Systems, methods, and computer program products for measurement of surface properties using a mobile device are described, the surface properties including interfacial (surface) tension, contact angle (static, advancing, or receding), solid surface energy, and rolling or sliding angle on an inclined surface. The system has a support adapted to receive a mobile device with a camera and a processor. A structure is coupled to the support that is adapted to removably receive measurement components. The measurement components are configurable to place a droplet or a bubble within a field of view of the camera. Software on the mobile device is configured to operate the camera to take an image of the droplet or the bubble within the field of view of the camera, and to determine one or more physical properties of the droplet or the bubble based on an analysis of the image.

Systems, methods, and computer program products for measurement of surface properties using a mobile device are described, the surface properties including interfacial (surface) tension, contact angle (static, advancing, or receding), solid surface energy, and rolling or sliding angle on an inclined surface. The system has a support adapted to receive a mobile device with a camera and a processor. A structure is coupled to the support that is adapted to removably receive measurement components. The measurement components are configurable to place a droplet or a bubble within a field of view of the camera. Software on the mobile device is configured to operate the camera to take an image of the droplet or the bubble within the field of view of the camera, and to determine one or more physical properties of the droplet or the bubble based on an analysis of the image.

An analysis apparatus includes a detector and a determination unit. The detector detects, for a target particle, a direction of a surface that is in proximity to the target particle. The determination unit determines the target particle to be a surface particle in a case where the number of other particles within a predetermined region extending in the direction of the surface is smaller than a threshold.

Aspects of the invention include determining, by a first AFM tip, a first snap-off force of a solid surface immersed in a first fluid, determining, by a second AFM tip, a second snap-off force, determining, by a third AFM tip, a third snap-off force, determining, by the first AFM tip, a fourth snap-off force of a droplet of the first fluid immersed in the second fluid on the solid surface, determining, by the second AFM tip, a fifth snap-off force, determining, by the third AFM tip, a sixth snap-off force, determining a first capillary force for first AFM tip and first droplet based on first snap-off force and fourth snap-off force, determining a second capillary force for second AFM tip and first droplet and a third capillary force for third AFM tip and first droplet, and determining interfacial tension between first fluid and second fluid based on the capillary forces.

Aspects of the invention include determining, by a first AFM tip, a first snap-off force of a solid surface immersed in a first fluid, determining, by a second AFM tip, a second snap-off force, determining, by a third AFM tip, a third snap-off force, determining, by the first AFM tip, a fourth snap-off force of a droplet of the first fluid immersed in the second fluid on the solid surface, determining, by the second AFM tip, a fifth snap-off force, determining, by the third AFM tip, a sixth snap-off force, determining a first capillary force for first AFM tip and first droplet based on first snap-off force and fourth snap-off force, determining a second capillary force for second AFM tip and first droplet and a third capillary force for third AFM tip and first droplet, and determining interfacial tension between first fluid and second fluid based on the capillary forces.

The properties of a fluid body in the form of a surface-attached droplet/bubble can be determined. A data set is stored describing a plurality of droplets/bubbles of different shapes; each shape is captured as a combination of two or more linear dimensional measurements. For each shape the data set includes one or more parameters describing the relationship between the physical properties of a pair of fluids capable of forming that shape as a surface-attached droplet/bubble disposed in a surrounding fluid medium. A fluid body is provided in the form of a surface-attached droplet/bubble and a plurality of linear dimensional measurements are taken and provided as input to a processing apparatus. Processing apparatus determines from the data set the one or more parameters associated with the shape described by said linear dimensional measurements. Particular the surface tension of a fluid can be found in this way based on simple dimensional measurements.

The properties of a fluid body in the form of a surface-attached droplet/bubble can be determined. A data set is stored describing a plurality of droplets/bubbles of different shapes; each shape is captured as a combination of two or more linear dimensional measurements. For each shape the data set includes one or more parameters describing the relationship between the physical properties of a pair of fluids capable of forming that shape as a surface-attached droplet/bubble disposed in a surrounding fluid medium. A fluid body is provided in the form of a surface-attached droplet/bubble and a plurality of linear dimensional measurements are taken and provided as input to a processing apparatus. Processing apparatus determines from the data set the one or more parameters associated with the shape described by said linear dimensional measurements. Particular the surface tension of a fluid can be found in this way based on simple dimensional measurements.

A testing device determines the presence of substances on a surface using a sensor positioned at a known vantage point to the surface. A liquid dispenser deposits a liquid drop on the surface. A data generator after a first time interval for allowing the liquid drop to stabilize on the surface detects, via the sensor, a geometric characteristic of the liquid drop that is related to a first equilibrium contact angle of the liquid drop to the surface. The data generator after a second time interval detects via the sensor the geometric characteristic of the liquid drop that is related to a second equilibrium contact angle. The data generator compares the first and second contact angle and determines a contamination on the surface that is soluble in the liquid drop in response to a change between the first and second contact angles.

Methods, apparatus, and kits for detecting and optionally quantifying amphiphilic compounds in the environment, in media samples, and on objects by determining an initial surface energy of a surface of a sample substrate, exposing the sample substrate surface to a medium that contains or is suspected to contain an amphiphilic compound for a time sufficient for the amphiphilic compound to interact with the sample substrate surface, determining a post-exposure surface energy of the surface of the sample substrate, determining a change in the surface energy of the sample substrate surface, and correlating the determined change in surface energy of the sample substrate surface with a presence and/or character of amphiphilic compounds in the medium.

Methods, apparatus, and kits for detecting and optionally quantifying amphiphilic compounds in the environment, in media samples, and on objects by determining an initial surface energy of a surface of a sample substrate, exposing the sample substrate surface to a medium that contains or is suspected to contain an amphiphilic compound for a time sufficient for the amphiphilic compound to interact with the sample substrate surface, determining a post-exposure surface energy of the surface of the sample substrate, determining a change in the surface energy of the sample substrate surface, and correlating the determined change in surface energy of the sample substrate surface with a presence and/or character of amphiphilic compounds in the medium.