32 results about "Chaotic mixing" patented technology

Vertical electromagnetic stirring is used to produce low shear, stress, turbulent and chaotic mixing of a liquid material or suspension in a container regardless of the volume or container geometry. Movement of a magnetic stir bar is controlled by multiple magnetic fields. The magnetic fields are produced by a series of sequentially or non-sequentially activated inductor coils which produce asymmetrical stirring dynamics and random motions of the stir bar, causing the liquid material to be gently and effectively mixed throughout the container. Moving the stir bar in random and irregular patterns during the stirring operation creates turbulent and chaotic mixing dynamics. The stir bars used for supporting vertical magnetic stirring are specifically designed to optimize the effectivity of the mixing process by maximizing the length of the stir bar to quickly and gently mix the materials.

The invention discloses a method for preparing high polymer material scaffolds for the tissue engineering by collaboratively adopting mixing flow field and supercritical fluid. The method comprises the following steps: (1) two or more types of high polymer material are proportionally added into an extruder or an injection molding machine for melting; (2) the blend forms a continuous phase structure under the effect of mixing flow in a machine barrel (or under the combined action of the flow field and supercritical fluid which is injected); (3) the prepared blend with the continuous phase structure is foamed through supercritical fluid; and (4) the multi-component phase in foamed blend samples is removed, and less-component phase is remained as biological scaffolds. The method of the invention collaboratively adopts chaotic mixing and supercritical fluid to prepare the blend with the continuous phase structure in the condition that the less-component phase content is low, and enables the blend to be applied to the preparation of biological scaffolds for the tissue engineering. Moreover, the method has fewer processes, can realize batch production, and is easy to promote during the industrial production.

The invention discloses a magnetic stirring chaotic mixing method for the laminar flow in a microfluidic system and a device thereof. The rotary vortex generation, the vortex magnitude and rotation direction in a mixing chamber can be indirectly controlled by utilizing a sequential rotating magnetic field generated by a miniature polyphase magnetic field sequential generator to control the motion of a miniature magnetic stirrer bar in the mixing chamber on the outside of the mixing chamber of a microfluidic chip. The bottom of the miniature polyphase magnetic field sequential generator is provided with a sliding dolly freely sliding in a slide way, the position of the rotation magnetic field is displaced through the resultant force of the attractive force of an electromagnet to a permanent magnet and the elastic force of a miniature spring, the overall rotation position of the stirrer bar in the mixing chamber is displaced through controlling the overall displacement of the bottom electromagnetic field, and multistage chaotic convection is rapidly formed in the stirring (mixing) chamber by utilizing the rapid change of the rotation position of the stirrer bar and the fluid rotation inertia, so the full liquid mixing is guaranteed, and a problem that the microscale liquid is difficult to effectively mix because of the laminar flow is solved.

The invention discloses a homodromous self-cleaning double-screw extruder with a stretching function. The homodromous self-cleaning double-screw extruder with the stretching function comprises a machine barrel, a first screw and a second screw. The cross section of the first screw and the cross section of the second screw are both formed by multiple sections of circular arcs which are unequal in radius of curvature, and the cross section of the first screw and the cross section of the second screw are different in shape. The invention further provides a processing method of the homodromous self-cleaning double-screw extruder with the stretching function. According to the homodromous self-cleaning double-screw extruder with the stretching function and the processing method of the homodromous self-cleaning double-screw extruder with the stretching function, when the first screw and the second screw which are different in cross-section shape rotate in an identical direction, periodical change happens to a cross-section shape of a flow passage, so that a compression action and a squeezing action are applied on materials in the flow passage, a flowing space of the materials is compressed and expanded in a periodical mode, and therefore a chaotic mixing effect is generated, a mixing and heat transfer process is strengthened, a thermal and mechanical process which is plasticized is largely shortened, energy consumption is low, an energy-saving and consumption-reducing effect is notable.

