34 results about "Viscoelastic fluid" patented technology

Described here are systems and methods for accessing Schlemm's canal and for delivering an ocular device, tool, or fluid composition therein. The ocular devices may maintain the patency of Schlemm's canal without substantially interfering with transmural fluid flow across the canal. The fluid composition may be a viscoelastic fluid that is delivered into the canal to facilitate drainage of aqueous humor by disrupting the canal and surrounding trabeculocanalicular tissues. Some systems described here may be configured to cut or tear the trabecular meshwork with the body of an elongate member located within Schlemm's canal. Other tools for disrupting these tissues and minimally invasive methods for treating medical conditions associated with elevated intraocular pressure, including glaucoma, are also described.

The application discloses an aortic valve guide wire and a use method thereof, which comprises a head section, a transition section and a support section connected in sequence along an axial direction; the head section is composed of a polymer and further comprises a deformation capsule, at least one closed unit embedded in the head section, and an internal sealing electric field sensitive viscoelastic fluid; a mesh cable is arranged on the surface of the deformation capsule and extends to the transition section; the transition section and the support section are provided with a conductive film on the surface, and the conductive film is connected with the mesh cable and used for applying a non-uniform electric field to the deformation capsule to generate a regional viscosity difference and drive the head section to bend in a direction.The electric field sensitive viscoelastic fluid built in the head section generates a regional viscosity difference under the action of the non-uniform electric field, and the difference is converted into a directional bending moment through the synergistic effect of the mesh cable and the conductive film, so that the head of the guide wire can quickly respond to an external electric signal and accurately deflect.

Described here are systems and methods for accessing Schlemm's canal and for delivering an ocular device or fluid composition therein. The ocular devices may maintain the patency of Schlemm's canal without substantially interfering with transmural fluid flow across the canal. The fluid composition may be a viscoelastic fluid that is delivered into the canal to facilitate drainage of aqueous humor by disrupting the canal and surrounding trabeculocanalicular tissues. Tools for disrupting these tissues and minimally invasive methods for treating medical conditions associated with elevated intraocular pressure, including glaucoma, are also described.

The invention discloses a viscoelastic fluid heat flow coupling topological optimization method for micro-channel system design. The method comprises the following steps: firstly, carrying out pretreatment, defining a viscoelastic fluid constitutive model, defining material attributes and carrying out finite element analysis; then constructing boundary conditions of the heat flow coupling topological optimization model; constructing a viscoelastic fluid heat flow coupling topological optimization mathematical description model, then constructing an optimization model, and finally verifying the topological optimization design result of the viscoelastic fluid system. According to the method, the heat flow coupling calculation of the viscoelastic fluid is carried out through the logarithmic tensor reconstruction method, and a relatively accurate analysis result can be obtained under a high Vesceng number; and in combination with a variable density topological optimization method with high design degree of freedom, a new configuration of a micro-channel system structure is obtained, and a new solution idea is provided for heat dissipation of a micro electronic component with high heat flux.

A method for measuring the material properties of a viscoelastic fluid using one or more vibrating transducers, the method comprising: vibrating one or more vibrating transducers within the viscoelastic fluid so as to generate a first wave propagating from a first surface of the one or more vibrating transducers and a second wave propagating from a second surface of the one or more vibrating transducers; during vibration of the one or more vibrating transducers, the first surface and the second surface being spaced apart from and oriented with respect to each other such that the first wave and the second wave combine with each other to produce a final constructive or destructive interference; and determining the material properties of the viscoelastic fluid based on the vibration of the one or more vibrating transducers within the viscoelastic fluid.

