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Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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1

Nuclear Magnetic Resonance Laboratory  

Science Conference Proceedings (OSTI)

Nuclear Magnetic Resonance Laboratory. ... A 600 MHz Nuclear Magnetic Resonance Spectrometer. Analytical Data Compilation Reference Materials. ...

2012-10-01T23:59:59.000Z

2

Nuclear magnetic resonance contrast agents  

DOE Patents (OSTI)

This invention relates to the field of nuclear magnetic resonance imaging and nuclear magnetic resonance spectroscopy, also known simply as magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). MRI and MRS are particularly useful in medical research and diagnosis. MRI may be used in addition to x-ray imaging. This invention concerns a family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 2 figs.

Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

1989-01-24T23:59:59.000Z

3

Nuclear magnetic resonance contrast agents  

DOE Patents (OSTI)

A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC.sub.16 H.sub.14 N.sub.6. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques.

Smith, Paul H. (Los Alamos, NM); Brainard, James R. (Los Alamos, NM); Jarvinen, Gordon D. (Los Alamos, NM); Ryan, Robert R. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

4

Nuclear magnetic resonance contrast agents  

DOE Patents (OSTI)

A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.

Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

1997-12-30T23:59:59.000Z

5

Plutonium less mysterious with nuclear magnetic resonance  

NLE Websites -- All DOE Office Websites (Extended Search)

Plutonium less mysterious with nuclear magnetic resonance Plutonium less mysterious with nuclear magnetic resonance Plutonium less mysterious with nuclear magnetic resonance For more than 50 years, chemists and physicists have been searching for the plutonium-239 magnetic resonance signal. May 21, 2012 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

6

Novel nuclear magnetic resonance techniques for studying biological molecules  

E-Print Network (OSTI)

parameters by solid-state nuclear magnetic resonance." J.and R. V. Pound. "Nuclear audiofrequency spectroscopy byresonant heating of the nuclear spin system." Phys. Rev. ,

Laws, David D.

2010-01-01T23:59:59.000Z

7

Nuclear Magnetic Resonance: Portable and integrated Lead: P. Poulichet.  

E-Print Network (OSTI)

Nuclear Magnetic Resonance: Portable and integrated Lead: P. Poulichet. Permanent members: L. Rousseau, A. Fakri. Associated researchers: C. Delabie, A. Exertier. Portable Nuclear Magnetic Resonance : our work in the field of nuclear magneto resonance is focused on the design and the realization

Baudoin, Geneviève

8

Nuclear magnetic resonance offers new insights into Pu 239  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear magnetic resonance offers new insights into Pu 239 Nuclear magnetic resonance offers new insights into Pu 239 Nuclear magnetic resonance offers new insights into Pu 239 Fingerprint of element found by LANL/Japanese team. May 29, 2012 How would the detonation of a nuclear energy source afffect an incoming asteroid? Georgios Koutroulakis and H. Yasuoka in the condensed-matter NMR lab at Los Alamos National Laboratory after having observed the magnetic resonance signal of Pu 239 for the first time. Get Expertise Scientist Eric Bauer Condensed Matter & Magnet Science Email Professor Hiroshi Yasuoka Japan Atomic Energy Agency "This discovery of the plutonium 239 magnetic resonance promises to revolutionize our understanding of plutonium solid state physics, chemistry, biology and materials science."

9

GEOCHEMICAL CONTROLS ON NUCLEAR MAGNETIC RESONANCE MEASUREMENTS  

Science Conference Proceedings (OSTI)

Proton nuclear magnetic resonance (NMR) is used in the Earth Sciences as a means of obtaining information about the molecular-scale environment of fluids in porous geological materials. Laboratory experiments were conducted to advance our fundamental understanding of the link between the NMR response and the geochemical properties of geological materials. In the first part of this research project, we studied the impact of both the surface-area-to-volume ratio (S/V) of the pore space and the surface relaxivity on the NMR response of fluids in sand-clay mixtures. This study highlighted the way in which these two parameters control our ability to use NMR measurements to detect and quantify fluid saturation in multiphase saturated systems. The second part of the project was designed to explore the way in which the mineralogic form of iron, as opposed to simply the concentration of iron, affects the surface relaxation rate and, more generally, the NMR response of porous materials. We found that the magnitude of the surface relaxation rate was different for the various iron-oxide minerals because of changes in both the surface-area-to-volume ratio of the pore space, and the surface relaxivity. Of particular significance from this study was the finding of an anomalously large surface relaxivity of magnetite compared to that of the other iron minerals. Differences in the NMR response of iron minerals were seen in column experiments during the reaction of ferrihydrite-coated quartz sand with aqueous Fe(II) solutions to form goethite, lepidocrocite and magnetite; indicating the potential use of NMR as a means of monitoring geochemical reactions. The final part of the research project investigated the impact of heterogeneity, at the pore-scale, on the NMR response. This work highlighted the way in which the geochemistry, by controlling the surface relaxivity, has a significant impact on the link between NMR data and the microgeometry of the pore space.

Rosemary Knight

2008-08-25T23:59:59.000Z

10

An Improved Nuclear Vector Replacement Algorithm for Nuclear Magnetic Resonance Assignment  

E-Print Network (OSTI)

An Improved Nuclear Vector Replacement Algorithm for Nuclear Magnetic Resonance Assignment to the Nuclear Vector Replacement (NVR) algorithm [24] for high-throughput Nuclear Magnetic Resonance (NMR% accu- racy) on the same test suite examined in [24], and runs in O(n5/2 log (cn)) time where n

11

Nuclear Magnetic Resonance Implementation of a Quantum Clock Synchronization Algorithm  

E-Print Network (OSTI)

The quantum clock synchronization algorithm proposed by I. L. Chuang (Phys. Rev. Lett, 85, 2006(2000)) has been implemented in a three qubit nuclear magnetic resonance quantum system. The effective-pure state is prepared by the spatial averaging approach. The time difference between two separated clocks can be determined by reading out directly through the NMR spectra.

Jingfu Zhang; Guilu Long; Zhiwei Deng; Wenzhang Liu; Zhiheng Lu

2004-06-27T23:59:59.000Z

12

Proposed Detection of Dynamically Oriented Nuclei by Acoustic Nuclear Magnetic Resonance  

Science Conference Proceedings (OSTI)

It is proposed that acoustic nuclear magnetic resonance be used to detect steady?state nuclear orientation achieved by the Jeffries Abragam effect. This is a new scheme for double magnetic resonance (ADMR) in contrast with conventional DMR

Mary Duns Scotus Breitbart; W. A. Barker

1967-01-01T23:59:59.000Z

13

I. I. Rabi, Nuclear Magnetic Resonance (NMR), and Radar  

NLE Websites -- All DOE Office Websites (Extended Search)

I. I. Rabi, Nuclear Magnetic Resonance (NMR), and Radar I. I. Rabi, Nuclear Magnetic Resonance (NMR), and Radar Resources with Additional Information I.I. Rabi Courtesy of Brookhaven National Laboratory 'Isidor Isaac Rabi [was] a pioneer in exploring the atom and a major force in 20th-century physics.'1 He won the 1944 Nobel Prize in Physics "for his resonance method for recording the magnetic properties of atomic nuclei". 'His work in turn made possible the precise measurements necessary for the development of the atomic clock, the laser and the diagnostic scanning of the human body by nuclear magnetic resonance. '1 In 1929, Dr. Rabi started working at Columbia University, where he conducted molecular beam research. However, 'Rabi did not relish the task of coaxing from a departmental chairman or dean even the relatively modest funds needed for molecular beam equipment.'2 When Harold Urey, a professor at Columbia, won the 1934 Nobel Prize in Chemistry for his discovery of deuterium, he also received 'an award from the Carnegie Foundation of about $8,000 to assist his research. Urey had no immediate need of this munificence'2 and gave part of it to Dr. Rabi 'so he could continue his research. By 1937 that research had led him to the technique for which he won his Nobel Prize. '1

14

Edward Purcell and Nuclear Magnetic Resonance (NMR)  

Office of Scientific and Technical Information (OSTI)

a large audience of physicists. Purcell's stunning introductory textbook on Electricity and Magnetism has educated and inspired a generation of physicists, who refer to it...

15

Observation of the uranium 235 nuclear magnetic resonance signal (*)  

E-Print Network (OSTI)

L-1017 Observation of the uranium 235 nuclear magnetic resonance signal (*) H. Le Bail, C. Chachaty signal de résonance magnétique nucléaire de l'isotope 235 de l'uranium est présentée. Elle a été effectuée sur l'hexafluorure d'uranium pur, à l'état liquide à 380 K. Le rapport gyromagnétique mesuré est

Paris-Sud XI, Université de

16

Experimental Test of Complementarity by Nuclear Magnetic Resonance Techniques  

E-Print Network (OSTI)

We have tested complementarity for the ensemble-averaged spin states of nuclei $^{13}$C in the molecule of $^{13}$CHCl$_{3}$ by the use of the spin states of another nuclei $^{1}$H as the path marker. It turns out that the wave-particle duality holds when one merely measures the probability density of quantum states, and that the wave- and particle-like behavior is simultaneously observed with the help of measuring populations and coherence in a single nuclear magnetic resonance(NMR) experiment. Effects of path-marking schemes and causes of the appearance and disappearance of the wave behavior are analysed.

Xiwen Zhu; Ximing Fang; Xinhua Peng; Mang Feng; Kelin Gao; Fei Du

2000-11-22T23:59:59.000Z

17

DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers  

DOE Patents (OSTI)

A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced.

Fan, Non Q. (San Diego, CA); Clarke, John (Berkeley, CA)

1993-01-01T23:59:59.000Z

18

DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers  

DOE Patents (OSTI)

A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced. 7 figures.

Fan, N.Q.; Clarke, J.

1993-10-19T23:59:59.000Z

19

Nuclear magnetic resonance experiments with dc SQUID amplifiers  

Science Conference Proceedings (OSTI)

The development and fabrication of dc SQUIDs (Superconducting QUantum Interference Devices) with Nb/Al{sub 2}O{sub 3}/Nb Josephson junctions is described. A theory of the dc SQUID as a radio-frequency amplifier is presented, with an optimization strategy that accounts for the loading and noise contributions of the postamplifier and maximizes the signal-to-noise ratio of the total system. The high sensitivity of the dc SQUID is extended to high field NMR. A dc SQUID is used as a tuned radio-frequency amplifier to detect pulsed nuclear magnetic resonance at 32 MHz from a metal film in a 3.5 Tesla static field. A total system noise temperature of 11 K has been achieved, at a bath temperature of 4.2 K. The minimum number of nuclear Bohr magnetons observable from a free precession signal after a single pulse is about 2 {times} 10{sup 17} in a bandwidth of 25 kHz. In a separate experiment, a dc SQUID is used as a rf amplifier in a NQR experiment to observe a new resonance response mechanism. The net electric polarization of a NaClO{sub 3} crystal due to the precessing electric quadrupole moments of the Cl nuclei is detected at 30 MHz. The sensitivity of NMR and NQR spectrometers using dc SQUID amplifiers is compared to the sensitivity of spectrometers using conventional rf amplifiers. A SQUID-based spectrometer has a voltage sensitivity which is comparable to the best achieved by a FET-based spectrometer, at these temperatures and operating frequencies.

Heaney, M.B. (California Univ., Berkeley, CA (USA). Dept. of Physics Lawrence Berkeley Lab., CA (USA))

1990-11-01T23:59:59.000Z

20

Nuclear magnetic resonance studies of macroscopic morphology and dynamics  

Science Conference Proceedings (OSTI)

Nuclear magnetic resonance techniques are traditionally used to study molecular level structure and dynamics with a noted exception in medically applied NMR imaging (MRI). In this work, new experimental methods and theory are presented relevant to the study of macroscopic morphology and dynamics using NMR field gradient techniques and solid state two-dimensional exchange NMR. The goal in this work is not to take some particular system and study it in great detail, rather it is to show the utility of a number of new and novel techniques using ideal systems primarily as a proof of principle. By taking advantage of the analogy between NMR imaging and diffraction, one may simplify the experiments necessary for characterizing the statistical properties of the sample morphology. For a sample composed of many small features, e.g. a porous medium, the NMR diffraction techniques take advantage of both the narrow spatial range and spatial isotropy of the sample`s density autocorrelation function to obtain high resolution structural information in considerably less time than that required by conventional NMR imaging approaches. The time savings of the technique indicates that NMR diffraction is capable of finer spatial resolution than conventional NMR imaging techniques. Radio frequency NMR imaging with a coaxial resonator represents the first use of cylindrically symmetric field gradients in imaging. The apparatus as built has achieved resolution at the micron level for water samples, and has the potential to be very useful in the imaging of circularly symmetric systems. The study of displacement probability densities in flow through a random porous medium has revealed the presence of features related to the interconnectedness of the void volumes. The pulsed gradient techniques used have proven successful at measuring flow properties for time and length scales considerably shorter than those studied by more conventional techniques.

Barrall, G.A. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States). Materials Science Div.

1995-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Distinguishing Carbonate Reservoir Pore Facies with Nuclear Magnetic Resonance Measurements  

Science Conference Proceedings (OSTI)

Characterization of carbonate rocks may involve identifying the important pore types which are present. In the past, this task has required detailed petrographic analysis of many core samples. Here, we describe a method which uses nuclear magnetic resonance (NMR) measurements to reduce the amount of petrographic analysis needed for porosity typing of carbonate reservoir rocks.For a rock sample which has been measured with NMR, our method decomposes the log(T{sub 2}) spectrum into at most three Gaussian-shaped components and gives a set of nine parameters. Two characteristic quantities having geological significance are extracted from the nine parameters. Values of the two quantities are compared with a reference set, established from samples having both NMR and petrographic evaluations of porosity types. We use a Bayesian approach to the classification of the dominant porosity type.Tests of our method on 103 samples show a correct prediction in 60 to 90 percent of the samples. The lower success rate was obtained for samples with five porosity types from three fields; the higher success rate obtained with samples with three porosity types from one well. The use of geologically significant quantities extracted from the decomposition gives comparable success rate to those obtained using a standard, non-geological approach such as canonical variates.

Genty, Coralie [ExxonMobil Production Company (United States); Jensen, Jerry L. [University of Calgary, Department of Chemical and Petroleum Engineering (Canada)], E-mail: jjensen@ucalgary.ca; Ahr, Wayne M. [Texas A and M University, Department of Geology and Geophysics (United States)

2007-03-15T23:59:59.000Z

22

RESEARCH Open Access H low field nuclear magnetic resonance  

E-Print Network (OSTI)

magnetic resonance, Biodiesel, Biodiesel physical properties, Chemometrics, Laplace inversion of biodiesel Paula Berman1 , Adi Leshem1 , Oren Etziony1 , Ofer Levi2 , Yisrael Parmet2 , Michael Saunders3 and Zeev Wiesman1* Abstract Background: Biodiesel production has increased dramatically over the last

Stanford University

23

Bounds on the entanglability of thermal states in liquid-state nuclear magnetic resonance  

E-Print Network (OSTI)

Theorists have recently shown that the states used in current nuclear magnetic resonance (NMIR) quantum computing experiments are not entangled. Yet it is widely believed that entanglement is a necessary resource in the ...

Yu, Terri M. (Terri Mak), 1981-

2003-01-01T23:59:59.000Z

24

An ant colony optimization approach for solving the nuclear magnetic resonance structure based assignment problem  

Science Conference Proceedings (OSTI)

Nuclear Magnetic Resonance (NMR) Spectroscopy is an important technique that allows determining protein structure in solution. An important problem in protein structure determination using NMR spectroscopy is the mapping of peaks to corresponding amino ... Keywords: ant colony optimization, backbone resonance assignments, n15-labeled, nmr

Jeyhun Aslanov; Blent atay; Mehmet Serkan Apaydin

2013-07-01T23:59:59.000Z

25

New Methodology For Use in Rotating Field Nuclear Magnetic Resonance  

E-Print Network (OSTI)

MHz and the permanent magnets motors mechanical rotationa stepping motor held away from the magnet, a pulley system,permanent magnet mechanically is rotated with a motor while

Jachmann, Rebecca C.

2007-01-01T23:59:59.000Z

26

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials  

DOE Patents (OSTI)

An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

Kraus, Robert H. (Los Alamos, NM); Matlashov, Andrei N. (Los Alamos, NM); Espy, Michelle A. (Los Alamos, NM); Volegov, Petr L. (Los Alamos, NM)

2010-03-30T23:59:59.000Z

27

Nuclear magnetic resonance apparatus having semitoroidal rf coil for use in topical NMR and NMR imaging  

DOE Patents (OSTI)

An improved nuclear magnetic resonance (NMR) apparatus for use in topical magnetic resonance (TMR) spectroscopy and other remote sensing NMR applications includes a semitoroidal radio-frequency (rf) coil. The semitoroidal rf coil produces an effective alternating magnetic field at a distance from the poles of the coil, so as to enable NMR measurements to be taken from selected regions inside an object, particularly including human and other living subjects. The semitoroidal rf coil is relatively insensitive to magnetic interference from metallic objects located behind the coil, thereby rendering the coil particularly suited for use in both conventional and superconducting NMR magnets. The semitoroidal NMR coil can be constructed so that it emits little or no excess rf electric field associated with the rf magnetic field, thus avoiding adverse effects due to dielectric heating of the sample or to any other interaction of the electric field with the sample.

Fukushima, Eiichi (Los Alamos, NM); Roeder, Stephen B. W. (La Mesa, CA); Assink, Roger A. (Albuquerque, NM); Gibson, Atholl A. V. (Bryan, TX)

1986-01-01T23:59:59.000Z

28

A nuclear magnetic resonance probe of group IV clathrates  

E-Print Network (OSTI)

The clathrates feature large cages of silicon, germanium, or tin, with guest atoms in the cage centers. The group IV clathrates are interesting because of their thermoelectric efficiency, and their glasslike thermal conductivity at low temperatures. Clathrates show a variety of properties, and the motion of cage center atoms is not well understood. In Sr8Ga16Ge30, we found that the slow atomic motion in the order 10-5 s is present in this system, which is much slower than what would be expected for standard atomic dynamics. NMR studies of Sr8Ga16Ge30 showed that Knight shift and T1 results are consistent with low density metallic behavior. The lineshapes exhibit changes consistent with motional narrowing at low temperatures, and this indicates unusually slow hopping rates. To further investigate this behavior, we made a series of measurements using the Carr-Purcell-Meiboom-Gill NMR sequence. Fitting the results to a hopping model yielded an activation energy of 4.6 K. We can understand all of our observations in terms of non-resonant atomic tunneling between asymmetric sites within the cages, in the presence of disorder. For Ba8Ga16Ge30, the relaxation behavior (T1) deviates from the Korringa relation, and the Knight shift and linewidth change with temperature. Those results could be explained by carrier freezout, and the development of a dilute set of magnetic moments due to these localized carriers. For Ba8Ga16Ge30 samples made from Ga flux, we observed different T1 and Knight shift behavior as compared to n type material. This is due to the differences in carrier type among these different samples. The p type sample has a smaller Knight shift and a slower relaxation rate than n type samples made with the stoichiometric ratio, which is consistent with a change in orbital symmetry between the conduction and valence bands. WDS study for Ba8Al10Ge36 showed the existence of vacancies in the Al-deficient samples, which results in some degree of ordering of Al occupation on the framework sites. In Al NMR measurements on Ba8AlxGe40-x with x = 12 to 16, we found that T1 of all Al samples follows the Korringa relation. The broadening of the single NMR central peak of Ba8Al16Ge30 is due to the inhomogeneous Knight shifts for occupation of different framework sites. For Ba8Al12Ge34 and Ba8Al13Ge33, we observed two peaks, and NMR results show that they are from distinct Al sites, while for each peak, the inhomogeneous broadening is much smaller. The difference in lineshapes we attributed to the existence of vacancies which we detected in the Al-deficient materials, and we assign one of the two Al peaks to Al adjacent to a vacancy.

Gou, Weiping

2008-08-01T23:59:59.000Z

29

Direct current superconducting quantum interference device spectrometer for pulsed nuclear magnetic resonance and nuclear quadrupole resonance at frequencies up to 5 MHz  

Science Conference Proceedings (OSTI)

A spectrometer based on a dc superconducting quantum interference device (SQUID) has been developed for the direct detection of nuclear magnetic resonance (NMR) or nuclear quadrupole resonance (NQR) at frequencies up to 5 MHz. The sample is coupled to the input coil of the niobium-based SQUID via a nonresonant superconducting circuit. The flux locked loop involves the direct offset integration technique with additional positive feedback in which the output of the SQUID is coupled directly to a low-noise preamplifier. Precession of the nuclear quadrupole spins is induced by a magnetic field pulse with the feedback circuit disabled; subsequently, flux locked operation is restored and the SQUID amplifies the signal produced by the nuclear free induction signal. The spectrometer has been used to detect {sup 27}Al NQR signals in ruby (Al{sub 2}O{sub 3}[Cr{sup 3+}]) at 359 and 714 kHz. {copyright} {ital 1996 American Institute of Physics.}

TonThat, D.M.; Clarke, J. [Department of Physics, University of , California (United States)]|[Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

1996-08-01T23:59:59.000Z

30

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance  

NLE Websites -- All DOE Office Websites (Extended Search)

Non-medical Uses of Computed Tomography (CT) Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance (NMR) Resources with Additional Information Computed Tomography (CT) Scanner CT Scanner - Courtesy Stanford University Department of Energy Resources Engineering Computed tomography (CT) and Nuclear Magnetic Resonance (NMR) have been used to resolve industrial problems, for materials characterizations, and to provide non-destructive evaluations for discovering flaws in parts before their use, resulting in greater reliability and greater safety for workers; to identify the presence and facilitate the recovery/extraction of oil, water, coal, and/or gas; and to provide non-destructive testing and quality control of fresh fruits and vegetables, enhancing the safety of food. These benefits of non-medical uses of CT and NMR contribute to the economy and improve people's lives.

31

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance  

Office of Scientific and Technical Information (OSTI)

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance (NMR) Resources with Additional Information Computed Tomography (CT) Scanner CT Scanner - Courtesy Stanford University Department of Energy Resources Engineering Computed tomography (CT) and Nuclear Magnetic Resonance (NMR) have been used to resolve industrial problems, for materials characterizations, and to provide non-destructive evaluations for discovering flaws in parts before their use, resulting in greater reliability and greater safety for workers; to identify the presence and facilitate the recovery/extraction of oil, water, coal, and/or gas; and to provide non-destructive testing and quality control of fresh fruits and vegetables, enhancing the safety of food. These benefits of non-medical uses of CT and NMR contribute to the economy and improve people's lives.

32

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

Potential of Nuclear Resonance Fluorescence . . . . . . . .2.9.1 Nuclear ThomsonSections . . . . . . . . . . . . . . . Nuclear Resonance

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

33

Solid state nuclear magnetic resonance methodology and applications to structure determination of peptides, proteins and amyloid fibrils  

E-Print Network (OSTI)

Several methodological developments and applications of multidimensional solid-state nuclear magnetic resonance to biomolecular structure determination are presented. Studies are performed in uniformly 3C, 15N isotope ...

Jaroniec, Christopher P

2003-01-01T23:59:59.000Z

34

Method of using a nuclear magnetic resonance spectroscopy standard  

DOE Patents (OSTI)

(CH.sub.3).sub.3 SiNSO is produced by the reaction of ((CH.sub.3).sub.3 Si).sub.2 NH with SO.sub.2. Also produced in the reaction are ((CH.sub.3).sub.3 Si).sub.2 O and a new solid compound [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ]. Both (CH.sub.3).sub.3 SiNSO and [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO.sub.2 pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH.sub.3).sub.3 Si).sub.2 NH, whereby any SO.sub.2 present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO.sub.2 in the original gas sample. The solid product [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] may be used as a standard in solid state NMR spectroscopy, wherein the resonance peaks of either .sup.1 H, .sup.13 C, .sup.15 N, or .sup.29 Si may be used as a reference.

Spicer, Leonard D. (Salt Lake City, UT); Bennett, Dennis W. (Clemson, SC); Davis, Jon F. (Salt Lake City, UT)

1985-01-01T23:59:59.000Z

35

Magnetic Resonance Facility (Fact Sheet)  

DOE Green Energy (OSTI)

This fact sheet provides information about Magnetic Resonance Facility capabilities and applications at NREL's National Bioenergy Center. Liquid and solid-state analysis capability for a variety of biomass, photovoltaic, and materials characterization applications across NREL. NREL scientists analyze solid and liquid samples on three nuclear magnetic resonance (NMR) spectrometers as well as an electron paramagnetic resonance (EPR) spectrometer.

Not Available

2012-03-01T23:59:59.000Z

36

Dynamics of lipid bilayers from comparative analysis of 2 nuclear magnetic resonance relaxation data as a function  

E-Print Network (OSTI)

to the predominant mechanisms of nuclear spin relax- ation in lipid bilayers. To critically test various dDynamics of lipid bilayers from comparative analysis of 2 H and 13 C nuclear magnetic resonance September 1997 Analysis of the nuclear spin relaxation rates of lipid membranes provides a powerful means

Brown, Michael F.

37

Two Phase Flow Measurements by Nuclear Magnetic Resonance (NMR)  

SciTech Connect

In concentrated suspensions, there is a tendency for the solid phase to migrate from regions of high shear rate to regions of low shear (Leighton & Acrivos, 1987). In the early years that our effort was funded by the DOE Division of Basic Energy Science, quantitative measurement of this process in neutrally buoyant suspensions was a major focus (Abbott, et al., 1991; Altobelli, et al., 1991). Much of this work was used to improve multi-phase numerical models at Sandia National Laboratories. Later, our collaborators at Sandia and the University of New Mexico incorporated body forces into their numerical models of suspension flow (Rao, Mondy, Sun, et al., 2002). We developed experiments that allow us to study flows driven by buoyancy, to characterize these flows in well-known and useful engineering terms (Altobelli and Mondy, 2002) and to begin to explore the less well-understood area of flows with multiple solid phases (Beyea, Altobelli, et al., 2003). We also studied flows that combine the effects of shear and buoyancy, and flows of suspensions made from non-Newtonian liquids (Rao, Mondy, Baer, et al, 2002). We were able to demonstrate the usefulness of proton NMR imaging of liquid phase concentration and velocity and produced quantitative data not obtainable by other methods. Fluids flowing through porous solids are important in geophysics and in chemical processing. NMR techniques have been widely used to study liquid flow in porous media. We pioneered the extension of these studies to gas flows (Koptyug, et al, 2000, 2000, 2001, 2002). This extension allows us to investigate a wider range of Peclet numbers, and to gather data on problems of interest in catalysis. We devised two kinds of NMR experiments for three-phase systems. Both experiments employ two NMR visible phases and one phase that gives no NMR signal. The earlier method depends on the two visible phases differing in a NMR relaxation property. The second method (Beyea, Altobelli, et al., 2003) uses two different nuclei, protons and 19F. It also uses two different types of NMR image formation, a conventional spin-echo and a single-point method. The single-point method is notable for being useful for imaging materials which are much more rigid than can usually be studied by NMR imaging. We use it to image low density polyethylene (LDPE) plastic in this application. We have reduced the imaging time for this three-phase imaging method to less than 10 s per pair of profiles by using new hardware. Directly measuring the solid LDPE signal was a novel feature for multi-phase flow studies. We also used thermally polarized gas NMR (as opposed to hyper-polarized gas) which produces low signal to noise ratios because gas densities are on the order of 1000 times smaller than liquid densities. However since we used multi-atom molecules that have short T1's and operated at elevated pressures we could overcome some of the losses. Thermally polarized gases have advantages over hyperpolarized gases in the ease of preparation, and in maintaining a well-defined polarization. In these studies (Codd and Altobelli, 2003), we used stimulated echo sequences to successfully obtain propagators of gas in bead packs out to observation times of 300 ms. Zarraga, et al. (2000) used laser-sheet profilometry to investigate normal stress differences in concentrated suspensions. Recently we developed an NMR imaging analog for comparison with numerical work that is being performed by Rekha Rao at Sandia National Laboratories (Rao, Mondy, Sun, et al, 2002). A neutrally buoyant suspension of 100 mm PMMA spheres in a Newtonian liquid was sheared in a vertical Couette apparatus inside the magnet. The outer cylinder rotates and the inner cylinder is fixed. At these low rotation rates, the free-surface of the Newtonian liquid shows no measurable deformation, but the suspension clearly shows its non-Newtonian character.

Altobelli, Stephen A; Fukushima, Eiichi

2006-08-14T23:59:59.000Z

38

Nuclear-electronic spin systems, magnetic resonance, and quantum information processing  

E-Print Network (OSTI)

A promising platform for quantum information processing is that of silicon impurities, where the quantum states are manipulated by magnetic resonance. Such systems, in abstraction, can be considered as a nucleus of arbitrary spin coupled to an electron of spin one-half via an isotropic hyperfine interaction. We therefore refer to them as "nuclear-electronic spin systems". The traditional example, being subject to intensive experimental studies, is that of phosphorus doped silicon (Si:P) which couples a spin one-half electron to a nucleus of the same spin, with a hyperfine strength of 117.5 MHz. More recently, bismuth doped silicon (Si:Bi) has been suggested as an alternative instantiation of nuclear-electronic spin systems, differing from Si:P by its larger nuclear spin and hyperfine strength of 9/2 and 1.4754 GHz respectively. The aim of this thesis has been to develop a model that is capable of predicting the magnetic resonance properties of nuclear-electronic spin systems. The theoretical predictions of this model have been tested against experimental data collected on Si:Bi at 4.044 GHz, and have proven quite successful. Furthermore, the larger nuclear spin and hyperfine strength of Si:Bi, compared with that of Si:P, are predicted to offer advantages for quantum information processing. Most notable amongst these is that magnetic field-dependent two-dimensional decoherence free subspaces, called optimal working points, have been identified to exist in Si:Bi, but not Si:P.

M. H. Mohammady

2013-04-30T23:59:59.000Z

39

Speedup of quantum state transfer by three- qubit interactions: Implementation by nuclear magnetic resonance  

E-Print Network (OSTI)

Universal quantum information processing requires single-qubit rotations and two-qubit interactions as minimal resources. A possible step beyond this minimal scheme is the use of three-qubit interactions. We consider such three-qubit interactions and show how they can reduce the time required for a quantum state transfer in an XY spin chain. For the experimental implementation, we use liquid-state nuclear magnetic resonance (NMR), where three-qubit interactions can be implemented by sequences of radio-frequency pulses.

Jingfu Zhang; Xinhua Peng; Dieter Suter

2005-12-25T23:59:59.000Z

40

Development of Nuclear Magnetic Resonance Imaging/spectroscopy for improved petroleum recovery. Final report  

SciTech Connect

The overall objectives of this program are to develop and apply Nuclear Magnetic Resonance Imaging (NMRI) and CT X-Ray Scanning methods for determining rock, fluid, and petrophysical properties and for fundamental studies of multiphase flow behavior in porous media. Specific objectives are divided into four subtasks: (1) development of NMRI and CT scanning for the determination of rock-fluid and petrophysical properties; (2) development of NMRI and CT scanning for characterizing conventional multiphase displacement processes; (3) development of NMR and CT scanning for characterizing dispersed phase processes; and (4) miscible displacement studies.

Barrufet, M.A.; Flumerfelt, F.W.; Walsh, M.P.; Watson, A.T.

1994-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Cranial anatomy and detection of ischemic stroke in the cat by nuclear magnetic resonance imaging  

SciTech Connect

Proton nuclear magnetic resonance (NMR) images of cat heads were obtained using a small, experimental imaging system. As a prelude to the study of experimental ischemic brain infarction, the normal cat head was imaged for identification of anatomical features. Images of one cat which had undergone ligation of the middle cerebral artery three weeks previously showed brain changes associated with chronic ischemic stroke and compared favorably with findings on computed tomography (CT). The NMR images have millimetric spatial resolution. NMR parameters inherent in the tissues provide intensity variations and are sufficiently sensitive to yield contrast resolution surpassing that of CT.

Buonanno, F.S.; Pykett, I.L.; Kistler, J.P.; Vielma, J.; Brady, T.J.; Hinshaw, W.S.; Goldman, M.R.; Newhouse, J.H.; Pohost, G.M.

1982-04-01T23:59:59.000Z

42

Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects  

SciTech Connect

Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I = 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an encoding module for the recently developed NMR remote detection experiment. The feasibility of using hyperpolarized xenon-129 gas as a sensor is discussed. This work also reports the use of an optical atomic magnetometer to detect the nuclear magnetization of Xe-129 gas, which has potential applicability as a detection module for NMR remote detection experiments.

Urban, Jeffry Todd

2004-12-21T23:59:59.000Z

43

Redox-dependent structure change and hyperfine nuclear magnetic resonance shifts in cytochrome c  

SciTech Connect

Proton nuclear magnetic resonance assignments for reduced and oxidized equine cytochrome c show that many individual protons exhibit different chemical shifts in the two protein forms, reflecting diamagnetic shift effects due to structure change, and in addition contact and pseudocontact shifts that occur only in the paramagnetic oxidized form. To evaluate the chemical shift differences for structure change, the authors removed the pseudocontact shift contribution by a calculation based on knowledge of the electron spin g tensor. The g-tensor calculation, when repeated using only 12 available C{sub {alpha}}H proton resonances for cytochrom c from tuna, proved to be remarkably stable. The derived g tensor was then used together with spatial coordinates for the oxidized form to calculate the pseudocontact shift contribution to proton resonances at 400 identifiable sites throughout the protein, so that the redox-dependent chemical shift discrepancy, could be evaluated. Large residual changes in chemical shift define the Fermi contact shifts, where are found as expected to be limited to the immediate covalent structure of the heme and its ligands and to be asymmetrically distributed over the heme. The chemical shift discrepancies observed appear in the main to reflect structure-dependent diamagnetic shifts rather than hyperfine effects due to displacements in the pseudocontact shift field. Although 51 protons in 29 different residues exhibit significant chemical shift changes, the general impressions one of small structural adjustments to redox-dependent strain rather than sizeable structural displacements or rearrangements.

Feng, Yiquing; Roder, H.; Englander, S.W. (Univ. of Pennsylvania, Philadelphia (USA))

1990-04-10T23:59:59.000Z

44

Rapid determination of sugar content in biomass hydrolysates using nuclear magnetic resonance spectroscopy  

NLE Websites -- All DOE Office Websites (Extended Search)

Biofuels and Environmental Biotechnology Biotechnology and Bioengineering Biofuels and Environmental Biotechnology Biotechnology and Bioengineering DOI 10.1002/bit.24741 Rapid determination of sugar content in biomass hydrolysates using nuclear magnetic resonance spectroscopy † Erica Gjersing*, Renee M. Happs, Robert W. Sykes, Crissa Doeppke, and Mark F. Davis National Bioenergy Center, National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, CO 80401 *Address correspondence to: Erica.Gjersing@nrel.gov; phone: 303-384-7984; fax: 303-384- 6363 Key Words: hydrolysate, Partial Least Squares, 1H NMR, PLS regression † This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to

45

The Determination of Deuterium and Tritium in Effluent Wastewater by Pulsed Nuclear Magnetic Resonance Spectroscopy  

SciTech Connect

A pulsed nuclear magnetic resonance (NMR) procedure was developed for the quantitative determination of deuterium and tritium in radioactive, effluent, wastewater to aid in the design of an efficient combined electrolytic/catalytic exchange system for the recovery of these hydrogen isotopes. The deuterium and tritium NMR signals were observed at 9.210 and 45.7 MHz, respectively. Ten different effluent water samples were analyzed for deuterium and tritium to establish base-line data for the preparation of standard reference samples. The hydrogen isotope concentrations ranged from 0.11 to 2.40 g deuterium and from 2.0 to 21.0 mg tritium per liter of processed sample. The standard deviation of the hydrogen isotope determinations is +- 0.017 g deuterium and +- 0.06 mg tritium per liter of processed effluent water. In the future, the effectiveness of specially prepared and analyzed (calorimetry) effluent samples as tritium standards will be investigated.

Attalla, A.; Birkbeck, J. C.

1985-04-01T23:59:59.000Z

46

Evaluation Of Automated Low-Field Nuclear Magnetic Resonance (NMR) Relaxometry For Analysis Of Silicone Polymers  

Science Conference Proceedings (OSTI)

Screening studies and Design of Experiments (DoE) were performed to evaluate measurement variation of a new, non-destructive Nuclear Magnetic Resonance (NMR) test system designed to assess age-induced degradation of Outer Pressure Pads (OPP). The test method and results from 54,275 measurements are described. A reduction in measurement error was obtained after metal support struts were replaced with plastic support struts adjacent to the front position of the test chamber. However, remaining interference and a lack of detecting any age-related degradation prevent the use of the NMR system as a non-destructive surveillance test for OPPs. A cursory evaluation of the system with cellular silicone samples obtained more uniform results with increased error as measurements approached the samples edge.

M. H. Wilson

2009-10-02T23:59:59.000Z

47

Three path interference using nuclear magnetic resonance: a test of the consistency of Born's rule  

E-Print Network (OSTI)

The Born rule is at the foundation of quantum mechanics and transforms our classical way of understanding probabilities by predicting that interference occurs between pairs of independent paths of a single object. One consequence of the Born rule is that three way (or three paths) quantum interference does not exist. In order to test the consistency of the Born rule, we examine detection probabilities in three path intereference using an ensemble of spin-1/2 quantum registers in liquid state nuclear magnetic resonance (LSNMR). As a measure of the consistency, we evaluate the ratio of three way interference to two way interference. Our experiment bounded the ratio to the order of $10^{-3} \\pm 10^{-3}$, and hence it is consistent with Born's rule.

Daniel K. Park; Osama Moussa; Raymond Laflamme

2012-07-10T23:59:59.000Z

48

Improved nuclear magnetic resonance apparatus having semitoroidal rf coil for use in topical NMR and NMR imaging  

DOE Patents (OSTI)

An improved nuclear magnetic resonance (NMR) apparatus for use in topical magnetic resonance (TMR) spectroscopy and other remote sensing NMR applications includes a semitoroidal radio frequency (rf) coil. The semitoroidal rf coil produces an effective alternating magnetic field at a distance from the poles of the coil, so as to enable NMR measurements to be taken from selected regions inside an object, particularly including human and other living subjects. The semitoroidal rf coil is relatively insensitive to magnetic interference from metallic objects located behind the coil, thereby rendering the coil particularly suited for use in both conventional and superconducting NMR magnets. The semitoroidal NMR coil can be constructed so that it emits little or no excess rf electric field associated with the rf magnetic field, thus avoiding adverse effects due to dielectric heating of the sample or to any other interaction of the electric field with the sample.

Fukushima, E.; Roeder, S.B.W.; Assink, R.A.; Gibson, A.A.V.

1984-01-01T23:59:59.000Z

49

Nuclear magnetic resonance wide-line study of hydrogen in the yttrium-yttrium dihydride system  

DOE Green Energy (OSTI)

The /sup 1/H nuclear magnetic resonance was studied in the yttrium-hydrogen system YH/sub x/ in the composition range 0.20 less than or equal to x less than or equal to 1.98 and temperature range 77 K less than or equal to T less than or equal to 490/sup 0/K. Both ..cap alpha..- and ..beta..-phases of YH/sub x/ were investigated in polycrystalline (powdered) specimens. Rigid lattice proton resonance second moments were obtained for both ..cap alpha..- and ..beta..-phase samples. Analysis of the second moment for ..cap alpha..-YH/sub x/ (..cap alpha..-phase) indicates that the hydrogen resides in both the tetrahedral and octahedral interstitial sites of the hcp Y lattice. Second moment values for ..beta..-YH/sub x/ (..beta..-phase) indicate that a sizeable fraction of the octahedral interstitial sites in the fcc yttrium metal lattice are occupied by hydrogen, while a nonnegligible fraction of the tetrahedral interstitial sites are vacant. For example, in YH/sub 1.98/, 28% of the octahedral sites are occupied, while 15% of the tetrahedral sites are vacant. The results for ..beta..-YH/sub x/ also indicate that as the H concentration increases, the probability of H occupation of octahedral sites increases.

Anderson, D.L.

1980-03-01T23:59:59.000Z

50

Characterization of proton exchange membrane materials for fuel cells by solid state nuclear magnetic resonance  

Science Conference Proceedings (OSTI)

Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated. The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by small-angle X-ray scattering (SAXS). The S/V ratios of different Nafion models have been evaluated numerically. It has been found that only the water channel model gives the measured S/V ratios in the normal hydration range of a working fuel cell, while dispersed water molecules and polymer ribbons account for the structures at low and high hydration levels, respectively.

Kong, Zueqian

2010-03-15T23:59:59.000Z

51

Lithium-7 nuclear magnetic resonance investigation of lithium insertion in hard carbon  

Science Conference Proceedings (OSTI)

Lithium battery anodes based on disordered, hard carbon were prepared by low-temperature (1,000 C) pyrolysis of cotton cloth. Samples were lithiated in an electrochemical cell. The Li insertion (potential vs. capacity) curve exhibits two different regions: a sloping one, from 1.1 to 0.1 V (vs Li/Li{sup +}) denoted as the high-voltage region (HVR), and a plateau between 0.1 and zero V, denoted as the low-voltage plateau (LVP). Lithium-7 high-resolution (magic angle spinning) nuclear magnetic resonance measurements in fully lithiated samples reveal three main features: a broad line at ca. 50 ppm, a relatively sharp line at 17 ppm, with a shoulder at about zero ppm (all shifts relative to aqueous LiCl). The 50 ppm component is attributed to Li intercalated between turbostratically disordered graphene planes and is associated with the LVP part of the potential curve. The 17 ppm signal arises from a Li site which resides in amorphous hydrogen-containing regions of the carbon and is correlated with the HVR part of the curve. The zero ppm component is attributed to the irreversible portion of the Li (up to {approximately} 20% of the total) which constitutes the solid electrolyte interphase on the surface of the carbon grains formed by electrochemical reduction of the electrolyte. These spectral assignments were verified by running other samples which were electrochemically delithiated to varying degrees.

Dai, Y.; Wang, Y.; Greenbaum, S.G. [City Univ. of New York, NY (United States). Dept. of Physics; Eshkenazi, V.; Peled, E. [Tel Aviv Univ., IL (United States). School of Chemistry

1998-04-01T23:59:59.000Z

52

Magnetic moment of Ag-104(m) and the hyperfine magnetic field of Ag in Fe using nuclear magnetic resonance on oriented nuclei  

E-Print Network (OSTI)

Nuclear magnetic resonance (NMR/ON) measurements with beta- and gamma-ray detection have been performed on oriented Ag-104(g,m) nuclei with the NICOLE He-3-He-4 dilution refrigerator setup at ISOLDE/CERN. For Ag-104(g) (I-pi = 5(+)) the gamma-NMR/ON resonance signal was found at nu = 266.70(5) MHz. Combining this result with the known magnetic moment for this isotope, the magnetic hyperfine field of Ag impurities in an Fe host at low temperature (< 1 K) is found to be vertical bar B-hf(AgFe)vertical bar = 44.709(35) T. A detailed analysis of other relevant data available in the literature yields three more values for this hyperfine field. Averaging all four values yields a new and precise value for the hyperfine field of Ag in Fe; that is, vertical bar B-hf(AgFe)vertical bar = 44.692(30) T. For Ag-104(m) (I-pi = 2(+)), the anisotropy of the beta particles provided the NMR/ON resonance signal at nu = 627.7(4) MHz. Using the new value for the hyperfine field of Ag in Fe, this frequency corresponds to the magnetic moment mu(Ag-104m) = +3.691(3) mu(N), which is significantly more precise than previous results. The magnetic moments of the even-A Ag102 -110 isotopes are discussed in view of the competition between the (pi g(9/2))(7/2+)(-3)(nu d(5/2)nu g(7/2))(5/2+) and the (pi g(9/2))(9/2+)(-3)(nu d(5/2)nu g(7/2))(5/2+) configurations. The magnetic moments of the ground and isomeric states of Ag-104 can be explained by an almost complete mixing of these two configurations.

V. V. Golovko; I. S. Kraev; T. Phalet; B. Delaure; M. Beck; V. Yu. Kozlov; S. Coeck; F. Wauters; P. Herzog; Ch. Tramm; D. Zakoucky; D. Venos; D. Srnka; M. Honusek; U. Koester; N. Severijns

2010-06-30T23:59:59.000Z

53

Nuclear magnetic resonance imaging and analysis for determination of porous media properties  

E-Print Network (OSTI)

Advanced nuclear magnetic resonance (NMR) imaging methodologies have been developed to determine porous media properties associated with fluid flow processes. This dissertation presents the development of NMR experimental and analysis methodologies, called NMR probes, particularly for determination of porosity, permeability, and pore-size distributions of porous media while the developed methodologies can be used for other properties. The NMR relaxation distribution can provide various information about porous systems having NMR active nuclei. The determination of the distribution from NMR relaxation data is an ill-posed inverse problem that requires special care, but conventionally the problem has been solved by ad-hoc methods. We have developed a new method based on sound statistical theory that suitably implements smoothness and equality/inequality constraints. This method is used for determination of porosity distributions. A Carr-Purcell-Meiboom-Gill (CPMG) NMR experiment is designed to measure spatially resolved NMR relaxation data. The determined relaxation distribution provides the estimate of intrinsic magnetization which, in turn, is scaled to porosity. A pulsed-field-gradient stimulated-echo (PFGSTE) NMR velocity imaging experiment is designed to measure the superficial average velocity at each volume element. This experiment measures velocity number distributions as opposed to the average phase shift, which is conventionally measured, to suitably quantify the velocities within heterogeneous porous media. The permeability distributions are determined by solving the inverse problem formulated in terms of flow models and the velocity data. We present new experimental designs associated with flow conditions to enhance the accuracy of the estimates. Efforts have been put forth to further improve the accuracy by introducing and evaluating global optimization methods. The NMR relaxation distribution can be scaled to a pore-size distribution once the surface relaxivity is known. We have developed a new method, which avoids limitations on the range of time for which data may be used, to determine surface relaxivity by the PFGSTE NMR diffusion experiment.

