@article {1094, title = {Parahydrogen-induced polarization at zero magnetic field}, journal = {The Journal of Chemical Physics}, volume = {138}, year = {2013}, month = {06/2013}, pages = {234201}, abstract = {

We use symmetry arguments and simple model systems to describe the conversion of the singlet state of parahydrogen into an oscillating sample magnetization at zero magnetic field. During an initial period of free evolution governed by the scalar-coupling Hamiltonian HJ, the singlet state is converted into scalar spin order involving spins throughout the molecule. A short dc pulse along the z axis rotates the transverse spin components of nuclear species I and S through different angles, converting a portion of the scalar order into vector order. The development of vector order can be described analytically by means of single-transition operators, and it is found to be maximal when the transverse components of I are rotated by an angle of \±π/2 relative to those of S. A period of free evolution follows the pulse, during which the vector order evolves as a set of oscillating coherences. The imaginary parts of the coherences represent spin order that is not directly detectable, while the real parts can be identified with oscillations in the z component of the molecular spin dipole. The dipole oscillations are due to a periodic exchange between Iz and Sz, which have different gyromagnetic ratios. The frequency components of the resulting spectrum are imaginary, since the pulse cannot directly induce magnetization in the sample; it is only during the evolution under HJ that the vector order present at the end of the pulse evolves into detectable magnetization. \© 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4805062]

}, doi = {doi: http://dx.doi.org/10.1063/1.4805062}, url = {http://link.aip.org/link/?JCP/138/234201\&aemail=author}, author = {Butler, Mark C. and Kervern, Gwendal and Theis, Thomas and Ledbetter, Micah P. and Ganssle, Paul J. and Blanchard, John W. and Budker, Dmitry and Pines, Alexander} } @article {253, title = {Parahydrogen-enhanced zero-field nuclear magnetic resonance}, journal = {Nature Physics}, volume = {7}, year = {2011}, note = {Nat Phys786FYTimes Cited:9Cited References Count:31}, month = {Jul}, pages = {571-575}, abstract = {

Nuclear magnetic resonance, conventionally detected in magnetic fields of several tesla, is a powerful analytical tool for the determination of molecular identity, structure and function. With the advent of prepolarization methods and detection schemes using atomic magnetometers or superconducting quantum interference devices, interest in NMR in fields comparable to the Earth\&$\#$39;s magnetic field and below (down to zero field) has been revived. Despite the use of superconducting quantum interference devices or atomic magnetometers, low-field NMR typically suffers from low sensitivity compared with conventional high-field NMR. Here we demonstrate direct detection of zero-field NMR signals generated through parahydrogen-induced polarization, enabling high-resolution NMR without the use of any magnets. The sensitivity is sufficient to observe spectra exhibiting (13)C-(1)H scalar nuclear spin-spin couplings (known as J couplings) in compounds with (13)C in natural abundance, without the need for signal averaging. The resulting spectra show distinct features that aid chemical fingerprinting.

}, keywords = {order}, isbn = {1745-2473}, doi = {Doi 10.1038/Nphys1986}, url = {://WOS:000292290000017}, author = {Theis, T. and Ganssle, P. and Kervern, G. and Knappe, S. and Kitching, J. and Ledbetter, M. P. and Budker, D. and Pines, A.} } @article {272, title = {Picomolar sensitivity MRI and photoacoustic imaging of cobalt nanoparticles}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {106}, year = {2009}, note = {P Natl Acad Sci USA420HDTimes Cited:43Cited References Count:41}, month = {Mar 17}, pages = {4085-4089}, abstract = {

Multimodality imaging based on complementary detection principles has broad clinical applications and promises to improve the accuracy of medical diagnosis. This means that a tracer particle advantageously incorporates multiple functionalities into a single delivery vehicle. In the present work, we explore a unique combination of MRI and photoacoustic tomography (PAT) to detect picomolar concentrations of nanoparticles. The nanoconstruct consists of ferromagnetic (Co) particles coated with gold (Au) for biocompatibility and a unique shape that enables optical absorption over a broad range of frequencies. The end result is a dual-modality probe useful for the detection of trace amounts of nanoparticles in biological tissues, in which MRI provides volume detection, whereas PAT performs edge detection.

