Code: PD	Time Slot/Poster Number: 060	Session: Exotica and Beyond, Poster
Hindered Motion of Water near Hydrophobic Buckyball
Sungsool Wi; William Ducker; Justin Spano
Virginia Tech, Blacksburg, VA
Abstract
1H–13C cross polarization nuclear magnetic resonance (CPNMR) experiments show that the thin layer of liquid water around C60 is anisotropic and undergoes motion that is greatly hindered compared to motion in bulk. The water in thin layer around C60 is found to be anisotropic on a timescale of the order of milliseconds, compared to the picosecond timescales previously established for bulk water. This work provides molecular-scale evidence that a small hydrophobic particle can order surrounding liquid water molecules.

Code: PD	Time Slot/Poster Number: 061	Session: Exotica and Beyond, Poster
NMR Studies of the Dynamics of Porous Inorganic Capsules
Erhard T.K. Haupt
Department Chemistry University Hamburg, Hamburg, Germany
Abstract
The artificial cell type behaviour of porous inorganic molecular capsules of the type [[(MoVI)MoVI5O21(H2O)6]12[MoV2O4(SO4)]30]72- can be studied nicely with various types of NMR experiments, especially concerning their interaction with surrounding ingredients in solutions.

Code: PD	Time Slot/Poster Number: 062	Session: Exotica and Beyond, Poster
Theory of long-lived coherences under periodic and aperiodic multiple pulse excitation
Jamie Walls
Department of Chemistry, University of Miami, Coral Gables, FL
Abstract
Recent experiments have demonstrated that the effective T2 in dipolar coupled spin systems can be lengthened by the application of CPMG-like sequences. The theoretical explanation for the lengthening of T2, however, is still unresolved. In this work, a theory that describes the long-lived coherence under CPMG-like excitation is presented. For imperfect pi-pulses, an effective field is generated whose orientation depends on the transition frequencies between any two-spin states. For transition frequencies that are an integer multiple of one over the interpulse spacing, an effective spin-locking field is generated that leads to the observation of long-lived (or selectively spin-locked) coherences.

Code: PD	Time Slot/Poster Number: 063	Session: Exotica and Beyond, Poster
NMR (almost) Without Hamiltonians
Alex D. Bain; Bob Berno
McMaster University, Hamilton, Canada
Abstract
A method of describing NMR without calculating commutators is described. Any commutator is an operator, and any operator can be expressed as an expansion of other operators. There is, therefore, an explicit expression for any commutator. If we exploit the angular momentum properties, i.e. use spherical tensor operators, these formulae are already worked out. It turns out that the standard NMR interactions - Zemman, quadrupole, scalar and dipolar couplings - can all be expressed in terms of three simple formulae.

Code: PD	Time Slot/Poster Number: 064	Session: Exotica and Beyond, Poster
Inexpensive Portable NMR and MRI Systems Operating in kHz Range and their Applications
Igor M. Savukov; Andrei N. Matlashov; Petr L. Volegov; Vadim S. Zotev; Michelle A. Espy
LANL, Los Alamos, NM
Abstract
We would like to report results of investigation of ultra-low NMR system based on conventional pick-up coils in a wide range of frequencies (from 10 – 100 kHz). We will discuss the potential application of this system to plant research, airport security, and anatomical MRI. The system has sufficient sensitivity to detect a fraction of cc in a single scan. It has also multiple advantages of ULF NMR: portability, low cost, simplicity, safety, and others.

Code: PD	Time Slot/Poster Number: 065	Session: Exotica and Beyond, Poster
Non-invasive and Rapid Characterization of Interaction of Water with Carbon Nanotubes using Low-field TD-NMR
Supriyo Ghosh1; Xenia Tombokan1; Parameswar Hari2
1Bruker Corporations, The Woodlands, TX; 2University of Tulsa, Tulsa, OK
Abstract
Carbon nanotubes are increasingly being investigated for various novel applications, due to their unique properties. One of the interesting properties of CNT is its very high efficiency of water transport, which is attractive for nanofilters and nanosyringes for drug delivery. The evidence that transport rate exhibited by these CNTs exceed the continuum mechanics based predictions, provides motivation for fundamental study of how water interact with the CNT surfaces and thus changes its own mobility. High resolution NMR is being utilized by various groups to investigate this interaction. TD-NMR is adopted in this research to investigate the status of water inside and outside the single-walled CNTs, through a set of experiments utilizing opening and closing of CNTs, followed by continual desorption.

Code: PD	Time Slot/Poster Number: 066	Session: Exotica and Beyond, Poster
Rabi double resonance in explosives
David W Prescott; Karen Sauer
George Mason University, Chantilly, VA
Abstract
Although nuclear quadrupole resonance can be used to detect many types of explosives containing nitrogen, it suffers from a low SNR, particularly with long T1 samples. However, if the material also contains hydrogen, then a hydrogen-nitrogen resonance can be created that can improve SNR. While some of these double resonance experiments utilize a large static magnetic field to increase signal, we utilize only a small field. Further, when we model the system by using the heterogeneous dipolar Hamiltonian as a perturbation of the combined quadrupole and Zeeman Hamiltonians, we find three double-resonance conditions, involving static and rf fields. We explore how to improve the SNR with these conditions and we demonstrate a SNR improvement of 3.6 with ammonium nitrate.