An apparatus for measuring parameters of plasma includes a cutoff probe. The cutoff probe includes: a first antenna having a line shape and configured to emit a microwave to the plasma in response to the signal provided by at least one processor; a second antenna having a line shape and configured to generate an electrical signal in response to receiving the microwave emitted by the first antenna and transferred through the plasma; a first insulating layer; a second insulating layer; a first shield; a second shield; an end protection layer covering an end of each of the first insulating layer, the second insulating layer, the first shield, and the second shield; a first antenna protection layer, of insulating nature, covering the first antenna; and a second antenna protection layer, of insulating nature, covering the second antenna.

Systems and methods include a fluorescence measurement apparatus. A single-wavelength light source generates an excitation light source. A sample holder holds a sample and includes a surface transparent to the excitation light source. Mounts attached to the single-wavelength light source(s) or the sample holder change an incident angle of the excitation light source on the surface. Optical components positioned in a path of a fluorescence emission emitted from the surface guide the fluorescence emission to a detector that obtains spectra from at least first and second angles-of-incidence. A device records spectra obtained by the detector from the first and second angles-of-incidence, normalizes and analyzes intensities of the spectra, subtracts a first spectrum corresponding to the first angle-of-incidence from a second spectrum corresponding to the second angle-of-incidence to obtain a difference, identifying a sample type of the sample based on an API gravity mapped to the difference.

Systems and methods include a fluorescence measurement apparatus. A single-wavelength light source generates an excitation light source. A sample holder holds a sample and includes a surface transparent to the excitation light source. Mounts attached to the single-wavelength light source(s) or the sample holder change an incident angle of the excitation light source on the surface. Optical components positioned in a path of a fluorescence emission emitted from the surface guide the fluorescence emission to a detector that obtains spectra from at least first and second angles-of-incidence. A device records spectra obtained by the detector from the first and second angles-of-incidence, normalizes and analyzes intensities of the spectra, subtracts a first spectrum corresponding to the first angle-of-incidence from a second spectrum corresponding to the second angle-of-incidence to obtain a difference, identifying a sample type of the sample based on an API gravity mapped to the difference.

A fluid sensor includes a tuning fork mechanical resonator including a base and a tine projecting from the base along a longitudinal direction of the tine, and a pair of electrodes disposed on the tine. The base and the tine are formed from a piezoelectric material including lithium tantalate. The electrodes are exposed to a fluid.

The present disclosure provides systems, apparatuses, and methods for measuring submerged surfaces. Embodiments include a measurement apparatus including a main frame, a source positioned outside a pipe and connected to the main frame, and a detector positioned outside the pipe at a location diametrically opposite the source and connected to the main frame. The source may transmit a first amount of radiation. The detector may receive a second amount of radiation, determine a composition of the pipe based on the first and second amounts of radiation, and send at least one measurement signal. A control canister positioned on the main frame or on a remotely operated vehicle (ROV) attached to the apparatus may receive the at least one measurement signal from the detector and convey the at least one measurement signal to software located topside.

The present disclosure provides systems, apparatuses, and methods for measuring submerged surfaces. Embodiments include a measurement apparatus including a main frame, a source positioned outside a pipe and connected to the main frame, and a detector positioned outside the pipe at a location diametrically opposite the source and connected to the main frame. The source may transmit a first amount of radiation. The detector may receive a second amount of radiation, determine a composition of the pipe based on the first and second amounts of radiation, and send at least one measurement signal. A control canister positioned on the main frame or on a remotely operated vehicle (ROV) attached to the apparatus may receive the at least one measurement signal from the detector and convey the at least one measurement signal to software located topside.

A method for calibrating a radiometric device for determining and/or monitoring the density of a medium located in a container includes: determining the count rate of the radioactive radiation after it has passed through the empty container on the basis of the activity of the transmitting unit; determining the measured count rate of the radioactive radiation after it has passed through the container when a calibration medium of known density is located in the container; determining the mass attenuation coefficient according to the formula μ=−(ln(N/N.sub.0))/(ρ.sub.1D), where D is a beam path of the radioactive radiation or inner diameter of the container, and ρ.sub.1 is density of the calibration medium; and calculating a calibration curve representing the dependence of the density of the medium on the count rate of the measured radiation intensity after the radiation has passed through the container.

A method for calibrating a radiometric device for determining and/or monitoring the density of a medium located in a container includes: determining the count rate of the radioactive radiation after it has passed through the empty container on the basis of the activity of the transmitting unit; determining the measured count rate of the radioactive radiation after it has passed through the container when a calibration medium of known density is located in the container; determining the mass attenuation coefficient according to the formula μ=−(ln(N/N.sub.0))/(ρ.sub.1D), where D is a beam path of the radioactive radiation or inner diameter of the container, and ρ.sub.1 is density of the calibration medium; and calculating a calibration curve representing the dependence of the density of the medium on the count rate of the measured radiation intensity after the radiation has passed through the container.

The present disclosure provides systems, apparatuses, and methods for measuring submerged surfaces. Embodiments include a measurement apparatus including a main frame, a source positioned outside a pipe and connected to the main frame, and a detector positioned outside the pipe at a location diametrically opposite the source and connected to the main frame. The source may transmit a first amount of radiation. The detector may receive a second amount of radiation, determine a composition of the pipe based on the first and second amounts of radiation, and send at least one measurement signal. A control canister positioned on the main frame or on a remotely operated vehicle (ROV) attached to the apparatus may receive the at least one measurement signal from the detector and convey the at least one measurement signal to software located topside.

The present disclosure provides systems, apparatuses, and methods for measuring submerged surfaces. Embodiments include a measurement apparatus including a main frame, a source positioned outside a pipe and connected to the main frame, and a detector positioned outside the pipe at a location diametrically opposite the source and connected to the main frame. The source may transmit a first amount of radiation. The detector may receive a second amount of radiation, determine a composition of the pipe based on the first and second amounts of radiation, and send at least one measurement signal. A control canister positioned on the main frame or on a remotely operated vehicle (ROV) attached to the apparatus may receive the at least one measurement signal from the detector and convey the at least one measurement signal to software located topside.