A device produces fine bubbles that has a simple configuration and that is capable of generating fine bubbles. This fine bubble generation device includes: a porous body having continuous pores; a liquid supply section that supplies a liquid to the porous body and causes the liquid to circulate through the continuous pores; and a liquid discharge section for discharging liquid that has circulated through the continuous pores.

The application relates to microfluidic apparatus and methods of use thereof. Provided in one example is a microfluidic device comprising: a first fluidic input and a second fluidic input; and a fluidic intersection channel to receive fluid from the first fluidic input and the second fluidic input, wherein the fluidic intersection channel opens into a first mixing chamber on an upper region of a first side of the first mixing chamber, wherein the first mixing chamber has a length, a width, and a depth, wherein the depth is greater than about 1.5 times a depth of the fluidic intersection channel; an outlet channel on an upper region of a second side of the first mixing chamber, wherein the outlet channel has a depth that is less than the depth of the first mixing chamber, and wherein an opening of the outlet channel is offset along a width of the second side of the first mixing chamber relative to the fluidic intersection.

The application relates to microfluidic apparatus and methods of use thereof. Provided in one example is a microfluidic device comprising: a first fluidic input and a second fluidic input; and a fluidic intersection channel to receive fluid from the first fluidic input and the second fluidic input, wherein the fluidic intersection channel opens into a first mixing chamber on an upper region of a first side of the first mixing chamber, wherein the first mixing chamber has a length, a width, and a depth, wherein the depth is greater than about 1.5 times a depth of the fluidic intersection channel; an outlet channel on an upper region of a second side of the first mixing chamber, wherein the outlet channel has a depth that is less than the depth of the first mixing chamber, and wherein an opening of the outlet channel is offset along a width of the second side of the first mixing chamber relative to the fluidic intersection.

This invention generally relates to systems and methods for the formation and/or control of fluidic species, and articles produced by such systems and methods. In some cases, the invention involves unique fluid channels, systems, controls, and/or restrictions, and combinations thereof. In certain embodiments, the invention allows fluidic streams (which can be continuous or discontinuous, i.e., droplets) to be formed and/or combined, at a variety of scales, including microfluidic scales. In one set of embodiments, a fluidic stream may be produced from a channel, where a cross-sectional dimension of the fluidic stream is smaller than that of the channel, for example, through the use of structural elements, other fluids, and/or applied external fields, etc. In some cases, a Taylor cone may be produced. In another set of embodiments, a fluidic stream may be manipulated in some fashion, for example, to create tubes (which may be hollow or solid), droplets, nested tubes or droplets, arrays of tubes or droplets, meshes of tubes, etc. In some cases, droplets produced using certain embodiments of the invention may be charged or substantially charged, which may allow their further manipulation, for instance, using applied external fields. Non-limiting examples of such manipulations include producing charged droplets, coalescing droplets (especially at the microscale), synchronizing droplet formation, aligning molecules within the droplet, etc. In some cases, the droplets and/or the fluidic streams may include colloids, cells, therapeutic agents, and the like.

The present invention generally relates to emulsions, and more particularly, to multiple emulsions. In one aspect, multiple emulsions are formed by urging a fluid into a channel, e.g., by causing the fluid to enter the channel as a “jet.” Side channels can be used to encapsulate the fluid with a surrounding fluid. In some cases, multiple fluids may flow through a channel collinearly before multiple emulsion droplets are formed. The fluidic channels may also, in certain embodiments, include varying degrees of hydrophilicity or hydrophobicity. As examples, the fluidic channel may be relatively hydrophilic upstream of an intersection (or other region within the channel) and relatively hydrophobic downstream of the intersection, or vice versa. In some cases, the average cross-sectional dimension may change, e.g., at an intersection. For instance, the average cross-sectional dimension may increase at the intersection. Surprisingly, a relatively small increase in dimension, in combination with a change in hydrophilicity of the fluidic channel, may delay droplet formation of a stream of collinearly-flowing multiple fluids under certain flow conditions; accordingly, the point at which multiple emulsion droplets are formed can be readily controlled within the fluidic channel. In some cases, the multiple droplet may be formed from the collinear flow of fluids at (or near) a single location within the fluidic channel. In addition, unexpectedly, systems such as those described herein may be used to encapsulate fluids in single or multiple emulsions that are difficult or impossible to encapsulate using other techniques, such as fluids with low surface tension, viscous fluids, or viscoelastic fluids. Other aspects of the invention are generally directed to methods of making and using such systems, kits involving such systems, emulsions created using such systems, or the like.

