Heh, confused.
Noise is mainly used to pollute the environment ^_^!
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Introduction to ultrasound waves
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We know that when an object vibrates it makes a sound. Scientists refer to the number of vibrations per second as the frequency of sound, which is measured in hertz. The frequency of sound waves that we human ears can hear is 20 to 20,000 hertz. We cannot hear sound waves when they vibrate at frequencies greater than 20,000 Hz or less than 20 Hz. Therefore, we call sound waves with a frequency higher than 20,000 Hz "ultrasound". Usually used for medical diagnosis of ultrasound frequency of 1 to 5 megahertz. Ultrasonic waves have good directionality, strong penetrating ability, easy to obtain a more concentrated sound energy, in the water propagation distance and other characteristics. It can be used for distance measurement, speed measurement, cleaning, welding, stone crushing and so on. In medicine, military, industry, agriculture has obvious role.
Theoretical studies have shown that, under the same conditions of amplitude, the energy of an object vibration is proportional to the frequency of vibration, ultrasonic propagation in the medium, the medium point of vibration of the frequency is very high, and therefore a lot of energy. In the dry winter in the north of China, if the ultrasonic waves into the water tank, the intense vibration will make the tank of water broken into many small droplets, and then a small fan to the droplets blown into the room, you can increase the indoor air humidity. This is the principle of ultrasonic humidifier. Laryngitis. For diseases such as laryngitis and bronchitis, it is difficult for medicines to reach the affected area by blood flow. Using the principle of humidifier, the medicine atomized, so that the patient inhaled, can improve the efficacy of treatment. The use of ultrasound energy can also make the body of the stones do violent forced vibration and broken, thus slowing down the pain, to achieve the purpose of healing.
The generation of ultrasonic waves
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Sound waves are the state of mechanical vibration of an object (or energy) in the form of propagation. By vibration is meant the back-and-forth motion of a mass of matter near its equilibrium position. For example, after the drum surface is struck, it vibrates up and down, and this state of vibration spreads in all directions through the air medium, which is sound waves. Ultrasound refers to vibration frequencies greater than 20KHz or more, the number of vibrations per second (frequency) is very high, beyond the upper limit of the human ear hearing (20,000Hz), people will be unable to hear the sound waves called ultrasound. Ultrasound and audible sound is essentially the same, their **** the same point is a mechanical vibration, usually in the form of longitudinal waves in the elastic medium will be propagated, is a form of energy propagation, the difference is that the ultrasound frequency is high, the wavelength is short, within a certain distance along the straight line propagation has a good beam and directionality, the current ultrasound abdominal imaging used in the frequency range between the 2 ∽ 5MHz, commonly used for 3 ∽ 3.5MHz (3 ∽ 3.5MHz per second). 3.5MHz (1 vibration per second for 1Hz, 1MHz = 10^6Hz, that is, 1 million vibrations per second, the frequency of audible waves in the 16-20,000HZ between).
The two main parameters of ultrasound
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The two main parameters of ultrasound: Frequency: F ≥ 20KHz; Power Density: p = Transmit Power (W) / Transmit Area (cm2); Usually p ≥ 0.3w/cm2; ultrasonic propagation of liquid can be on the surface of the object to clean the dirt, and the principle of the available "Cavitation" phenomenon to explain: ultrasonic vibration in the liquid propagation of sound wave pressure to reach an atmospheric pressure, its power density of 0.35w/cm2, then the ultrasonic sound wave pressure peak can reach a vacuum or negative pressure, but in fact there is no negative pressure exists, so in the liquid to produce a very large pressure, the liquid molecules will be cracked Into a cavity a cavitation nucleus. This cavity is very close to the vacuum, it is in the ultrasonic pressure reversal to reach the maximum rupture, due to the rupture and the resulting strong impact will be the surface of the object dirt impact down. This by the countless tiny cavitation bubble rupture and produce shock wave phenomenon called "cavitation" phenomenon.
