The Fajans Paneth Hahn Law also Fajans precipitation rule , Fajans Peneth precipitation and adsorption rule , Hahn law of precipitation and adsorption , in chemistry , is a rule governing how a small amount of one substance tracer is carried down to a precipitate of another substance present in much larger amount carrier by co precipitation or adsorption . The rule states that ref Otto Hahn, Applied Radiochemistry , Cornell University Press, Ithaca, New York, USA, 1936. ref ref W.M. Gibson, The radiochemistry of lead , National Academy of Sciences National Research Council, 1961 http library.lanl.gov cgi bin getfile?rc000004.pdf pdf . ref the lower the solubility of the tracer cation with the anion of the carrier, the greater the amount of the tracer carried down by the carrier through co precipitates or adsorption when the tracer substance forms a mixed crystal , then the separation by co precipitation only weakly depends on the conditions the tracer will adsorb on the surface of the carrier precipitate if the precipitate acquired a surface charge opposite to that of the carrier ions in the solution and then the separation strongly depends on the condition of precipitation. The amount carried down is strongly affected by presence of Coordination complex complexing species regardless if it occurs by formation of mixed crystals or adsorption. The law is named after chemists Kazimierz Fajans , Friedrich Paneth and Otto Hahn . The Fajans Paneth Hahn law is essential for understanding the behaviour of minute amounts of substances e.g., carrier free radioisotope s in solutions. Note that the tracer is precipitated from the solution even when present at concentration far below its solubility limit. The law is also applied for separation of tracer substances by co precipitation. See also Hume Rothery rules References Reflist Category Analytical chemistry Category Chemical processes Category Radiochemistry ... more details
ensure enhanced Cost Efficiency cost efficiency and incinerators production capacity. Adsorption technology File Mobile oxygen station.jpg thumb Type of performance on semitrailer Adsorption principle Gas separation by adsorption systems is based on the fixation of various gas mixture components by a solid ... oxygen production from air with the use of adsorption technology are nearly brought to perfection. The operation of a modern oxygen adsorption plant is based on the dependence of gas intake by adsorbent on the temperature and partial pressure of a gas component. The gas adsorption and adsorbent .... Pressure swing adsorption The oxygen plant flow process is arranged in such a way that highly ... components go through the plant. Today, there exist three methods of arranging the adsorption based ... ones. In the pressure swing adsorption flow processes, oxygen is recovered under above atmospheric pressure and regeneration is achieved under atmospheric pressure . In vacuum swing adsorption flow ... from positive to negative. Adsorption oxygen plants The adsorption oxygen plants produce 5 to 5,000 ... produce gaseous oxygen from atmospheric air. An unquestionable advantage of adsorption ... to the product oxygen purity. Structurally, the adsorption oxygen plant consists of several adsorbers ... at the level of 90 95 with the capacity of up to 5,000 nm3 per hour, adsorption oxygen plants ... systems generally prove more economically sound than adsorption and cryogenic systems. Besides, membrane plants are much simpler in operation and more reliable. Advantages of adsorption and membrane ... purity 93 95 for adsorption and 30 45 for membrane plants Limited capacity. External links http ... more details
HEGA is an acronym for H igh E fficiency G as A bsorption . Originally developed by the British military as a defense against chemical warfare , HEGA is a carbon cloth filter. This carbon cloth has been claimed to be many times more efficient than the granular activated carbon form at adsorption of gaseous pollutants. With its light weight and easy workability , HEGA filters are now used in some residential air purifier s. See also HEPA Air purifier Category Filters tech stub es HEGA ... more details
Multiple issues orphan February 2009 context October 2009 unreferenced July 2007 SESOIL SEasonal SOIL is a one dimensional vertical transport screening level model for the unsaturated Vadose zone vadose zone. It simulates contaminant transport and fate based on diffusion , adsorption , volatilization , biodegradation , and hydrolysis . SESOIL is a public domain program written in FORTRAN developed in 1981 by the United States Environmental Protection Agency USEPA , written by Bonazountas and Wagner of the Arthur D. Little corporation. Category Hydrology Science software stub ... more details
