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Fractionation
Fractionation is a separation process in which a certain quantity of a mixture (of gases, solids, liquids, enzymes, or isotopes, or a suspension) is divided during a phase transition, into a number of smaller quantities (fractions) in which the composition varies according to a gradient. Fractions are collected based on differences in a specific property of the individual components. A common trait in fractionations is the need to find an optimum between the amount of fractions collected and the desired purity in each fraction. Fractionation makes it possible to isolate more than two components in a mixture in a single run. This property sets it apart from other separation techniques. Fractionation is widely employed in many branches of science and technology. Mixtures of liquids and gases are separated by fractional distillation by difference in boiling point. Fractionation of components also takes place in column chromatography by a difference in affinity between stationary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fractional Distillation
Fractional distillation is the separation of a mixture into its component parts, or fractions. Chemical compounds are separated by heating them to a temperature at which one or more fractions of the mixture will vaporize. It uses distillation to fractionate. Generally the component parts have boiling points that differ by less than 25 °C (45 °F) from each other under a pressure of one atmosphere. If the difference in boiling points is greater than 25 °C, a simple distillation is typically used. It is used to refine crude oil. Laboratory setup Fractional distillation in a laboratory makes use of common laboratory glassware and apparatuses, typically including a Bunsen burner, a round-bottomed flask and a condenser, as well as the single-purpose fractionating column. As an example, consider the distillation of a mixture of water and ethanol. Ethanol boils at while water boils at . So, by heating the mixture, the most volatile component (ethanol) will ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Transition
In chemistry, thermodynamics, and other related fields, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic states of matter: solid, liquid, and gas, and in rare cases, plasma. A phase of a thermodynamic system and the states of matter have uniform physical properties. During a phase transition of a given medium, certain properties of the medium change as a result of the change of external conditions, such as temperature or pressure. This can be a discontinuous change; for example, a liquid may become gas upon heating to its boiling point, resulting in an abrupt change in volume. The identification of the external conditions at which a transformation occurs defines the phase transition point. Types of phase transition At the phase transition point for a substance, for instance the boiling point, the two phases involved - liquid and vapor, have id ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Fractionation
In cell biology, cell fractionation is the process used to separate cellular components while preserving individual functions of each component. This is a method that was originally used to demonstrate the cellular location of various biochemical processes. Other uses of subcellular fractionation is to provide an enriched source of a protein for further purification, and facilitate the diagnosis of various disease states. Homogenization Tissue is typically homogenized in a buffer solution that is isotonic to stop osmotic damage. Mechanisms for homogenization include grinding, mincing, chopping, pressure changes, osmotic shock, freeze-thawing, and ultra-sound. The samples are then kept cold to prevent enzymatic damage. It is the formation of homogenous mass of cells (cell homogenate or cell suspension). It involves grinding of cells in a suitable medium in the presence of certain enzymes with correct pH, ionic composition, and temperature. For example, pectinase which diges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fractional Distillation Lab Apparatus
A fraction is one or more equal parts of something. Fraction may also refer to: * Fraction (chemistry), a quantity of a substance collected by fractionation * Fraction (floating point number), an (ambiguous) term sometimes used to specify a part of a floating point number * Fraction (politics), a subgroup within a parliamentary party * Fraction (radiation therapy), one unit of treatment of the total radiation dose of radiation therapy that is split into multiple treatment sessions * Fraction (religion), the ceremonial act of breaking the bread during Christian Communion People with the surname * Matt Fraction, a comic book author See also * Algebraic fraction, an indicated division in which the divisor, or both dividend and divisor, are algebraic expressions ** Irrational fraction, a type of algebraic fraction * Faction (other) * ''Frazione'', a type of administrative division of an Italian ''commune'' * Free and Independent Fraction, a Romanian political party * Par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milk Basic Protein
Milk basic protein (MBP) is a fraction of whey protein found in milk.Möller, N.P., Scholz-Ahrens, K.E., Roos, N., & Schrezenmeir, J. (2008). Bioactive peptides and proteins from foods: indication for health effects. ''European Journal of Nutrition, 47''(4), 176. Separated from milk through the process of fractionation, it is a functional compound and consists of several milk proteins which are biologically active. The composition is approximately 54% lactoferrin and 41% lactoperoxidase,Kruger, C.L., Marano, K.M., Morita, Y., Takada, Y., Kawakami, H., Kobayashi, T., Sunaga, M., Furukawa, M., & Kawamura, K. (2007). Safety evaluation of a milk basic protein fraction. ''Food and Chemical Toxicology, 45'', 1301. with other active proteins, such as Cyastin C and high mobility group-like proteins, making up the remainder of the fraction.Goodman, R., Taylor, S., Yamamura, J., Kobayashi, T., Kawakami, H., Kruger, C., & Thompson, G. (2007). Assessment of the potential allergenicity of a Milk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milk Protein Concentrate
