Lead zirconate titanateLead zirconate titanate, also called lead zirconium titanate and commonly abbreviated as PZT, is an inorganic compound with the chemical formula It is a ceramic perovskite material that shows a marked piezoelectric effect, meaning that the compound changes shape when an electric field is applied. It is used in a number of practical applications such as ultrasonic transducers and piezoelectric resonators. It is a white to off-white solid. Lead zirconium titanate was first developed around 1952 at the Tokyo Institute of Technology.
Galleria mellonellaGalleria mellonella, the greater wax moth or honeycomb moth, is a moth of the family Pyralidae. G. mellonella is found throughout the world. It is one of two species of wax moths, with the other being the lesser wax moth. G. mellonella eggs are laid in the spring, and they have four life stages. Males are able to generate ultrasonic sound pulses, which, along with pheromones, are used in mating. The larvae of G. mellonella are also often used as a model organism in research.
Ultrasonic cleaningUltrasonic cleaning is a process that uses ultrasound (usually from 20 to 40 kHz) to agitate a fluid, with a cleaning effect. Ultrasonic cleaners come in a variety of sizes, from small desktop units with an internal volume of less than , to large industrial units with volumes approaching 1,000 litres (260 US gal). The principle of the ultrasonic cleaning machine is to convert the sound energy of the ultrasonic frequency source into mechanical vibration through the transducer.
Contrast agentA contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. Contrast agents absorb or alter external electromagnetism or ultrasound, which is different from radiopharmaceuticals, which emit radiation themselves. In x-ray imaging, contrast agents enhance the radiodensity in a target tissue or structure. In magnetic resonance imaging, contrast agents shorten (or in some instances increase) the relaxation times of nuclei within body tissues in order to alter the contrast in the image.
Length measurementLength measurement, distance measurement, or range measurement (ranging) refers to the many ways in which length, distance, or range can be measured. The most commonly used approaches are the rulers, followed by transit-time methods and the interferometer methods based upon the speed of light. For objects such as crystals and diffraction gratings, diffraction is used with X-rays and electron beams. Measurement techniques for three-dimensional structures very small in every dimension use specialized instruments such as ion microscopy coupled with intensive computer modeling.
Surface acoustic waveA surface acoustic wave (SAW) is an acoustic wave traveling along the surface of a material exhibiting elasticity, with an amplitude that typically decays exponentially with depth into the material, such that they are confined to a depth of about one wavelength. SAWs were first explained in 1885 by Lord Rayleigh, who described the surface acoustic mode of propagation and predicted its properties in his classic paper. Named after their discoverer, Rayleigh waves have a longitudinal and a vertical shear component that can couple with any media like additional layers in contact with the surface.
Doppler fetal monitorA Doppler fetal monitor is a hand-held ultrasound transducer used to detect the fetal heartbeat for prenatal care. It uses the Doppler effect to provide an audible simulation of the heart beat. Some models also display the heart rate in beats per minute (BPM). Use of this monitor is sometimes known as Doppler auscultation. The Doppler fetal monitor is commonly referred to simply as a Doppler or fetal Doppler. It may be classified as a form of Doppler ultrasonography (although usually not technically -graphy but rather sound-generating).
GE HealthCareGE HealthCare Technologies Inc., doing business as GE HealthCare, is an American multinational medical technology company headquartered in Chicago, Illinois. It was spun-off from General Electric on January 4, 2023, with GE retaining 20%. As of 2017, it is a manufacturer and distributor of diagnostic imaging agents and radiopharmaceuticals for imaging modalities used in medical imaging procedures.
Acoustic levitationAcoustic levitation is a method for suspending matter in air against gravity using acoustic radiation pressure from high intensity sound waves. It works on the same principles as acoustic tweezers by harnessing acoustic radiation forces. However acoustic tweezers are generally small scale devices which operate in a fluid medium and are less affected by gravity, whereas acoustic levitation is primarily concerned with overcoming gravity.
Sonic weaponSonic and ultrasonic weapons (USW) are weapons of various types that use sound to injure or incapacitate an opponent. Some sonic weapons make a focused beam of sound or of ultrasound; others produce an area field of sound. military and police forces make some limited use of sonic weapons. Extremely high-power sound waves can disrupt or destroy the eardrums of a target and cause severe pain or disorientation. This is usually sufficient to incapacitate a person. Less powerful sound waves can cause humans to experience nausea or discomfort.