Scheutjens Fleer theory is a lattice based Mean field theory self consistent field theory that is the basis for many computational analyses of polymer adsorption . References Polymers at Interfaces by G.J. Fleer, M.A. Cohen Stuart, J.M.H.M. Scheutjens, T. Cosgrove, B. Vincent. ISBN 9780412581601 condensedmatter stub Category Polymer chemistry Category Solutions Category Thermodynamics Category Statistical mechanics ... more details
Orphan date January 2011 Palladium black is a coarse, sponge like form of elemental palladium that offers a large surface area for hydrogen adsorption . It can be used as a catalyst for hydrogenation reactions. This term is also used colloquially to refer to a black precipitate of elemental palladium, which forms on decomposition of palladium complexes. This form of palladium is commercially available in different grades. ref For example, Aldrich 205834 ref It may be prepared by the reduction of various palladium II compounds. References references Category Palladium chem stub ... more details
Vanir Energy is a renewable energy company located in Fletcher, North Carolina . Vanir Energy completed the largest solar heating and cooling project in the world in February 2009. http www.solarthermalworld.org node 406 Installed on Fletcher Business Park, Vanir used 640 solar thermal collectors and 2 150 ton adsorption chillers from Japan for the project. Category Solar energy companies of the United States Category Renewable energy in the United States ... more details
Paneth may refer to Fajans Paneth Hahn Law , a chemistry rule concerning co precipitation and adsorption Friedrich Paneth 1887&ndash 1958 , an Austrian born British chemist Joseph Paneth 1857&ndash 1890 , an Austrian physiologist from Vienna Paneth crater , a lunar impact crater that is located on the far side of the Moon Paneth cell , found in the intestinal tract disambig de Paneth ... more details
Saturated surface dry SSD Citation needed date July 2011 is defined as the condition of an aggregate composite aggregate in which the surfaces of the particles are saturated i.e. , surface adsorption would no longer take place , but the porosity inter particle voids are otherwise dry. In this condition aggregates will not affect the free water content of a composite material . ref cite web url http www.cement.org tech faq saturated.asp title What is meant by saturated surface dry condition of aggregates? publisher cement.org accessdate 2011 07 02 ref ref ftp ftp.dot.state.tx.us pub txdot info cst TMS 400 A series pdfs cnn403.pdf ref If the mass of an oven dried test sample M sub dry sub is compared to the mass of a saturated surface dry M sub ssd sub sample, the water adsorption A can be calculated math A frac M ssd M dry M dry math See also Construction aggregate References Reflist DEFAULTSORT Saturated Surface Dry Category Concrete Category Building materials Category Materials material stub ... more details
The electrochemical regeneration of activated carbon based adsorption adsorbents involves the removal of molecules adsorbed onto the surface of the adsorbent with the use of an electric current in an electrochemical cell restoring the carbon s adsorptive capacity. Electrochemical regeneration represents an alternative to activated carbon Regeneration thermal regeneration commonly used in waste water treatment applications. Common adsorbents include powdered activated carbon PAC , granular activated carbon GAC and activated carbon fibre. Regeneration for adsorbent re use In waste water treatment, the most commonly used adsorbent is granular activated carbon GAC , often used as to treat both liquid and gas phase volatile organic compounds and organic compound organic pollutants. ref Cite journal last Moreno Castilla first C authorlink coauthors title Adsorption of organic molecules from aqueous solutions on carbon materials journal Carbon volume 42 issue pages 83 94 publisher location year ... of the pollutant s being removed, their associated adsorption Isotherms adsorption isotherms ... activated carbons Once the adsorptive capacity of the activated carbon bed has been exhausted by the adsorption ... affect the adsorption equilibrium and have been shown to promote desorption of organic pollutants ... before adsorption adsorptive capacity after adsorption and electrochemical regeneration times 100 ... oxidising nature of the anode. ref name zhang Repeated adsorption regeneration For the bulk of carbonaceous ... blockages and damage to adsorption sites by the applied current. Decreases in regeneration efficiency ... Roberts, E. P. L., Chasiotis, A., Cherdron, T., & Sanghrajka, N title Atrazine removal using adsorption ... number of commercially available carbon based adsorption electrochemical regeneration systems. One system that does exist uses a carbon adsorbent called Nyex in a Continuous Adsorption Regeneration continuous adsorption regeneration system that uses electrochemical regeneration to adsorb and destroy ... more details