A foam production method includes mixing liquid nitrogen with a foaming material to produce foam. A gas is produced in situ from liquid nitrogen. As the ratio of the volume of the gas produced by gasification of liquid nitrogen to the volume of the liquid nitrogen is relatively high, when a large gas supply flow is needed to generate a large foam flow, a liquid nitrogen storage device of a small volume can be used instead of bulky air supply devices such as high-pressure gas cylinders, air compressors, air compressor sets and the like, reducing the volume of the air supply device. In addition, the liquid nitrogen used in foaming will release nitrogen gas after the foam blast, such that the nitrogen is also able to inhibit combustion on the surface of burning materials, accelerating the extinguishing of the fire.

A stirrer is provided such that a fluid being processed can be more efficiently shown by way of the action of an intermittent jet flow and processing capacity can be improved. The stirrer concentrically includes a rotor that includes a plurality of flat vanes and that rotates, and a screen that is place around the rotor. The screen includes a plurality of slits in the circumferential direction thereof, and screen members that are positioned between adjacent slits. The fluid being processed is discharged by rotation of the rotor from the inside of the screen to the outside as an intermittent jet flow through the slits. The width of the distal working face on the distal end of the vane in the rotational direction is smaller than the width of the basal end of the vane in the rotational direction.

A stirrer is provided that can more efficiently achieve shearing applied, by an action of an intermittent jet flow, to a fluid to be processed. The stirrer concentrically includes a rotor including a blade, a partition wall, and a screen, wherein: the screen includes a plurality of slits in a circumferential direction thereof and screen members located between the adjacent slit; by rotating at least the rotor of the two components, the fluid to be processed is discharged from the inside to the outside of the screen as the intermittent jet flow through the slit of the screen; the screen has a cylindrical shape having a circular cross section; an opening of the slit provided on the inner wall surface of the screen is used as an inflow opening; openings of the plurality of slits provided on the outer wall surface of the screen are used as outflow openings; and the width of the outflow openings in the circumferential direction is set to be smaller than the width of the inflow opening in the circumferential direction.

Systems, devices, and methods are provided that are useful in generating a fluid suspension of nanoplasmoid bubbles. Such systems utilize a nanobubble/nanoplasmoid generator in conjunction with mechanisms for applying energy to the fluid in the form of electrolytic events, pressure waves, electrical fields, and/or magnetic fields. The nanobubble/nanoplasmoid generator is of modular construction that is readily adaptable to a wide variety of applications. Various applications of nanoplasmoid bubble suspensions so produced are described.

A method of measuring a minimum pressure for gas bubble generation (MPGBG) value of a capillary tube is disclosed. The capillary tube has an inlet and an output portion including an outlet. The inlet is connected to a regulated pneumatic system, configured to supply a gas to the inlet under pressure. The output portion is immersed in a liquid. The gas is supplied to the inlet under a range of pressures including a higher pressure range and a lower pressure range. In the higher pressure range, gas bubbles are generated in the liquid from the outlet. In the lower pressure range, no gas bubbles are generated in the liquid from the outlet. A value of the minimum pressure for gas bubble generation (MPGBG) for the liquid is determined.

Other methods include a method of measuring and storing MPGBG values of capillary tubes, methods of selecting at least one capillary tube from a plurality of capillary tubes, and a method of cutting a capillary tube to a desired MPGBG value.