching process and a subsequent etching process, and after the previous etching process is completed, a part of the n etching barrier layers is removed to form a mask for the subsequent etching process; a material of the part of the n etching barrier layers which is removed is different from a material of the mask of the subsequent etching process.