Image Surface specifique et rayures.svg thumb Scratches, represented by triangular shaped grooves, make the surface area bigger Specific surface area is a material property of solid s which measures the total surface area per unit of mass ref http goldbook.c60.kiev.ua S05806.pdf IUPAC Compendium of Chemical Terminology 2nd Edition 1997 ref , solid or bulk volume ref http web.archive.org web 20060905224652 http www.soils.wisc.edu ss322 lectures lec 8 11.pdf ref , or cross sectional area It is a derived scientific value that can be used to determine the type and properties of a material e.g. soil . It is defined either by surface area divided by mass with units of m kg , or surface area divided by the volume units of m m or m sup 1 sup It has a particular importance for adsorption , heterogeneous catalysis , and reactions on surfaces . Measurement The value obtained for specific surface area depends critically upon the method of measurement. Calculation The SSA can be simply calculated from a particle size distribution , making some assumption about the particle shape. This method, however, fails to account for surface associated with the surface texture of the particles. Adsorption The SSA can be measured by adsorption using the BET theory BET isotherm . This has the advantage of measuring the surface of fine structures and deep texture on the particles. However, the results can differ markedly depending on the substance adsorbed. Gas permeability main Air permeability specific surface This depends upon a relationship between the specific surface area and the resistance to gas flow of a porous bed of powder. The method is simple and quick, and yields a result that often correlates well with the chemical reactivity of a powder. However, it fails to measure much of the deep surface texture. See also Surface area to volume ratio References references engineering stub Category Porous media Category Surface chemistry de Innere Oberfl che et Eripind es Superficie espec fic ... more details
wiktionary Langmuir may refer to Langmuir crater , an impact crater on the Moon s far side Langmuir journal Langmuir journal , an academic journal on colloids, surfaces and interfaces, published by the American Chemical Society Langmuir unit , a unit of exposure of an adsorbate gas to a substrate used in surface science to study adsorption Langmuir Cove , a cove in the north end of Arrowsmith Peninsula, Graham Land, Antarctica People Alexander Langmuir 1910 1993 , an American epidemiologist Charles Langmuir , a geologist and nephew of Irving Langmuir Gavin I. Langmuir 1924 2005 , a Canadian veteran of World War II, an historian of anti Semitism and a medievalist at Stanford University Irving Langmuir 1881 1957 , an American Nobel Prize winning chemist and physicist known for Irving Langmuir House Langmuir circulation , a wind driven ocean circulation Langmuir equation , an equation that relates the coverage or adsorption of molecules on a solid surface to gas pressure or concentration of a medium above the solid surface at a fixed temperature Langmuir probe Langmuir wave , a rapid oscillation of the electron density in conducting media such as plasmas or metals disambiguation de Langmuir fr Langmuir nl Langmuir zh ... more details
Unreferenced stub auto yes date December 2009 Orphan date December 2009 In physical chemistry , a hot atom is an atom that has a high translational energy . When molecule AB Adsorption adsorbs on a surface dissociatively, both A and B adsorb on the surface, or only A adsorbs on the surface, and B desorbs from the surface. In case 2, B gains a high translational energy from the adsorption energy of A, and hot atom B is generated. For example, the hydrogen molecule , because of its light mass, gets a high translational energy. Such a hot atom does not fly into vacuum but is trapped on the surface, where it diffuses with high energy. Hot atoms are expected to play important roles in catalysis catalytic reactions . For example, a reaction of a hydrogen atom with hydrogen atoms on a silicon surface and a reaction of an oxygen atom with oxygen molecules on Platinum Pt 111 have been reported. Hot atoms can also be generated by degenerating molecules on a metal surface with Ultraviolet UV light. It has been reported that the reactivity of an oxygen atom generated in such a way on a platinum surface is different from that of chemisorbed oxygen atoms. Elucidating the role of hot atoms on surfaces will lead to a deeper understanding of the mechanism of reactions. DEFAULTSORT Hot Atom Category Physical chemistry Chem stub ar ... more details
