25 results about "Dielectrophoretic force" patented technology

The invention discloses an electrically-driven integrated liquid drop microfluidic device, relates to the technical field of microfluidics, and is used for solving the technical problems that most of the existing control modes are limited to plane control and cannot adapt to unstructured working environments in a deep cavity and a biochemical analyzer. The electrically-driven integrated liquid drop microfluidic device comprises a supporting plate, a liquid collecting plate, a detection platform, a displacement mechanism and a liquid transferring mechanism, the supporting plate is provided with a first surface and a second surface which are oppositely arranged; the supporting plate is arranged on the fixed platform through the first surface; the liquid collecting plate is arranged on the supporting plate through the second surface; the detection platform is arranged at any end of the liquid collection plate; the displacement mechanism is arranged to move in the horizontal and / or vertical direction relative to the liquid collecting plate; the pipetting mechanism is arranged on the displacement mechanism and is used for moving the liquid drops or the liquid marbles from the liquid collection area to the detection platform through dielectrophoretic force.

This invention provides a microplastic particle screening and separation device and method based on photoinduced dielectrophoresis. The device comprises a photoinduced dielectrophoresis chip consisting of a first illumination region, a second illumination region, a controllable barrier block, and a microchannel layer. By applying light to different positions on the photoinduced dielectrophoresis chip, the conductivity at the illumination position changes, thereby generating a non-uniform electric field. Due to the different radii of the microplastic particles, the magnitude of the photoinduced dielectrophoretic force varies. Larger-radius microplastic particles experience a greater dielectrophoretic force and cannot pass through the illumination region, while smaller-radius microplastic particles experience a smaller dielectrophoretic force and can flow to the sample outlet. By changing the position of the controllable barrier block, the separation of microplastic particles of three different radii can be achieved. The microplastic particle screening and separation device and method based on photoinduced dielectrophoresis described in this invention can achieve the separation and screening of target microplastics of different sizes using contactless photoinduced dielectrophoresis force.

The application discloses a kind of microscale microplastic migration occurrence multi-physical field coupling simulation method, belong to ecological environment field.The method aims at solving the problem that existing microplastic migration model ignores interface adsorption process, is difficult to couple the action of multiple physical fields and is not suitable for the problem of insufficient adaptability to heterogeneous environment.Its main points are: in the Lagrangian framework, by constructing seepage field, and comprehensively calculating the stokes drag, dielectrophoresis force and Brownian force suffered by microplastic particles to track its movement, while explicitly introducing the adsorption and desorption between particles and pore wall, to simulate the migration trajectory and occurrence state of microplastic in heterogeneous porous medium.The application provides a high-precision simulation tool for revealing the environmental fate and health risk of microplastics in groundwater systems.

The invention discloses a method for quickly removing bubbles in a porous medium based on electric field regulation and control, which comprises the following steps: arranging an electrode in a mold, and applying a non-uniform electric field to a porous medium flow field containing bubbles through the electrode in a resin impregnation process; based on a non-uniform electric field, dielectrophoretic force is induced to be generated at an interface of fluid-bubble-porous medium; through dielectrophoretic force, the bubble form is regulated and controlled, and the bubbles are driven to accelerate directional migration, so that the bubbles escape from the porous medium. According to the method, the limitation that a traditional bubble removal method mainly depends on pressure gradient and capillary force passive gaming is overcome, efficient, accurate and active regulation and control and rapid removal of the tiny bubbles in the porous medium are achieved, and the porosity of the composite material is effectively reduced.

