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Magnetic Stirrer
A magnetic stirrer or magnetic mixer is a laboratory device that employs a rotating magnetic field to cause a stir bar (or ''flea'') immersed in a liquid to spin very quickly, thus stirring it. The rotating field may be created either by a rotating magnet or a set of stationary electromagnets, placed beneath the vessel with the liquid. It is used in chemistry and biology as a convenient way to stir small volumes and where other forms of stirring, such as overhead stirrers and stirring rods, may not be viable. Design file:Magnetic Stir Bars.JPG, left, Four magnetic stir bars next to a metre stick A magnetic stirrer consists of a magnetic bar placed within the liquid which provides the stirring action. The stir bar's motion is driven by another rotating magnet or assembly of electromagnets in the stirrer device, beneath the vessel containing the liquid. Stir bars are typically coated in PTFE, or, less often, in glass; the coatings are intended to be chemically inert, not contam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vortex Mixer
A vortex mixer, or vortexer, is a simple device used commonly in laboratories to mix small vials of liquid. It consists of an electric motor with the drive shaft oriented vertically and attached to a cupped rubber piece mounted slightly off-center. As the motor runs the rubber piece oscillates rapidly in a circular motion. When a test tube or other appropriate container is pressed into the rubber cup (or touched to its edge) the motion is transmitted to the liquid inside and a vortex is created. Most vortex mixers are designed with 2 or 4-plate formats, have variable speed settings ranging from 100 to 3,200 rpm, and can be set to run continuously, or to run only when downward pressure is applied to the rubber piece. Use Vortex mixers are quite commonplace in biotechnology, bioscience laboratories. In cell culture and microbiology laboratories they may be used to suspension (chemistry), suspend cells. In a biochemistry, biochemical or analytical chemistry, analytical laborator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samarium–cobalt Magnet
A samarium–cobalt (SmCo) magnet, a type of rare-earth magnet, is a strong permanent magnet made of two basic elements: samarium and cobalt. They were developed in the early 1960s based on work done by Karl Strnat at Wright-Patterson Air Force Base and Alden Ray at the University of Dayton. In particular, Strnat and Ray developed the first formulation of SmCo5. Samarium–cobalt magnets are generally ranked similarly in strength to neodymium magnets, but have higher temperature ratings and higher coercivity. Attributes Some attributes of samarium-cobalts are: * Samarium-cobalt magnets are extremely resistant to demagnetization. * These magnets have good temperature stability (maximum use temperatures between and ; Curie temperature, Curie temperatures from to . * They are expensive and subject to price fluctuations (cobalt is market price sensitive). * Samarium–cobalt magnets have a strong resistance to corrosion and oxidation resistance, usually do not need to be coat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stirring Rod
A glass stirring rod, glass rod, stirring rod or stir rod is a piece of laboratory equipment used to mix chemicals. They are usually made of solid glass, about the thickness and slightly longer than a drinking straw, with rounded ends. Structure Stir rods are generally made of borosilicate (commonly known as Pyrex) glass or polypropylene plastic. They are usually between 10 and 40 centimeters in length and about half a centimeter in diameter. Glass rods are created from a single length of thin glass that is then cut into smaller segments. The ends are generally rounded (for example, by flame polishing) to prevent scratching the surface of glassware during use, which may lead to cracks if the glassware is later heated. Other shapes are possible, such as a flat paddle which can be used to circulate sediment, a triangular paddle to imitate a rubber policeman or a round button used to crush solids. Uses A stirring rod is used for mixing liquids, or solids and liquids. Stir rods ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shaker (laboratory)
A shaker is a piece of laboratory equipment used to mix, blend, or agitate substances in a tube or flask by shaking them. It is mainly used in the fields of chemistry and biology. A shaker contains an oscillating board that is used to place the flasks, beakers, or test tubes. Although the magnetic stirrer has lately come to replace the shaker, it is still the preferred choice of equipment when dealing with large volume substances or when simultaneous agitation is required. Types Vortex shaker Invented by Jack A. Kraft and Harold D. Kraft in 1962, a vortex shaker is a usually small device used to shake or mix small vials of liquid substance. Its most standout characteristic is that it works by the user putting a vial on the shaking platform and turning it on; thus, the vial is shaken along with the platform. A vortex shaker is very variable in terms of speed adjustment, for the shaking speed can be continuously changed while shaking by turning a switch. Platform shaker A pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscosity
