627 results about "Pulse electric field" patented technology

The invention discloses a flocculation treatment device and method for removing high turbidity of a water sample. The method comprises the following steps: monitoring an inflow turbidity parameter in real time, continuously collecting original optical characteristic data of water through an optical sensor array, and calculating a turbidity fluctuation rate parameter after noise reduction treatment; carrying out graded rotational flow mixing treatment, forming a pressure gradient through three stages of tapered rotational flow pipes in sequence, activating an ultrasonic frequency field, and synchronously adding main and auxiliary flocculants; the method comprises the following steps: introducing a water sample into a multi-stage gradient flocculation reaction zone, and sequentially executing turbulent flow enhanced flocculation, slow stirring flocculation and pulsed electric field assisted flocculation to form a floc structure with different particle size distribution; running parameters of a sedimentation module are adjusted according to real-time effluent turbidity feedback, and the inclination angle of an inclined plate assembly and the opening degree of a mud discharging valve are dynamically adjusted; a parameter set is updated through a prediction model based on periodically collected system operation data, a closed-loop optimization control strategy is formed, the adaptability to extreme turbidity is enhanced, the solid-liquid separation efficiency is improved, the overall energy consumption is reduced, and the efficient and stable requirements of emergency treatment are met.

The invention belongs to the field of blood product separation, and discloses a high-efficiency chromatography system and method for blood product separation, and the system comprises an intelligent chromatography column module, an automatic sample injection and accurate flow rate control module, a chromatography filler and column design module, a real-time detection and data analysis module, and an intelligent automatic control and management module. By designing an efficient micro-nano filler chromatographic column and matching with a pulsed electric field auxiliary technology and intelligent automatic control, efficient and high-purity separation and purification of target blood product components are realized. The intelligent regulation and control module used in the invention can dynamically regulate chromatography conditions in real time, and the problems of unstable flow velocity and column pressure in the traditional method are thoroughly solved. And meanwhile, a multi-point real-time detection and feedback technology is adopted, so that the separation process is more accurate, transparent and controllable.

The invention relates to a kitchen waste oil recovery treatment method, which comprises: S1, carrying out multi-field synergistic pretreatment: sequentially carrying out ultrasonic wave and high-frequency pulse electric field treatment on waste oil to break an emulsion layer, adding magnetic nanoparticles to adsorb polar impurities, and carrying out magnetic field separation to obtain high-purity oil; s2, supercritical catalytic reaction: under the CO2 supercritical condition, using a core-shell structure composite catalyst to synchronously perform transesterification reaction and glycerol dehydration reaction; s3, dynamic membrane separation: separating biodiesel and glycerol in real time through an intelligent membrane assembly; s4, gradient utilization of energy: recovering reaction waste heat to drive membrane distillation to concentrate wastewater, and using tail gas CO2 for carbonation reaction to generate calcium carbonate. Through four core technologies of multi-field collaborative pretreatment, low-temperature supercritical catalysis, dynamic membrane separation and energy gradient utilization, triple limitations on efficiency, cost and environmental protection in the prior art are remarkably broken through.

Treatment of damaged, diseased, abnormal, obstructive, cancerous or undesired tissue (e.g. a tumor, a benign tumor, a malignant tumor, a cyst, or an area of diseased tissue, etc) is provided by delivering specialized pulsed electric field energy to target tissue areas in a specific dose so as to obtain a superior outcome. The specialized PEF energy and delivery has been optimized to provide advanced treatment of target tissue areas, including destruction of undesired tissue and generation of improved inflammatory and immune responses. The specialized PEF energy provides superior outcomes to radiofrequency ablation and irreversible electroporation.

High-frequency irreversible electroporation (H-FIRE) is a tissue ablation modality employing bursts of electrical pulses in a positive phase-interphase delay-negative phase-interpulse delay pattern. Despite accumulating evidence suggesting the significance of these delays, their effects on therapeutic outcomes from clinically-relevant H-FIRE waveforms have not been studied extensively. The present invention provides methods of pulse delivery, including delays, that mitigate bubble formation and / or minimize the risk of arcing, such as due to the presence of bubbles, and / or minimize muscle stimulation are described herein.