This invention relates to the field of oilfield chemistry, and particularly to a diverting agent based on thermally reversible dynamic covalent bonds, its preparation method, and its application. The diverting agent is a polymer cross-linked via dynamic covalent bonds, which are constructed by thermally controlled Diels-Alder and reverse Diels-Alder reactions. The polymer is copolymerized from hydrophilic monomers containing double bonds and a dynamic covalent cross-linking agent containing double bonds. The dynamic covalent cross-linking agent containing double bonds is a polymerizable compound containing furan or cyclopentadienyl groups. During the plugging stage, under high-temperature conditions in deep or ultra-deep oil and gas reservoirs, the material transforms from rigid particles into a viscoelastic fluid, forming a temporary plugging layer at the pore or fracture entrance of high-permeability layers. During the degradation stage, pumping in a depolymerizing fluid triggers a reverse Diels-Alder reaction, achieving complete degradation. This solves the problem of poor temperature resistance and low strength of diverting agents, which cannot meet the needs of balanced oil and gas field development in deep or ultra-deep oil and gas reservoirs.

The application discloses a graphene preparation method based on interlayer stress resonance. Macroscopic mechanical rotation energy is converted into high-frequency and directional stress energy which can precisely act on the van der Waals force between graphite layers through a series of carefully designed physical processes. Under specific rotation conditions, unstable vortex structures (such as Taylor vortex flow) are generated in the confined fluid. When the stress wave formed by the vortex in the viscoelastic fluid is coupled with the intrinsic vibration frequency between the graphite layers, resonance phenomenon is triggered. The resonance can amplify the strain energy between the graphite layers, so that the interlayer van der Waals force is efficiently and selectively overcome under the condition of energy input far lower than the in-plane fracture threshold of carbon-carbon bond, and the graphene is exfoliated to obtain large and few-layer graphene.

The invention provides functional oil displacement fracturing fluid based on physical crosslinking as well as a preparation method and application of the functional oil displacement fracturing fluid. The preparation method of the fracturing fluid comprises the following steps: adding acrylic acid, acrylamide, 2-acrylamido-2-methylpropanesulfonic acid and N, N-dimethylacrylamide into water, adjusting the pH value of a system to 5-8, adding a dispersing agent, and then adding N-dodecyl acrylamide to obtain a water phase; adding an emulsifier into the white oil to obtain an oil phase; adding the water phase into the oil phase, and emulsifying to obtain an emulsion; adding an initiator into the obtained emulsion, and reacting; after the reaction is completed, adding a phase inversion agent to obtain an emulsion type resistance reducing agent; and adding the PCL-PEG-PCL into water, then adding the emulsion type resistance reducing agent, and stirring until the solution becomes a viscoelastic fluid, thereby obtaining the product. The fracturing fluid provided by the invention has the advantages of high sand-carrying property, low damage and high oil displacement property, and can solve the problems of poor sand-carrying property, flowback fluid pollution, difficult gel breaking, reservoir pollution and the like of the traditional fracturing fluid.

The invention discloses an electric field-viscoelastic micro-fluidic focused nanoparticle system with temperature controlled by dry ice. The electric field-viscoelastic micro-fluidic focused nanoparticle system comprises a micro-fluidic chip, a PMMA (polymethyl methacrylate) transparent heat insulation layer, the dry ice, a viscoelastic micro-fluidic chip matched with the dry ice, an electric field and a visual experiment system. According to the method, temperature control, viscoelastic fluid and an external direct-current electric field are combined to control small-size nanoparticles, and the temperature field of the micro-fluidic chip is regulated and controlled through dry ice and PMMA thickness, so that the temperature rise of the channel and the chip caused by the Joule heating effect of the external direct-current electric field in the channel fluid is eliminated; further, stable and continuous focusing of the nanoparticles by a high-voltage electric field-viscoelastic microfluidic method is promoted. Meanwhile, the temperature field is regulated and controlled by the dry ice, so that the temperature-sensitive particles can be protected from being damaged by high temperature during operation. The high-voltage electric field-viscoelastic microfluidics using the dry ice to control the temperature can effectively focus the nano-particles at high flux under high electric field intensity, so that accurate control, focusing and enrichment of the small-size nano-particles are realized.

