7 results about "500 kHz" patented technology

The invention discloses a lubricant for drilling fluid and a preparation method of the lubricant, and belongs to the field of oil and gas drilling chemical additives. In the water-based drilling fluid, microbubbles I with the diameter of 0.1-1 mu m and microbubbles II with the diameter of 1-10 mu m are prepared in situ, and a low-frequency sound field of 20-50 kHz and a high-frequency sound field of 200-500 kHz are adopted for alternate or superposed driving; the microbubbles I are rapidly broken to release the lubricant to achieve instantaneous efficient lubrication of the initial drilling section, and the microbubbles II are slowly broken to maintain the lubricating film to achieve lasting lubrication of the rear section. The preparation method comprises the following steps: mixing the base oil, the surfactant, the gas precursor and the foam adjusting aid in proportion, performing synchronous gas injection oscillation in a multi-frequency sound field to form a graded microbubble suspension, and performing settling separation and stabilizing treatment to obtain the product. The lubricant can obviously reduce the friction between a drilling tool and a well wall and prolong the service life of the drilling tool, is compatible with an existing slurry system, is free of waste water and waste gas emission in production, does not detect heavy metals after being used, is easy to degrade in surfactant and pollution-free to underground water, meets the requirement of green drilling, and has excellent engineering popularization value.

A generator with a regeneration device. The electrosurgical generator according to the invention includes an oscillating circuit excited by means of an excitation circuit having a frequency preferably close to its resonant frequency, wherein the oscillation should be periodically interrupted. This can be done, for example, in situations where a pulse-pause modulation of a radio frequency voltage must be created, the fundamental frequency of which, for example, 350 kHz or 500 kHz, can be modulated with a modulation frequency of, for example, 50 kHz. To stop the oscillation in the generator's oscillating circuit as abruptly as possible without losing the energy stored in the oscillating circuit, a regeneration circuit is provided, implemented by means of a voltage multiplier circuit. Compared to a boost converter coupled inductor, it has the advantage of providing a low capacitive load to the oscillating circuit, especially because it is only electrically effectively connected to the oscillating circuit via a switch during the regeneration phase. This concept allows for efficient energy regeneration and therefore allows for precise amplitude modulation of the radio frequency voltage, particularly square wave modulation (on-off-switch).

To provide an ultrasonic element capable of stably outputting ultrasonic waves with frequencies below 500 kHz. [Solution] The ultrasonic element comprises a substrate having a vibrating region and a non-vibrating region surrounding the vibrating region, a first electrode disposed inside the vibrating region, a piezoelectric body disposed on the substrate covering the first electrode, and a second electrode provided on the piezoelectric body, wherein the direction in which the substrate, the first electrode, the piezoelectric body, and the second electrode are stacked is defined as the stacking direction, and the thickness of the substrate along the stacking direction is 2.0 μm or more and 10.0 μm or less.

Electrical therapy applied to the brain with increased efficacy and / or decreased undesirable side effects, and associated systems and methods, are disclosed. A representative method includes applying a therapy signal to a patient, via at least one electrode at a subdural or epidural location at the patient's brain, to provide effective therapy that reduces or eliminates the effects of a patient disorder. The therapy signal does not induce any non-therapeutic side effects, and has a frequency in a frequency range of from 1.2 kHz to 500 kHz, an amplitude in an amplitude range from 0.1 to 20 mA, and a pulse width in a pulse width range from 1 microsecond to 400 microseconds.

A multi-element ultrasonic transducer for examining an object comprises a piezoelectric layer comprising at least one emitting element configured to apply to the object input ultrasound waves having a center frequency lower than or equal to 500 kHz to cause a longitudinal propagation of ultrasonic guided waves along a longitudinal axis of the object, and a plurality of receiving elements spaced from the at least one emitting element, the plurality of receiving elements and the at least one emitting element arranged along the longitudinal axis, the plurality of receiving elements configured to acquire, from the object, acoustic waves produced by the longitudinal propagation of the ultrasonic guided waves.

A system and method for detecting leaks in nuclear fuel pool assemblies utilize ultrasonic technology to provide safety and integrity. The system includes an inner tube with cobalt slugs, surrounded by an outer tube, both submerged in water. Magnets align the slugs, while ultrasonic transducers transmit and receive waves to detect water presence. A pulse generator excites the transducers, and a control circuit analyzes signal changes to identify leaks. The system operates at frequencies between 50 kHz and 500 kHz, with pulse amplitudes from 50 to 500 volts. A spectrum analyzer enhances detection accuracy by evaluating power distribution across frequencies. The method involves aligning slugs, transmitting waves, and analyzing amplitude changes to confirm water ingress, optimizing detection through strategic transducer positioning and signal analysis.

A system (350) and method (400, 500) for detecting leaks in nuclear fuel pool assemblies utilize ultrasonic technology to provide safety and integrity. The system includes an inner tube (306) with cobalt slugs (302), surrounded by an outer tube (312), both submerged in water. Magnets (206) align the slugs, while ultrasonic transducers (204) transmit and receive waves to detect water presence. A pulse generator (328) excites the transducers, and a control circuit (326) analyzes signal changes to identify leaks. The system operates at frequencies between 50 kHz and 500 kHz, with pulse amplitudes from 50 to 500 volts. A spectrum analyzer (340) enhances detection accuracy by evaluating power distribution across frequencies. The method involves aligning slugs, transmitting waves, and analyzing amplitude changes to confirm water ingress, optimizing detection through strategic transducer positioning and signal analysis.