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Craig Tube
A Craig tube is an item of apparatus used in small-scale (up to about 100 mg) preparative and analytical chemistry, particularly for recrystallisation. It was invented by Lyman C. Craig and Otto W. Post. A Craig tube consists of two parts. The first is a stout-walled test tube with a working volume of about 1-5 ml (say, 7-8 cm in length and 1-1.5 cm in diameter). There is a constriction towards the open end of the tube. The second is a loosely-fitting generally-cylindrical stopper, possibly with a teardrop-shaped head, of glass or of another inert material such as PTFE, which seats on the constriction. Recrystallisation is carried out in the usual manner, by dissolving the solid to be purified in a solvent and causing crystals of the solid to form. The stopper can be used to protect the solution from atmospheric contamination. The crystals are separated from the mother liquor by placing the tube and stopperinvertedin a centrifuge tube, followed by centrifugation ...
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Recrystallization (chemistry)
In chemistry, recrystallization is a technique used to purify chemicals. By dissolving a mixture of a compound and impurities in an appropriate solvent, either the desired compound or impurities can be removed from the solution, leaving the other behind. It is named for the crystals often formed when the compound precipitates out. Alternatively, ''recrystallization'' can refer to the natural growth of larger ice crystals at the expense of smaller ones. Chemistry In chemistry, recrystallization is a procedure for purifying compounds. The most typical situation is that a desired "compound A" is contaminated by a small amount of "impurity B". There are various methods of purification that may be attempted (see Separation process), recrystallization being one of them. There are also different recrystallization techniques that can be used such as: Single-solvent recrystallization Typically, the mixture of "compound A" and "impurity B" is dissolved in the smallest amount of hot ...
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Lyman C
Lyman may refer to: Places Ukraine * Lyman, Ukraine United States * Lyman, Iowa * Lyman, Maine * Lyman, Mississippi * Lyman, Nebraska * Lyman, New Hampshire * Lyman, Oklahoma * Lyman, South Carolina * Lyman, South Dakota * Lyman County, South Dakota * Lyman, Utah * Lyman, Washington * Lyman, Wyoming Other uses * Lyman (crater), a lunar impact crater * Lyman (name) * Lyman series of hydrogen spectral lines See also * Liman (other) Liman may refer to: Places * Liman, Azerbaijan, a city in Lankaran Rayon * Liman, Davachi, a village in Shabran Rayon, Azerbaijan *Liman, Israel, a moshav in northern Israel * Liman, Russia, name of several inhabited localities in Russia *Liman, N ... * Lyman High School (other) * {{disambiguation, geo ...
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Industrial & Engineering Chemistry Research
''Industrial & Engineering Chemistry Research'' is a peer-reviewed scientific journal published by the American Chemical Society covering all aspects of chemical engineering. The editor-in-chief is Phillip E. Savage ( Pennsylvania State University). History The journal was established in 1909 as the ''Journal of Industrial & Engineering Chemistry''. It was renamed in 1930 as ''Industrial & Engineering Chemistry'' before obtaining its current title in 1970. From 1911 to 1916 it was edited by Milton C. Whitaker. From 1921 to 1942 it was edited by Dr. Harrison E. Howe. The journal ''I&EC Product Research and Development'' was established in 1962. It was renamed ''Product R&D'' in 1969 and renamed again in 1978 as ''Industrial & Engineering Chemistry Product Research and Development''. In 1986, it and the journals ''Industrial & Engineering Chemistry Fundamentals'' and ''Industrial & Engineering Chemistry Process Design and Development'', both also established in 1962, were combi ...
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Test Tube
A test tube, also known as a culture tube or sample tube, is a common piece of laboratory glassware consisting of a finger-like length of glass or clear plastic tubing, open at the top and closed at the bottom. Test tubes are usually placed in special-purpose racks. Types and usage Chemistry Test tubes intended for general chemical work are usually made of glass, for its relative resistance to heat. Tubes made from expansion-resistant glasses, mostly borosilicate glass or fused quartz, can withstand high temperatures up to several hundred degrees Celsius. Chemistry tubes are available in a multitude of lengths and widths, typically from 10 to 20 mm wide and 50 to 200 mm long. The top often features a flared lip to aid pouring out the contents. A chemistry test tube typically has a flat bottom, a round bottom, or a conical bottom. Some test tubes are made to accept a ground glass stopper or a screw cap. They are often provided with a small ground glass or white g ...
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PTFE
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. It is one of the best-known and widely applied PFAS. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a spin-off from DuPont, which originally discovered the compound in 1938. Polytetrafluoroethylene is a fluorocarbon solid, as it is a high- molecular-weight polymer consisting wholly of carbon and fluorine. PTFE is hydrophobic: neither water nor water-containing substances wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low electric polarizability of fluorine. PTFE has one of the lowest coefficients of friction of any solid. Polytetrafluoroethylene is used as a non-stick coating for pans and other cookware. It is non-reactive, partly because of the strength of carbon–fluorine bonds, so it is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubric ...
