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Rainfall Simulator
A rainfall simulator is used in soil science and hydrology to study how soil reacts to rainfall. Natural rainfall is difficult to use in experimentation because its timing and intensity cannot be reliably reproduced. Using simulated rainfall significantly speeds the study of erosion, surface runoff and Leaching (agriculture), leaching. The simplest rainfall simulators qualitatively demonstrate what happens to soil during rainfall events. They are useful for explaining how fertilizer may run off (wash away) rather than supply plant nutrition, nutrients to crops. History The evolution of the rainfall simulator started in the late 1800s when German Scientist Ewald Wollny formally studied erosion. As the study continued into the early 1910s, experimental field plots were designed to capture runoff from natural rainfall. In the 1930s, pioneers of erosion studies tightened control of their experiments by building the first rainfall simulators, ordinary sprinkle cans or pipes with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
20150630-OSEC-LSC-0225 (18688087724) (2)
Fifteen or 15 may refer to: *15 (number), the natural number following 14 and preceding 16 *one of the years 15 BC, AD 15, 1915, 2015 Music *Fifteen (band), a punk rock band Albums * 15 (Buckcherry album), ''15'' (Buckcherry album), 2005 * 15 (Ani Lorak album), ''15'' (Ani Lorak album), 2007 * 15 (Phatfish album), ''15'' (Phatfish album), 2008 * 15 (mixtape), ''15'' (mixtape), a 2018 mixtape by Bhad Bhabie * Fifteen (Green River Ordinance album), ''Fifteen'' (Green River Ordinance album), 2016 * Fifteen (The Wailin' Jennys album), ''Fifteen'' (The Wailin' Jennys album), 2017 * ''Fifteen'', a 2012 album by Colin James Songs *Fifteen (song), "Fifteen" (song), a 2008 song by Taylor Swift *"Fifteen", a song by Harry Belafonte from the album ''Love Is a Gentle Thing'' *"15", a song by Rilo Kiley from the album ''Under the Blacklight'' *"15", a song by Marilyn Manson from the album ''The High End of Low'' *"The 15th", a 1979 song by Wire Other uses *Fifteen, Ohio, a community in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tillage
Tillage is the agricultural preparation of soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shoveling, picking, mattock work, hoeing, and raking. Examples of draft-animal-powered or mechanized work include ploughing (overturning with moldboards or chiseling with chisel shanks), rototilling, rolling with cultipackers or other rollers, harrowing, and cultivating with cultivator shanks (teeth). Tillage that is deeper and more thorough is classified as primary, and tillage that is shallower and sometimes more selective of location is secondary. Primary tillage such as ploughing tends to produce a rough surface finish, whereas secondary tillage tends to produce a smoother surface finish, such as that required to make a good seedbed for many crops. Harrowing and rototilling often combine primary and secondary tillage into one operation. "Tillage" can also mean the lan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solenoid Valve
A solenoid valve is an electromechanically operated valve. Solenoid valves differ in the characteristics of the electric current they use, the strength of the magnetic field they generate, the mechanism they use to regulate the fluid, and the type and characteristics of fluid they control. The mechanism varies from linear action, plunger-type actuators to pivoted-armature actuators and rocker actuators. The valve can use a two-port design to regulate a flow or use a three or more port design to switch flows between ports. Multiple solenoid valves can be placed together on a manifold. Solenoid valves are the most frequently used control elements in fluidics. Their tasks are to shut off, release, dose, distribute or mix fluids. They are found in many application areas. Solenoids offer fast and safe switching, high-reliability, long service life, good medium compatibility of the materials used, low control power and compact design. Operation There are many valve design variation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thunderstorm
A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are sometimes called thundershowers. Thunderstorms occur in a type of cloud known as a cumulonimbus. They are usually accompanied by strong winds and often produce heavy rain and sometimes snow, sleet, or hail, but some thunderstorms produce little precipitation or no precipitation at all. Thunderstorms may line up in a series or become a rainband, known as a squall line. Strong or severe thunderstorms include some of the most dangerous weather phenomena, including large hail, strong winds, and tornadoes. Some of the most persistent severe thunderstorms, known as supercells, rotate as do cyclones. While most thunderstorms move with the mean wind flow through the layer of the troposphere that they occupy, vertical wind shear sometimes causes a de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center Pivot Irrigation
Center-pivot irrigation (sometimes called central pivot irrigation), also called water-wheel and circle irrigation, is a method of crop irrigation in which equipment rotates around a pivot and crops are watered with sprinklers. A circular area centered on the pivot is irrigated, often creating a circular pattern in crops when viewed from above (sometimes referred to as ''crop circles'', not to be confused with those formed by circular flattening of a section of a crop in a field). Most center pivots were initially water-powered, however today most are propelled by electric motors. Center-pivot irrigation systems are beneficial due to their ability to efficiently use water and optimize a farm's yield. The systems are highly effective on large land fields. History Center-pivot irrigation was invented in 1940 by the farmer Frank Zybach, who lived in Strasburg, Colorado. It is recognized as an effective method to improve water distribution to fields. In 1952, Zybach went into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distribution Uniformity
