A method and corresponding device are provided for determining a flow speed in a fluid conduit. The fluid conduit is provided with first, second and third ultrasonic wet transducers, wherein respective connection lines between transducers extend outside of a direction of average flow of the fluid conduit. First and second measuring signals are applied to the first ultrasonic wet transducer and received at the second and the third ultrasonic wet transducer, respectively. The measuring signals comprise a respective reversed signal portion with respect to time of a response signal. Respective first and second response signals are measured and the flow speed is derived from at least one of the first and second response signals.

Disclosed is a characterization method of closed pores and connectivity of coal measure composite reservoirs, including collecting samples of coal seams and shales reservoirs, carrying out low-field NMR experiments and NMR freeze-thaw experiments on plunger samples and crushed samples with different particle sizes to obtain cumulative pore volume distribution and differential pore size distribution of the crushed samples, comparing crushed samples with plunger samples for optimal crushed particle sizes, and preliminarily determining a distribution range of closed pores; carrying out SAXS experiments on crushed samples to obtain size distribution and volume of total pores of 1-100 nanometers; calculating pore volume of total pores and closed pore volume in composite reservoirs by low-field NMR experiments results; carrying out non-steady overburden permeability experiments and variable factors on plunger samples of coal seams, shales and tight sandstone to characterize the connectivity under influence of pores development and lithologic combinations.

An example system is configured to detect saturation levels of a target, such as a core sample of a reservoir, using magnetic fields generated by hydrophilic magnetic nanoparticles within the target. The target contains both a hydrocarbon, such as oil or gas, and a mixture comprised of water and the hydrophilic magnetic nanoparticles. The system includes magnetic field detectors for spatial distribution across a dimension of the target. The magnetic field detectors are configured to detect a magnetic field associated with the hydrophilic magnetic nanoparticles. A data processing system is configured—for example, programmed—to determine a saturation profile of the target based on the magnetic field.

The present disclosure provides a multi-layer open channel portable flow measuring device based on a water impulse principle and a flow measuring method; an instantaneous water head height of a water-carrying section, namely, a water level H is measured through a pressure sensor at a bottom of a U-shaped hollow tube; at the same time, layered multi-point velocity measuring components in equidistant layout include a series of position “current meters” composed of tension sensors, hollow punching lightweight steel balls and lightweight elastic steel ropes to measure velocities V.sub.1-n of different points, n depends on the layer decided to be arranged according to a channel depth, an instantaneous flow value of the whole water-carrying section is further acquired through multi-layer flow accumulation, and with a simple structure, intelligent control, easy operation and convenient carrying, the present disclosure may further improve the flow measuring precision.

The invention relates to the field of detection of implantable medical devices, particularly to magnetically induced torque measurement devices and method of implants in magnetic resonance imaging systems. The measurement device includes transmission shafts, gear sets, a knob, an indicator, a detachable torsion spring set, a loading tray, a protractor, and an MRI-compatible camera. The measurement device changes its measurement range by replacing the detachable torsion spring set, adjusts a height of the loading tray by a lifting platform, amplifies a rotation angle of the knob by the gear sets, and records deflection angles of the loading tray by the MRI-compatible camera. The measurement device provides the detachable torsion spring set, which is suitable for measuring most samples; and provides a height-adjustable loading tray, which can be applied to MR systems with different center heights.

Through discrimination of the scattered signal polarization state, a lidar system measures a distance through semi-transparent media by the reception of single or multiple scattered signals from a scattering medium. Combined and overlapped single or multiple scattered light signals from the medium can be separated by exploiting varying polarization characteristics. This removes the traditional laser and detector pulse width limitations that determine the system's operational bandwidth, translating relative depth measurements into the conditions of two surface timing measurements and achieving sub-pulse width resolution.

The present disclosure provides a high-frequency magnetoimpedance testing apparatus and method. A testing platform in the apparatus is arranged within a Helmholtz coil and connected to a modulating electric current source and a high-frequency impedance analyzer, respectively; the Helmholtz coil is connected to a DC power source; a processor is connected to the high-frequency impedance analyzer and the DC power source separately; the testing platform includes a first double-sided copper-clad plate, and mode transition switches and connection terminals that are arranged on the first double-sided copper-clad plate; one end of the first double-sided copper-clad plate is connected to the high-frequency impedance analyzer, while the other end of the same is connected to a load; the mode transition switches are connected to the modulating electric current source. The present disclosure can realize in-situ current modulation of metallic fibers and high-frequency magnetoimpedance testing, and improve the testing accuracy.

A method for completing a wellbore traversing a subterranean formation includes making electromagnetic resistivity measurements along a lateral section of the wellbore. The resistivity measurements are evaluated to estimate a water content of the subterranean formation along the lateral section. The formation is fractured at selected regions along the lateral section at which the water content is below a threshold and avoiding regions at which the water content is above the threshold.

Methods and systems are provided that use resistivity log data to estimate water saturation of formation rock and/or other useful formation parameters (such as CEC) in a manner that accounts for one or more electrically conductive mineral components contained in the formation rock.

A method for measuring oil-water distribution using DNP-MRI, comprising adding a free radical for DNP enhanced NMR signal of a water phase or an oil phase in a sample containing oil and water; performing an MRI experiment on the sample, and collecting an MRI image of the sample without DNP enhancement; applying microwave excitation for DNP-MRI experiment under the same MRI experiment condition as step 2, and collecting an MRI image of the sample after DNP enhancement; and comparing the MRI image after DNP enhancement with the MRI image without DNP enhancement. In the MRI image with DNP enhancement, an area with enhanced MRI signal intensity is a selectively enhanced fluid phase distribution area, and an area without obviously changed MRI signal intensity is a non-selectively enhanced fluid phase distribution area. The method is simple, convenient to operate, short in measurement time, and high in measurement efficiency.