The invention discloses an electro-optical-acoustic cooperative partial discharge detection device and method, and belongs to the field of equipment discharge fault detection. The device integrates a high-frequency current detection module, a photoelectric coupling detection module and an acoustic emission detection module; a high-frequency pulse current signal of a cable grounding loop, a pulse electric field of an insulating surface and an ultrasonic signal in a solid medium can be collected at the same time; all the collected signals are sent to the signal integrated processing module for alignment, noise reduction and multi-signal homologous conformity test; after detection, the signal integration processing module extracts combined feature vectors from the signals and inputs the combined feature vectors to the classification discriminator; finally, the discriminator outputs the probability of partial discharge, and if the probability exceeds a preset threshold value, it is judged that partial discharge exists in the cable. Therefore, by implementing the method and the device, the problems that single-mode detection in the prior art is poor in anti-interference capability in a complex field environment, and false alarm or missing alarm is easy to occur can be solved.

Systems, devices, and methods described herein relate to catheter devices for therapy delivery. In some embodiments, a catheter device includes an expandable electrode and a needle, where the needle can be advanced distal to a distal end of the expandable electrode and inserted into a tissue site. The expandable electrode and the distal end of the needle can be configured to deliver electroporation to the tissue site.

The invention discloses a method for preparing ultra-high-purity quartz by multi-stage synergistic purification of quartz ore, and belongs to the technical field of ultra-high-purity quartz preparation. According to the method, natural quartz ore is used as a raw material, mineral impurities, lattice impurities and inclusions in quartz are deeply removed through multi-stage synergistic processes such as low-temperature plasma activation, biological leaching, supercritical CO2-assisted acid leaching, microwave-assisted chloridizing roasting and pulsed electric field enhanced acid leaching, and finally a high-purity quartz product with the SiO2 purity larger than or equal to 99.998% (4N8 grade) is obtained. According to the invention, a low-temperature plasma activation technology, microbial metallurgy, supercritical fluid extraction and a pulsed electric field strengthening technology are organically combined, so that the energy efficiency bottleneck and environmental protection limitation of a traditional high-purity quartz preparation process are broken through; the obtained quartz sand product can reach the standards of high-purity quartz sand for semiconductor quartz glass and high-purity quartz sand for photovoltaic quartz crucibles.

The invention discloses a novel electrolytic tank pipeline filter and a self-cleaning system. The novel electrolytic tank pipeline filter comprises a multi-stage filtering part, the self-cleaning system and an intelligent control system, the multi-stage filtering part comprises multi-stage filter elements arranged in the material pipeline, and the multi-stage filter elements are arranged from large to small according to the filtering particle size to form a filtering gradient; the self-cleaning system acts on the multi-stage filter element part at the same time or in a time-sharing manner on the basis of a fluid reverse recoil principle; the self-cleaning system is combined with pulsating flushing control, so that the filter element is separated from a filter cake at low loss; the multi-stage gradient filtration is adopted, impurities are efficiently and accurately intercepted, the filter elements with the particle sizes from large to small are arranged in a gradient mode, the first-stage titanium alloy filter element intercepts large particles, the second-stage polytetrafluoroethylene membrane filters tiny impurities, the efficiency is improved through graded interception, the loss of the filter elements is reduced, and the material purity and the hydrogen production quality are guaranteed. The multi-element self-cleaning technology is adopted, low-loss deep cleaning is achieved, and the self-cleaning system integrates multiple technologies such as fluid reverse backflushing, pulsating flushing, ultrasonic vibration and a pulsed electric field.

The invention relates to the technical field of pulse electric field measurement, and discloses a time drift compensation method of a pulse electric field measurement system based on model parameterization. According to the method, a parameterized model is constructed in simulation software, and the parameterized model is additionally provided with two servo zeroing compensation circuits on the basis of an original measurement system, and the two servo zeroing compensation circuits are connected to the output ends of two in-phase operational amplification circuits respectively to form a negative feedback loop used for dynamically suppressing low-frequency baseline drift; acquiring electric field time domain waveform data of the output end of the third in-phase operational amplifier circuit; calculating a transfer function of a pulsed electric field measurement system in the parameterized model, converting the transfer function from a frequency domain state to a time domain state through inverse Fourier transform, and then performing deconvolution on the transfer function of the time domain state and electric field time domain waveform data to obtain real electric field intensity; according to the invention, time drift caused by operational amplifier input imbalance, power supply fluctuation and temperature change is automatically compensated in real time, and the stability and precision of system measurement are improved.