The invention relates to a chaotic composite stirring system and a stirring method thereof, and belongs to the technical field of mechanical stirring equipment. The chaotic composite stirring system comprises a chaotic composite stirring device and a monitoring control system, wherein the chaotic composite stirring device comprises a stirring tank, a stirring component, a driving device, a transmission device, a top-blown rotational flow spray gun, a side-blown rotational flow spray gun, a bottom-blown rotational flow spray gun, an air inlet pipe I, an air inlet pipe II and an air inlet pipe III; the monitoring control system comprises a high-speed camera, a laser transmitter, a processor and an electrical conductivity meter. According to the chaotic composite stirring system disclosed bythe invention, combination of mechanical stirring and rotational flow gas stirring in variable-frequency flow is adopted, the area of a chaotic mixing zone can be strengthened by freely changing an eccentricity ratio of the stirring tank, the immersion depth of a stirring shaft and a deviation angle, the gas spray quantities of rotational flow spray guns can be subjected to variable-frequency regulation in real time and can be in periodic pulsation change, the chaotic composite stirring device is enabled to realize chaotic mixing within an extremely short time under low Reynolds number flow, and the mixing efficiency and the heat and mass transfer speed of fluid materials are improved to a large extent.

The invention discloses a novel elastic stirring paddle capable of improving fluid mixing effect. The novel elastic stirring paddle capable of improving fluid mixing effect comprises a stirring shaft,rigid stirring blades, rings, springs, and connecting devices; the novel elastic stirring paddle is at least composed of three layers including an upper layer, a middle layer, and a lower layer; therigid stirring blades of the upper layer and the rigid blades of the lower layer are fixedly arranged on the stirring shaft; the middle layer is capable of slide upward and downward; the rigid stirring blades of the three layers are connected with cylindrical spiral compression springs through the rings; the novel elastic stirring paddle is driven by a motor to rotate in a stirring tank, so that fluid is provided with mechanical energy, and the mixing process of materials in the stirring tank is reinforced. Under the interacting effect of the stirring shaft with the fluid, repeat contraction motion of the springs is realized, so that the middle layer rigid stirring blades are capable of rotating with the stirring shaft, and sliding upward and downward, the mixing isolation region of fluidis destroyed, fluid turbulence degree is increased, fluid chaotic mixing degree is increased; and in addition, the cutting effect on fluid is improved because of the structure characteristics of the cylindrical spiral compression springs, so that the structure interface of the fluid in the stirring tank can be destroyed more effectively.

The invention provides an injection molding machine and an injection screw thereof. The screw thread part of the injection screw comprises a feeding section, a compressing section and a homogenizing section; the homogenizing section is formed by large-pitch spiral grooves and spiral wave crests; and a gap between the spiral wave crests and the inner wall of a charging barrel is small, and when a motor drives the screw to rotate to plastify raw materials, all sol needs to cross the gap to obtain suitable cutting. The plastified sol enters the large-pitch spiral grooves and is conveyed into the material storage space of the charging barrel at relatively small damping and high efficiency. When the sol enters the deeper spiral grooves after crossing the spiral wave crests, eddy currents are formed to generate scroll currents along the depth of the spiral grooves; uniform chaotic mixing is conducted on the plastified sol, and heat exchange between the sol and the charging barrel is conducted more fully; and a uniform-temperature sol body with high quality is generated. According to the injection molding machine and the injection screw thereof, the material is fully plastified at smaller cutting displacement and higher plastifying efficiency. The defects of uncontrolled temperature rising, slipping of the screw, slow feeding and the like which are prone to occur in the sol melting process are overcome.

The invention belongs to the technical field of nanometer composite materials, and particularly relates to a nanometer stripping composite material and a preparation method and application thereof. The preparation method of the nanometer stripping composite material, provided by the invention, comprises the following steps: 1, mixing a polymer, layered nanosheets and a coupling agent to obtain a reaction mixture; 2, performing melt blending on the reaction mixture obtained in the step 1, and then extruding to obtain the nanometer stripping composite material, wherein extrusion is performed ina shear force field firstly, then in a tensile force field and finally in a chaotic mixing force field. The invention provides the nanometer stripping composite material and the preparation method andthe application thereof, and solves the technical problem that by the existing stripping method, the dispersing effect of the layered nanosheets in the polymer is poor.

