A method based on rotational-echo double-resonance (REDOR) NMR is proposed to measure H–N bond lengths under magic-angle-spinning. Protons are selectively polarized and evolve under the frequency-switched Lee– Goldburg (FSLG) homonuclear decoupling, while two N p pulses are applied to restore H–N dipolar interactions. Such a method relies on the H–N dipolar couplings and requires no knowledge o...

An improved version of the three-dimensional HCCH-COSY NMR experiment is described that correlates the resonances of geminal and vicinal proton pairs with the chemical shift of the 13C nucleus attached to one of the protons. The experiment uses constant-time evolution of transverse 13C magnetization which optimizes transfer of magnetization and thus improves the sensitivity of the experiment ov...

In this study, B12N12 Nano ring has been selected because it consist of four 6-side rings and polar bonds B-N which in comparison with non-polar bonds C-C, is more suitable for the study of the absorption of other compounds. So reactivity and stability of Benzene alone and in the presence B12N12 nano ring field checked. To determine the non-bonded interaction energies between Benzene and B12N12...

The purpose of this study was to evaluate the presence of chemical-shift artifacts on cranial MR and to illustrate the interrelationship among chemical-shift artifacts, variable acquisition parameters, and field strength. Measurements of chemical-shift artifacts were performed on scans obtained from a volunteer imaged in a 1.5-T General Electric system at bandwidths of 8, 16, and 32 kHz, using ...

The public archives containing protein information in the form of NMR chemical shift data at the BioMagResBank (BMRB) and of 3D structure coordinates at the Protein Data Bank are continuously expanding. The quality of the data contained in these archives, however, varies. The main issue for chemical shift values is that they are determined relative to a reference frequency. When this reference ...

Recoil-free emission of 14.37 keV lines by iron atoms undergoing radioactive decay can be exploited in high-resolution Mössbauer spectroscopy thanks to the long lifetime of the excited state. This experiment determined the natural energy width of the Mössbauer 14.37 keV line to be (1.36 ± 0.24)· 10−12 keV, giving a relative width of around 10−13. Another application of this experiment was in ch...

A method to study event–by–event fluctuations of the " chemical " (particle type) composition of the final state of high energy collisions is proposed.