The invention provides a duodenal mucosa adjusting system and method based on pulsed electric field ablation and application of the duodenal mucosa adjusting system and method in diabetes treatment, the duodenal mucosa adjusting system comprises an intelligent control host capable of achieving bidirectional data transmission and an adjustable catheter, and the intelligent control host initializes parameters and adjusts pulse parameters by monitoring impedance data in real time until pulses are interrupted or terminated; periodic ablation is carried out, periodic intervals are used for measuring impedance data, the ablation depth is evaluated according to the impedance change rate, and whether next section ablation is carried out or not is judged till full-area ablation is completed. The far-end ablation adopts a structure of combining fusiform flexible support and annular electrode spiral arrangement to ensure that an ablation field uniformly covers mucous membrane plica of a duodenum bulb part and a descending part; a cell selective ablation mechanism is adopted, the critical electric field intensity is set, K cell electroporation is selectively induced, and meanwhile goblet cells are protected.

The present invention discloses a method and device for determining ablation parameters for high-frequency pulse electric field ablation. The method comprises: acquiring collected medical image data containing depth information, determining a corresponding lesion box containing three-dimensional information of the lesion based on the medical image data; analyzing and segmenting the lesion box to obtain the contour and depth of the lesion and the contour of the electrode used to ablate the lesion; starting from a plurality of equally spaced points on the boundary of the electrode contour, emitting a preset number of rays to the surrounding area, obtaining the number of intersections between the rays and the lesion box to determine whether the electrode and the lesion are in contact; when the electrode and the lesion are in contact, determining the corresponding ablation parameters based on the contour and depth of the lesion, the ablation parameters including pulse voltage, pulse width, number of pulse trains, and number of discharges. The present invention solves the problem of inaccurate ablation parameter determination in the prior art.

Treatment of damaged, diseased, abnormal, obstructive, cancerous or undesired tissue (e.g. a tumor, a benign tumor, a malignant tumor, a cyst, or an area of diseased tissue, etc) is provided by delivering specialized pulsed electric field (PEF) energy to target tissue areas in a specific dose so as to obtain a superior outcome. The PEF energy and delivery has been optimized to provide advanced treatment of target tissue areas, including destruction of undesired tissue and generation of improved inflammatory and immune responses. These various types of treatment are controlled by a variety of factors including the electrode geometry, the dose of PEF energy delivered, the time the energy is delivered over, and the waveform of the PEF energy itself. The PEF energy is delivered in the form a dose which is considered to be one application of the specialized energy. Each dose creates a lesion in the target tissue area.

The invention discloses a separation and purification method of soy sauce flavor type vinasse polypeptide and application thereof, and belongs to the technical field of polypeptide separation and purification. The method comprises the following steps: S1, pretreatment: drying and crushing soy sauce flavor type vinasse, then treating by adopting a pulsed electric field cooperating with cellulase and Tween, setting the intensity of the pulsed electric field to be 1.0-1.5 kV / cm, adjusting the pulse width to be 10-20ms, keeping the frequency to be 10-15Hz, and controlling the temperature to be 20-30 DEG C; the addition amount of the cellulase is controlled to be 50-80 U / g of dry weight of the vinasse, the treatment time is 2-3 h, and meanwhile low-concentration Tween is added; s2, carrying out composite enzymolysis; s3, gradient membrane separation; and S4, dynamic ion exchange chromatography. Through cooperation of multiple physical-biological-chemical technologies, a complete technical chain for efficient separation and purification of soy sauce flavor type vinasse polypeptide is constructed.

The invention discloses an analysis method and system for energy conservation and loss reduction of transformers, and the method comprises the steps: collecting the standby state data of a transformer group, recognizing a high-loss unit, and predicting the parameter drift trend of the high-loss unit; acquiring an electromagnetic impact strength signal in a working state; the parameter drift trend and the electromagnetic impact strength signal are fused, and the collaborative imbalance risk is evaluated; and according to a risk assessment result and a risk cause, dynamic voltage regulation and load balancing optimization are adaptively executed. The cross-working-condition correlation analysis and closed-loop control are carried out on the transformer group serving as the power supply core, so that the standby no-load loss can be effectively reduced, the equipment aging can be delayed, the operation cost can be reduced, the long-term stability and reliability of the power supply system can be ensured, and the method can be widely applied to the industrial fields of pulsed electric fields, precision manufacturing and the like.