The invention provides an electric separation device and method for removing solid catalyst particles in catalytic slurry oil, and belongs to the technical field of slurry oil solid removal and petrochemical engineering, the device comprises an outer cylinder, an inner cylinder and a central metal rod which are coaxially arranged, the inner cylinder is connected with a high-voltage power supply to form a non-uniform electric field, and the outer cylinder and / or the inner cylinder are / is of a variable-diameter structure; due to the design, the electric field gradient is enhanced in a variable-diameter area, so that the dielectrophoretic force acting on the superfine catalyst particles is increased; meanwhile, according to the fluid continuity principle, the flow speed of the oil slurry decreases progressively due to increase of the cross section area of a channel in the flowing process from top to bottom, the particle retention time is prolonged, and fluid drag force is reduced. Through the synergistic effect of the two effects, the removal efficiency of superfine particles with the diameter smaller than 1 micron is remarkably improved. The device is simple in structure, does not need a complex control system, can achieve efficient and stable solid removal under moderate electric field intensity, and is suitable for various complex working conditions.

The application provides a cell inertia sorting device and method based on dielectric enhancement, and belongs to the technical field of cell filtering and sorting. The device comprises a spiral structure inertia sorting module and a dielectrophoresis enhancement sorting module. Specifically, the device comprises a PDMS cover sheet layer, an Ag-PDMS three-dimensional electrode layer, an ITO wire layer and a glass substrate layer. The spiral structure inertia sorting module can focus cells of different sizes at different balance positions. In the dielectrophoresis enhancement sorting module, a long strip-shaped three-dimensional electrode group and a semicircular three-dimensional electrode are designed to provide strong and stable dielectrophoresis force for cells. Since different cells are subjected to dielectrophoresis forces of different sizes and directions, different directional deviations are generated, so that the separation distance of the two kinds of cells is increased, and the inertia sorting effect is enhanced. The inertia technology and the dielectrophoresis technology are organically combined, the sorting precision is improved, and high-precision and high-throughput separation between different cells is realized.

The invention relates to determining the frequency of TTfield therapy based on electrical characteristics of targeted cancer cells. Cancer treatment using TTField (Tumor Treatment Field) may be tailored for each individual subject, by obtaining cancer cells from the subject, determining electrical characteristics of the cancer cells (e.g., dielectrophoretic force, cell membrane capacitance, etc.), determining a frequency for TTField based on the determined electrical characteristics, and treating cancer by applying TTField to the subject at the determined frequency. Further, cancer treatment may be planned for each individual subject, by obtaining cancer cells from the subject, determining electrical characteristics of the cancer cells, predicting whether TTField will be effective to treat cancer based on the determined electrical characteristics, and treating the subject by applying TTField if the prediction indicates that TTField is effective.

The invention discloses a battery charging and discharging method and device and a medium, relates to the field of batteries, and automatically triggers capacity recovery of the battery when the battery reaches a preset recovery condition. And pulse parameters are determined in real time according to the current capacity fading rate of the battery, so that the configuration and application of the repair pulse are carried out. A restoration pulse is applied to an electrode of the battery, so that a neutral particle of an isolated silicon-lithium compound in the battery can generate a dielectrophoresis effect under the action of an electric field generated by the restoration pulse, and the isolated silicon-lithium compound is controlled to move towards the electrode based on the action of dielectrophoresis force, so that the isolated silicon-lithium compound is in contact with a binder in the electrode; and the conductive network can be adhered to the conductive network of the electrode again under the action of the adhesive, and is reconnected with the conductive network to participate in subsequent electrochemical reaction, so that the capacity recovery of the electrode is realized. The pulse parameters are determined according to the real-time capacity attenuation rate of the battery, and can adapt to the real-time characteristics of the battery to realize capacity recovery, so that the cycle life of the battery is effectively prolonged.

Methods of selectively positioning a micro-object in a microfluidic device are described in this application. The microfluidic device can comprise an enclosure having an inlet, an outlet, and a flow region connecting the inlet and outlet, and an electrode activation substrate having a photoconductive layer. The methods of selectively positioning can comprising: projecting a first light beam on an electrode activation substrate of the microfluidic device, wherein the first position is proximal to the first micro-object, and wherein the first light beam activates a positive dielectrophoresis (DEP) force within the enclosure sufficient to capture the first micro-object; and projecting a second light beam upon a second position on the electrode activation substrate, wherein the second position is adjacent to or at least partially surrounding the first position, without overlapping the first position, the second light beam activating a positive DEP force within the enclosure sufficient to capture second micro-objects other than the first micro-object. The methods of selectively positioning can further comprise moving the first light beam towards a third position on the electrode activation substrate, wherein the DEP force activated by the first light beam is sufficient to move the first micro-object to the third position. Optionally, the methods can include moving the second light beam in relation to the first light beam to prevent micro-objects other than the first micro-object from being captured by the first light beam. Other embodiments are described.