orphan date September 2009 Company Information MicroVacuum Ltd. is a Hungarian high tech company. MicroVacuum is a global supplier of label free biosensor systems for the Biology life science research market to provide rapid, real time, label free detection and characterization of surface adsorption, binding of molecules. MicroVacuum develops, manufactures and markets the OWLS label free, real time biosensor system based on the grating coupler waveguide technology. The OW optical sensors and OWLS analytical system allow the determination of the affinity and kinetics of a wide variety of molecular interactions in real time, without the need for a molecular tag or label. Applications include protein quantification, classification of protein protein and protein DNA interactions, Drug test drug screening , immunosensing and many more. MicroVacuum has customers all over the world including prominent universities in the United States , Europe, Australia and Asia. The main biosensing applications of the OWLS technology are as follows Adsorption of proteins at surfaces Immunosensing Drug screening Ligand receptor binding Kinetics of adhesion, growth and spreading of living cells Protein lipid bilayer interactions Protein DNA interactions Molecular self assembly & nanoscience Analysis of association and dissociation kinetics Relevant sites http www.owls sensors.com Category Companies of Hungary Category Biotechnology Category Sensors ... more details
web title Development of Pressure Swing Adsorption url http humanresearchroadmap.nasa.gov tasks ... of a nitrogen generator utilizing the adsorption technology is based on the dependence of the adsorption ... nitrogen adsorption plants of various types, pressure swing adsorption PSA plants have found the broadest application world wide. The system s design is based on the regulation of gas adsorption and adsorbent ... at below atmospheric pressure. The swing adsorption process in each of the two adsorbers consists of two stages running for a few minutes. At the adsorption stage Oxygen, H sub 2 sub O and CO sub 2 sub ... repeated. ref cite web title How do Pressure Swing Adsorption Nitrogen Generators Work? url http www.peakscientific.com news 148 how do pressure swing adsorption nitrogen generators work publisher .... Advantages Economic benefits By substitution of out of date cryogenic or adsorption systems ... more details
The Gibbs adsorption isotherm for multicomponent systems is an equation used to relate the changes in concentration ... system containing two components, the Gibbs adsorption equation in terms of surface excess is math ... sub 1 sub is the chemical potential of component 1. Adsorption Different influences at the interface ... the phenomena of adsorption . Adsorption influences changes in surface tension and colloid stability. Adsorption layers at the surface of a liquid dispersion medium may affect the interactions ... Chemistry. 3rd ed. New York Marcel Dekker, Inc, 1997. ref The adsorption of molecules of liquid ... be gas, liquid, or solid ref name Chattoraj Chattoraj, D.K. and Birdi, K.S. Adsorption and the Gibbs .... The quantitative measure of adsorption of the math i th component is captured by the surface excess ... surface excess quantities. ref name Chattoraj The Relative surface excess relates the adsorption ... alpha , C i beta , C 1 alpha , C 1 beta , right ,. math The Gibbs adsorption isotherm equation Derivation of the Gibbs adsorption equation For a two phase system consisting of the math and math phase ... of the Gibbs Adsorption Isotherm can be derived from the particularization to the thermodynamics ... d mu i , 0 ,. math The resulting equation is the Gibbs adsorption isotherm equation math sum i 1 k mathrm n i mathrm S , mathrm d mu i , A mathrm d gamma , 0 ,. math The Gibbs adsorption isotherm is an equation which could be considered an adsorption isotherm that connects surface tension of a solution ... Adsorption Equation in terms of surface excess is math mathrm d gamma Gamma 1 mathrm d mu 1 , Gamma ... s, correct this flaw. Ionic dissociation effects Gibbs equation for electrolyte adsorption ... text z mathrm z , mathrm N , mathrm a text ,. math The Gibbs Adsorption equation in terms of the relative ... of the Gibbs adsorption. ref name Chattoraj Values of math m are calculated using ... methods The extent of adsorption at a liquid interface can be evaluated using the surface ... more details
wiktionary isotherm Isotherm may refer to Isotherm contour line spaced ndash a type of contour line that connects points of equal temperature at a given date or time on a geographic map Isotherm spaced ndash in thermodynamics, a curve on a p V diagram for an isothermal process Moisture sorption isotherm spaced ndash a curve giving the functional relationship between humidity and equilibrium water content of a material for a constant temperature Sorption isotherm spaced ndash a curve giving the functional relationship between adsorbate and adsorbent in a constant temperature adsorption process disambig cs Izotermick d j Izoterma fr Isotherme pl Izoterma ru sk Izoterma ... more details