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's axis than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the strength of the compensating force is proportional to the fluid's viscosity. In general, viscosity depends on a fluid's state, such as its temperature, pressure, and rate of deformation. However, the dependence on some of these properties is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to the magnetic field. A permanent magnet's magnetic field pulls on ferromagnetic materials such as iron, and attracts or repels other magnets. In addition, a nonuniform magnetic field exerts minuscule forces on "nonmagnetic" materials by three other magnetic effects: paramagnetism, diamagnetism, and antiferromagnetism, although these forces are usually so small they can only be detected by laboratory equipment. Magnetic fields surround magnetized materials, and are created by electric currents such as those used in electromagnets, and by electric fields varying in time. Since both strength and direction of a magnetic field may vary with location, it is described mathematically by a function assigning a vector to each point of space, cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of the molten form; some glasses such as volcanic glass are naturally occurring. The most familiar, and historically the oldest, types of manufactured glass are "silicate glasses" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. Soda–lime glass, containing around 70% silica, accounts for around 90% of manufactured glass. The term ''glass'', in popular usage, is often used to refer only to this type of material, although silica-free glasses often have desirable properties for applications in modern communications technology. Some objects, such as drinking glasses and eyeglasses, are so commonly made of silicate-based glass that they are simply called by the name of the material. Despite bei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Stirrer
A magnetic stirrer or magnetic mixer is a laboratory device that employs a rotating magnetic field to cause a stir bar (or ''flea'') immersed in a liquid to spin very quickly, thus stirring it. The rotating field may be created either by a rotating magnet or a set of stationary electromagnets, placed beneath the vessel with the liquid. It is used in chemistry and biology as a convenient way to stir small volumes and where other forms of stirring, such as overhead stirrers and stirring rods, may not be viable. Design file:Magnetic Stir Bars.JPG, left, Four magnetic stir bars next to a metre stick A magnetic stirrer consists of a magnetic bar placed within the liquid which provides the stirring action. The stir bar's motion is driven by another rotating magnet or assembly of electromagnets in the stirrer device, beneath the vessel containing the liquid. Stir bars are typically coated in PTFE, or, less often, in glass; the coatings are intended to be chemically inert, not contam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Stirring Bars Aligned
Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particles give rise to a magnetic field, which acts on other currents and magnetic moments. Magnetism is one aspect of the combined phenomena of electromagnetism. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves. Demagnetizing a magnet is also possible. Only a few substances are ferromagnetic; the most common ones are iron, cobalt, and nickel and their alloys. The rare-earth metals neodymium and samarium are less common examples. The prefix ' refers to iron because permanent magnetism was first observed in lodestone, a form of natural iron ore called magnetite, Fe3O4. All substances exhibit some type of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenock
Greenock (; sco, Greenock; gd, Grianaig, ) is a town and administrative centre in the Inverclyde council areas of Scotland, council area in Scotland, United Kingdom and a former burgh of barony, burgh within the Counties of Scotland, historic county of Renfrewshire (historic), Renfrewshire, located in the west central Lowlands of Scotland. It forms part of a contiguous urban area with Gourock to the west and Port Glasgow to the east. The United Kingdom Census 2011, 2011 UK Census showed that Greenock had a population of 44,248, a decrease from the 46,861 recorded in the United Kingdom Census 2001, 2001 UK Census. It lies on the south bank of the Clyde at the "Tail of the Bank" where the River Clyde deepens into the Firth of Clyde. History Name Place-name scholar William J. Watson wrote that "Greenock is well known in Gaelic as Grianáig, dative of grianág, a sunny knoll". The Scottish Gaelic place-name ''Grianaig'' is relatively common, with another (Greenock) near Calla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpedo Experimental Establishment
The Torpedo Experimental Establishment (T.E.E.) also known as the Admiralty Torpedo Experimental Establishment was a former research department of the British Department of Admiralty from 1947 to 1959. It was responsible for the design, development and production of torpedoes for the Royal Navy. In 1959 its work and staff merged with the Admiralty Underwater Weapons Establishment. The department was administered by the Superintendent, Torpedo Experiment and Design. History Research into the development of torpedoes first occurred during the end of the 19th century. Initially this took place at the Royal Gun Factory, Woolwich. Further research work was then undertaken at the Royal Naval Torpedo Factory, Greenock, Scotland with additional torpedo experimentation being undertaken by a private contractor, the Whitehead Torpedo Company based in Weymouth, Dorset. In 1937, the Admiralty acquired another factory at Alexandria, Scotland, to boost production. With the advent of World War ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lubricant
A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, transporting foreign particles, or heating or cooling the surfaces. The property of reducing friction is known as lubricity. In addition to industrial applications, lubricants are used for many other purposes. Other uses include cooking (oils and fats in use in frying pans, in baking to prevent food sticking), bioapplications on humans (e.g. lubricants for artificial joints), ultrasound examination, medical examination, and sexual intercourse. It is mainly used to reduce friction and to contribute to a better and efficient functioning of a mechanism. History Lubricants have been in some use for thousands of years. Calcium soaps have been identified on the axles of chariots dated to 1400 BC. Building stones were slid on oil-impregrated lumb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