The invention discloses a graphene preparation method based on interlayer stress resonance. Macroscopic mechanical rotation energy is converted into high-frequency and directional stress energy capable of accurately acting on Van der Waals force between graphite layers through a series of well-designed physical processes. Under a specific rotation condition, an unstable vortex structure (such as Taylor vortex) can be generated in a limited fluid, and when a stress wave formed by the vortex in a viscoelastic fluid is coupled with an intrinsic vibration frequency between graphite layers, a resonance phenomenon can be caused. The resonance can amplify the strain energy between the graphite layers, so that the Van der Waals' force between the layers is efficiently and selectively overcome under the energy input condition far lower than the in-plane fracture threshold of the carbon-carbon bond, the graphene is delaminated, and the large-piece and few-layer graphene is obtained.

The application relates to the field of exploration geophysical seismic fluid identification, in particular to a frequency-variable solid-liquid decoupling viscoelastic fluid factor prestack seismic inversion method. The method comprises the following steps: step 1, carrying out equal-interval frequency division processing on seismic data; step 2, carrying out frequency division elastic impedance inversion by using the frequency division seismic data in step 1; step 3, frequency-variable solid-liquid decoupling fluid factor inversion equation construction; step 4, carrying out frequency-variable solid-liquid decoupling fluid factor inversion equation coefficient inversion for each prestack angle stack and sampling point; and step 5, frequency-variable solid-liquid decoupling fluid factor inversion. The method improves the fluid factor inversion precision on the basis of conventional solid-liquid decoupling fluid factor inversion by establishing a reference frequency and frequency division frequency calculation process.

The invention belongs to the technical field of fluid mixing, and discloses a multi-stage leaf-shaped static mixer for mixing viscoelastic fluid and Newtonian fluid, and multi-stage mixing units which are sequentially connected end to end in the longitudinal direction are arranged between a fluid input channel and a fluid output channel; the fluid input channel is used for connecting the Newtonian fluid inlet and the viscoelastic fluid inlet, and the fluid output channel is used for leading out mixed liquid; the mixing unit is a flat shell composed of an upper surface, a lower surface, a first outer contour surface, a first inner contour surface, a second outer contour surface and a second inner contour surface, and an upstream confluence area, a shunting area and a downstream confluence area are sequentially formed between the first outer contour surface and the first inner contour surface and between the second outer contour surface and the second inner contour surface. According to the invention, the viscoelastic fluid can be rapidly mixed under the condition of low shear disturbance, so that the fluid forms secondary vortex and spiral flow along the main flow direction in the mixing area, and the mixing rate of the viscoelastic fluid and the Newtonian fluid is obviously improved.

The application is a method and system for constructing a wide-temperature-range constitutive model of a viscoelastic fluid in a space environment, which relates to the cross-technical field of computational materials science, aerospace tribology and fluid dynamics, and comprises the following steps: performing sinusoidal shearing on a balanced full-atom model at multiple key temperature points, simulating the dynamic response under sinusoidal shearing to obtain original strain time series data and original stress time series data, performing filtering and smoothing processing and feature extraction to obtain waveform features, and calculating shear rate time series data; inputting the filtered and smoothed original strain time series data and the shear rate time series data into a constitutive mathematical model to obtain predicted stress, minimizing the error between the predicted stress and the filtered and smoothed original stress time series data for multi-stage optimization, and obtaining a wide-temperature-range constitutive model of a viscoelastic fluid. The application solves the technical problem that the constitutive model is difficult to obtain rheological parameters of a space lubricating fluid under wide-temperature-range and large-amplitude shearing, resulting in low prediction accuracy.

