Spelling suggestions: "subject:"buclear spin"" "subject:"anuclear spin""
101 |
New techniques in nuclear magnetic resonanceLevitt, Malcolm H. January 1981 (has links)
The effect of short, strong radiofrequency pulses on the nuclear spin system is examined. Providing the durations of the pulses are short with respect to coupling constants within the spin system, they may be described by simple rotation operators which are exponential functions of the angular momentum operators. Operator algebra can be used to define the interaction of such pulses with the spin system, and the mutual interaction of a sequence of pulses. The case of a simple coupled spin system is examined in detail and it is found that a vector model can be used to describe the motion of the expectation values of the observables. This model also allows treatment of such 'non-classical 1 effects as coherence transfer and multiple-quantum coherence. The proposal is also made that certain types of pulse imperfection may be compensated by using specially constructed sequences of small numbers of pulses, which are termed 'composite pulses'. Their compensatory action is illustrated by computer simulation, and by experimental results. In the case of certain symmetrical composite pulses, operator algebra can be used to understand their overall effect in the presence of pulse imperfections, suggesting their use in such critical applications as multiple spin echo trains. Another class of symmetrical composite pulses provides rotations by arbitrary angles around the z-axis of the rotating reference frame, and is expected to be of use in multiple-quantum spectroscopy.
|
102 |
Magnetic susceptibility observation of a spin-reorientation transition in Fe/2 ML Ni(111)/W(110) films.Arnold, C. S. January 1997 (has links)
Thesis (Ph.D.) -- McMaster University, 1997. / Includes bibliographical references. Also available via World Wide Web.
|
103 |
A torsion balance search for spin-coupled forces /Cramer, Claire E., January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (p. 118-122).
|
104 |
Applications of effective field theories to the many-body nuclear problem and frustrated spin chainsFelline, Cosimo. Piekarewicz, Jorge. January 2004 (has links)
Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Jorge Piekarewicz, Florida State University, College of Arts and Sciences, Dept. of Physics. Title and description from dissertation home page (Jan. 19, 2005). Includes bibliographical references.
|
105 |
Highly deformed rotational bands and normal deformed high spin structures in ¹⁷¹HF and ¹⁷²HFZhang, Yanci, January 2008 (has links)
Thesis (Ph.D.)--Mississippi State University. Department of Physics and Astronomy. / Title from title screen. Includes bibliographical references.
|
106 |
High-spin triaxial strongly deformed structures and quasiparticle alignments in 168HfYadav, Ram Babu, January 2009 (has links)
Thesis (Ph.D.)--Mississippi State University. Department of Physics & Astronomy. / Title from title screen. Includes bibliographical references.
|
107 |
Spin and charge transport through carbon based systemsJung, Suyong, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
|
108 |
Spin state detection and manipulation and parity violation in a single trapped ion /Schacht, Michael, January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (p. 376).
|
109 |
SPECTROSCOPIC STUDIES OF NUCLEAR SPINS POLARIZED VIA SPIN EXCHANGE OPTICAL PUMPING AND DYNAMIC COUPLING IN CRYPTOPHANE HOST-GUEST COMPLEXESNikolaou, Panayiotis 01 December 2010 (has links)
NMR is a powerful analytical spectroscopic tool used to perform detailed studies of structure and dynamics of molecules in solution. However, despite NMR's excellent spectral sensitivity, most NMR methods suffer from low detection sensitivity. This low detection sensitivity results largely from extremely small (Boltzmann) nuclear spin polarization at thermal equilibrium--in even the strongest of magnets. This dissertation focuses on selected research areas that maybe used to combat the limitations presented by NMR and measure weak spectral responses with atomic-scale precision. In particular, these methods involve the use of laser-polarized xenon, liquid crystals, and polarization transfer (cross-polarization) techniques to enhance NMR sensitivity and/or measure weak interactions. The potential use of these tools to study host-guest interactions is of particular interest. In certain systems the sensitivity problem of conventional NMR/MRI can be overcome by applying optical pumping (OP) methods to enhance nuclear spin polarization. For instance, OP of noble gases (such as xenon) is employed to dramatically increase their nuclear spin polarization by transferring angular momentum of laser light to electronic and then nuclear spins. Next, cryptophane complexes are ideal choices for fundamental studies of prototypical host-guest interactions. Of general interest when studying host-guest interactions is how (1) physical confinement at the nanoscale and (2) interactions between guest and host may affect the properties, dynamics, interactions, and/or reactivity of a trapped molecule and the host/guest complex as a whole. As a more specific example, we are interested in probing host-guest dynamic coupling, which refers to the relative motion of the guest within the host, determined by the relative sizes and geometries--as well as the interactions involved. With the development of new NMR methods and techniques, we hope to gain insight into mechanisms that underlie complex formation by probing the structures, dynamics and energetic contributions involved in ligand binding, where molecular contributions such as: orientational and motional freedom of the guest; and structure, dynamics, and ordering of the host can influence the behavior of inclusion complexes.
|
110 |
Cross Correlation Studies In Relaxation Of Coupled Spins In NMRKumar, P 12 1900 (has links) (PDF)
No description available.
|
Page generated in 0.0433 seconds