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Ultrasound (other)
Ultrasound is sound with frequencies greater than 20 kHz. This frequency is the approximate upper audible limit of human hearing. Ultrasound or ultrasonic may also refer to: Imaging and measurement *Medical ultrasonography, an ultrasound-based diagnostic imaging technique *Ultrasound computer tomography, utilizing ultrasound waves as physical phenomenon for imaging *Ultrasound tongue imaging, imaging technique *Ultrasound transmission tomography, a form of tomography involving ultrasound Media and art *Ultra-Sonic (band), a Scottish dance group *Ultrasonic (film), ''Ultrasonic'' (film), a 2012 American independent film *Ultrasound (film), ''Ultrasound'' (film), a 2021 American science fiction film *Ultrasonics (journal), ''Ultrasonics'' (journal), a bimonthly peer reviewed scientific journal *Ultrasound (band), a rock band Other uses *Ultrasonic antifouling, a technology that helps reduce fouling on underwater structures *Ultrasonic cavitation device, a surgical device to d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasound
Ultrasound is sound waves with frequency, frequencies higher than the upper audible limit of human hearing range, hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies from person to person and is approximately 20 Hertz, kilohertz (20,000 hertz) in healthy young adults. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz. Ultrasound is used in many different fields. Ultrasonic devices are used to detect objects and measure distances. Ultrasound imaging or sonography is often used in medicine. In the nondestructive testing of products and structures, ultrasound is used to detect invisible flaws. Industrially, ultrasound is used for cleaning, mixing, and accelerating chemical processes. Animals such as bats and porpoises use ultrasound for locating Predation, prey and obstacles. History Acoustics, the science of sound, starts as far back as Pyth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Drug Delivery
Sonodynamic therapy (SDT) is a noninvasive treatment, often used for tumor irradiation, that utilizes a sonosensitizer and the deep penetration of ultrasound to treat lesions of varying depths by reducing target cell number and preventing future tumor growth. Many existing cancer treatment strategies cause systemic toxicity or cannot penetrate tissue deep enough to reach the entire tumor; however, emerging ultrasound stimulated therapies could offer an alternative to these treatments with their increased efficiency, greater penetration depth, and reduced side effects. Sonodynamic therapy could be used to treat cancers and other diseases, such as atherosclerosis, and diminish the risk associated with other treatment strategies since it induces cytotoxic effects only when externally stimulated by ultrasound and only at the cancerous region, as opposed to the systemic administration of chemotherapy drugs. Reactive oxygen species (ROS) are an essential component of SDT as they provi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Welding
Ultrasonic welding is an industrial process whereby high-frequency ultrasonic acoustic vibrations are locally applied to work pieces being held together under pressure to create a solid-state weld. It is commonly used for plastics and metals, and especially for joining dissimilar materials. In ultrasonic welding, there are no connective bolts, nails, soldering materials, or adhesives necessary to bind the materials together. When used to join metals, the temperature stays well below the melting point of the involved materials, preventing any unwanted properties which may arise from high temperature exposure of the metal. History Practical application of ultrasonic welding for rigid plastics was completed in the 1960s. At this point only hard plastics could be welded. The patent for the ultrasonic method for welding rigid thermoplastic parts was awarded to Robert Soloff and Seymour Linsley in 1965. Soloff, the founder of Sonics & Materials Inc., was a lab manager at Branson Instr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Thickness Gauge
In the field of industrial ultrasonic testing, ultrasonic thickness measurement (UTM) is a method of performing non-destructive measurement (gauging) of the local thickness of a solid element (typically made of metal, if using ultrasound testing for industrial purposes) based on the time taken by the ultrasound wave to return to the surface. This type of measurement is typically performed with an ultrasonic thickness gauge. Ultrasonic waves have been observed to travel through metals at a constant speed characteristic to a given alloy with minor variations due to other factors like temperature. Thus, given this information, called celerity, one can calculate the length of the path traversed by the wave using this formula: l_m = c t / 2 where l_m is the thickness of the sample c is the velocity of sound in the given sample t is the traverse time The formula features division by two because usually the instrumentation emits and records the ultrasound wave on the same side of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Testing
Ultrasonic testing (UT) is a family of non-destructive testing techniques based on the propagation of ultrasonic waves in the object or material tested. In most common UT applications, very short ultrasonic pulse-waves with center frequencies ranging from 0.1-15 MHz, and occasionally up to 50 MHz, are transmitted into materials to detect internal flaws or to characterize materials. A common example is ultrasonic thickness measurement, which tests the thickness of the test object, for example, to monitor pipework corrosion. Ultrasonic testing is often performed on steel and other metals and alloys, though it can also be used on concrete, wood and composites, albeit with less resolution. It is used in many industries including steel and aluminium construction, metallurgy, manufacturing, aerospace, automotive and other transportation sectors. History The first efforts to use ultrasonic testing to detect flaws in solid material occurred in the 1930s.''Nondestructive F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Soldering
Ultrasonic soldering (U/S soldering) is a flux-less soldering process that uses ultrasonic energy, without the need for chemicals to solder materials, such as glass, ceramics, and composites, hard to solder metals and other sensitive components which cannot be soldered using conventional means. Ultrasonic soldering is finding growing application in soldering of metals and ceramics from solar photovoltaics and medical shape memory alloys to specialized electronic and sensor packages. It has been used since 1955 to solder aluminum and other metals without the use of flux. Process Ultrasonic soldering is a distinctly different process than ultrasonic welding. Ultrasonic welding uses ultrasonic energy to join parts without adding any kind of filler material while ultrasonic soldering uses external heating to melt filler metal materials, namely solders, to form a joint. Ultrasonic soldering can be done with either a specialized soldering iron or a specialized solder pot. In eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Sensor
