Effect of high speed pumps on the determination of gases in metals by the vacuum fusion method

Quantitative analysis of short-chain phosphates by phosphorus-31 nuclear magnetic resonance and interlaboratory comparison with infrared and chromatographic methods

“…As the basis for quantitative determination of phosphate species, phosphorus-31 NMR offers several potential advantages compared to chromatography, including (1) simultaneous observation of all phosphorus-containing species and only the phosphorus-containing species, (2) structural information which may complement or aid quantitation, (3) application to systems for which other methods do not exist or are not appropriate (e.g., degradation on column packing), and (4) quantitation with or without standards, and quantitation with an elemental as opposed to a molecular standard. In regard to the use of standards, Rabenstein and Keire point out that NMR differs from chromatographic and other spectroscopic methods in that a predetermined response factor for each compound being determined is not required.…”

Use of NMR techniques for toxic organophosphorus compound profiling

“…They monitored the active site histidine-57 proton resonances of trypsins and trypsinogens inhibited either with diisopropyl phosphorofluoridate or bovine pancreatic trypsin inhibitor in order to define the protonation states of the active site amino acids in zymogens. Steitz and Shulman [46] reviewed crystallographic and NMR spectroscopy studies on the structure and enzymatic mechanism of serine proteases, and presented some 1 H NMR, 13 C NMR, and 15 N NMR data. These nuclei are utilized in the general NMR methodology for the structural characterization of biomacromolecules, and the research field has developed a great deal in last decades.…”

“…The authors' interest for the corresponding sulfoxide and sulfone products was due to their potential toxicological relevance as bioactivation products of phosphorothiolate pesticides [65]. The authors reported 1 H, 13 C, and 31 P assignments of several intermediate products as well as the assignments of the final sulfoxide/sulfone compounds found after m-chloroperoxybenzoic acid treatment. In a subsequent study, Wu and Casida [66] represented a toxicity study of ethyl octylphosphonofluoridate and its analogues in inhibition of neuropathy target esterase [67].…”

“…The strength of NMR spectroscopy has been in characterization of the chemical structures [12], and by that giving information about the OP compound degradation processes in the environment as well as the OP compound metabolism in organisms. Because NMR is also a quantitative technique [13], it has been applied in quality control of the OP pesticides and other agrochemical products [14]. Finally, NMR is nondestructive, meaning that the sample can be analyzed without consuming it during the process like with GC-MS or LC-MS techniques, and the sample can be stored after the analysis for later studies.…”

Nuclear magnetic resonance spectrometry

“…Quantitative analysis studies by phosphorus-31 NMR (1677), as well as a general review of the applications of phosphorus-31 NMR (1678) have been presented. Phosphorous-31 NMR chemical shifts studies include complexes such as diethylphenylphosphorates (1679), phosphorus tribromide (1680), quaternary phosphonium salts (1681), coordinated tertiary phosphines (1682) and elemental phosphorus in the gas phase (1683).…”