The role of ultrasonic waves
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Glass parts. Glass and ceramic products descaling is a trouble, if these items into the cleaning fluid, and then pass into the ultrasonic waves, cleaning fluid of the violent vibration of the impact of the items on the dirt, can be quickly cleaned.
Although humans can not hear ultrasound, but many animals have this ability. They can use ultrasound to "navigate", hunt for food, or avoid hazards. You may have seen many bats flying back and forth in the courtyard at night in the summer, why do they fly in the absence of light and not lose their way? The reason is that bats can emit ultrasonic waves of 2 to 100,000 Hz, which is like an active "radar station". Bats use this "radar" to determine whether an insect or an obstacle is in front of them. The mass of the radar can be tens, hundreds, or thousands of kilograms, and in some important performance accuracy. Bats are far superior to modern radiolocators in terms of accuracy, immunity to interference, and so on. In-depth study of the function and structure of various organs in animals, the knowledge gained to improve existing equipment, which is a new discipline developed in recent decades, called bionics.
We humans did not learn to use ultrasound until the First World War, which is the use of the principle of "sonar" to detect targets in the water and their status, such as the location of submarines. At this time, people send a series of different frequencies of ultrasound to the water, and then record and process the reflected echo, from the echo characteristics we can estimate the probe distance, shape and dynamic changes. The earliest use of ultrasound in medicine is in 1942, the Austrian doctor Dusik for the first time with ultrasound technology to scan the structure of the brain; later to the 60's doctors began to apply ultrasound to the detection of abdominal organs. Today, ultrasound scanning technology has become an indispensable tool for modern medical diagnosis.
The working principle of medical ultrasound is similar to that of sonar, in that ultrasound is emitted into the body, and when it encounters an interface in the body, it is reflected and refracted, and may be absorbed and attenuated in human tissue. Because the shape and structure of various human tissues are not the same, so its reflection and refraction and absorption of ultrasound waves to different degrees, doctors are reflected by the instrument through the waveform, curve, or image characteristics to identify them. In addition, combined with anatomical knowledge, normal and pathological changes, can diagnose whether the organs examined are diseased.
Currently, there are different forms of ultrasound diagnostic methods used by physicians, which can be divided into four main categories: A-type, B-type, M-type, and D-type.
Type A: This is a method of displaying tissue characteristics by waveforms, and is mainly used to measure the diameter of an organ to determine its size. It can be used to identify physical characteristics of the tissue, such as the presence of substance, fluid or gas.
Type B: A flat graphic representation of the tissue being examined. During the examination, the reflected signals from the body interface are first transformed into points of light of varying intensity, which can be visualized on a fluorescent screen. This method is intuitive, reproducible, and can be used for before and after comparisons, so it is widely used in the diagnosis of obstetrics and gynecology, urology, digestion, and cardiovascular system diseases.
M: It is a method used to observe the temporal changes of the active interface. It is most suitable for checking the activity of the heart, and the dynamic change of its curve is called echocardiography, which can be used to observe the position of the heart's various layers of structures, the state of activity, the condition of the structure, etc. It is mostly used to assist in the diagnosis of cardiac and macrovascular epidemics.
Type D: It is an ultrasound diagnostic method specifically designed to detect blood flow and organ activity, also known as Doppler ultrasound diagnostic method. It can determine whether the blood vessels are open, whether the lumen is narrowed, occluded and the location of the lesion. The new generation of D-mode ultrasound can also quantify the flow of blood in the lumen. In recent years, scientists have developed a color-coded Doppler system, which can show the direction of blood flow in different colors under the indication of the anatomical landmarks of the echocardiogram, and the shade of the color represents the flow rate of the blood. Now there are also three-dimensional ultrasound visualization, ultrasound CT, ultrasound endoscopy and other ultrasound technology continues to emerge, and can also be used in conjunction with other examination instruments, so that the diagnostic accuracy of the disease is greatly improved. Ultrasound technology is playing a huge role in the medical community, with the progress of science, it will be more perfect, will be better for the benefit of mankind.