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Mother Liquor
The mother liquor (or spent liquor) is the solution remaining after a component has been removed by a some process such as filtration or more commonly crystallization. It is encountered in chemical processes including sugar refining. In crystallization, a solid (usually impure) is dissolved in a solvent at high temperature, taking advantage of the fact that most solids are more soluble at higher temperatures. As the solution cools, the solubility of the solute in the solvent will gradually become smaller. The resultant solution is described as supersaturated, meaning that there is more solute dissolved in the solution than would be predicted by its solubility at that temperature. Crystallization can then be induced from this supersaturated solution and the resultant pure crystals removed by such methods as filtration Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure throug ...
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Centrifugation
Centrifugation is a mechanical process which involves the use of the centrifugal force to separate particles from a solution according to their size, shape, density, medium viscosity and rotor speed. The denser components of the mixture migrate away from the axis of the centrifuge, while the less dense components of the mixture migrate towards the axis. Chemists and biologists may increase the effective gravitational force of the test tube so that the precipitate (pellet) will travel quickly and fully to the bottom of the tube. The remaining liquid that lies above the precipitate is called a supernatant or supernate. There is a correlation between the size and density of a particle and the rate that the particle separates from a heterogeneous mixture, when the only force applied is that of gravity. The larger the size and the larger the density of the particles, the faster they separate from the mixture. By applying a larger effective gravitational force to the mixture, like a ...
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Filter Paper
Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine solid particles from liquids or gases. The raw materials are different Pulp (paper), paper pulps. The pulp may be made from softwood, hardwood, fiber crops, Mineral fibers, mineral fibers. Properties Filter paper has various properties. The important parameters are wet strength, porosity, particle retention, volumetric flow rate, compatibility, efficiency and capacity. There are two mechanisms of filtration with paper; volume, and surface. By volume filtration, the particles are caught in the bulk of the filter paper. By surface filtration, the particles are caught on the paper surface. Filter paper is mostly used because of the ability of a small piece of filter paper to absorb a significant volume of liquid. Manufacture The raw materials are different pulp (paper), paper pulps. The pulp may be from softwood, hardwood, fiber crops, mineral fibres, mineral fiber ...
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Sintered Glass Filter
Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filter medium are described as ''oversize'' and the fluid that passes through is called the ''filtrate''. Oversize particles may form a filter cake on top of the filter and may also block the filter lattice, preventing the fluid phase from crossing the filter, known as ''blinding''. The size of the largest particles that can successfully pass through a filter is called the effective ''pore size'' of that filter. The separation of solid and fluid is imperfect; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size, filter thickness and biological activity). Filtration occurs both in nature and in engineered systems; there are biological, geological, and industrial forms. Filtration is ...
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McMaster University
McMaster University (McMaster or Mac) is a public research university in Hamilton, Ontario, Canada. The main McMaster campus is on of land near the residential neighbourhoods of Ainslie Wood and Westdale, adjacent to the Royal Botanical Gardens. It operates six academic faculties: the DeGroote School of Business, Engineering, Health Sciences, Humanities, Social Science, and Science. It is a member of the U15, a group of research-intensive universities in Canada. The university bears the name of William McMaster, a prominent Canadian senator and banker who bequeathed C$900,000 to its founding. It was incorporated under the terms of an act of the Legislative Assembly of Ontario in 1887, merging the Toronto Baptist College with Woodstock College. It opened in Toronto in 1890. Inadequate facilities and the gift of land in Hamilton prompted its relocation in 1930. The Baptist Convention of Ontario and Quebec controlled the university until it became a privately chartered, ...
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University Of Toronto
The University of Toronto (UToronto or U of T) is a public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution of higher learning in Upper Canada. Originally controlled by the Church of England, the university assumed its present name in 1850 upon becoming a secular institution. As a collegiate university, it comprises eleven colleges each with substantial autonomy on financial and institutional affairs and significant differences in character and history. The university maintains three campuses, the oldest of which, St. George, is located in downtown Toronto. The other two satellite campuses are located in Scarborough and Mississauga. The University of Toronto offers over 700 undergraduate and 200 graduate programs. In all major rankings, the university consistently ranks in the top ten public universities in the world and as the top ...
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Kindle Direct Publishing
Kindle Direct Publishing is Amazon.com's e-book publishing platform launched in November 2007, concurrently with the first Amazon Kindle device. Originally called Digital Text Platform, the platform allows authors and publishers to publish their books to the Kindle Store. Authors can upload documents in several formats for delivery via thKDP websiteand charge between $0.99 and $200.00 for their works. KDP accepts books in 44 languages. In 2016, Amazon also added a paperback option, and in 2021, a hardback (case laminated) option, both of which use print-on-demand technology. History Kindle Direct Publishing (KDP) was in open beta testing in late 2007. In a December 5, 2009 interview with ''The New York Times'', Amazon CEO Jeff Bezos revealed that Amazon keeps 65% of the revenue from all e-book sales for the Kindle. The remaining 35% is split between the author and publisher. In 2010, they improved the rate to 70% to compete with Apple, provided the publisher met certain co ...
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