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.

A contact angle measurement apparatus includes a liquid reservoir arrangement, a drop dosing device in fluid communication with the liquid reservoir arrangement and adapted for applying a liquid drop onto a sample surface, an illuminating device for illuminating each drop applied by the drop dosing device and disposed on the surface from a first side, and an image recording device for recording an image of each applied drop disposed on the surface. A liquid pressurizing system is adapted to pressurize liquid from the liquid reservoir arrangement, and a controller connected to the valve of each drop dosing device and to the liquid pressurizing system, which controls the operation of the liquid pressurizing system and, for each drop dosing device, opening and closing of the respective valve to apply a drop of the respective liquid from the respective liquid line to the surface in a jet of pressurized liquid.

A titration module includes a base, at least one titration unit, a contact angle measuring module, and a computing unit. The at least one titration unit is disposed above the base for titrating a globule onto a device under test. The contact angle measurement module is disposed above the base for measuring a first height and a first radius of the globule. The computing unit can calculate a second radius according to the first height and the first radius, and can calculate a contact angle of the globule according to the first height and the second radius. Also disclosed are a test apparatus, and a method for measuring titration contact angles.

A method for determining a contact angle of a hydrocarbon on a rock surface, the method including injecting a first brine fluid into a test cell, the first brine fluid having an initial ionic composition, injecting a hydrocarbon fluid into the test cell, contacting the hydrocarbon fluid with the first brine fluid, forming a droplet, measuring the contact angle of the hydrocarbon fluid, at least partially displacing the first brine fluid with an inert gas, measuring a ionic composition of the displaced first brine fluid in an ionic chromatograph, and comparing the measured ionic composition to the initial ionic composition.

A magnetic pole part, a fiber-reinforced material, a test apparatus therefor, and a control method for the test apparatus. The test apparatus comprises: a container provided with an adhesive agent container therein for containing an adhesive agent; a positioning member for positioning a member to be tested inside the container and partially inside the adhesive agent container; an adhesive agent heating member 912) for heating the adhesive agent; and an adhesive agent temperature sensor for measuring the temperature of the adhesive agent; a controller for turning on or off the adhesive agent heating member according to a temperature signal detected by the adhesive temperature sensor so as to keep the adhesive agent in the adhesive agent container at a preset temperature.

A contact angle measurement system includes a housing that can hold a volume of a first fluid having a first density, an adjustable rock sample holder positioned within the housing, a fluid dropper attached to the housing, an image capturing a device, and a computer system. The holder can support a rock sample. An orientation of the holder relative to the housing is adjustable such that an outer surface of the rock sample is at a non-zero angle relative to a lower wall of the housing. When the orientation of the holder relative to the housing is such that the outer surface of the rock sample is at the non-zero angle relative to the lower wall, the fluid droplet traverses the outer surface of the rock sample. The image capturing device can capture images of the fluid droplet as the fluid droplet traverses the outer surface of the rock sample.

Disclosed is a method for measuring surface tension based on an axisymmetric droplet contour curve. The method comprises: photographing a suspended droplet image, and extracting a droplet contour curve; selecting a measurement point on the droplet contour curve; and calculating the surface tension of a liquid using the following formula

[00001]$\sigma =\frac{\mathrm{\Delta \rho }\mathrm{gV}+P\pi R^2}{2\pi R\sin \left(\theta \right)},$

wherein σ is the surface tension of the liquid, Δρ is the density difference between the liquid and the atmosphere, g is the local gravitational acceleration, P is the pressure at the cross section of the droplet cut from a horizontal plane of the measurement point, R is the radius of a circular surface formed by cutting the droplet, θ is the inclination angle between the tangent line of the measurement point on the droplet and the horizontal plane, and V is the droplet volume at the lower part of the cross section of the droplet.

A method for determining rock wettability based on contact angle measurement and correction of multiple oil globules includes: saturating a rock sample with oil, placing a shooting angle calibration circle on a measurement surface of the rock sample, and placing the rock sample saturated with oil in water for water imbibition and oil displacement to form a rock sample with multiple oil globules; acquiring an image of a measurement surface of the rock sample with multiple oil globules at a shooting angle α and a deformation degree of the calibration circle in a shooting field of view, and calculating the shooting angle α; correcting, based on the shooting angle α, a contact angle measurement value γ through a contact angle correction model to acquire a contact angle correction value θ; and determining, based on the contact angle correction value θ, wettability of the rock sample.

A surface wettability determination system includes a sprayer, a light emission device and an optical detector. The sprayer is provided to spray a liquid on a detected surface of a detected object. The light emission device is provided to emit a light beam toward the detected surface. The light beam is reflected by the liquid on the detected surface to generate a reflected light. The optical detector is provided to receive the reflected light and output a determining signal, and the determining signal is related to a wettability of the detected surface.

A method includes saturating a core sample with a hydrocarbon fluid to provide a hydrocarbon-saturated core, placing the core into a first aqueous fluid, applying an external force at increasing magnitude to the hydrocarbon-saturated core to displace a volume of the hydrocarbon fluid in the hydrocarbon-saturated core with the first aqueous fluid at each pressure magnitude, measuring a volume of displaced hydrocarbon fluid at each pressure magnitude, obtaining a first capillary pressure curve, re-saturating the core sample, placing the hydrocarbon-saturated core into a second aqueous fluid having a wettability altering agent, applying an external force at increasing magnitude to displace a volume of the hydrocarbon fluid in the core with the second aqueous fluid at each pressure magnitude, measuring a volume of displaced hydrocarbon fluid at each pressure magnitude, obtaining a second capillary pressure curve, and calculating a contact angle of the second aqueous fluid.