}, keywords = {cancer}, isbn = {0027-8424}, doi = {Doi 10.1073/Pnas.0813019106}, url = {://WOS:000264278800008}, author = {Bouchard, L. S. and Anwar, M. S. and Liu, G. L. and Hann, B. and Xie, Z. H. and Gray, J. W. and Wang, X. D. and Pines, A. and Chen, F. F.} } @article {290, title = {Para-hydrogen-enhanced hyperpolarized gas-phase magnetic resonance imaging}, journal = {Angewandte Chemie-International Edition}, volume = {46}, year = {2007}, note = {Angew Chem Int Edit174ZPTimes Cited:28Cited References Count:37}, pages = {4064-4068}, keywords = {he-3}, isbn = {1433-7851}, doi = {Doi 10.1002/Anie.200700830}, url = {://WOS:000246981900008}, author = {Bouchard, L. S. and Kovtunov, K. V. and Burt, S. R. and Anwar, M. S. and Koptyug, I. V. and Sagdeev, R. Z. and Pines, A.} } @article {285, title = {Para-hydrogen-induced polarization in heterogeneous hydrogenation reactions}, journal = {Journal of the American Chemical Society}, volume = {129}, year = {2007}, note = {J Am Chem Soc160MRTimes Cited:36Cited References Count:45}, month = {May 2}, pages = {5580-5586}, abstract = {

We demonstrate the creation and observation of para-hydrogen-induced polarization in heterogeneous hydrogenation reactions. Wilkinson\&$\#$39;s catalyst, RhCl(PPh3)(3), supported on either modified silica gel or a polymer, is shown to hydrogenate styrene into ethylbenzene and to produce enhanced spin polarizations, observed through NMR, when the reaction was performed with H-2 gas enriched in the para spin isomer. Furthermore, gaseous phase para-hydrogenation of propylene to propane with two catalysts, the Wilkinson\&$\#$39;s catalyst supported on modified silica gel and Rh(cod)(sulfos) (cod = cycloocta-1,5-diene; sulfos = -O3S(C6H4)CH2C(CH2PPh2)(3)) supported on silica gel, demonstrates heterogeneous catalytic conversion resulting in large spin polarizations. These experiments serve as a direct verification of the mechanism of heterogeneous hydrogenation reactions involving immobilized metal complexes and can be potentially developed into a practical tool for producing catalyst-free fluids with highly polarized nuclear spins for a broad range of hyperpolarized NMR and MRI applications.

}, keywords = {alignment}, isbn = {0002-7863}, doi = {Doi 10.1021/Ja068653o}, url = {://WOS:000245946400064}, author = {Koptyug, I. V. and Kovtunov, K. V. and Burt, S. R. and Anwar, M. S. and Hilty, C. and Han, S. I. and Pines, A. and Sagdeev, R. Z.} } @article {374, title = {A porous crystalline molecular solid explored by hyperpolarized xenon}, journal = {Angewandte Chemie-International Edition}, volume = {39}, year = {2000}, note = {Angew Chem Int Edit343KUTimes Cited:116Cited References Count:38}, pages = {2695-2698}, keywords = {c-13}, isbn = {1433-7851}, doi = {Doi 10.1002/1521-3773(20000804)39:15<2695::Aid-Anie2695>3.0.Co;2-M}, url = {://WOS:000088702200008}, author = {Sozzani, P. and Comotti, A. and Simonutti, R. and Meersmann, T. and Logan, J. W. and Pines, A.} } @book {385, title = {Proc. of the Int. School of Physics, Enrico Fermi Course CXXXIX - Magnetic Resonance and Brain Funtion: Approaches from Physics}, series = {NMR and MRI of Laser-Polarized Noble Gases in Molecules}, year = {1999}, publisher = {IOS Press}, organization = {IOS Press}, chapter = {211-226}, author = {Goodson, B.M. and Kaiser, L. and Pines, A.} } @book {386, title = {Proc. of the Int. School of Physics, Enrico Fermi Course CXXXIX - Magnetic Resonance and Brain Funtion: Approaches from Physics}, series = {Lectures on Pulsed NMR}, year = {1998}, pages = {210}, publisher = {IOS Press}, organization = {IOS Press}, edition = {3rd}, chapter = {45-210}, author = {Emsley, L. and Laws, D. and Pines, A.} } @article {413, title = {P-31 to Se-77 cross polarization in beta-P4Se3}, journal = {Solid State Nuclear Magnetic Resonance}, volume = {8}, year = {1997}, note = {Solid State Nucl MagYd904Times Cited:7Cited References Count:12}, month = {Aug}, pages = {265-267}, abstract = {