Distribution uniformity or DU in irrigation is a measure of how uniformly water is applied to the area being watered, normally expressed as percentage, and not to be confused with efficiency. The distribution uniformity is often calculated when performing an irrigation audit. The DU should not be confused with the coefficient of uniformity (CU) which is often preferred for describing the performance of overhead pressurized systems. The most common measure of DU is the low quarter DU expressed as DUlq, which is a measure of the average of the lowest quarter of samples, divided by the average of all samples expressed as percentage. The higher the DUlq, the more uniform the coverage of the area measured. If all samples are equal, the DUlq is 1.0 or 100%. There is no universal value of DUlq for satisfactory system performance. A value of >.80 or 80% is considered above average. Distribution uniformity may be helpful as a starting point for irrigation scheduling Irrigation schedul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spray Nozzle
A spray nozzle is a device that facilitates the dispersion of a liquid by the formation of a spray. The production of a spray requires the fragmentation of liquid structures, such as liquid sheets or ligaments, into droplets, often by using kinetic energy to overcome the cost of creating additional surface area. A wide variety of spray nozzles exist, that make use of one or multiple liquid breakup mechanisms, which can be divided into three categories: liquid sheet breakup, jets and capillary waves. Spray nozzles are of great importance for many applications, where the spray nozzle is designed to have the right spray characteristics. Spray nozzles can have one or more outlets; a multiple outlet nozzle is known as a compound nozzle. Multiple outlets on nozzles are present on spray balls, which have been used in the brewing industry for many years for cleaning casks and kegs. Spray nozzles range from heavy duty industrial uses to light duty spray cans or spray bottles. Singl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and even by industry. Further, both spellings are often used ''within'' a particular industry or country. Industries in British English-speaking countries typically use the "gauge" spelling. is the pressure relative to the ambient pressure. Various units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the SI unit of pressure, the pascal (Pa), for example, is one newton per square metre (N/m2); similarly, the pound-force per square inch (psi) is the traditional unit of pressure in the imperial and U.S. customary systems. Pressure may also be expressed in terms of standard atmospheric pressure; the atmosphere (atm) is equal to this pressure, and the torr is defined as of this. Manometric u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syringe
A syringe is a simple reciprocating pump consisting of a plunger (though in modern syringes, it is actually a piston) that fits tightly within a cylindrical tube called a barrel. The plunger can be linearly pulled and pushed along the inside of the tube, allowing the syringe to take in and expel liquid or gas through a discharge orifice at the front (open) end of the tube. The open end of the syringe may be fitted with a hypodermic needle, a nozzle or tubing to direct the flow into and out of the barrel. Syringes are frequently used in clinical medicine to administer injections, infuse intravenous therapy into the bloodstream, apply compounds such as glue or lubricant, and draw/measure liquids. There are also prefilled syringes (disposable syringes marketed with liquid inside). The word "syringe" is derived from the Greek σύριγξ ('' syrinx'', meaning "Pan flute", "tube"). Medical syringes Sectors in the syringe and needle market include disposable and safe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rain
Rain is water droplets that have condensed from atmospheric water vapor and then fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water for hydroelectric power plants, crop irrigation, and suitable conditions for many types of ecosystems. The major cause of rain production is moisture moving along three-dimensional zones of temperature and moisture contrasts known as weather fronts. If enough moisture and upward motion is present, precipitation falls from convective clouds (those with strong upward vertical motion) such as cumulonimbus (thunder clouds) which can organize into narrow rainbands. In mountainous areas, heavy precipitation is possible where upslope flow is maximized within windward sides of the terrain at elevation which forces moist air to condense and fall out as rainfall along the sides of mountains. On the leeward side of mountains, desert climates can exi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canopy (biology)
In biology, the canopy is the aboveground portion of a plant cropping or crop, formed by the collection of individual plant crowns. In forest ecology, canopy also refers to the upper layer or habitat zone, formed by mature tree crowns and including other biological organisms ( epiphytes, lianas, arboreal animals, etc.). The communities that inhabit the canopy layer are thought to be involved in maintaining forest diversity, resilience, and functioning. Sometimes the term canopy is used to refer to the extent of the outer layer of leaves of an individual tree or group of trees. Shade trees normally have a dense canopy that blocks light from lower growing plants. Observation Early observations of canopies were made from the ground using binoculars or by examining fallen material. Researchers would sometimes erroneously rely on extrapolation by using more reachable samples taken from the understory. In some cases, they would use unconventional methods such as chairs susp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
