Introduction
Preliminary
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Present Life
Past Life
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Experimental Design Nuclear Magnetic Resonance Spectroscopy The nuclei of all elements carry a charge. When the spins of the protons and neutrons comprising these nuclei are not paired, the overall spin of the charged nucleus generates a magnetic dipole along the spin axis. The absorption of frequencies is plotted and a NMR spectrum is produced which can be analyzed to give the exact molecular structure of the sample. Some of the functions of NMR Spectroscopy include (http://www.ch.ic.ac.uk/local/organic/nmr_scope.html):
In addition to immediate analysis of organic compounds, NMR spectroscopy is able to perform time-lapsed real-time molecular determination, reaction rates, etc. that is useful to see how a sample changes over time.
A high frequency (strong magnet) is necessary to achieve a high level of detail and precision, yet the higher the frequency, the larger and more cumbersome the magnet. Something along the order of 250 MHz. is acceptable for our mission assuming the compounds we look at won’t be super-complex. This strength is more than adequate for 90% of common molecules. A Fourier-Transfer (FT) component is absolutely necessary for NMR spectroscopy. It makes all of the preliminary analysis automated and significantly speeds up any sort of computation. A supply of helium needed to cool the magnet and the probe is also required. Picture of 500 MHz. system (significantly larger than 250 MHz.) (http://www.eecs.uic.edu/~gary/NMR/minNMR/):
The NMR Spectrometer, due to its size and relative difficulty in surface transportation, will be located in the habitat.
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Copyright © 2000 Massachusetts Institute of Technology
Comments and questions to mission2004-students@mit.edu Last updated: 10 December, 2000 |