The invention provides a medical waterproof adhesive as well as a preparation method and application thereof. The preparation method of the medical waterproof adhesive comprises the following steps: firstly preparing solid gel, and then adjusting the rheological property of the solid gel to obtain the viscoelastic fluid waterproof adhesive. The preparation method of the adhesive provided by the invention is simple and convenient to operate, controllable in process, high in repeatability and low in cost. The prepared waterproof adhesive is stable in performance, shows good injectability and spreadability at normal temperature, and is convenient for surgical operation; in a wet ocular surface environment, a pre-formed network can effectively resist immediate flushing and dilution of body fluids such as tears, aqueous humor and blood, so that stable residence and accurate positioning on the surface of a target tissue are ensured; under the irradiation of a light source with specific wavelength, the gel is subjected to polymerization reaction, a compact and firm secondary cross-linked network is quickly formed under a wet condition, and stable and reliable in-situ solidification and tissue adhesion are realized.

A toy kit includes a container, a toy configured to be disposed within the container and having a coating configured to be dissolved in a liquid, and a powder material. The powder material, the coating dissolved by the liquid, and the liquid are configured to mix to provide a viscoelastic fluid.

This invention discloses a microfluidic chip for pre-focused cell sorting. Newtonian and viscoelastic fluids are introduced into different inlets of the chip. Through the polygonal flow channel shape within the microfluidic chip, a stable viscoelastic-Newtonian interface is generated by the co-flow of the two solutions. The inertial and viscoelastic effects generated within the microfluidic channels induce inertial lift at the microchannel walls and viscoelastic lift in the viscoelastic solution, both acting on the cell particles within the channels. Furthermore, the driving forces for the passive separation of cell particles, such as inertial and viscoelastic lift, strongly depend on the particle diameter. Particles of different diameters are affected by different resultant forces. Therefore, cell particles of different diameters accumulate different distances during migration within the microchannels, pre-arranging the lateral migration patterns of the particles and ultimately achieving sorting at different channel outlets.

A viscoelastic fluid composition includes a viscoelastic surfactant composition ranging from about 0.1 wt. % to about 10 wt. % based on a total wt. % of the viscoelastic fluid composition. The viscoelastic fluid composition further includes crystalline sodium sulfate cellulose (NaSC) nanoparticles ranging from about 0.1 wt. % to about 10 wt. % based on the total wt. % of the viscoelastic fluid composition.

The invention discloses a temperature-sensitive magnetic bead, a preparation method thereof and related application of the temperature-sensitive magnetic bead in early cancer screening, and the temperature-sensitive magnetic bead is prepared by taking an unsaturated superparamagnetic bead with vinyl on the surface as a matrix through an in-situ free radical polymerization mode. N-isopropylacrylamide, acrylamide and oligomeric (ethylene glycol) methyl ether methacrylate are initiated to be copolymerized on the surfaces of the magnetic beads to form a temperature-sensitive polymer brush layer with an adjustable low critical solution temperature (LCST). The temperature-sensitive magnetic beads are in a hydrophobic collapsing state under the condition of 37-39 DEG C, are maintained in a viscoelastic fluid state beneficial to dynamic replacement of low-abundance proteins, and can efficiently adsorb the low-abundance proteins in plasma; the temperature-sensitive magnetic beads are rapidly converted into a hydrophilic stretching state at the temperature lower than 36 DEG C, and the multi-point interaction between the proteins and the temperature-sensitive magnetic beads is synchronously weakened by utilizing micromechanical ejection force generated by phase change, so that the proteins are completely eluted from the surfaces of the magnetic beads.

The invention provides a method for calculating a stabilized viscoelastic fluid-solid coupling problem based on an overlapped grid, and relates to the technical field of fluid-solid coupling calculation, the method comprises the following steps: processing a flow field region and solid particles to obtain an interpolation boundary, a contribution unit and an interpolation unit, and carrying out flow field calculation on a background grid to obtain background grid flow field information; transmitting the background grid flow field information to the sub-grids to obtain the flow field information of the sub-grids; calculating by using the flow field information of the sub-grids through a finite element method to obtain updated flow field information of the sub-grids; transmitting the updated sub-grid flow field information to a background grid by using bilinear Lagrange interpolation to obtain updated background grid flow field information; based on the updated background grid flow field information, parameter iteration updating is carried out through calculation, and simulation data of the motion trail and the rotation state of the solid particles in the flow field area are obtained. According to the method, the problems of low precision and low efficiency of fluid-structure interaction calculation are solved.

