Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 26 for “"spin exchange"”.
-
Clinical-Scale Hyperpolarization of 129Xe and 131Xe via Stopped-Flow Spin Exchange Optical Pumping
The fundamental physics of spin-exchange optical pumping (SEOP) has been explained in detail by many brilliant scientists since its discovery in the 50’s and 60’s. Although some interactions remain only tenuously understood, mathematical relationships have been mapped across many trajectories with …
-
SPECTROSCOPIC STUDIES OF NUCLEAR SPINS POLARIZED VIA SPIN EXCHANGE OPTICAL PUMPING AND DYNAMIC COUPLING IN CRYPTOPHANE HOST-GUEST COMPLEXES
… 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 …
-
Exploration of Alkyne-bridged Multi[(Porphinato)metal] Oligomers for Charge Transport Applications and Spin-Spin Exchange Coupling Properties Using Synthetic, Spectroscopic, Potentiometric, and Magnetic Resonance Methods
… device components. The emerging of molecular spintronics, which exploits the spin-dependent charge transport through organic materials, further demonstrate the promising future of molecular electronics. This dissertation describes the charge transport and spin-spin electronic coupling …
-
Using High-Powered, Frequency-Narrowed Lasers For Rb/129Xe and Cs/129Xe Spin-Exchange Optical Pumping To Achieve Improved Production of Highly Spin-Polarized Xenon For Use In Magnetic Resonance Applications
… minute nuclear magnetic moments and low nuclear spin polarization levels at thermal equilibrium (~10-5 to 10-6), and thus necessitates the use of relatively large sample volumes. One way to overcome this low detection sensitivity is to introduce a species with highly non-equilibrium nuclear spin …
-
ΚΒΑΝΤΟΧΗΜΙΚΗ ΚΑΙ ΠΕΙΡΑΜΑΤΙΚΗ ΜΕΛΕΤΗ ΤΗΣ ΔΟΜΗΣ ΚΑΙ ΤΩΝ ΦΑΙΝΟΜΕΝΩΝ ΥΠΕΡΑΝΤΑΛΛΑΓΗΣΝΕΩΝ D9 ΜΑΓΝΗΤΙΚΩΝ ΣΥΣΤΗΜΑΤΩΝ ΤΟΥ ΦΘΑΛΙΚΟΥ ΚΑΙ ΙΣΟΦΘΑΛΙΚΟΥ ΟΞΕΟΣ
… STRUCTURE ALONG WITH A VERIFICATION OF THE SPIN EXCHANGE PHENOMENA, OCCURING IN TEN NEW BIMETALLIC CU(II), BRIDGED BY PHTHALIC, L AS TERMINAL LIGANDS, OF THE GENERAL FORMULA CU2(M-PHTAHA)L2CC104)2, WAS ATTEMPTED. THE COMPLEXES WERE CHARACTERIZED BYELEMENTAL ANALYSIS, MAGNETIC SUSCEPTIBILITY …
-
Investigation of Frustrated Quasi-One-Dimensional Quantum Spin-Chain Materials
… configuration) quasi-one-dimensional quantum spin-chain compounds. Both compounds crystallize with tetragonal structures containing edge sharing CuO6 octahedra chains which experience Jahn-Teller distortions. The basal planes of the octahedra link together to form CuO2 ribbon-chains which …
-
Complex Phase Behavior of Exotic Oxides: Optical Spectroscopy Studies
… 2O7, from which we could estimate the in-plane spin-spin exchange coupling constant J∥. Importantly, we found that Ca3Ru2O7 does not exhibit strong in-plane magnetic correlations above TN.