The invention relates to the technical field of hygienic product manufacturing, and discloses a sanitary napkin core body based on a nano material, functional particles are accurately positioned through flow field directional regulation and control of fiber three-dimensional orientation distribution, pulsed electric field activation free radical gradient polymerization and supercritical CO2 deposition, a surface micropore compact water locking layer with the aperture of 5-20 microns is constructed, and an inner macropore flow guide layer is formed. The pore diameter is 80-150 microns, and a cross-scale synergistic structure is formed. Self-reconstruction of the fiber is excited by sudden change of the flow field rotating speed, and mutual exclusion limitation of the absorption rate and the liquid retention amount of a traditional homogeneous structure is broken through in combination with diffusion kinetics of a terahertz wave resonance reinforced cross-linking agent; a C-O-Ag chemical anchoring point is established by a plasma bonding technology, and the nano-silver particles are physically confined by a graphene oxide sheet layer, so that the problems of particle agglomeration and ion burst release in a traditional spraying process are solved. The dynamic multi-field synergistic process realizes porosity gradient, oriented arrangement of molecular chains and long-acting residence of functional particles, and provides a core solution with high absorptivity, zero reverse osmosis and long-acting bacteriostasis for hygienic products.

A multimodality or hybrid ablation system includes an ablation apparatus for creating a lesion in target tissue. The ablation apparatus has an ablation shaft including a handle, a first portion, an ablation portion, distal tip, at least one ablation energy delivery lumen, at least one ablation energy return lumen, and a stylet lumen that extends substantially along a length of the ablation shaft from the handle to at least the ablation portion. The ablation apparatus also includes a stylet that is capable of being inserted into the stylet lumen where the stylet is made of a shape-memory material. A plurality of electrodes are arranged on the ablation portion for measuring or verifying tissue contact with the tissue and applying a pulsed electric field. Optionally, the pulsed electric field may be applied after, contemporaneously, or for only a portion that the cryo-modality is applied to the target tissue.

The invention belongs to the technical field of bimetal part manufacturing, and particularly relates to a method for preparing aluminum-magnesium bimetal through a pulse electromagnetic composite field and a bimetal product, and the method comprises the following steps that a casting foam model is prepared according to the preset form of a workpiece, and a solid aluminum inlay and the casting foam model are assembled to form a composite model. And embedding the composite model into a sand box. During pouring, a pulsed magnetic field and a pulsed electric field are applied to the composite model in a vacuum environment. And cooling to obtain the aluminum-magnesium bimetal product. The invention further discloses the aluminum-magnesium bimetallic product prepared through the method. The method is suitable for manufacturing aluminum-magnesium bimetal castings with complex shapes, the process is simple, the bimetal interface is easy to control, the bimetal bonding performance is good, the alloy strengthening effect is good, grain refinement is effectively achieved, interface defects are overcome, and the method is suitable for producing various related parts in the fields of automobiles, spaceflight and the like.

The invention provides signal acquisition equipment for pulsed electric field ablation. The signal acquisition equipment comprises an input interface module, a signal conditioning circuit, a differential-to-single-ended circuit and a signal acquisition module, the input interface module comprises a first input interface and a second input interface; the signal conditioning circuit is arranged between the input interface module and the differential-to-single-ended circuit and comprises an adjustable resistance sub-circuit with an adjustable resistance value, a first end of the adjustable resistance sub-circuit is connected with the first input interface, a second end of the adjustable resistance sub-circuit is connected with the second input interface, and a sliding end of an adjustable resistor in the adjustable resistance sub-circuit is grounded; the first input end of the differential-to-single-end circuit is connected with the first end of the adjustable resistor sub-circuit, and the second input end of the differential-to-single-end circuit is connected with the second end of the adjustable resistor sub-circuit; and the signal acquisition module is connected with the output end of the differential-to-single-terminal circuit. According to the signal acquisition equipment provided by the embodiment of the invention, the accuracy of pulse signal acquisition can be improved.

