1H NMR Analysis of Hard Apple Cider

There have been quite a lot of NMR studies centered around apple cider (non-alcoholic) and apple cider vinegar. However a search of the literature turns up no reference for NMR analysis of hard apple cider. This effort was undertaken to analyse the alcohol content of the ciders and to determine the malic and acetic acid content. Ciders were produced by Dr Tim McMahon of Orange Community College, NY....for his own consumption. Below are the NMR spectra obtained by regular 1H acquisition and with BINOM solvent suppression. Data was obtained on our Varian 300 MHz spectrometer. Samples were prepared by degassing followed by addition of 1 drop of D2O as lock solvent.

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Micro-ESR Spectrometry of Crude Oils

Process NMR Associates, LLC (Danbury CT) and Active Spectrum, Inc (San Carlos CA) are collaborating in the application of micro-ESR technology to petroleum applications. The initial work has focussed on crude oils but will soon be expanded to residues and cracker feedstocks. Five samples of crude oil were tested by Micro-ESR spectrometry. The samples were: 1. Vasconia, Magdalena Basin, Columbia (V=39 ppm) 2. Merey, Eastern Venezuela Basin, Venezuela (V=303 ppm) 3. Oriente, Oriente Basin, Ecuador (V=65 ppm) 4. Qua Iboe, Agbada Formation, Niger Delta (V=2 ppm) 5. Basrah Light, Zubair Zone, Iraq (V=29 ppm) The following spectra were observed: Figure 1: Micro-ESR Spectra of Crude Oil The central peak is a combination of a persistent carbon-centered organic radical (g = 2.003) found in asphaltenes, and a vanadyl (VO2+) peak. The additional smaller peaks are associated with vanadyl only. For producers, the technique could be used to rapidly measure asphaltene concentration on-line. The spin density of the organic radical is a function of the maturity of the oil and will of course vary between deposits. Notwithstanding, rapid electronic measurement of asphaltenes remains a topic of great interest. Similar techniques have also been used to assess the quality of coals. For refiners,…

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