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TOP Assay
The TOP Assay (Total Oxidizable Precursor Assay) is a laboratory method developed in 2012 that oxidatively converts (unknown) precursor compounds of perfluorocarboxylic acids (PFCAs) into the latter. This makes quantification possible. Potassium peroxodisulfate is used. This sum parameter can be used to determine the concentration of precursor compounds present by comparing the sample before and after the application of the TOP Assay. Application This method is used, for example, in the analysis of fire-fighting foams (aqueous film forming foam Firefighting foam is a foam used for fire suppression. Its role is to cool the fire and to coat the fuel, preventing its contact with oxygen, thus achieving suppression of the combustion. Firefighting foam was invented by the Moldovan engineer a ...), textiles or water samples. Blood serum can also be analyzed in this way. Neutral, anionic and cationic precursor compounds may be distinguished using an extension of the method publis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environmental Science & Technology
''Environmental Science & Technology'' is a biweekly peer-reviewed scientific journal published since 1967 by the American Chemical Society. It covers research in environmental science and environmental technology, including environmental policy. ''Environmental Science & Technology'' has a sister journal, '' Environmental Science & Technology Letters'', which publishes short communications. The editor-in-chief of ''Environmental Science & Technology'' is Prof. Julie Zimmerman (Yale University). Previous editors have been: David Sedlak (University of California, Berkeley, 2014 - 2020), James J. Morgan (California Institute of Technology; founding editor, 1967–1975), Russell F. Christman (University of North Carolina, 1975–1987), William H. Glaze (University of North Carolina, 1987–2003) and Jerald L. Schnoor (University of Iowa, 2002–2014). Abstracting and indexing According to the ''Journal Citation Reports'', the journal has a 2022 impact factor of 11.4. The journal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Peroxodisulfate
Potassium persulfate is the inorganic compound with the formula K2 S2O8. Also known as potassium peroxydisulfate, it is a white solid that is sparingly soluble in cold water, but dissolves better in warm water. This salt is a powerful oxidant, commonly used to initiate polymerizations. Structure The sodium and potassium salts are very similar. In the potassium salt, the O-O distance is 1.495Å. The individual sulfate groups are tetrahedral, with three short S-O distances near 1.43 and one long S-O bond at 1.65Å. Preparation Potassium persulfate can be prepared by electrolysis of a cold solution potassium bisulfate in sulfuric acid at a high current density. : 2 KHSO4 → K2S2O8 + H2 It can also be prepared by adding potassium bisulfate (KHSO4) to a solution of the more soluble salt ammonium peroxydisulfate (NH4)2S2O8. In principle it can be prepared by chemical oxidation of potassium sulfate using fluorine. Several million kilograms of the ammonium, sodium, and potassium sal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TOP Assay
The TOP Assay (Total Oxidizable Precursor Assay) is a laboratory method developed in 2012 that oxidatively converts (unknown) precursor compounds of perfluorocarboxylic acids (PFCAs) into the latter. This makes quantification possible. Potassium peroxodisulfate is used. This sum parameter can be used to determine the concentration of precursor compounds present by comparing the sample before and after the application of the TOP Assay. Application This method is used, for example, in the analysis of fire-fighting foams (aqueous film forming foam Firefighting foam is a foam used for fire suppression. Its role is to cool the fire and to coat the fuel, preventing its contact with oxygen, thus achieving suppression of the combustion. Firefighting foam was invented by the Moldovan engineer a ...), textiles or water samples. Blood serum can also be analyzed in this way. Neutral, anionic and cationic precursor compounds may be distinguished using an extension of the method publis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firefighting Foam
Firefighting foam is a foam used for fire suppression systems, fire suppression. Its role is to cool the fire and to coat the fuel, preventing its contact with oxygen, thus achieving suppression of the combustion. Firefighting foam was invented by the Moldovans, Moldovan engineer and chemist Aleksandr Loran in 1902.Loran and the fire extinguisher at p-lab.org The surfactants used must produce foam in concentrations of less than 1%. Other components of fire-retardant foams are organic solvents (e.g., trimethyl-1,3-Propanediol, trimethylene glycol and 2-Methyl-2,4-pentanediol, hexylene glycol), foam stabilizers (e.g., dodecanol, lauryl alcohol), and corrosion inhibitors. Overview * Low-expansion foams, such as aqueous film forming foams (AFFFs), have an expansion ratio of less than 20, are low-viscosity, mobile, ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laboratory Techniques
A laboratory (; ; colloquially lab) is a facility that provides controlled conditions in which scientific or technological research, experiments, and measurement may be performed. Laboratories are found in a variety of settings such as schools, universities, privately owned research institutions, corporate research and testing facilities, government regulatory and forensic investigation centers, physicians' offices, clinics, hospitals, regional and national referral centers, and even occasionally personal residences. Overview The organisation and contents of laboratories are determined by the differing requirements of the specialists working within. A physics laboratory might contain a particle accelerator or vacuum chamber, while a metallurgy laboratory could have apparatus for casting or refining metals or for testing their strength. A chemist or biologist might use a wet laboratory, while a psychologist's laboratory might be a room with one-way mirrors and hidden cameras in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