Described here are systems and methods for accessing Schlemm's canal and for delivering an ocular device or fluid composition therein. The ocular devices may maintain the patency of Schlemm's canal without substantially interfering with transmural fluid flow across the canal. The fluid composition may be a viscoelastic fluid that is delivered into the canal to facilitate drainage of aqueous humor by disrupting the canal and surrounding trabeculocanalicular tissues. Tools for disrupting these tissues and minimally invasive methods for treating medical conditions associated with elevated intraocular pressure, including glaucoma, are also described.

Described here are systems and methods for accessing Schlemm's canal and for delivering an ocular device or fluid composition therein. The ocular devices may maintain the patency of Schlemm's canal without substantially interfering with transmural fluid flow across the canal. The fluid composition may be a viscoelastic fluid that is delivered into the canal to facilitate drainage of aqueous humor by disrupting the canal and surrounding trabeculocanalicular tissues. Tools for disrupting these tissues and minimally invasive methods for treating medical conditions associated with elevated intraocular pressure, including glaucoma, are also described.

The invention relates to a high-performance magnetorheological viscoelastic fluid and a preparation method thereof. The method comprises the following steps: (1) dissolving polybutylene in heptane to form a solution A; (2) adding polyisobutene into the solution A to obtain a polyisobutylene / polybutylene mixed solution; (3) the carbonyl iron powder particles are subjected to acid etching treatment and cleaned to be neutral, and carbonyl iron powder particles A are obtained; (4) adding the carbonyl iron powder particles A into an ethanol mixed solution, and adjusting the pH value to obtain carbonyl iron powder particles B; (5) coating the carbonyl iron powder particles B with a silane coupling agent to obtain carbonyl iron powder particles C; and (6) dispersing the carbonyl iron powder particles C into a polyisoprene / polybutylene mixed solution, and heating to obtain the high-performance magnetorheological viscoelastic fluid. The prepared magnetorheological viscoelastic fluid is obviously superior to magnetorheological fluid in the aspects of dispersion stability and field shear yield stress, and can be applied to the damping application fields of hydraulic machinery, automobile suspension systems and the like.

Aspects include using a vibration transducer having a plurality of oscillators including a first oscillator (220) and a second oscillator (210), where the first oscillator and the second oscillator are coupled such that in a viscoelastic fluid (240), excitation (vibration) of the first oscillator excites the second oscillator (causing the second oscillator to vibrate). The frequency response of the double-oscillator combination is influenced by the fluid characteristics; thus measuring one or more of: i) resonant frequency, ii) vibration amplitude, iii) loss factor (or Q factor) of a vibration combination of the first oscillator and the second oscillator in the viscoelastic fluid may be used to determine one or more of: i) density, ii) viscosity (such as dynamic viscosity), iii) elasticity (such as storage modulus) of the viscoelastic fluid.

The application discloses a kind of viscoelastic liquid film flow control devices and its using method, belong to chemical liquid conveying machinery manufacturing technical field.The viscoelastic liquid film flow control device disclosed in the application, including base, sawtooth array and gradient wetting surface, under the control of gradient wetting provided by gradient wetting surface, viscoelastic liquid film flows evenly along wedge-shaped flow channel, when passing through sawtooth array, it is affected by "gradient wetting" and "tubeless side suction effect" of viscoelastic fluid, and carries out "intermittent" climbing flow.The viscoelastic liquid film flow control device disclosed in the application considers the influence of viscoelasticity on liquid film flow, and the sawtooth structure with "barb" characteristics can effectively slow down the elastic instability of liquid film flow, suitable for the flow control of viscoelastic liquid film, and has compact structure, reasonable design, and wide application prospect.