The invention relates to the technical field of electronic measuring instrument manufacturing, and discloses a surface enhanced Raman detection system and method based on electric field regulation and control plasmon coupling. The system comprises a micro-fluidic chip assembly with a micron-order interdigital electrode, an electric field modulation driving unit, a photoelectric signal acquisition unit and a phase lock analysis and arbitration processing unit, and the electric field modulation driving unit applies periodic alternating current driving voltage to the interdigital electrode; the SERS active nanoparticles are driven by dielectrophoretic force to generate periodic aggregation and diffusion motion which is twice of the basic frequency, the phase-locked analysis and arbitration processing unit extracts the frequency doubling amplitude in the spectral signal as a concentration characterization value, and outputs a result only when a phase lag component is located in a preset effective interval. SERS signals are stripped from direct-current noise, and the measured signal-to-noise ratio and reliability are improved.

The utility model provides a kind of cell well plate, from bottom to top sequentially include substrate, middle layer, hydrophobic layer, the middle layer is equipped with a plurality of sample wells, the sample well is communicated with the substrate, electrode is provided on the substrate, and the electrode is located the sample well below;The electrode is used to generate uneven electric field, so that cell or bacteria is inclined to the side movement of uneven electric field and is settled in the bottom of the sample well;The middle layer is used to clean sample liquid;The hydrophobic layer is used to keep sample in the sample well and sample well between not connected and flows in series.The utility model adds electric field below well plate, improves cell settling velocity by dielectrophoresis force effect, and cell (or bacteria) is not easy to lose under the action of dielectrophoresis force after settling, and has better retention rate in laminar flow cleaning process.

The invention discloses a multi-physics field coupling simulation method for micro-scale micro-plastic migration occurrence, and belongs to the field of ecological environment. The method aims at solving the problems that an existing micro-plastic migration model ignores the interface adsorption process, is difficult to couple with the multi-physical field effect and is insufficient in heterogeneous environment adaptability. The method is characterized in that under a Lagrange framework, a seepage field is constructed, stokes drag force, dielectrophoretic force and Brownian force borne by micro-plastic particles are comprehensively calculated to track movement of the micro-plastic particles, and meanwhile, adsorption and desorption effects between the particles and pore wall surfaces are explicitly introduced; therefore, the migration track and the occurrence state of the micro-plastic in the heterogeneous porous medium are simulated. The invention provides a high-precision simulation tool for revealing environment fate and health risk of microplastics in an underground water system.

The invention provides a liquid marble control device based on dielectric driving, and relates to the technical field of liquid marble control, the liquid marble control device comprises a power supply, a displacement mechanism and an electrode, the electrode is connected with the power supply through a wire, the power supply is used for controlling the electrode to be electrified, and the displacement mechanism is used for controlling the electrode to move along a preset route above a pool. The electrodes are used for generating an electric field after being electrified. The electrodes are arranged above the liquid marbles in a spaced mode, strong-point charges are formed at the tips of the electrodes, and a non-uniform electric field is generated in the surrounding space. Under the action of a non-uniform strong electric field, positive and negative charges in the liquid marble generate micro-scale relative displacement, so that the whole marble is polarized. The polarization effect generates net dielectrophoretic force in a non-uniform electric field, the direction of the net dielectrophoretic force points to an area with high electric field intensity, and driving of the liquid marbles is achieved. According to the liquid marble conveying device, track diversity is provided for liquid marble conveying, the liquid marble conveying device is more suitable for long-distance conveying, and meanwhile the problem of pollution or damage caused by direct contact with an electrode is avoided.