VSA may refer to Associations Fighting Dems Veterans for a Secure America Victorian Speleological Association Vietnamese Student Association The Violin Society of America Voluntary Service Aberdeen Volunteer Service Abroad VSA arts Vleegel iS Away Science and technology Vacuum swing adsorption van der Waals surface area Vector signal analyzer Electronic stability control Vehicle stability assist RADIUS Vendor specific attributes Vendor Specific Attribute Very Small Array Voice stress analysis Viable systems approach Other Carlos Rovirosa P rez International Airport IATA VSA , Mexico Vatican Secret Archives Vital signs absent disambig de VSA it VSA ... more details
Unreferenced stub auto yes date December 2009 mergeto selection rule date December 2010 Orphan date February 2009 In Vibrational spectroscopy surface vibrational spectroscopy , the surface selection rule is applied to identify the peaks observed in vibrational spectra. When a molecule is adsorption adsorbed on a substrate, the molecule induces opposite image charges in the substrate. The dipole dipole moment of the molecule and the image charges perpendicular to the surface reinforce each other. In contrast, the dipole moments of the molecule and the image charges parallel to the surface cancel out. Therefore, only molecular vibrational peaks giving rise to a dynamic dipole moment perpendicular to the surface will be observed in the vibrational spectrum. DEFAULTSORT Surface Selection Rule Category Spectroscopy Physics stub Chemistry stub ... more details
Wiktionary Sorption is a physics physical and chemistry chemical process by which one substance becomes attached to another. Specific cases of sorption are treated in the following articles Absorption chemistry Absorption the incorporation of a substance in one state into another of a different state e.g., liquid s being absorbed by a solid or gases being absorbed by a liquid Adsorption the physical adherence or bonding of ion s and molecule s onto the surface of another phase e.g., reagents adsorbed to a solid catalyst surface Ion exchange an exchange of ion s between two electrolyte s or between an electrolyte solution and a complex chemistry complex Category Physical chemistry de Sorption et Sorptsioon el fr Sorption hi id Absorpsi it Assorbimento gas liquido nl Absorptie fysische chemie no Absorpsjon ru th tk Absorbsi a uk ... more details
Refimprove date September 2007 A helium 3 refrigerator is a simple device used in experimental physics for obtaining temperature s down to about 0.2 kelvin s. By evaporative cooling of helium 4 the more common isotope of helium , a 1 K pot liquefies a small amount of helium 3 in a small vessel called a helium 3 pot. Evaporative cooling of the liquid helium 3, usually driven by adsorption since due to its high price the helium 3 is usually contained in a closed system to avoid losses, cools the helium 3 pot to a fraction of a kelvin. See also Dilution refrigerator References reflist External links http www.its.caltech.edu jpelab Group 20Website cryogenics.html Helium 3 refrigerators at Caltech Category Cryogenics Category Cooling technology thermodynamics stub ... more details
Adsorptive stripping voltammetry is similar to anodic stripping voltammetry and cathodic stripping voltammetry except that the preconcentration step is not controlled by electrolysis . The preconcentration step in adsorptive stripping voltammetry is accomplished by adsorption on the working electrode surface, or by reactions with chemically modified electrodes See also Voltammetry Electroanalytical Methods References Wang, J. 1985 . Stripping Analysis Principles, Instrumentation, and Applications, VCH Publishers, Inc., Deerfield Beach, Florida. External links http www.iupac.org publications pac 1989 pdf 6101x0097.pdf http www.prenhall.com settle chapters ch37.pdf Electroanalytical Category Electroanalytical methods analytical chemistry stub ... more details
by silica adsorption How does this method of purification work.3F separation by silica adsorption ... by silica adsorption References Reflist Molecular Biology Category Biochemistry methods Category ... more details
Zinc ricinoleate is the zinc ionic compound salt of ricinoleic acid , a major fatty acid found in castor oil . It is used in many deodorant s as an odor adsorbing agent. The mechanism of this activity is unclear. ref cite journal last Kuhn first H. coauthors F. M ller, J. Peggau, R. Zekorn date April 18, 2000 title Mechanism of the odor adsorption effect of zinc ricinoleate. A molecular dynamics computer simulation journal Journal of Surfactants and Detergents volume 3 pages 335 343 publisher Springer Berlin Heidelberg issn 1097 3958 doi 10.1007 s11743 000 0137 9 url http www.springerlink.com content q17655204020tw43 ref Reflist References Category Zinc compounds Category Personal hygiene products pt Ricinoleato de zinco ... more details
in other words, requires higher temperatures because the rate of adsorption is slow and rate ... of &Delta H sub f sub , with the rate being a combination of the rate of adsorption and the rate of desorption ... more details
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