Milk protein concentrate (MPC) is any type of concentrated milk product that contains 40–90% milk protein. The United States officially defines MPC as "any complete milk protein (casein plus lactalbumin) concentrate that is 40 percent or more protein by weight." In addition to ultrafiltered milk products, the MPC classification includes concentrates made through other processes, such as blending nonfat dry milk with highly concentrated proteins, such as casein. Processing To make milk protein concentrate, whole milk is first separated into cream and skim milk. The skim milk is then fractionated using ultrafiltration to make a skim concentrate that is lactose-reduced. This process separates milk components according to their molecular size. Milk then passes through a membrane that allows some of the lactose, minerals, and water to cross through. The casein and whey proteins, however, will not pass through the membrane due to their larger molecular size. The proteins, lactos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palm Kernel Oil
Palm kernel oil is an edible plant oil derived from the kernel of the oil palm tree ''Elaeis guineensis''. It is related to other two edible oils: ''palm oil'', extracted from the fruit pulp of the oil palm, and ''coconut oil'', extracted from the kernel of the coconut. Palm kernel oil, palm oil, and coconut oil are three of the few highly saturated vegetable fats; these oils give the name to the 16-carbon saturated fatty acid palmitic acid that they contain. Palm kernel oil, which is semi-solid at room temperature, is more saturated than palm oil and comparable to coconut oil. History Oil from the African oil palm ''Elaeis guineensis'' has long been recognized in West African countries. European merchants trading with West Africa occasionally purchased palm oil for use in Europe, but palm kernel oil remained rare outside West Africa. The USDA has published historical production figures for palm kernel oil for years beginning October 1 and ending September 30: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palm Oil
Palm oil is an edible vegetable oil derived from the mesocarp (reddish pulp) of the fruit of the oil palms. The oil is used in food manufacturing, in beauty products, and as biofuel. Palm oil accounted for about 33% of global oils produced from oil crops in 2014. Palm oils are easier to stabilize and maintain quality of flavor and consistency in processed foods, so are frequently favored by food manufacturers. On average globally, humans consumed 7.7 kg (17 lb) of palm oil per person in 2015. Demand has also increased for other uses, such as cosmetics and biofuels, creating more demand on the supply encouraging the growth of palm oil plantations in tropical countries. The use of palm oil has attracted the concern of environmental groups due to deforestation in the tropics where palms are grown, and has been cited as a factor in social problems due to allegations of human rights violations among growers. An industry group formed in 2004 to create more sustainable an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coconut Oil
frameless , right , alt = A cracked coconut and a bottle of coconut oil Coconut oil (or coconut butter) is an edible oil derived from the wick, meat, and milk of the coconut palm fruit. Coconut oil is a white solid fat; in warmer climates during the summer months it is a clear thin liquid oil, melting at warmer room temperatures of around . Unrefined varieties have a distinct coconut aroma. It is used as a food oil, and in industrial applications for cosmetics and detergent production. Due to its high levels of saturated fat, numerous health authorities recommend limiting its consumption as a food.Media summary: Production Oil production is dependent upon palm cultivation. Oil production is thus threatened by coconut pests. This means most significantly the ''Oryctes'' rhinoceros beetles especially the Asiatic Rhinoceros Beetle ('' O. rhinoceros'') and the Red Palm Weevil ('' Rhynchophorus ferrugineus''). Coconut oil can be extracted through a wet or dry process. M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fractional Freezing
Fractional freezing is a process used in process engineering and chemistry to separate substances with different melting points. It can be done by partial melting of a solid, for example in zone refining of silicon or metals, or by partial crystallization of a liquid, as in freeze distillation, also called normal freezing or progressive freezing. The initial sample is thus fractionated ( separated into fractions). Partial crystallization can also be achieved by adding a dilute solvent to the mixture, and cooling and concentrating the mixture by evaporating the solvent, a process called solution crystallization. Fractional freezing is generally used to produce ultra-pure solids, or to concentrate heat-sensitive liquids. Freeze distillation Freeze distillation is a misnomer, because it is not distillation but rather a process of enriching a solution by partially freezing it and removing frozen material that is poorer in the dissolved material than is the liquid portion left be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stationary Phase (chemistry)
In chemical analysis, chromatography is a laboratory technique for the separation of a mixture into its components. The mixture is dissolved in a fluid solvent (gas or liquid) called the ''mobile phase'', which carries it through a system (a column, a capillary tube, a plate, or a sheet) on which a material called the ''stationary phase'' is fixed. Because the different constituents of the mixture tend to have different affinities for the stationary phase and are retained for different lengths of time depending on their interactions with its surface sites, the constituents travel at different apparent velocities in the mobile fluid, causing them to separate. The separation is based on the differential partitioning between the mobile and the stationary phases. Subtle differences in a compound's partition coefficient result in differential retention on the stationary phase and thus affect the separation. Chromatography may be preparative or analytical. The purpose of preparati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