Uh, Jinsoo

2005-12-01T23:59:59.000Z

54

Homometallic and Heterometallic Antiferromagnetic Rings: Magnetic Properties Studied by Nuclear Magnetic Resonance  

SciTech Connect

The aim of the present thesis is to investigate the local magnetic properties of homometallic Cr{sub 8} antiferromagnetic (AFM) ring and the changes occurring by replacing one Cr{sup 3+} ion with diamagnetic Cd{sup 2+} (Cr{sub 7}Cd) and with Ni{sup 2+} (Cr{sub 7}Ni). In the heterometallic ring a redistribution of the local magnetic moment is expected in the low temperature ground state. We have investigated those changes by both {sup 53}Cr-NMR and {sup 19}F-NMR. We have determined the order of magnitude of the transferred hyperfine coupling constant {sup 19}F - M{sup +} where M{sup +} = Cr{sup 3+}, Ni{sup 2+} in the different rings. This latter result gives useful information about the overlapping of the electronic wavefunctions involved in the coordinative bond.

Casadei, Cecilia

2012-05-09T23:59:59.000Z

55

Simulation of a Heisenberg XY- chain and realization of a perfect state transfer algorithm using liquid nuclear magnetic resonance  

E-Print Network (OSTI)

The three- spin chain with Heisenberg XY- interaction is simulated in a three- qubit nuclear magnetic resonance (NMR) quantum computer. The evolution caused by the XY- interaction is decomposed into a series of single- spin rotations and the $J$- coupling evolutions between the neighboring spins. The perfect state transfer (PST) algorithm proposed by M. Christandl et al [Phys. Rev. Lett, 92, 187902(2004)] is realized in the XY- chain.

Jingfu Zhang; Gui Lu Long; Wei Zhang; Zhiwei Deng; Wenzhang Liu; Zhiheng Lu

2005-03-25T23:59:59.000Z

56

Development of Nuclear Magnetic Resonance Pulse Sequences and Probes to Study Biomacromolecules  

DOE Green Energy (OSTI)

The determination of the three dimensional structures at high resolution of biomolecules, such as proteins and nucleic acids, enables us to understand their function at the molecular level. At the present time, there are only two methods available for determining such structures, nuclear magnetic resonance (NMR) spectroscopy and X-ray diffraction. Compared to well-established X-ray diffraction techniques, NMR methodology is relatively new and has many areas in which improvement can still be attained. In this project, we focused on the development of new NMR probes and pulse sequences that were tailored to tackle specific problems that are not adequately addressed by current technology. Probes are the hardware that contain the radio frequency (RF) circuitry used to both excite and detect the NMR signals. Pulse sequences are composed of a series of RF pulses and delays, which are applied to the sample held within the magnetic field by the probe, so as to manipulate the nuclear spins. Typically, a probe is developed for a specific set of nuclei and types of experiments and the pulse sequences are then written to use the probe in an optimal manner. In addition, the inter-development of instrumentation and methods are determined by the specific biological question to be examined. Thus our efforts focused on addressing an area of importance in NMR Structural Biology namely more effective ways to use the phosphorus ({sup 31}P) nucleus. Phosphorus is a very important biological element that is strategically located in nucleic acids, where it imparts negative charge and flexibility to RNA and DNA. It is also a component of the cellular membrane and thus interacts with membrane proteins. It is used in mechanisms to signal, activate or deactivate enzymes; and participates in energy storage and release. However, the phosphorus nucleus exhibits certain properties, such as poor spectral dispersion, low sensitivity of detection, and fast relaxation, which limit its effective use in NMR studies of biomolecules. Our unique combination of expertise at LLNL allowed us to tackle each of the negative features of {sup 31}P-NMR in a three-pronged, concerted effort. The nature of our work necessitated an interdependent, multidisciplinary approach that required knowledge of spin physics (pulse sequences), engineering (probes), and structural biology (sample preparation and structure determination).

Cosman, M; Krishnan, V V; Maxwell, R

2001-02-26T23:59:59.000Z

57

Quantitative Determination of Chemical Processes by Dynamic Nuclear Polarization Enhanced Nuclear Magnetic Resonance Spectroscopy  

E-Print Network (OSTI)

Dissolution dynamic nuclear polarization (DNP) provides several orders of magnitude of NMR signal enhancement by converting the much larger electron spin polarization to nuclear spin polarization. Polarization occurs at low temperature (1.4K) and is followed by quickly dissolving the sample for room temperature NMR detection. DNP is generally applicable to almost any small molecules and can polarize various nuclei including 1H, 19F and 13C. The large signal from DNP enhancement reduces the limit of detection to micromolar or sub-micromolar concentration in a single scan. Since DNP enhancement often provides the only source for the observable signal, it enables tracking of the polarization flow. Therefore, DNP is ideal for studying chemical processes. Here, quantitative tools are developed to separate kinetics and spin relaxation, as well as to obtain structural information from these measurements. Techniques needed for analyzing DNP polarized sample are different from those used in conventional NMR because a large, yet non-renewable hyperpolarization is available. Using small flip angle pulse excitation, the hyperpolarization can still be divided into multiple scans. Based on this principle, a scheme is presented that allows reconstruction of indirect spectral dimensions similarly to conventional 2D NMR. Additionally, small flip angle pulses can be used to obtain a succession of scans separated in time. A model describing the combined effects of the evolution of a chemical process and of spin-lattice relaxation is shown. Applied to a Diels-Alder reaction, it permitted measuring kinetics along with the effects of auto- and cross-relaxation. DNP polarization of small molecules also shows significant promise for studying protein-ligand interaction. The binding of fluorinated ligands to the protease trypsin was studied through the observation of various NMR parameter changes, such as line width, signal intensity and chemical shift of the ligands. Intermolecular polarization transfer from hyperpolarized ligand to protein can further provide information about the binding pocket of the protein. As an alternative to direct observation of protein signal, a model is presented to describe a two-step intermolecular polarization transfer between competitively binding ligands mediated through the common binding pocket of the protein. The solutions of this model relate the evolution of signal intensities to the intermolecular cross relaxation rates, which depend on individual distances in the binding epitope. In summary, DNP provides incomparable sensitivity, speed and selectivity to NMR. Quantitative models such as those discussed here enable taking full advantage of these benefits for the study of chemical processes.

Zeng, Haifeng

2012-05-01T23:59:59.000Z

58

Rotor Design for High Pressure Magic Angle Spinning Nuclear Magnetic Resonance  

Science Conference Proceedings (OSTI)

High pressure magic angle spinning (MAS) nuclear magnetic resonance (NMR) with a sample spinning rate exceeding 2.1 kHz and pressure greater than 165 bar has never been realized. In this work, a new sample cell design is reported, suitable for constructing cells of different sizes. Using a 7.5 mm high pressure MAS rotor as an example, internal pressure as high as 200 bar at a sample spinning rate of 6 kHz is achieved. The new high pressure MAS rotor is re-usable and compatible with most commercial NMR set-ups, exhibiting low 1H and 13C NMR background and offering maximal NMR sensitivity. As an example of its many possible applications, this new capability is applied to determine reaction products associated with the carbonation reaction of a natural mineral, antigorite ((Mg,Fe2+)3Si2O5(OH)4), in contact with liquid water in water-saturated supercritical CO2 (scCO2) at 150 bar and 50 ?C. This mineral is relevant to the deep geologic disposal of CO2, but its iron content results in too many sample spinning sidebands at low spinning rate. Hence, this chemical system is a good case study to demonstrate the utility of the higher sample spinning rates that can be achieved by our new rotor design. We expect this new capability will be useful for exploring solid-state, including interfacial, chemistry at new levels of high-pressure in a wide variety of fields.

Turcu, Romulus VF; Hoyt, David W.; Rosso, Kevin M.; Sears, Jesse A.; Loring, John S.; Felmy, Andrew R.; Hu, Jian Z.

2013-01-01T23:59:59.000Z

59

Three dimensional nuclear magnetic resonance spectroscopic imaging of sodium ions using stochastic excitation and oscillating gradients  

SciTech Connect

Nuclear magnetic resonance (NMR) spectroscopic imaging of {sup 23}Na holds promise as a non-invasive method of mapping Na{sup +} distributions, and for differentiating pools of Na{sup +} ions in biological tissues. However, due to NMR relaxation properties of {sup 23}Na in vivo, a large fraction of Na{sup +} is not visible with conventional NMR imaging methods. An alternate imaging method, based on stochastic excitation and oscillating gradients, has been developed which is well adapted to measuring nuclei with short T{sub 2}. Contemporary NMR imaging techniques have dead times of up to several hundred microseconds between excitation and sampling, comparable to the shortest in vivo {sup 23}Na T{sub 2} values, causing significant signal loss. An imaging strategy based on stochastic excitation has been developed which greatly reduces experiment dead time by reducing peak radiofrequency (RF) excitation power and using a novel RF circuit to speed probe recovery. Continuously oscillating gradients are used to eliminate transient eddy currents. Stochastic {sup 1}H and {sup 23}Na spectroscopic imaging experiments have been performed on a small animal system with dead times as low as 25{mu}s, permitting spectroscopic imaging with 100% visibility in vivo. As an additional benefit, the encoding time for a 32x32x32 spectroscopic image is under 30 seconds. The development and analysis of stochastic NMR imaging has been hampered by limitations of the existing phase demodulation reconstruction technique. Three dimensional imaging was impractical due to reconstruction time, and design and analysis of proposed experiments was limited by the mathematical intractability of the reconstruction method. A new reconstruction method for stochastic NMR based on Fourier interpolation has been formulated combining the advantage of a several hundredfold reduction in reconstruction time with a straightforward mathematical form.

Frederick, B.deB. [California Univ., Berkeley, CA (United States)]|[Lawrence Berkeley Lab., CA (United States)

1994-12-01T23:59:59.000Z

60

Geophysical applications of nuclear resonant spectroscopy Wolfgang Sturhahn and Jennifer M. Jackson*  

E-Print Network (OSTI)

Geophysical applications of nuclear resonant spectroscopy Wolfgang Sturhahn and Jennifer M. Jackson summarize recent developments of nuclear resonant spectroscopy methods like nuclear resonant inelastic x important information on valence, spin state, and magnetic ordering. Both methods use a nuclear resonant

Jackson, Jennifer M.

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Attainable entanglement of unitary transformed thermal states in liquid-state nuclear magnetic resonance with the chemical shift  

E-Print Network (OSTI)

Recently, Yu, Brown, and Chuang [Phys. Rev. A {\\bf 71}, 032341 (2005)] investigated the entanglement attainable from unitary transformed thermal states in liquid-state nuclear magnetic resonance (NMR). Their research gave an insight into the role of the entanglement in a liquid-state NMR quantum computer. Moreover, they attempted to reveal the role of mixed-state entanglement in quantum computing. However, they assumed that the Zeeman energy of each nuclear spin which corresponds to a qubit takes a common value for all; there is no chemical shift. In this paper, we research a model with the chemical shifts and analytically derive the physical parameter region where unitary transformed thermal states are entangled, by the positive partial transposition (PPT) criterion with respect to any bipartition. We examine the effect of the chemical shifts on the boundary between the separability and the nonseparability, and find it is negligible.

Yukihiro Ota; Shuji Mikami; Motoyuki Yoshida; Ichiro Ohba

2006-12-19T23:59:59.000Z

62

Advanced characterization of physical properties of coals with different coal structures by nuclear magnetic resonance and X-ray computed tomography  

Science Conference Proceedings (OSTI)

In order to understand the correlation between coal structure and physical property of coal, samples with different coal structures were collected from the Late Permian period coal seams in the Laochang area, Yunnan Province, China. A set of experiments ... Keywords: Adsorption capacities, Coal structure, Nuclear magnetic resonance (NMR), Seepage capacities, X-ray computed tomography (X-CT)

Song Li; Dazhen Tang; Hao Xu; Zi Yang

2012-11-01T23:59:59.000Z

63

Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects  

E-Print Network (OSTI)

263 5.2 Nuclear and atomic265 5.2.1 Thermal equilibrium nuclearatomic magnetometer used for detecting Xe-129 nuclear magne-

Urban, Jeffry Todd

2004-01-01T23:59:59.000Z

64

A nuclear magnetic resonance probe of Fe-Al and Al20V2Eu intermetallics  

E-Print Network (OSTI)

Al-rich Fe-Al systems (FeAl2, Fe2 Al5 and Fe4Al13) and Al20V2Eu have complicated structures with quasicrystal-like features making these materials potentially of interest for magnetic behavior. However, there is not much work on these materials. To study the variety of magnetic properties, we use NMR, magnetic susceptibility, specific heat and other methods in this work. The microscopic electronic and magnetic properties of the Al-rich Fe-Al system and Al20V2Eu have been studied via 27Al NMR at temperatures between 4 and 500 K. The results of spin lattice relaxation rates reveal a pseudogap in Fe4Al13 and Fe2Al5 around the Fermi-level in the density of states. Besides, a square well gap with a width of 2 meV and center at Fermi energy was detected by specific heat measurements in Fe2Al5. Both Fe4 Al13 and Fe2Al5 are non-magnetic systems with dilute magnetic defects, while FeAl2 is a concentrated local magnetic moment system. In Al20V2Eu, a crossover was observed in NMR, magnetization and transport measurements. Above 40 K, Eu(2+) local magnetic moments dominate; below 40 K, a transition to a Kondo regime is observed, where the Kondo effect leads to the reduction of localized moments due to the formation of a spin-compensated Kondo cloud. With increasing magnetic field, f electrons participate more and more in excitations near the Fermi level and a heavy-Fermion state was observed through specific heat measurements at high magnetic field.

Chi, Ji

2007-08-01T23:59:59.000Z

65

Nuclear Resonance Fluorescence for Materials Assay  

E-Print Network (OSTI)

et al. Investigation of Nuclear Structure by Resonance1996, pp. G. Warren et al. Nuclear Resonance Fluorescenceof 235U IEEE Nuclear Science Symposium 2006, pp. 914. W.

Quiter, Brian J.

2010-01-01T23:59:59.000Z

66

Nuclear Resonance Fluorescence for Materials Assay  

E-Print Network (OSTI)

clandestine material with nuclear resonance fluorescence.E. Norman, UC Berkeley Dept. of Nuclear Engineering, privatepp. 349. G. Warren et al. Nuclear Resonance Fluorescence of

Quiter, Brian

2010-01-01T23:59:59.000Z

67

Nuclear Magnetic Resonance Investigation of Dynamics in Poly(Ethylene Oxide) Based Lithium Polyether-ester-sulfonate Ionomers  

SciTech Connect

Nuclear magnetic resonance (NMR) spectroscopy has been utilized to investigate the dynamics of poly(ethylene oxide)-based lithium sulfonate ionomer samples that have low glass transition temperatures. 1H and 7Li spin-lattice relaxation times (T1) of the bulk polymer and lithium ions, respectively, were analyzed in samples with a range of ion contents. The temperature dependence of T1 values along with the presence of minima in T1 enabled correlation times and activation energies to be obtained for both the segmental motion of the polymer backbone and the hopping motion of lithium cations. Similar activation energies of both the polymer and lithium ions in the lower ion content samples indicate that the polymer segmental motion and lithium ion hopping motion are correlated even though their respective correlation times differ significantly. A divergent trend is observed for correlation times and activation energies of the highest ion content sample due to the presence of ionic aggregation. Details about the polymer and cation dynamics on the nanosecond timescale are discussed and complement the findings of X-ray scattering and Quasi Elastic Neutron Scattering experiments.

Roach, David J.; Dou, Shichen; Colby, Ralph H.; Mueller, Karl T.

2012-01-07T23:59:59.000Z

68

Nuclear magnetic resonance measurements reveal the origin of the Debye process in monohydroxy alcohols  

E-Print Network (OSTI)

Monohydroxy alcohols show a structural relaxation and at longer time scales a Debye-type dielectric peak. From spin-lattice relaxation experiments using different nuclear probes an intermediate, slower-than-structural dynamics is identified for n-butanol. Based on these findings and on diffusion measurements, a model of self-restructuring, transient chains is proposed. The model is demonstrated to explain consistently the so far puzzling observations made for this class of hydrogen-bonded glass forming liquids.

C. Gainaru; R. Meier; S. Schildmann; C. Lederle; W. Hiller; E. A. Rssler; R. Bhmer

2010-08-19T23:59:59.000Z

69

Low field magnetic resonance imaging  

DOE Patents (OSTI)

A method and system of magnetic resonance imaging does not need a large homogenous field to truncate a gradient field. Spatial information is encoded into the spin magnetization by allowing the magnetization to evolve in a non-truncated gradient field and inducing a set of 180 degree rotations prior to signal acquisition.

Pines, Alexander (Berkeley, CA); Sakellariou, Dimitrios (Billancourt, FR); Meriles, Carlos A. (Fort Lee, NJ); Trabesinger, Andreas H. (London, GB)

2010-07-13T23:59:59.000Z

70

High Field Magnetic Resonance Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

HFMRF Overview HFMRF Overview Section 2-3-1 High Field Magnetic Resonance Facility The High Field Magnetic Resonance Facility (HFMRF) focuses a significant portion of its research on developing a fundamental, molecular-level understanding of biochemical and biological systems and their response to environmental effects. A secondary focus is materials science, including catalysis and chemical mechanisms and processes. Staff and science consultants within this facility offer expertise in the areas of structural biology, solid-state materials characterization, and magnetic resonance imaging (MRI) techniques. Research activities in the HFMRF include: * structure determination of large molecular assemblies such as protein-DNA (normal and damaged DNA) and protein-RNA complexes

71

Resolving the Impact of Biological Processes on Water Transport in Unsaturated Porous Media Through Nuclear Magnetic Resonance Micro-Imaging  

DOE Green Energy (OSTI)

The magnetic resonance microscopy (MRM) work at Montana State University has extended the imaging of a single biofilm in a 1 mm capillary reactor to correlate T2 magnetic relaxation maps displaying biofilm structure with the corresponding velocity patterns in three dimensions in a Staphylococcus epidermidis biofilm fouled square capillary. A square duct geometry is chosen to provide correlation with existing experiments and simulations, as research bioreactors tend to be of square or rectangular cross section for optical or microelectrode access. The spatially resolved velocity data provide details on the impact of biofilm induced advection on mass transport from the bulk fluid to the biofilm and through the capillary bioreactor.

Seymour, Joseph D.

2005-06-01T23:59:59.000Z

72

Nuclear Resonance Fluorescence for Nuclear Materials Assay.  

E-Print Network (OSTI)

??This dissertation examines the measurement of nuclear resonance fluorescence gamma-rays as a technique to non-destructively determine isotopic compositions of target materials that are of interest (more)

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

73

Distinguishing carbonate reservoir pore facies with nuclear magnetic resonance as an aid to identify candidates for acid stimulation  

E-Print Network (OSTI)

The determination of reservoir quality and its spatial distribution is a key objective in reservoir characterization. This is especially challenging for carbonates because, due to the effects of diagenesis, quality rarely follows depositional patterns. This study integrates data from thin sections and core analyses with measurements of Nuclear Magnetic Resonance (NMR) T2 relaxation times. It exposes a novel approach to the use of NMR by applying geological and statistical analysis to define relationships between pore characteristics and the T2 data, from which a method to identify pore origin from NMR only is developed. One hundred and three samples taken from eleven wells located in fields of the Middle East, Alabama and Texas were used in the study. Modeling of the T2 spectra, as the sum of three normal components, resulted in the definition of 9 parameters representing the average, the variability and the percentage of total porosity of the specific pore sizes present in the sample. Each specific pore size corresponds to one of the following genetic pore types: intergranular, matrix, dissolution-enhanced, intercrystalline, vuggy and cement-reduced. Among the 9 parameters, two variables were identified as having the highest degree of geological significance that could be used to discriminate between pore categories: ?µmax which represents the largest average pore size of all pore types identified in the sample, and Ï?main which represents the size variability of the most abundant pore type. Based on the joint distribution of ?µmax and Ï?main computed for each pore category, the probability that an unclassified sample belongs to each of the pore categories, is calculated and the sample is assigned to the category with the highest probability. The accuracy of the method was investigated by comparing NMR predicted pore origin and genetic pore type described from thin section. A result of 89 successful predictions out of 103 samples was obtained. These promising results indicate that T2 time can be a useful identifier of carbonate pore types. Success in this work takes us closer to identifying genetic pore types from NMR logs with minimal calibration against borehole cores and will help predict the spatial distribution of poroperm facies in complex carbonate reservoirs with much improved accuracy.

Genty, Coralie

2006-08-01T23:59:59.000Z

74

Study of hydrogen in coals, polymers, oxides, and muscle water by nuclear magnetic resonance; extension of solid-state high-resolution techniques. [Hydrogen molybdenum bronze  

DOE Green Energy (OSTI)

Nuclear magnetic resonance (NMR) spectroscopy has been an important analytical and physical research tool for several decades. One area of NMR which has undergone considerable development in recent years is high resolution NMR of solids. In particular, high resolution solid state /sup 13/C NMR spectra exhibiting features similar to those observed in liquids are currently achievable using sophisticated pulse techniques. The work described in this thesis develops analogous methods for high resolution /sup 1/H NMR of rigid solids. Applications include characterization of hydrogen aromaticities in fossil fuels, and studies of hydrogen in oxides and bound water in muscle.

Ryan, L.M.

1981-10-01T23:59:59.000Z

75

Magnetic resonance apparatus  

SciTech Connect

Means for producing a region of homogeneous magnetic field remote from the source of the field, wherein two equal field sources are arranged axially so their fields oppose, producing a region near the plane perpendicular to the axis midway between the sources where the radial component of the field goes through a maximum. Near the maximum, the field is homogeneous over prescribed regions.

Jackson, Jasper A. (Los Alamos, NM); Cooper, Richard K. (Los Alamos, NM)

1982-01-01T23:59:59.000Z

76

Magnetic resonance apparatus  

DOE Patents (OSTI)

The patent consists of means for producing a region of homogeneous magnetic field remote from the source of the field, wherein two equal field sources are arranged axially so their fields oppose, producing a region near the plane perpendicular to the axis midway between the sources where the radial correspondent of the field goes through a maximum. Near the maximum, the field is homogeneous over prescribed regions.

Jackson, J.A.; Cooper, R.K.

1980-10-10T23:59:59.000Z

77

Magnetic Resonance Connectome Automated Pipeline  

E-Print Network (OSTI)

This manuscript presents a novel, tightly integrated pipeline for estimating a connectome, which is a comprehensive description of the neural circuits in the brain. The pipeline utilizes magnetic resonance imaging (MRI) data to produce a high-level estimate of the structural connectivity in the human brain. The Magnetic Resonance Connectome Automated Pipeline (MRCAP) is efficient and its modular construction allows researchers to modify algorithms to meet their specific requirements. The pipeline has been validated and over 200 connectomes have been processed and analyzed to date. This tool enables the prediction and assessment of various cognitive covariates, and this research is applicable to a variety of domains and applications. MRCAP will enable MR connectomes to be rapidly generated to ultimately help spur discoveries about the structure and function of the human brain.

Gray, William R; Vogelstein, Joshua T; Landman, Bennett A; Prince, Jerry L; Vogelstein, R Jacob

2011-01-01T23:59:59.000Z

78

Nondestructive Spent Fuel Assay Using Nuclear Resonance Fluorescence  

E-Print Network (OSTI)

09-01188, ANS Advances in Nuclear Fuel Management IV, Hiltonanalysis of spent nuclear fuel via nuclear resonanceNondestructive Spent Fuel Assay Using Nuclear Resonance

Quiter, Brian

2010-01-01T23:59:59.000Z

79

Magnetic Resonance Imaging at Princeton, UofV, and UNH | U.S...  

Office of Science (SC) Website

Magnetic Resonance Imaging at Princeton, UofV, and UNH Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff...

80

Abstract-In this study, imaging of electrical current density in conducting objects, which contain nuclear magnetic resonance  

E-Print Network (OSTI)

at each cycle within the object. The applied current pulse creates a measurable magnetic flux density. The component of magnetic flux density parallel to the main magnetic field accumulates an additional phase with and without the current pulse. Measurement of all three components of magnetic flux density makes

Eyüboðlu, Murat

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Spin microscope based on optically detected magnetic resonance  

DOE Patents (OSTI)

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2010-07-13T23:59:59.000Z

82

Spin microscope based on optically detected magnetic resonance  

Science Conference Proceedings (OSTI)

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2009-10-27T23:59:59.000Z

83

Spin microscope based on optically detected magnetic resonance  

SciTech Connect

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2010-06-29T23:59:59.000Z

84

Spin microscope based on optically detected magnetic resonance  

DOE Patents (OSTI)

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of impaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2009-11-10T23:59:59.000Z

85

Spin microscope based on optically detected magnetic resonance  

SciTech Connect

The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

2007-12-11T23:59:59.000Z

86

Using Nuclear Resonance Fluorescence for Nondestructive Isotopic Analysis  

E-Print Network (OSTI)

7, (1959) pp. 54. [12] B.J. Quiter, ``Nuclear ResonanceFluorescence for Nuclear Materials Assay,'' University ofclandestine material with nuclear resonance fluorescence,"

Ludewigt, Bernhard A.

2010-01-01T23:59:59.000Z

87

Wireless Energy Transfer Using Magnetic Resonance  

Science Conference Proceedings (OSTI)

In 1899, Nikola Tesla, who had devised a type of resonant transformer called the Tesla coil, achieved a major breakthrough in his work by transmitting 100 million volts of electric power wirelessly over a distance of 26 miles to light up a bank of 200 ... Keywords: wireless energy transfer, near field, evanescent wave, magnetic resonance, self-resonance

Rohan Bhutkar; Sahil Sapre

2009-12-01T23:59:59.000Z

88

Applications of Nuclear Resonance Fluorescence  

Science Conference Proceedings (OSTI)

Nuclear Resonance Fluorescence (NRF) has the potential of addressing a wide variety of applications, which require isotopic and/or elemental information about a sample. We have investigated a variety of non-proliferation applications that may be addressed by NRF. From these applications, we have selected two, measuring uranium enrichment in UF6 cylinders and material verification in dismantlement, to investigate in more detail. Analytical models have been developed to evaluate these applications, and test measurements have been conducted to validate those models. We found that it is unlikely with current technology to address the requirements for UF6 cylinder enrichment measurements. In contrast, NRF is a very promising approach for material verification for dismantlement.

Warren, Glen A.; Detwiler, Rebecca S.; Peplowski, Patrick N.

2010-11-11T23:59:59.000Z

89

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

that are of interest for nuclear security applications. Theof interest to nuclear security. To either make theseother targets of nuclear security interest, such kilogram-

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

90

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

and Diablo Canyon 2 nuclear reactors. Data were taken fromCapacity Operation of nuclear reactors for power generationby the operation of nuclear reactors. Therefore, ap-

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

91

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

Energy Transmission say for Nuclear Fuel Assemblies 4.1Facilities Spent nuclear fuel is another example wherein intact spent nuclear fuel would be a technological

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

92

Method of using a nuclear magnetic resonance spectroscopy standard. [SO/sub 2/ in gases by fluorescence  

DOE Patents (OSTI)

(CH/sub 3/)/sub 3/SiNSO is produced by the reaction of ((CH/sub 3/)/sub 3/SI)/sub 2/NH with SO/sub 2/. Also produced in the reaction are ((CH/sub 3/)/sub 3/Si)/sub 2/O and a new solid compound (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/). Both (CH/sub 3/)/sub 3/SiNSO and (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/) have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO/sub 2/ pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH/sub 3/)/sub 3/Si)/sub 2/NH, whereby any SO/sub 2/ present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO/sub 2/ in the original gas sample. The solid product (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/) may be used as a standard in solid state NMR spectroscopy, wherein the resonance peaks of either /sup 1/H, /sup 13/C, /sup 15/N, or /sup 29/Si may be used as a reference.

Spicer, L.D.; Bennett, D.W.; Davis, J.F.

1983-05-09T23:59:59.000Z

93

Inelastic X-ray and Nuclear Resonant Scattering  

NLE Websites -- All DOE Office Websites (Extended Search)

Beamlines Divisions Argonne Home > Advanced Photon Source > Inelastic X-ray and Nuclear Resonant Scattering The Inelastic X-ray and Nuclear Resonant Scattering group...

94

Toxicometabolomics approach to urinary biomarkers for mercuric chloride (HgCl{sub 2})-induced nephrotoxicity using proton nuclear magnetic resonance ({sup 1}H NMR) in rats  

Science Conference Proceedings (OSTI)

The primary objective of this study was to determine and characterize surrogate biomarkers that can predict nephrotoxicity induced by mercuric chloride (HgCl{sub 2}) using urinary proton nuclear magnetic resonance ({sup 1}H NMR) spectral data. A procedure for {sup 1}H NMR urinalysis using pattern recognition was proposed to evaluate nephrotoxicity induced by HgCl{sub 2} in Sprague-Dawley rats. HgCl{sub 2} at 0.1 or 0.75 mg/kg was administered intraperitoneally (i.p.), and urine was collected every 24 h for 6 days. Animals (n = 6 per group) were sacrificed 3 or 6 days post-dosing in order to perform clinical blood chemistry tests and histopathologic examinations. Urinary {sup 1}H NMR spectroscopy revealed apparent differential clustering between the control and HgCl{sub 2} treatment groups as evidenced by principal component analysis (PCA) and partial least square (PLS)-discriminant analysis (DA). Time- and dose-dependent separation of HgCl{sub 2}-treated animals from controls was observed by PCA of {sup 1}H NMR spectral data. In HgCl{sub 2}-treated rats, the concentrations of endogenous urinary metabolites of glucose, acetate, alanine, lactate, succinate, and ethanol were significantly increased, whereas the concentrations of 2-oxoglutarate, allantoin, citrate, formate, taurine, and hippurate were significantly decreased. These endogenous metabolites were selected as putative biomarkers for HgCl{sub 2}-induced nephrotoxicity. A dose response was observed in concentrations of lactate, acetate, succinate, and ethanol, where severe disruption of the concentrations of 2-oxoglutarate, citrate, formate, glucose, and taurine was observed at the higher dose (0.75 mg/kg) of HgCl{sub 2}. Correlation of urinary {sup 1}H NMR PLS-DA data with renal histopathologic changes suggests that {sup 1}H NMR urinalysis can be used to predict or screen for HgCl{sub 2}-induced nephrotoxicity{sub .}

Kim, Kyu-Bong, E-mail: kyubong@inje.ac.k [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of); Department of Pharmaceutical Engineering, Inje University, Obang-dong, Gimhae, Gyungnam 621-749 (Korea, Republic of); Um, So Young, E-mail: syum@kfda.go.k [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of); Chung, Myeon Woo, E-mail: mwchung@kfda.go.k [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of); Jung, Seung Chul, E-mail: ipipe4@nate.co [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of); Oh, Ji Seon, E-mail: aquajs24@nate.co [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of); Kim, Seon Hwa, E-mail: hwa2003@kfda.go.k [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of); Na, Han Sung, E-mail: nhk1515@korea.k [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of); Lee, Byung Mu, E-mail: bmlee@skku.ed [College of Pharmacy, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746 (Korea, Republic of); Choi, Ki Hwan, E-mail: hyokwa11@korea.k [Korea Food and Drug Administration, 5-Nokbun-dong, Eunpyung-gu, Seoul 122-704 (Korea, Republic of)

2010-12-01T23:59:59.000Z

95

Examining 239Pu and 240Pu Nuclear Resonance Fluorescence Measurements on Spent Fuel for Nuclear Safeguards  

E-Print Network (OSTI)

S.D. Ambers, Assesment of Nuclear Resonance Fluorescencefor Spent Nuclear Fuel Assay, Inst. of Nucl. Mat. Man. ,clandestine material with nuclear resonance fluorescence,

Quiter, Brian

2013-01-01T23:59:59.000Z

96

Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel  

E-Print Network (OSTI)

and Nuclear Recoil . . . . . . . . . . . . . . . . . . . . .2 Quantitative Measurements using NRF 2.1 Nuclear ResonanceFuture Work A Transmission Nuclear Resonance Fluorescence

Ludewigt, Bernhard A

2011-01-01T23:59:59.000Z

97

NUCLEAR RESONANT SCATTERING AT HIGH PRESSURE AND HIGH TEMPERATURE  

E-Print Network (OSTI)

NUCLEAR RESONANT SCATTERING AT HIGH PRESSURE AND HIGH TEMPERATURE JIYONG ZHAOa,? , WOLFGANG, The University of Chicago, Chicago, IL 60637, USA We introduce the combination of nuclear resonant inelastic X the thermal radiation spectra fitted to the Planck radiation function up to 1700 K. Nuclear resonant

Shen, Guoyin

98

Magnetic Resonance Imaging at Princeton, UofV, and UNH | U.S. DOE Office of  

Office of Science (SC) Website

Magnetic Resonance Imaging at Magnetic Resonance Imaging at Princeton, UofV, and UNH Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Magnetic Resonance Imaging at Princeton, UofV, and UNH Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: MRI for hyperpolarized gases Developed at: Princeton, University of Virginia, University of New Hampshire

99

Method and apparatus for measuring nuclear magnetic properties  

DOE Patents (OSTI)

A method for studying the chemical and structural characteristics of materials is disclosed. The method includes placement of a sample material in a high strength polarizing magnetic field to order the sample nuclei. The condition used to order the sample is then removed abruptly and the ordering of the sample allowed to evolve for a time interval. At the end of the time interval, the ordering of the sample is measured by conventional nuclear magnetic resonance techniques. 5 figs.

Weitekamp, D.P.; Bielecki, A.; Zax, D.B.; Zilm, K.W.; Pines, A.

1987-12-01T23:59:59.000Z

100

Magnetic resonance studies on ZnO nanocrystals  

Science Conference Proceedings (OSTI)

ZnO nanocrystals with diameters ranging from 4 to 50 nm were prepared via a wet chemical method and post-growth annealing treatments. The electron paramagnetic resonance (EPR) spectra of the nanocrystals show the resonance of electron centers with g-value ... Keywords: K ? P theory, ZnO nanocrystal, electronic paramagnetic resonance (EPR), magnetic resonance

H. Zhou; A. Hofstaetter; D. M. Hofmann; B. K. Meyer

2003-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Assessment of Nuclear Resonance Fluorescence for Spent Nuclear Fuel Assay  

SciTech Connect

In nuclear resonance fluorescence (NRF) measurements, resonances are excited by an external photon beam leading to the emission of gamma rays with specific energies that are characteristic of the emitting isotope. NRF promises the unique capability of directly quantifying a specific isotope without the need for unfolding the combined responses of several fissile isotopes as is required in other measurement techniques. We have analyzed the potential of NRF as a non-destructive analysis technique for quantitative measurements of Pu isotopes in spent nuclear fuel (SNF). Given the low concentrations of 239Pu in SNF and its small integrated NRF cross sections, the main challenge in achieving precise and accurate measurements lies in accruing sufficient counting statistics in a reasonable measurement time. Using analytical modeling, and simulations with the radiation transport code MCNPX that has been experimentally tested recently, the backscatter and transmission methods were quantitatively studied for differing photon sources and radiation detector types. Resonant photon count rates and measurement times were estimated for a range of photon source and detection parameters, which were used to determine photon source and gamma-ray detector requirements. The results indicate that systems based on a bremsstrahlung source and present detector technology are not practical for high-precision measurements of 239Pu in SNF. Measurements that achieve the desired uncertainties within hour-long measurements will either require stronger resonances, which may be expressed by other Pu isotopes, or require quasi-monoenergetic photon sources with intensities that are approximately two orders of magnitude higher than those currently being designed or proposed.This work is part of a larger effort sponsored by the Next Generation Safeguards Initiative to develop an integrated instrument, comprised of individual NDA techniques with complementary features, that is fully capable of determining Pu mass in spent fuel assemblies.

Quiter, Brian; Ludewigt, Bernhard; Ambers, Scott

2011-06-30T23:59:59.000Z

102

Nuclear resonance tomography with a toroid cavity detector  

DOE Patents (OSTI)

A toroid cavity detection system for determining the spectral properties and distance from a fixed point for a sample using Nuclear Magnetic Resonance. The detection system consists of a toroid with a central conductor oriented along the main axis of the toroidal cylinder and perpendicular to a static uniform magnetic field oriented along the main axis of the toroid. An rf signal is inputted to the central conductor to produce a magnetic field perpendicular to the central axis of the toroid and whose field strength varies as the inverse of the radius of the toroid. The toroid cavity detection system can be used to encapsulate a sample, or the detection system can be perforated to allow a sample to flow into the detection device or to place the samples in specified sample tubes. The central conductor can also be coated to determine the spectral property of the coating and the coating thickness. The sample is then subjected to the respective magnetic fields and the responses measured to determine the desired properties.

Woelk, K.; Rathke, J.W.; Klingler, R.J.

1994-12-31T23:59:59.000Z

103

Nuclear resonance tomography with a toroid cavity detector  

DOE Patents (OSTI)

A toroid cavity detection system is described for determining the spectral properties and distance from a fixed point for a sample using Nuclear Magnetic Resonance. The detection system consists of a toroid with a central conductor oriented along the main axis of the toroidal cylinder and perpendicular to a static uniform magnetic field oriented along the main axis of the toroid. An rf signal is input to the central conductor to produce a magnetic field perpendicular to the central axis of the toroid and whose field strength varies as the inverse of the radius of the toroid. The toroid cavity detection system can be used to encapsulate a sample, or the detection system can be perforated to allow a sample to flow into the detection device or to place the samples in specified sample tubes. The central conductor can also be coated to determine the spectral property of the coating and the coating thickness. The sample is then subjected to the respective magnetic fields and the responses measured to determine the desired properties. 4 figs.

Woelk, K.; Rathke, J.W.; Klingler, R.J.

1996-11-12T23:59:59.000Z

104

Nuclear Resonance Fluorescence for Safeguards Applications  

SciTech Connect

In nuclear resonance fluorescence (NRF) measurements, resonances are excited by an external photon beam leading to the emission of {gamma} rays with specific energies that are characteristic of the emitting isotope. The promise of NRF as a non-destructive analysis technique (NDA) in safeguards applications lies in its potential to directly quantify a specific isotope in an assay target without the need for unfolding the combined responses of several fissile isotopes as often required by other NDA methods. The use of NRF for detection of sensitive nuclear materials and other contraband has been researched in the past. In the safeguards applications considered here one has to go beyond mere detection and precisely quantify the isotopic content, a challenge that is discussed throughout this report. Basic NRF measurement methods, instrumentation, and the analytical calculation of NRF signal strengths are described in Section 2. Well understood modeling and simulation tools are needed for assessing the potential of NRF for safeguards and for designing measurement systems. All our simulations were performed with the radiation transport code MCNPX, a code that is widely used in the safeguards community. Our initial studies showed that MCNPX grossly underestimated the elastically scattered background at backwards angles due to an incorrect treatment of Rayleigh scattering. While new, corrected calculations based on ENDF form factors showed much better agreement with experimental data for the elastic scattering of photons on an uranium target, the elastic backscatter is still not rigorously treated. Photonuclear scattering processes (nuclear Thomson, Delbruck and Giant Dipole Resonance scattering), which are expected to play an important role at higher energies, are not yet included. These missing elastic scattering contributions were studied and their importance evaluated evaluated against data found in the literature as discussed in Section 3. A transmission experiment was performed in September 2009 to test and demonstrate the applicability of the method to the quantitative measurement of an isotope of interest embedded in a thick target. The experiment, data analysis, and results are described in Section 4. The broad goal of our NRF studies is to assess the potential of the technique in safeguards applications. Three examples are analyzed in Section 5: the isotopic assay of spent nuclear fuel (SNF), the measurement of {sup 235}U enrichment in UF{sub 6} cylinders, and the determination of {sup 239}Pu in mixed oxide (MOX) fuel. The study of NRF for the assay of SNF assemblies was supported by the Next Generation Safeguards Initiative (NGSI) of the U.S. Department of Energy as part of a large multi-lab/university effort to quantify the plutonium (Pu) mass in spent nuclear fuel assemblies and to detect the diversion of pins with non-destructive assay (NDA) methods. NRF is one of 14 NDA techniques being researched. The methodology for performing and analyzing quantitative NRF measurements was developed for determining Pu mass in SNF and is extensively discussed in this report. The same methodology was applied to the assessment of NRF for the measurement of {sup 235}U enrichment and the determination of {sup 239}Pu in MOX fuel. The analysis centers on determining suitable NRF measurement methods, measurement capabilities that could be realized with currently available instrumentation, and photon source and detector requirements for achieving useful NDA capabilities.

Ludewigt, Bernhard A; Quiter, Brian J; Ambers, Scott D

2011-02-04T23:59:59.000Z

105

Coal liquefaction process streams characterization and evaluation. Characterization of coal-derived materials by field desorption mass spectrometry, two-dimensional nuclear magnetic resonance, supercritical fluid extraction, and supercritical fluid chromatography/mass spectrometry  

SciTech Connect

Under contract from the DOE , and in association with CONSOL Inc., Battelle, Pacific Northwest Laboratory (PNL) evaluated four principal and several complementary techniques for the analysis of non-distillable direct coal liquefaction materials in support of process development. Field desorption mass spectrometry (FDMS) and nuclear magnetic resonance (NMR) spectroscopic methods were examined for potential usefulness as techniques to elucidate the chemical structure of residual (nondistillable) direct coal liquefaction derived materials. Supercritical fluid extraction (SFE) and supercritical fluid chromatography/mass spectrometry (SFC/MS) were evaluated for effectiveness in compound-class separation and identification of residual materials. Liquid chromatography (including microcolumn) separation techniques, gas chromatography/mass spectrometry (GC/MS), mass spectrometry/mass spectrometry (MS/MS), and GC/Fourier transform infrared (FTIR) spectroscopy methods were applied to supercritical fluid extracts. The full report authored by the PNL researchers is presented here. The following assessment briefly highlights the major findings of the project, and evaluates the potential of the methods for application to coal liquefaction materials. These results will be incorporated by CONSOL into a general overview of the application of novel analytical techniques to coal-derived materials at the conclusion of CONSOL`s contract.

Campbell, J.A.; Linehan, J.C.; Robins, W.H. [Battelle Pacific Northwest Lab., Richland, WA (United States)

1992-07-01T23:59:59.000Z

106

Influence of external magnetic and laser radiation fields on Feshbach resonances in collision of atoms  

E-Print Network (OSTI)

We study collision of two atoms with formation of Feshbach resonance at combined interaction with the external magnetic field and laser radiation. In cases of one- and two-photon resonances of laser radiation with two discrete vibrational molecular levels, we show that Feshbach resonances appear at interaction of external magnetic field with dressed states formed via Autler-Townes effect. In addition, in case of one-photon resonance the lower vibrational molecular state is coupled by laser radiation with the continuum of the elastic channel and forms laser-induced Feshbach resonance via both Autler-Townes effect and LICS mechanism. We study the combined process of formation of Feshbach resonances; this enables the control of Feshbach resonance by varying the magnetic field and intensity and frequency of laser radiation. We obtain the cross-sections of elastic and inelastic scattering and show that quenching of resonance occurs at the energy equal to that of the systems ground state. Dependence of the cross-sections on the magnetic field and laser intensity is examined in detail. In all considered cases, the scattering length is obtained depending on the magnetic and laser fields are studied. In the absence of magnetic interaction if the hyperfine substates of the quasibound state in the closed channel and those of individual colliding atoms in the open channel are the same, Feshbach resonances may arise via weak interaction between nuclear and electronic motions, which leads to transitions between electronic states. The obtained results can be employed in new studies of collisions of cold atoms, e.g., of alkali metal atoms and for interpretation of new experiments in BECs.

E. A. Gazazyan; A. D. Gazazyan; V. O. Chaltykyan

2012-09-21T23:59:59.000Z

107

2-3 High Field Magnetic Resonance Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

HFMRF Overview HFMRF Overview High Field Magnetic Resonance Facility A significant portion of research conducted in the High Field Magnetic Resonance Facility (HFMRF) focuses on developing a fundamental, molecular-level understanding of biochemi- cal and biological systems and their response to environmental effects. A secondary focus is in materials science and catalysis and the chemical mechanisms and processes that operate in these areas. Resident and matrixed research staff within this facility offer expertise in the areas of structural biology, solid-state materials characterization, and magnetic resonance imaging (MRI) techniques. Instrumentation & Capabilities NMR * 900-MHz NMR (operational in 2004) * 800-MHz NMR * 750-MHz NMR * 600-MHz NMR (2 systems)

108

Investigation of Mechanical Activation on Li-N-H Systems Using 6Li Magic Angle Spinning Nuclear Magnetic Resonance at Ultra-High Field  

SciTech Connect

Abstract The significantly enhanced spectral resolution in the 6Li MAS NMR spectra of Li-N-H systems at ultra-high field of 21.1 tesla is exploited, for the first time, to study the detailed electronic and chemical environmental changes associated with mechanical activation of Li-N-H system using high energy balling milling. Complementary to ultra-high field studies, the hydrogen discharge dynamics are investigated using variable temperature in situ 1H MAS NMR at 7.05 tesla field. The significantly enhanced spectral resolution using ultra-high filed of 21.1 tesla was demonstrated along with several major findings related to mechanical activation, including the upfield shift of the resonances in 6Li MAS spectra induced by ball milling, more efficient mechanical activation with ball milling at liquid nitrogen temperature than with ball milling at room temperature, and greatly enhanced hydrogen discharge exhibited by the liquid nitrogen ball milled samples.

Hu, Jian Zhi; Kwak, Ja Hun; Yang, Zhenguo; Osborn, William; Markmaitree, Tippawan; Shaw, Leonard D.

