Associate Professor Lomax's research interests is cultural heritage science and art conservation chemistry. He has collaborations with the National Gallery of Art, Washington with Dr. Suzanne Q. Lomax, the Naval Academy Museum and Naval History & Heritage Command.
The emphasis of Prof. Lomax’s research is guiding midshipmen exploration of micro-analytical vibrational spectroscopy and mass spectrometry of colorants. That is a lot of words, so let’s take them a little at a time.
“Guiding Midshipmen”: Prof. Lomax is proud to have mentored 35 midshipmen over the past 33 years. His current work was suggested/inspired by a midshipman, Amadeo DeLuca-Westrate (Class of 2012) and has resulted in students going to national meetings include, among others the major papers below.
“Historical azo pigments: Synthesis and characterization”, Lomax, Suzanne Q.;, Lomax, Joseph F.; Graham, Trevor K.; Moore, Thomas J. T., Journal of Cultural Heritage, 35, January–February 2019, pp. 218-224.
“Synthesis of Historical Azo Pigments: The Challenge and Opportunity of the Nearly Forgotten” Lomax, Joseph F.; Lomax, Suzanne Q.; Moore, Thomas J. T. MRS Advances 2017, 2(37-38), 2007-2019.
“The use of Raman microscopy and laser desorption ionization mass spectrometry in the examination of synthetic organic pigments in modern works of art” Lomax, Suzanne Quillen; Lomax, Joseph Francis; De Luca-Westrate, Amadeo J. Raman Spectros. 2014, 45(6), 448-455.
“Micro-analytical”: Sample size in art conservation needs to be exceptionally small. A typical sample will be unnoticed by the eye and 1/10th the size of the period at the end of this sentence. Thus, techniques must be chosen so that will be either non-destructive or they need miniscule sample size.
“Vibrational spectroscopy”: Spectroscopy is the interaction of light with matter. Bonds in matter are connections of atoms with specific masses and bond strength. These vibrate like a spring, and the molecule will vibrate depending upon the atoms and type of bonds. The two techniques used are based on absorbance of infrared (IR) light and scattering of visible light (Raman spectroscopy named after a physicist). In general, a particular bond type, like a C=O will vibrate at a particular energy range, and thus the vibration is diagnostic. In addition, our instruments we have enough resolution to subtlety distinguish differences in very similar molecules.
“Mass spectrometry”: Mass Spectrometry (ms) takes a molecule, ionizes it, and sends it through a magnetic field than detects the amount of charge. Relying on the mass of the molecule for identification, again, is very diagnostic, but using completely different characteristics from vibrational spectroscopy. Thus the two are complementary editors to the identity of the molecule. So, if both point to the same molecular structure, deciding its identity is easier and more reliable.
The ”colorants” we investigate are synthetic organic pigments (insoluble) or dyes(soluble). Historical pigments are ones that were in and then fell out of manufacture, thus they have a history. Most of these were out of production before microanalytical techniques were developed, and thus did not have vibrational or mass spectrometic data on them. Having identified historical pigments in art samples, we did a systematic project where we synthesized and analyzed a historical pigments. Recently, we have turned our attention to commercial dyes which are mixtures. In addition to the above techniques, we are using chromatographic techniques to separate and identify dyes mixtures. We hope that this work will inform cultural heritage science as well as forensic science. This work is being done in collaboration with Prof. Copper in our Chemistry Department.
If you have a rooting interest in this work, or you have any questions, please contact me.
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