The application discloses a microfluidic chip design method and device based on a viscoelastic fluid binding effect, and the method comprises the following steps: selecting a microfluidic channel capable of effectively utilizing viscoelastic fluid instability to bind droplets; designing the size of the selected microfluidic channel; configuring a displacement fluid according to the size of the known microfluidic channel; constructing a viscoelastic fluid dynamics model according to the known microfluidic channel; determining critical conditions of droplet oscillation binding based on the viscoelastic fluid dynamics model and experimental results; and establishing a microfluidic design criterion based on viscoelastic fluid instability to bind droplets according to the critical conditions of droplet oscillation binding. The application can precisely and controllably realize oscillation binding of droplets based on the instability characteristics and unique microfluidic channel design of the viscoelastic fluid, so that the microfluidic chip with the oscillation binding function has a wider application scenario.

The utility model belongs to the technical field of metal sound barriers, and particularly relates to a novel inserting plate type metal sound barrier unit plate. The metal sound barrier unit plate comprises a cavity formed by a face plate, a back plate and edge beams, a sound absorber is installed in the cavity, the sound absorber is composed of a honeycomb structure block and a viscoelastic fluid filling layer arranged in the honeycomb structure block or the sound absorber is composed of a rock wool core layer and a sound transmission plate clamping the rock wool core layer, irregular cavity gaps are distributed in the sound transmission plate, and the irregular cavity gaps are distributed in the cavity. In the cavity, a front reverberation chamber is formed between the sound absorber and the panel, and a rear reverberation chamber is formed between the sound absorber and the back plate; the metal sound barrier unit plate is provided with a composite sound absorption system and has the advantages of being long-acting and stable in sound absorption and noise reduction, firm in structure, economical and durable.

The invention discloses an aortic valve guide wire and a using method thereof. The aortic valve guide wire comprises a head section, a transition section and a supporting section which are sequentially connected in the axial direction. The head section is made of a polymer, the deformation bag is embedded in at least one sealing unit in the head section, and electric field sensitive type viscoelastic fluid is sealed in the deformation bag; the net-shaped cable is arranged on the surface of the deformation bag and extends to the transition section; conductive films are arranged on the surfaces of the transition section and the supporting section, connected with the net-shaped cable and used for applying a non-uniform electric field to the deformation bag so as to generate regional viscosity difference and drive the head section to bend directionally. The electric field sensitive viscoelastic fluid arranged in the head section generates regional viscosity difference under the action of a non-uniform electric field, and the difference is converted into directional bending moment through the synergistic effect of the mesh cable and the conductive film, so that the guide wire head can quickly respond to an external electric signal and is accurately deflected.

A toy set includes a container, a toy configured to be disposed within the container and having a coating configured to dissolve within a liquid, and a powder material. The powder material, the coating dissolved by the liquid, and the liquid are configured to mix to provide a viscoelastic fluid.

A method of measuring a material property of a viscoelastic fluid using one or more vibratory transducers, the method comprising: vibrating one or more vibratory transducers in the viscoelastic fluid to generate a first wave propagating from a first surface of the one or more vibratory transducers and a second wave propagating from a second surface of the one or more vibratory transducers, wherein the first and second surfaces are spaced and oriented relative to each other such that, during vibration of the one or more vibratory transducers, the first and second waves combine with each other to provide a net constructive or destructive interference; and determining a material property of the viscoelastic fluid based on the vibrating of the one or more vibratory transducers in the viscoelastic fluid.

Microsurgical instruments having combined illumination, laser ablation, and viscoelastic injection functions. A surgical instrument includes a probe having a main lumen and a port at a distal end thereof. The probe may further include one or more optical fibers within the main lumen, the optical fibers configured to project laser light and illumination light. Laser light may be emitted from the distal end of the probe for disrupting an ocular tissue, while illumination light may be simultaneously emitted, axially or laterally, to provide enhanced visualization of the intraocular space during tissue disruptance. Upon disrupting the tissue, a viscoelastic fluid may be injected from the port to maintain an integrity of the intraocular space.