2008-07-15T23:59:59.000Z

109

Nuclear Resonance Fluorescence for Materials Assay  

E-Print Network (OSTI)

screening of cargo for nuclear weapons materials [2],[3].peaceful nuclear activities are not diverted to weapons

Quiter, Brian J.

2010-01-01T23:59:59.000Z

110

Assessment of Nuclear Resonance Fluorescence for Spent Nuclear Fuel Assay  

E-Print Network (OSTI)

Security of the National Nuclear Security Administration, USof Energys National Nuclear Security Administration (NNSA)

Quiter, Brian

2012-01-01T23:59:59.000Z

111

Assessment of Nuclear Resonance Fluorescence for Spent Nuclear Fuel Assay  

E-Print Network (OSTI)

the National Nuclear Security Administration, US Departmentof Energys National Nuclear Security Administration (NNSA)

Quiter, Brian

2012-01-01T23:59:59.000Z

112

Examining 239Pu and 240Pu Nuclear Resonance Fluorescence Measurements on Spent Fuel for Nuclear Safeguards  

E-Print Network (OSTI)

resonance fluorescence in 240 Pu, Submitted to Phys. Rev.near 2 MeV in 235 U and 239 Pu, Phys. Rev. C 041601(R) (Examining Pu and Pu Nuclear Resonance Fluorescence

Quiter, Brian

2013-01-01T23:59:59.000Z

113

Imaging agents for in vivo magnetic resonance and scintigraphic imaging  

DOE Patents (OSTI)

Methods are provided for in vivo magnetic resonance imaging and/or scintigraphic imaging of a subject using chelated transition metal and lanthanide metal complexes. Novel ligands for these complexes are provided.

Engelstad, Barry L. (Orinda, CA); Raymond, Kenneth N. (Berkeley, CA); Huberty, John P. (Corte Madera, CA); White, David L. (Oakland, CA)

1991-01-01T23:59:59.000Z

114

Target-specific contrast agents for magnetic resonance microscopy  

E-Print Network (OSTI)

High-resolution ex vivo magnetic resonance microscopy (MRM) can be used to delineate prominent architectonic features in the human brain, but increased contrast is required to visualize more subtle distinctions. The goal ...

Hepler Blackwell, Megan Leticia

2007-01-01T23:59:59.000Z

115

Imaging agents for in vivo magnetic resonance and scintigraphic imaging  

DOE Patents (OSTI)

Methods are provided for in vivo magnetic resonance imaging and/or scintigraphic imaging of a subject using chelated transition metal and lanthanide metal complexes. Novel ligands for these complexes are provided. No Drawings

Engelstad, B.L.; Raymond, K.N.; Huberty, J.P.; White, D.L.

1991-04-23T23:59:59.000Z

116

Nuclear Resonance Fluorescence for Materials Assay  

E-Print Network (OSTI)

and safeguards for nuclear fuel cycles Examples of age-PECIFIC E XAMPLES A. Spent Nuclear Fuel A critical componentnuclear safeguards including measuring uranium enrichments, spent fuel

Quiter, Brian J.

2010-01-01T23:59:59.000Z

117

Assessment of Nuclear Resonance Fluorescence for Spent Nuclear Fuel Assay  

E-Print Network (OSTI)

of the Institute of Nuclear Material Management, Tucson, AZ,Assay, Institute of Nuclear Materials Management 51st Annual

Quiter, Brian

2012-01-01T23:59:59.000Z

118

Assessment of Nuclear Resonance Fluorescence for Spent Nuclear Fuel Assay  

E-Print Network (OSTI)

Fluorescence for Spent Nuclear Fuel Assay Brian J. Quiter ?of Pu isotopes in spent nuclear fuel (SNF). Given the lowU and 239 Pu in spent nuclear fuel using NRF. II. PERFORMING

Quiter, Brian

2012-01-01T23:59:59.000Z

119

Method for nuclear magnetic resonance imaging  

DOE Patents (OSTI)

A method for in vivo NMR imaging of the blood vessels and organs of a patient characterized by using a dark dye-like imaging substance consisting essentially of a stable, high-purity concentration of D/sub 2/O in a solution with water.

Kehayias, J.J.; Joel, D.D.; Adams, W.H.; Stein, H.L.

1988-05-26T23:59:59.000Z

120

Fissile and Non-Fissile Material Detection Using Nuclear Acoustic Resonance Signatures  

Science Conference Proceedings (OSTI)

The objective of this project is to develop anovel technique for remote, non-destructive, non-radiation-based detection of materials of interest to Nonproliferation Programs. We propse the development of a detection system based on magnetic resonance principles (NAR), which would work where radiation detection is not possible. The approach would be non-intrusive, penetrating, applicable to many materials of interest for Nonproliferation, and be able to identify the nuclear samples under investigation.

Bernhard R. Tittmann; P.M. Lenahan; David Spears; Rhys Williams

2008-11-25T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Nuclear Resonant Scattering on Earth Materials using Synchrotron Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

NRS2005 Home NRS2005 Home Agenda Organizing Committee Nuclear Resonant Scattering on Earth Materials using Synchrotron Radiation February 12-13, 2005 Advanced Photon Source Argonne National Laboratory - Argonne, Illinois, USA Nuclear Resonant Scattering (NRS) techniques provide the Earth and planetary science community with opportunities for new and exciting results on the properties of materials at high pressure and temperature conditions. Such NRS experiments have become possible due to the extreme brightness of third-generation synchrotron radiation sources. NRS techniques fall into two broad areas, which are in many ways ideally or even uniquely suited for addressing a number of important geophysical questions: Nuclear Resonant Inelastic X-ray Scattering (NRIXS) provides information on

122

A quantum description of radiation damping and the free induction signal in magnetic resonance  

Science Conference Proceedings (OSTI)

We apply the methods of cavity quantum electrodynamics (CQED), to obtain a microscopic and fully quantum-mechanical picture of radiation damping in magnetic resonance, and the nascent formation of the free induction signal. Numerical solution of the Tavis-Cummings model - i.e., multiple spins 1/2 coupled to a lossless single-mode cavity - shows in fine detail the transfer of Zeeman energy, via spin coherence, to excite the cavity - represented here by a quantized LC resonator. The case of a single spin is also solved analytically. Although the motion of the Bloch vector is non-classical, we nonetheless show that the quantum mechanical Rabi nutation frequency (as enhanced by cavity coupling and stimulated emission) gives realistic estimates of macroscopic signal strength and the radiation damping constant in nuclear magnetic resonance. We also show how to introduce dissipation: cavity losses by means of a master equation, and relaxation by the phenomenological method of Bloch. The failure to obtain the full Bloch equations (unless semi-classical conditions are imposed on the cavity) is discussed in light of similar issues arising in CQED (and in earlier work in magnetic resonance as well), as are certain problems relative to quantization of the electromagnetic near-field.

Tropp, James [General Electric Healthcare Technologies, 47697 Westinghouse Drive, Fremont, California 94539 (United States)

2013-07-07T23:59:59.000Z

123

Fundamental investigations of supported monometallic and bimetallic catalysts by proton magnetic resonance spectroscopy  

DOE Green Energy (OSTI)

Proton magnetic resonance spectroscopy, or nuclear magnetic resonance (NMR) of hydrogen, has been applied to investigate silica-supported Group VIII monometallic and Group VIII-Group IB bimetallic catalysts and alumina- and silica-supported platinum-rhenium bimetallic catalysts. Two adsorbed states of hydrogen, i.e., irreversible and reversible hydrogen, on the surfaces of monometallic Ru, Pt, and Cu particles and bimetallic Ru-Group Ib, Pt-Group Ib, and Pt-Re particles were observed directly via proton NMR. The same amounts of the irreversible hydrogen adsorbed on pure Ru catalysts were measured by both proton NMR and the volumetric technique. The electronic environments on surfaces of monometallic catalysts are sensitive to changes in metal dispersion, state of adsorbed hydrogen, and residual chlorine. Surface compositions for the Ru--Cu and Pt--Cu bimetallic catalysts were determined by NMR of adsorbed hydrogen. 297 refs., 96 figs., 19 tabs.

Wu, Xi.

1990-09-21T23:59:59.000Z

124

Methyl quantum tunneling and nitrogen-14 NQR NMR studies using a SQUID magnetic resonance spectrometer  

Science Conference Proceedings (OSTI)

Nuclear Magnetic Resonance (NMR) and Nuclear Quadrupole Resonance (NQR) techniques have been very successful in obtaining molecular conformation and dynamics information. Unfortunately, standard NMR and NQR spectrometers are unable to adequately detect resonances below a few megahertz due to the frequency dependent sensitivity of their Faraday coil detectors. For this reason a new spectrometer with a dc SQUID (Superconducting Quantum Interference Device) detector, which has no such frequency dependence, has been developed. Previously, this spectrometer was used to observe {sup 11}B and {sup 27}Al NQR resonances. The scope of this study was increased to include {sup 23}Na, {sup 51}V, and {sup 55}Mn NQR transitions. Also, a technique was presented to observe {sup 14}N NQR resonances through cross relaxation of the nitrogen polarization to adjacent proton spins. When the proton Zeeman splitting matches one nitrogen quadrupoler transition the remaining two {sup 14}N transitions can be detected by sweeping a saturating rf field through resonance. Additionally, simultaneous excitation of two nitrogen resonances provides signal enhancement which helps to connect transitions from the same site. In this way, nitrogen-14 resonances were observed in several amino acids and polypeptides. This spectrometer has also been useful in the direct detection of methyl quantum tunneling splittings at 4.2 K. Tunneling, frequencies of a homologous series of carboxylic acids were measured and for solids with equivalent crystal structures, an exponential correlation between the tunneling frequency and the enthalpy of fusion is observed. This correlation provides information about the contribution of intermolecular interactions to the energy barrier for methyl rotation.

Black, B.E. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States)

1993-07-01T23:59:59.000Z

125

Optically Detected Magnetic Resonance Studies on ?-conjugated semiconductor systems  

Science Conference Proceedings (OSTI)

Optically Detected Magnetic Resonance (ODMR) techniques were used to investigate the dynamics of excitons and charge carriers in ?-conjugated organic semiconductors. Degradation behavior of the negative spin-1/2 electroluminescence-detected magnetic resonance (ELDMR) was observed in Alq3 devices. The increase in the resonance amplitude implies an increasing bipolaron formation during degradation, which might be the result of growth of charge traps in the device. The same behavior of the negative spin-1/2 ELDMR was observed in 2wt% Rubrene doped Tris(8-hydroxyquinolinato)aluminium (Alq3) devices. However, with increasing injection current, a positive spin-1/2 ELDMR, together with positive spin 1 triplet powder patterns at {delta}m{sub S}={+-}1 and {delta}m{sub S}={+-}2, emerges. Due to the similarities in the frequency dependences of single and double modulated ELDMR and the photoluminescence-detected magnetic resonance (PLDMR) results in poly[2-methoxy-5-(2 -ethyl-hexyloxy)-1,4-phenyl ene vinylene] (MEH-PPV) films, the mechanism for this positive spin-1/2 ELDMR was assigned to enhanced triplet-polaron quenching under resonance conditions. The ELDMR in rubrene doped Alq3 devices provides a path to investigate charge distribution in the device under operational conditions. Combining the results of several devices with different carrier blocking properties and the results from transient EL, it was concluded trions not only exist near buffer layer but also exist in the electron transport layer. This TPQ model can also be used to explain the positive spin-1/2 PLDMR in poly(3-hexylthiophene) (P3HT) films at low temperature and in MEH-PPV films at various temperatures up to room temperature. Through quantitative analysis, TE-polaron quenching (TPQ) model is shown having the ability to explain most behaviors of the positive spin-1/2 resonance. Photocurrent detected magnetic resonance (PCDMR) studies on MEH-PPV devices revealed a novel transient resonance signal. The signal may originate from the higher concentration of deep traps near cathode. A quantitative analysis based on this assumption was carried out and found to be consistent with the experimental results.

Chen, Ying

2011-12-06T23:59:59.000Z

126

Hard and elastic amorphous carbon nitride thin films studied by 13 C nuclear magnetic  

E-Print Network (OSTI)

Hard and elastic amorphous carbon nitride thin films studied by 13 C nuclear magnetic resonance bonding of hard and elastic amorphous carbon nitride (a-CNx) thin films was examined using solid-state 13 on Si 001 substrates at 300 °C. Nanoindentation tests reveal a recovery of 80%, a hardness of 5 GPa

Reilly, Anne

127

Nuclear magnetic flowmeter -- Spectrometer with fiber -optical communication line in cooling systems of atomic energy plants  

Science Conference Proceedings (OSTI)

Fiber-optic communication line for transmitting a signal of nuclear magnetic resonance of liquid medium in the ship's central computer was developed. This fiber-optic communication line allows us to give an NMR signal in digital or analog form without ... Keywords: FOCL transmission coefficient, Fiber optic communication line (FOCL), communication system, optical converter, optical modulator

V. V. Davydov; V. I. Dudkin; A. U. Karseev

2013-04-01T23:59:59.000Z

128

Magnetic nuclear core restraint and control  

DOE Patents (OSTI)

A lateral restraint and control system for a nuclear reactor core adaptable to provide an inherent decrease of core reactivity in response to abnormally high reactor coolant fluid temperatures. An electromagnet is associated with structure for radially compressing the core during normal reactor conditions. A portion of the structures forming a magnetic circuit are composed of ferromagnetic material having a curie temperature corresponding to a selected coolant fluid temperature. Upon a selected signal, or inherently upon a preselected rise in coolant temperature, the magnetic force is decreased a given amount sufficient to relieve the compression force so as to allow core radial expansion. The expanded core configuration provides a decreased reactivity, tending to shut down the nuclear reaction.

Cooper, Martin H. (Monroeville, PA)

1979-01-01T23:59:59.000Z

129

Nuclear magnetic moments and related sum rules  

SciTech Connect

We first review the history and our present understanding of nuclear magnetic moments and Gamow-Teller transitions, with emphasis on the roles of configuration mixing and meson exchange currents. Then we discuss the renormalization of the orbital g-factor in nuclei, and its relation to the E1 sum rule for photoabsorption and the M1 sum rule for the scissors mode of deformed nuclei.

Bentz, Wolfgang [Department of Physics, School of Science, Tokai University, Hiratsuka-shi, Kanagawa 259-1292 (Japan); Arima, Akito [Musashi University, 1-26-1 Toyotama-kami, Nerima-ku, Tokyo 176-8534 (Japan)

2011-05-06T23:59:59.000Z

130

Allan Cormack, Computerized Axial Tomography (CAT), and Magnetic Resonance  

NLE Websites -- All DOE Office Websites (Extended Search)

Allan M. Cormack, Computerized Axial Tomography (CAT) Allan M. Cormack, Computerized Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI) Resources with Additional Information magnetic resonance imaging system Computed axial tomography, commonly known as CAT scanning, was introduced in 1972. During a CAT scan, a large coil of x-ray tubes rotates around the patient's body, taking x-rays from all angles. A computer integrates all of these x-rays into a single, three-dimensional image on a television screen. The data can be saved on the computer. Allan M. Cormack, a high energy physicist at Tufts University, shared the 1979 Nobel Prize in Physiology and Medicine for his key work in developing the methods for CAT scanners. At the time of development, these methods were widely regarded as the most significant advance in medical radiography since the 1895 discovery of x-rays.

131

Stochastic resonance in a periodically modulated dissipative nuclear dynamics  

SciTech Connect

A fission decay of highly excited periodically driven compound nuclei is considered in the framework of Langevin approach. The authors have used residual-time distribution (RTD) as the tool for studying of dynamic features in a presence of periodic perturbation. The structure of RTD essentially depends on the relation between Kramers decay rate and the frequency {omega} of the periodic perturbation. In particular, intensity of the first peak in RTD has a sharp maximum at certain nuclear temperature depending on {omega}. This maximum should be considered as first-hand manifestation of stochastic resonance in nuclear dynamics.

Berezovoy, V.P. [and others

2001-02-01T23:59:59.000Z

132

Stochastic Resonance in a Periodically Modulated Dissipative Nuclear Dynamics  

E-Print Network (OSTI)

A fission decay of highly excited periodically driven compound nuclei is considered in the framework of Langevin approach. We have used residual-time distribution (RTD) as the tool for studying of dynamic features in a presence of periodic perturbation. The structure of RTD essentially depends on the relation between Kramers decay rate and the frequency ? of the periodic perturbation. In particular, intensity of the first peak in RTD has a sharp maximum at certain nuclear temperature depending on ?. This maximum should be considered as first-hand manifestation of stochastic resonance in nuclear dynamics. 1

unknown authors

2008-01-01T23:59:59.000Z

133

Stochastic Resonance in a Periodically Modulated Dissipative Nuclear Dynamics  

E-Print Network (OSTI)

A fission decay of highly excited periodically driven compound nuclei is considered in the framework of Langevin approach. We have used residual-time distribution (RTD) as the tool for studying of dynamic features in a presence of periodic perturbation. The structure of RTD essentially depends on the relation between Kramers decay rate and the frequency of the periodic perturbation. In particular, intensity of the first peak in RTD has a sharp maximum at certain nuclear temperature depending on the frequency of the periodic perturbation. This maximum should be considered as first-hand manifestation of stochastic resonance in nuclear dynamics.

V. P. Berezovoj; Yu. L. Bolotin; O. P. Dzyubak; V. V. Yanovsky; A. V. Zhiglo

2001-01-22T23:59:59.000Z

134

Methods for magnetic resonance analysis using magic angle technique  

DOE Patents (OSTI)

Methods of performing a magnetic resonance analysis of a biological object are disclosed that include placing the object in a main magnetic field (that has a static field direction) and in a radio frequency field; rotating the object at a frequency of less than about 100 Hz around an axis positioned at an angle of about 54.degree.44' relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a phase-corrected magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. In particular embodiments the method includes pulsing the radio frequency to provide at least two of a spatially selective read pulse, a spatially selective phase pulse, and a spatially selective storage pulse. Further disclosed methods provide pulse sequences that provide extended imaging capabilities, such as chemical shift imaging or multiple-voxel data acquisition.

Hu, Jian Zhi (Richland, WA); Wind, Robert A. (Kennewick, WA); Minard, Kevin R. (Kennewick, WA); Majors, Paul D. (Kennewick, WA)

2011-11-22T23:59:59.000Z

135

Magnetic motion capture system using LC resonant magnetic marker composed of Ni-Zn ferrite core  

SciTech Connect

We have proposed a magnetic motion capture system using an LC resonant magnetic marker. The proposed system is composed of an exciting coil, an LC marker, and a 5x5-matrix search coil array (25 search coils). The LC marker is small and has a minimal circuit with no battery and can be driven wirelessly by the action of electromagnetic induction. It consists of a Ni-Zn ferrite core (3 mm{phi}x10 mm) with a wound coil and a chip capacitor, forming an LC series circuit with a resonant frequency of 186 kHz. The relative position accuracy of the system is less than 1 mm within the area of 100 mm{sup 3} up to 150 mm from the search coil array. Compared with dc magnetic systems, the proposed system is applicable for precision motion capture in optically isolated spaces without magnetic shielding because the system is not greatly influenced by earth field noise.

Hashi, S.; Toyoda, M.; Ohya, M.; Okazaki, Y.; Yabukami, S.; Ishiyama, K.; Arai, K. I. [Department of Materials Science and Technology, Gifu University, 1-1 Yanagido, Gifu 501-1193 (Japan); Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

2006-04-15T23:59:59.000Z

136

Nuclear Magnetism and Electronic Order in 13 C Nanotubes  

E-Print Network (OSTI)

Nuclear Magnetism and Electronic Order in 13 C Nanotubes Bernd Braunecker,1 Pascal Simon,1 on nuclear magnetism in one dimension. If the electrons are in the metallic, Luttinger liquid regime, we show that even a very weak hyperfine coupling to the 13C nuclear spins has a striking effect: The system

Braunecker, Bernd

137

Novel Detection Schemes of Nuclear Magnetic Resonance and Magnetic ...  

of peaks through a network of coupled spins. The power of NMR is in its ability to ... a signi?cant loss in sensitivity due to the very small volume of analyte on ...

138

Nuclear resonance scattering of synchrotron radiation as a unique electronic, structural and thermodynamic probe  

SciTech Connect

Discovery of Moessbauer effect in a nuclear transition was a remarkable development. It revealed how long-lived nuclear states with relatively low energies in the kiloelectron volt (keV) region can be excited without recoil. This new effect had a unique feature involving a coupling between nuclear physics and solid-state physics, both in terms of physics and sociology. Physics coupling originates from the fact that recoilless emission and absorption or resonance is only possible if the requirement that nuclei have to be bound in a lattice with quantized vibrational states is fulfilled, and that the finite electron density on the nucleus couples to nuclear degrees of freedom leading to hyperfine interactions. thus, Moessbauer spectroscopy allows peering into solid-state effects using unique nuclear transitions. Sociological aspects of this coupling had been equally startling and fruitful. The interaction between diverse scientific communities, who learned to use Moessbauer spectroscopy proved to be very valuable. For example, biologists, geologists, chemists, physics, materials scientists, and archeologists, all sharing a common spectroscopic technique, also learned to appreciate the beauty and intricacies of each other's fields. As a laboratory-based technique, Moessbauer spectroscopy matured by the end of the 1970s. Further exciting developments took place when accelerator-based techniques were employed, like synchrotron radiation or 'in-beam'Moessbauer experiments with implanted radioactive ions. More recently, two Moessbauer spectrometers on the surface of the Mars kept the technique vibrant and viable up until present time. In this chapter, the authors look into some of the unique aspects of nuclear resonance excited with synchrotron radiation as a probe of condensed matter, including magnetism, valence, vibrations, and lattice dynamics, and review the development of nuclear resonance inelastic x-ray scattering (NRIXS) and synchrotron Moessbauer spectroscopy (SMS). However, to place these two techniques into some perspective with respect to other methods that yield related information, they display their version of a frequently used map of momentum and energy transfer diagram in figure 17.1. Here, various probes like electrons, neutrons, or light, i.e., Brillouin or Raman, and relatively newer forms of X-ray scattering are placed according to their range of energy and momentum transfer taking place during the measurements. Accordingly, NRIXS is a method that needs to be considered as a complementary probe to inelastic neutron and X-ray scattering, while SMS occupies a unique space due to its sensitivity to magnetism, structural deformations, valence, and spin states.

Alp, E. Ercan; Sturhahn, Wolfgang; Toellner, Thomas S.; Zhao, Jiyong; Leu, Bogdan M.

2012-05-09T23:59:59.000Z

139

Transmission Nuclear Resonance Fluorescence Measurements of 238U in Thick Targets  

E-Print Network (OSTI)

G. Rusev, and A.P. Tonchev, Transmission-based detection ofas it traverses the transmission detection sheet. The secondTransmission Nuclear Resonance Fluorescence Measurements of

Quiter, Brian J.

2011-01-01T23:59:59.000Z

140

'NMR on a Chip' Features NIST Magnetic Mini-Sensor  

Science Conference Proceedings (OSTI)

... of Standards and Technology (NIST) can detect nuclear magnetic resonance ... NIST Mini-Sensor May Have Biomedical and Security Applications). ...

2011-07-19T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

LANL sets magnetic record | National Nuclear Security Administration  

NLE Websites -- All DOE Office Websites (Extended Search)

sets magnetic record | National Nuclear Security Administration sets magnetic record | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > NNSA Blog > LANL sets magnetic record LANL sets magnetic record Posted By Office of Public Affairs Researchers at Los Alamos National Laboratory's biggest magnet facility recently produced magnetic fields in excess of 100 tesla while conducting

142

LANL sets magnetic record | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

sets magnetic record | National Nuclear Security Administration sets magnetic record | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > NNSA Blog > LANL sets magnetic record LANL sets magnetic record Posted By Office of Public Affairs Researchers at Los Alamos National Laboratory's biggest magnet facility recently produced magnetic fields in excess of 100 tesla while conducting

143

Solid-State Dynamic Nuclear Polarization at 263 GHz: Spectrometer Design and Experimental Results  

E-Print Network (OSTI)

Dynamic Nuclear Polarization (DNP) experiments transfer polarization from electron spins to nuclear spins with microwave irradiation of the electron spins for enhanced sensitivity in nuclear magnetic resonance (NMR) ...

Rosay, Melanie

144

Magnetic resonance as a channel of directed transmission of electromagnetic energy in animate nature  

E-Print Network (OSTI)

The phenomenon of magnetic resonance (either NMR or ESR) is a responce of atomic (molecular) system to the external electromagnetic effect. Electrons and nuclei, which possess magnetic moment, are the "magnetic antennas" in the biosystem "human being". They are able to receive (radiate) electromagnetic energy selectively in coordinates $H$ (magnetic field), $\

E. Ya. Fursa

2002-12-09T23:59:59.000Z

145

Resonance-like nuclear processes in solids: 3rd and 4th order processes  

E-Print Network (OSTI)

It is recognized that in the family of heavy charged particle and electron assisted double nuclear processes resonance-like behavior can appear. The transition rates of the heavy particle assisted 3rd-order and electron assisted 4th-order resonance like double nuclear processes are determined. The power of low energy nuclear reactions in $Ni-H$ systems formed in $Ni$ placed in $H_{2}$ gas environment is treated. Nuclear power produced by quasi-resonant electron assisted double nuclear processes in these $Ni-H$ systems is calculated. The power obtained tallies with experiments and its magnitude is considerable for practical applications.

Pter Klmn; Tams Keszthelyi

2013-03-06T23:59:59.000Z

146

Resonance-like nuclear processes in solids: 3rd and 4th order processes  

E-Print Network (OSTI)

It is recognized that in the family of heavy charged particle and electron assisted double nuclear processes resonance-like behavior can appear. The transition rates of the heavy particle assisted 3rd-order and electron assisted 4th-order resonance like double nuclear processes are determined. The power of low energy nuclear reactions in $Ni-H$ systems formed in $Ni$ placed in $H_{2}$ gas environment is treated. Nuclear power produced by quasi-resonant electron assisted double nuclear processes in these $Ni-H$ systems is calculated. The power obtained tallies with experiments and its magnitude is considerable for practical applications.

Klmn, Pter

2013-01-01T23:59:59.000Z

147

Nuclear quadrupole resonances in compact vapor cells: the crossover from the NMR to the NQR interaction regimes  

E-Print Network (OSTI)

We present the first experimental study that maps the transformation of nuclear quadrupole resonances from the pure nuclear quadrupole regime to the quadrupole-perturbed Zeeman regime. The transformation presents an interesting quantum-mechanical problem, since the quantization axis changes from being aligned along the axis of the electric-field gradient tensor to being aligned along the magnetic field. We achieve large nuclear quadrupole shifts for I = 3/2 131-Xe by using a 1 mm^3 cubic cell with walls of different materials. When the magnetic and quadrupolar interactions are of comparable size, perturbation theory is not suitable for calculating the transition energies. Rather than use perturbation theory, we compare our data to theoretical calculations using a Liouvillian approach and find excellent agreement.

E. A. Donley; J. L. Long; T. C. Liebisch; E. R. Hodby; T. A. Fisher; J. Kitching

2008-10-21T23:59:59.000Z

148

Spectroscopic imaging through magnetic resonance for brain tumour diagnostics: Recent achievements, dilemmas and potential solutions via advances in signal processing  

Science Conference Proceedings (OSTI)

In the very recent period Magnetic Resonance Spectroscopy (MRS) and Spectroscopic Imaging (MRSI) have become key diagnostic modalities for neuro-oncology. MRS and MRSI are now applied extensively for initial detection of brain tumours, for histopathologic ... Keywords: biomedical imaging, brain tumours, magnetic resonance spectroscopic imaging, magnetic resonance spectroscopy, metastatic disease

Karen Belki?; Devad Belki?

2004-04-01T23:59:59.000Z

149

Nuclear Resonance Fluorescence at MIT | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Resonance Fluorescence at MIT Resonance Fluorescence at MIT Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Nuclear Resonance Fluorescence at MIT Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Material Identification and Object Imaging Using Nuclear Resonance Fluorescence Developed at: Massachusetts Institute of Technology

150

THz Dynamic Nuclear Polarization NMR  

E-Print Network (OSTI)

Dynamic nuclear polarization (DNP) increases the sensitivity of nuclear magnetic resonance (NMR) spectroscopy by using high frequency microwaves to transfer the polarization of the electrons to the nuclear spins. The ...

Nanni, Emilio Alessandro

151

Magnetic resonance imaging of solvent transport in polymer networks  

SciTech Connect

The spectroscopic technique of magnetic resonance imaging (MRI) has recently provided a new window into transport of solvents in polymer networks. Diffusion of solvent as a rate-controlling phenomenon is paramount to understanding transport in many important industrial and biological processes, such as upgrading fossil fuels, film casting and coating, development of photoresists, design of drug-delivery systems, development of solvent resistant polymers, etc. By MRI mapping the migration of solvent molecules through various polymer specimens, researchers Robert Botto and George Cody of Argonne National Laboratory, with support from the Division of Chemical Sciences at DOE, were able to characterize and distinguish between different modes of transport behavior associated with fundamentally different types of polymer systems. The method was applied to rubbers, glassy polymers, and coals. In polymers shown to undergo a glass transition from a rigid to rubbery state, a sharply defined solvent front was observed that propagated through specimens in the manner of a constant velocity shock wave. This behavior was contrasted with a smooth solvent concentration gradient found in polymer systems where no glass transition was observed. The results of this analysis have formed the basis of a new model of anomalous transport in polymeric solids and are helping to ascertain fundamental information on the molecular architectures of these materials.

Botto, R.E.; Cody, G.D.

1995-02-01T23:59:59.000Z

152

Optical and magneto-optical properties of one-dimensional magnetized coupled resonator plasma photonic crystals  

Science Conference Proceedings (OSTI)

In this paper, the optical and magneto-optical properties of one-dimensional magnetized coupled resonator plasma photonic crystals have been investigated. We use transfer matrix method to solve our magnetized coupled resonator plasma photonic crystals consist of dielectric and magnetized plasma layers. The results of the change in the optical and magneto-optical properties of structure as a result of the alteration in the structural properties such as thickness, plasma frequency and collision frequency, plasma filling factor, number of resonators and dielectric constant of dielectric layers and external magnetic field have been reported. The main feature of this structure is a good magneto-optical rotation that takes place at the defect modes and the edge of photonic band gap of our proposed optical magnetized plasma waveguide. Our outcomes demonstrate the potential applications of the device for tunable and adjustable filters or reflectors and active magneto-optic in microwave devices under structural parameter and external magnetic field.

Hamidi, S. M. [Laser and Plasma Research Institute, G. C., Shahid Beheshti University, Tehran 1983963113 (Iran, Islamic Republic of)

2012-01-15T23:59:59.000Z

153

Nuclear Resonance Fluorescence for Material Verification in Dismantlement  

Science Conference Proceedings (OSTI)

Nuclear resonance fluorescence (NRF) is a well-established physical process that provides an isotope-specific signature that can be exploited for isotopic detection and characterization of samples. Pacific Northwest National Laboratory has been investigating possible applications of NRF for national security. Of the investigated applications, the verification of material in the dismantlement process is the most promising. Through a combination of benchmarking measurements and radiation transport modeling, we have shown that NRF techniques with existing bremsstrahlung photon sources and a modest detection system can be used to detect highly enriched uranium in the quantities and time limits relevant to the dismantlement process. Issues such as orientation, placement and material geometry do not significantly impact the sensitivity of the technique. We have also investigated how shielding of the uranium would be observed through non-NRF processes to enable the accurate assay of the material. This paper will discuss our findings on how NRF and photon-interrogation techniques may be applied to the material verification in the dismantlement process.

Warren, Glen A.; Detwiler, Rebecca S.

2011-10-01T23:59:59.000Z

154

HST.583 Functional Magnetic Resonance Imaging: Data Acquisition and Analysis, Fall 2006  

E-Print Network (OSTI)

This team taught, multidisciplinary course covers the fundamentals of magnetic resonance imaging relevant to the conduct and interpretation of human brain mapping studies. The challenges inherent in advancing our knowledge ...

Gollub, Randy L.

155

Multimodal neuroimaging with simultaneous electroencephalogram and high-field functional magnetic resonance imaging  

E-Print Network (OSTI)

Simultaneous recording of electroencephalogram (EEG) and functional magnetic resonance imaging (tMRI) is an important emerging tool in functional neuroimaging with the potential to reveal new mechanisms for brain function ...

Purdon, Patrick L. (Patrick Lee), 1974-

2005-01-01T23:59:59.000Z

156

Microfluidically Cryo-Cooled Planar Coils for Magnetic Resonance Imaging  

E-Print Network (OSTI)

High signal-to-noise ratio (SNR) is typically required for higher resolution and faster speed in magnetic resonance imaging (MRI). Planar microcoils as receiver probes in MRI systems offer the potential to be configured into array elements for fast imaging as well as to enable the imaging of extremely small objects. Microcoils, however, are thermal noise dominant and suffer limited SNR. Cryo-cooling for the microcoils can reduce the thermal noise, however conventional cryostats are not optimum for the microcoils because they typically use a thick vacuum gap to keep samples to be imaged to near room temperature during cryo-cooling. This vacuum gap is typically larger than the most sensitive region of the microcoils that defines the imaging depth, which is approximately the same as the diameters of the microcoils. Here microfluidic technology is utilized to locally cryo-cool the microcoils and minimize the thermal isolation gap so that the imaging surface is within the imaging depth of the microcoils. The first system consists of a planar microcoil with microfluidically cryo-cooling channels, a thin N2 gap and an imaging. The microcoil was locally cryo-cooled while maintaining the sample above 8C. MR images using a 4.7 Tesla MRI system shows an average SNR enhancement of 1.47 fold. Second, the system has been further developed into a cryo-cooled microcoil system with inductive coupling to cryo-cool both the microcoil and the on-chip microfabricated resonating capacitor to further improve the Q improvement. Here inductive coupling was used to eliminate the physical connection between the microcoil and the tuning network so that a single cryocooling microfluidic channel could enclose both the microcoil and the capacitor with minimum loss in cooling capacity. Q improvement was 2.6 fold compared to a conventional microcoil with high-Q varactors and transmission line connection. Microfluidically tunable capacitors with the 653% tunability and Q of 1.3 fold higher compared to a conventional varactor have been developed and demonstrated as matching/tuning networks as a proof of concept. These developed microfluidically cryo-cooling system and tunable capacitors for improving SNR will potentially allow MR microcoils to have high-resolution images over small samples.

Koo, Chiwan

2013-08-01T23:59:59.000Z

157

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials  

DOE Patents (OSTI)

Method comprising obtaining an NMR measurement from a sample wherein an ultra-low field NMR system probes the sample and produces the NMR measurement and wherein a sampling temperature, prepolarizing field, and measurement field are known; detecting the NMR measurement by means of inductive coils; analyzing the NMR measurement to obtain at least one measurement feature wherein the measurement feature comprises T1, T2, T1.rho., or the frequency dependence thereof; and, searching for the at least one measurement feature within a database comprising NMR reference data for at least one material to determine if the sample comprises a material of interest.

Matlashov, Andrei Nikolaevich; Urbaitis, Algis V.; Savukov, Igor Mykhaylovich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry

2013-03-05T23:59:59.000Z

158

Using Nuclear Resonance Fluorescence for Nondestructive Isotopic Analysis  

E-Print Network (OSTI)

screening and nuclear nonproliferation applications[2,3].of the Office of Nonproliferation and International

Ludewigt, Bernhard A.

2010-01-01T23:59:59.000Z

159

X-ray resonant magnetic scattering study of magnetic stripe domains in a-GdFe thin films  

SciTech Connect

X-ray resonant magnetic scattering (XRMS) has been used to investigate the structure of magnetic stripe domain patterns in thin amorphous GdFe films. Under the influence of a perpendicular magnetic field, the scattered intensity displays a smooth transition from a structure factor of correlated stripes to the form factor of isolated domains. We derive a quite general expression that relates the total scattered intensity of XRMS to the absolute value of the magnetization. Furthermore, we compare our results for the domain period with domain theory. We obtain good agreement for prealigned stripes, but disorder tends to lead to an overestimation of the period measured with XRMS.

Miguel, J.; Peters, J. F.; Toulemonde, O. M.; Goedkoop, J. B. [Van der Waals-Zeeman Institute, University of Amsterdam, Valckenierstraat 65, 1018 XE, Amsterdam (Netherlands); Dhesi, S. S.; Brookes, N. B. [European Synchrotron Radiation Facility, ESRF, Boite Postale 220, F-38043 Grenoble Cedex (France)

2006-09-01T23:59:59.000Z

160

Electrically detected magnetic resonance in a W-band microwave cavity  

SciTech Connect

We describe a low-temperature sample probe for the electrical detection of magnetic resonance in a resonant W-band (94 GHz) microwave cavity. The advantages of this approach are demonstrated by experiments on silicon field-effect transistors. A comparison with conventional low-frequency measurements at X-band (9.7 GHz) on the same devices reveals an up to 100-fold enhancement of the signal intensity. In addition, resonance lines that are unresolved at X-band are clearly separated in the W-band measurements. Electrically detected magnetic resonance at high magnetic fields and high microwave frequencies is therefore a very sensitive technique for studying electron spins with an enhanced spectral resolution and sensitivity.

Lang, V.; Lo, C. C.; George, R. E.; Lyon, S. A.; Bokor, J.; Schenkel, T.; Ardavan, A.; Morton, J. J. L.

2011-01-14T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Application of Parallel Imaging to Murine Magnetic Resonance Imaging  

E-Print Network (OSTI)

The use of parallel imaging techniques for image acceleration is now common in clinical magnetic resonance imaging (MRI). There has been limited work, however, in translating the parallel imaging techniques to routine animal imaging. This dissertation describes foundational level work to enable parallel imaging of mice on a 4.7 Tesla/40 cm bore research scanner. Reducing the size of the hardware setup associated with typical parallel imaging was an integral part of achieving the work, as animal scanners are typically small-bore systems. To that end, an array element design is described that inherently decouples from a homogenous transmit field, potentially allowing for elimination of typically necessary active detuning switches. The unbalanced feed of this "dual-plane pair" element also eliminates the need for baluns in this case. The use of the element design in a 10-channel adjustable array coil for mouse imaging is presented, styled as a human cardiac top-bottom half-rack design. The design and construction of the homogenous transmit birdcage coil used is also described, one of the necessary components to eliminating the active detuning networks on the array elements. In addition, the design of a compact, modular multi-channel isolation preamplifier board is described, removing the preamplifiers from the elements and saving space in the bore. Several additions/improvements to existing laboratory infrastructure needed for parallel imaging of live mice are also described, including readying an animal preparation area and developing the ability to maintain isoflurane anesthesia delivery during scanning. In addition, the ability to trigger the MRI scanner to the ECG and respiratory signals from the mouse in order to achieve images free from physiological motion artifacts is described. The imaging results from the compact 10-channel mouse array coils are presented, and the challenges associated with the work are described, including difficulty achieving sample-loss dominance and signal-to-noise ratio (SNR) limitations. In conclusion, in vivo imaging of mice with cardiac and respiratory gating has been demonstrated. Compact array coils tailored for mice have been studied and potential future work and design improvements for our lab in this area are discussed.

Chang, Chieh-Wei 1980-

2012-12-01T23:59:59.000Z

162

Nuclear quadrupole resonance of an electronically excited state from high-resolution hole-burning spectroscopy  

E-Print Network (OSTI)

Nuclear quadrupole resonance of an electronically excited state from high-resolution hole-burning 2003; published 5 May 2003 Hole-burning spectroscopy can eliminate inhomogeneous broadening and thereby, the homogeneous linewidth is often small compared to the splittings due to nuclear-spin interactions. Hole-burning

Suter, Dieter

163

Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel  

Science Conference Proceedings (OSTI)

The Next Generation Safeguard Initiative (NGSI) of the U.S Department of Energy is supporting a multi-lab/university collaboration to quantify the plutonium (Pu) mass in spent nuclear fuel (SNF) assemblies and to detect the diversion of pins with non-destructive assay (NDA) methods. The following 14 NDA techniques are being studied: Delayed Neutrons, Differential Die-Away, Differential Die-Away Self-Interrogation, Lead Slowing Down Spectrometer, Neutron Multiplicity, Passive Neutron Albedo Reactivity, Total Neutron (Gross Neutron), X-Ray Fluorescence, {sup 252}Cf Interrogation with Prompt Neutron Detection, Delayed Gamma, Nuclear Resonance Fluorescence, Passive Prompt Gamma, Self-integration Neutron Resonance Densitometry, and Neutron Resonance Transmission Analysis. Understanding and maturity of the techniques vary greatly, ranging from decades old, well-understood methods to new approaches. Nuclear Resonance Fluorescence (NRF) is a technique that had not previously been studied for SNF assay or similar applications. Since NRF generates isotope-specific signals, the promise and appeal of the technique lies in its potential to directly measure the amount of a specific isotope in an SNF assay target. The objectives of this study were to design and model suitable NRF measurement methods, to quantify capabilities and corresponding instrumentation requirements, and to evaluate prospects and the potential of NRF for SNF assay. The main challenge of the technique is to achieve the sensitivity and precision, i.e., to accumulate sufficient counting statistics, required for quantifying the mass of Pu isotopes in SNF assemblies. Systematic errors, considered a lesser problem for a direct measurement and only briefly discussed in this report, need to be evaluated for specific instrument designs in the future. Also, since the technical capability of using NRF to measure Pu in SNF has not been established, this report does not directly address issues such as cost, size, development time, nor concerns related to the use of Pu in measurement systems. This report discusses basic NRF measurement concepts, i.e., backscatter and transmission methods, and photon source and {gamma}-ray detector options in Section 2. An analytical model for calculating NRF signal strengths is presented in Section 3 together with enhancements to the MCNPX code and descriptions of modeling techniques that were drawn upon in the following sections. Making extensive use of the model and MCNPX simulations, the capabilities of the backscatter and transmission methods based on bremsstrahlung or quasi-monoenergetic photon sources were analyzed as described in Sections 4 and 5. A recent transmission experiment is reported on in Appendix A. While this experiment was not directly part of this project, its results provide an important reference point for our analytical estimates and MCNPX simulations. Used fuel radioactivity calculations, the enhancements to the MCNPX code, and details of the MCNPX simulations are documented in the other appendices.

Ludewigt, Bernhard A; Quiter, Brian J.; Ambers, Scott D.

2011-01-14T23:59:59.000Z

164

Resonance enhancement of nonsequential double ionization by a magnetic field  

Science Conference Proceedings (OSTI)

We investigate nonsequential double ionization (NSDI) of helium by using an additional magnetic field parallel to the polarization of the laser pulse. By exploring the ability of a magnetic field for focusing the selected trajectories that contribute to the NSDI, we have found that the yield of NSDI, as a function of the magnetic-field strength, shows different behavior for different laser intensities. As a result, an additional magnetic field provides a way to identify that the NSDI mechanism of laser-assisted collision ionization begins to play an important role as the laser intensity increases.

Li Hongyun [Department of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, Peking University, Beijing 100871 (China); Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Chen Jing; Liu Jie [Center for Nonlinear Studies, Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Jiang Hongbing; Gong Qihuang [Department of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, Peking University, Beijing 100871 (China); Fu Panming; Wang Bingbing [Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Yan Zongchao [Department of Physics, University of New Brunswick, Fredericton, New Brunswick, E3B 5A3 (Canada)

2011-01-15T23:59:59.000Z

165

A unified view of coherent and incoherent dihydrogen exchange in transition metal hydrides by nuclear resonance and inelastic neutron scattering  

SciTech Connect

In this paper a unified view of coherent and incoherent dihydrogen exchange in transition metal hydrides by nuclear magnetic resonance (NMR) and inelastic neutron scattering (INS) is presented. It is shown that both exchange processes coexist i.e. do not transform into each other although they may dominate the spectra in different temperature ranges. This superposition is the consequence of the incorporation of the tunnel frequency J of the coherent process into the nuclear two-spin hamiltonian of hydrogen pairs which allows to treat the problem using the well known density matrix theory of NMR line-shapes developed by Alexander and Binsch. It is shown that this theory can also be used to predict the line-shapes of the rotational tunneling transitions observed in the INS spectra of transition metal dihydrogen complexes and that both NMR and INS spectra depend on similar parameters.

Limbach, H.H.; Ulrich, S.; Buntkowsky, G. [Freie Univ. Berlin (Germany). Inst. fuer Organische Chemie; Sabo-Etienne, S.; Chaudret, B. [Toulouse-3 Univ., 31 (France). Lab. de Chimie de Coordination du C.N.R.S.; Kubas, G.J.; Eckert, J. [Los Alamos National Lab., NM (United States)

1995-08-12T23:59:59.000Z

166

Footprint structures due to resonant magnetic perturbations in DIII-D  

SciTech Connect

Numerical modeling of the typical footprint structures on the target plates of a divertor tokamak is presented. In the tokamak DIII-D [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] toroidal mode number n=3 resonant magnetic perturbations are responsible for characteristic footprint stripes. The numerics can resolve substructures within each footprint stripe, which are related to the internal magnetic topology. It is shown that the footprint structures on the inner target plate can be predicted by the unstable manifolds of the separatrix and the q=4 resonant surface. By their intersection with the divertor target plate the unstable manifolds form the footprint boundary and substructures within. Based on the manifold analysis, the boundaries and interior structures of the footprints are explained. A direct connection of all magnetic resonances inside the stochastic plasma volume to the target plates is verified.