The study of ultrasound generation, propagation, reception, as well as a variety of ultrasound effects and applications of the acoustic branch called ultrasonics. Generate ultrasonic devices have mechanical ultrasonic generator (such as gas whistle, whistle and liquid whistle, etc.), the use of electromagnetic induction and electromagnetic effect of the principle of electric ultrasonic generator,
and the use of piezoelectric crystal electrostriction effect and ferromagnetic material made of magnetostriction effect of electroacoustic transducer.
Ultrasonic effect When ultrasonic waves propagate in the medium, due to the interaction of ultrasound and the medium, the medium undergoes physical and chemical changes, resulting in
a series of mechanical, thermal, electromagnetic and chemical ultrasonic effects, including the following four kinds of effects:
1 Mechanical effect. The mechanical effect of ultrasound can contribute to the emulsification of liquids, liquefaction of gels and dispersion of solids. When the ultrasonic fluid medium to form a standing wave, suspended in the fluid of tiny particles due to mechanical forces and cohesion in the wave joints, the formation of periodic accumulation in space. When ultrasonic waves propagate in piezoelectric and magnetostrictive materials, they are induced by the mechanical action of the ultrasonic waves due to the induced electrode polarization and induced magnetization (see dielectric physics and magnetostriction).
②Cavitation. Ultrasound can produce a large number of small bubbles when acting on the liquid . One reason is that the local tensile stress in the liquid and the formation of negative pressure, the reduction in pressure so that the original dissolved in the liquid gas supersaturation, and escape from the liquid, becoming a small bubble. Another reason is the strong tensile stress to the liquid "torn" into a cavity, known as cavitation. Inside the cavity is liquid vapor or dissolved in the liquid of another gas, or even a vacuum. Due to the cavitation effect of the formation of small bubbles with the vibration of the surrounding medium and constantly moving, growing or suddenly burst. When the bursting of the surrounding liquid suddenly rushed into the bubble and produce high temperature, high pressure, at the same time produce shock waves. With cavitation accompanied by internal friction can form a charge, and in the bubble due to discharge and produce luminescence. Ultrasonic treatment in the liquid in most of the technology related to cavitation.
3 thermal effect. Due to the high frequency of ultrasound, large energy, absorbed by the medium can produce significant thermal effects.
④Chemical effect. The role of ultrasound can promote the occurrence or accelerate some chemical reactions. For example, pure distilled water after ultrasonic treatment to produce hydrogen peroxide; dissolved nitrogen water after ultrasonic treatment to produce nitrous acid; dyes in aqueous solution after ultrasonic treatment will change color or fade. The occurrence of these phenomena is always accompanied by cavitation. Ultrasound can also accelerate the hydrolysis, decomposition and polymerization of many chemical substances. Ultrasound also has a significant effect on photochemical and electrochemical processes. A variety of amino acids and other organic substances in aqueous solution after ultrasound treatment, the characteristic absorption spectral band disappears and a uniform general absorption, which indicates that the cavitation effect of the molecular structure has changed .
