There is provided a state detection method for detecting an oil film state according to a lubricant in a device configured to lubricate a plurality of parts with the lubricant, the method including: a measurement step of measuring impedance and a phase angle of an electric circuit by applying an AC voltage to the electric circuit configured with the plurality of parts while changing a frequency; and a derivation step of deriving an oil film thickness according to the lubricant and a parameter indicating an electrical characteristic according to the oil film thickness, based on a relative dielectric constant at a high frequency limit of the lubricant defined based on a composition of the lubricant, and the impedance and the phase angle measured in the measurement step.

Disclosed herein is a method to evaluate the stability of a protein-based formulation including a protein, a peptide and/or a protein derivative and a buffer relative to a lubricant of a lubricated container in which the formulation is intended to be stored, including: a) Evaluating a decrease over time of interfacial tension between the buffer and the lubricant, b) Evaluating a decrease over time of interfacial tension between the protein-based formulation and the lubricant, c) Identifying at least one component of the protein-based formulation interacting with the lubricant by comparing the decrease evaluated in step b) with the decrease evaluated in step a).

Disclosed herein is a method to evaluate the stability of a protein-based formulation including a protein, a peptide and/or a protein derivative and a buffer relative to a lubricant of a lubricated container in which the formulation is intended to be stored, including: a) Evaluating a decrease over time of interfacial tension between the buffer and the lubricant, b) Evaluating a decrease over time of interfacial tension between the protein-based formulation and the lubricant, c) Identifying at least one component of the protein-based formulation interacting with the lubricant by comparing the decrease evaluated in step b) with the decrease evaluated in step a).

A system and a method are provided for calculating the cetane number, pour point, cloud point, aniline point, aromaticity, and/or octane number of a crude oil and its fractions from the density and fluorescence spectroscopy of a sample of the crude oil.

A system and a method are provided for calculating the cetane number, pour point, cloud point, aniline point, aromaticity, and/or octane number of a crude oil and its fractions from the density and fluorescence spectroscopy of a sample of the crude oil.

Methods are provided for in-situ detection of varnish and/or deposit precursors in a lubricant in a lubricating environment. An electrostatic accumulator can be used within a lubricating environment to enhance accumulation of varnish and/or deposit precursors on portions of the electrostatic accumulator. The deposits accumulated on the electrostatic accumulator can then be characterized in-situ. The potential difference across portions of the electrostatic accumulator can cause an enhanced rate of deposit accumulation on the electrostatic accumulator, which can facilitate characterization of the tendency of a lubricant to accumulate deposits in the lubricating environment.

Methods are provided for in-situ detection of varnish and/or deposit precursors in a lubricant in a lubricating environment. An electrostatic accumulator can be used within a lubricating environment to enhance accumulation of varnish and/or deposit precursors on portions of the electrostatic accumulator. The deposits accumulated on the electrostatic accumulator can then be characterized in-situ. The potential difference across portions of the electrostatic accumulator can cause an enhanced rate of deposit accumulation on the electrostatic accumulator, which can facilitate characterization of the tendency of a lubricant to accumulate deposits in the lubricating environment.

The present invention relates to an experimental device for testing the lubricity in horizontal well drilling with a cuttings bed taken into consideration, which comprises a simulated wellbore with a pulley provided at one end and a hydraulic cylinder fixed and a drill rod mounted at the other end; a cuttings feeding port is arranged above the simulated wellbore; a low end of the simulated wellbore is connected with a liquid return pipeline; the simulated wellbore is provided with an ultrasonic probe and is connected with a rock core holder. The present invention is in line with the actual operating conditions because it not only takes consideration of the friction force between the drill string and the drilling fluid, wellbore wall and slurry cake, but also takes consideration of the friction force between the drill string and the cuttings bed.

The present invention relates to an experimental device for testing the lubricity in horizontal well drilling with a cuttings bed taken into consideration, which comprises a simulated wellbore with a pulley provided at one end and a hydraulic cylinder fixed and a drill rod mounted at the other end; a cuttings feeding port is arranged above the simulated wellbore; a low end of the simulated wellbore is connected with a liquid return pipeline; the simulated wellbore is provided with an ultrasonic probe and is connected with a rock core holder. The present invention is in line with the actual operating conditions because it not only takes consideration of the friction force between the drill string and the drilling fluid, wellbore wall and slurry cake, but also takes consideration of the friction force between the drill string and the cuttings bed.

A lubricity tester unit may comprise a housing, a shaft, wherein a first end of the shaft is disposed at a first end of the housing, wherein the shaft extends through housing along a central axis of the housing, and an encoder, wherein the encoder is disposed on an internal wall of the housing, wherein the shaft is disposed through a hole in the encoder, wherein the encoder is an optical encoder configured to measure angular position of the shaft. The lubricity tester unit may further comprise rotating rings, wherein the rotating rings are coupled to a second end of the shaft, a friction inducing surface, wherein the friction inducing surface is disposed around the rotating rings, a first sensor, wherein the first sensor is disposed through the housing, and a second sensor, wherein the second sensor is disposed through the housing.