Cross polarization from P-31 to Se-77 is demonstrated in beta-P4Se3. This material, an inorganic glass, is readily synthesized from the elements and serves as a convenient sample for setting the Hartmann-Hahn condition. (C) 1997 Elsevier Science B.V.

}, keywords = {f-19}, isbn = {0926-2040}, doi = {Doi 10.1016/S0926-2040(97)00012-X}, url = {://WOS:A1997YD90400008}, author = {Pietrass, T. and Seydoux, R. and Roth, R. E. and Eckert, H. and Pines, A.} } @article {467, title = {Probing Cds Nanocrystal Surfaces with Laser-Polarized Xenon}, journal = {Journal of Physical Chemistry}, volume = {98}, year = {1994}, note = {J Phys Chem-UsPh559Times Cited:32Cited References Count:29}, month = {Sep 22}, pages = {9400-9404}, abstract = {

This paper describes the application of optically pumped xenon NMR to probe the surface of semiconductor nanocrystals by physisorption at 123 K. These experiments were made possible by using highly spin ordered Xe-129, prepared by optical pumping and spin exchange of a rubidium xenon gas mixture, to increase the NMR signal strength. CdS nanocrystals were prepared by regulated growth in inverse micelles and precipitated by surface derivatization with thiophenol. Nanocrystals of 11.8, 12.8, and 23 Angstrom radii with 26\%, 63\%, and 57\% thiophenol surface coverage, respectively, were characterized. Within this sample parameter space, the Xe-129 spectra, recorded at varying xenon coverages, depended strongly on thiophenol surface coverage but were not sensitive to the crystallite size. In addition, the nanocrystals with low thiophenol coverage yielded a xenon line shape consisting of two components, interpreted as xenon signals arising from distinct surface domains. These domains are presumably formed by the aggregation of thiophenol molecules on the nanocrystal surface when the thiophenol coverage is incomplete, a model which is consistent with existing X-ray photoelectron spectroscopy and liquid state H-1 NMR data.

}, keywords = {resonance}, isbn = {0022-3654}, doi = {Doi 10.1021/J100089a008}, url = {://WOS:A1994PH55900008}, author = {Bowers, C. R. and Pietrass, T. and Barash, E. and Pines, A. and Grubbs, R. K. and Alivisatos, A. P.} } @book {481, title = {Proceedings of the International School of Physics Enrico Fermi, Course CXXIII 1992}, series = {Lectures in Pulsed NMR}, year = {1994}, publisher = {World Scientific}, organization = {World Scientific}, edition = {2nd}, chapter = {123-266}, author = {Emsley, L. and Pines, A.} } @article {478, title = {Pure-Absorption-Mode Lineshapes and Sensitivity in 2-Dimensional Dynamic-Angle Spinning Nmr}, journal = {Journal of Magnetic Resonance Series A}, volume = {103}, year = {1993}, note = {J Magn Reson Ser ALj625Times Cited:98Cited References Count:20}, month = {Jun 1}, pages = {72-81}, keywords = {nuclei}, isbn = {1064-1858}, doi = {Doi 10.1006/Jmra.1993.1132}, url = {://WOS:A1993LJ62500010}, author = {Grandinetti, P. J. and Baltisberger, J. H. and Llor, A. and Lee, Y. K. and Werner, U. and Eastman, M. A. and Pines, A.} } @article {495, title = {Pulsed Fourier-Transform Nqr of N-14 with a Dc Squid}, journal = {Physical Review Letters}, volume = {69}, year = {1992}, note = {Phys Rev LettJe754Times Cited:23Cited References Count:27}, month = {Jul 27}, pages = {684-687}, abstract = {