The invention provides a heavy metal contaminated soil remediation method and device based on directional regulation and control of an electrode array, and the method comprises the following steps: filling heavy metal contaminated soil to be remediated into a soil chamber, and arranging the electrode array in the soil chamber; an electrolyte is added into the cathode chamber and the anode chamber respectively, so that the electrolyte enters the soil chamber, and the moisture content of the soil is maintained to be 20-50%; and under the condition that the pH value of the electrolyte in the cathode chamber and the pH value of the electrolyte in the anode chamber are maintained at 6.0-7.5, bipolar pulse electric fields are applied to the anode and the cathode, so that heavy metal ions in the heavy metal contaminated soil to be remediated are directionally migrated to the surface of the electrode array, and remediation is completed. Moreover, the remediation method and device are simple and convenient to operate, efficient, controllable and environment-friendly remediation of the heavy metal contaminated soil is achieved, good engineering applicability and economical efficiency are achieved, and the green development requirement of the soil remediation technology is met.

The invention relates to the technical field of TGV packaging, in particular to an electroplating system for a TGV and panel-level packaging process. Comprising a tank body and environment maintenance module, a soluble anode and current redistribution module, a cathode clamp and substrate posture regulation and control module, a micro-area jet flow coupling array module, a pulsed electric field and impedance compensation module and an electroplating liquid peripheral circulation and online regeneration module, the thickness uniformity of a plating layer on a panel-level large-size substrate is remarkably improved through real-time closed-loop coupling of micro-area jet flow and current density and accurate correction of an adjustable shielding grid on edge current, the thickness uniformity of the plating layer on the panel-level large-size substrate is improved, and the thickness uniformity of the plating layer on the panel-level large-size substrate is improved. According to the method, the through hole filling void rate is reduced to an extremely low level, and bubble desorption, crystal nucleus homogenization and updating of an interface solution are effectively promoted by utilizing micro-vibration, dynamic variable immersion and periodic shaking functions of the cathode clamp, so that thickening of a diffusion layer is inhibited, and the defects of through hole filling void and the like are reduced.

The invention relates to the technical field of medical equipment, in particular to a high-voltage electric field electrocardio synchronous pulse triggering method and a pulse electric field ablation system. The method comprises the following steps: in response to starting of target equipment, performing feature sampling on a target object to obtain a feature sampling signal; the feature sampling signals are processed based on a preset detection algorithm, waveform features in the electrocardiosignals are obtained, the detection algorithm is achieved based on a dynamic integral window length and a dynamic peak detection threshold value, and the dynamic integral window length and the dynamic peak detection threshold value are determined based on a basic threshold value in the associated updating period and historical feature sampling signals; determining target wave crest information in the electrocardiosignal based on the waveform characteristics, and generating a pulse driving time sequence signal matched with the target wave crest information; and driving target equipment based on the pulse driving time sequence signal to realize electrocardio synchronous pulse triggering. By adopting the method, the real-time performance, the accuracy and the stability of pulse triggering can be improved.

Example described herein include energizing techniques for ablation. In some examples, a self-sizable ablation device may include a flexible circuit including multiple segments of electrodes. Generator circuitry may individually energize electrodes of the multiple segments. The generator circuitry may utilize pulsed electric fields to control activation of selected segments of electrodes of the multiple segments of electrodes to control an amount of energy applied to the treatment region below an energy threshold for muscle stimulation. In some examples, the generator circuitry may provide pulses to segments of electrodes in a bipolar or monopolar manner. By selecting areas of ablation by selectively activating segments of electrodes in a sequence, and an amount and polarities of voltages or currents for energizing electrodes, muscle stimulation may be reduced. Examples of waveforms for use in energy delivery are described.

An improved system described herein can include an expandable member (e.g., to temporarily dilate a targeted tissue) equipped with one or more Pulsed Field Electroporation (PFE) electrodes configured to cause localized and targeted PFE output at the targeted tissue.

High-frequency irreversible electroporation (H-FIRE) is a tissue ablation modality employing bursts of electrical pulses in a positive phase-interphase delay-negative phase-interpulse delay pattern. Despite accumulating evidence suggesting the significance of these delays, their effects on therapeutic outcomes from clinically-relevant H-FIRE waveforms have not been studied extensively. The present invention provides methods of pulse delivery, including delays, that mitigate bubble formation and / or minimize the risk of arcing, such as due to the presence of bubbles, and / or minimize muscle stimulation are described herein.

