Search results
Results from the WOW.Com Content Network
Sonication is the act of applying sound energy to agitate particles in a sample, for various purposes such as the extraction of multiple compounds from plants, microalgae and seaweeds. [1] Ultrasonic frequencies (> 20 kHz) are usually used, leading to the process also being known as ultrasonication or ultra-sonication. [2]
Furthermore, ultrasonic acoustic emissions (UAE) have been detected in a range of different plants which result from collapsing water columns under high tension. [14] UAE studies show different frequencies of sound emissions based on whether or not drought conditions are present.
In a hydroponic system ultrasonic hydroponic foggers [1] are used to create a fine mist, the individual particle size of which is typically of about 5 μm in diameter. These fine particles are capable of carrying nutrients from the standing water of a reservoir to plant roots. Benefits include humidification and exponentially improved root ...
Electronic pest control is the name given to any of several types of electrically powered devices designed to repel or eliminate pests, usually rodents or insects. Since these devices are not regulated under the Federal Insecticide, Fungicide, and Rodenticide Act in the United States, the EPA does not require the same kind of efficacy testing that it does for chemical pesticides.
Biofouling or biological fouling is the accumulation of microorganisms, plants, algae, or small animals where it is not wanted on surfaces such as ship and submarine hulls, devices such as water inlets, pipework, grates, ponds, and rivers that cause degradation to the primary purpose of that item.
Ultrasound can also provide additional information such as the depth of flaws in a welded joint. Ultrasonic inspection has progressed from manual methods to computerized systems that automate much of the process. An ultrasonic test of a joint can identify the existence of flaws, measure their size, and identify their location.
This is most commonly the result of exposure to the sun at high altitude, and in areas where shorter wavelengths are readily reflected from bright surfaces, such as snow, water, and sand. UV generated by a welding arc can similarly cause damage to the cornea, known as "arc eye" or welding flash burn, a form of photokeratitis .
Ultrasonic algae control is a commercial technology that has been claimed to control the blooming of cyanobacteria, algae, and biofouling in lakes, and reservoirs, by using pulsed ultrasound. [ 6 ] [ 7 ] The duration of such treatment is supposed to take up to several months, depending on the water volume and algae species.