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Cryostat
A cryostat (from ''cryo'' meaning cold and ''stat'' meaning stable) is a device used to maintain low cryogenic temperatures of samples or devices mounted within the cryostat. Low temperatures may be maintained within a cryostat by using various refrigeration methods, most commonly using cryogenic fluid bath such as liquid helium.Frank Pobell: ''Matter and Methods at Low Temperatures''. 3rd Edition, Springer 2007, Hence it is usually assembled into a vessel, similar in construction to a vacuum flask or Dewar. Cryostats have numerous applications within science, engineering, and medicine. Types Closed-cycle cryostats Closed-cycle cryostats consist of a chamber through which cold helium vapour is pumped. An external mechanical refrigerator extracts the warmer helium exhaust vapour, which is cooled and recycled. Closed-cycle cryostats consume a relatively large amount of electrical power, but need not be refilled with helium and can run continuously for an indefinite perio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Superconducting Magnet
A superconducting magnet is an electromagnet made from coils of superconducting wire. They must be cooled to cryogenic temperatures during operation. In its superconducting state the wire has no electrical resistance and therefore can conduct much larger electric currents than ordinary wire, creating intense magnetic fields. Superconducting magnets can produce stronger magnetic fields than all but the strongest non-superconducting electromagnets, and large superconducting magnets can be cheaper to operate because no energy is dissipated as heat in the windings. They are used in Magnetic resonance imaging, MRI instruments in hospitals, and in scientific equipment such as Nuclear magnetic resonance, NMR spectrometers, mass spectrometers, Fusion power, fusion reactors and particle accelerators. They are also used for levitation, guidance and propulsion in a SCMaglev, magnetic levitation (maglev) railway system being constructed in Japan. Construction Cooling During operation, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Microtome
A microtome (from the Greek ''mikros'', meaning "small", and ''temnein'', meaning "to cut") is a cutting tool used to produce extremely thin slices of material known as ''sections'', with the process being termed microsectioning. Important in science, microtomes are used in microscopy for the microscope slide, preparation of samples for observation under transmitted visible light, light or electron radiation. Microtomes use steel, glass or diamond blades depending upon the specimen being sliced and the desired thickness of the sections being cut. Steel blades are used to prepare histological sections of animal or plant tissues for light microscopy. Glass knives are used to slice sections for light microscopy and to slice very thin sections for electron microscopy. Industrial grade diamond knives are used to slice hard materials such as bone, teeth and tough plant matter for both light microscopy and for electron microscopy. Gem-quality diamond knife, diamond knives are also used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Magnetic Refrigeration
The magnetocaloric effect (MCE, from '' magnet'' and ''calorie'') is a scientific phenomenon in which certain materials warm up when a magnetic field is applied. The warming is due to changes in the internal state of the material releasing heat. When the magnetic field is removed, the material returns to its original state, reabsorbing the heat, and returning to original temperature. This can be used to achieve refrigeration, by allowing the material to radiate away its heat while in the magnetized hot state. Removing the magnetism, the material then cools to below its original temperature. The effect was first observed in 1881 by a German physicist Emil Warburg, followed by French physicist P. Weiss and Swiss physicist A. Piccard in 1917. The fundamental principle was suggested by P. Debye (1926) and W. Giauque (1927). The first working magnetic refrigerators were constructed by several groups beginning in 1933. Magnetic refrigeration was the first method developed for cool ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Superconducting Magnet
A superconducting magnet is an electromagnet made from coils of superconducting wire. They must be cooled to cryogenic temperatures during operation. In its superconducting state the wire has no electrical resistance and therefore can conduct much larger electric currents than ordinary wire, creating intense magnetic fields. Superconducting magnets can produce stronger magnetic fields than all but the strongest non-superconducting electromagnets, and large superconducting magnets can be cheaper to operate because no energy is dissipated as heat in the windings. They are used in Magnetic resonance imaging, MRI instruments in hospitals, and in scientific equipment such as Nuclear magnetic resonance, NMR spectrometers, mass spectrometers, Fusion power, fusion reactors and particle accelerators. They are also used for levitation, guidance and propulsion in a SCMaglev, magnetic levitation (maglev) railway system being constructed in Japan. Construction Cooling During operation, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Transition Temperature
