Back projection chemical shift

Fig. 9 HNCO spectra of ubiquitin. Top panels show the addition of 0°, 90°, and 30° projections of the two jointly sampled indirect dimensions at a proton chemical shift of 8.14 ppm, reconstructed using back projection reconstruction. Each projection contains 52 complex points thus the total number of complex points sampled from left to right is 52, 104, and 156. The lower panel shows MaxEnt reconstruction using the same number of complex data points, distributed randomly along the nitrogen dimension (constant time) and with an exponentially decreasing sampling density decay rate corresponding to 15 Hz in the carbon dimension. A ID trace at the position of the weakest peak present in the spectrum is shown at the top of each spectrum (indicated by a dashed line). The insets depict the sampling scheme...

Figure 9.16 and H (on C3, the front carbon in the Newman projection) experience different environments in these three conformations, as well as in every other possible conformation of 2-butanol, because of the chirality center at C2 (the back carbon in the Newman projection). In other words, the molecular landscape as viewed from one diastereotopic hydrogen will always appear different from that viewed by the other. Hence, and experience different magnetic environments and therefore should have different chemical shifts (though the difference may t>e small). They are not chemical shift equivalent. 

Inclusion of courses in reaction kinetics, process control, economics of the chemical indust, project evaluation and increased emphasis on process design. A decade of courses in transport phenomena end with a partial shift back to the unit operations. 

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