The invention discloses a composite electric field catalytic oxidation synergistic oil and gas field produced water treatment method which comprises the following steps: acquiring an electric flocculation effect generated by a corrosion-resistant titanium-based coating anode and a stainless steel cathode under optimized pulsed electric field parameters through a turbidity sensor and a particle size analyzer, and superposing low-frequency pulses in a composite pulse mode, maintaining the temperature of the reactor to be 20-40 DEG C in combination with a temperature control system to obtain initial floc particle size distribution and concentration data; the concentration state of the floc in the concentration tank is monitored by adopting a conductivity sensor according to the amount of the floc in the concentration tank treatment pollution discharge scheduling scheme, the content of remaining oil drops and suspended solids is analyzed in combination with an emulsion monitoring module, and the water quality parameter change of the concentration tank is recorded through a data analysis system, so that a final water quality treatment result is determined.

Systems and methods for infection prevention and treatment in biological conduits using electroporation or pulsed field ablation (PFA). The system includes an elongate member, such as a dialysis catheter, vascular access device, or peritoneal dialysis conduit, with at least one electrode positioned along, within, or around the member. A control unit applies pulsed electric fields to inhibit microbial colonization, disrupt bacterial biofilms, and alter permeability of bacterial or endothelial cells to enhance sterility or fluid exchange. The system may use real-time impedance monitoring, microbial detection, or fluid composition analysis to adjust electroporation parameters. Electroporation may synchronize with dialysis cycles or antimicrobial lock solutions. The method includes automated, clinician-controlled, or sensor-triggered treatments to reduce infections and improve device longevity. The system provides an alternative or augment to antibiotics, reducing the risk of drug-resistant infections while improving the longevity and safety of medical implants.

Systems, devices, and methods described herein relate to catheter devices for therapy delivery. In some embodiments, a catheter device includes an expandable electrode and a needle, where the needle can be advanced distal to a distal end of the expandable electrode and inserted into a tissue site. The expandable electrode and the distal end of the needle can be configured to deliver electroporation to the tissue site.

The invention provides a microwave pulse electric field vibration synergistic fracturing and permeability increasing gas extraction promoting device and method, and relates to the technical field of low-permeability coal seam fracturing and permeability increasing. According to the method, multi-physical field coupling synergistic interaction is achieved, and the fracturing efficiency and range are greatly improved. According to the invention, deep collaboration of multiple physical fields is realized through a specific time sequence and energy ratio. The thermal stress generated by microwave preheating enables a large number of microcracks to be generated in the coal body and soften the coal quality, and the resistivity and the medium strength of the coal body are reduced. In the state, the pulsed electric field with lower voltage can preferentially and effectively break down and expand the fracture network along the micro-fracture path; meanwhile, high-frequency mechanical vibration not only efficiently transmits energy to the tip of the fracture to generate stress concentration to promote extension of the fracture, but also disturbs coal particles to promote gas desorption. Through three-field cooperation, cracks can be more efficiently initiated, expanded and communicated in a three-dimensional space, a three-dimensional complex crack network far beyond the action range of a single technology is formed, and the overall permeability of a coal seam is remarkably improved.

The invention belongs to the technical field of fruit freeze-drying processing, and particularly relates to a comprehensive fruit freeze-drying processing method capable of reducing nutrient loss of fruits, which comprises the following steps: S1, immersing sliced fruit slices into a composite color fixative, and simultaneously applying ultrasonic and pulsed electric field treatment on the composite color fixative system containing the fruit slices under the conditions that the ultrasonic power is 200-300W, the pulsed electric field intensity is 15-25kV / cm, and the ultrasonic power is 200-300W and the pulsed electric field intensity is 15-25kV / cm; the co-processing time is 2-4 minutes, so as to obtain the color-protected and strengthened fruit slices; s2, sequentially carrying out three-stage magnetic field freezing treatment on the color-protected and strengthened fruit slices to obtain frozen fruit slices; s3, dynamically adjusting parameters of the frozen fruit slices by adopting an AI algorithm, and performing vacuum freeze-drying in stages to obtain primary freeze-dried fruit slices; s4, placing the primary freeze-dried fruit slices in a vacuum environment to obtain deeply dried fruit slices; and S5, soaking the deeply dried fruit slices in an aqueous solution containing 0.5-1% of amyloid-like protein, 0.2-0.4% of sodium alginate and 0.1-0.3% of cellulose nanocrystals for 1-2 minutes to form a composite protective film with the thickness of 1-3 microns, so as to obtain the coated fruit slices.