Ultrasonic transducers and ultrasonic sensors are devices that generate or sense ultrasound energy. They can be divided into three broad categories: transmitters, receivers and transceivers. Transmitters convert electrical signals into ultrasound, receivers convert ultrasound into electrical signals, and transceivers can both transmit and receive ultrasound. Applications and performance Ultrasound can be used for measuring wind speed and direction (anemometer), tank or channel fluid level, and speed through air or water. For measuring speed or direction, a device uses multiple detectors and calculates the speed from the relative distances to particulates in the air or water. To measure tank or channel liquid level, and also sea level (tide gauge), the sensor measures the distance (ranging) to the surface of the fluid. Further applications include: humidifiers, sonar, medical ultrasonography, burglar alarms, non-destructive testing and wireless charging. Systems typically use a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Motor
An ultrasonic motor is a type of piezoelectric motor powered by the ultrasonic vibration of a component, the stator, placed against another component, the rotor or slider depending on the scheme of operation (rotation or linear translation). Ultrasonic motors differ from other piezoelectric motors in several ways, though both typically use some form of piezoelectric material, most often lead zirconate titanate and occasionally lithium niobate or other single-crystal materials. The most obvious difference is the use of resonance to amplify the vibration of the stator in contact with the rotor in ultrasonic motors. Ultrasonic motors also offer arbitrarily large rotation or sliding distances, while piezoelectric actuators are limited by the static strain that may be induced in the piezoelectric element. One common application of ultrasonic motors is in camera lenses where they are used to move lens elements as part of the auto-focus system. Ultrasonic motors replace the noisier and ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Horn
An ultrasonic horn (also known as acoustic horn, sonotrode, acoustic waveguide, ultrasonic probe) is a tapering metal bar commonly used for augmenting the oscillation displacement amplitude provided by an ultrasonic transducer operating at the low end of the ultrasonic frequency spectrum (commonly between 15 and 100 kHz). The device is necessary because the amplitudes provided by the transducers themselves are insufficient for most practical applications of power ultrasound.Peshkovsky, S.L. and Peshkovsky, A.S., "Shock-wave model of acoustic cavitation", Ultrason. Sonochem., 2008. 15: p. 618–628. Another function of the ultrasonic horn is to efficiently transfer the acoustic energy from the ultrasonic transducer into the treated media,Peshkovsky, S.L. and Peshkovsky, A.S., "Matching a transducer to water at cavitation: Acoustic horn design principles", Ultrason. Sonochem., 2007. 14: p. 314–322. which may be solid (for example, in ultrasonic welding, ultrasonic cutting or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Hearing
Ultrasonic hearing is a recognised auditory effect which allows humans to perceive sounds of a much higher frequency than would ordinarily be audible using the inner ear, usually by stimulation of the base of the cochlea through bone conduction. Normal human hearing is recognised as having an upper bound of 15–28 kHz, depending on the person. Ultrasonic sinusoids as high as 120 kHz have been reported as successfully perceived. Two competing theories are proposed to explain this effect. The first asserts that ultrasonic sounds excite the inner hair cells of the cochlea basal turn, which are responsive to high frequency sounds. The second proposes that ultrasonic signals resonate the brain and are modulated down to frequencies that the cochlea can then detect. Researchers Tsutomu Oohashi et al. have coined the term hypersonic effect to describe the results of their controversial study supporting audibility of ultrasonics.T. Oohashi, E. Nishina, M. Honda, Y. Yonekura, Y. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasonic Grating
An ultrasonic grating is a type of diffraction grating produced by interfering ultrasonic waves in a medium altering the physical properties of the medium, and hence the refractive index, in a grid-like pattern. The term acoustic grating is a more general term that includes operation at audible frequencies. An ultrasonic wave is a sound wave at a frequency greater than 20 kHz. The human ear cannot recognize ultrasonic waves, but animals such as bats and dogs can. Ultrasonic waves can be produced by the piezoelectric effect and magnetostriction. Mechanism When ultrasonic waves are generated in a liquid in a rectangular vessel, the wave can be reflected from the walls of the vessel. These reflected waves are called echoes. The direct and reflected waves are superimposed, forming a standing wave. The density of the liquid at a node is more than the density at an antinode. Hence, the liquid acts as a diffraction grating to a parallel beam of light passed through the liquid at r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrasound Energy
Ultrasound energy, simply known as ultrasound, is a type of mechanical energy called sound characterized by vibrating or moving particles within a medium. Ultrasound is distinguished by vibrations with a frequency greater than 20,000 Hz, compared to audible sounds that humans typically hear with frequencies between 20 and 20,000 Hz. Ultrasound energy requires matter or a medium with particles to vibrate to conduct or propagate its energy. The energy generally travels through most mediums in the form of a wave in which particles are deformed or displaced by the energy then reestablished after the energy passes. Types of waves include shear, surface, and longitudinal waves with the latter being one of the most common used in biological applications. The characteristics of the traveling ultrasound energy greatly depend on the medium that it is traveling through. While ultrasound waves propagate through a medium, the amplitude of the wave is continually reduced or weakened wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