The zero-field free induction decay of solid ammonium perchlorate at 1.5 K has been directly detected with a dc superconducting quantum interference device. The Fourier-transform spectrum consists of three sharp lines at 17.4, 38.8, and 56.2 kHz arising from pure N-14 nucLear quadrupole resonance transitions. The absence of splittings and resonance transitions from dipolar-coupled proton spins is attributed to reorientation of the ammonium groups by quantum tunneling in combination with motional averaging in the three proton levels characterized by the irreducible representation T. The measured N-14 spin-spin relaxation time is 22+/-2 ms and the spin-lattice relaxation time is 63+/-6 ms.

}, keywords = {nh4clo4}, isbn = {0031-9007}, doi = {Doi 10.1103/Physrevlett.69.684}, url = {://WOS:A1992JE75400034}, author = {Hurlimann, M. D. and Pennington, C. H. and Fan, N. Q. and Clarke, J. and Pines, A. and Hahn, E. L.} } @article {505, title = {Pure-Absorption-Phase Dynamic-Angle Spinning}, journal = {Journal of Magnetic Resonance}, volume = {92}, year = {1991}, note = {J Magn ResonFj100Times Cited:30Cited References Count:15}, month = {May}, pages = {620-627}, keywords = {nuclei}, isbn = {0022-2364}, doi = {Doi 10.1016/0022-2364(91)90359-2}, url = {://WOS:A1991FJ10000018}, author = {Mueller, K. T. and Wooten, E. W. and Pines, A.} } @article {561, title = {Phase-Incremented Multiple-Quantum Nmr Experiments}, journal = {Journal of Magnetic Resonance}, volume = {76}, year = {1988}, note = {J Magn ResonL9552Times Cited:49Cited References Count:17}, month = {Jan}, pages = {149-154}, isbn = {0022-2364}, doi = {Doi 10.1016/0022-2364(88)90209-0}, url = {://WOS:A1988L955200015}, author = {Shykind, D. N. and Baum, J. and Liu, S. B. and Pines, A.} } @article {569, title = {Probing Metal Cluster Formation in Nay Zeolite by Xe-129 Nmr}, journal = {Journal of the American Chemical Society}, volume = {110}, year = {1988}, note = {J Am Chem SocP0739Times Cited:33Cited References Count:18}, month = {Jun 22}, pages = {4465-4467}, isbn = {0002-7863}, doi = {Doi 10.1021/Ja00221a086}, url = {://WOS:A1988P073900086}, author = {Chmelka, B. F. and Ryoo, R. and Liu, S. B. and Demenorval, L. C. and Radke, C. J. and Petersen, E. E. and Pines, A.} } @article {596, title = {Pake Patterns from Zero to High-Field}, journal = {Journal of Magnetic Resonance}, volume = {74}, year = {1987}, note = {J Magn ResonK2008Times Cited:2Cited References Count:17}, month = {Sep}, pages = {381-385}, isbn = {0022-2364}, doi = {Doi 10.1016/0022-2364(87)90349-0}, url = {://WOS:A1987K200800016}, author = {Bielecki, A. and Pines, A.} } @article {585, title = {Principles and Applications of Multiple-Quantum Nmr}, journal = {Advances in Chemical Physics}, volume = {66}, year = {1987}, note = {Adv Chem PhysF9398Times Cited:113Cited References Count:286}, pages = {1-152}, isbn = {0065-2385}, url = {://WOS:A1987F939800001}, author = {Munowitz, M. and Pines, A.