Wingen, A.; Spatschek, K. H. [Institut fuer Theoretische Physik, Heinrich-Heine-Universitaet Duesseldorf, D-40225 Duesseldorf (Germany); Evans, T. E. [General Atomics, San Diego, California 92186-5608 (United States)

2009-04-15T23:59:59.000Z

167

Observation of Magnetic Resonances in Electron Clouds in a Positron Storage Ring  

SciTech Connect

The first experimental observation of magnetic resonances in electron clouds is reported. The resonance was observed as a modulation in cloud intensity for uncoated as well as TiN-coated aluminum surfaces in the positron storage ring of the PEP-II collider at SLAC. Electron clouds frequently arise in accelerators of positively charged particles, and severely impact the machines performance. The TiN coating was found to be an effective remedy, reducing the cloud intensity by three orders of magnitude.

Pivi, M.T.F.; Ng, J.S.T.; Cooper, F.; Kharakh, D.; King, F.; Kirby, R.E.; Kuekan, B.; Spencer, Cherrill M.; Raubenheimer, T.O.; Wang, L.F.; /SLAC

2011-08-24T23:59:59.000Z

168

Temperature-controlled molecular depolarization gates in nuclear magnetic resonance  

SciTech Connect

Down the drain: Cryptophane cages in combination with selective radiofrequency spin labeling can be used as molecular 'transpletor' units for transferring depletion of spin polarization from a hyperpolarized 'source' spin ensemble to a 'drain' ensemble. The flow of nuclei through the gate is adjustable by the ambient temperature, thereby enabling controlled consumption of hyperpolarization.

Schroder, Leif; Schroder, Leif; Chavez, Lana; Meldrum, Tyler; Smith, Monica; Lowery, Thomas J.; E. Wemmer, David; Pines, Alexander

2008-02-27T23:59:59.000Z

169

High-pressure Magic Angle Spinning Nuclear Magnetic Resonance  

Science Conference Proceedings (OSTI)

A high-pressure magic angle spinning (MAS) NMR capability, consisting of a reusable high-pressure MAS rotor, a high-pressure loading/reaction chamber for in situ sealing and re-opening of the high-pressure MAS rotor, and a MAS probe with a localized RF coil for background signal suppression, is reported. The unusual technical challenges associated with development of a reusable high-pressure MAS rotor are addressed in part by modifying standard ceramics for the rotor sleeve to include micro-groves at the internal surface at both ends of the cylinder. In this way, not only is the advantage of ceramic cylinders for withstanding very high-pressure utilized, but also plastic bushings can be glued tightly in place so that other plastic sealing mechanisms/components and O-rings can be mounted to create the desired high-pressure seal. Using this strategy, sealed internal pressures exceeding 150 bars have been achieved and sustained under ambient external pressure with minimal penetration loss of pressure for 72 hours. As an application example, in situ 13C MAS NMR studies of mineral carbonation reaction intermediates and final products of forsterite (Mg2SiO4) reacted with supercritical CO2 and H2O at 150 bar and 50?C are reported, with relevance to geological sequestration of carbon dioxide.

Hoyt, David W.; Turcu, Romulus VF; Sears, Jesse A.; Rosso, Kevin M.; Burton, Sarah D.; Felmy, Andrew R.; Hu, Jian Z.

2011-10-01T23:59:59.000Z

170

Advances in Zero-Field Nuclear Magnetic Resonance Spectroscopy  

E-Print Network (OSTI)

is then loaded onto the TTL pulse generator, PulseBlasterJP303. The PulseBlaster sends TTL pulses to a home builtPulseBlaster which puts out TTL signals that are amplified

Theis, Thomas

2012-01-01T23:59:59.000Z

171

Nuclear Magnetic Resonance Studies of Resorcinol-Formaldehyde Aerogels  

Science Conference Proceedings (OSTI)

In this article we report a detailed study of resorcinol-formaldehyde (RF) aerogels prepared under different processing conditions, [resorcinol]/[catalyst] (R/C) ratios in the starting sol-gel solutions, using continuous flow hyperpolarized 129Xe NMR in combination with solid-state 13C and two-dimensional wide-line separation (2D-WISE) NMR techniques. The degree of polymerization and the mobility of the cross-linking functional groups in RF aerogels are examined and correlated with the R/C ratios. The origin of different adsorption regions is evaluated using both co-adsorption of chloroform and 2D EXSY 129Xe NMR. A hierarchical set of Xe exchange processes in RF aerogels is found using 2D EXSY 129Xe NMR. The exchange of Xe gas follows the sequence (from fastest to slowest): mesopores with free gas, gas in meso- and micro-pores, free gas with micropores, and, finally, among micropore sites. The volume-to-surface-area (Vg/S) ratios for aerogels are measured for the first time without the use of geometric models. The Vg/S parameter, which is related both to the geometry and the interconnectivity of the pore space, has been found to correlate strongly with the R/C ratio and exhibits an unusually large span: an increase in the R/C ratio from 50 to 500 results in about a 5-fold rise in Vg/S.

Moudrakovski, Igor L.; Ratcliffe, C I.; Ripmeester, J A.; Wang, Li Q.; Exarhos, Gregory J.; Baumann, T; Satcher, J H.

2005-06-09T23:59:59.000Z

172

On Magic State Distillation using Nuclear Magnetic Resonance.  

E-Print Network (OSTI)

??Physical implementations of quantum computers will inevitably be subject to errors. However, provided that the error rate is below some threshold, it is theoretically possible (more)

Hubbard, Adam A.

2008-01-01T23:59:59.000Z

173

Solving Quantum Ground-State Problems with Nuclear Magnetic Resonance  

E-Print Network (OSTI)

Quantum ground-state problems are computationally hard problems; for general many-body Hamiltonians, there is no classical or quantum algorithm known to be able to solve them efficiently. Nevertheless, if a trial wavefunction approximating the ground state is available, as often happens for many problems in physics and chemistry, a quantum computer could employ this trial wavefunction to project the ground state by means of the phase estimation algorithm (PEA). We performed an experimental realization of this idea by implementing a variational-wavefunction approach to solve the ground-state problem of the Heisenberg spin model with an NMR quantum simulator. Our iterative phase estimation procedure yields a high accuracy for the eigenenergies (to the 10^-5 decimal digit). The ground-state fidelity was distilled to be more than 80%, and the singlet-to-triplet switching near the critical field is reliably captured. This result shows that quantum simulators can better leverage classical trial wavefunctions than c...

Li, Zhaokai; Chen, Hongwei; Lu, Dawei; Whitfield, James D; Peng, Xinhua; Aspuru-Guzik, Aln; Du, Jiangfeng

2011-01-01T23:59:59.000Z

174

Solving Quantum Ground-State Problems with Nuclear Magnetic Resonance  

E-Print Network (OSTI)

Quantum ground-state problems are computationally hard problems; for general many-body Hamiltonians, there is no classical or quantum algorithm known to be able to solve them efficiently. Nevertheless, if a trial wavefunction approximating the ground state is available, as often happens for many problems in physics and chemistry, a quantum computer could employ this trial wavefunction to project the ground state by means of the phase estimation algorithm (PEA). We performed an experimental realization of this idea by implementing a variational-wavefunction approach to solve the ground-state problem of the Heisenberg spin model with an NMR quantum simulator. Our iterative phase estimation procedure yields a high accuracy for the eigenenergies (to the 10^-5 decimal digit). The ground-state fidelity was distilled to be more than 80%, and the singlet-to-triplet switching near the critical field is reliably captured. This result shows that quantum simulators can better leverage classical trial wavefunctions than classical computers.

Zhaokai Li; Man-Hong Yung; Hongwei Chen; Dawei Lu; James D. Whitfield; Xinhua Peng; Aln Aspuru-Guzik; Jiangfeng Du

2011-06-02T23:59:59.000Z

175

Single-spin measurements for quantum computation using magnetic resonance force microscopy  

SciTech Connect

The quantum theory of a singlespin measurements using a magnetic resonance force microscopy is presented. We use an oscillating cantilever-driven adiabatic reversals technique. The frequency shift of the cantilever vibrations is estimated. We show that the frequency shift causes the formation of the Schroedinger cat state for the cantilever. The interaction between the cantilever and the environment quickly destroys the coherence between the two cantilever trajectories. It is shown that using partial adiabatic reversals one can obtain a significant increase in the frequency shift. We discuss the possibility of sub-magneton spin density detection in molecules using magnetic resonance force microscopy.

Berman, G. P. (Gennady P.); Borgonovi, F.; Rinkevicius, Z.; Tsifrinovich, V. I. (Vladimir I.)

2004-01-01T23:59:59.000Z

176

Examining 239Pu and 240Pu Nuclear Resonance Fluorescence Measurements on Spent Fuel for Nuclear Safeguards  

E-Print Network (OSTI)

Fluorescence for Spent Nuclear Fuel Assay, Inst. of Nucl.239 Pu content in spent nuclear fuel [4, 5]. Development ofin the context of spent nuclear fuel, summarizes the results

Quiter, Brian

2013-01-01T23:59:59.000Z

177

Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel  

E-Print Network (OSTI)

09-01188, ANS Advances in Nuclear Fuel Management IV, HiltonParameter Library Spent Nuclear Fuel Transmission detector (Pu) mass in spent nuclear fuel (SNF) assemblies and to

Ludewigt, Bernhard A

2011-01-01T23:59:59.000Z

178

Agentification of Markov model-based segmentation: Application to magnetic resonance brain scans  

Science Conference Proceedings (OSTI)

Objective: Markov random field (MRF) models have been traditionally applied to the task of robust-to-noise image segmentation. Most approaches estimate MRF parameters on the whole image via a global expectation-maximization (EM) procedure. The resulting ... Keywords: Distributed expectation maximization, Magnetic resonance brain scan segmentation, Markov random field, Medical imaging, Multiagents system

Benoit Scherrer; Michel Dojat; Florence Forbes; Catherine Garbay

2009-05-01T23:59:59.000Z

179

Detecting tumor responses to treatment using hyperpolarized 13C magnetic resonance spectroscopic imaging  

E-Print Network (OSTI)

- labeled bicarbonate. Nature 2008, 453:940-943. doi:10.1038/nrc2289 Cite this article as: Brindle: Detecting tumor responses to treatment using hyperpolarized 13C magnetic resonance spectroscopic imaging. BMC Proceedings 2010 4(Suppl 2):O24. Correspondence...

2010-09-24T23:59:59.000Z

180

Fiber-Optic Stethoscope: A Cardiac Monitoring and Gating System for Magnetic Resonance Microscopy  

E-Print Network (OSTI)

Fiber-Optic Stethoscope: A Cardiac Monitoring and Gating System for Magnetic Resonance Microscopy monitoring and gating purposes. The fiber-optic stethoscope system offers a novel approach to measuring) small enough for use on rats and mice. METHODS Fiber-Optic Stethoscope System Design As shown in the MR

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Automatic segmentation of non-enhancing brain tumors in magnetic resonance images  

Science Conference Proceedings (OSTI)

Tumor segmentation from magnetic resonance (MR) images may aid in tumor treatment by tracking the progress of tumor growth and/or shrinkage. In this paper we present the first automatic segmentation method which separates non-enhancing brain tumors from ... Keywords: Automatic tissue classification, Fuzzy clustering, Image processing, MRI, Non-enhancing brain tumors

Lynn M Fletcher-Heath; Lawrence O Hall; Dmitry B Goldgof; F.Reed Murtagh

2001-01-01T23:59:59.000Z

182

Segmentation of female pelvic organs in axial magnetic resonance images using coupled geometric deformable models  

Science Conference Proceedings (OSTI)

The segmentation of pelvic structures in magnetic resonance (MR) images of the female pelvic cavity is a challenging task. This paper proposes the use of three novel geometric deformable models to segment the bladder, vagina and rectum in axial MR images. ... Keywords: Bladder, Image segmentation, Imaging appearance, Level set, Prior shape knowledge, Rectum, Vagina

Zhen Ma; Renato M. Natal Jorge; Teresa Mascarenhas; JoO Manuel R. S. Tavares

2013-05-01T23:59:59.000Z

183

Investigation of ELM [edge localized mode] Dynamics with the Resonant Magnetic Perturbation Effects  

SciTech Connect

Topics covered are: anomalous transport and E ? B flow shear effects in the H-mode pedestal; RMP (resonant magnetic perturbation) effects in NSTX discharges; development of a scaling of H-mode pedestal in tokamak plasmas with type I ELMs (edge localized modes); and divertor heat load studies.

Alexei Y. Pankin; Arnold H. Kritz

2011-07-19T23:59:59.000Z

184

Effect of Electric and Magnetic Fields on Spin Dynamics in the Resonant Electric Dipole Moment Experiment  

E-Print Network (OSTI)

A buildup of the vertical polarization in the resonant electric dipole moment (EDM) experiment [Y. F. Orlov, W. M. Morse, and Y. K. Semertzidis, Phys. Rev. Lett. 96, 214802 (2006)] is affected by a horizontal electric field in the particle rest frame oscillating at a resonant frequency. This field is defined by the Lorentz transformation of an oscillating longitudinal electric field and a uniform vertical magnetic one. The effect of a longitudinal electric field is significant, while the contribution from a magnetic field caused by forced coherent longitudinal oscillations of particles is dominant. The effect of electric field on the spin dynamics was not taken into account in previous calculations. This effect is considerable and leads to decreasing the EDM effect for the deuteron and increasing it for the proton. The formula for resonance strengths in the EDM experiment has been derived. The spin dynamics has been calculated.

Alexander J. Silenko

2006-04-11T23:59:59.000Z

185

Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel  

E-Print Network (OSTI)

Level Scheme Library Depleted Uranium Evaluated Nuclear Datafuel and the 238 U in depleted uranium (DU) was used as a

Ludewigt, Bernhard A

2011-01-01T23:59:59.000Z

186

Nuclear resonant X-ray spectroscopy of (Mg,Fe)SiO3 orthoenstatites JENNIFER M. JACKSON1,*, EMILY A. HAMECHER1  

E-Print Network (OSTI)

Nuclear resonant X-ray spectroscopy of (Mg,Fe)SiO3 orthoenstatites JENNIFER M. JACKSON1,*, EMILY A, 9700 S. Cass Ave., Argonne, IL 60439, USA Abstract: We present nuclear resonant inelastic X-ray scattering (NRIXS) and synchrotron Mo¨ssbauer spectroscopy (SMS) measurements, both nuclear resonant X

Jackson, Jennifer M.

187

Direct imaging of neural currents using ultra-low field magnetic resonance techniques  

DOE Patents (OSTI)

Using resonant interactions to directly and tomographically image neural activity in the human brain using magnetic resonance imaging (MRI) techniques at ultra-low field (ULF), the present inventors have established an approach that is sensitive to magnetic field distributions local to the spin population in cortex at the Larmor frequency of the measurement field. Because the Larmor frequency can be readily manipulated (through varying B.sub.m), one can also envision using ULF-DNI to image the frequency distribution of the local fields in cortex. Such information, taken together with simultaneous acquisition of MEG and ULF-NMR signals, enables non-invasive exploration of the correlation between local fields induced by neural activity in cortex and more `distant` measures of brain activity such as MEG and EEG.

Volegov, Petr L. (Los Alamos, NM); Matlashov, Andrei N. (Los Alamos, NM); Mosher, John C. (Los Alamos, NM); Espy, Michelle A. (Los Alamos, NM); Kraus, Jr., Robert H. (Los Alamos, NM)

2009-08-11T23:59:59.000Z

188

Power Quality Investigation at a Midwest Hospital: Magnetic Resonance Imaging System  

Science Conference Proceedings (OSTI)

Recently, a Midwest hospital contacted its electric utility about malfunctions involving imaging systems including magnetic resonance imaging (MRI) and computed tomography (CT). The MRI system was the primary concern for the hospital. The MRI system was manufactured by a leading imaging system manufacturer and the CT system was manufactured by another leading imaging system manufacturer. To begin investigating the problem, the hospital requested that power-line monitoring be conducted at the facility. Th...

2007-07-26T23:59:59.000Z

189

Nuclear Resonance Fluorescence Excitations around 2 MeV in U-235 and Pu-239  

DOE Green Energy (OSTI)

A search for nuclear resonance fluorescence excitations in U and Pu within the energy range of 1.0- to 2.5-MeV was performed using a 4-MeV, continuous, bremsstrahlung source at the High Voltage Research Laboratory at the Massachusetts Institute of Technology. Measurements utilizing high purity Ge detectors at back angles identified 9 photopeaks in U-235 and 13 photopeaks in Pu-239 in this energy range, most likely dipole excitations. These resonances provide unique signatures that allow the materials to be non-intrusively detected in a variety of environments including fuel cells, waste drums, vehicles and containers. The presence and properties of these states may prove useful in understanding the nuclear structure of even - odd nuclei.

Bertozzi, William; Caggiano, Joseph A.; Hensley, Walter K.; Johnson, Micah S.; Korbly, Steve; Ledoux, Robert; McNabb, Dennis P.; norman, E. B.; Park, William H.; Warren, Glen A.

2008-10-01T23:59:59.000Z

190

Minute Effects of Sex on the Aging Brain: A Multisample Magnetic Resonance Imaging Study of Healthy Aging and Alzheimer's Disease  

E-Print Network (OSTI)

Age is associated with substantial macrostructural brain changes. While some recent magnetic resonance imaging studies have reported larger age effects in men than women, others find no sex differences. As brain morphometry ...

Fjell, Anders M.

191

Whole-heart magnetic resonance coronary angiography with multiple breath-holds and automatic breathing-level tracking  

Science Conference Proceedings (OSTI)

Whole-heart (WH) magnetic resonance coronary angiography (MRCA) studies are usually performed during free breathing while monitoring the position of the diaphragm with real-time motion correction. However

Shigehide Kuhara; Ayako Ninomiya; Tomohisa Okada; Shotaro Kanao; Toshikazu Kamae; Kaori Togashi

2010-01-01T23:59:59.000Z

192

Resonance Region Nuclear Data Analysis to Support Advanced Fuel Cycle Development  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) and the Korean Atomic Energy Research Institute (KAERI) are performing collaborative research as part of a three-year United States (U.S.) / Republic of Korea (ROK) International Nuclear Energy Research Initiative (I-NERI) project to provide improved neutron cross-section data with uncertainty or covariance data important for advanced fuel cycle and nuclear safeguards applications. ORNL and KAERI have initiated efforts to prepare new cross-section evaluations for 240Pu, 237Np, and the stable Cm isotopes. At the current stage of the I-NERI project, ORNL has recently completed a preliminary resonance-region cross-section evaluation with covariance data for 240Pu and initiated resonance evaluation efforts for 237Np and 244Cm. Likewise, KAERI is performing corresponding high-energy cross-section analyses (i.e., above the resonance region) for the noted isotopes. The paper provides results pertaining to the new resonance region evaluation efforts with emphasis on the new 240Pu evaluation.

Dunn, Michael E [ORNL; Derrien, Herve [ORNL; Leal, Luiz C [ORNL; Gil, Choong-Sup [Korea Atomic Energy Research Institute; Kim, D. [Korea Atomic Energy Research Institute

2011-01-01T23:59:59.000Z

193

Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel  

E-Print Network (OSTI)

and S.J. Thompson,Determining Plutonium in Spent Fuel withTobin, Determination of Plutonium Content in Spent FuelFluorescence to Measure Plutonium Mass in Spent Nuclear Fuel

Ludewigt, Bernhard A

2011-01-01T23:59:59.000Z

194

Liquid-State NMR and Scalar Couplings in Microtesla Magnetic Fields  

ference in free energy of solvation between the ... K. S. Richardson, Mechanism and Theory in Organic Chemistry ... We obtained nuclear magnetic resonance ...

195

Transmission Nuclear Resonance Fluorescence Measurements of 238U in Thick Targets  

SciTech Connect

Transmission nuclear resonance fluorescence measurements were made on targets consisting of Pb and depleted U with total areal densities near 86 g/cm2. The 238U content n the targets varied from 0 to 8.5percent (atom fraction). The experiment demonstrates the capability of using transmission measurements as a non-destructive technique to identify and quantify the presence of an isotope in samples with thicknesses comparable to he average thickness of a nuclear fuel assembly. The experimental data also appear to demonstrate the process of notch refilling with a predictable intensity. Comparison of measured spectra to previous backscatter 238U measurements indicates general agreement in observed excited states. Two new 238U excited states and possibly a third state have also been observed.

Quiter, Brian J.; Ludewigt, Bernhard A.; Mozin, Vladimir V.; Wilson, Cody; Korbly, Steve

2010-08-31T23:59:59.000Z

196

Stability of Relativistic Matter with Magnetic Fields for Nuclear Charges up to the Critical Value  

E-Print Network (OSTI)

We give a proof of stability of relativistic matter with magnetic fields all the way up to the critical value of the nuclear charge $Z\\alpha=2/\\pi$.

Rupert L. Frank; Elliott H. Lieb; Robert Seiringer

2006-10-24T23:59:59.000Z

197

Diffusion-Weighted Magnetic Resonance Imaging in Monitoring Rectal Cancer Response to Neoadjuvant Chemoradiotherapy  

SciTech Connect

Purpose: To prospectively monitor the response in patients with locally advanced nonmucinous rectal cancer after chemoradiotherapy (CRT) using diffusion-weighted magnetic resonance imaging. The histopathologic finding was the reference standard. Methods and Materials: The institutional review board approved the present study. A total of 62 patients (43 men and 19 women; mean age, 64 years; range, 28-83) provided informed consent. T{sub 2}- and diffusion-weighted magnetic resonance imaging scans (b value, 0 and 1,000 mm{sup 2}/s) were acquired before, during (mean 12 days), and 6-8 weeks after CRT. We compared the median apparent diffusion coefficients (ADCs) between responders and nonresponders and examined the associations with the Mandard tumor regression grade (TRG). The postoperative nodal status (ypN) was evaluated. The Mann-Whitney/Wilcoxon two-sample test was used to evaluate the relationships among the pretherapy ADCs, extramural vascular invasion, early percentage of increases in ADCs, and preoperative ADCs. Results: Low pretreatment ADCs (<1.0 Multiplication-Sign 10{sup -3}mm{sup 2}/s) were correlated with TRG 4 scores (p = .0011) and associated to extramural vascular invasion with ypN+ (85.7% positive predictive value for ypN+). During treatment, the mean percentage of increase in tumor ADC was significantly greater in the responders than in the nonresponders (p < .0001) and a >23% ADC increase had a 96.3% negative predictive value for TRG 4. In 9 of 16 complete responders, CRT-related tumor downsizing prevented ADC evaluations. The preoperative ADCs were significantly different (p = .0012) between the patients with and without downstaging (preoperative ADC {>=}1.4 Multiplication-Sign 10{sup -3}mm{sup 2}/s showed a positive and negative predictive value of 78.9% and 61.8%, respectively, for response assessment). The TRG 1 and TRG 2-4 groups were not significantly different. Conclusion: Diffusion-weighted magnetic resonance imaging seems to be a promising tool for monitoring the response to CRT.

Barbaro, Brunella, E-mail: bbarbaro@rm.unicatt.it [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Vitale, Renata; Valentini, Vincenzo; Illuminati, Sonia [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Vecchio, Fabio M. [Department of Pathology, Catholic University School of Medicine, Rome (Italy); Rizzo, Gianluca [Department of Surgery, Catholic University School of Medicine, Rome (Italy); Gambacorta, Maria Antonietta [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Coco, Claudio; Crucitti, Antonio; Persiani, Roberto; Sofo, Luigi [Department of Surgery, Catholic University School of Medicine, Rome (Italy); Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy)

2012-06-01T23:59:59.000Z

198

Magnetic Resonance Flow Velocity and Temperature Mapping of a Shape Memory Polymer Foam Device  

Science Conference Proceedings (OSTI)

Interventional medical devices based on thermally responsive shape memory polymer (SMP) are under development to treat stroke victims. The goals of these catheter-delivered devices include re-establishing blood flow in occluded arteries and preventing aneurysm rupture. Because these devices alter the hemodynamics and dissipate thermal energy during the therapeutic procedure, a first step in the device development process is to investigate fluid velocity and temperature changes following device deployment. A laser-heated SMP foam device was deployed in a simplified in vitro vascular model. Magnetic resonance imaging (MRI) techniques were used to assess the fluid dynamics and thermal changes associated with device deployment. Spatial maps of the steady-state fluid velocity and temperature change inside and outside the laser-heated SMP foam device were acquired. Though non-physiological conditions were used in this initial study, the utility of MRI in the development of a thermally-activated SMP foam device has been demonstrated.

Small IV, W; Gjersing, E; Herberg, J L; Wilson, T S; Maitland, D J

2008-10-29T23:59:59.000Z

199

Destabilization of the trapped electron mode by magnetic curvature drift resonances  

SciTech Connect

Electron curvature drift resonances, ignored in earlier work on the trapped-electron modes, are found to exert a strong destabilizing influence in the lower collision frequency range of these instabilities. Effects arising from ion temperature gradients, shear, and finite ion gyroradius are included with these vector nebla-drifts in the analysis, and the resultant eigenvalue equation is solved by numerical procedures rather than the commonly used perturbation techniques. For typical tokamak parameters the maximum growth rates are found to be increased over earlier estimates by roughly a factor of 4, and requirements on magnetic shear strength for stabilization are likewise more severe and very difficult to satisfy. For inverted density profiles, this new destabilizing effect is rendered ineffective, with the result that the modes can be stabilized for achievable values of shear provided the temperature gradients are not too severe. Estimates of the particle and thermal energy transport are given for both normal and inverted profiles. (auth)

Adam, J.C.; Tang, W.M.; Rutherford, P.H.

1975-12-01T23:59:59.000Z

200

Temperature dependence of magnetic susceptibility of nuclear matter: Lowest order constrained variational calculations  

Science Conference Proceedings (OSTI)

In this paper we study the magnetic susceptibility and other thermodynamic properties of the polarized nuclear matter at finite temperature using the lowest order constrained variational (LOCV) method employing the AV{sub 18} potential. Our results show a monotonic behavior for the magnetic susceptibility which indicates that the spontaneous transition to the ferromagnetic phase does not occur for this system.

Bigdeli, M. [Department of Physics, Zanjan University, P. O. Box 45195-313, Zanjan (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha, P. O. Box 55134-441, Maragha (Iran, Islamic Republic of); Bordbar, G. H. [Department of Physics, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha, P. O. Box 55134-441, Maragha (Iran, Islamic Republic of); Rezaei, Z. [Department of Physics, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of)

2009-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Isotopic imaging via nuclear resonance fluorescence with laser-based Thomson radiation  

DOE Patents (OSTI)

The present invention utilizes novel laser-based, high-brightness, high-spatial-resolution, pencil-beam sources of spectrally pure hard x-ray and gamma-ray radiation to induce resonant scattering in specific nuclei, i.e., nuclear resonance fluorescence. By monitoring such fluorescence as a function of beam position, it is possible to image in either two dimensions or three dimensions, the position and concentration of individual isotopes in a specific material configuration. Such methods of the present invention material identification, spatial resolution of material location and ability to locate and identify materials shielded by other materials, such as, for example, behind a lead wall. The foundation of the present invention is the generation of quasimonochromatic high-energy x-ray (100's of keV) and gamma-ray (greater than about 1 MeV) radiation via the collision of intense laser pulses from relativistic electrons. Such a process as utilized herein, i.e., Thomson scattering or inverse-Compton scattering, produces beams having diameters from about 1 micron to about 100 microns of high-energy photons with a bandwidth of .DELTA.E/E of approximately 10E.sup.-3.

Barty, Christopher P. J. (Hayward, CA); Hartemann, Frederic V. (San Ramon, CA); McNabb, Dennis P. (Alameda, CA); Pruet, Jason A. (Brentwood, CA)

2009-07-21T23:59:59.000Z

202

Search for magnetic dipole strength and giant spin-flip resonances in heavy nuclei. [120 to 200 MeV  

SciTech Connect

A description is given of the use of high-resolution (n,n) scattering and the (p,n) reaction as tools to investigate highly excited states, with emphasis on information pertaining to magnetic dipole strength and giant spin-flip resonances in heavy nuclei. It is shown how the ability to determine uniquely the spins and parities of resonances observed in neutron scattering has been instrumental to an understanding of the distribution of M1 strength in /sup 207/ /sup 208/Pb. Some recent results of (p,n) studies with intermediate energy protons are discussed. Energy systematics of the giant Gamow-Teller (GT) resonance as well as new ..delta..l = ..delta..S = 1 resonance with J/sup ..pi../ = (1,2)/sup -/ are presented. It is shown how the (p,n) reaction might be useful in locating M1 strength in heavy nuclei. 20 figures.

Horen, D.J.

1980-01-01T23:59:59.000Z

203

Nuclear Magnetism and Superconductivity: Investigations on Lithium and Rhodium.  

E-Print Network (OSTI)

??This thesis describes low temperature experiments on lithium. The experiments concentrate on investigating low temperature phase transitions of two subsystems in this metal: its nuclear (more)

Juntunen, Kirsi

2005-01-01T23:59:59.000Z

204

Nuclear magnetism and superconductivity : investigations on lithium and rhodium.  

E-Print Network (OSTI)

??This thesis describes low temperature experiments on lithium. The experiments concentrate on investigating low temperature phase transitions of two subsystems in this metal: its nuclear (more)

Juntunen, Kirsi

2005-01-01T23:59:59.000Z

205

On the Search for Nuclear Resonance Fluorescence Signatures of 235U and 238U above 3 MeV  

SciTech Connect

Nuclear resonance fluorescence is a physical process that provides an isotope-specific signature that could be used for the identification and characterization of materials. The technique involves the detection of prompt discrete-energy photons emitted from a sample that is exposed to MeV-energy photons. Potential applications of the technique range from detection of high explosives to characterization of special nuclear materials such as 235U. Pacific Northwest National Laboratory and Passport Systems have collaborated to conduct a pair of measurements to search for a nuclear resonance fluorescence response of 235U above 3 MeV and of 238U above 5 MeV using an 8 g sample of highly enriched uranium and a 90 g sample of depleted uranium. No new signatures were observed. The minimum detectable integrated cross section for 235U is presented.

Warren, Glen A.; Caggiano, Joseph A.; Bertozzi, William; Korbly, Steve; Ledoux, Robert; Park, William H.

2010-02-01T23:59:59.000Z

206

Fe K-edge X-ray resonant magnetic scattering from Ba(Fe1?xCox)2As2 superconductors  

SciTech Connect

We present an X-ray resonant magnetic scattering study at the Fe-K absorption edge of the BaFe2As2 compound. The energy spectrum of the resonant scattering, together with our calculation using the full-potential linear-augmented plane wave method with a local density functional suggests that the observed resonant scattering arises from electric dipole (E1) transitions. We discuss the role of Fe K-edge X-ray resonant magnetic scattering in understanding the relationship between the structure and the antiferromagnetic transition in the doped Ba(Fe1?xCox)2As2 superconductors.

Kim, Min Gyu; Kreyssig, Andreas; Lee, Yongbin; McQueeney, Robert J.; Harmon, Bruce N.; Goldman, Alan I.

2012-06-15T23:59:59.000Z

207

Sensing remote nuclear spins  

E-Print Network (OSTI)

Sensing single nuclear spins is a central challenge in magnetic resonance based imaging techniques. Although different methods and especially diamond defect based sensing and imaging techniques in principle have shown sufficient sensitivity, signals from single nuclear spins are usually too weak to be distinguished from background noise. Here, we present the detection and identification of remote single C-13 nuclear spins embedded in nuclear spin baths surrounding a single electron spins of a nitrogen-vacancy centre in diamond. With dynamical decoupling control of the centre electron spin, the weak magnetic field ~10 nT from a single nuclear spin located ~3 nm from the centre with hyperfine coupling as weak as ~500 Hz is amplified and detected. The quantum nature of the coupling is confirmed and precise position and the vector components of the nuclear field are determined. Given the distance over which nuclear magnetic fields can be detected the technique marks a firm step towards imaging, detecting and cont...

Zhao, Nan; Schmid, Berhard; Isoya, Junichi; Markham, Mathew; Twitchen, Daniel; Jelezko, Fedor; Liu, Ren-Bao; Fedder, Helmut; Wrachtrup, Jrg

2012-01-01T23:59:59.000Z

208

Respiratory motion of the heart: Implications for magnetic resonance coronary angiography  

Science Conference Proceedings (OSTI)

Magnetic resonance(MR) coronary imaging is susceptible to artifacts caused by motion of the heart. The purpose of this thesis was to study the respiratory motion of the coronary arteries and to use the results to develop strategies for improved MRimaging. The first section of the thesis describes a MR motion correction technique for objects undergoing a 3D affine transformation. The remainder of the thesis focuses on measuring the respiratory motion of the heart from free breathing x-ray angiograms. Stereo reconstruction methods are used to generate 3D models of the arteries from biplane angiograms. A method for tracking the motion of the arteries in a sequence of biplane images is presented next. The algorithm uses 3D regularizing constraints on the length changes of the arteries and on the spatial regularity of their motion. The algorithm was validated using a deforming vascular phantom. RMS 3D distance errors were measured between centerline models tracked in the x-ray images and gold-standard models derived from a gated 3D MR acquisition. The mean error was 0.690.06? mm for four different orientations of the x-ray system. The motion field recovered from free breathing angiograms is a combination of the cardiac contraction and respiratory motion of the heart. A cardiac respiratory parametric model is formulated to decompose the field into independent cardiac and respiratory components. Results are presented for ten patients imaged during spontaneous tidal breathing. For all patients

Guy Shechter

2004-01-01T23:59:59.000Z

209

Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging  

DOE Patents (OSTI)

Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.

Hu, Jian Zhi (Richland, WA); Sears, Jr., Jesse A. (Kennewick, WA); Hoyt, David W. (Richland, WA); Wind, Robert A. (Kennewick, WA)

2009-05-19T23:59:59.000Z

210

Radiation-Induced Damage to Microstructure of Parotid Gland: Evaluation Using High-Resolution Magnetic Resonance Imaging  

SciTech Connect

Purpose: To elucidate the radiation-induced damage to the microstructure of the parotid gland using high-resolution magnetic resonance imaging. Methods and Materials: High-resolution magnetic resonance imaging of the parotid gland was performed before radiotherapy (RT) and during the RT period or {<=}3 weeks after RT completion for 12 head-and-neck cancer patients using a 1.5-T scanner with a microscopy coil. The maximal cross-sectional area of the gland was evaluated, and changes in the internal architecture of the gland were assessed both visually and quantitatively. Results: Magnetic resonance images were obtained at a median parotid gland dose of 36 Gy (range, 11-64). According to the quantitative analysis, the maximal cross-sectional area of the gland was reduced, the width of the main duct was narrowed, and the intensity ratio of the main duct lumen to background was significantly decreased after RT (p <.0001). According to the visual assessment, the width of the main duct tended to narrow and the contrast of the duct lumen tended to be decreased, but no significant differences were noted. The visibility of the duct branches was unclear in 10 patients (p = .039), and the septum became dense in 11 patients (p = .006) after RT. Conclusion: High-resolution magnetic resonance imaging is a noninvasive method of evaluating radiation-induced changes to the internal architecture of the parotid gland. Morphologic changes in the irradiated parotid gland were demonstrated during the RT course even when a relatively small dose was delivered to the gland.

Kan, Tomoko, E-mail: tkan@grape.med.tottori-u.ac.j [Department of Radiology, Tottori University Faculty of Medicine, Yonago, Tottori (Japan); Kodani, Kazuhiko; Michimoto, Koichi; Fujii, Shinya; Ogawa, Toshihide [Department of Radiology, Tottori University Faculty of Medicine, Yonago, Tottori (Japan)

2010-07-15T23:59:59.000Z

211

Fully relativistic calculation of nuclear magnetic shieldings and indirect nuclear spin-spin couplings in group-15 and -16 hydrides  

Science Conference Proceedings (OSTI)

Fully relativistic calculations of the isotropic and anisotropic parts of both indirect nuclear spinspin couplings 1 J(X- H ) and 2 J( H-H ) and nuclear magnetic shieldings ?(X) and ?(H) for the group-15 and -16 hydrides are presented. Relativistic calculations were performed with DiracFock wave functions and the random phase approximation method. Results are compared to its nonrelativistic counterpart. Paramagnetic and diamagnetic contributions to the nuclear magnetic shielding constants are also reported. We found very large relativistic corrections to both properties in the sixth-row hydrides ( BiH 3 and PoH 2 ). Our calculations of the relativistic corrections to the isotropic part of ? at the heavy nucleus X show that it is roughly proportional to Z 3.2 in both series of molecules. Paramagnetic term ? p is more sensitive to the effects of relativity than the diamagnetic one ? d even though both have a behavior proportional to third power of the nuclear charge Z.

Sergio S. Gomez; Rodolfo H. Romero; Gustavo A. Aucar

2002-01-01T23:59:59.000Z

212

Transmission Nuclear Resonance Fluorescence Measurements of 238U in Thick Targets  

E-Print Network (OSTI)

thickness of a nuclear fuel assembly. The experimental dataproperties similar to a nuclear fuel assembly so that thein ? bjquiter@lbl.gov nuclear fuel could be tested. In this

Quiter, Brian J.

2011-01-01T23:59:59.000Z

213

Effect of Gold Marker Seeds on Magnetic Resonance Spectroscopy of the Prostate  

SciTech Connect

Purpose: Magnetic resonance stereoscopic imaging (MRSI) of the prostate is an emerging technique that may enhance targeting and assessment in radiotherapy. Current practices in radiotherapy invariably involve image guidance. Gold seed fiducial markers are often used to perform daily prostate localization. If MRSI is to be used in targeting prostate cancer and therapy assessment, the impact of gold seeds on MRSI must be investigated. The purpose of this study was to quantify the effects of gold seeds on the quality of MRSI data acquired in phantom experiments. Methods and Materials: A cylindrical plastic phantom with a spherical cavity 10 centimeters in diameter wss filled with water solution containing choline, creatine, and citrate. A gold seed fiducial marker was put near the center of the phantom mounted on a plastic stem. Spectra were acquired at 1.5 Tesla by use of a clinical MRSI sequence. The ratios of choline + creatine to citrate (CC/Ci) were compared in the presence and absence of gold seeds. Spectra in the vicinity of the gold seed were analyzed. Results: The maximum coefficient of variation of CC/Ci induced by the gold seed was found to be 10% in phantom experiments at 1.5 T. Conclusion: MRSI can be used in prostate radiotherapy in the presence of gold seed markers. Gold seeds cause small effects (in the order of the standard deviation) on the ratio of the metabolite's CC/Ci in the phantom study done on a 1.5-T scanner. It is expected that gold seed markers will have similar negligible effect on spectra from prostate patients. The maximum of 10% of variation in CC/Ci found in the phantom study also sets a limit on the threshold accuracy of CC/Ci values for deciding whether the tissue characterized by a local spectrum is considered malignant and whether it is a candidate for local boost in radiotherapy dose.

Hossain, Murshed, E-mail: Murshed.Hossain@fccc.edu [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Schirmer, Timo [Global MR Applied Science Laboratory, GE Healthcare, Munich (Germany); Richardson, Theresa; Chen, Lili; Buyyounouski, Mark K.; Ma Changming [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)

2012-05-01T23:59:59.000Z

214

Magnetic Resonance Imaging-Guided Osseous Biopsy in Children With Chronic Recurrent Multifocal Osteomyelitis  

SciTech Connect

Purpose: To report the safety and diagnostic performance of magnetic resonance (MRI)-guided core biopsy of osseous lesions in children with chronic recurrent multifocal osteomyelitis (CRMO) that were visible on MRI but were occult on radiography and computed tomography (CT). Materials and Methods: A retrospective analysis of MRI-guided osseous biopsy performed in seven children (four girls and three boys; mean age 13 years (range 11 to 14) with CRMO was performed. Indication for using MRI guidance was visibility of lesions by MRI only. MRI-guided procedures were performed with 0.2-Tesla (Magnetom Concerto; Siemens, Erlangen, Germany; n = 5) or 1.5-T (Magnetom Espree; Siemens; n = 2) open MRI systems. Core needle biopsy was obtained using an MRI-compatible 4-mm drill system. Conscious sedation or general anesthesia was used. Parameters evaluated were lesion visibility, technical success, procedure time, complications and microbiology, cytology, and histopathology findings. Results: Seven of seven (100%) targeted lesions were successfully visualized and sampled. All obtained specimens were sufficient for histopathological analysis. Length of time of the procedures was 77 min (range 64 to 107). No complications occurred. Histopathology showed no evidence of malignancy, which was confirmed at mean follow-up of 50 months (range 28 to 78). Chronic nonspecific inflammation characteristic for CRMO was present in four of seven (58%) patients, and edema with no inflammatory cells was found in three of seven (42%) patients. There was no evidence of infection in any patient. Conclusion: MRI-guided osseous biopsy is a safe and accurate technique for the diagnosis of pediatric CRMO lesions that are visible on MRI only.

Fritz, Jan, E-mail: jfritz9@jhmi.edu [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science (United States); Tzaribachev, Nikolay [University Children's Hospital, Eberhard-Karls-University Tuebingen, Division of Pediatric Rheumatology (Germany); Thomas, Christoph [Eberhard-Karls-University Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Wehrmann, Manfred [Eberhard-Karls-University Tuebingen, Department of Pathology (Germany); Horger, Marius S. [Eberhard-Karls-University Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Carrino, John A. [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science (United States); Koenig, Claudius W.; Pereira, Philippe L. [Eberhard-Karls-University Tuebingen, Department of Diagnostic and Interventional Radiology (Germany)

2012-02-15T23:59:59.000Z

215

Dynamic Contrast-Enhanced Magnetic Resonance Imaging of the Metastatic Potential of Melanoma Xenografts  

SciTech Connect

Purpose: Gadolinium diethylene-triamine penta-acetic acid (Gd-DTPA)-based dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has been suggested as a useful noninvasive method for characterizing the physiologic microenvironment of tumors. In the present study, we investigated whether Gd-DTPA-based DCE-MRI has the potential to provide biomarkers for hypoxia-associated metastatic dissemination. Methods and Materials: C-10 and D-12 melanoma xenografts were used as experimental tumor models. Pimonidazole was used as a hypoxia marker. A total of 60 tumors were imaged, and parametric images of K{sup trans} (volume transfer constant of Gd-DTPA) and v{sub e} (fractional distribution volume of Gd-DTPA) were produced by pharmacokinetic analysis of the DCE-MRI series. The host mice were killed immediately after DCE-MRI, and the primary tumor and the lungs were resected and prepared for histologic assessment of the fraction of pimonidazole-positive hypoxic tissue and the presence of lung metastases, respectively. Results: Metastases were found in 11 of 26 mice with C-10 tumors and 14 of 34 mice with D-12 tumors. The primary tumors of the metastatic-positive mice had a greater fraction of hypoxic tissue (p = 0.00031, C-10; p < 0.00001, D-12), a lower median K{sup trans} (p = 0.0011, C-10; p < 0.00001, D-12), and a lower median v{sub e} (p = 0.014, C-10; p = 0.016, D-12) than the primary tumors of the metastatic-negative mice. Conclusions: These findings support the clinical attempts to establish DCE-MRI as a method for providing biomarkers for tumor aggressiveness and suggests that primary tumors characterized by low K{sup trans} and low v{sub e} values could have a high probability of hypoxia-associated metastatic spread.

Ovrebo, Kirsti Marie; Ellingsen, Christine; Galappathi, Kanthi [Group of Radiation Biology and Tumor Physiology, Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway); Rofstad, Einar K., E-mail: einar.k.rofstad@rr-research.no [Group of Radiation Biology and Tumor Physiology, Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway)

2012-05-01T23:59:59.000Z

216

Image-Based Monitoring of Magnetic Resonance-Guided Thermoablative Therapies for Liver Tumors  

SciTech Connect

Minimally invasive treatment options for liver tumor therapy have been increasingly used during the last decade because their benefit has been proven for primary and inoperable secondary liver tumors. Among these, radiofrequency ablation has gained widespread consideration. Optimal image-guidance offers precise anatomical information, helps to position interventional devices, and allows for differentiation between already-treated and remaining tumor tissue. Patient safety and complete ablation of the entire tumor are the overriding objectives of tumor ablation. These may be achieved most elegantly with magnetic resonance (MR)-guided therapy, where monitoring can be performed based on precise soft-tissue imaging and additional components, such as diffusion-weighted imaging and temperature mapping. New MR scanner types and newly developed sequence techniques have enabled MR-guided intervention to move beyond the experimental phase. This article reviews the current role of MR imaging in guiding radiofrequency ablation. Signal characteristics of primary and secondary liver tumors are identified, and signal alteration during therapy is described. Diffusion-weighted imaging (DWI) and temperature mapping as special components of MR therapy monitoring are introduced. Practical information concerning coils, sequence selection, and parameters, as well as sequence gating, is given. In addition, sources of artifacts are identified and techniques to decrease them are introduced, and the characteristic signs of residual tumor in T1-, T2-, and DWI are described. We hope to enable the reader to choose MR sequences that allow optimal therapy monitoring depending on the initial signal characteristics of the tumor as well as its size and location in the liver.

Rempp, Hansjoerg, E-mail: hansjoerg.rempp@med.uni-tuebingen.de; Clasen, Stephan [Eberhard Karls University of Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Pereira, Philippe L. [SLK-Kliniken, Clinic for Radiology, Nuclear Medicine, and Minimal Invasive Therapies (Germany)

2012-12-15T23:59:59.000Z

217

Magnetic Field Generation in Planets and Satellites by Natural Nuclear Fission Reactors  

E-Print Network (OSTI)

One of the most fundamental problems in physics has been to understand the nature of the mechanism that generates the geomagnetic field and the magnetic fields of other planets and satellites. For decades, the dynamo mechanism, thought to be responsible for generating the geomagnetic field and other planetary magnetic fields, has been ascribed to convection in each planet's iron-alloy core. Recently, I described the problems inherent in Earth-core convection and proposed instead that the geomagnetic field is produced by a dynamo mechanism involving convection, not in the fluid core, but in the electrically conductive, fluid, fission-product sub-shell of a natural nuclear fission reactor at the center of the Earth, called the georeactor. Here I set forth in detail the commonality in the Solar System of the matter like that of the inside of the Earth, which is my basis for generalizing the concept of planetary magnetic field generation by natural planetocentric nuclear fission reactors.