The invention provides a method for preparing gold nanoclusters based on a microfluidic chip and belongs to the field of gold nanocluster synthesis methods. The method is characterized in that gold nanoclusters which have small monodisperse particle sizes and are protected by an alkyl carbon chain sulfhydryl monolayer are synthesized based on the microfluidic chip, hydrophobic modification is performed on the inner wall of the chip channel, and drops can be stably and smoothly formed and fused accurately and are uniform in size. Meanwhile, by the method, the drop sizes are small, chaotic mixing and mass transfer velocities are high, and reactants are uniformly distributed in the channel to facilitate nucleation and growth of nano-particles. The microfluidic chip is made of a transparent PDMS material, the material formation can be monitored and regulation and control can be performed on line in real time through integration with a microscope, the chip is simple in design, a plurality of groups of parallel reaction channels can be easily constructed, high-throughout synthesis can be performed, and the product yield is improved.

A self-cleaning extruding apparatus with two co-rotating screws and the method thereof are provided here. Said apparatus is comprised of a screw mechanism, a barrel (1), a feeding port (10), a venting port (11), and a discharge port (12). Said screw mechanism is comprised of the first screw with one tip (3) and the second screw with two tips (4). There is a baffle in the channel of the first screw and the baffle's height is lower than that of the screw flight. The baffle will cause hyperbolic perturbation in the shape of a ‘figure 8’ flow pattern above the top of the baffle. The first and second screws rotate at the same speed and touch each other at all times, thereby achieving a self-cleaning function.

The baffle will generate chaotic mixing in the screw channel caused by the hyperbolic perturbation. Topological chaos is also introduced into the screw channel by the mechanism ‘one part divided into two parts, then two parts converging into one part, and then one part divided into two parts once more’. Each of the screws in the present invention uses an asymmetrical flow channel geometrical shape, such that a periodic action like ‘compression—expansion—further compression—expansion further’ works. The above three enhancement mechanisms work together to efficiently accelerate melting and mixing.

The present invention provides a method for manufacturing a diffusely reflecting polarizer, comprising the steps of: coextruding first and second polymers through a chaotic mixer and a sheeting die to produce a cast sheet with a desired blend morphology and stretching said cast sheet to produce a composite film containing a first polymer having a birefringence of less than 0.02, with said first polymer being an amorphous material and a continuous phase, and a second polymer which forms a dispersed phase, and having an index of refraction that differs from said continuous phase by greater than about 0.05 along a first axis and by less than about 0.05 along a second axis orthogonal to said first axis, wherein said first and second polymers taken together along a first axis for one polarization state of electromagnetic radiation exhibit a diffuse reflectivity R_1d, a specular reflectivity R_1s, a total reflectivity R_1t, a diffuse transmittance T_1d, a specular transmittance T_1s, and a total transmittance T_1t, and along a second axis for another polarization state of electromagnetic radiation exhibit a diffuse reflectivity R_2d, a specular reflectivity R_2t, a total reflectivity R_2t, a diffuse transmittance T_2d, a specular transmittance T_2s, and a total transmittance T_2t, the said first and second axes being orthogonal, wherein the parameters of composition, chaotic mixing, stretch temperature and stretch ratio for the process and Tg, and refractive index of the first and second polymers are selected to satisfy the equations:

R_1d is greater than R_1g  (1)

and

T_2t/(1−0.5(R_1t+R_2t))>1.35.  (2)

