A technique facilitates detection and analysis of constituents, e.g. chemicals, which may be found in formation fluids and/or other types of fluids. The technique comprises intermittently introducing a first fluid and a second fluid into a channel in a manner which forms slugs of the first fluid separated by the second fluid. The intermittent fluids are flowed through the channel to create a mixing action which mixes the fluid in the slugs. The mixing increases the exchange, e.g. transfer, of the chemical constituent between the second fluid and the first fluid. The exchange aids in sensing an amount of the chemical or chemicals for analysis. In many applications, the intermittent introduction, mixing, and measuring can be performed in a subterranean environment.

The present invention discloses polymer surfaces with T-shaped microstructure and their fabrication method and applications. The polymer surfaces with the T-shaped microstructure are characterized in that T-shaped microposts arrange orderly on them, and nanobulges arrange orderly on the top surfaces of the micronails of the T-shaped microposts. A flexible insert is designed and manufactured according to the geometry of the T-shaped microposts, and nanogrooves are manufactured on the cavity surface of an injection mold according to the geometry of the nanobulges on the top surfaces of the micronails. The flexible insert is mounted on the injection mold cavity. An injection molding machine is used to inject the molten polymer into the injection mold cavity. Then the polymer surfaces with the T-shaped microposts, on the top surfaces of the micronails of which the nanobulges arrange orderly, are molded. The polymer surfaces with the T-shaped microstructure exhibit robust Cassie-Baxter state and moderate surface adhesion to water droplets, and can be used for quantitative collection, lossless transportation or micromixing of microdroplets.

A microchannel device includes: an upstream channel portion configured to allow an upstream liquid plug and a gas to flow therethrough; a downstream channel portion configured to allow a downstream liquid plug and a gas to flow therethrough; a liquid holding portion provided between a downstream end portion of the upstream channel portion and an upstream end portion of the downstream channel portion, the liquid holding portion being configured to hold a main liquid plug therein; and a gas bypass channel portion provided so as to bypass the liquid holding portion from the downstream end portion of the upstream channel portion to the upstream end portion of the downstream channel portion, the gas bypass channel portion being configured to allow the gas to flow therethrough in a state in which the liquid holding portion holds the main liquid plug.

A technique facilitates detection and analysis of constituents, e.g. chemicals, which may be found in formation fluids and/or other types of fluids. The technique comprises intermittently introducing a first fluid and a second fluid into a channel in a manner which forms slugs of the first fluid separated by the second fluid. The intermittent fluids are flowed through the channel to create a mixing action which mixes the fluid in the slugs. The mixing increases the exchange, e.g. transfer, of the chemical constituent between the second fluid and the first fluid. The exchange aids in sensing an amount of the chemical or chemicals for analysis. In many applications, the intermittent introduction, mixing, and measuring can be performed in a subterranean environment.

Devices and methods for generating droplets. An exemplary device comprises a substantially planar base portion including a bottom surface having a plurality of microfluidic channels formed therein as recessed regions of the bottom surface. The device also comprises a plurality of protrusions projecting from a top surface of the base portion and each formed integrally with the base portion. The device further comprises a sample well, a carrier well, and a droplet well. Each well has an upper portion created by one of the protrusions. A cover layer is attached to the bottom surface of the base portion and seals a bottom side of each microfluidic channel.

A droplet generator apparatus and droplet generation method based on high aspect ratio induced droplet self-breakup are provided. The droplet generator apparatus includes a channel (1) and a nozzle (2) connected to the channel(1), and the aspect ratio of the channel (1) can be 3.0 or greater. The apparatus may further include a blocking rail (10) that is positioned in front of the nozzle (2), a supplying rail(9) that is positioned in front of the nozzle (2), and a supplying trench (8) formed in a space between the nozzle (2) and the supplying rail (9).

The present invention generally relates to systems and methods for the control of fluids and, in some cases, to systems and methods for flowing a fluid into and/or out of other fluids. As examples, fluid may be injected into a droplet contained within a fluidic channel, or a fluid may be injected into a fluidic channel to create a droplet. In some embodiments, electrodes may be used to apply an electric field to one or more fluidic channels, e.g., proximate an intersection of at least two fluidic channels. For instance, a first fluid may be urged into and/or out of a second fluid, facilitated by the electric field. The electric field, in some cases, may disrupt an interface between a first fluid and at least one other fluid. Properties such as the volume, flow rate, etc. of a first fluid being urged into and/or out of a second fluid can be controlled by controlling various properties of the fluid and/or a fluidic droplet, for example curvature of the fluidic droplet, and/or controlling the applied electric field.

Method of detecting a signal from droplets for instrument calibration. In the method, a calibration standard for a droplet detection instrument may be received. The calibration standard may have been shipped at least one kilometer when received. The calibration standard may include a mixture of first droplets and second droplets. Each of the first and second droplets may be encapsulated by an immiscible carrier liquid and may have a stabilizing droplet skin that is formed by heating and that includes a skin-forming protein. Each the first droplets may contain a fluorescent dye, and each of the second droplets may contain a fluorescent dye. A fluorescence signal may be detected from a plurality of the first and second droplets with a droplet detection instrument. The fluorescence signal may be stronger for the first droplets than the second droplets.