} } @article {666, title = {Proton-Enhanced Deuterium Nmr in Rotating Solids}, journal = {Chemical Physics Letters}, volume = {76}, year = {1980}, note = {Chem Phys LettKt859Times Cited:10Cited References Count:22}, pages = {149-154}, isbn = {0009-2614}, doi = {Doi 10.1016/0009-2614(80)80625-7}, url = {://WOS:A1980KT85900034}, author = {Muller, L. and Eckman, R. and Pines, A.} } @article {707, title = {Proton-Enhanced Nmr of Dilute Spins in Solids}, journal = {Journal of Chemical Physics}, volume = {59}, year = {1973}, note = {J Chem PhysQ3293Times Cited:2144Cited References Count:119}, pages = {569-590}, isbn = {0021-9606}, doi = {Doi 10.1063/1.1680061}, url = {://WOS:A1973Q329300001}, author = {Pines, A. and Gibby, M. G. and Waugh, J. S.} } @article {708, title = {Pulsed Spin Decoupling in Nuclear Magnetic-Resonance}, journal = {Journal of the American Chemical Society}, volume = {95}, year = {1973}, note = {J Am Chem SocQ0006Times Cited:7Cited References Count:5}, pages = {4437-4438}, isbn = {0002-7863}, doi = {Doi 10.1021/Ja00794a059}, url = {://WOS:A1973Q000600060}, author = {Pines, A. and Ellett, J. D.} } @article {719, title = {P-31 Chemical Shielding Anisotropy in Solids - Single-Crystal and Powder Studies at 99.4 Mhz}, journal = {Journal of Chemical Physics}, volume = {56}, year = {1972}, note = {J Chem PhysL3043Times Cited:33Cited References Count:21}, pages = {991-\&}, isbn = {0021-9606}, doi = {Doi 10.1063/1.1677259}, url = {://WOS:A1972L304300043}, author = {Gibby, M. G. and Waugh, J. S. and Pines, A. and Rhim, W. K.} } @proceedings {714, title = {Proton-enhance NMR of dilute spins in solids, proceedings of the congress ampere}, journal = {The Congress Ampere}, year = {1972}, pages = {11-17}, publisher = {North Holland Publishers}, address = {Turku, Finland}, author = {Waugh, J.S. and Gibby, M.G. and Kaplan, S. and Pines, A.} } @article {716, title = {Proton-Enhanced Nuclear Induction Spectroscopy C-13 Chemical Shielding Anisotropy in Some Organic Solids}, journal = {Chemical Physics Letters}, volume = {15}, year = {1972}, note = {Chem Phys LettN5315Times Cited:290Cited References Count:10}, pages = {373-\&}, isbn = {0009-2614}, doi = {Doi 10.1016/0009-2614(72)80191-X}, url = {://WOS:A1972N531500014}, author = {Pines, A. and Waugh, J. S. and Gibby, M. G.} } @article {715, title = {Proton-Enhanced Nuclear Induction Spectroscopy - Method for High-Resolution Nmr of Dilute Spins in Solids}, journal = {Journal of Chemical Physics}, volume = {56}, year = {1972}, note = {J Chem PhysL5803Times Cited:520Cited References Count:10}, pages = {1776-\&}, isbn = {0021-9606}, doi = {Doi 10.1063/1.1677439}, url = {://WOS:A1972L580300054}, author = {Pines, A. and Waugh, J. S. and Gibby, M. G.} } @article {721, title = {Proton-Enhanced Nuclear Induction Spectroscopy - Silicon-29 Chemical Shielding Anisotropy in Some Organosilicon Compounds}, journal = {Journal of the American Chemical Society}, volume = {94}, year = {1972}, note = {J Am Chem SocN2839Times Cited:31Cited References Count:5}, pages = {6231-\&}, isbn = {0002-7863}, doi = {Doi 10.1021/Ja00772a071}, url = {://WOS:A1972N283900071}, author = {Gibby, M. G. and Pines, A. and Waugh, J. S.} }