J. Marvin Herndon

2007-07-27T23:59:59.000Z

218

Spinodal instabilities and the distillation effect in nuclear matter under strong magnetic fields  

E-Print Network (OSTI)

We study the effect of strong magnetic fields, of the order of $10^{18}$-$10^{19}$ G, on the instability region of nuclear matter at subsaturation densities. Relativistic nuclear models both with constant couplings and with density dependent parameters are considered. It is shown that a strong magnetic field can have large effects on the instability regions giving rise to bands of instability and wider unstable regions. As a consequence we predict larger transition densities at the inner edge of the crust of compact stars with strong magnetic field. The direction of instability gives rise to a very strong distillation effect if the last Landau level is only partially filled. However, for almost completed Landau levels an anti-distillation effect may occur.

A. Rabhi; C. Providencia; J. Da Providencia

2008-10-19T23:59:59.000Z

219

Spinodal instabilities and the distillation effect in nuclear matter under strong magnetic fields  

Science Conference Proceedings (OSTI)

We study the effect of strong magnetic fields, of the order of 10{sup 18}-10{sup 19} G, on the instability region of nuclear matter at subsaturation densities. Relativistic nuclear models both with constant couplings and with density-dependent parameters are considered. It is shown that a strong magnetic field can have large effects on the instability regions giving rise to bands of instability and wider unstable regions. As a consequence, we predict larger transition densities at the inner edge of the crust of compact stars with strong magnetic fields. The direction of instability gives rise to a very strong distillation effect if the last Landau level is only partially filled. However, for almost completed Landau levels, an antidistillation effect may occur.

Rabhi, A. [Centro de Fisica Computacional, Department of Physics, University of Coimbra, P-3004-516 Coimbra (Portugal); Laboratoire de Physique de la Matiere Condensee, Faculte des Sciences de Tunis, Campus Universitaire, Le Belvedere-1060 (Tunisia); Providencia, C.; Providencia, J. Da [Centro de Fisica Computacional, Department of Physics, University of Coimbra, P-3004-516 Coimbra (Portugal)

2009-01-15T23:59:59.000Z

220

Table of Nuclear Magnetic Dipole and Electric Quadrupole Moments  

E-Print Network (OSTI)

Ma25 ZP A327 157 (87) 4492 295 ps 5- +2.6(5) IPAD 1974He13 PR C10 919 (74) 20 Ca 41 0 1.0x10 5 y 7 Research NP Nuclear Physics NuoC Nuovo Cimento NuoCL Nuovo Cimento Letters OptL Optics Letters ORNL Oak) +0.822567(3) [2H] N ZNat 23a 1202 (68)/PL A25 440 (67)/ ORNL-1775 (54) -0.00083(8) st [7Li] MB,R CPL

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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221

Dynamics of nuclear polarization in InGaAs quantum dots in a transverse magnetic field  

SciTech Connect

The time-resolved Hanle effect is examined for negatively charged InGaAs/GaAs quantum dots. Experimental data are analyzed by using an original approach to separate behavior of the longitudinal and transverse components of nuclear polarization. This made it possible to determine the rise and decay times of each component of nuclear polarization and their dependence on transverse magnetic field strength. The rise and decay times of the longitudinal component of nuclear polarization (parallel to the applied field) were found to be almost equal (approximately 5 ms). An analysis of the transverse component of nuclear polarization shows that the corresponding rise and decay times differ widely and strongly depend on magnetic field strength, increasing from a few to tens of milliseconds with an applied field between 20 and 100 mT. Current phenomenological models fail to explain the observed behavior of nuclear polarization. To find an explanation, an adequate theory of spin dynamics should be developed for the nuclear spin system of a quantum dot under conditions of strong quadrupole splitting.

Verbin, S. Yu., E-mail: syuv54@mail.ru; Gerlovin, I. Ya.; Ignatiev, I. V., E-mail: ivan_ignatiev@mail.ru; Kuznetsova, M. S.; Cherbunin, R. V. [St. Petersburg State University, Spin Optics Laboratory (Russian Federation); Flisinski, K.; Yakovlev, D. R.; Bayer, M. [Technische Universitaet Dortmund (Germany)

2012-04-15T23:59:59.000Z

222

MAGNETIC RESONANCE ELECTRICAL IMPEDANCE TOMOGRAPHY (MR-EIT): A new technique for high resolution conductivity imaging  

E-Print Network (OSTI)

to a conductor generates a constant magnetic field with flux density jB r . If the current carrying conductor potentials and the magnetic fields produced by the probing current are measured. Surface potentials and the point spread function is not space invariant. On the other hand, magnetic field and electrical current

Eyüboðlu, Murat

223

Tumor Volume Reduction Rate Measured by Magnetic Resonance Volumetry Correlated With Pathologic Tumor Response of Preoperative Chemoradiotherapy for Rectal Cancer  

SciTech Connect

Purpose: To determine whether the tumor volume reduction rate (TVRR) measured using three-dimensional region-of-interest magnetic resonance volumetry correlates with the pathologic tumor response after preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer. Methods and Materials: The study included 405 patients with locally advanced rectal cancer (cT3-T4) who had undergone preoperative CRT and radical proctectomy. The tumor volume was measured using three-dimensional region-of-interest magnetic resonance volumetry before and after CRT but before surgery. We analyzed the correlation between the TVRR and the pathologic tumor response in terms of downstaging and tumor regression grade (TRG). Downstaging was defined as ypStage 0-I (ypT0-T2N0M0), and the TRG proposed by Dworak et al. was used. Results: The mean TVRR was 65.0% {+-} 22.3%. Downstaging and complete regression occurred in 167 (41.2%) and 58 (14.3%) patients, respectively. The TVRRs according to ypT classification (ypT0-T2 vs. ypT3-T4), ypN classification (ypN0 vs. ypN1-N2), downstaging (ypStage 0-I vs. ypStage II-III), good regression (TRG 3-4 vs. TRG 1-2), and complete regression (TRG 4 vs. TRG 1-3) were all significantly different (p <.05). When the TVRR was categorized into three groups (<60%, 60-80%, and >80%), the rates of ypT0-T2, ypN0, downstaging, and good regression were all significantly greater for patients with a TVRR of {>=}60%, as was the complete regression rate for patients with a TVRR >80% (p <.05). Conclusion: The TVRR measured using three-dimensional region-of-interest magnetic resonance volumetry correlated significantly with the pathologic tumor response in terms of downstaging and TRG after preoperative CRT for locally advanced rectal cancer.

Yeo, Seung-Gu [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Radiation Oncology, Soon Chun Hyang University College of Medicine, Cheonan (Korea, Republic of); Kim, Dae Yong, E-mail: radiopiakim@hanmail.ne [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Kim, Tae Hyun [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Jung, Kyung Hae; Hong, Yong Sang [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Medical Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Chang, Hee Jin; Park, Ji Won [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Lim, Seok-Byung [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Colon and Rectal Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Hyo Seong [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Jeong, Seung-Yong [Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Surgery, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2010-09-01T23:59:59.000Z

224

Magnetic Resonance-Based Treatment Planning for Prostate Intensity-Modulated Radiotherapy: Creation of Digitally Reconstructed Radiographs  

SciTech Connect

Purpose: To develop a technique to create magnetic resonance (MR)-based digitally reconstructed radiographs (DRR) for initial patient setup for routine clinical applications of MR-based treatment planning for prostate intensity-modulated radiotherapy. Methods and Materials: Twenty prostate cancer patients' computed tomography (CT) and MR images were used for the study. Computed tomography and MR images were fused. The pelvic bony structures, including femoral heads, pubic rami, ischium, and ischial tuberosity, that are relevant for routine clinical patient setup were manually contoured on axial MR images. The contoured bony structures were then assigned a bulk density of 2.0 g/cm{sup 3}. The MR-based DRRs were generated. The accuracy of the MR-based DDRs was quantitatively evaluated by comparing MR-based DRRs with CT-based DRRs for these patients. For each patient, eight measuring points on both coronal and sagittal DRRs were used for quantitative evaluation. Results: The maximum difference in the mean values of these measurement points was 1.3 {+-} 1.6 mm, and the maximum difference in absolute positions was within 3 mm for the 20 patients investigated. Conclusions: Magnetic resonance-based DRRs are comparable to CT-based DRRs for prostate intensity-modulated radiotherapy and can be used for patient treatment setup when MR-based treatment planning is applied clinically.

Chen, Lili [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)]. E-mail: lili.chen@fccc.edu; Nguyen, Thai-Binh [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Jones, Elan [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Chen Zuoqun [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Luo Wei [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Wang Lu [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Price, Robert A. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Pollack, Alan [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Ma, C.-M. Charlie [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)

2007-07-01T23:59:59.000Z

225

Resonant nuclear scattering of synchrotron radiation: Detector development and specular scattering from a thin layer of {sup 57}Fe  

Science Conference Proceedings (OSTI)

This thesis explores resonant nudear scattering of synchrotron radiation. An introductory chapter describes some useful concepts, such as speedup and coherent enhancement, in the context of some basic physical principles. Methods of producing highly monochromatic synchrotron beams usmg either electronic or nuclear scattering are also discussed. The body of the thesis concentrates on detector development and specular scattering from iynthetic layered materials. A detector employing n-dcrochannel plate electron multipliers is shown to have good ({approximately}50%) effidency for detecting 14.4 key x-rays incident at small ({approximately}0.5 degree) grazing angles onto Au or CsI photocathodes. However, being complicated to use, it was replaced with a large area (>=lan2) avalanche photodiode (APD) detector. The APD`s are simpler to use and have comparable (30--70%) efficiencies at 14.4 key, subnanosecond time resolution, large dynan-dc range (usable at rates up to {approximately}10{sup 8} photons/second) and low (<{approximately}0.01 cts/sec) background rates. Maxwell`s equations are used to derive the specular x-ray reflectivity of layered materials with resonant transitions and complex polarization dependencies. The effects of interfadal roughness are treated with some care, and the distorted wave Born approximation (DWBA) used to describe electronic scattering is generalized to the nuclear case. The implications of the theory are discussed in the context of grazing incidence measurements with emphasis on the kinematic and dynamical aspects of the scattering.

Baron, A.Q.R.

1995-04-01T23:59:59.000Z

226

Magnetic-resonance and thermophysical studies of the magnetic phase diagram for a GdFe{sub 2.1}Ga{sub 0.9}(BO{sub 3}){sub 4} single crystal  

Science Conference Proceedings (OSTI)

The antiferromagnetic resonance, heat capacity, magnetic properties, and magnetic phase diagram of a GdFe{sub 3}(BO{sub 3}){sub 4} crystal in which some of the iron ions were substituted by diamagnetic gallium ions have been investigated. It has been found that the Neel temperature upon diamagnetic substitution decreased to 17 K compared to 38 K in the unsubstituted crystal. The effective exchange and anisotropy fields for GdFe{sub 2.1}Ga{sub 0.9}(BO{sub 3}){sub 4} have been estimated from the field dependences of magnetization and resonance measurements. The magnetic phase diagram of the crystal has been constructed from magnetic and resonance measurements. In GdFe{sub 2.1}Ga{sub 0.9}(BO{sub 3}){sub 4}, there is no spontaneous reorientation and, in the absence of a magnetic field, the crystal remains an easy-axis one in the entire domain of magnetic ordering. The critical field of the reorientation transition to an induced easy-plane state in a magnetic field along the trigonal axis has been found to increase compared to that in the unsubstituted crystal.

Pankrats, A. I.; Petrakovskii, G. A.; Tugarinov, V. I., E-mail: vit@iph.krasn.ru; Kartashev, A. V.; Temerov, V. L. [Russian Academy of Science, Siberian Branch, Kirensky Institute of Physics (Russian Federation)

2011-09-15T23:59:59.000Z

227

Effect of the Wood-Saxon nuclear distribution on the chiral magnetic field in Relativistic Heavy-ion Collisions  

E-Print Network (OSTI)

The formation of the QCD vacuum with nonzero winding number $Q_w$ during relativistic heavy-ion collisions breaks the parity and charge-parity symmetry. A new kind of field configuration can separate charge in the presence of a background magnetic field-the "chiral magnetic effect". The strong magnetic field and the QCD vacuum can both completely be produced in the noncentral nuclear-nuclear collision. Basing on the theory of Kharzeev,Mclerran and Warringa, we use the Wood-Saxon nucleon distribution to replace that of the uniform distribution to improve the magnetic field calculation method of the noncentral collision. The chiral magnetic field distribution at LHC(Large Hadron Collider) energy regions are predicted. We also consider the contributions to the magnetic field of the total charge given by the produced quarks.

Yu-Jun Mo; Sheng-Qin Feng; Ya-Fei Shi

2013-08-20T23:59:59.000Z

228

Dynamic T{sub 2}-mapping during magnetic resonance guided high intensity focused ultrasound ablation of bone marrow  

Science Conference Proceedings (OSTI)

Focal bone tumor treatments include amputation, limb-sparing surgical excision with bone reconstruction, and high-dose external-beam radiation therapy. Magnetic resonance guided high intensity focused ultrasound (MR-HIFU) is an effective non-invasive thermotherapy for palliative management of bone metastases pain. MR thermometry (MRT) measures the proton resonance frequency shift (PRFS) of water molecules and produces accurate (<1 Degree-Sign C) and dynamic (<5s) thermal maps in soft tissues. PRFS-MRT is ineffective in fatty tissues such as yellow bone marrow and, since accurate temperature measurements are required in the bone to ensure adequate thermal dose, MR-HIFU is not indicated for primary bone tumor treatments. Magnetic relaxation times are sensitive to lipid temperature and we hypothesize that bone marrow temperature can be determined accurately by measuring changes in T{sub 2}, since T{sub 2} increases linearly in fat during heating. T{sub 2}-mapping using dual echo times during a dynamic turbo spin-echo pulse sequence enabled rapid measurement of T{sub 2}. Calibration of T{sub 2}-based thermal maps involved heating the marrow in a bovine femur and simultaneously measuring T{sub 2} and temperature with a thermocouple. A positive T{sub 2} temperature dependence in bone marrow of 20 ms/ Degree-Sign C was observed. Dynamic T{sub 2}-mapping should enable accurate temperature monitoring during MR-HIFU treatment of bone marrow and shows promise for improving the safety and reducing the invasiveness of pediatric bone tumor treatments.

Waspe, Adam C.; Looi, Thomas; Mougenot, Charles; Amaral, Joao; Temple, Michael; Sivaloganathan, Siv; Drake, James M. [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada); Philips Healthcare Canada, Markham, ON, L6C 2S3 (Canada); Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada); Department of Applied Mathematics, University of Waterloo, Waterloo, ON, N2L 3G1 (Canada); Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada)

2012-11-28T23:59:59.000Z

229

A high field solid-state nuclear magnetic resonance experimental study for clay and shale swelling.  

E-Print Network (OSTI)

??The development of the shale resources faces many problems related to their complex structure and challenging conditions. Drilling and fracturing operations suffer from the swelling (more)

Alzahrani, Mohammed S.

2013-01-01T23:59:59.000Z

230

Models of Chemical Structure and Dynamics via Nuclear Magnetic Resonance and Ab Initio Computational Chemistry  

E-Print Network (OSTI)

Resolution NMR Theory and Chemical Application ; 3rd ed. ,Methods. In Encyclopedia of Chemical Physics and PhysicalGROUPS ON THE PHYSICAL AND CHEMICAL BEHAVIOR OF CINCHONA

Lai, Jinfeng

2009-01-01T23:59:59.000Z

231

Nuclear Magnetic Resonance and Biochemical Investigations of Environmental Changes on Structure and Function of Subtilisins  

E-Print Network (OSTI)

Sharma S, Gupta MN. 2004. Biodiesel Preparation by Lipase-of the current state of biodiesel production using enzymatic

Liszka, Michael Joseph

2012-01-01T23:59:59.000Z

232

Enhanced oil recovery through water imbibition in fractured reservoirs using Nuclear Magnetic Resonance.  

E-Print Network (OSTI)

??Conventional waterflooding methods of oil recovery are difficult to apply when reservoirs show evidence of natural fractures, because injected water advances through paths of high (more)

Hervas Ordonez, Rafael Alejandro

2012-01-01T23:59:59.000Z

233

Nuclear magnetic resonance of laser-polarized noble gases in molecules, materials and organisms  

E-Print Network (OSTI)

r I- t of silica aerogels by Xe-129 NMR spectroscopy andcatalysts, ceramics, aerogels, food products, and antiquatedxenon penetration within an aerogel sample as a function of

Goodson, B.M.

2010-01-01T23:59:59.000Z

234

The use of spectroscopic techniques (especially phosphorus-31 nuclear magnetic resonance [31  

E-Print Network (OSTI)

the apparent environmental problems. Spent mushroom compost (high fungal content) was applied to soil at a rate replaced by transplanting strawberry seedlings in plugs containing compost colonised by a mixture of bacteria, fungi and their respective consumers. This compost promoted the establishment of a complex food

Sparks, Donald L.

235

Nuclear Magnetic Resonance and Biochemical Investigations of Environmental Changes on Structure and Function of Subtilisins  

E-Print Network (OSTI)

transesteri?cations for biofuel production, which has beendown costs and make biofuel production more economicallytemperatures for biofuel production. For example, three

Liszka, Michael Joseph

2012-01-01T23:59:59.000Z

236

The hydration of reactive cement-in-polymer dispersions studied by nuclear magnetic resonance  

Science Conference Proceedings (OSTI)

The behaviour of two novel cement-in-polymer (c/p) dispersions, namely cement-in-poly(vinyl acetate) and cement-in-poly(vinyl alcohol) upon exposure to water at room temperature was investigated by a combination of various NMR methods. The swelling, cracking, and the water ingress were monitored non-destructively using {sup 1}H single point imaging. The hydration of the cement matrix was investigated using {sup 29}Si NMR whilst {sup 13}C CPMAS NMR spectra allowed the quantification of the kinetics of the hydrolysis reaction of poly(vinyl acetate) into poly(vinyl alcohol). The polymer controls the rate of water ingress and swelling which in turn determines the behaviour of the c/p dispersions upon exposure to water. For the cement-in-poly(vinyl alcohol), the rates of water ingress and swelling are much faster than the hydration of the clinker whilst for the cement-in-poly(vinyl acetate) the slow rates of the two processes allow the formation of a cementious matrix which assures the stability of the sample.

Olaru, A.M. [Institut fuer Technische und Makromolekulare Chemie, RWTH Aachen University, Templergraben 55, 52056 Aachen (Germany); Weichold, O. [DWI an der RWTH Aachen, e. V., Pauwelsstrasse 8, 52056 Aachen (Germany); Adams, A., E-mail: aadams@mc.rwth-aachen.de [Institut fuer Technische und Makromolekulare Chemie, RWTH Aachen University, Templergraben 55, 52056 Aachen (Germany)

2011-11-15T23:59:59.000Z

237

Method for nuclear magnetic resonance imaging using deuterum as a contrast agent  

DOE Patents (OSTI)

A method for in vivo NMR imaging of the blood vessels and organs of a patient characterized by using a dark dye-like imaging substance consisting essentially of a stable, high-purity concentration of D.sub.2 O in a solution with water.

Kehayias, Joseph J. (Chestnut Hill, MA); Joel, Darrel D. (Setauket, NY); Adams, William H. (Eastport, NY); Stein, Harry L. (Glen Head, NY)

1990-01-01T23:59:59.000Z

238

Final Report: Nuclear Magnetic Resonance (NMR) of Catalysis, September 1, 1993 - December 31, 1998  

DOE Green Energy (OSTI)

On going work concerns the mechanisms of methanol conversion to hydrocarbons on zeolite solid acids.

Haw, James F.

1998-12-31T23:59:59.000Z

239

Fast Magnetic Resonance Imaging via Adaptive Broadband Encoding of the MR Signal Content  

E-Print Network (OSTI)

signal is radiated from the sample and decays over time both via the return of the sample's magnetization decays after sample excitation. Relaxation times of the order of 1sec in human tissue make the process studies where a continu- ous series of images is required, for example in contrast bolus tracking

Edelman, Alan

240

JOURNAL OF MAGNETIC RESONANCE 54, 170-173 ( 1983) The l-l Hard Pulse:A Simple and Effective Method of Water  

E-Print Network (OSTI)

JOURNAL OF MAGNETIC RESONANCE 54, 170- 173 ( 1983) The l-l Hard Pulse:A Simple and Effective Method the long Alexander (I) and 2-l-4 Redfield (2) pulses and the hard time-shared Redfield (3, 4), jump-return (5), and 1-2-1 pulses (6). The hard time-shared pulse sequences have the significant advantage over

Clore, G. Marius

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241

Using nitrogen-14 nuclear quadrupole resonance and electric field gradient information for the study of radiation effects  

Science Conference Proceedings (OSTI)

Nitrogen-14 nuclear quadrupole resonance (NQR) was used in an attempt to detect the effects of ionizing radiation on organic material. Previously reported resonances for urea were detected at 2,913.32 {+-} 0.01 kHz and 2,347.88 {+-} 0.08 kHz with associated T{sub 2}* values 780 {+-} 20 {micro}s and 523 {+-} 24 {micro}s, respectively. The previously unreported {nu}{sub {minus}} line for urea-d{sup 4} was detected at 2,381 {+-} 0.04 Khz and used to determine accurately for the first time the values for the nuclear quadrupole coupling constant {chi} (3,548.74 {+-} 0.03 kHz) and the asymmetry parameter {eta} (0.31571 {+-} 0.00007) for urea-d{sup 4}. The inverse linewidth parameter T{sub 2}* for {nu}{sub +} was measured at 928 {+-} 23 {micro}s and for {nu}{sub {minus}} at 721 {+-} 12 {micro}s. Townes and Dailey analysis was performed and urea-d{sup 4} exhibits a 0.004 increase in lone pair electronic density and a slight decrease in N-H bond electronic density, as compared to urea, probably due to the mass difference. A relationship is proposed, referred to as NQR linewidth analysis, between the dynamic spin relaxation times T{sub 2} and T{sub 2}* and the widths of the distributions of the NQR parameters. Linewidth analysis is presented as a tool for possible use in future NQR work in all area, not just radiation effects. This relationship is tested using sodium nitrite T{sub 2} and T{sub 2}* values for {nu}{sub {minus}} and {nu}{sub {minus}} as a function of temperature.

Iselin, L.H.

1995-12-01T23:59:59.000Z

242

MOA: Magnetic Field Oscillating Amplified Thruster and its Application for Nuclear Electric and Thermal Propulsion  

Science Conference Proceedings (OSTI)

More than 60 years after the later Nobel laureate Hannes Alfven had published a letter stating that oscillating magnetic fields can accelerate ionised matter via magneto-hydrodynamic interactions in a wave like fashion, the technical implementation of Alfven waves for propulsive purposes has been proposed, patented and examined for the first time by a group of inventors. The name of the concept, utilising Alfven waves to accelerate ionised matter for propulsive purposes, is MOA - Magnetic field Oscillating Amplified thruster. Alfven waves are generated by making use of two coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system. It is this deformation that generates Alfven waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system. Based on computer simulations, which were conducted to get a first estimate on the performance of the system, MOA is a highly flexible propulsion system, whose performance parameters might easily be adapted, by changing the mass flow and/or the power level. As such the system is capable to deliver a maximum specific impulse of 13116 s (12.87 mN) at a power level of 11.16 kW, using Xe as propellant, but can also be attuned to provide a thrust of 236.5 mN (2411 s) at 6.15 kW of power. While space propulsion is expected to be the prime application for MOA and is supported by numerous applications such as Solar and/or Nuclear Electric Propulsion or even as an 'afterburner system' for Nuclear Thermal Propulsion, other terrestrial applications can be thought of as well, making the system highly suited for a common space-terrestrial application research and utilisation strategy. (authors)

Frischauf, Norbert [QASAR Technologie(s) GmbH, Johann Gottekgasse 39, A-1230, Vienna (Austria); Hettmer, Manfred; Grassauer, Andreas; Bartusch, Tobias [QASAR Technologie(s) GmbH, Johann Gottekgasse 39, A-1230, Vienna (Austria); Koudelka, Otto [Institute of Communication Networks and Satellite Communication, Graz University of Technology, Inffeldgasse 12/I, A-8010 Graz (Austria)

2006-07-01T23:59:59.000Z

243

Minimally Invasive Magnetic Resonance Imaging-Guided Free-Hand Aspiration of Symptomatic Nerve Route Compressing Lumbosacral Cysts Using a 1.0-Tesla Open Magnetic Resonance Imaging System  

SciTech Connect

Purpose: To evaluate the feasibility of minimally invasive magnetic resonance imaging (MRI)-guided free-hand aspiration of symptomatic nerve route compressing lumbosacral cysts in a 1.0-Tesla (T) open MRI system using a tailored interactive sequence. Materials and Methods: Eleven patients with MRI-evident symptomatic cysts in the lumbosacral region and possible nerve route compressing character were referred to a 1.0-T open MRI system. For MRI interventional cyst aspiration, an interactive sequence was used, allowing for near real-time position validation of the needle in any desired three-dimensional plane. Results: Seven of 11 cysts in the lumbosacral region were successfully aspirated (average 10.1 mm [SD {+-} 1.9]). After successful cyst aspiration, each patient reported speedy relief of initial symptoms. Average cyst size was 9.6 mm ({+-}2.6 mm). Four cysts (8.8 {+-} 3.8 mm) could not be aspirated. Conclusion: Open MRI systems with tailored interactive sequences have great potential for cyst aspiration in the lumbosacral region. The authors perceive major advantages of the MR-guided cyst aspiration in its minimally invasive character compared to direct and open surgical options along with consecutive less trauma, less stress, and also less side-effects for the patient.

Bucourt, Maximilian de, E-mail: mdb@charite.de; Streitparth, Florian, E-mail: florian.streitparth@charite.de; Collettini, Federico [Charite-University Medicine, Department of Radiology (Germany); Guettler, Felix [Jena University, Department of Radiology (Germany); Rathke, Hendrik; Lorenz, Britta; Rump, Jens; Hamm, Bernd [Charite-University Medicine, Department of Radiology (Germany); Teichgraeber, U. K. [Jena University, Department of Radiology (Germany)

2012-02-15T23:59:59.000Z

244

Magnetic resonance as a structural probe of a uranium (VI) sol-gel process  

DOE Green Energy (OSTI)

NMR investigations on the ORNL process for sol-gel synthesis of microspherical nuclear fuel (UO{sub 2}), has been useful in sorting out the chemical mechanism in the sol-gel steps. {sup 13}C, {sup 15}N, and {sup 1}H NMR studies on the HMTA gelation agent (Hexamethylene tetramine, C{sub 6}H{sub l2}N{sub 4}) has revealed near quantitative stability of this adamantane-like compound in the sol-Gel process, contrary to its historical role as an ammonia source for gelation from the worldwide technical literature. {sub 17}0 NMR of uranyl (UO{sub 2}{sup ++}) hydrolysis fragments produced in colloidal sols has revealed the selective formation of a uranyl trimer, ((UO{sub 2}){sub 3}({mu}{sub 3}-O)({mu}{sub 2}-OH){sub 3}){sup +}, induced by basic hydrolysis with the HMTA gelation agent. Spectroscopic results show that trimer condensation occurs during sol-gel processing leading to layered polyanionic hydrous uranium oxides in which HMTAH{sup +} is occluded as an intercalation'' cation. Subsequent sol-gel processing of microspheres by ammonia washing results in in-situ ion exchange and formation of a layered hydrous ammonium uranate with a proposed structural formula of (NH{sub 4}){sub 2}((UO{sub 2}){sub 8}O{sub 4}(OH){sub 10}) {center dot} 8H{sub 2}0. This compound is the precursor to sintered U0{sub 2} ceramic fuel.

King, C.M.; Thompson, M.C.; Buchanan, B.R. (Westinghouse Savannah River Co., Aiken, SC (United States)); King, R.B. (Georgia Univ., Athens, GA (United States). Dept. of Chemistry); Garber, A.R. (South Carolina Univ., Columbia, SC (United States). Dept. of Chemistry)

1989-01-01T23:59:59.000Z

245

Magnetic resonance as a structural probe of a uranium (VI) sol-gel process  

DOE Green Energy (OSTI)

NMR investigations on the ORNL process for sol-gel synthesis of microspherical nuclear fuel (UO{sub 2}), has been useful in sorting out the chemical mechanism in the sol-gel steps. {sup 13}C, {sup 15}N, and {sup 1}H NMR studies on the HMTA gelation agent (Hexamethylene tetramine, C{sub 6}H{sub l2}N{sub 4}) has revealed near quantitative stability of this adamantane-like compound in the sol-Gel process, contrary to its historical role as an ammonia source for gelation from the worldwide technical literature. {sub 17}0 NMR of uranyl (UO{sub 2}{sup ++}) hydrolysis fragments produced in colloidal sols has revealed the selective formation of a uranyl trimer, [(UO{sub 2}){sub 3}({mu}{sub 3}-O)({mu}{sub 2}-OH){sub 3}]{sup +}, induced by basic hydrolysis with the HMTA gelation agent. Spectroscopic results show that trimer condensation occurs during sol-gel processing leading to layered polyanionic hydrous uranium oxides in which HMTAH{sup +} is occluded as an ``intercalation`` cation. Subsequent sol-gel processing of microspheres by ammonia washing results in in-situ ion exchange and formation of a layered hydrous ammonium uranate with a proposed structural formula of (NH{sub 4}){sub 2}[(UO{sub 2}){sub 8}O{sub 4}(OH){sub 10}] {center_dot} 8H{sub 2}0. This compound is the precursor to sintered U0{sub 2} ceramic fuel.

King, C.M.; Thompson, M.C.; Buchanan, B.R. [Westinghouse Savannah River Co., Aiken, SC (United States); King, R.B. [Georgia Univ., Athens, GA (United States). Dept. of Chemistry; Garber, A.R. [South Carolina Univ., Columbia, SC (United States). Dept. of Chemistry

1989-12-31T23:59:59.000Z

246

Atomic magnetic gradiometer for room temperature high sensitivity magnetic field detection  

DOE Patents (OSTI)

A laser-based atomic magnetometer (LBAM) apparatus measures magnetic fields, comprising: a plurality of polarization detector cells to detect magnetic fields; a laser source optically coupled to the polarization detector cells; and a signal detector that measures the laser source after being coupled to the polarization detector cells, which may be alkali cells. A single polarization cell may be used for nuclear magnetic resonance (NMR) by prepolarizing the nuclear spins of an analyte, encoding spectroscopic and/or spatial information, and detecting NMR signals from the analyte with a laser-based atomic magnetometer to form NMR spectra and/or magnetic resonance images (MRI). There is no need of a magnetic field or cryogenics in the detection step, as it is detected through the LBAM.

Xu,Shoujun (Berkeley, CA); Lowery, Thomas L. (Belmont, MA); Budker, Dmitry (El Cerrito, CA); Yashchuk, Valeriy V. (Richmond, CA); Wemmer, David E. (Berkeley, CA); Pines, Alexander (Berkeley, CA)

2009-08-11T23:59:59.000Z

247

A Signal-Inducing Bone Cement for Magnetic Resonance Imaging-Guided Spinal Surgery Based on Hydroxyapatite and Polymethylmethacrylate  

Science Conference Proceedings (OSTI)

The aim of this study was to develop a signal-inducing bone cement for magnetic resonance imaging (MRI)-guided cementoplasty of the spine. This MRI cement would allow precise and controlled injection of cement into pathologic lesions of the bone. We mixed conventional polymethylmethacrylate bone cement (PMMA; 5 ml methylmethacrylate and 12 g polymethylmethacrylate) with hydroxyapatite (HA) bone substitute (2-4 ml) and a gadolinium-based contrast agent (CA; 0-60 {mu}l). The contrast-to-noise ratio (CNR) of different CA doses was measured in an open 1.0-Tesla scanner for fast T1W Turbo-Spin-Echo (TSE) and T1W TSE pulse sequences to determine the highest signal. We simulated MRI-guided cementoplasty in cadaveric spines. Compressive strength of the cements was tested. The highest CNR was (1) 87.3 (SD 2.9) in fast T1W TSE for cements with 4 {mu}l CA/ml HA (4 ml) and (2) 60.8 (SD 2.4) in T1W TSE for cements with 1 {mu}l CA/ml HA (4 ml). MRI-guided cementoplasty in cadaveric spine was feasible. Compressive strength decreased with increasing amounts of HA from 46.7 MPa (2 ml HA) to 28.0 MPa (4 ml HA). An MRI-compatible cement based on PMMA, HA, and CA is feasible and clearly visible on MRI images. MRI-guided spinal cementoplasty using this cement would permit direct visualization of the cement, the pathologic process, and the anatomical surroundings.

Wichlas, Florian, E-mail: florian.wichlas@charite.de; Seebauer, Christian J.; Schilling, Rene [University Charite, Center for Musculoskeletal Surgery (Germany); Rump, Jens [University Charite, Department of Radiology (Germany); Chopra, Sascha S. [University Charite, Center for Musculoskeletal Surgery (Germany); Walter, Thula; Teichgraeber, Ulf K. M. [University Charite, Department of Radiology (Germany); Bail, Hermann J. [University Charite, Center for Musculoskeletal Surgery (Germany)

2012-06-15T23:59:59.000Z

248

Magnetic Resonance Lymphography Findings in Patients With Biochemical Recurrence After Prostatectomy and the Relation With the Stephenson Nomogram  

SciTech Connect

Purpose: To estimate the occurrence of positive lymph nodes on magnetic resonance lymphography (MRL) in patients with a prostate-specific antigen (PSA) recurrence after prostatectomy and to investigate the relation between score on the Stephenson nomogram and lymph node involvement on MRL. Methods and Materials: Sixty-five candidates for salvage radiation therapy were referred for an MRL to determine their lymph node status. Clinical and histopathologic features were recorded. For 49 patients, data were complete to calculate the Stephenson nomogram score. Receiver operating characteristic (ROC) analysis was performed to determine how well this nomogram related to the MRL result. Analysis was done for the whole group and separately for patients with a PSA <1.0 ng/mL to determine the situation in candidates for early salvage radiation therapy, and for patients without pathologic lymph nodes at initial lymph node dissection. Results: MRL detected positive lymph nodes in 47 patients. ROC analysis for the Stephenson nomogram yielded an area under the curve (AUC) of 0.78 (95% confidence interval, 0.61-0.93). Of 29 patients with a PSA <1.0 ng/mL, 18 had a positive MRL. Of 37 patients without lymph node involvement at initial lymph node dissection, 25 had a positive MRL. ROC analysis for the Stephenson nomogram showed AUCs of 0.84 and 0.74, respectively, for these latter groups. Conclusion: MRL detected positive lymph nodes in 72% of candidates for salvage radiation therapy, in 62% of candidates for early salvage radiation therapy, and in 68% of initially node-negative patients. The Stephenson nomogram showed a good correlation with the MRL result and may thus be useful for identifying patients with a PSA recurrence who are at high risk for lymph node involvement.

Meijer, Hanneke J.M., E-mail: H.Meijer@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Debats, Oscar A. [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)] [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Roach, Mack [Department of Radiation Oncology and Urology, University of California San Francisco, San Francisco, California (United States)] [Department of Radiation Oncology and Urology, University of California San Francisco, San Francisco, California (United States); Span, Paul N. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)] [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Witjes, J. Alfred [Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)] [Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Kaanders, Johannes H.A.M.; Lin, Emile N.J.Th. van [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Barentsz, Jelle O. [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)] [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

2012-12-01T23:59:59.000Z

249

Neutrino oscillations in nuclear media  

E-Print Network (OSTI)

On basis of effective interactions of charged lepton and hadron currents, we obtain an effective interacting Hamiltonian of neutrinos in nuclear media up to the leading order. Using this effective Hamiltonian, we study neutrino mixing and oscillations in nuclear media and strong magnetic fields. We compute neutrino mixing angle and mass squared difference, and find the pattern of vacuum neutrino oscillations is modified in magnetized nuclear media. Comparing with the vacuum neutrino oscillation, we find that for high-energy neutrinos, neutrino oscillations are suppressed in the presence of nuclear media. In the general case of neutral nuclear media with the presence of electrons, we calculate the mixing angle and mass squared difference, and discuss the resonance and level-crossing in neutrino oscillations.

Iman Motie; She-Sheng Xue

2011-04-14T23:59:59.000Z

250

Lensless Imaging of Magnetic Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine....

251

Development of Self-Interrogation Neutron Resonance Densitometry (SINRD) to Measure the Fissile Content in Nuclear Fuel  

E-Print Network (OSTI)

The development of non-destructive assay (NDA) capabilities to directly measure the fissile content in spent fuel is needed to improve the timely detection of the diversion of significant quantities of fissile material. Currently, the International Atomic Energy Agency (IAEA) does not have effective NDA methods to verify spent fuel and recover continuity of knowledge in the event of a containment and surveillance systems failure. This issue has become increasingly critical with the worldwide expansion of nuclear power, adoption of enhanced safeguards criteria for spent fuel verification, and recent efforts by the IAEA to incorporate an integrated safeguards regime. In order to address these issues, the use of Self-Interrogation Neutron Resonance Densitometry (SINRD) has been developed to improve existing nuclear safeguards and material accountability measurements. The following characteristics of SINRD were analyzed: (1) ability to measure the fissile content in Light Water Reactors (LWR) fuel assemblies and (2) sensitivity and penetrability of SINRD to the removal of fuel pins from an assembly. The Monte Carlo Neutral Particle eXtended (MCNPX) transport code was used to simulate SINRD for different geometries. Experimental measurements were also performed with SINRD and were compared to MCNPX simulations of the experiment to verify the accuracy of the MCNPX model of SINRD. Based on the results from these simulations and measurements, we have concluded that SINRD provides a number of improvements over current IAEA verification methods. These improvements include: 1) SINRD provides absolute measurements of burnup independent of the operators declaration. 2) SINRD is sensitive to pin removal over the entire burnup range and can verify the diversion of 6% of fuel pins within 3? from LWR spent LEU and MOX fuel. 3) SINRD is insensitive to the boron concentration and initial fuel enrichment and can therefore be used at multiple spent fuel storage facilities. 4) The calibration of SINRD at one reactor facility carries over to reactor sites in different countries because it uses the ratio of fission chambers (FCs) that are not facility dependent. 5) SINRD can distinguish fresh and 1-cycle spent MOX fuel from 3- and 4-cycles spent LEU fuel without using reactor burnup codes.

Lafleur, Adrienne

2011-08-01T23:59:59.000Z

252

Journal of Magnetic Resonance  

Flow Microcoil Remote detection ... 2 Inlet valve Inlet pressure Outlet valve Outlet pressure ... 2. The price of storing the phase in this manner is that each data

253

Organic Light-Emitting Diodes (OLEDs) and Optically-Detected Magnetic Resonance (ODMR) studies on organic materials  

Science Conference Proceedings (OSTI)

Organic semiconductors have evolved rapidly over the last decades and currently are considered as the next-generation technology for many applications, such as organic light-emitting diodes (OLEDs) in flat-panel displays (FPDs) and solid state lighting (SSL), and organic solar cells (OSCs) in clean renewable energy. This dissertation focuses mainly on OLEDs. Although the commercialization of the OLED technology in FPDs is growing and appears to be just around the corner for SSL, there are still several key issues that need to be addressed: (1) the cost of OLEDs is very high, largely due to the costly current manufacturing process; (2) the efficiency of OLEDs needs to be improved. This is vital to the success of OLEDs in the FPD and SSL industries; (3) the lifetime of OLEDs, especially blue OLEDs, is the biggest technical challenge. All these issues raise the demand for new organic materials, new device structures, and continued lower-cost fabrication methods. In an attempt to address these issues, we used solution-processing methods to fabricate highly efficient small molecule OLEDs (SMOLEDs); this approach is costeffective in comparison to the more common thermal vacuum evaporation. We also successfully made efficient indium tin oxide (ITO)-free SMOLEDs to further improve the efficiency of the OLEDs. We employed the spin-dependent optically-detected magnetic resonance (ODMR) technique to study the luminescence quenching processes in OLEDs and organic materials in order to understand the intrinsic degradation mechanisms. We also fabricated polymer LEDs (PLEDs) based on a new electron-accepting blue-emitting polymer and studied the effect of molecular weight on the efficiency of PLEDs. All these studies helped us to better understand the underlying relationship between the organic semiconductor materials and the OLEDs performance, and will subsequently assist in further enhancing the efficiency of OLEDs. With strongly improved device performance (in addition to other OLEDs' attributes such as mechanical flexibility and potential low cost), the OLED technology is promising to successfully compete with current technologies, such as LCDs and inorganic LEDs.

Cai, Min

2011-11-30T23:59:59.000Z

254

Quantum read-out and fast initialization of nuclear spin qubits with electric currents  

E-Print Network (OSTI)

Nuclear spin qubits have the longest coherence times in the solid state, but their quantum read-out and initialization is a great challenge. We present a theory for the interaction of an electric current with the nuclear spins of donor impurities in semiconductors. The theory yields a sensitivity criterion for quantum detection of nuclear spin states using electrically detected magnetic resonance, as well as an all electrical method for fast nuclear spin qubit initialization.

Noah Stemeroff; Rogerio de Sousa

2011-08-02T23:59:59.000Z

255

Investigations of the R5(SixGe1-x)4 Intermetallic Compounds by X-Ray Resonant Magnetic Scattering  

SciTech Connect

The XRMS experiment on the Gd{sub 5}Ge{sub 4} system has shown that, below the Neel temperature, T{sub N} = 127 K, the magnetic unit cells is the same as the chemical unit cell. From azimuth scans and the Q dependence of the magnetic scattering, all three Gd sites in the structure were determined to be in the same magnetic space group Pnma. The magnetic moments are aligned along the c-axis and the c-components of the magnetic moments at the three different sites are equal. The ferromagnetic slabs are stacked antiferromagnetically along the b-direction. They found an unusual order parameter curve in Gd{sub 5}Ge{sub 4}. A spin-reorientation transition is a possibility in Gd{sub 5}Ge{sub 4}, which is similar to the Tb{sub 5}Ge{sub 4} case. Tb{sub 5}Ge{sub 4} possesses the same Sm{sub 5}Ge{sub 4}-type crystallographic structure and the same magnetic space group as Gd{sub 5}Ge{sub 4} does. The difference in magnetic structure is that Tb{sub 5}Ge{sub 4} has a canted one but Gd{sub 5}Ge{sub 4} has nearly a collinear one in the low temperature antiferromagnetic phase. The competition between the magneto-crystalline anisotropy and the nearest-neighbor magnetic exchange interactions may allow a 3-dimensional canted antiferromagnetic structure in Tb{sub 5}Ge{sub 4}. The spin-reorientation transition in both Gd{sub 5}Ge{sub 4} and Tb{sub 5}Ge{sub 4} may arise from the competition between the magnetic anisotropy from the spin-orbit coupling of the conduction electrons and the dipolar interactions anisotropy.

Lizhi Tan

2008-08-18T23:59:59.000Z

256

Study of the influence of a strong magnetic field on the composition of nuclear matter at high densities and zero temperature  

Science Conference Proceedings (OSTI)

Magnetars are neutron stars with a strong surface magnetic field. Observations of soft gamma-ray and anomalous X-ray pulsars pointed out that the surface magnetic field of magnetars is equal or even greater than 10{sup 15} G. In this work we study the influence of a strong magnetic field on the composition of nuclear matter at high densities and zero temperature. We describe the matter through a relativistic mean-field model with eight light baryons (baryon octet), electrons, muons and with magnetic field. As output of the numerical calculations, we obtain the relative population of each species of particles as function of baryon density.

Coelho, Eduardo L.; Chiapparini, Marcelo [Instituto de Fisica, Universidade do Estado do Rio de Janeiro, 20559-900, Rio de Janeiro, RJ (Brazil); Bracco, Mirian E. [Faculdade de Tecnologia, Universidade do Estado do Rio de Janeiro, 27537-000, Resende, RJ (Brazil)

2013-03-25T23:59:59.000Z

257

Phase II Trial of Radiosurgery to Magnetic Resonance Spectroscopy-Defined High-Risk Tumor Volumes in Patients With Glioblastoma Multiforme  

SciTech Connect

Purpose: To determine the efficacy of a Gamma Knife stereotactic radiosurgery (SRS) boost to areas of high risk determined by magnetic resonance spectroscopy (MRS) functional imaging in addition to standard radiotherapy for patients with glioblastoma (GBM). Methods and Materials: Thirty-five patients in this prospective Phase II trial underwent surgical resection or biopsy for a GBM followed by SRS directed toward areas of MRS-determined high biological activity within 2 cm of the postoperative enhancing surgical bed. The MRS regions were determined by identifying those voxels within the postoperative T2 magnetic resonance imaging volume that contained an elevated choline/N-acetylaspartate ratio in excess of 2:1. These voxels were marked, digitally fused with the SRS planning magnetic resonance image, targeted with an 8-mm isocenter per voxel, and treated using Radiation Therapy Oncology Group SRS dose guidelines. All patients then received conformal radiotherapy to a total dose of 60 Gy in 2-Gy daily fractions. The primary endpoint was overall survival. Results: The median survival for the entire cohort was 15.8 months. With 75% of recursive partitioning analysis (RPA) Class 3 patients still alive 18 months after treatment, the median survival for RPA Class 3 has not yet been reached. The median survivals for RPA Class 4, 5, and 6 patients were 18.7, 12.5, and 3.9 months, respectively, compared with Radiation Therapy Oncology Group radiotherapy-alone historical control survivals of 11.1, 8.9, and 4.6 months. For the 16 of 35 patients who received concurrent temozolomide in addition to protocol radiotherapeutic treatment, the median survival was 20.8 months, compared with European Organization for Research and Treatment of Cancer historical controls of 14.6 months using radiotherapy and temozolomide. Grade 3/4 toxicities possibly attributable to treatment were 11%. Conclusions: This represents the first prospective trial using selective MRS-targeted functional SRS combined with radiotherapy for patients with GBM. This treatment is feasible, with acceptable toxicity and patient survivals higher than in historical controls. This study can form the basis for a multicenter, randomized trial.