Ultrasonic applications Ultrasonic effects have been widely used in practice, mainly in the following areas:
①Ultrasonic testing. Ultrasonic wavelength is shorter than the general sound waves, has a better directionality, and can pass through the opaque material, this characteristic has been widely used in ultrasonic flaw detection, thickness measurement, distance measurement, remote control and ultrasound imaging technology. Ultrasonic imaging is the use of ultrasound to present the internal image of opaque material technology. The ultrasonic waves from the transducer through the acoustic lens focused on the opaque specimen, the ultrasonic waves transmitted from the specimen carries the information of the illuminated part (e.g., the ability of reflection, absorption and scattering of acoustic waves), through the acoustic lens convergence in the piezoelectric receiver, the resulting electrical signals into the amplifier, the use of scanning systems can be the opaque specimens the image of the fluorescent screen. The above device is called an ultrasound microscope. Ultrasound imaging technology has been widely used in medical examination, in the microelectronic device manufacturing industry is used to check the large-scale integrated circuits, in materials science is used to show the different components of the alloy in the region and grain boundaries and so on. Acoustic holography is an acoustic imaging technique that utilizes the interference principle of ultrasound to record and reproduce three-dimensional images of opaque objects, the principle of which is basically the same as that of holography of light waves, except that the means of recording are different (see holography). The same ultrasonic signal source is used to excite two transducers placed in a liquid, which emit two coherent beams of ultrasound: one beam passes through the object under study and becomes the object wave, and the other beam serves as the reference wave. The object wave and the reference wave are coherently superimposed on the liquid surface to form an acoustic hologram, which is illuminated by a laser beam to obtain a reproduced image of the object by utilizing the diffraction effect produced by the laser light when it is reflected on the acoustic hologram, and is usually observed in real time with a video camera and a television set.
②Ultrasonic processing. The use of ultrasound mechanical effect, cavitation, thermal and chemical effects, can be ultrasonic welding, drilling, crushing of solids, emulsification, degassing, dust removal, pot scale, cleaning, sterilization, chemical reactions and biological research, etc., in the industrial and mining industry, agriculture, medical and other sectors to obtain a wide range of applications.
3 basic research. Ultrasonic action in the medium, in the medium to produce acoustic relaxation process, acoustic relaxation process is accompanied by energy in the molecules of the respective electrical degree of transport between the process, and in the macroscopic manifestation of the absorption of acoustic waves (see acoustic waves). The properties and structure of matter can be explored through the law of absorption of ultrasound by matter, and research in this area constitutes the acoustic branch of molecular acoustics. The wavelength of ordinary sound waves is much larger than the atomic spacing in solids, which can be treated as a continuous medium under these conditions. But for the frequency of 1012 Hz above the special ultrasonic waves, the wavelength can be compared with the atomic spacing in the solid, this time the solid must be treated as having a spatial periodicity of the dot matrix structure. The energy of the dot matrix vibrations is quantized and is called a phonon (see physics of solids). The action of ultrasound on solids can be reduced to the interaction of ultrasound with thermal phonons, electrons, photons, and various quasiparticles. The study of the laws of generation, detection, and propagation of ultrasound in solids, as well as the study of acoustic phenomena in the quantum liquid, liquid helium, constitutes a new field of modern acoustics -
Sound waves are one of the classes of sound that belongs to the category of mechanical waves, and acoustic waves are refers to a longitudinal wave that can be perceived by the human ear, with a frequency range of 16Hz-20KHz. when the frequency of a sound wave is lower than 16Hz it is called an infrasound wave, and higher than 20KHz it is called an ultrasonic sound wave.
Ultrasonic waves have the following characteristics:
1) Ultrasonic waves can be effectively propagated in gases, liquids, solids, solid melts and other media.
2) ultrasound can transmit very strong energy.
3) ultrasound will produce reflection, interference, superposition and *** vibration phenomenon.
4) ultrasound propagation in liquid media, can produce strong impact and cavitation phenomenon at the interface.
Ultrasonic waves are a member of the large family of sound waves.
Sound waves are a form of propagation of the state of mechanical vibration (or energy) of an object. Vibration is the back-and-forth motion of a mass of matter near its equilibrium position. For example, when a drum is struck, it vibrates up and down, and this state of vibration propagates in all directions through the air medium, which is a sound wave.
Ultrasonic waves are sound waves whose vibration frequency is greater than 20 kHz, and which cannot be heard or felt in the natural environment.
The concept of ultrasound therapy:
Ultrasonic therapy is an important part of ultrasound medicine. Ultrasound therapy when the ultrasound energy will be applied to the diseased parts of the human body, in order to achieve the purpose of treating the disease and promoting the recovery of the organism.
