Chemical Structure / July 16, 2018 / Isabelle Vinson
Most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. The sample is placed in a magnetic field and the NMR signal is produced by excitation of the nuclei sample with radio waves into nuclear magnetic resonance, which is detected with sensitive radio receivers. The intramolecular magnetic field around an atom in a molecule changes the resonance frequency, thus giving access to details of the electronic structure of a molecule and its individual functional groups. As the fields are unique or highly characteristic to individual compounds, in modern organic chemistry practice, NMR spectroscopy is the definitive method to identify monomolecular organic compounds. Similarly, biochemists use NMR to identify proteins and other complex molecules.
Barium chloride has several important functions, but one very familiar to chemists is the role of "sulfate detective." Sulfate, SO4-2 is a negatively charged chemical unit consisting of a sulfur atom bonded to four oxygen atoms. These negatively charged units are known as negatively charged ions, or anions.
Melamine use as non-protein nitrogen (NPN) for cattle was described in a 1958 patent. In 1978, however, a study concluded that melamine "may not be an acceptable non-protein N source for ruminants" because its hydrolysis in cattle is slower and less complete than other nitrogen sources such as cottonseed meal and urea.
Benzyl chloride is used as a chemical intermediate in the manufacture of certain dyes and pharmaceutical products and as a photographic developer. The acute (short-term) effects of benzyl chloride from inhalation exposure in humans consist of severe irritation of the upper respiratory tract, skin, eyes, and mucous membranes, and lung damage along with pulmonary edema (fluid in lungs).
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