The present disclosure provides a display device using semiconductor light-emitting elements mounted on an assembly substrate in fluid, and a method for manufacturing same. The assembly substrate on which semiconductor light-emitting elements are mounted (assembled) comprises first assembly electrodes and second assembly electrodes intersecting the first assembly electrodes. By a dielectrophoretic force generated by applying a voltage to the assembly electrodes, semiconductor light-emitting elements may be mounted at the intersections of the assembly electrodes. In addition, by using the assembly substrate as a repair substrate, a region of the substrate in which assembly defects have occurred can be repaired, after assembly or transfer of the semiconductor light-emitting elements.

The application discloses a method for programmable fast assembly of SERS substrates driven by photo-induced dielectrophoresis, and relates to the technical fields of micro-nano manufacturing and surface enhanced Raman spectrum detection, and the method comprises the following steps: constructing a photo-induced electrophoresis chip; obtaining micro-nano particles and target objects to be detected; mixing the micro-nano particles and the target objects to be detected to obtain a suspension, and injecting the suspension into a liquid cavity of the photo-induced electrophoresis chip to obtain an assembled photo-induced electrophoresis chip; based on the assembled photo-induced electrophoresis chip, driving the micro-nano particles in the suspension to capture the target objects to be detected according to photo-induced convection and dielectrophoresis force through a programmable spatial light modulation device, obtaining a chimeric substrate, and performing in-situ surface enhanced Raman spectrum detection and quantitative analysis. The application solves the problems of low efficiency, poor structure controllability, insufficient uniformity and liquid phase incompatibility of traditional micro-nano assembly technology, and realizes efficient aggregation, reconfigurable assembly and in-situ SERS detection of the micro-nano particles and the target objects to be detected in a liquid environment.

The invention discloses a method for driving a programmable rapidly-assembled SERS (Surface Enhanced Raman Scattering) substrate through photoinduced dielectrophoresis, and relates to the technical field of micro-nano manufacturing and surface-enhanced Raman spectroscopy detection.The method comprises the steps that a photoinduced electrophoresis chip is constructed; obtaining micro-nano particles and a to-be-detected target object; mixing the micro-nano particles with a to-be-detected target object to obtain a suspension, and injecting the suspension into a liquid cavity of the light-induced electrophoresis chip to obtain a to-be-assembled light-induced electrophoresis chip; based on a to-be-assembled photo-induced electrophoresis chip, a programmable spatial light modulation device drives micro-nano particles in the suspension according to photo-induced convection and dielectrophoretic force to capture a to-be-detected target object, a chimeric substrate is obtained, and in-situ surface enhanced Raman spectroscopy detection and quantitative analysis are performed. The problems that a traditional micro-nano assembly technology is low in efficiency, poor in structural controllability, insufficient in uniformity and incompatible in liquid phase are solved, and efficient aggregation, reconfigurable assembly and in-situ SERS detection of the micro-nano particles and the target object to be detected in the liquid environment are achieved.

The invention relates to the field of power system high-voltage insulation and intelligent sensing monitoring, in particular to an insulating oil multi-parameter rapid synchronous detection device and method, and the device comprises a fluid driving unit, an acoustoelectric layering test pipeline, a breakdown test unit and a self-healing damping valve. According to the system, through the synergistic effect of an ultrasonic standing wave field and dielectrophoretic force, a virtual layered structure of central rich gas core flow-peripheral pure circulation flow is constructed in a pipeline; the core of the device is that a hollow breathable fiber membrane tube is used for degassing analysis, and meanwhile, a peripheral shielding electrode is used for measuring the dielectric loss of oil without bubble interference; according to the invention, the hydrodynamic contradiction between a strong disturbance fluid environment required by oil-gas separation and an undisturbed steady-state laminar flow environment required by dielectric loss measurement is solved, and rapid and synchronous detection of multiple parameters of the insulating oil is realized.

