A diffusion cell includes: a donor chamber having bottom; a receptor chamber below and in fluid communication with the donor chamber, and having upper and lower ends; a membrane between and in contact with the bottom of the donor chamber and upper end of the receptor chamber, and adapted to diffuse some of the media in a liquid from the donor chamber to the receptor chamber; a conduit having a first port near the lower end of the receptor chamber and a second port above the first port and near the upper end of the receptor chamber; and a bubble trap in fluid communication with the upper end of the receptor chamber and having a third port higher than the second port; wherein circulation of a flow of fluid through the conduit and the receptor chamber removes bubbles from underneath the membrane and transports bubbles to the bubble trap.

Among other things, the present invention is related to the field of bio/chemical sampling, sensing, assays and other applications.

Apparatuses and methods of measuring a hydrogen diffusivity of a metal structure including during operation of the metal structure, are provided. A hydrogen charging surface is provided at a first location on an external surface of the structure. In addition, a hydrogen oxidation surface is provided at a second location adjacent to the first location on the external surface of the structure. Hydrogen flux is generated and directed into the metal surface at the charging surface. At least a portion of the hydrogen flux generated by the charging surface is diverted back toward the surface. A transient of the diverted hydrogen fluxes measured, and this measurement is used to determine the hydrogen diffusivity of the metal structure in service.

The subject disclosure presents systems and computer-implemented methods for evaluating a tissue sample that has been removed from a subject. A change in speed of the energy traveling through the sample is evaluated to monitor changes in the biological sample during processing. The rate of change in the speed of the energy is correlated with the extent of diffusion. A system for performing the method can include a transmitter that outputs the energy and a receiver configured to detect the transmitted energy. A time-of-flight of acoustic waves and rate of change thereof is monitored to determine an optimal time for soaking the tissue sample in a fixative.

A method for determining the diffusion radius of in-situ injection and remediation of contaminated soil and groundwater. According to the triangle method, the hole spacing is perpendicular to the groundwater flow direction, the row spacing is along the groundwater flow direction, and the flow diffusion in the groundwater during the effective time of the remediation agent reaction is considered. Under high pressure rotary injection, the remediation agent and a certain proportion of bromide ions are simultaneously injected into the aquifer as a tracer. The diffusion of the agent is determined by observing the phenomenon of slurry-returning and slurry-channeling of adjacent injection points. After the completion of the injection, the groundwater is quickly sampled in fixed depth, the tracer concentration is quickly detected on site, and the concentration of bromide ions in the groundwater is compared with the background value. Comprehensive determination determines the optimal diffusion radius.

A diffusion system to improve the efficiency, accuracy, and consistency of testing the release rate of an active ingredient in semisolid form through a membrane in between a dosage lid and a cell cap mounted on a cell in which a mixer is placed to mix the receptor medium in the cell as the semisolid diffuses through the membrane. The cell can be placed in a heating system to heat the samples. The cell has a sampling arm through which samples of the receptor medium can be extracted without opening the cell cap and dosage lid. The mixer may be cylindrical and may occupy a large surface area of the cell. The mixer may have grooves and other irregularities to increase turbulence while mixing. The system can be automated using an automated sampling and collection station.

The invention refers to an in vitro method and apparatus for analysing the behaviour of substances in simulated physiological environment. The method comprises the steps of providing a first fluid, a gel matrix and a second fluid, separating the first fluid and the gel matrix by at least one first semi-permeable membrane and separating the gel matrix and the second fluid by at least one second semi-permeable membrane. The method further comprises the steps of injecting a substance into the first fluid, letting the substance migrate from the first fluid through the at least one first semi-permeable membrane, through the gel matrix, through the at least one second semi-permeable membrane and into the second fluid, and determining clearance of the substance from the first fluid.

Apparatuses and methods of measuring a hydrogen diffusivity of a metal structure including during operation of the metal structure, are provided. A hydrogen charging surface is provided at a first location on an external surface of the structure. In addition, a hydrogen oxidation surface is provided at a second location adjacent to the first location on the external surface of the structure. Hydrogen flux is generated and directed into the metal surface at the charging surface. At least a portion of the hydrogen flux generated by the charging surface is diverted back toward the surface. A transient of the diverted hydrogen fluxes measured, and this measurement is used to determine the hydrogen diffusivity of the metal structure in service.

The subject disclosure presents systems and computer-implemented methods for evaluating a tissue sample that has been removed from a subject. A change in speed of the energy traveling through the sample is evaluated to monitor changes in the biological sample during processing. The rate of change in the speed of the energy is correlated with the extent of diffusion. A system for performing the method can include a transmitter that outputs the energy and a receiver configured to detect the transmitted energy. A time-of-flight of acoustic waves and rate of change thereof is monitored to determine an optimal time for soaking the tissue sample in a fixative.

A diffusion cell is described that includes a receiver compartment and a tightening ring intended to be positioned above the receiver compartment in such a way that a membrane sample, such as a sample of a skin, can be arranged between the receiver compartment and the tightening ring. The cell further includes means for tightening by rotation of the tightening ring on the receiver compartment. Uses of such a diffusion cell, in particular for evaluating the penetration capacity of a compound of interest contained in an aerosol formulation, are also described. These uses can be applicable in an occlusive patch or semi-occlusive patch or in a formulation under occlusive or semi-occlusive conditions in the skin. The uses can also be implemented to evaluate the capacity of an aerosol formulation, an occlusive or semi-occlusive patch or a formulation under occlusive or semi-occlusive conditions to deliver a compound of interest through the skin.