In the world, ultrasound is widely used in diagnostics, therapeutics, engineering, biology and other fields. Safari home ultrasound therapy machine belongs to the use of ultrasound therapeutics.
(A) engineering applications: underwater positioning and communications, underground resource exploration, etc.
(B) biological applications: shear macromolecules, bioengineering and treatment of seeds, etc.
(C) diagnostic applications: A-type, B-type, M-type, D-type, dual-performance and color ultrasound, etc.
(D) therapeutic applications: physical therapy, cancer treatment, surgery, body lithotripsy, ultrasound, ultrasound and other therapeutic applications.
The characteristics of ultrasonic waves
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1, ultrasonic waves in the propagation of the strong direction, energy is easy to focus.
2, ultrasonic waves can be propagated in a variety of different media, and can be propagated far enough distance.
3, the interaction between ultrasound and sound transmission medium is moderate, easy to carry information about the state of the sound transmission medium (diagnosis or effect on the sound transmission medium. (Treatment)
Ultrasonic wave is a form of fluctuation, it can be used as a carrier or medium for detecting and loading information (such as B ultrasound used as a diagnostic); ultrasound at the same time is a form of energy, when its intensity exceeds a certain value, it can be through the interaction of the medium with the propagation of ultrasonic waves to affect, change or destroy the latter's state, nature and structure (used as a therapeutic).
History of the development of ultrasound waves
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I. International:
Since the end of the 19th century to the beginning of the 20th century, the discovery of the piezoelectric effect and the anti-piezoelectric effect in physics, after the discovery of the piezoelectric effect, people solved the use of electronics to produce ultrasonic methods, and from then on quickly opened the development and promotion of ultrasound technology of the history of the chapter.
In 1922, Germany appeared the first ultrasound therapy invention patent.
In 1939, the literature published on the clinical effects of ultrasound treatment.
The late 40's ultrasound therapy in Europe and the United States, until the first international medical ultrasound conference held in 1949, there is ultrasound therapy paper exchanges for the development of ultrasound therapy laid the foundation for the second international ultrasound conference in 1956, there have been a number of papers published, ultrasound therapy has entered the practical stage of maturity.
Second, the domestic side:
Domestic in the field of ultrasound therapy started a little late in the early 1950s, only a few hospitals to carry out ultrasound therapy, from 1950, first began to treat a variety of diseases in Beijing with 800KHz ultrasound therapy machine, to the 50s began to gradually promote, and have a domestic instrument. Public literature reports were first published in 1957. By the 1970s, there were various types of domestic ultrasound therapeutic instrument, ultrasound therapy popularized in large hospitals across the country.
Over the past 40 years, the country's major hospitals have accumulated a considerable amount of information and relatively rich clinical experience. In particular, the emergence of ultrasound extracorporeal mechanical wave lithotripsy and ultrasound surgery in the early 1980s was a major breakthrough in the history of stone disease treatment. Nowadays, it has been popularized and applied internationally. High-intensity focused ultrasound noninvasive surgery has made ultrasound therapy occupy an important position in contemporary medical technology. And in the 21st century (HIFU) ultrasound focused surgery has been hailed as the latest technology for the treatment of tumors in the 21st century.
Mechanism of ultrasound treatment:
1. Mechanical effect: the effect of ultrasound in the medium forward. (Ultrasound propagation in the medium is produced by reflection and mechanical effects) it can cause a number of body reactions. Ultrasound vibration can be caused by the movement of substances within the tissue cells, due to the ultrasound micro-massage, so that the cell plasma flow, cell shock, rotation, friction, thus producing the role of cell massage, also known as the "internal massage" This is the unique characteristics of ultrasound therapy can change the permeability of the cell membrane, stimulate the diffusion of cellular semi-permeable membrane process, promote the metabolism, accelerate blood and lymphatic flow, and promote the development of the body. Metabolism, accelerate blood and lymph circulation, improve cell ischemia and hypoxia, improve tissue nutrition, change the rate of protein synthesis, improve regenerative function. Make changes in the internal structure of the cell, resulting in functional changes in the cell, so that the hard connective tissue extension, flaccid.