The polylactic acid stereocomplex of the invention has a crystal melting peak temperature of 215°C or more, wherein the crystal melting peak is a single peak and has a peak half width of 12°C or less, and a crystal melting enthalpy of 60 J/g or more as measured by differential scanning calorimetry. The polylactic acid stereocomplex of the invention has a high melting point, good heat resistance, and a high level of mechanical properties and chemical resistance. The method of the invention for producing a polylactic acid stereocomplex includes chaotic mixing of 30 to 70 parts by weight of (A) poly-L-lactic acid and 30 to 70 parts by weight of (B) poly-D-lactic acid based on 100 parts by weight of the total of (A) poly-L-lactic acid and (B) poly-D-lactic acid. The polylactic acid stereocomplex producing method of the invention can produce a polylactic acid stereocomplex having, as measured by differential scanning calorimetry, a crystal melting peak temperature of 215°C or more, wherein the crystal melting peak is a single peak and has a peak half width of 12°C or less, and a crystal melting enthalpy of 60 J/g or more.

At least two or more components of thermoplastic resins are compounded by chaotic mixing to form a polymer alloy with a sophisticatedly controlled dispersed phase structure. In the polymer alloy, a dispersed phase having a non-periodic structure with a correlation length of 0.001 [mu]m to 0.5[mu]m and having a compactness (C) of 0.05 (C) 0.8, wherein the compactness (C) can form a molded product that also has transparency while maintaining the original good heat resistance or mechanical properties of the resins blended. A polymer alloy obtained by compounding at least two or more components of immiscible thermoplastic resins, containing a dispersion structure having particles with an average particle size of 0.001 to 1 [mu]m dispersed therein and satisfying 0 < (a)/(b) 1.5, wherein (a) and (b) represent a peak half width and the maximum wavenumber of the peak, respectively, in a spectrum obtained by plotting scattering intensity against wavenumber of scattered light in scattering measurement can form a molded product that also has transparency while maintaining the original good heat resistance and mechanical properties of the resins blended.

A single, or a cascade of magnetically actuated blades are used to simultaneously pump and mix fluids in continuous-flow microfluidic devices. The external magnetic field, which traps the blade and controls its motion, is generated by a carpet of micron-scale coils. The frequencies and amplitudes of the blade's translational and rotational motions are controlled by voltage and current waves that pass through the carpet of the microcoils. When the frequency ratios of the translational and rotational motions of the blades do not commensurate, the pumped fluid is mixed chaotically. Chaotic mixing is also achieved when a single blade moves on a rosette-like quasi-periodic path. The invented micro pumping and mixing device negates connections to external pumps, and does not need specially-carved channels to mix flowing liquid. The microcoils are printed or installed on glass or polymeric substrates. The blades can also be used as controllable gates in microfluidic circuits. The blades are embedded and sealed in microchannels or pumping chambers; the device composed of the blades and microcoils is disposable.

Provided is a resin composition having improved fluidity in a molten state maintained without lowering heat resistance, containing: a polymer being a reaction product of a first organic compound having a phenolic hydroxyl group and a second organic compound having a glycidyl group, Mw of the polymer being no greater than 10,000; and a thermoplastic resin other than the polymer. A proportion of the polymer contained in the resin composition is from 0.1% to 30% by mass. A melting point of the thermoplastic resin is no less than 200° C. The thermoplastic resin has a benzene ring in a molecule. The polymer and the thermoplastic resin have blended to form a homogeneous phase. Also provided are a molded product formed from the aforementioned resin composition, and a production method of a molded product including: kneading the resin composition by chaotic mixing; and molding a kneaded product obtained after the kneading.

The invention provides a microfluidic chip based method for synthesizing needle-like hydroxyapatite (HAp) nanoparticles. The method employs monodisperse microfluidic droplet as a micro reactor, and utilizes a microfluidic chip droplet fusion as a core technology to realize HAp nanoparticle synthesis on a chip. The method has the following advantages: the droplet has small volume, and chaotic mixing has a rapid mass transfer speed; droplet is used as the micro reactor, and a product is output by continuous phase to diminish adsorption on passageway wall and agglomeration of nanoparticles; a PDMS chip is transparent, and easy for online real-time monitoring of material formation and control; and the design of the chip is simple, and easy for construction of multiple parallel reaction channels for high-throughput synthesis, so as to improve the yield of product.