The application discloses a micro-fluidic chip for processing exosomes and a manufacturing method thereof, and relates to the technical field of biological detection. Based on the structure of the micro-fluidic chip, when the nano-hole electrode layer and the nano-grating sensing electrode layer of the optical biosensing array unit are connected to a power supply, due to the different diameters of the detection channels, the two asymmetric gold nano-electrodes of each detection channel form a non-uniform electric field, the nanoparticles of the exosomes are polarized, dielectrophoresis force is generated on the nanoparticles, and the nanoparticles are driven to move and gather on the surface of the nano-grating sensing electrode layer at the bottom, so that the nanoparticles are effectively detected by the nano-grating sensing electrode layer, and the effect of efficiently and highly sensitively detecting the exosomes is achieved.

The application particularly relates to a dielectrophoresis precision grading method and device for boron-containing diamond micro-powder. The method comprises the following steps: dispersing the boron-containing diamond micro-powder in a dispersion medium with an electrical conductivity less than 10 ‑3 S / m; passing the dispersed suspension into a dielectrophoresis grading device; applying electrophoretic interference of a shielding surface charge with a frequency of 5-20 MHz in the device, and realizing precision grading according to particle size by dielectrophoretic force. The application adopts a two-stage coupling grading strategy: the first stage of a parallel plate electrode unit realizes pre-selection according to boron content by using Maxwell-Wagner relaxation frequency difference, and the second stage of an inclined electrode array unit realizes precision grading according to particle size, and more than 5 narrow distribution particle grades can be obtained by single operation, the particle size span value of each particle grade is less than or equal to 0.5, and the particle size-boron content two-dimensional grading is realized, the particle size of each collection area after grading is relatively concentrated, the overlapping degree between adjacent particle grades is low, and the needs of precision applications such as super-precision grinding, heat-conducting filler and the like are met.

Provided are a tweezer manipulation system based on a transduction device, a preparation method, and a manipulation method, relating to the field of physical field manipulation. The tweezer manipulation system comprises a transduction device and an external field control device. The transduction device generates a spatially gradient electric field under remote excitation by ultrasonic, magnetic, and optical fields generated by the external field control device, thereby achieving non-contact and non-destructive manipulation of objects in solid, liquid and gaseous phases on the basis of the dielectrophoretic force exerted on the objects under the gradient electric field. The tweezer manipulation system allows for coordinated regulation of the magnitude and direction of the dielectrophoretic force by means of the transduction device and the external field control device, enables manipulation of objects across size scales ranging from nanometers to centimeters, achieves precise manipulation of both single and multiple objects, and has huge application potential in the fields of chemical reactions, biochemical sensing, cell manipulation, and micro / nanorobots, etc.

This invention discloses a microfluidic chip based on a gradient electric field and its application in the enrichment of micro- and nano-plastics, belonging to the field of environmental pollutant detection and treatment. The chip includes a sample channel and an enrichment channel arranged vertically and parallel to each other. Multiple electrodes are uniformly distributed along the length of the channel on the upper surface of the sample channel and the lower surface of the enrichment channel, with a one-to-one correspondence between the electrodes on the sample channel and the electrodes on the enrichment channel. The electrodes can be independently voltaged, forming a positive gradient electric field that increases along the sample flow direction, causing negatively charged micro- and nano-plastics in the sample channel to migrate to the enrichment channel under the action of dielectric force. This chip is suitable for automated, high-throughput enrichment of low-concentration micro- and nano-plastics in aquatic environments, exhibiting good versatility and scalability, providing an effective tool for the monitoring and control of microplastics.

The droplet separation device and method based on a digital microfluidic chip provided in this application include a square electrode array disposed on the digital microfluidic chip and an interdigital electrode assembly disposed on the square electrode array. When a droplet containing a droplet moves to the interdigital electrode on which a high-frequency dielectrophoresis signal is applied, the droplet is subjected to the resultant force of the dielectrophoresis force and the fluid drag force, causing the droplet to align in a certain direction to achieve the tearing of the droplet, resulting in sub-droplets with a more uniform droplet distribution. This solves the problem of more controllable and uniform droplet sorting and separation on a digital microfluidic platform, and can make the existing droplet separation based on digital microfluidic chips more reliable.