-
Electron impact excitation of 2p states in atomic hydrogen
… P+ from unity is indicative of the importance of spin exchange during the collision. A new Lyman- polarisation analyser, that permits independent rotation of a retarder and a linear polariser, was developed for this work. A novel approach to the analysis of data from electron-photon coincidence …
-
Investigation of triphenylene-based radical-containing ligand bridges in mediating electronic spin coupling and sensing chemical analytes
… magnetic material, as they mediate strong spin exchange coupling between paramagnetic metals, and have potential for maintaining coherence at room temperature. In this thesis, the author explores ligand-mediated spin coupling and quantum properties of the tritopic radical bridge HXTP (HXTP …
-
Integration and characterization of a control and signal processing system for a SERF magnetometer array
… performance characteristics. In particular, spin exchange relaxation free (SERF) magnetometers have demonstrated ultimate flux density measurement sensitivities of 10-" Tesla/Hz"', with projected fundamental sensitivity limits orders of magnitude lower. In this thesis, I describe the …
-
Proton-Deuteron Elastic Scattering and Three-Nucleon Forces
The spin observables Ay, iT11, and Cy,y in proton-deuteron elastic scattering were measured over the angular range 65° < ϴcm < 115° at a proton energy Tlab = 197 MeV. These data were acquired with a polarized proton beam and an internal vector-polarized deuteron gas target at the Indiana University …
-
Proton -Deuteron Elastic Scattering and Three -Nucleon Forces
The spin observables Ay, iT 11, and Cy,y in proton-deuteron elastic scattering were measured over the angular range 65° < theta cm < 115° at a proton energy Tlab = 197 MeV. These data were acquired with a polarized proton beam and an internal vector-polarized deuteron gas target at the …
-
Quantification of Myocardial Perfusion Based on Signal Intensity of Flow Sensitized MRI
… of measuring cardiac perfusion by arterial spin labeling, the relative difference in the apparent T1 relaxation times in response to selective and non-selective inversion of blood entering the region of interest is related to perfusion via a two-compartment tissue model. But accurate …
-
Controlling Triplet Excitons in Organic Semiconductors with Lanthanide-Doped Nanoparticles
… to control triplets, such as heavy-metal-induced spin-orbit coupling (SOC) or engineering the singlet–triplet energy splitting, impose significant design constraints on OSCs. This thesis explores a new approach to molecular triplet exciton control by combining OSCs with lanthanide-doped …
-
A precision measurement of the transverse asymmetry AT̳' from quasi-elastic ³sHe [right arrow] (e [right arrow], e') process and the neutron magnetic form factor Gn̳m̳ at low Q²
… 0.6 (GeV/c)2 were obtained using a high-pressure spin-exchange optically-pumped polarized 3He gas target with an average polarization of 30%, a longitudinally polarized e- beam, and two High Resolution Spectrometers: HRSe and HRSh. HRSe was employed to detect scattered electrons from the …
-
Precision measurement of the spin-dependent asymmetry in the threshold region of quasielastic ³He [right arrow] (e [right arrow], e)Ì
The first precision measurement of the spin-dependent asymmetry in the threshold region of 3He(e, e') was carried out in Hall A at the Jefferson Laboratory, using a longitudinally polarized continuous wave electron beam incident on a high-pressure polarized 3He gas target. The polarized electron …
-
The Influence of Inner-Sphere Reorganization on Rates of Interfacial Electron Transfer in Transition Metal-Based Redox Electrolytes
… seek to employ redox electrolytes that undergo a spin-exchange reaction induced by electron transfer. This event, known as charge transfer-induced spin crossover (CTISC), significantly increases the reorganization energy associated with electronic recombination, producing long-lived CSSs and …
-
Hyperpolarized xenon-129 production and applications
… quantities of highly polarized 129Xe. High Rb-Xe spin-exchange rates through long-lived van de Waals molecules at low total pressure, implemented in a novel counterflow polarizer design, resulted in xenon polarization as high as 50% for 1.2 liters/hour, with a maximum of 64% for 0.3 l/h. We …
-
Some metal complexes of dihydroxycyclobutenedione
… vanadium(III) squarate complex suggest some spin coupling between metal atoms. The reduced magnetic moment of 5.08 B.M. at room temperature for iron(III) squarate dihydrate, 5.9 B.M. is normal for a d⁵ metal complex, and the temperature dependence study of the magnetic susceptibility indicate …
Page 1 of 2