The mechanical action of ultrasound can soften tissues, enhance penetration, improve metabolism, promote blood circulation, stimulate the nervous system and cellular functions, thus having the unique therapeutic significance of ultrasound.
2. Thermal effect: the human body tissue has a relatively large absorption capacity of ultrasound energy, so when the ultrasound in the human body tissue propagation process, its energy is constantly absorbed by the tissue into the heat, the result is that the organization's own temperature rise.
Heat generation process is both mechanical energy in the medium into thermal energy conversion process. That is, endogenous heat. Ultrasound warming effect can increase blood circulation, accelerate metabolism, improve local tissue nutrition, enhance enzyme activity. In general, the thermal effect of ultrasound to bone and connective tissue is significant, fat and blood for the least.
3. Physical and chemical effects: the mechanical and thermal effects of ultrasound can promote a number of physical and chemical changes. It has been proved that some physical and chemical effects are often the secondary effects of the above effects. TS-C-type therapy machine through the physical and chemical effects of the following five secondary effects:
A. Dispersive effect: ultrasound can improve the permeability of biological membranes, ultrasound, the cell membrane of potassium, calcium ions after the effect of strong changes in permeability. Thus, it enhances the diffusion process of the biofilm, promotes the exchange of substances, accelerates the metabolism, and improves the nutrition of the tissues.
B. Thixotropic effect: Under the action of ultrasound, the gel can be transformed into a sol-gel state. The softening effect on muscle, tendon, and some pathological changes related to tissue dehydration. Such as rheumatoid arthritis lesions and the treatment of degenerative lesions of joints, tendons and ligaments.
C. Cavitation: cavitation is formed, either by unidirectional vibration that remains stable, or secondary to swelling to the point of collapse, with altered cellular function and increased intracellular calcium levels. Fibroblasts are activated, protein synthesis increases, vascular permeability increases, angiogenesis is accelerated, and collagen tension increases.
D. Polymerization and depolymerization: water molecule polymerization is the process of synthesizing multiple identical or similar molecules into one larger molecule. Macromolecular depolymerization is the process of turning a large chemical molecule into a smaller one. It can lead to increased hydrolase and proenzyme activity in the joints.
E. Anti-inflammatory, repair of cells and molecules: the ultrasound effect can make the tissue PH value to the alkaline side. Relieves local acidosis associated with inflammation. Ultrasound can affect blood flow, produce inflammation-causing effects, inhibit and play an anti-inflammatory role. Mobilizes leukocytes and promotes angiogenesis. Collagen synthesis and maturation. Promotes or inhibits the repair and healing process of damage. This results in the process of cleansing, activating and repairing damaged cells and tissues.
Quantum Acoustics.
Ultrasonic waves can also be radar detection. Cleaning the more delicate items, such as clocks, can use ultrasound to break the patient's body gallstones, but also the use of ultrasound distance measurement.
Ultrasonic detection is also used for resistance welding joint strength detection.
The human ear can hear the fluctuation, its frequency is about 16Hz to 20KHz between, if the "fluctuation" of the frequency is higher than this range, then human beings will not be able to hear, specially called ultrasound. The so-called "fluctuations" are the mechanical vibrations of particles in matter when they are subjected to external forces. For example, if you pull down on an object suspended under a spring so that the spring extends, and then release the object, the object is subjected to the force of the spring, resulting in an up and down reciprocating vibration, which deviates from its rest position in relation to time, that is, sinusoidal waveforms.
Ultrasonic waves can be divided into longitudinal wave, transverse wave, surface wave, Lamb wave four kinds of fluctuation according to its wave transmission direction. Its transmission in the material, according to the law of indestructibility of energy, sound waves in a material transmission, or from a material into another material, due to attenuation, reflection and refraction of the role of its energy is inevitably weaker and weaker; but in the part of the material density is greater, the sound pressure will increase (but because of the sound impedance is also greater, the energy is still reduced)，and vice versa, in the part of the loose, the volume of its volume is greater.