Einstein, Douglas B., E-mail: douglas.einstein@khnetwork.org [Department of Radiation Oncology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Wessels, Barry [Department of Radiation Oncology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Radiation Oncology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Bangert, Barbara [Department of Radiology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Radiology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Fu, Pingfu [Department of Biostatistics, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Biostatistics, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Nelson, A. Dennis [Department of Radiology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Radiology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Cohen, Mark [Department of Pathology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Pathology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Sagar, Stephen [Department of Neurology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Neurology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Lewin, Jonathan [Department of Radiology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Radiology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Sloan, Andrew [Department of Neurosurgery, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Neurosurgery, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Zheng Yiran; Williams, Jordonna; Colussi, Valdir; Vinkler, Robert [Department of Radiation Oncology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Radiation Oncology, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States); Maciunas, Robert [Department of Neurosurgery, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)] [Department of Neurosurgery, Case Comprehensive Cancer Center, Case Western Reserve University Kettering, Ohio (United States)

2012-11-01T23:59:59.000Z

258

Sequence optimization to reduce velocity offsets in cardiovascular magnetic resonance volume flow quantification - A multi-vendor study  

E-Print Network (OSTI)

of interest may lead to phase-encode wraparound hinder- ing conventional background correction post-processing if still needed. Sequence development might also focus on a more fundamental level of eddy current compensation, such as sequence... and Correcting Gradient Errors in Non-Cartesian Imaging: Are Gradient Errors Linear Time-Invariant (LTI)? Magn Reson Med 2009, 62:1466-1476. 16. Bernstein MA, King KF, Zhou XHJ: Correction Gradients - Eddy Current Compensation. Handbook of MRI pulse sequences...

Rolf, Marijn P; Hofman, Mark B M; Gatehouse, Peter D; Markenroth Bloch, Karin; Heymans, Martijn W; Ebbers, Tino; Graves, Martin J; Totman, John J; Werner, Beat; Rossum, Albert C van; Kilner, Philip J; Heethaar, Rob M

2011-03-09T23:59:59.000Z

259

New Modes of Nuclear Excitations  

E-Print Network (OSTI)

We present a theoretical approach based on density functional theory supplemented by a microscopic multi-phonon model which is applied for investigations of pygmy resonances and other excitations of different multipolarities in stable and exotic nuclei. The possible relation of low-energy modes to the properties of neutron or proton skins is systematically studied in isotonic and isotopic chains. The fine structure of nuclear electric and magnetic response functions is analyzed and compared to experimental data. Their relevance to nuclear astrophysics is discussed.

Nadia Tsoneva; Horst Lenske

2013-09-30T23:59:59.000Z

260

Design and characterization of 2.45 GHz electron cyclotron resonance plasma source with magnetron magnetic field configuration for high flux of hyperthermal neutral beam  

Science Conference Proceedings (OSTI)

A 2.45 GHz electron cyclotron resonance (ECR) source with a magnetron magnetic field configuration was developed to meet the demand of a hyperthermal neutral beam (HNB) flux on a substrate of more than 1x10{sup 15} cm{sup -2} s{sup -1} for industrial applications. The parameters of the operating pressure, ion density, electron temperature, and distance between the neutralization plate and the substrate for the HNB source are specified in a theoretical analysis. The electron temperature and the ion density are measured to characterize the ECR HNB source using a Langmuir probe and optical emission spectroscopy. The parameters of the ECR HNB source are in good agreement with the theoretically specified parameters.

Kim, Seong Bong [Department of Physics, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Convergence Plasma Research Center, National Fusion Research Institute, Gwahangno 113, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Kim, Dae Chul; Yoo, Suk Jae [Convergence Plasma Research Center, National Fusion Research Institute, Gwahangno 113, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Namkung, Won; Cho, Moohyun [Department of Physics, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of)

2010-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
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261

Application of the pulsed magnetic welding process to nuclear breeder reactor fuel pin end closures  

SciTech Connect

The pulsed magnetic welding process is a solid state welding process in which metallurgical bonding is effected by impacting metal or alloy parts against each other at high velocity by use of controlled high frequency, high intensity pulsed magnetic fields. This process is similar to the explosive welding process except that magnetic energy is used for impacting the parts together instead of using explosive energy. The pulsed magnetic welding (PMW) process is readily applied to the welding of cylindrical plugs to small diameter tubes. Although breeder reactor fuel pin design may vary in size, the application described here consisted of cladding tubes approximately 6.4 mm in diameter by 244 cm long with a wall thickness of 0.38 mm. After the cladding tubes are filled with fuel pellets and associated metal hardware, tapered end plugs are inserted into the end of the tubes and welded. A typical setup for PMW is described.

Brown, W.F.

1984-01-01T23:59:59.000Z

262

Free-Electron Laser-Powered Electron Paramagnetic Resonance Spectroscopy  

E-Print Network (OSTI)

Electron paramagnetic resonance (EPR) spectroscopy interrogates unpaired electron spins in solids and liquids to reveal local structure and dynamics; for example, EPR has elucidated parts of the structure of protein complexes that have resisted all other techniques in structural biology. EPR can also probe the interplay of light and electricity in organic solar cells and light-emitting diodes, and the origin of decoherence in condensed matter, which is of fundamental importance to the development of quantum information processors. Like nuclear magnetic resonance (NMR), EPR spectroscopy becomes more powerful at high magnetic fields and frequencies, and with excitation by coherent pulses rather than continuous waves. However, the difficulty of generating sequences of powerful pulses at frequencies above 100 GHz has, until now, confined high-power pulsed EPR to magnetic fields of 3.5 T and below. Here we demonstrate that ~1 kW pulses from a free-electron laser (FEL) can power a pulsed EPR spectrometer at 240 GHz...

Takahashi, S; Edwards, D T; van Tol, J; Ramian, G; Han, S; Sherwin, M S

2012-01-01T23:59:59.000Z

263

Repetitive resonant railgun power supply  

DOE Patents (OSTI)

A repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. The supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles.

Honig, Emanuel M. (Los Alamos, NM); Nunnally, William C. (Los Alamos, NM)

1988-01-01T23:59:59.000Z

264

Repetitive resonant railgun power supply  

DOE Patents (OSTI)

A repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. The supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles.

Honig, E.M.; Nunnally, W.C.

1985-06-19T23:59:59.000Z

265

NUCLEAR SCIENCE ANNUAL REPORT 1977-1978  

E-Print Network (OSTI)

A Relation Between Nuclear Dynamics and the RenormalizationMultiplicity Distributions in Nuclear Collision M. GyulassyHigh Energy Nuclear Collisions in the Resonance Dominated

Schroeder, L.S.

2011-01-01T23:59:59.000Z

266

Direct Characterization of Kerogen by X-ray and Solid-State [superscript 13]C Nuclear Magnetic Resonance Methods  

Science Conference Proceedings (OSTI)

A combination of solid-state {sup 13}C NMR, X-ray photoelectron spectroscopy (XPS) and sulfur X-ray absorption near edge structure (S-XANES) techniques are used to characterize organic oxygen, nitrogen, and sulfur species and carbon chemical/structural features in kerogens. The kerogens studied represent a wide range of organic matter types and maturities. A van Krevelen plot based on elemental H/C data and XPS derived O/C data shows the well established pattern for type I, type II, and type III kerogens. The anticipated relationship between the Rock-Eval hydrogen index and H/C is independent of organic matter type. Carbon structural and lattice parameters are derived from solid-state {sup 13}C NMR analysis. As expected, the amount of aromatic carbon, measured by both {sup 13}C NMR and XPS, increases with decreasing H/C. The correlation between aromatic carbon and Rock-Eval T{sub max}, an indicator of maturity, is linear for types II and IIIC kerogens, but each organic matter type follows a different relationship. The average aliphatic carbon chain length (Cn) decreases with an increasing amount of aromatic carbon in a similar manner across all organic matter types. The fraction of aromatic carbons with attachments (FAA) decreases, while the average number of aromatic carbons per cluster (C) increases with an increasing amount of aromatic carbon. FAA values range from 0.2 to 0.4, and C values range from 12 to 20 indicating that kerogens possess on average 2- to 5-ring aromatic carbon units that are highly substituted. There is basic agreement between XPS and {sup 13}C NMR results for the amount and speciation of organic oxygen. XPS results show that the amount of carbon oxygen single bonded species increases and carbonyl-carboxyl species decrease with an increasing amount of aromatic carbon. Patterns for the relative abundances of nitrogen and sulfur species exist regardless of the large differences in the total amount of organic nitrogen and sulfur seen in the kerogens. XPS and S-XANES results indicate that the relative level of aromatic sulfur increases with an increasing amount of aromatic carbon for all kerogens. XPS show that the majority of nitrogen exists as pyrrolic forms in comparable relative abundances in all kerogens studied. The direct characterization results using X-ray and NMR methods for nitrogen, sulfur, oxygen, and carbon chemical structures provide a basis for developing both specific and general average chemical structural models for different organic matter type kerogens.

Kelemen, S. R.; Afeworki, M.; Gorbaty, M.L.; Sansone, M.; Kwiatek, P.J.; Walters, C.C.; Freund, H.; Siskin, M.; Bence, A.E.; Curry, D.J.; Solum, M.; Pugmire, R.J.; Vandenbroucke, M.; Leblond, M.; Behar, F. (ExxonMobil); (ExxonMobil); (IFP); (Utah)

2008-06-12T23:59:59.000Z

267

Nuclear magnetic resonance studies of domain growth in the late stage of phase separation of a binary liquid mixture  

Science Conference Proceedings (OSTI)

The domain growth processes occurring during the gravity?dominated regime of the phase separation of a cyclohexane/aniline critical mixture

Franco Cau; Serge Lacelle

1995-01-01T23:59:59.000Z

268

Proton nuclear magnetic resonance studies of hydrogen diffusion and electron tunneling in Ni-Nb-Zr-H glassy alloys  

Science Conference Proceedings (OSTI)

Using the Fourier transform of the echo envelope, the proton line shapes, spin-lattice relaxation time, and spin-spin relaxation time have been measured in a (Ni{sub 0.36}Nb{sub 0.24}Zr{sub 0.40}){sub 90}H{sub 10} glassy alloy at 1.83 T ({approx}78 MHz) and at temperatures between 1.8 and 300 K. First, the spectral line width decreases abruptly between 1.8 and 2.1 K. Next, it remains almost constant at 13 kHz up to {approx}150 K. Finally, the line width decreases as the temperature increases from {approx}150 to 300 K. The initial decrease in the spectral line width is ascribed to the distribution of the external field, which is caused by the penetration of vortices in the superconducting state. The subsequent leveling off in the spectral line width is ascribed to the dipole-dipole interaction between protons when hydrogen atoms are trapped into vacancies among the Zr-centered icosahedral Zr{sub 5}Ni{sub 5}Nb{sub 3} clusters. The final decrease in the spectral line width is ascribed to the motional narrowing of the width that is caused by the movement of hydrogen atoms. The temperature dependences of the spin-lattice and spin-spin relaxation time showed that at temperature above 150 K and the activation energy of 8.7 kJ/mol allowed the hydrogen atoms to migrate among the clusters. The distance between the hydrogen atoms is estimated to be 2.75 A. Hydrogen occupancies among clusters in the (Ni{sub 0.36}Nb{sub 0.24}Zr{sub 0.40}){sub 90}H{sub 10} glassy alloy play an important role in the diffusion behavior and in the electronic properties of this alloy.

Niki, Haruo; Okuda, Hiroyuki; Oshiro, Morihito; Yogi, Mamoru [Department of Physics, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa 903-0213 (Japan); Seki, Ichiro; Fukuhara, Mikio [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

2012-06-15T23:59:59.000Z

269

Direct Characterization of Kerogen By X-Ray And Solid-State **13C Nuclear Magnetic Resonance Methods  

DOE Green Energy (OSTI)

A combination of solid-state {sup 13}C NMR, X-ray photoelectron spectroscopy (XPS) and sulfur X-ray absorption near edge structure (S-XANES) techniques are used to characterize organic oxygen, nitrogen, and sulfur species and carbon chemical/structural features in kerogens. The kerogens studied represent a wide range of organic matter types and maturities. A van Krevelen plot based on elemental H/C data and XPS derived O/C data shows the well established pattern for type I, type II, and type III kerogens. The anticipated relationship between the Rock-Eval hydrogen index and H/C is independent of organic matter type. Carbon structural and lattice parameters are derived from solid-state 13C NMR analysis. As expected, the amount of aromatic carbon, measured by both {sup 13}C NMR and XPS, increases with decreasing H/C. The correlation between aromatic carbon and Rock-Eval Tmax, an indicator of maturity, is linear for types II and IIIC kerogens, but each organic matter type follows a different relationship. The average aliphatic carbon chain length (Cn') decreases with an increasing amount of aromatic carbon in a similar manner across all organic matter types. The fraction of aromatic carbons with attachments (FAA) decreases, while the average number of aromatic carbons per cluster (C) increases with an increasing amount of aromatic carbon. FAA values range from 0.2 to 0.4, and C values range from 12 to 20 indicating that kerogens possess on average 2- to 5-ring aromatic carbon units that are highly substituted. There is basic agreement between XPS and 13C NMR results for the amount and speciation of organic oxygen. XPS results show that the amount of carbon oxygen single bonded species increases and carbonyl-carboxyl species decrease with an increasing amount of aromatic carbon. Patterns for the relative abundances of nitrogen and sulfur species exist regardless of the large differences in the total amount of organic nitrogen and sulfur seen in the kerogens. XPS and S-XANES results indicate that the relative level of aromatic sulfur increases with an increasing amount of aromatic carbon for all kerogens. XPS show that the majority of nitrogen exists as pyrrolic forms in comparable relative abundances in all kerogens studied. The direct characterization results using X-ray and NMR methods for nitrogen, sulfur, oxygen, and carbon chemical structures provide a basis for developing both specific and general average chemical structural models for different organic matter type kerogens.

Keleman, S.R.; Afeworki, M.; Gorbaty, M.L.; Sansone, M.; Kwiatek, P.J.; Walters, C.C.; Freund, H.; Siskin, M.; Bence, A.E.; Curry, D.J.; Solum, M.; Pugmire, R.J.; Vandenbroucke, M.; Leblond, M.; Behar, F.

2007-07-09T23:59:59.000Z

270

Magnetic Devices and Nanostructures (2005)  

Science Conference Proceedings (OSTI)

... Molecular nanomagnets, which are the smallest well defined magnetic ... moment of a specimen as microwave stimulation causes resonance at ...

2010-10-13T23:59:59.000Z

271

Metabonomics for detection of nuclear materials processing.  

SciTech Connect

Tracking nuclear materials production and processing, particularly covert operations, is a key national security concern, given that nuclear materials processing can be a signature of nuclear weapons activities by US adversaries. Covert trafficking can also result in homeland security threats, most notably allowing terrorists to assemble devices such as dirty bombs. Existing methods depend on isotope analysis and do not necessarily detect chronic low-level exposure. In this project, indigenous organisms such as plants, small mammals, and bacteria are utilized as living sensors for the presence of chemicals used in nuclear materials processing. Such 'metabolic fingerprinting' (or 'metabonomics') employs nuclear magnetic resonance (NMR) spectroscopy to assess alterations in organismal metabolism provoked by the environmental presence of nuclear materials processing, for example the tributyl phosphate employed in the processing of spent reactor fuel rods to extract and purify uranium and plutonium for weaponization.

Alam, Todd Michael; Luxon, Bruce A. (University Texas Medical Branch); Neerathilingam, Muniasamy (University Texas Medical Branch); Ansari, S. (University Texas Medical Branch); Volk, David (University Texas Medical Branch); Sarkar, S. (University Texas Medical Branch); Alam, Mary Kathleen

2010-08-01T23:59:59.000Z

272

Reactor-relevant quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields  

Science Conference Proceedings (OSTI)

Results from recent experiments demonstrate that quiescent H-mode (QH-mode) sustained by magnetic torque from non-axisymmetric magnetic fields is a promising operating mode for future burning plasmas. Using magnetic torque from n=3 fields to replace counter-I{sub p} torque from neutral beam injection (NBI), we have achieved long duration, counter-rotating QH-mode operation with NBI torque ranging from counter-I{sub p} to up to co-I{sub p} values of 1-1.3 Nm. This co-I{sub p} torque is 3 to 4 times the scaled torque that ITER will have. These experiments utilized an ITER-relevant lower single-null plasma shape and were done with ITER-relevant values of {nu}{sub ped}{sup *} and {beta}{sub N}{sup ped}. These discharges exhibited confinement quality H{sub 98y2}=1.3, in the range required for ITER. In preliminary experiments using n=3 fields only from a coil outside the toroidal coil, QH-mode plasmas with low q{sub 95}=3.4 have reached fusion gain values of G={beta}{sub N}H{sub 89}/q{sub 95}{sup 2}=0.4, which is the desired value for ITER. Shots with the same coil configuration also operated with net zero NBI torque. The limits on G and co-I{sub p} torque have not yet been established for this coil configuration. QH-mode work to has made significant contact with theory. The importance of edge rotational shear is consistent with peeling-ballooning mode theory. Qualitative and quantitative agreements with the predicted neoclassical toroidal viscosity torque is seen.

Burrell, K. H.; Garofalo, A. M; Osborne, T. H.; Schaffer, M. J.; Snyder, P. B. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Solomon, W. M.; Park, J.-K. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Fenstermacher, M. E. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2012-05-15T23:59:59.000Z

273

A novel contrast agent with rare earth-doped up-conversion luminescence and Gd-DTPA magnetic resonance properties  

SciTech Connect

The magnetic-luminescent multifunctional nanoparticles based on Gd-DTPA and NaYF{sub 4}:Yb, Er were successfully synthesized by the conjugation of activated DTPA and silica-coated/surface-aminolated NaYF{sub 4}:Yb, Er nanoparticles through EDC/NHS coupling chemistry. The as-prepared products were characterized by powder X-ray diffraction, transmission electron microscopy, dynamic light scattering, energy dispersive X-ray analysis, and fourier transform infrared spectrometry. The room-temperature upconversion luminescent spectra and T{sub 1}-weighted maps of the obtained nanoparticles were carried out by 980 nm NIR light excitation and a 3T MR imaging scanner, respectively. The results indicated that the as-synthesized multifunctional nanoparticles with small size, highly solubility in water, and both high MR relaxivities and upconversion luminescence may have potential usage for MR imaging in future. - Graphical abstract: We have synthesized magnetic-luminescent multifunctional nanoparticles based on Gd-DTPA and NaYF4:Yb, Er by the conjugation of activated DTPA and silica-coated/surface-aminolated NaYF4:Yb, Er nanoparticles through EDC/NHS coupling chemistry. Highlights: Black-Right-Pointing-Pointer A novel magnetic-luminescent multifunctional nanoparticles are synthesized. Black-Right-Pointing-Pointer The nanoparticles are highly efficient for luminescence and T{sub 1}-weighted MR imaging. Black-Right-Pointing-Pointer The nanoparticles are small in size and highly solubility in water. Black-Right-Pointing-Pointer The nanoparticles hold great potential usage for future biomedical engineering.

Lu Qing [Department of Radiology, Shanghai Renji Hospital, Shanghai Jiao Tong University School of Medicine, 1630 Dong Fang Rd, Shanghai 200127 (China); Wei Daixu [National Engineering Research Center for Nanotechnology, 28 East Jiang Chuan Rd, Shanghai 200241 (China); Cheng Jiejun [Department of Radiology, Shanghai Renji Hospital, Shanghai Jiao Tong University School of Medicine, 1630 Dong Fang Rd, Shanghai 200127 (China); Xu Jianrong, E-mail: xujianr@hotmail.com [Department of Radiology, Shanghai Renji Hospital, Shanghai Jiao Tong University School of Medicine, 1630 Dong Fang Rd, Shanghai 200127 (China); Zhu Jun, E-mail: yzjzhu@163.com [National Engineering Research Center for Nanotechnology, 28 East Jiang Chuan Rd, Shanghai 200241 (China)

2012-08-15T23:59:59.000Z

274

magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

I I Painless Physics Articles BEAM COOLING August 2, 1996 By Leila Belkora, Office of Public Affairs ACCELERATION August 16, 1996 By Dave Finley, Accelerator Division Head RF August 30, 1996 By Pat Colestock, Accelerator Division FIXED TARGET PHYSICS September 20, 1996 By Peter H. Garbincius, Physics Section FIXED TARGET PHYSICS PART DEUX October 16, 1996 By Peter H. Garbincius, Physics Section and Leila Belkora, Office of Public Affaris CROSS SECTION November 1, 1996 By Doreen Wackeroth, Theoretical Physics Edited by Leila Belkora, Office of Public Affaris MAGNETS PART I November 15, 1996 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs MAGNETS PART II January 10, 1997 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs

275

Novel motor design for rotating anode x-ray tubes operating in the fringe field of a magnetic resonance imaging system  

SciTech Connect

Purpose: Using hybrid x-ray/MR (XMR) systems for image guidance during interventional procedures could enhance the diagnosis and treatment of neurologic, oncologic, cardiovascular, and other disorders. The authors propose a close proximity hybrid system design in which a C-arm fluoroscopy unit is placed immediately adjacent to the solenoid magnet of a MR system with a minimum distance of 1.2 m between the x-ray and MR imaging fields of view. Existing rotating anode x-ray tube designs fail within MR fringe field environments because the magnetic fields alter the electron trajectories in the x-ray tube and act as a brake on the induction motor, reducing the rotation speed of the anode. In this study the authors propose a novel motor design that avoids the anode rotation speed reduction. Methods: The proposed design replaces the permanent magnet stator found in brushed dc motors with the radial component of the MR fringe field. The x-ray tube is oriented such that the radial component of the MR fringe field is orthogonal to the cathode-anode axis. Using a feedback position sensor and the support bearings as electrical slip rings, the authors use electrical commutation to eliminate the need for mechanical brushes and commutators. A vacuum compatible prototype of the proposed motor design was assembled, and its performance was evaluated at various operating conditions. The prototype consisted of a 3.1 in. diameter anode rated at 300 kHU with a ceramic rotor that was 5.6 in. in length and had a 2.9 in. diameter. The material chosen for all ceramic components was MACOR, a machineable glass ceramic developed by Corning Inc. The approximate weight of the entire assembly was 1750 g. The maximum rotation speed, angular acceleration, and acceleration time of the motor design were investigated, as well as the dependence of these parameters on rotor angular offset, magnetic field strength, and field orientation. The resonance properties of the authors' assembly were also evaluated to determine its stability during acceleration, and a pulse width modulation algorithm was implemented to control the rotation speed of the motor. Results: At a magnetic flux density of 41 mT orthogonal to the axis of rotation (on the lower end of the expected flux density in the MR suite) the maximum speed of the motor was found to be 5150 revolutions per minute (rpm). The acceleration time necessary to reach 3000 rpm was found to be approximately 10 s at 59 mT. The resonance frequency of the assembly with the anode attached was 1310 rpm (21.8 Hz) which is far below the desired operating speeds. Pulse width modulation provides an effective method to control the speed of the motor with a resolution of 100 rpm. Conclusions: The proposed design can serve as a direct replacement to the conventional induction motor used in rotating anode x-ray tubes. It does not suffer from a reduced rotation speed when operating in a MR environment. The presence of chromic steel bearings in the prototype prevented testing at the higher field strengths, and future iterations of the design could eliminate this shortcoming. The prototype assembly demonstrates proof of concept of the authors' design and overcomes one of the major obstacles for a MR compatible rotating anode x-ray tube.

Lillaney, Prasheel; Pelc, Norbert [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Bioengineering, Stanford University, Stanford, California 94305 (United States); Shin Mihye [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States); Hinshaw, Waldo; Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Bennett, N. Robert [Department of Radiology, Stanford University, Stanford, California 94305 and Qualcomm MEMS Technologies, San Jose, California 95134 (United States)

2013-02-15T23:59:59.000Z

276

Chemistry-Nuclear Chemistry Division. Progress report, October 1980-September 1981  

Science Conference Proceedings (OSTI)

This report describes major progress in the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory during FY 1981. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, medical radioisotopes research, element migration and fixation, nuclear waste isolation research, inorganic and structural chemistry, isotope separation, analysis and applications, the newly established Nuclear Magnetic Resonance Center, atomic and molecular collisions, molecular spectroscopy, nuclear cosmochemistry, nuclear structure and reactions, pion charge exchange, radiochemical separations, theoretical chemistry, and unclassified weapons research.

Ryan, R.R. (comp.)

1982-05-01T23:59:59.000Z

277

Search for Chiral Magnetic Effects in High-Energy Nuclear Collisions  

E-Print Network (OSTI)

We present measurements of pion elliptic flow ($v_2$) in Au+Au collisions at $\\sNN =$ 200, 62.4, 39, 27 and 19.6 GeV, as a function of event-by-event charge asymmetry ($A_{\\pm}$), based on data from the STAR experiment at RHIC. We find that $\\pi^-$ ($\\pi^+$) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins and for all the beam energies under study. The slope parameter ($r$) from $v_2(A_\\pm)$ difference between $\\pi^-$ and $\\pi^+$ shows a centrality dependency similar with the calculations with Chiral Magnetic Wave. The measurements of charge separation with respect to the reaction plane in search of Local Parity Violation and Chiral Magnetic Effect are also presented for Au+Au collisions at $\\sNN =$ 200, 62.4, 39, 27, 19.6, 11.5 and 7.7 GeV, and for U+U collisions at 193 GeV.

Gang Wang; for the STAR collaboration

2012-10-19T23:59:59.000Z

278

A functional magnetic resonance imaging study of overt letter verbal fluency using a clustered acquisition sequence: greater anterior cingulate activation with increased task demand  

E-Print Network (OSTI)

Regional cerebral activation during a cognitive task can vary with task demand and task performance. In a functional magnetic resonance imaging study, we examined the effect of manipulating task demand on activation during verbal fluency by using easy and hard letters. A clustered image acquisition sequence allowed overt verbal responses to be made in the absence of scanner noise which facilitated online measurement of task performance. Eleven righthanded, healthy male volunteers participated. Twice as many errors were produced with hard as with easy letters (20.8 ? 13.6 and 10.1 ? 10.7 % errors, respectively). For both conditions, the distribution of regional activation was comparable to that reported in studies of covert verbal fluency, but with greater engagement of subcortical areas. The hard condition was associated with greater dorsal anterior cingulate activation than the easy condition. This may reflect the greater demands of the former, particularly in terms of arousal responses with increased task difficulty and the monitoring of potential response errors. 2002 Elsevier Science (USA)

Cynthia H. Y. Fu; Kevin Morgan; John Suckling; Steve C. R. Williams; Chris Andrew; Goparlen N. Vythelingum; Philip K. Mcguire

2002-01-01T23:59:59.000Z

279

Urinary Tract Effects After Multifocal Nonthermal Irreversible Electroporation of the Kidney: Acute and Chronic Monitoring by Magnetic Resonance Imaging, Intravenous Urography and Urinary Cytology  

Science Conference Proceedings (OSTI)

Purpose: The nonthermal irreversible electroporation (NTIRE) is a novel potential ablation modality for renal masses. The aim of this study was the first evaluation of NTIRE's effects on the renal urine-collecting system using intravenous urography (IVU) and urinary cytology in addition to histology and magnetic resonance imaging (MRI). Methods: Eight percutaneous NTIRE ablations of the renal parenchyma, including the calyxes or pelvis, were performed in three male swine. MRI, IVU, histology, and urinary cytology follow-ups were performed within the first 28 days after treatment. Results: MRI and histological analysis demonstrated a localized necrosis 7 days and a localized scarification of the renal parenchyma with complete destruction 28 days after NTIRE. The urine-collecting system was preserved and showed urothelial regeneration. IVU and MRI showed an unaltered normal morphology of the renal calyxes, pelvis, and ureter. A new urinary cytology phenomenon featured a temporary degeneration by individual vacuolization of detached transitional epithelium cells within the first 3 days after NTIRE. Conclusions: This first urographical, urine-cytological, and MRI evaluation after porcine kidney NTIRE shows multifocal parenchyma destruction while protecting the involved urine-collecting system with regenerated urothelial tissue. NTIRE could be used as a targeted ablation method of centrally located renal masses.

Wendler, Johann Jakob, E-mail: johann.wendler@med.ovgu.de [University of Magdeburg, Department of Urology (Germany); Pech, Maciej [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Porsch, Markus; Janitzky, Andreas [University of Magdeburg, Department of Urology (Germany); Fischbach, Frank [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Buhtz, Peter; Vogler, Klaus [University of Magdeburg, Institute of Pathology (Germany); Huehne, Sarah [University of Magdeburg, Department of Urology (Germany); Borucki, Katrin [University of Magdeburg, Institute of Clinical Chemistry (Germany); Strang, Christof [University of Magdeburg, Department of Anaesthesiology (Germany); Mahnkopf, Dirk [Institute of Medical Technology and Research (Germany); Ricke, Jens [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Liehr, Uwe-Bernd [University of Magdeburg, Department of Urology (Germany)

2012-08-15T23:59:59.000Z

280

Unstable particles, gauge invariance and the Delta^{++} resonance parameters  

E-Print Network (OSTI)

The elastic and radiative pion(+)-proton scattering are studied in the framework of an effective Lagrangian model for the Delta^{++} resonance and its interactions. The finite width effects of this spin-3/2 resonance are introduced in the scattering amplitudes through a complex mass scheme to respect electromagnetic gauge invariance. The resonant pole (Delta^{++}) and background contributions (rho^0, sigma, Delta and neutron states) are separated according to the principles of the analytic S-matrix theory. The mass and width parameters of the \\Delta^{++} obtained from a fit to experimental data on the total cross section are in agreement with the results of a model-independent analysis based on the analytic S-matrix approach. The magnetic dipole moment determined from the radiative pion-proton scattering is mu_Delta^{++}=(6.14 +/- 0.51) nuclear magnetons.

G. Lopez Castro; A. Mariano

2003-02-24T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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281

Electric dipole-forbidden nuclear transitions driven by super-intense laser fields  

E-Print Network (OSTI)

Electric dipole-forbidden transitions of nuclei interacting with super-intense laser fields are investigated considering stable isotopes with suitable low-lying first excited states. Different classes of transitions are identified, and all magnetic sublevels corresponding to the near-resonantly driven nuclear transition are included in the description of the nuclear quantum system. We find that large transition matrix elements and convenient resonance energies qualify nuclear M1 transitions as good candidates for the coherent driving of nuclei. We discuss the implications of resonant interaction of intense laser fields with nuclei beyond the dipole approximation for the controlled preparation of excited nuclear states and important aspects of possible experiments aimed at observing these effects.

Adriana Plffy; Jrg Evers; Christoph H. Keitel

2007-10-31T23:59:59.000Z

282

In Vivo Near-Infrared Spectroscopy and Magnetic Resonance Imaging Monitoring of Tumor Response to Combretastatin A-4-Phosphate Correlated With Therapeutic Outcome  

Science Conference Proceedings (OSTI)

Purpose: To develop a combination treatment consisting of combretastatin A-4-phosphate (CA4P) with radiation based on tumor oxygenation status. Methods and Materials: In vivo near-infrared spectroscopy (NIRS) and diffusion-weighted (DW) magnetic resonance imaging (MRI) were applied to noninvasively monitor changes in tumor blood oxygenation and necrosis induced by CA4P (30 mg/kg) in rat mammary 13762NF adenocarcinoma, and the evidence was used to optimize combinations of CA4P and radiation treatment (a single dose of 5 Gy). Results: NIRS showed decreasing concentrations of tumor vascular oxyhemoglobin and total hemoglobin during the first 2 h after CA4P treatment, indicating significant reductions in tumor blood oxygenation and perfusion levels (p < 0.001). Twenty-four hours later, in response to oxygen inhalation, significant recovery was observed in tumor vascular and tissue oxygenation according to NIRS and pimonidazole staining results, respectively (p < 0.05). DW MRI revealed significantly increased water diffusion in tumors measured by apparent diffusion coefficient at 24 h (p < 0.05), suggesting that CA4P-induced central necrosis. In concordance with the observed tumor oxygen dynamics, we found that treatment efficacy depended on the timing of the combined therapy. The most significant delay in tumor growth was seen in the group of tumors treated with radiation while the rats breathed oxygen 24 h after CA4P administration. Conclusions: Noninvasive evaluation of tumor oxygen dynamics allowed us to rationally enhance the response of syngeneic rat breast tumors to combined treatment of CA4P with radiation.

Zhao Dawen, E-mail: Dawen.Zhao@UTSouthwestern.ed [Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Chang Chenghui [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Kim, Jae G.; Liu Hanli [Joint Program in Biomedical Engineering, University of Texas Arlington and University of Texas Southwestern Medical Center, Arlington, Texas (United States); Mason, Ralph P. [Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Joint Program in Biomedical Engineering, University of Texas Arlington and University of Texas Southwestern Medical Center, Arlington, Texas (United States)

2011-06-01T23:59:59.000Z

283

Industrial applications of photonuclear resonance excitation  

E-Print Network (OSTI)

Photonuclear resonance excitation refers to a variety of photonuclear interaction processes that lead to the excitation of a nucleus from some initial state to a higher energy nuclear state. Typical excited nuclear state ...

Chichester, David Lee, 1971-

2000-01-01T23:59:59.000Z

284

Coherent control of two nuclear spins using the anisotropic hyperfine interaction  

E-Print Network (OSTI)

We demonstrate coherent control of two nuclear spins mediated by the magnetic resonance of a hyperfine-coupled electron spin. This control is used to create a double nuclear coherence in one of the two electron spin manifolds, starting from an initial thermal state, in direct analogy to the creation of an entangled (Bell) state from an initially pure unentangled state. We identify challenges and potential solutions to obtaining experimental gate fidelities useful for quantum information processing in this type of system.

Yingjie Zhang; Colm A. Ryan; Raymond Laflamme; Jonathan Baugh

2011-07-14T23:59:59.000Z

285

The Next Challenge in X-Ray Science: Control of Resonant Electronic  

NLE Websites -- All DOE Office Websites (Extended Search)

The Next Challenge in X-Ray Science: Control of Resonant Electronic The Next Challenge in X-Ray Science: Control of Resonant Electronic Processes Wednesday, September 11, 2013 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Joachim Stöhr, LCLS My talk will give a historic perspective of the revolutionary science that was enabled by the advent of high power sources of coherent electromagnetic radiation and the implications for future scientific opportunities with x-ray free electron lasers (X-FELs). The historical journey starts with the development of radar microwave sources in the 1940s that fueled the development of nuclear magnetic resonance (NMR) techniques which by now have led to 6 Nobel Prizes. The theoretical description of NMR as coherent processes between nuclear states by Rabi and Bloch also provided the theoretical basis for the optical laser and its applications. Over the last

286

Magnetic Nanostructures for post-CMOS Electronics  

Science Conference Proceedings (OSTI)

... Using ferromagnetic resonance spectroscopy, we were able to separate edge behavior from bulk behavior in Permalloy magnetic nano-stripes. ...

2012-10-05T23:59:59.000Z

287

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

U in a mixture of depleted uranium and lead as a surrogateamounts of Pb and depleted uranium (DU). These targets actedprevious experiment, the depleted uranium in the target was

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

288

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

purposes. Presently, uranium enrichments are measured by oneweapons annually. Enrichment of uranium is necessary to makeof uranium isotopes in materials at enrichment facilities is

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

289

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

S.J. Thompson,Determining Plutonium in BIBLIOGRAPHY Spentweapons and power-reactor plutonium, Nature Vol. 283 (1980)Japans Spent Fuel and Plutonium Managament Challenges,

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

290

Magnetic resonance imaging in Mexico  

Science Conference Proceedings (OSTI)

MR imaging has experienced an important growth worldwide and in particular in the USA and Japan. This imaging technique has also shown an important rise in the number of MR imagers in Mexico. However

A. O. Rodriguez; R. Rojas; F. A. Barrios

2001-01-01T23:59:59.000Z

291

High Occurrence of Aberrant Lymph Node Spread on Magnetic Resonance Lymphography in Prostate Cancer Patients With a Biochemical Recurrence After Radical Prostatectomy  

SciTech Connect

Purpose: To investigate the pattern of lymph node spread in prostate cancer patients with a biochemical recurrence after radical prostatectomy, eligible for salvage radiotherapy; and to determine whether the clinical target volume (CTV) for elective pelvic irradiation in the primary setting can be applied in the salvage setting for patients with (a high risk of) lymph node metastases. Methods and Materials: The charts of 47 prostate cancer patients with PSA recurrence after prostatectomy who had positive lymph nodes on magnetic resonance lymphography (MRL) were reviewed. Positive lymph nodes were assigned to a lymph node region according to the guidelines of the Radiation Therapy Oncology Group (RTOG) for delineation of the CTV for pelvic irradiation (RTOG-CTV). We defined four lymph node regions for positive nodes outside this RTOG-CTV: the para-aortal, proximal common iliac, pararectal, and paravesical regions. They were referred to as aberrant lymph node regions. For each patient, clinical and pathologic features were recorded, and their association with aberrant lymph drainage was investigated. The distribution of positive lymph nodes was analyzed separately for patients with a prostate-specific antigen (PSA) <1.0 ng/mL. Results: MRL detected positive aberrant lymph nodes in 37 patients (79%). In 20 patients (43%) a positive lymph node was found in the pararectal region. Higher PSA at the time of MRL was associated with the presence of positive lymph nodes in the para-aortic region (2.49 vs. 0.82 ng/mL; p = 0.007) and in the proximal common iliac region (1.95 vs. 0.59 ng/mL; p = 0.009). There were 18 patients with a PSA <1.0 ng/mL. Ten of these patients (61%) had at least one aberrant positive lymph node. Conclusion: Seventy-nine percent of the PSA-recurrent patients had at least one aberrant positive lymph node. Application of the standard RTOG-CTV for pelvic irradiation in the salvage setting therefore seems to be inappropriate.

Meijer, Hanneke J.M., E-mail: H.Meijer@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Lin, Emile N. van [Department of Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Debats, Oscar A. [Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Witjes, J. Alfred [Department of Urology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Span, Paul N.; Kaanders, Johannes H.A.M. [Department of Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Barentsz, Jelle O. [Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands)

2012-03-15T23:59:59.000Z

292

Value of Diffusion-Weighted Magnetic Resonance Imaging for Prediction and Early Assessment of Response to Neoadjuvant Radiochemotherapy in Rectal Cancer: Preliminary Results  

Science Conference Proceedings (OSTI)

Purpose: To evaluate diffusion-weighted magnetic resonance imaging (DWI) for response prediction before and response assessment during and early after preoperative radiochemotherapy (RCT) for locally advanced rectal cancer (LARC). Methods and Materials: Twenty patients receiving RCT for LARC underwent MRI including DWI before RCT, after 10-15 fractions and 1 to 2 weeks before surgery. Tumor volume and apparent diffusion coefficient (ADC; b-values: 0-1000 s/mm{sup 2}) were determined at all time points. Pretreatment tumor ADC and volume, tumor ADC change ( Increment ADC), and volume change ( Increment V) between pretreatment and follow-up examinations were compared with histopathologic findings after total mesorectal excision (pathologic complete response [pCR] vs. no pCR, ypT0-2 vs. ypT3-4, T-downstaging or not). The discriminatory capability of pretreatment tumor ADC and volume, Increment ADC, and Increment V for the detection of pCR was compared with receiver operating characteristics analysis. Results: Pretreatment ADC was significantly lower in patients with pCR compared with patients without (in mm{sup 2}/s: 0.94 {+-} 0.12 Multiplication-Sign 10{sup -3} vs. 1.19 {+-} 0.22 Multiplication-Sign 10{sup -3}, p = 0.003), yielding a sensitivity of 100% and specificity of 86% for detection of pCR. The volume reduction during and after RCT was significantly higher in patients with pCR compared with patients without (in %: {Delta}V{sub during}: -62 {+-} 16 vs. -33 {+-} 16, respectively, p = 0.015; and {Delta}V{sub post}: -86 {+-} 12 vs. -60 {+-} 21, p = 0.012), yielding a sensitivity of 83% and specificity of 71% for the {Delta}V{sub during} and, respectively, 83% and 86% for the {Delta}V{sub post}. The Increment ADC during ({Delta}ADC{sub during}) and after RCT ({Delta}ADC{sub post}) showed a significantly higher value in patients with pCR compared with patients without (in %: {Delta}ADC{sub during}: 72 {+-} 14 vs. 16 {+-} 12, p = 0.0006; and {Delta}ADC{sub post}: 88 {+-} 35 vs. 26 {+-} 19, p = 0.0011), yielding a sensitivity and specificity of 100% for the {Delta}ADC{sub during} and, respectively, 100% and 93% for the {Delta}ADC{sub post}. Conclusions: These initial findings indicate that DWI, using pretreatment ADC, {Delta}ADC{sub during}, and {Delta}ADC{sub post} may be useful for prediction and early assessment of pathologic response to preoperative RCT of LARC, with higher accuracy than volumetric measurements.

Lambrecht, Maarten, E-mail: maarten.lambrecht@uzleuven.be [Department of Radiation Oncology, UZ Gasthuisberg, Leuven (Belgium); Vandecaveye, Vincent; De Keyzer, Frederik [Department of Radiology, UZ Gasthuisberg, Leuven (Belgium); Roels, Sarah [Department of Radiation Oncology, UZ Gasthuisberg, Leuven (Belgium); Penninckx, Freddy [Department of Abdominal Surgery, UZ Gasthuisberg, Leuven (Belgium); Van Cutsem, Eric [Department of Digestive Oncology, UZ Gasthuisberg, Leuven (Belgium); Filip, Claus [Department of Radiology, UZ Gasthuisberg, Leuven (Belgium); Haustermans, Karin [Department of Radiation Oncology, UZ Gasthuisberg, Leuven (Belgium)

2012-02-01T23:59:59.000Z

293

Electronuclear ion fusion in an ion cyclotron resonance reactor  

DOE Patents (OSTI)

A method and apparatus for generating nuclear fusion by ion cyclotron resonance in an ion trap reactor. The reactor includes a cylindrical housing having an axial axis, an internal surface, and first and second ends. First and second end plates that are charged are respectively located at the first and second ends of the cylindrical housing. A gas layer is adsorbed on the internal surface of the cylindrical housing. Ions are desorbed from the gas layer, forming a plasma layer adjacent to the cylindrical housing that includes first ions that have a same charge sign as the first and second end plates. A uniform magnetic field is oriented along the axial axis of the cylindrical housing. Second ions, that are unlike the first ions, but have the same charge sign, are injected into the cylindrical housing along the axial axis of the cylindrical housing. A radio frequency field resonantly accelerates the injected second ions at the cyclotron resonance frequency of the second ions. The second ions circulate in increasing helical orbits and react with the first ions, at the optimum energy for nuclear fusion. The amplitude of the radio frequency field is adjusted to accelerate the second ions at a rate equal to the rate of tangential energy loss of the second ions by nuclear scattering in the first ions, causing the ions to continually interact until fusion occurs.

Cowgill, Donald F.

1996-12-01T23:59:59.000Z

294

Energy levels and decoherence properties of single electron and nuclear spins in a defect center in diamond  

E-Print Network (OSTI)

The coherent behavior of the single electron and single nuclear spins of a defect center in diamond and a 13C nucleus in its vicinity, respectively, are investigated. The energy levels associated with the hyperfine coupling of the electron spin of the defect center to the 13C nuclear spin are analyzed. Methods of magnetic resonance together with optical readout of single defect centers have been applied in order to observe the coherent dynamics of the electron and nuclear spins. Long coherence times, in the order of microseconds for electron spins and tens of microseconds for nuclear spins, recommend the studied system as a good experimental approach for implementing a 2-qubit gate.

I. Popa; T. Gaebel; M. Domhan; C. Wittmann; F. Jelezko; J. Wrachtrup

2004-09-12T23:59:59.000Z

295

Coherence of an optically illuminated single nuclear spin qubit  

E-Print Network (OSTI)

We investigate the coherence properties of individual nuclear spin quantum bits in diamond [Dutt et al., Science, 316, 1312 (2007)] when a proximal electronic spin associated with a nitrogen-vacancy (NV) center is being interrogated by optical radiation. The resulting nuclear spin dynamics are governed by time-dependent hyperfine interaction associated with rapid electronic transitions, which can be described by a spin-fluctuator model. We show that due to a process analogous to motional averaging in nuclear magnetic resonance, the nuclear spin coherence can be preserved after a large number of optical excitation cycles. Our theoretical analysis is in good agreement with experimental results. It indicates a novel approach that could potentially isolate the nuclear spin system completely from the electronic environment.

Liang Jiang; M. V. Gurudev Dutt; Emre Togan; Lily Childress; Paola Cappellaro; Jacob M. Taylor; Mikhail D. Lukin

2007-07-09T23:59:59.000Z

296

Lensless Imaging of Magnetic Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

Wednesday, 28 March 2012 00:00 Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine....