The invention relates to a method for operating a fluidic microsystem (100) for the dielectrophoretic manipulation of suspended particles (1) having a particle diameter in a suspension liquid (2), wherein the microsystem (100) comprises: —a channel (10) having a longitudinal direction; —an electrode device (20) having an electrode (21), the longitudinal extent of which deviates from the longitudinal direction of the channel (10) and which has individually controllable electrode segments (22) for producing dielectrophoretic forces which act on the particles (1), each electrode segment (22) having a deflection angle α, relative to the longitudinal direction of the channel (10), and a segment length (si), which determine a segment offset (Di) perpendicular to the longitudinal direction of the channel (10); and —a control device (30). The method comprises: —producing a flow of the suspension liquid (2) with a flow velocity so that the particles (1) successively pass through an interaction region of the electrode (21), which interaction region is spanned by the electrode segments (22); and —activating the electrode segments (22) in order to deflect the particles (1) onto predetermined motion paths (4, 5), which are determined by a superposition of flow forces in the flow of the suspension liquid (2) and of the dielectrophoretic forces at the electrode segments (22). During the passage of each particle, each of the electrode segments (22) which are passed by the particle (1) is activated in a clocked manner for a predetermined activation duration, according to the desired motion path (4, 5), the activation duration of each electrode segment (22) being determined by the quotient of the segment length (si) of the electrode segment (22) and the flow velocity. The electrode segments (22) are dimensioned such that the segment offset (Di) of each electrode segment (22) is less than the particle diameter. For the deflection of each particle (1), at least two successive electrode segments (22) cooperate.

The invention discloses a microfluidic biosensor for detecting Candidatus Liberibacter asiaticum and a detection method thereof, and belongs to the technical field of biosensing. The sensor integrates a micro-fluidic chip of a separation area, a concentration area and an electrochemical detection area. The separation area is a spiral micro-channel; the concentration area is provided with an interdigital working electrode array, and target bacteria are captured and enriched through dielectrophoretic force; the electrochemical detection area is provided with a sensing working electrode, and the surface of the working electrode is sequentially modified with an MXene-coated AgNPs nano composite material layer, a nucleic acid aptamer layer specifically combined with outer membrane protein OmpA of the Candidatus Liberibacter asiaticum and a sealant layer. During detection, after a sample is separated and enriched, target bacteria are combined with the aptamer to cause electrochemical impedance change, and a result is output after treatment. According to the invention, sample pretreatment, target enrichment and high-sensitivity detection are integrated, rapid, simple and high-specificity on-site detection of the Candidatus Liberibacter asiaticum is realized, and the method is suitable for large-scale field screening.

The invention discloses a single cell density prediction method based on machine learning, and relates to the technical field of machine learning and cell quantitative analysis, the implementation of the method comprises the following steps: controlling cells to move in a microfluidic environment through dielectrophoretic force generated by a light-induced dielectric technology; collecting motion state change data of the to-be-detected cells in the sedimentation process; performing data cleaning and normalization on the data; time points in the cell sedimentation process and image frame numbers matched with the corresponding time points are extracted, and a feature vector is formed by the time points and the image frame numbers to serve as a feature data set; constructing a cell density prediction model by using a machine learning algorithm, and performing training and testing; and evaluating a prediction result by using indexes such as R2, RMSE, MSE, MAE and the like, and selecting an optimal model. According to the prediction method based on machine learning, the problems that a traditional method needs complex image processing to calculate the cell radius, calculation is complex and time cost is high are solved, and the effects of high efficiency and high accuracy are achieved; the method has the application prospects of improving the research efficiency of cell-related physical parameters and providing reference for prediction of other biological parameters.