Related articles
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Night experiments
The Italian scientist Spalatje used to walk around the neighborhood after dinner. He often saw that many bats flew nimbly in the air, but never crashed into the walls. This phenomenon aroused his curiosity: what is the special ability of bats to fly freely in the night sky?
On a clear night in the summer of 1793, the bustling city gradually calmed down. After a hurried meal, Paslatje stepped out into the street and released the bats from their cages. When he saw the few bats released flying back and forth with lightness and agility, he could not help but scream. Because the bats, the eyes are all blinded by him, are "blind" ah.
Why did Sparatje blindfold the bats? It turns out that whenever he saw bats flying freely at night, he always thought that these little elves must have a pair of particularly sharp eyes, so it would be impossible for them to navigate through all kinds of obstacles in the darkness of the night and catch moths with agility. Yet the truth was completely unexpected. Sparatje wondered: without eyes, on what basis could a bat recognize objects in front of it and catch nimble moths?
So he blocked the bat's nose. As a result, the bat still flew through the air with such agility and ease. "Could it be that with his film-like wings, he is able not only to fly, but also to see everything at night?" Sparatje guessed so. He caught a few more bats and painted their entire bodies with paint, yet it still didn't affect their flight.
Finally, Sparajet plugged the bats' ears and put them into the night sky. This time, the bats were not as godlike as they had been earlier. They bumped around in the air like headless flies and soon fell to the ground.
Ah! Bats fly at night to catch food, and it turns out that they rely on their sense of hearing to recognize their direction and confirm their target!
Sparajet's experiment, which unveiled the secret of bat flight, prompted many people to think further: how can a bat's ears "penetrate" the night and "hear" objects that have no sound?
Later, people continued to study, and finally figured out the mystery. Originally, bats rely on their throats to send out inaudible "ultrasound", which spreads along a straight line, and when it touches an object, it reflects back like light shining on a mirror. When the bat receives this "ultrasound" with its ears, it can make a quick judgment and fly freely to catch food.
Nowadays, people use ultrasound to navigate for airplanes and ships, and to search for underground treasures. Like a silent meritocracy, ultrasound is widely used in industry, agriculture, medicine and the military. Sparatje could not have imagined that his experiments would bring such a great boon to mankind.
Ultrasonic welding--
Applying ultrasonic waves can be used on thermoplastic workpieces using a variety of methods such as fusion welding, riveting, forming or spot welding. Ultrasonic welding equipment can be operated independently or used in an automated production environment. Plastic workpieces with built-in precision electronic components, such as microswitches, are suitable for ultrasonic welding. At the same time, more than one method may be used to process the finished product, such as welding floppy disks and cassette tapes using riveting inside, while the outside of the weld using the fusion welding method
Ultrasonic air bubbles refining chemical principle
Liquid generated within the strong ultrasonic triggered by high-energy dense air bubble group, the air bubbles explode, the instantaneous generation of up to 1,000 atmospheric pressure and thousands of degrees of high temperature in a tiny space. pressure and thousands of degrees of high temperature.
In the high pressure and high temperature, heavy oil molecules in the C-C bond breaking, large molecules of hydrocarbons decomposed into small molecules of hydrocarbons; raw materials in the sulfur in the ultrasound and the role of the air bubbles, the C-S bond breakage, transformed into intermediate olefins, n-alkanes, aromatics and hydrogen sulfide. The generated olefins are transformed into n-alkanes and aromatics in the process of ultrasonic pyrolysis.
High-sulfur heavy oil macromolecules are converted into low-sulfur small molecules of gasoline and diesel. The small amount of residue that is not converted or is converted to a low degree is used to prepare high quality bitumen.