297

Inhomogeneous magnetism in the doped kagome lattice of LaCuO2.66  

Science Conference Proceedings (OSTI)

The hole-doped kagome lattice of Cu2+ ions in LaCuO2.66 was investigated by nuclear quadrupole resonance (NQR), electron spin resonance (ESR), electrical resistivity, bulk magnetization and specific heat measurements. For temperatures above 180 K, the spin and charge properties show an activated behavior suggestive of a narrow-gap semiconductor. At lower temperatures, the results indicate an insulating ground state which may or may not be charge ordered. While the frustrated spins in remaining patches of the original kagome lattice might not be directly detected here, the observation of coexisting non-magnetic sites, free spins and frozen moments reveals an intrinsically inhomogeneous magnetism. Numerical simulations of a 1/3-diluted kagome lattice rationalize this magnetic state in terms of a heterogeneous distribution of cluster sizes and morphologies near the site-percolation threshold.

Julien, M.-H. [Laboratoire National des Champs Magnetiques Intenses; Simonet, V [Institut Neel, CNRS-UJF; Canals, B. [Institut Neel, CNRS-UJF; Garlea, Vasile O [ORNL; Bordet, Pierre [Laboratoire of Cristallographie, Grenoble; Darie, Celine [Laboratoire of Cristallographie, Grenoble

2013-01-01T23:59:59.000Z

298

Multiple resonant railgun power supply  

DOE Patents (OSTI)

A multiple repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. A plurality of serially connected paired parallel rails are powered by similar power supplies. Each supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles. The multiple serial operation permits relatively small energy components to deliver overall relatively large amounts of energy to the projectiles being propelled.

Honig, Emanuel M. (Los Alamos, NM); Nunnally, William C. (Los Alamos, NM)

1988-01-01T23:59:59.000Z

299

Multiple resonant railgun power supply  

DOE Patents (OSTI)

A multiple repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. A plurality of serially connected paired parallel rails are powered by similar power supplies. Each supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles. The multiple serial operation permits relatively small energy components to deliver overall relatively large amounts of energy to the projectiles being propelled.

Honig, E.M.; Nunnally, W.C.

1985-06-19T23:59:59.000Z

300

Cyclotron Resonances in Electron Cloud Dynamics  

Science Conference Proceedings (OSTI)

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lbstripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.

Celata, C. M.; Furman, Miguel A.; Vay, J.-L.; Ng, J. S.T.; Grote, D. P.; Pivi, M. T. F.; Wang, L. F.

2009-04-29T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Design and fabrication of a superconducting magnet for an 18 GHz electron cyclotron resonance ion/photon source NFRI-ECRIPS  

Science Conference Proceedings (OSTI)

A superconducting magnet was designed and fabricated for an 18 GHz ECR ion/photon source, which will be installed at National Fusion Research Institute (NFRI) in South Korea. The magnetic system consists of a set of four superconducting coils for axial mirror field and 36 pieces of permanent magnets for hexapolar field. The superconducting coils with a cryocooler (1.5 W - 4.2 K) allow one to reach peak mirror fields of 2.2 T in the injection and those of 1.5 T in the extraction regions on the source axis, and the resultant hexapolar field gives 1.35 T on the plasma chamber wall. The unbalanced magnetic force between the coils and surrounding yoke has been minimized to 16 ton by a coil arrangement and their electrical connection, and then was successfully suspended by 12 strong thermal insulating supports made of large numbers of carbon fibers. In order to block radiative thermal losses, multilayer thermal insulations are covered on the coil windings as well as 40-K aluminum thermal shield. Also new schemes of quench detection and safety system (coil divisions, quench detection coils, and heaters) were employed. For impregnation of the windings a special epoxy has been selected and treated to have a higher breaking strength and a higher thermal conductivity, which enables the superconductors to be uniformly and rapidly cooled down or heated during a quench.

You, H.-J.; Jang, S.-W.; Jung, Y.-H.; Lho, T.-H. [Convergence Plasma Research Center, National Fusion Research Institute, Yusung-gu, Daejeon (Korea, Republic of); Lee, S.-J. [The Theoretical Solutions, JHeng Inc., Seoul (Korea, Republic of)

2012-02-15T23:59:59.000Z

302

Resonant-cavity antenna for plasma heating  

DOE Patents (OSTI)

This invention relates generally to a method and apparatus for transferring energy to a plasma immersed in a magnetic field, and relates particularly to an apparatus for heating a plasma of low atomic number ions to high temperatures by transfer of energy to plasma resonances, particularly the fundamental and harmonics of the ion cyclotron frequency of the plasma ions. This invention transfers energy from an oscillating radio-frequency field to a plasma resonance of a plasma immersed in a magnetic field.

Perkins, F.W. Jr.; Chiu, S.C.; Parks, P.; Rawls, J.M.

1984-01-10T23:59:59.000Z

303

Cyclotron Resonances in Electron Cloud Dynamics  

SciTech Connect

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lb<< 2pi c/omega c (with lb = bunch length, omega c = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the electron cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor ~;;3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined vertical density"stripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.

Celata, C. M.; Furman, Miguel A.; Vay, J.-L.; Ng, J. S.T.; Grote, D. P.; Pivi, M. T. F.; Wang, L. F.

2009-04-29T23:59:59.000Z

304

JOURNAL DE PHYSIQUE Colloque C I, szrpplkment au no 2-3, Tome 32, Fkvrier-Mars 1971,page C 1 -1184 MAGNETIC EXCITATIONS IN Ni-DOPED KMnF,  

E-Print Network (OSTI)

River Nuclear Laboratories Atomic Energy of Canada Limited Chalk River, Ontario, Canada and R. H. W avecles observations. Abstract. - The magnetic excitations in a crystal of KMn0.97Nio.03F3 have been/ or resonant [2] impurity modes may occur. The measurements were carried out with a triple- axis crystal

Paris-Sud XI, Université de

305

Simulation of ion cyclotron resonance heating through resonant absorption in two-ion species plasma  

DOE Green Energy (OSTI)

Particle simulation of two-ion hybrid cyclotron resonance heating (ICRH) of a magnetized hydrogen plasma with deuteron minority by magnetosonic waves launched from the low magnetic field side is reported. Depending on the minority concentration, partial transmission and partial reflection of the incoming waves off the two-ion hybrid resonance layer occur, in contrast to the mode conversion mainly taking place during incidence from the high field side. Preferential minority heating is observed, as the minority cyclotron resonance is close to the two-ion hybrid resonance layer.

Tajima, T.; Riyopoulos, S.; Demchenko, V.

1987-01-01T23:59:59.000Z

306

RESONATOR PARTICLE SEPARATOR  

DOE Patents (OSTI)

A wave-guide resonator structure is designed for use in separating particles of equal momentum but differing in mass, having energies exceeding one billion eiectron volts. The particles referred to are those of sub-atomic size and are generally produced as a result of the bombardment of a target by a beam such as protons produced in a high energy accelerator. In the resonator a travelling electric wave is produced which travels at the same rate of speed as the unwanted particle which is thus deflected continuously over the length of the resonator. The wanted particle is slightly out of phase with the travelling wave so that over the whole length of the resonator it has a net deflection of substantially zero. The travelling wave is established in a wave guide of rectangular cross section in which stubs are provided to store magnetic wave energy leaving the electric wave energy in the main structure to obtain the desired travelling wave and deflection. The stubs are of such shape and spacing to establish a critical mathemitical relationship. (AEC)

Blewett, J.P.; Kiesling, J.D.

1963-06-11T23:59:59.000Z

307

Electron cyclotron resonance near the axis of the gas-dynamic trap  

SciTech Connect

Propagation of an extraordinary electromagnetic wave in the vicinity of electron cyclotron resonance surface in an open linear trap is studied analytically, taking into account inhomogeneity of the magnetic field in paraxial approximation. Ray trajectories are derived from a reduced dispersion equation that makes it possible to avoid the difficulty associated with a transition from large propagation angles to the case of strictly longitudinal propagation. Our approach is based on the theory, originally developed by Zvonkov and Timofeev [Sov. J. Plasma Phys. 14, 743 (1988)], who used the paraxial approximation for the magnetic field strength, but did not consider the slope of the magnetic field lines, which led to considerable error, as has been recently noted by Gospodchikov and Smolyakova [Plasma Phys. Rep. 37, 768-774 (2011)]. We have found ray trajectories in analytic form and demonstrated that the inhomogeneity of both the magnetic field strength and the field direction can qualitatively change the picture of wave propagation and significantly affect the efficiency of electron cyclotron heating of a plasma in a linear magnetic trap. Analysis of the ray trajectories has revealed a criterion for the resonance point on the axis of the trap to be an attractor for the ray trajectories. It is also shown that a family of ray trajectories can still reach the resonance point on the axis if the latter generally repels the ray trajectories. As an example, results of general theory are applied to the electron cyclotron resonance heating experiment which is under preparation on the gas dynamic trap in the Budker Institute of Nuclear Physics [Shalashov et al., Phys. Plasmas 19, 052503 (2012)].

Bagulov, D. S. [Novosibirsk State University, Pirogova Street 2, Novosibirsk (Russian Federation); Kotelnikov, I. A. [Novosibirsk State University, Pirogova Street 2, Novosibirsk (Russian Federation); Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences, Akademika Lavrentyeva Prospect 11, 630090 Novosibirsk (Russian Federation)

2012-08-15T23:59:59.000Z

308

Multipurpose superconducting electron cyclotron resonance ion source, the European roadmap to third-generation electron cyclotron resonance ion sources  

SciTech Connect

The major infrastructures of nuclear physics in Europe adopted the technology of electron cyclotron resonance (ECR) ion sources for the production of heavy-ion beams. Most of them use 14 GHz electron cyclotron resonance ion sources (ECRISs), except at INFN-LNS, where an 18 GHz superconducting ECRIS is in operation. In the past five years it was demonstrated, in the frame of the EU-FP5 RTD project called ''Innovative ECRIS,'' that further enhancement of the performances requires a higher frequency (28 GHz and above) and a higher magnetic field (above 2.2 T) for the hexapolar field. Within the EU-FP6 a joint research activity named ISIBHI has been established to build by 2008 two different ion sources, the A-PHOENIX source at LPSC Grenoble, reported in another contribution, and the multipurpose superconducting ECRIS (MS-ECRIS), based on fully superconducting magnets, able to operate in High B mode at a frequency of 28 GHz or higher. Such a development represents a significant step compared to existing devices, and an increase of typically a factor of 10 for the intensity is expected (e.g., 1 emA for medium charge states of heavy ions, or hundreds of e{mu}A of fully stripped light ions, or even 1 e{mu}A of charge states above 50{sup +} for the heaviest species). The challenging issue is the very high level of magnetic field, never achieved by a minimum B trap magnet system; the maximum magnetic field of MS-ECRIS will be higher than 4 or 5 T for the axial field and close to 2.7 T for the hexapolar field. The detailed description of the MS-ECRIS project and of its major constraints will be given along with the general issues of the developments under way.

Ciavola, G.; Gammino, S.; Celona, L.; Torrisi, L.; Passarello, S.; Ando, L.; Cavenago, M.; Galata, A.; Spaedtke, P.; Tinschert, K.; Lang, R.; Iannucci, R.; Leroy, R.; Barue, C.; Hitz, D.; Seyfert, P.; Koivisto, H.; Suominen, P.; Tarvainen, O.; Beijers, H. [Istituto Nazionale Fisica Nucleare-Laboratori Nazionali del Sud (INFN-LNS), Via S. Sofia 62, 95123 Catania (Italy) and INFN-Laboratori Nazionali di Legnaro (INFN-LNL), 35020 Legnaro (Italy); Gesellschaft fuer Schwerionenforschung mbH (GSI), 64291 Darmstadt (Germany); Grand Accelerateur National d'Ions Lourds (GANIL), 14076 Caen (France); CEA-DRFMC-SBT, 38054 Grenoble (France); Department of Physics, University of Jyvaeskylae (JYFL), 40014 Jyvaeskylae (Finland); Kernfysisch Versneller Instituut (KVI), 9747 AA Groningen (Netherlands); Svedberg Laboratory (TSL), 75121 Uppsala (Sweden); CERN AB Department, CERN CH-1211 Geneva (Switzerland); Hahn Meitner Institut Berlin GmbH (HMI), 14109 Berlin (Germany); National Institute of Physics and Nuclear Engineering (NIPNE), MG-6, Bucharest-Magurele (Romania)] (and others)

2006-03-15T23:59:59.000Z

309

A Novel Source of Tagged Low-Energy Nuclear Recoils  

E-Print Network (OSTI)

For sufficiently wide resonances, nuclear resonance fluorescence behaves like elastic photo-nuclear scattering while retaining the large cross-section characteristic of resonant photo-nuclear absorption. We show that NRF may be used to characterize the signals produced by low-energy nuclear recoils by serving as a novel source of tagged low-energy nuclear recoils. Understanding these signals is important in determining the sensitivity of direct WIMP dark-matter and coherent neutrino-nucleus scattering searches.

Joshi, Tenzing H Y

2011-01-01T23:59:59.000Z

310

Relationships between observed pore and pore-throat geometries, measured porosity and permeability, and indirect measures of pore volume by nuclear magnetic resonance  

E-Print Network (OSTI)

Carbonate reservoirs are a network of pores and connecting pore-throats that contain at least half of the world's oil. Genetic classification of carbonate pores enables one to map the pore types that have greatest influence on reservoir performance. Though NMR logging has been used to estimate pore sizes, it has not been used to identify genetic pore types or to aid in determinations of reservoir quality for different pore assemblages. Five genetic pore types identified in 40 carbonate and 7 sandstone samples were subjected to NMR measurements. Results reveal close correspondence between NMRderived pore volumes and 2-D pore size and shape gleaned from petrographic image analysis. Comparisons of real and synthetic pore shapes showed that shapes of all pore types in the medium size range of 0.02-0.5mm can be reliably compared with synthetic varieties, but such comparisons were unreliable for vuggy pores smaller than 0.5mm. T2 relaxation times for depositional pores exhibit low amplitude, narrow wavelength responses. Moldic pores produced medium amplitude, asymmetrical wavelength responses, and intercrystalline pores show high amplitude, narrow wavelength responses. NMR-derived pore volumes on pores with ferroan dolomite interiors underestimated pore diameter by up to 3 orders of magnitude. Calculated pore-throat sizes from MICP data correlate strongly with measured permeability. Samples with high, intermediate, or low poroperm values displayed characteristic T2 curves confirming that reservoir quality can be estimated from NMR measurements. Future work is expected to show that NMR logging can estimate reservoir quality at field scale and aid in mapping flow units in compartmentalized reservoirs.

Adams, Aaron J.

2005-12-01T23:59:59.000Z

311

Near Infrared Microspectroscopy, Fluorescence Microspectroscopy, Infrared Chemical Imaging and High Resolution Nuclear Magnetic Resonance Analysis of Soybean Seeds, Somatic Embryos and Single Cells  

E-Print Network (OSTI)

Novel methodologies are currently being developed and established for the chemical analysis of soybean seeds, embryos and single cells by Fourier Transform Infrared (FT-IR), Fourier Transform Near Infrared (FT-NIR) Microspectroscopy, Fluorescence and High-Resolution NMR (HR-NMR). The first FT-NIR chemical images of biological systems approaching one micron resolution are presented here. Chemical images obtained by FT-NIR and FT-IR Microspectroscopy are presented for oil in soybean seeds and somatic embryos under physiological conditions. FT-NIR spectra of oil and proteins were obtained for volumes as small as two cubic microns. Related, HR-NMR analyses of oil contents in somatic embryos are also presented here with nanoliter precision. Such 400 MHz 1H NMR analyses allowed the selection of mutagenized embryos with higher oil content (e.g. ~20%) compared to non-mutagenized control embryos. Moreover, developmental changes in single soybean seeds and/or somatic embryos may be monitored by FT-NIR with a precision ...

Baianu, I C; Hofmann, N E; Korban, S S; Lozano, P; You, T; AOCS 94th Meeting, Kansas

2002-01-01T23:59:59.000Z

312

Fourier Transform Near Infrared Microspectroscopy, Infrared Chemical Imaging, High-Resolution Nuclear Magnetic Resonance and Fluorescence Microspectroscopy Detection of Single Cancer Cells and Single Viral Particles  

E-Print Network (OSTI)

Single Cancer Cells from Human tumors are being detected and imaged by Fourier Transform Infrared (FT-IR), Fourier Transform Near Infrared (FT-NIR)Hyperspectral Imaging and Fluorescence Correlation Microspectroscopy. The first FT-NIR chemical, microscopic images of biological systems approaching one micron resolution are here reported. Chemical images obtained by FT-NIR and FT-IR Microspectroscopy are also presented for oil in soybean seeds and somatic embryos under physiological conditions. FT-NIR spectra of oil and proteins were obtained for volumes as small as two cubic microns. Related, HR-NMR analyses of oil contents in somatic embryos as well as 99% accurate calibrations are also presented here with nanoliter precision. Such high-resolution, 400 MHz H-1 NMR analyses allowed the selection of mutagenized embryos with higher oil content (e.g. >~20%) compared to the average levels in non-mutagenized control embryos. Moreover, developmental changes in single soybean seeds and/or somatic embryos may be monito...

Baianu,I C; Hofmann, N E; Korban, S S; Lozano, P; You, T

2004-01-01T23:59:59.000Z

313

A Large Sample Volume Magic Angle Spinning Nuclear Magnetic Resonance Probe for In-Situ Investigations with Constant Flow of Reactants  

SciTech Connect

A large-sample-volume constant-flow magic angle sample spinning (CF-MAS) NMR probe is reported for in-situ studies of the reaction dynamics, stable intermediates/transition states, and mechanisms of catalytic reactions. In our approach, the reactants are introduced into the catalyst bed using a fixed tube at one end of the MAS rotor while a second fixed tube, linked to a vacuum pump, is attached at the other end of the rotor. The pressure difference between both ends of the catalyst bed inside the sample cell space forces the reactants flowing through the catalyst bed, which improves the diffusion of the reactants and products. This design allows the use of a large sample volume for enhanced sensitivity and thus permitting in-situ 13C CF-MAS studies at natural abundance. As an example of application, we show that reactants, products and reaction transition states associated with the 2-butanol dehydration reaction over a mesoporous silicalite supported heteropoly acid catalyst (HPA/meso-silicalite-1) can all be detected in a single 13C CF-MAS NMR spectrum at natural abundance. Coke products can also be detected at natural 13C abundance and under the stopped flow condition. Furthermore, 1H CF-MAS NMR is used to identify the surface functional groups of HPA/meso-silicalite-1 under the condition of in-situ drying . We also show that the reaction dynamics of 2-butanol dehydration using HPA/meso-silicalite-1 as a catalyst can be explored using 1H CF-MAS NMR.

Hu, Jian Z.; Sears, Jesse A.; Mehta, Hardeep S.; Ford, Joseph J.; Kwak, Ja Hun; Zhu, Kake; Wang, Yong; Liu, Jun; Hoyt, David W.; Peden, Charles HF

2012-02-21T23:59:59.000Z

314

Ionization signals from electrons and alpha-particles in mixtures of liquid Argon and Nitrogen - perspectives on protons for Gamma Resonant Nuclear Absorption applications  

E-Print Network (OSTI)

In this paper we report on a detailed study of ionization signals produced by Compton electrons and alpha-particles in a Time Projection Chamber (TPC) flled with different mixtures of liquid Argon and Nitrogen. The measurements were carried out with Nitrogen concentrations up to 15% and a drift electric feld in the range 0-50 kV/cm. A prediction for proton ionization signals is made by means of interpolation. This study has been conducted in view of the possible use of liquid Ar-N2 TPCs for the detection of gamma-rays in the resonant band of the Nitrogen absorption spectrum, a promising technology for security and medical applications.

Zeller, M; Delaquis, S; Ereditato, A; Janos, S; Kreslo, I; Messina, M; Moser, U; Rossi, B

2010-01-01T23:59:59.000Z

315

Nuclear Data | More Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Computer Science Computer Science Theory, Modeling and Simulation Cyber Security Bioinformatics Climate & Environment Systems Biology Neutron Data Analysis and Visualization Nuclear Data Nuclear Systems Modeling and Simulation Supercomputing and Computation More Science Home | Science & Discovery | More Science | Computer Science | Nuclear Data SHARE Nuclear Data Nuclear Data ORNL is a recognized, international leader in nuclear data research and development (R&D) to support nuclear applications analyses. For more than 40 years, ORNL has provided neutron resonance region nuclear data evaluations to the US Evaluated Nuclear Data File (ENDF/B) database, and many of the key ORNL resonance evaluations have also been adopted by international nuclear databases in Europe, Japan, China, and Russia. ORNL

316

Cyclotron Resonances in Electron Cloud Dynamics  

SciTech Connect

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where l{sub b} << 2{pi}{omega}{sub c}, (l{sub b} = bunch duration, {omega}{sub c} = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor {approx} 3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined density 'stripes' of multipactoring found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations, the reason for the bunch-length dependence, and details of the dynamics will be discussed.

Celata, C M; Furman, M A; Vay, J L; Grote, D P; Ng, J T; Pivi, M F; Wang, L F

2009-05-05T23:59:59.000Z

317

Revealing the Degree of Magnetic Frustration by Non-Magnetic Impurities  

SciTech Connect

Imaging the magnetic fields around a non-magnetic impurity can provide a clear benchmark for quantifying the degree of magnetic frustration. Focusing on the strongly frustrated J{sub 1}-J{sub 2} model and the spatially anisotropic J{sub 1a}-J{sub 1b}-J{sub 2} model, very distinct low energy behaviors reflect different levels of magnetic frustration. In the J{sub 1}-J{sub 2} model, bound magnons appear trapped near the impurity in the ground state and strongly reduce the ordered moments for sites proximal to the impurity. In contrast, local moments in the J{sub 1a}-J{sub 1b}-J{sub 2} model are enhanced on the impurity neighboring sites. These theoretical predictions can be probed by experiments such as nuclear magnetic resonance and scanning tunneling microscopy, and the results can elucidate the role of frustration in antiferromagnets and help narrow the possible models to understand magnetism in the iron pnictdies.

Not Available

2011-08-12T23:59:59.000Z

318

Optimization of a microwave resonator cavity to perform electron spin resonance measurements on quantum dots  

E-Print Network (OSTI)

This thesis attempts to improve on an ongoing experiment of detecting electron spin resonance (ESR) on AlGaAs/GaAs lateral quantum dots. The experiment is performed in a 2.5 Tesla magnetic field at temperatures around ...

Burger, Anat

2006-01-01T23:59:59.000Z

319

Cyclotron Resonances in Electron Cloud Dynamics  

Science Conference Proceedings (OSTI)

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where l{sub b} stripes' of multipactoring found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations, the reason for the bunch-length dependence, and details of the dynamics will be discussed.

Celata, C M; Furman, M A; Vay, J L; Grote, D P; Ng, J T; Pivi, M F; Wang, L F

2009-05-05T23:59:59.000Z

320

Nuclear Data Sheets for A = 166  

E-Print Network (OSTI)

1978Ba78. , Q: from static nuclear orientation. Other :13 (1981Ma43) from static nuclear orientation. ABCD FGH 3 .magnetic spectrograph with nuclear emulsions, typical FWHM=

Baglin, Coral M

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

RESONATOR PARTICLE SEPARATOR  

DOE Patents (OSTI)

A wave guide resonator structure is described for use in separating particles of equal momentum but differing in mass and having energies exceeding one billion electron volts. The particles are those of sub-atomic size and are generally produced as a result of the bombardment of a target by a beam such as protons produced in a high-energy accelerator. In this wave guide construction, the particles undergo preferential deflection as a result of the presence of an electric field. The boundary conditions established in the resonator are such as to eliminate an interfering magnetic component, and to otherwise phase the electric field to obtain a traveling wave such as one which moves at the same speed as the unwanted particle. The latter undergoes continuous deflection over the whole length of the device and is, therefore, eliminated while the wanted particle is deflected in opposite directions over the length of the resonator and is thus able to enter an exit aperture. (AEC)

Blewett, J.P.

1962-01-01T23:59:59.000Z

322

ELECTRON PARAMAGNETIC RESONANCE ...  

Science Conference Proceedings (OSTI)

ELECTRON PARAMAGNETIC RESONANCE SPECTROELECTROCHEMISTRY OF TRANSITION METAL SOLAR FUELS CATALYSTS. ...

323

Preliminary development of thermal nuclear cell homogenization code  

SciTech Connect

Nuclear fuel cell homogenization for thermal reactors usually include three main parts, i.e., fast energy resonance part which usually adopt narrow resonance approximation to treat the resonance, low (intermediate) energy region in which the resonance can not be treated accurately using NR approximation and therefore we should use intermediate resonance treatment, and thermal energy region (very low) in which the effect of thermal must be treated properly. In n this study the application of the intermediate resonance approximation treatment for low energy nuclear resonance is discussed. The method is iterative based. As a sample the method is applied in U-235 low lying resonance and the result is presented and discussed.

Su'ud, Z.; Shafii, M. A.; Yudha, S. P.; Waris, A.; Rijal, K. [Nuclear Research group, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung40132 (Indonesia)

2012-06-06T23:59:59.000Z

324

Status of LDRD-DR 20070518 development of a magnetically driven target for thermo-nuclear burn studies (u)  

SciTech Connect

This project is developing a magnetically driven cylindrical confinement system for the creation of a small region of material existing under extreme conditions. Using a Ranchero High Explosive Pulsed Power generator (HEPP) with maximum current ranging from 25- 50 MA depending on the load, a current driven Al cylinder will impact a series of nested, less massive Au shells. Each subsequent shell's inner surface velocity will increase due to it's smaller mass by the ratio 2.01( 1+ m{sub i+ 1}/m i), along with radial convergence. Attaining this ideal result requires highly efficient energy transfer which in turn requires plastic cushions. The final velocity of the last sequential shell will be used to drive a central experimental package in which extreme material conditions will be produced. The inexpensive nature of HEPP and the extreme conditions attainable allow many studies to be conducted in regimes not currently available in the laboratory. One potential central experimental package consists of a cylindrical Inertial Confinement Fusion (ICF) target; a cylindrical Au pusher surrounding frozen DT. This target is used as a design tool. The ICF conditions achieved with such a target would be similar to those created in a double shell ignition capsule at the National Ignition Facility. The system being developed has a range of potential applications.

Watt, Robert G [Los Alamos National Laboratory; Atchison, W L [Los Alamos National Laboratory; Colgate, S A [Los Alamos National Laboratory; Gofoeth, J [Los Alamos National Laboratory; Griego, J [Los Alamos National Laboratory; Guzik, J [Los Alamos National Laboratory; Holtkamp, D [Los Alamos National Laboratory; Idzorek, G [Los Alamos National Laboratory; Kirkpatrick, R [Los Alamos National Laboratory; Menikoff, R [Los Alamos National Laboratory; Meyer, R [Los Alamos National Laboratory; Oona, H [Los Alamos National Laboratory; Reardon, P [Los Alamos National Laboratory; Rousculp, C L [Los Alamos National Laboratory; Sgro, A G [Los Alamos National Laboratory; Tabaka, L [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

325

Distribution of small dispersive coal dust particles and absorbed radioactive chemical elements in conditions of forced acoustic resonance in iodine air filter at nuclear power plant  

E-Print Network (OSTI)

The physical features of distribution of the small dispersive coal dust particles and the adsorbed radioactive chemical elements and their isotopes in the absorber with the granular filtering medium with the cylindrical coal granules were researched in the case of the intensive air dust aerosol stream flow through the iodine air filter (IAF). It was shown that, at the certain aerodynamic conditions in the IAF, the generation of the acoustic oscillations is possible. It was found that the acoustic oscillations generation results in an appearance of the standing acoustic waves of the air pressure (density) in the IAF. In the case of the intensive blow of the air dust aerosol, it was demonstrated that the standing acoustic waves have some strong influences on both: 1) the dynamics of small dispersive coal dust particles movement and their accumulation in the IAF; 2) the oversaturation of the cylindrical coal granules by the adsorbed radioactive chemical elements and their isotopes in the regions, where the antinodes of the acoustic waves are positioned. Finally, we completed the comparative analysis of the theoretical calculations with the experimental results, obtained for the cases of: 1) the experimental aerodynamic modeling of physical processes of the absorbed radioactive chemical elements and their isotopes distribution in the IAF; and 2) the gamma-activation spectroscopy analysis of the absorbed radioactive chemical elements and their isotopes distribution in the IAF. We made the innovative propositions on the necessary technical modifications with the purpose to improve the IAF technical characteristics and increase its operational time at the nuclear power plant (NPP), going from the completed precise characterization of the IAF parameters at the long term operation.

Oleg P. Ledenyov; Ivan M. Neklyudov

2013-06-14T23:59:59.000Z

326

Nonlinear coupling of nano mechanical resonators to Josephson quantum circuits  

E-Print Network (OSTI)

We propose a technique to couple the position operator of a nano mechanical resonator to a SQUID device by modulating its magnetic flux bias. By tuning the magnetic field properly, either linear or quadratic couplings can be realized, with a discretely adjustable coupling strength. This provides a way to realize coherent nonlinear effects in a nano mechanical resonator by coupling it to a Josephson quantum circuit. As an example, we show how squeezing of the nano mechanical resonator state can be realized with this technique. We also propose a simple method to measure the uncertainty in the position of the nano mechanical resonator without quantum state tomography.

Xingxiang Zhou; Ari Mizel

2006-05-01T23:59:59.000Z

327

Magnetic Centrifugal Mass Filter Abraham J. Fetterman and Nathaniel...  

NLE Websites -- All DOE Office Websites (Extended Search)

the centrifugal and magnetic confinement of ions, can be used to separate radioactive fission products from nuclear waste or from spent nuclear fuel in a nonproliferative manner....

328

Resonant-cavity antenna for plasma heating  

SciTech Connect

Disclosed is a resonant coil cavity wave launcher for energizing a plasma immersed in a magnetic field. Energization includes launching fast Alfven waves to excite ion cyclotron frequency resonances in the plasma. The cavity includes inductive and capacitive reactive members spaced no further than one-quarter wavelength from a first wall confinement chamber of the plasma. The cavity wave launcher is energized by connection to a waveguide or transmission line carrying forward power from a remote radio frequency energy source.

Perkins, Jr., Francis W. (Princeton, NJ); Chiu, Shiu-Chu (San Diego, CA); Parks, Paul (San Diego, CA); Rawls, John M. (Del Mar, CA)

1987-01-01T23:59:59.000Z

329

Laser Inertial Fusion-based Energy: Neutronic Design Aspects of a Hybrid Fusion-Fission Nuclear Energy System  

E-Print Network (OSTI)

for magnetic fusion reactors and IFMIF. Journal of NuclearFusion reactors blanket nucleonics. In Progress in NuclearFusion-Fission hybrid reactors. In Advances in Nuclear

Kramer, Kevin James

2010-01-01T23:59:59.000Z

330

ORNL Resonance Evaluation for ENDF/B-VII.1  

SciTech Connect

Cross-section evaluations in the resonance region are performed at Oak Ridge National Laboratory (ORNL) with the computer code SAMMY based on formalisms derived from the R-matrix theory. Resonance parameters (RPs) obtained in the evaluation, combined with resonance formalism, replicate a regression of the experimental data. The RPs are also used to generate cross-section data for neutron transport calculations in analyses of nuclear reactor design and nuclear criticality safety. In addition to generating RPs, the evaluation also generates the resonance parameter covariance (RPC) data. Several ORNL resonance evaluations, including RPs and RPCs, were incorporated in the recently released US-evaluated nuclear data library, ENDF/B-VII.1. A brief summary of the RPs and RPCs evaluated at ORNL is given.

Leal, Luiz C [ORNL; Guber, Klaus H [ORNL; Wiarda, Dorothea [ORNL; Arbanas, Goran [ORNL; Dunn, Michael E [ORNL

2012-01-01T23:59:59.000Z

331

Tissue oxymetry using magnetic resonance spectroscopy  

E-Print Network (OSTI)

A noninvasive method for in vivo measurement of tissue oxygen concentration has been developed. Several techniques currently used suffer limitations that prevent their practical clinical use. Our method is to use the ...

Liu, Lisa Chiawen

2005-01-01T23:59:59.000Z

332

ARTIFACTS IN MAGNETIC RESONANCE IMAGING FROM ...  

Science Conference Proceedings (OSTI)

... We surmise that the symmetric susceptibility artifact is ... It has two components, the first handling material ... the positive z-axis, the z-component of the ...

333

Radio-frequency quadrupole resonator for linear accelerator  

DOE Patents (OSTI)

An RFQ resonator for a linear accelerator having a reduced level of interfering modes and producing a quadrupole mode for focusing, bunching and accelerating beams of heavy charged particles, with the construction being characterized by four elongated resonating rods within a cylinder with the rods being alternately shorted and open electrically to the shell at common ends of the rods to provide an LC parallel resonant circuit when activated by a magnetic field transverse to the longitudinal axis.

Moretti, A.

1982-10-19T23:59:59.000Z

334

Magnetic Resonance of Hyperpolarised Helium-3 at Low Magnetic Fields.  

E-Print Network (OSTI)

??Dans ce travail nous avons tudi le problme du rapport signal bruit (RSB) en IRM trs bas champ magntique et explor des applications (more)

Safiullin, Kayum

2011-01-01T23:59:59.000Z

335

Coherence and control of quantum registers based on electronic spin in a nuclear spin bath  

E-Print Network (OSTI)

We consider a protocol for the control of few-qubit registers comprising one electronic spin embedded in a nuclear spin bath. We show how to isolate a few proximal nuclear spins from the rest of the environment and use them as building blocks for a potentially scalable quantum information processor. We describe how coherent control techniques based on magnetic resonance methods can be adapted to these electronic-nuclear solid state spin systems, to provide not only efficient, high fidelity manipulation of the registers, but also decoupling from the spin bath. As an example, we analyze feasible performances and practical limitations in a realistic setting associated with nitrogen-vacancy centers in diamond.

P. Cappellaro; L. Jiang; J. S. Hodges; M. D. Lukin

2009-01-05T23:59:59.000Z

336

Low-noise pulsed pre-polarization magnet system for ultra-low field NMR  

DOE Green Energy (OSTI)

A liquid cooled, pulsed electromagnet of solenoid configuration suitable for duty in an ultra-low field nuclear magnetic resonance system has been designed, fabricated and successfully operated. The magnet design minimizes Johnson noise, minimizes the hydrogen signal and incorporates minimal metal and no ferromagnetic materials. In addition, an acoustically quiet cooling system permitting 50% duty cycle operation was achieved by designing for single-phase, laminar flow, forced convection cooling. Winding, conductor splicing and epoxy impregnation techniques were successfully developed to produce a coil winding body with integral cooling passageways and adequate structural integrity. Issues of material compatibility, housing, coolant flow system and heat rejection system design will be discussed. Additionally, this pulsed electromagnet design has been extended to produce a boiling liquid cooled version in a paired solenoid configuration suitable for duty in an ultra-low field nuclear magnetic resonance system. This pair of liquid nitrogen cooled coils is currently being tested and commissioned. Issues of material compatibility, thermal insulation, thermal contraction, housing and coolant flow design are discussed.

Sims, James R [Los Alamos National Laboratory; Schilling, Josef B [Los Alamos National Laboratory; Swenson, Charles A [Los Alamos National Laboratory; Gardner, David L [Los Alamos National Laboratory; Matlashov, Andrei N [Los Alamos National Laboratory; Ammerman, Curti N [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

337

Nanomechanical resonance detector  

SciTech Connect

An embodiment of a nanomechanical frequency detector includes a support structure and a plurality of elongated nanostructures coupled to the support structure. Each of the elongated nanostructures has a particular resonant frequency. The plurality of elongated nanostructures has a range of resonant frequencies. An embodiment of a method of identifying an object includes introducing the object to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the object. An embodiment of a method of identifying a molecular species of the present invention includes introducing the molecular species to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the molecular species.

Grossman, Jeffrey C; Zettl, Alexander K

2013-10-29T23:59:59.000Z

338

Nuclear data for nuclear transmutation  

Science Conference Proceedings (OSTI)

Current status on nuclear data for the study of nuclear transmutation of radioactive wastes is reviewed

Hideo Harada

2009-01-01T23:59:59.000Z

339

Suppression of electric and magnetic fluctuations and improvement of confinement due to current profile modification by biased electrode in Saha Institute of Nuclear Physics tokamak  

Science Conference Proceedings (OSTI)

Improvement of plasma confinement is achieved in normal q{sub a} discharges of SINP-tokamak by introducing a biased electrode inside the last closed flux surface. All the important features of high confinement mode are observed biasing the electrode negatively with respect to the vacuum vessel. Arrays of electric and magnetic probes introduced in the edge plasma region reveal suppression of electric and magnetic fluctuations over distinct frequency ranges as well as modification of the toroidal current profile due to biasing. Further analysis identifies the electrostatic fluctuations to be due to drift mode and the magnetic fluctuations may be of slow compressional Alfven waves. Both get suppressed due to current profile modification during biasing, hence leading to the improvement of plasma confinement.

Basu, Debjyoti; Pal, Rabindranath [Saha Institute of Nuclear Physics, 1/AF-Bidhannagar, Kolkata 700064 (India); Ghosh, Joydeep; Chattopadhyay, Prabal K. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2012-07-15T23:59:59.000Z

340

Moment free toroidal magnet  

DOE Patents (OSTI)

A toroidal magnet for confining a high magnetic field for use in fusion reactor research and nuclear particle detection. The magnet includes a series of conductor elements arranged about and fixed at its small major radius portion to the outer surface of a central cylindrical support each conductor element having a geometry such as to maintain the conductor elements in pure tension when a high current flows therein, and a support assembly which redistributes all or part of the tension which would otherwise arise in the small major radius portion of each coil element to the large major radius portion thereof.

Bonanos, Peter (East Brunswick, NJ)

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Electromagnetic studies of nuclear structure and reactions  

SciTech Connect

This report contains papers on the following topics: giant resonance studies; deep inelastic scattering studies; high resolution nuclear structure work; and relativistic RPA; and field theory in the Schroedinger Representation.

Hersman, F.W.; Dawson, J.F.; Heisenberg, J.H.; Calarco, J.R.

1990-06-01T23:59:59.000Z

342

Spin rotation and birefringence effect for a particle in a high energy storage ring and measurement of the real part of the coherent elastic zero-angle scattering amplitude, electric and magnetic polarizabilities  

E-Print Network (OSTI)

In the present paper the equations for the spin evolution of a particle in a storage ring are analyzed considering contributions from the tensor electric and magnetic polarizabilities of the particle. Study of spin rotation and birefringence effect for a particle in a high energy storage ring provides for measurement as the real part of the coherent elastic zero-angle scattering amplitude as well as tensor electric and magnetic polarizabilities. We proposed the method for measurement the real part of the elastic coherent zero-angle scattering amplitude of particles and nuclei in a storage ring by the paramagnetic resonance in the periodical in time nuclear pseudoelectric and pseudomagnetic fields.

V. G. Baryshevsky; A. A. Gurinovich

2005-06-14T23:59:59.000Z

343

Nuclear Photonics  

E-Print Network (OSTI)

With new gamma-beam facilities like MEGa-ray at LLNL (USA) or ELI-NP at Bucharest with 10^13 g/s and a bandwidth of Delta E_g/E_g ~10^-3, a new era of g-beams with energies Duke Univ., USA) with 10^8 g/s and Delta E_g/E_g~0.03. Even a seeded quantum FEL for g-beams may become possible, with much higher brilliance and spectral flux. At the same time new exciting possibilities open up for focused g-beams. We describe a new experiment at the g-beam of the ILL reactor (Grenoble), where we observed for the first time that the index of refraction for g-beams is determined by virtual pair creation. Using a combination of refractive and reflective optics, efficient monochromators for g-beams are being developed. Thus we have to optimize the system of the g-beam facility, the g-beam optics and g-detectors. We can trade g-intensity for band width, going down to Delta E_g/E_g ~ 10^-6 and address individual nuclear levels. 'Nuclear photonics' stresses the importance of nuclear applications. We can address with g-beams individual nuclear isotopes and not just elements like with X-ray beams. Compared to X rays, g-beams can penetrate much deeper into big samples like radioactive waste barrels, motors or batteries. We can perform tomography and microscopy studies by focusing down to micron resolution using Nucl. Reson. Fluorescence for detection with eV resolution and high spatial resolution. We discuss the dominating M1 and E1 excitations like scissors mode, two-phonon quadrupole octupole excitations, pygmy dipole excitations or giant dipole excitations under the new facet of applications. We find many new applications in biomedicine, green energy, radioactive waste management or homeland security. Also more brilliant secondary beams of neutrons and positrons can be produced.

D. Habs; M. M. Guenther; M. Jentschel; P. G. Thirolf

2012-01-21T23:59:59.000Z

344

Nuclear & Uranium  

U.S. Energy Information Administration (EIA)

Nuclear & Uranium. Uranium fuel ... nuclear reactors, generation, spent fuel. Total Energy. Comprehensive data summaries, comparisons, analysis, and projections ...

345

Nuclear power and nuclear weapons  

SciTech Connect

The proliferation of nuclear weapons and the expanded use of nuclear energy for the production of electricity and other peaceful uses are compared. The difference in technologies associated with nuclear weapons and nuclear power plants are described.

Vaughen, V.C.A.

1983-01-01T23:59:59.000Z

346

Magnetic chicane for terahertz management  

DOE Patents (OSTI)

The introduction of a magnetic electron beam orbit chicane between the wiggler and the downstream initial bending dipole in an energy recovering Linac alleviates the effects of radiation propagated from the downstream bending dipole that tend to distort the proximate downstream mirror of the optical cavity resonator.

Benson, Stephen (Yorktown, VA); Biallas, George Herman (Yorktown, VA); Douglas, David (Yorktown, VA); Jordan, Kevin Carl (Newport News, VA); Neil, George R. (Williamsburg, VA); Michelle D. Shinn (Newport News, VA); Willams, Gwyn P. (Yorktown, VA)

2010-12-28T23:59:59.000Z

347

MaxEnt-Burg Application to Muon-Spin Resonance  

SciTech Connect

Muon-Spin Rotation ({mu}SR) is an experimental technique similar to Nuclear Magnetic Resonance (NMR). {mu}SR data are recorded as a set of time-series histograms of muon-decay events. Both {mu}SR and NMR regularly produce signals that are overlapping, weak and/or broadened in frequency space. These {mu}SR histograms are usually analyzed by curve fitting and Fourier transformations. However, several NMR and {mu}SR groups have developed Maximum Entropy (MaxEnt, ME) applications to improve the sensitivity of the time series analysis. We have focused on the application of the ME-Burg algorithm. The optimal number of autoregression coefficients is between N/3 and N/5 where N is the total number of data points. Selected results for simulated data and real data ME-{mu}SR applications are reported. Most of our {mu}SR work is for cuprate superconductor studies. The strength of the ME-Burg algorithm is fully used, as there is a clear relationship between the muon-spin signal S(i) at any time i and the signals S(i-k) at earlier times. ME-Burg has the major advantage of producing in the frequency transform only structure for which sufficient statistical evidence is present.

Boekema, C.; Browne, M. C. [Department of Physics and Astronomy, San Jose State University, San Jose CA 95192-0106 (United States)

2008-11-06T23:59:59.000Z

348

Related Resources - Nuclear Data Program, Nuclear Engineering...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

349

Publications: Other Resources - Nuclear Data Program - Nuclear...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

350

Publications 2005 - Nuclear Data Program - Nuclear Engineering...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

351

Publications 2003 - Nuclear Data Program - Nuclear Engineering...  

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Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

352

Contacts - Nuclear Data Program, Nuclear Engineering Division...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

353

Publications 2001 - Nuclear Data Program - Nuclear Engineering...  

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Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

354

Publications 2004 - Nuclear Data Program - Nuclear Engineering...  

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Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

355

Publications 2009 - Nuclear Data Program - Nuclear Engineering...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

356

Nuclear Criticality Safety: Current Activities - Nuclear Engineering...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

357

Nuclear Criticality Safety - Nuclear Engineering Division (Argonne...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

358

Nuclear Systems Analysis - Nuclear Engineering Division (Argonne...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

359

Publications 2011 - Nuclear Data Program - Nuclear Engineering...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

360

Regarding Confinement Resonances  

NLE Websites -- All DOE Office Websites (Extended Search)

Regarding Confinement Resonances Regarding Confinement Resonances Regarding Confinement Resonances Print Wednesday, 27 July 2011 00:00 When an atom is encapsulated inside a hollow spherical carbon buckyball, the complex is called an "endofullerene." Theoretically, if the atom is an unreactive noble gas like xenon, it should be centered within the cage. If one or more of the atom's electrons are boosted out of the cage by an x-ray photon, the electron waves may be transmitted through or reflected off the carbon cage, giving rise to an interference effect similar to waves in a water tank. These so-called "confinement resonances" were predicted theoretically a decade ago but have never been observed. In the first experimental test of this theory, members of an international team led by Ronald Phaneuf, University of Nevada, and working at ALS Beamline 10.0.1 produced and isolated xenon endofullerenes and observed confinement resonances.

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Resonant snubber inverter  

DOE Patents (OSTI)

A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 14 figs.

Lai, J.S.; Young, R.W. Sr.; Chen, D.; Scudiere, M.B.; Ott, G.W. Jr.; White, C.P.; McKeever, J.W.

1997-06-24T23:59:59.000Z

362

Resonant snubber inverter  

DOE Patents (OSTI)

A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.

Lai, Jih-Sheng (Knoxville, TN); Young, Sr., Robert W. (Oak Ridge, TN); Chen, Daoshen (Knoxville, TN); Scudiere, Matthew B. (Oak Ridge, TN); Ott, Jr., George W. (Knoxville, TN); White, Clifford P. (Knoxville, TN); McKeever, John W. (Oak Ridge, TN)

1997-01-01T23:59:59.000Z

363

Superconducting Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

magnet technology has allowed physicists to attain higher energies in circular accelerators. One can obtain higher magnetic fields because there is no resistance in a...

