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Yeast need a reliable source of nitrogen in forms that they can assimilate in order to successfully complete fermentation. Yeast assimilable nitrogen or YAN is the combination of free amino nitrogen (FAN), ammonia (NH 3) and ammonium (NH 4 +) that is available for a yeast, e.g. the wine yeast Saccharomyces cerevisiae, to use during fermentation.
Archaeological materials, such as bone, organic residues, hair, or sea shells, can serve as substrates for isotopic analysis. Carbon, nitrogen and zinc isotope ratios are used to investigate the diets of past people; these isotopic systems can be used with others, such as strontium or oxygen, to answer questions about population movements and cultural interactions, such as trade.
However, the large-scale implementation of ammonia synthesis via the Haber process became a serious competitor to the very energy-intensive Frank–Caro process. As urea (formed via the Haber–Bosch process) was significantly more nitrogen-rich (46% nitrogen compared to ca. 20%), cheaper, and faster acting, the role of calcium cyanamide was ...
To simplify, two components have an energy focus term, when arranged properly, the energy term cancels out and ions with the same mass/charge ratio focus at the same point in space. It is important to note, double-focusing does not reduce the kinetic energy distribution and different kinetic energies are not filtered or homogenized.
Nitrogen assimilation is the formation of organic nitrogen compounds like amino acids from inorganic nitrogen compounds present in the environment. Organisms like plants, fungi and certain bacteria that can fix nitrogen gas (N 2) depend on the ability to assimilate nitrate or ammonia for their needs. Other organisms, like animals, depend ...
Nitrogen-15 is frequently used in NMR (Nitrogen-15 NMR spectroscopy). Unlike the more abundant nitrogen-14, which has an integer nuclear spin and thus a quadrupole moment, 15 N has a fractional nuclear spin of one-half, which offers advantages for NMR such as narrower line width. Nitrogen-15 tracing is a technique used to study the nitrogen cycle.
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A CHN analyzer (also known as a carbon hydrogen and nitrogen analyzer) is a scientific instrument which is used to measure carbon, hydrogen and nitrogen elemental concentrations in a given sample with accuracy and precision. [2] Sample sizes are most often just a few milligrams, but may differ depending on system.