In crystallography, the transition temperature is the temperature at which a material changes from one crystal state (allotrope) to another. More formally, it is the temperature at which two crystalline forms of a substance can co-exist in equilibrium. For example, when rhombic sulfur is heated above 95.6 °C, it changes form into monoclinic sulfur; when cooled below 95.6 °C, it reverts to rhombic sulfur. At 95.6 °C the two forms can co-exist. Another example is tin, which transitions from a cubic crystal below 13.2 °C to a tetragonal crystal above that temperature. In the case of ferroelectric or ferromagnetic crystals, a transition temperature may be known as the Curie temperature. See also * Crystal system In crystallography, a crystal system is a set of point groups (a group of geometric symmetries with at least one fixed point). A lattice system is a set of Bravais lattices (an infinite array of discrete points). Space groups (symmetry grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Containers
A container is any receptacle or enclosure for holding a product used in storage, packaging, and transportation, including shipping. Things kept inside of a container are protected on several sides by being inside of its structure. The term is most frequently applied to devices made from materials that are durable and are often partly or completely rigid. A container can also be considered as a basic tool, consisting of any device creating a partially or fully enclosed space that can be used to contain, store, and transport objects or materials. History Humans have used containers for at least 100,000 years, and possibly for millions of years.Clive Gamble, ''Origins and Revolutions: Human Identity in Earliest Prehistory'' (2007), p. 204. The first containers were probably invented for storing food, allowing early humans to preserve more of their food for a longer time, to carry it more easily, and also to protect it from other animals. The development of food storage co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lambda Point Refrigerator
Lambda (; uppercase , lowercase ; , ''lám(b)da'') is the eleventh letter of the Greek alphabet, representing the voiced alveolar lateral approximant . In the system of Greek numerals, lambda has a value of 30. Lambda is derived from the Phoenician Lamed. Lambda gave rise to the Latin L and the Cyrillic El (Л). The ancient grammarians and dramatists give evidence to the pronunciation as () in Classical Greek times. In Modern Greek, the name of the letter, Λάμδα, is pronounced . In early Greek alphabets, the shape and orientation of lambda varied. Most variants consisted of two straight strokes, one longer than the other, connected at their ends. The angle might be in the upper-left, lower-left ("Western" alphabets) or top ("Eastern" alphabets). Other variants had a vertical line with a horizontal or sloped stroke running to the right. With the general adoption of the Ionic alphabet, Greek settled on an angle at the top; the Romans put the angle at the lower-left. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Deli Slicer
A meat slicer, also called a slicing machine, deli slicer or simply a slicer, is a tool used in butcher shops and delicatessens to slice meats, sausages, cheeses and other deli products. As compared to a simple knife, using a meat slicer requires less effort, as well as keeps the texture of food more intact. Generally, slicers can be adjusted easily to cut slices of variable thickness. Older models of meat slicer may be operated by crank, while newer ones generally use an electric motor. While the slicer is traditionally a commercial apparatus, domestic use versions are also marketed. See also * Egg slicer * Kezuriki * Mandoline * Spiral vegetable slicer * Tomato slicer The tomato (, ), ''Solanum lycopersicum'', is a plant whose fruit is an edible berry that is eaten as a vegetable. The tomato is a member of the nightshade family that includes tobacco, potato, and chili peppers. It originated from and was d ... References {{cooking-tool-stub Food preparation appli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Frozen Section Procedure
The frozen section procedure is a pathological laboratory procedure to perform rapid microscopic analysis of a specimen. It is used most often in oncological surgery. The technical name for this procedure is cryosection. The microtome device that cold cuts thin blocks of frozen tissue is called a cryotome. The quality of the slides produced by frozen section is of lower quality than formalin fixed paraffin embedded tissue processing. While diagnosis can be rendered in many cases, fixed tissue processing is preferred in many conditions for more accurate diagnosis. The intraoperative consultation is the name given to the whole intervention by the pathologist, which includes not only frozen section but also gross evaluation of the specimen, examination of cytology preparations taken on the specimen (e.g. touch imprints), and aliquoting of the specimen for special studies (e.g. molecular pathology techniques, flow cytometry). The report given by the pathologist is often limited to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Liquid Nitrogen
Liquid nitrogen (LN2) is nitrogen in a liquid state at cryogenics, low temperature. Liquid nitrogen has a boiling point of about . It is produced industrially by fractional distillation of liquid air. It is a colorless, mobile liquid whose viscosity is about one-tenth that of acetone (i.e. roughly one-thirtieth that of water at room temperature). Liquid nitrogen is widely used as a coolant. Physical properties The diatomic character of the N2 molecule is retained after liquefaction. The weak van der Waals interaction between the N2 molecules results in little interatomic attraction. This is the cause of nitrogen's unusually low boiling point. The temperature of liquid nitrogen can readily be reduced to its freezing point by placing it in a vacuum chamber pumped by a vacuum pump. Liquid nitrogen's efficiency as a coolant is limited by the fact that it boils immediately on contact with a warmer object, enveloping the object in an insulating layer of nitrogen gas bubbles. Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