364

Resonant Kicker System Development at SLAC  

DOE Green Energy (OSTI)

The design and installation of the Linear Coherent Light Source [1] at SLAC National Accelerator Laboratory has included the development of a kicker system for selective beam bunch dumping. The kicker is based on an LC resonant topology formed by the 50 uF energy storage capacitor and the 64 uH air core magnet load which has a sinusoidal pulse period of 400us. The maximum magnet current is 500 A. The circuit is weakly damped, allowing most of the magnet energy to be recovered in the energy storage capacitor. The kicker runs at a repetition rate of 120Hz. A PLC-based control system provides remote control and monitoring of the kicker via EPICS protocol. Fast timing and interlock signals are converted by discrete peak-detect and sample-hold circuits into DC signals that can be processed by the PLC. The design and experimental characterization of the system are presented.

Beukers, Tony; Krzaszczak, John; Larrus, Marc; Lira, Antonio de; /SLAC

2009-04-27T23:59:59.000Z

365

Nuclear effects in atomic transitions  

E-Print Network (OSTI)

Atomic electrons are sensitive to the properties of the nucleus they are bound to, such as nuclear mass, charge distribution, spin, magnetization distribution, or even excited level scheme. These nuclear parameters are reflected in the atomic transition energies. A very precise determination of atomic spectra may thus reveal information about the nucleus, otherwise hardly accessible via nuclear physics experiments. This work reviews theoretical and experimental aspects of the nuclear effects that can be identified in atomic structure data. An introduction to the theory of isotope shifts and hyperfine splitting of atomic spectra is given, together with an overview of the typical experimental techniques used in high-precision atomic spectroscopy. More exotic effects at the borderline between atomic and nuclear physics, such as parity violation in atomic transitions due to the weak interaction, or nuclear polarization and nuclear excitation by electron capture, are also addressed.

Plffy, Adriana

2011-01-01T23:59:59.000Z

366

High power variable couplers for ladder and spoke type resonators  

Science Conference Proceedings (OSTI)

Superconducting RF structures such as spoke resonators [1] have been developed which will accelerate very low velocity ions. This opens up the possibility for the use of these resonators in high power proton accelerators at energies as low as the output energies of typical RFQs. Most similar resonators have been used for the acceleration of ions requiring only low RF power input. In new applications such as for the Accelerator Transmutation of Nuclear Wastes (ATW) and Accelerator Production of Tritium (APT), higher RF power will be required because of the larger beam currents. This paper discusses some higher power variable coupler concepts that could be used with these structures.

Spalek, G. (George); Kuzminski, J. (Jozef)

2001-01-01T23:59:59.000Z

367

Quantization of Atomic and Nuclear Rest Masses  

E-Print Network (OSTI)

We were able to quantize phenomenologically the first time the atomic and nuclear rest masses. Note that this quantization rule is justified for atoms and nuclei with different A, N and Z and the nuclei and atoms represent a coherent synchronized systems - a complex of coupled oscillators (resonators). The cooperative resonance synchronization mechanisms are responsible for explanation of how the electron volt world can influence the nuclear mega electron volt world. It means that we created new possibilities for inducing and controlling nuclear reactions by atomic processes.

F. A. Gareev; G. F. Gareeva; I. E. Zhidkova

2007-08-02T23:59:59.000Z

368

ELECTRON PARAMAGNETIC RESONANCE IN BIOLOGY  

E-Print Network (OSTI)

published in Perspectives in Biology and Medicine. ) 51. D.PARAMAGNETIC RESONANCE IN BIOLOGY G. M. Androes and Melvinparamagnetic resonance in biology is presented, including a

Androes, G.M.; Calvin, Melvin.

2008-01-01T23:59:59.000Z

369

Giant resonance study by 6li scattering  

E-Print Network (OSTI)

Nuclear incompressibility Knm is an important parameter in the nuclear matter equation of state (EOS). The locations of the isocalar giant monopole resonance (ISGMR) and giant dipole resonance (ISGDR) of nuclei are directly related to Knm and thus can give the most effective constraint on the value of the Knm. In order to determine Knm accurately, a systematic study of the ISGMR and ISGDR over a wide range of nuclei is necessary. Alpha inelastic scattering at small angles has been successfully used to study the ISGMR of heavy and medium nuclei where the monopole resonance is concentrated in a broad peak. For light nuclei (Aradioactive nuclei with inverse reactions using 6Li as a target. Data for elastic scattering of 240 MeV 6Li ions and inelastic scattering to low-lying states and giant resonances was taken for 24Mg, 28Si and 116Sn. A data analysis procedure was developed for double folding calculations. The optical potential parameters for 6Li + 24Mg, 6Li + 28Si and 6Li + 116Sn scattering systems were obtained by fitting elastic scattering data. Multipole analyses were carried out for inelastic scattering to high lying isoscalar giant resonances with multipolarities L=0 - 3. The results for the ISGMR and ISGQR are in agreement with those obtained with 240 MeV ? scattering, however the agreement for the ISGDR and HEOR is not so good, indicating the uncertainty in extracting these strengths. This work has shown that 240 MeV 6Li scattering is a viable way to study the ISGMR and ISGQR and can be particularly useful in rare isotope studies where 6Li can be used as the target.

Chen, Xinfeng

2008-05-01T23:59:59.000Z

370

A Potential Approach to Address Materials Aging Issues in Nuclear ...  

Science Conference Proceedings (OSTI)

Potential applications of this technology for nuclear reactor aystems will be ... First-Principles Theory of Magnetism, Crystal Field and Phonon Spectrum of UO2 .

371

Light Water Reactor Materials for Commercial Nuclear Power ...  

Science Conference Proceedings (OSTI)

Presentation Title, Light Water Reactor Materials for Commercial Nuclear ... First- Principles Theory of Magnetism, Crystal Field and Phonon Spectrum of UO2.

372

Spin resonance strength calculations  

SciTech Connect

In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

Courant,E.D.

2008-10-06T23:59:59.000Z

373

Doing Research at An Office of Research Workshop  

E-Print Network (OSTI)

..............................................................................................12 CITI Training Courses............................................................................................................25 Nuclear Magnetic Resonance (NMR) Core Facility

Salama, Khaled

374

Nuclear Chemistry Beta decay of 71,73  

E-Print Network (OSTI)

34 Nuclear Chemistry Beta decay of 71,73 Co: probing single-parti- cle states approaching doubly of primary interest are the nuclear magnetic dipole moment and nuclear electric quadrupole moment. The dipole/or neutrons in the nucleus. The dipole moment provides information on the nuclear quantum structure

Mantica, Paul F.

375

Nuclear Reactions  

NLE Websites -- All DOE Office Websites (Extended Search)

Reactions Nuclear reactions and nuclear scattering are used to measure the properties of nuclei. Reactions that exchange energy or nucleons can be used to measure the energies of...

376

Nuclear Safety  

Energy.gov (U.S. Department of Energy (DOE))

Nuclear Safety information site that provides assistance and resources to field elements in implementation of requirements and resolving nuclear safety, facility safety, and quality assurance issues.

377

Nuclear Materials  

Science Conference Proceedings (OSTI)

Materials and Fuels for the Current and Advanced Nuclear Reactors III ... response of oxide ceramics for nuclear applications through experiment, theory, and...

378

Deuteron Spin Structure Functions in the Resonance and DIS Regions  

SciTech Connect

We derive relations between spin-dependent nuclear and nucleon g_1 and g_2 structure functions, valid at all Q^2, and in both the resonance and deep inelastic regions. We apply the formalism to the specific case of the deuteron, which is often used as a source of neutron structure information, and compare the size of the nuclear corrections calculated using exact kinematics and using approximations applicable at large Q^2.

S. Kulagin; W. Melnitchouk

2007-10-03T23:59:59.000Z

379

Regarding Confinement Resonances  

NLE Websites -- All DOE Office Websites (Extended Search)

Regarding Confinement Resonances Print Regarding Confinement Resonances Print When an atom is encapsulated inside a hollow spherical carbon buckyball, the complex is called an "endofullerene." Theoretically, if the atom is an unreactive noble gas like xenon, it should be centered within the cage. If one or more of the atom's electrons are boosted out of the cage by an x-ray photon, the electron waves may be transmitted through or reflected off the carbon cage, giving rise to an interference effect similar to waves in a water tank. These so-called "confinement resonances" were predicted theoretically a decade ago but have never been observed. In the first experimental test of this theory, members of an international team led by Ronald Phaneuf, University of Nevada, and working at ALS Beamline 10.0.1 produced and isolated xenon endofullerenes and observed confinement resonances.

380

Regarding Confinement Resonances  

NLE Websites -- All DOE Office Websites (Extended Search)

Regarding Confinement Resonances Print Regarding Confinement Resonances Print When an atom is encapsulated inside a hollow spherical carbon buckyball, the complex is called an "endofullerene." Theoretically, if the atom is an unreactive noble gas like xenon, it should be centered within the cage. If one or more of the atom's electrons are boosted out of the cage by an x-ray photon, the electron waves may be transmitted through or reflected off the carbon cage, giving rise to an interference effect similar to waves in a water tank. These so-called "confinement resonances" were predicted theoretically a decade ago but have never been observed. In the first experimental test of this theory, members of an international team led by Ronald Phaneuf, University of Nevada, and working at ALS Beamline 10.0.1 produced and isolated xenon endofullerenes and observed confinement resonances.

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Regarding Confinement Resonances  

NLE Websites -- All DOE Office Websites (Extended Search)

Regarding Confinement Resonances Print Regarding Confinement Resonances Print When an atom is encapsulated inside a hollow spherical carbon buckyball, the complex is called an "endofullerene." Theoretically, if the atom is an unreactive noble gas like xenon, it should be centered within the cage. If one or more of the atom's electrons are boosted out of the cage by an x-ray photon, the electron waves may be transmitted through or reflected off the carbon cage, giving rise to an interference effect similar to waves in a water tank. These so-called "confinement resonances" were predicted theoretically a decade ago but have never been observed. In the first experimental test of this theory, members of an international team led by Ronald Phaneuf, University of Nevada, and working at ALS Beamline 10.0.1 produced and isolated xenon endofullerenes and observed confinement resonances.

382

Regarding Confinement Resonances  

NLE Websites -- All DOE Office Websites (Extended Search)

off the carbon cage, giving rise to an interference effect similar to waves in a water tank. These so-called "confinement resonances" were predicted theoretically a decade ago but...

383

Cylindrical laser resonator  

DOE Patents (OSTI)

The properties of an improved class of lasers is presented. In one configuration of these lasers the radiation propagates radially within the amplifying medium, resulting in high fields and symmetric illumination at the resonator axis. Thus there is a strong focusing of energy at the axis of the resonator. In a second configuration the radiation propagates back and forth in a tubular region of space.

Casperson, Lee W. (Los Angeles, CA)

1976-02-24T23:59:59.000Z

384

MAGNETIC NEUTRON SCATTERING  

SciTech Connect

Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern science, ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3.

ZALIZNYAK,I.A.; LEE,S.H.

2004-07-30T23:59:59.000Z

385

Resonant nonlinear ultrasound spectroscopy  

DOE Patents (OSTI)

Components with defects are identified from the response to strains applied at acoustic and ultrasound frequencies. The relative resonance frequency shift .vertline..DELTA..function./.function..sub.0.vertline., is determined as a function of applied strain amplitude for an acceptable component, where .function..sub.0 is the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak of a selected mode to determine a reference relationship. Then, the relative resonance frequency shift .vertline..DELTA..function./.function..sub.0 is determined as a function of applied strain for a component under test, where fo .function..sub.0 the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak to determine a quality test relationship. The reference relationship is compared with the quality test relationship to determine the presence of defects in the component under test.

Johnson, Paul A. (Santa Fe, NM); TenCate, James A. (Los Alamos, NM); Guyer, Robert A. (Amherst, MA); Van Den Abeele, Koen E. A. (Sint-Niklaas, BE)

2001-01-01T23:59:59.000Z

386

Fabrication of 3-D cubic unit cells with measured IR resonances.  

Science Conference Proceedings (OSTI)

3-D cubic unit cell arrays containing split ring resonators were fabricated and characterized. The unit cells are {approx}3 orders-of-magnitude smaller than microwave SRR-based metamaterials and exhibit both electrically and magnetically excited resonances for normally incident TEM waves in addition to showing improved isotropic response.

Ellis, A. Robert; Sinclair, Michael B.; Brener, Igal; Wendt, Joel Robert; Burckel, David Bruce; Ginn, James Cleveland, III; Ten Eyck, Gregory A.

2010-03-01T23:59:59.000Z

387

Nuclear Matter and Nuclear Dynamics  

E-Print Network (OSTI)

Highlights on the recent research activity, carried out by the Italian Community involved in the "Nuclear Matter and Nuclear Dynamics" field, will be presented.

M Colonna

2009-02-26T23:59:59.000Z

388

Magnetics Publications  

Science Conference Proceedings (OSTI)

... Resonant microwave power absorption and relaxation of the energy levels of ... Kim, ZN Utegulov, JM Shaw, and BT Draine, "Optimization of Arrays of ...

2013-08-18T23:59:59.000Z

389

Atomic Devices and Instrumentation Group  

Science Conference Proceedings (OSTI)

... 2001 and 2005, demonstrated an atomic clock physics package with ... magnetometers for magnetic anomaly detection, nuclear magnetic resonance ...

2013-08-09T23:59:59.000Z

390

Proceedings of the international conference on nuclear physics, August 24-30, 1980, Berkeley, California. Volume 1. Abstracts. [Berkeley, California, August 24-30, 1980 (abstracts only)  

SciTech Connect

This volume contains all abstracts (931) received by the conference organizers before June 20, 1980. The abstracts are grouped according to the following topics: nucleon-nucleon interactions, free and in nuclei; distribution of matter, charge, and magnetism; exotic nuclei and exotic probes; giant resonances and other high-lying excitations; applications of nuclear science; nuclei with large angular momentum and deformation; heavy-ion reactions and relaxation phenomena; new techniques and instruments; pion absorption and scattering by nuclei; and miscellaneous. Some of these one-page abstracts contain data. A complete author index is provided. (RWR)

1980-01-01T23:59:59.000Z

391

Theoretical nuclear physics  

SciTech Connect

This report discusses the following topics: Exact 1-loop vacuum polarization effects in 1 + 1 dimensional QHD; exact 1-fermion loop contributions in 1 + 1 dimensional solitons; exact scalar 1-loop contributions in 1 + 3 dimensions; exact vacuum calculations in a hyper-spherical basis; relativistic nuclear matter with self- consistent correlation energy; consistent RHA-RPA for finite nuclei; transverse response functions in the {triangle}-resonance region; hadronic matter in a nontopological soliton model; scalar and vector contributions to {bar p}p {yields} {bar {Lambda} {Lambda}} reaction; 0+ and 2+ strengths in pion double-charge exchange to double giant-dipole resonances; and nucleons in a hybrid sigma model including a quantized pion field.

Rost, E.; Shephard, J.R.

1992-08-01T23:59:59.000Z

392

Real-time high-resolution X-ray imaging and nuclear magnetic resonance study of the hydration of pure and Na-doped C3A in the presence of sulfates  

E-Print Network (OSTI)

1992. 9. Mehta PK, Monteiro PJM. Concrete - Microstructure,Emwas c , J. L. Provis d and P.J.M. Monteiro e a Department16. Silva DA, Monteiro PJM. Early Formation of Ettringite in

Kirchheim,, A. P.

2012-01-01T23:59:59.000Z

393

UNCORRECTED 2 Simulation of robust resonance parameters using information theory  

E-Print Network (OSTI)

UNCORRECTED PROOF 1 2 Simulation of robust resonance parameters using information theory 3 P.T. Krishna Kumar a,*, V.V. Phoha b , S.S. Iyengar c 4 a Reactor Physics Division, Indira Gandhi Centre systematic errors in cross-section 13 measurement, correlation due to nuclear reaction formalism, etc. All

Phoha, Vir V.

394

Nuclear data and related services  

SciTech Connect

National Nuclear Data Center (NNDC) maintains a number of data bases containing bibliographic information and evaluated as well as experimental nuclear properties. An evaluated computer file maintained by the NNDC, called the Evaluated Nuclear Structure Data File (ENSDF), contains nuclear structure information for all known nuclides. The ENSDF is the source for the journal ''Nuclear Data Sheets'' which is produced and edited by NNDC. The Evaluated Nuclear Data File (ENDF), on the other hand is designed for storage and retrieval of such evaluated nuclear data as are used in neutronic, photonic, and decay heat calculations in a large variety of applications. Some of the publications from these data bases are the Nuclear Wallet Cards, Radioactivity Handbook, and books on neutron cross sections and resonance parameters. In addition, the NNDC maintains three bibliographic files: NSR - for nuclear structure and decay data related references, CINDA - a bibliographic file for neutron induced reactions, and CPBIB - for charged particle reactions. Selected retrievals from evaluated data and bibliographic files are possible on-line or on request from NNDC. 6 refs., 1 fig.

Tuli, J.K.

1985-01-01T23:59:59.000Z

395

Effects of Nanoscale Structure on the Magnetism and Transport Properties of Chromium and Chromium-Aluminum Alloys  

E-Print Network (OSTI)

scattering in the electrical resistivity of Cr thin ?lms.Magnetic susceptibility and electrical resistivity of dilutedependence of the electrical resistivity and resonance

Boekelheide, Zoe Austin

2011-01-01T23:59:59.000Z

396

Fusion Nuclear Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Systems Modeling, Simulation & Validation Nuclear Systems Technology Reactor Technology Nuclear Science Home | Science & Discovery | Nuclear Science | Research...

397

Coherent scattering by a spherical medium of resonant atoms  

Science Conference Proceedings (OSTI)

We consider the problem of coherent resonant scattering of electromagnetic waves by a spherical medium of two-level atoms. The frequency dependence of the scattering amplitudes and cross sections reveals a complex structure of narrow peaks and dips. We relate these scattering resonances to the cooperative emission resonances characteristic of a sphere. We find the scattering to show considerable interference between the electric and magnetic multipole contributions, particularly in the lower multipole orders. This interference tends to enhance anisotropies in the differential scattering cross section even for small spheres. For such spheres, the peak values of the resonant contributions of the low-order multipoles to the total scattering cross section can increase with multipole order, in contrast to the usual decrease seen in nonresonant scattering.

Prasad, Sudhakar; Glauber, Roy J. [Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)

2011-06-15T23:59:59.000Z

398

Nuclear Analytical Chemistry Portal  

Science Conference Proceedings (OSTI)

NIST Home > Nuclear Analytical Chemistry Portal. Nuclear Analytical Chemistry Portal. ... see all Nuclear Analytical Chemistry news ... ...

2010-08-02T23:59:59.000Z

399

Magnetic Storms  

Science Conference Proceedings (OSTI)

... magnetic reversal. As there is no predictive science of geomagnetism, we currently lack even simple forecasts. Our scientific ...

2010-10-05T23:59:59.000Z

400

Magnetic Imaging  

Science Conference Proceedings (OSTI)

... data-storage and permanent magnets with increased energy products, in ... Optimization of future materials, including improved yields, requires an ...

2012-10-02T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Magnetic Properties  

Science Conference Proceedings (OSTI)

...Since the discovery of high-temperature superconductors in 1986 (Ref 10), the demonstration of magnetic flux exclusion

402

Spin-flip induction of Fano resonance upon electron tunneling through atomic-scale spin structures  

Science Conference Proceedings (OSTI)

The inclusion of inelastic spin-dependent electron scatterings by the potential profiles of a single magnetic impurity and a spin dimer is shown to induce resonance features due to the Fano effect in the transport characteristics of such atomic-scale spin structures. The spin-flip processes leading to a configuration interaction of the system's states play a fundamental role for the realization of Fano resonance and antiresonance. It has been established that applying an external magnetic field and a gate electric field allows the conductive properties of spin structures to be changed radically through the Fano resonance mechanism.

Val'kov, V. V., E-mail: vvv@iph.krasn.ru; Aksenov, S. V., E-mail: asv86@iph.krasn.ru [Russian Academy of Sciences, Siberian Branch, Kirensky Institute of Physics (Russian Federation); Ulanov, E. A. [Siberian State Aerospace University (Russian Federation)

2013-05-15T23:59:59.000Z

403

Quartz resonator processing system  

DOE Patents (OSTI)

Disclosed is a single chamber ultra-high vacuum processing system for the oduction of hermetically sealed quartz resonators wherein electrode metallization and sealing are carried out along with cleaning and bake-out without any air exposure between the processing steps. The system includes a common vacuum chamber in which is located a rotatable wheel-like member which is adapted to move a plurality of individual component sets of a flat pack resonator unit past discretely located processing stations in said chamber whereupon electrode deposition takes place followed by the placement of ceramic covers over a frame containing a resonator element and then to a sealing stage where a pair of hydraulic rams including heating elements effect a metallized bonding of the covers to the frame.

Peters, Roswell D. M. (Rustburg, VA)

1983-01-01T23:59:59.000Z

404

Assembly and magnetic properties of nickel nanoparticles on silicon nanowires  

SciTech Connect

The directed assembly of magnetic Ni nanoparticles at the tips of silicon nanowires is reported. Using electrodeposition Ni shells of thickness from 10 to 100 nm were selectively deposited on Au catalytic seeds at the ends of nanowires. Magnetic characterization confirms a low coercivity ({approx}115 Oe) ferromagnetic behavior at 300 K. This approach to multifunctional magnetic-semiconducting nanostructure assembly could be extended to electrodeposition of other materials on the nanowire ends, opening up novel ways of device integration. Such magnetically functionalized nanowires offer a new approach to developing novel highly localized magnetic probes for high resolution magnetic resonance force microscopy.

Picraux, Samuel T [Los Alamos National Laboratory; Manandhar, Pradeep [Los Alamos National Laboratory; Nazaretski, E [Los Alamos National Laboratory; Thompson, J [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

405

Resonant electron-CF collision processes  

SciTech Connect

Electronic structure methods are combined with variationalfixed-nuclei electron scattering calculations and nuclear dynamicsstudies to characterize resonant vibrational excitation and electronattachment processes in collisions between low-energy electrons and CFradicals. Several low-lying negative ion states are found which give riseto strong vibrational excitation and which are expected to dominate thelow-energy electron scattering cross sections. We have also studiedseveral processes which could lead to production of negative ions (F- andC-), However, in contrast to other recent predictions, we do not find CFin itsground state to be a significant source of negative ion productionwhen interacting with thermal electrons.

Trevisan, Cynthia S.; Orel, Ann E.; Rescigno, Thomas N.

2005-03-18T23:59:59.000Z

406

Self-consistent resonance in a plasma  

E-Print Network (OSTI)

As an application of the solution of the equations of electromagnetic self-consistency in a plasma, found in a previous paper, the study of controlled thermo-nuclear fusion is undertaken. This study utilizes the resonance which can be developed in the plasma, as indicated by the above solution, and is based to an analysis of the underlying forced oscillation under friction. As a consequence, we find that, in this way, controlled thermonuclear fusion seems now to be feasible in principle. The treatment is rather elementary, and it may serve as a guide for more detailed calculations.

Evangelos Chaliasos

2005-10-14T23:59:59.000Z

407

Future of Nuclear Data for Nuclear Astrophysics  

Science Conference Proceedings (OSTI)

Nuclear astrophysics is an exciting growth area in nuclear science. Because of the enormous nuclear data needs of this field

Michael S. Smith

2005-01-01T23:59:59.000Z

408

Countering Nuclear Terrorism | National Nuclear Security Administratio...  

NLE Websites -- All DOE Office Websites (Extended Search)

Countering Nuclear Terrorism | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response...

409

Nuclear Detonation Detection | National Nuclear Security Administratio...  

National Nuclear Security Administration (NNSA)

Nuclear Nonproliferation Program Offices > Office of Nonproliferation Research & Development > Nuclear Detonation Detection Nuclear Detonation Detection Develop, Demonstrate, and...

410

Chernobyl Nuclear Accident | National Nuclear Security Administration  

NLE Websites -- All DOE Office Websites (Extended Search)

Chernobyl Nuclear Accident | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response...

411

Ex-Situ High Resolution NMR and MRI - Lawrence Berkeley ...  

Alexander Pines and colleagues have opened the way to high resolution ex situ nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI).

412

1  

NLE Websites -- All DOE Office Websites (Extended Search)

magnetic resonance offers new insights into Pu 239 May 29, 2012 Nuclear magnetic resonance offers new insights into Pu 239 Fingerprint of element found by LANLJapanese team The...

413

RESONANT CAVITY EXCITATION SYSTEM  

DOE Patents (OSTI)

A cavity excitation circuit is described for rapidly building up and maintaining high-level oscillations in a resonant cavity. The circuit overcomes oscillation buildup slowing effects such as ion locking in the cavity by providing for the selective application of an amplified accelerating drive signal to the main cavity exciting oscillator during oscillation buildup and a direct drive signal to the oscillator thereafter.

Baker, W.R.

1959-08-01T23:59:59.000Z

414

Nucleon-nucleon resonances  

SciTech Connect

The experimental techniques related to NN resonance measurements are described. The technique used is the good geometry transmission experiment. The basic idea is to measure the difference in the attenuation factor for the corresponding difference between the total cross sections of N + N interactions for forward and reverse momentum as a function of the solenoid current. 26 references. (JFP)

Auer, I.P.

1979-01-01T23:59:59.000Z

415

Nuclear Science  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Science Science and Engineering Education Sourcebook 2013 American Nuclear Society US Department of Energy Nuclear Science & Engineering Education Sourcebook 2013 North American Edition American Nuclear Society Education, Training, and Workforce Division US Department of Energy Office of Nuclear Energy Editor and Founder John Gilligan Professor of Nuclear Engineering North Carolina State University Version 5.13 Welcome to the 2013 Edition of the Nuclear Science and Engineering Education (NS&EE) Sourcebook. We have evolved and improved! The core mission of the Sourcebook has not changed, however. Our purpose is to facilitate interaction among faculty, students, industry, and government agencies to accomplish nuclear research, teaching and service activities. Since 1986 we have compiled critical information on nuclear

416

Nuclear forces  

Science Conference Proceedings (OSTI)

These lectures present an introduction into the theory of nuclear forces. We focus mainly on the modern approach

2013-01-01T23:59:59.000Z

417

Neutral Pion Electroproduction in the Delta Resonance Region  

Science Conference Proceedings (OSTI)

The electroproduction of baryon resonances at high Q2 is examined. Analysis focuses on the Delta(1232) resonance via exclusive pseudoscalar meson production of 0 particles. Differential cross sections are extracted for exclusive 0 electroproduction. In the central invariant mass (W) region the cross sections are used to extract resonant multipole amplitudes. In particular, the ratio of the electric quadrupole to magnetic dipole amplitudes (E2/M1) will be discussed for the Delta(1232) resonance. The transition to pQCD is discussed in terms of E2/M1 and other multipoles. The helicity amplitude A3/2 can be used as a baryon helicity conservation meter in this context and will be discussed. The fast shrinking of the resonant contribution in the Delta region is observed at this high momentum transfer. Apart from the observables related to pQCD scaling, the transition form factor G#23;M is extracted along with the scalar to magnetic dipole ratio C2/M1.

Anthony Villano

2007-11-01T23:59:59.000Z

418

Nuclear weapons, nuclear effects, nuclear war  

SciTech Connect

This paper provides a brief and mostly non-technical description of the militarily important features of nuclear weapons, of the physical phenomena associated with individual explosions, and of the expected or possible results of the use of many weapons in a nuclear war. Most emphasis is on the effects of so-called ``strategic exchanges.``

Bing, G.F.

1991-08-20T23:59:59.000Z

419

NIST Electron Paramagnetic Resonance Facility  

Science Conference Proceedings (OSTI)

... leading a national and international effort in electron paramagnetic resonance ... centers (molecules or atoms with unpaired electrons) are produced ...

420

Symmetry Energy Constraints from Giant Resonances: A Theoretical Overview  

E-Print Network (OSTI)

Giant resonances encapsulate the dynamic response of the nuclear ground state to external perturbations. As such, they offer a unique view of the nucleus that is often not accessible otherwise. Although interesting in their own right, giant resonances are also enormously valuable in providing stringent constraints on the equation of state of asymmetric matter. We this view in mind, we focus on two modes of excitation that are essential in reaching this goal: the isoscalar giant monopole resonance (GMR) and the isovector giant dipole resonance (GDR). GMR energies in heavy nuclei are sensitive to the symmetry energy because they probe the incompressibility of neutron-rich matter. Unfortunately, access to the symmetry energy is hindered by the relatively low neutron-proton asymmetry of stable nuclei. Thus, the measurement of GMR energies in exotic nuclei is strongly encouraged. In the case of the GDR, we find the electric dipole polarizability of paramount importance. Indeed, the electric dipole polarizability appears as one of two laboratory observables -- with the neutron-skin thickness being the other -- that are highly sensitive to the density dependence of the symmetry energy. Finally, we identify the softness of skin and the nature of the pygmy resonance as important unsolved problems in nuclear structure.

J. Piekarewicz

2013-07-29T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Nuclear Deterrence  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Deterrence Nuclear Deterrence Nuclear Deterrence LANL's mission is to develop and apply science and technology to ensure the safety, security, and effectiveness of the U.S. nuclear deterrent; reduce global threats; and solve other emerging national security and energy challenges. April 12, 2012 A B-2 Spirit bomber refuels from a KC-135 Stratotanker A B-2 Spirit bomber refuels from a KC-135 Stratotanker. Contact Operator Los Alamos National Laboratory (505) 667-5061 Charlie McMillan, Director: "For the last 70 years there has not been a world war, and I have to think that our strong deterrent has something to do with that fact." Mission nuclear weapons Charlie McMillan, Director of Los Alamos National Laboratory 1:06 Director McMillan on nuclear deterrence While the role and prominence of nuclear weapons in U.S. security policy

422

Design and testing of an electron cyclotron resonance heating ion source for use in high field compact superconducting cyclotrons  

E-Print Network (OSTI)

The main goal of this project is to evaluate the feasibility of axial injection of a high brightness beam from an Electron Cyclotron Resonance ion source into a high magnetic field cyclotron. Axial injection from an ion ...

Artz, Mark E

2012-01-01T23:59:59.000Z

423

Magnetic Materials  

Science Conference Proceedings (OSTI)

Oct 27, 2009 ... Extreme magnetic fields (>2 tesla), especially when combined with temperature, are being shown to revolutionize materials processing and...

424

Tandem resonator reflectance modulator  

DOE Patents (OSTI)

A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors. 8 figs.

Fritz, I.J.; Wendt, J.R.

1994-09-06T23:59:59.000Z

425

Tandem resonator reflectance modulator  

DOE Patents (OSTI)

A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors.

Fritz, Ian J. (Albuquerque, NM); Wendt, Joel R. (Albuquerque, NM)

1994-01-01T23:59:59.000Z

426

Iterative quantum state transfer along a chain of nuclear spin qubits  

E-Print Network (OSTI)

Transferring quantum information between two qubits is a basic requirement for many applications in quantum communication and quantum information processing. In the iterative quantum state transfer (IQST) proposed by D. Burgarth et al. [Phys. Rev. A 75, 062327 (2007)], this is achieved by a static spin chain and a sequence of gate operations applied only to the receiving end of the chain. The only requirement on the spin chain is that it transfers a finite part of the input amplitude to the end of the chain, where the gate operations accumulate the information. For an appropriate sequence of evolutions and gate operations, the fidelity of the transfer can asymptotically approach unity. We demonstrate the principle of operation of this transfer scheme by implementing it in a nuclear magnetic resonance quantum information processor.

Jingfu Zhang; Nageswaran Rajendran; Xinhua Peng; Dieter Suter

2007-06-03T23:59:59.000Z

427

Electromagnetic energy within magnetic spheres  

E-Print Network (OSTI)

Consider that an incident plane wave is scattered by a homogeneous and isotropic magnetic sphere of finite radius. We determine, by means of the rigorous Mie theory, an exact expression for the time-averaged electromagnetic energy within this particle. For magnetic scatterers, we find that the value of the average internal energy in the resonance picks is much larger than the one associated with a scatterer with the same nonmagnetic medium properties. This result is valid even, and specially, for low size parameter values. Expressions for the contributions of the radial and angular field components to the internal energy are determined. For the analytical study of the weak absorption regime, we derive an exact expression for the absorption cross section in terms of the magnetic Mie internal coefficients. We stress that although the electromagnetic scattering by particles is a well-documented topic, almost no attention has been devoted to magnetic scatterers. Our aim is to provide some new analytical results, which can be used for magnetic particles, and empha- size the unusual properties of the magnetic scatters, which could be important in some applications.

Tiago Jose Arruda; Alexandre Souto Martinez

2010-10-14T23:59:59.000Z

428

Superconducting Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

Mit Hilfe der Technologie supraleitender Magnete lassen sich in Mit Hilfe der Technologie supraleitender Magnete lassen sich in Ringbeschleunigern höhere Energien erreichen. Weil supraleitende Spulen keinen elektrischen Widerstand aufweisen, können damit stärkere Magnetfelder erzeugt werden. In normal leitenden Elektromagneten wird - wegen des elektrischen Widerstands der Drähte - die Spule aufgeheizt. Auf diese Weise geht sehr viel Energie in Form von Wärme verloren, was die Energiekosten dieser Magnete in die Höhe treibt. Supraleitende Spulen erlauben es, Magnete grosser Feldstärke unter günstigen Bedingungen zu betreiben und damit die Energiekosten zu senken. Durch den Einbau supraleitender Spulen in den Ringbeschleuniger von Fermilab konnte dessen Energie verdoppelt werden.Auch der im Bau befindliche "Large Hadron Collider" am CERN wird supraleitende Magnete

429

Magnetic nanotubes  

DOE Patents (OSTI)

A magnetic nanotube includes bacterial magnetic nanocrystals contacted onto a nanotube which absorbs the nanocrystals. The nanocrystals are contacted on at least one surface of the nanotube. A method of fabricating a magnetic nanotube includes synthesizing the bacterial magnetic nanocrystals, which have an outer layer of proteins. A nanotube provided is capable of absorbing the nanocrystals and contacting the nanotube with the nanocrystals. The nanotube is preferably a peptide bolaamphiphile. A nanotube solution and a nanocrystal solution including a buffer and a concentration of nanocrystals are mixed. The concentration of nanocrystals is optimized, resulting in a nanocrystal to nanotube ratio for which bacterial magnetic nanocrystals are immobilized on at least one surface of the nanotubes. The ratio controls whether the nanocrystals bind only to the interior or to the exterior surfaces of the nanotubes. Uses include cell manipulation and separation, biological assay, enzyme recovery, and biosensors.

Matsui, Hiroshi (Glen Rock, NJ); Matsunaga, Tadashi (Tokyo, JP)

2010-11-16T23:59:59.000Z

430

Nuclear Energy  

Nuclear Energy Environmental Mgmt. Study Objectives: Respond to the pressing need to refine existing corrosion models: Predict performance in wide range of environments

431

Nuclear Reactors  

NLE Websites -- All DOE Office Websites (Extended Search)

Reactors Nuclear reactors created not only large amounts of plutonium needed for the weapons programs, but a variety of other interesting and useful radioisotopes. They produced...

432

Nuclear Astrophysics  

Science Conference Proceedings (OSTI)

I review progress that has been made in nuclear astrophysics over the past few years and summarize some of the questions that remain. Topics selected include solar neutrinos

W. C. Haxton

2006-01-01T23:59:59.000Z

433

Nuclear & Uranium  

U.S. Energy Information Administration (EIA)

Table 17. Purchases of enrichment services by owners and operators of U.S. civilian nuclear power reactors by contract type in delivery year, 2012

434

Nuclear Weapons  

NLE Websites -- All DOE Office Websites (Extended Search)

nuclear science that has had a significant global influence. Following the observation of fission products of uranium by Hahn and Strassmann in 1938, a uranium fission weapon...

435

NUCLEAR ENERGY  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

could improve the economic and safety performance of these advanced reactors. Nuclear power can reduce GHG emissions from electricity production and possibly in co-generation...

436

Generating electron cyclotron resonance plasma using distributed scheme  

Science Conference Proceedings (OSTI)

This study employs a distributed microwave input system and permanent magnets to generate large-area electron cyclotron resonance (ECR) plasma. ECR plasmas were generated with nitrogen gas, and the plasma density was measured by Langmuir probe. A uniform ECR plasma with the electron density fluctuation of {+-}9.8% over 500 mm Multiplication-Sign 500 mm was reported. The proposed idea of generating uniform ECR plasma can be scaled to a much larger area by using n Multiplication-Sign n microwave input array system together with well-designed permanent magnets.

Huang, C. C. [Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan (China); Chung-Shan Institute of Science and Technology, Lung-Tan, Taoyuan, Taiwan (China); Chang, T. H.; Chen, N. C.; Chao, H. W. [Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China); Chen, C. C. [Chung-Shan Institute of Science and Technology, Lung-Tan, Taoyuan, Taiwan (China); Chou, S. F. [Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan (China)

2012-08-06T23:59:59.000Z

437

Nuclear reactor control apparatus  

DOE Patents (OSTI)

Nuclear reactor core safety rod release apparatus comprises a control rod having a detent notch in the form of an annular peripheral recess at its upper end, a control rod support tube for raising and lowering the control rod under normal conditions, latches pivotally mounted on the control support tube with free ends thereof normally disposed in the recess in the control rod, and cam means for pivoting the latches out of the recess in the control rod when a scram condition occurs. One embodiment of the invention comprises an additional magnetically-operated latch for releasing the control rod under two different conditions, one involving seismic shock.

Sridhar, Bettadapur N. (Cupertino, CA)

1983-11-01T23:59:59.000Z

438

Lensless Imaging of Magnetic Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

Lensless Imaging of Magnetic Lensless Imaging of Magnetic Nanostructures Lensless Imaging of Magnetic Nanostructures Print Wednesday, 28 March 2012 00:00 Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging for the first time to nanometer-scale magnetic structures in an alloy. Many Ways To See You open your eyes and detect the light rays streaming through your bedroom window (transmission), illuminating your socks on the floor (scattering). You put on your glasses (refraction) to detect the state of your image in the mirror (reflection). If you are an ALS scientist, perhaps you go to work and shine some x-ray light on a crystal to detect the arrangement of the atoms in the crystal (diffraction). Now, thanks to Turner et al., you can also shine some x-ray light on a magnetic sample to detect the arrangement of its electron spins through a method known as lensless imaging. This last example is an equally valid way to "see," but instead of using windows, lenses, or mirrors to manipulate light and construct an image, mathematical formulas are used to describe the effects that particles and fields in the sample have on the light. These formulas have always contained terms that relate to the electron spin of magnetic atoms, but they were previously ignored. Using the full formula allows for the determination of not only crystal structure, but magnetic spin distribution and orientation as well, with a spatial resolution limited only by the wavelength of x-rays used. This promising method can be used at any coherent light source, including modern x-ray free-electron lasers, where ultrashort pulses would freeze-frame magnetic changes, offering the potential for imaging in unprecedented detail the structure and motion of boundaries between regions with different magnetic orientation.

439

Resonant Soft X-Ray Scattering - Combining Structural with Spectroscopic  

NLE Websites -- All DOE Office Websites (Extended Search)

Resonant Soft X-Ray Scattering - Combining Structural with Spectroscopic Resonant Soft X-Ray Scattering - Combining Structural with Spectroscopic Refinement Friday, September 28, 2012 - 10:00am SLAC, Bldg. 137, Room 322 SSRL Presents Kevin Stone X-ray absorption spectroscopy has become an important tool in understanding the electronic structure of materials. Resonant absorption edges in the soft x-ray regime are especially interesting as they allow the study of the lighter elements, such as in organic or organo-metallic substances, as well as important L-edges of the 3d transition metals important in magnetic and oxide systems. Measurements of soft x-ray absorption spectra are inherently surface sensitive, and are plagued by issues such as extinction (in electron yield measurements) or self absorption (in fluorescence yield

440

Nuclear Forces and Nuclear Systems  

NLE Websites -- All DOE Office Websites (Extended Search)

Forces and Nuclear Systems Forces and Nuclear Systems Our goal is to achieve a description of nuclear systems ranging in size from the deuteron to nuclear matter and neutron stars using a single parameterization of the nuclear forces. Our work includes both the construction of two- and three-nucleon potentials and the development of many-body techniques for computing nuclear properties with these interactions. Detailed quantitative, computationally intense studies are essential parts of this work. In the last decade we have constructed several realistic two- and three-nucleon potential models. The NN potential, Argonne v18, has a dominant charge-independent piece plus additional charge-dependent and charge-symmetry-breaking terms, including a complete electromagnetic interaction. It fits 4301 pp and np elastic scattering data with a chi**2

Note: This page contains sample records for the topic "nuclear magnetic resonance" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Resonance test system  

DOE Patents (OSTI)

An apparatus (10) for applying at least one load to a specimen (12) according to one embodiment of the invention may comprise a mass (18). An actuator (20) mounted to the specimen (12) and operatively associated with the mass (18) moves the mass (18) along a linear displacement path (22) that is perpendicular to a longitudinal axis of the specimen (12). A control system (26) operatively associated with the actuator (20) operates the actuator (20) to reciprocate the mass (18) along the linear displacement path (22) at a reciprocating frequency, the reciprocating frequency being about equal to a resonance frequency of the specimen (12) in a test configuration.

Musial, Walter (Boulder, CO); White, Darris (Superior, CO)

2011-05-31T23:59:59.000Z

442

Quantum search with resonances  

E-Print Network (OSTI)

We present a continuous time quantum search algorithm analogous to Grover's. In particular, the optimal search time for this algorithm is proportional to $\\sqrt{N}$, where $N$ is the database size. This search algorithm can be implemented using any Hamiltonian with a discrete energy spectrum through excitation of resonances between an initial and the searched state. This algorithm is robust and, as in the case of Grover's, it allows for an error $O(1/\\sqrt{N})$ in the determination of the searched state. A discrete time version of this continuous time search algorithm is built, and the connection between the search algorithms with discrete and continuous times is established.

A. Romanelli; A. Auyuanet; R. Donangelo

2005-02-24T23:59:59.000Z

443

Probing Axions with Radiation from Magnetic Stars  

E-Print Network (OSTI)

Recent experiments suggest that polarized photons may couple significantly to pseudoscalar particles such as axions. We study the possible observational signatures of axion-photon coupling for radiation from magnetic stars, with particular focus on neutron stars. We present general methods for calculating the axion-photon conversion probability during propagation through a varying magnetized vacuum as well as across an inhomogeneous atmosphere. Partial axion-photon conversion may take place in the vacuum region outside the neutron star. Strong axion-photon mixing occurs due to a resonance in the atmosphere, and depending on the axion coupling strength and other parameters, significant axion-photon conversion can take place at the resonance. Such conversions may produce observable effects on the radiation spectra and polarization signals from the star. We also apply our results to axion-photon propagation in the Sun and in magnetic white dwarfs. We find that there is no appreciable conversion of solar axions to photons during the propagation.

Dong Lai; Jeremy Heyl

2006-09-28T23:59:59.000Z

444

Nuclear Weapons Journal Archive  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Weapons Journal Archive Nuclear Weapons Journal The Nuclear Weapons Journal ceased publication after Issue 2, 2009. Below are Nuclear Weapons Journal archived issues. Issue...

445

Nonreactor Nuclear Facilities Division  

NLE Websites -- All DOE Office Websites (Extended Search)

role in developing science and technology for nuclear power programs, nuclear propulsion, nuclear medicine, and the nation's nuclear weapon program among others. Many...

446

Experimental Observation of Nuclear Reactions in Palladium and Uranium  

Science Conference Proceedings (OSTI)

By submitting various metals (Pd, U) containing hydrogen (from 2000 to 700 000 atoms of hydrogen for 1 000 000 atoms of the host metal) to the combined action of electrical currents and magnetic fields, we have observed a sizeable exothermal effect (from 0.1 to 8 W for 500 mg of metal used). This effect is beyond experimental errors, the energy output being typically 130 to 250{percent} of the energy input and not of chemical origin (exothermal effect in the range of 7000 MJ/mol of metal in the case of palladium and of 60 MJ/mol in the case of uranium). New chemical species also appear in the processes metals. It has been shown by a QED calculation that resonances of long lifetime (s), nuclear dimensions (fm), and low energy of formation (eV) could exist. This concept seems to look like the 'shrunken hydrogen atoms' proposed by various authors. It is indeed very different in two ways (a) being a metastable state, it needs energy to be formed (a few eV) and reverts to normal hydrogen after a few seconds, liberating back its energy of formation (it is thus not the source of the energy observed); (b) its formation can be described as the electron spin/proton nuclear spin interaction becoming first order in the lattice environment (whereas it is third order in a normal hydrogen atom). Moreover, we consider that the hydrex cannot yield a neutron because this reaction is strongly endothermic. To explain our results, we put forward the following working hypothesis: In a metal lattice and under proper conditions, the formation of such resonances (metastable state) could be favored. We propose to call them HYDREX, and we assume that they are actually formed in cold fusion (CF) and low-energy nuclear reaction (LENR) experiments. Once formed, a number of HYDREX could gather around a nucleus of the lattice to form a cluster of nuclear size and of very long life time compared to nuclear time (10{sup -22} s). In this cluster, nuclear rearrangements could take place, yielding mainly {sup 4}He, nuclei of atomic masses smaller than that of the host metal and small amounts of {sup 3}He and tritium. Because this nuclear rearrangement is a many-body reaction, the products formed should be stable products in their ground states, most of the reaction energy being carried away as kinetic energy by the alpha particles formed. The HYDREX hypothesis describes CF and LENR as fundamentally the same phenomenon, which we propose to call NUCLEAR CATALYSIS. Depending on the conditions of a CF or LENR experiment, the products formed may look very different, but the initial step is always the synthesis of HYDREX. When this synthesis is mastered, CF and LENR experiments should become fully reproducible.

J. Dufour; D. M