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Code: PG	Time Slot/Poster Number: 105	Session: Instrumentation, Poster
Easy Shimming with Orthogonalized Shims
Carl A. Michal
University of British Columbia, Vancouver, Canada
Abstract
A new approach to optimizing shim currents for magnetic resonance magnets is presented. This approach orthogonalizes the shim gradients to allow a simple one-dimensional optimization for each orthogonalized "composite shim." The technique demands no specialized equipment, requiring only the acquisition of simple one-dimensional spectra. Examples from high-resolution NMR spectrometers are presented, including one system with a cryoprobe and 39 shim coils. The settings found with the new algorithm provide higher resolution than was obtained by the spectrometer vendor's installation engineers using field-mapping and gradient shimming techniques. The examples shown demonstrate the advantages of the technique for high-resolution NMR, but we expect the approach will also find application in a broad variety of areas including imaging and in vivo spectroscopy.

Code: PG	Time Slot/Poster Number: 106	Session: Instrumentation, Poster
In-situ NMR of Polymers under mechanical stress
Ute Böhme¹; Bo Xu²; Johannes Leisen²; Haskell W Beckham²; Ulrich Scheler¹
¹Leibniz Institute of Polymer Research Dresden, Dresden, Germany; ²Georgia Institute of Technology, Atlanta, Georgia
Abstract
The change of molecular order and dynamics of macromolecules undermechanical stress has been studied in situ by low-field NMR. A permanent magnet based on a Halbach arrangement is placed in a stretching apparatus, because of the limited stray field the spectrum is not affected by the surrounding equipment. Stretching of eleastomers results in reduction of T2 which results from stronger residual dipolar couplings. In semicrystalline polymers significant shortening of T2 is found as a result of the stretching. Subsequent partial relaxation of the shortened T2 is followed in situ.

Code: PG	Time Slot/Poster Number: 107	Session: Instrumentation, Poster
A Digital NMR Spectrometer Based on Distributed Network Architecture
Qingjia Bao
Wuhan Institute of Physics and Mathematics, Wuhan, China
Abstract
We have developed a NMR spectrometer based on distributed network architecture. In this spectrometer system, key components, such as transmitters and receivers, no longer need a master computer to control and synchronize ,but are independent of each other and controlled by their own pulse programmers. Owing to this architecture design, the entire spectrometer system has a very good scalability, and because of less communication among the various components, the hardware backplane design will be straightforward. At the same time, the entire system synchronization will be very precise. In order to support the spectrometer hardware, we have developed entire software including spectrometer control, data process and graphical pulse sequence programming environment. Finally, we performed a variety of experiments，and get satisfactory results.

Code: PG	Time Slot/Poster Number: 108	Session: Instrumentation, Poster
Very Fast Magic Angle Spinning up to 80 kHz
Yuki Endo¹; Yusuke Nishiyama¹; Kazuo Yamauchi²; Katsuya Hioka¹; Tetsuo Asakura²
¹JEOL Ltd., Tokyo, Japan; ²Tokyo University of Agriculture and Technology, Tokyo, Japan
Abstract
A brand new magic angle spinning (MAS) module with a sample tube diameter of 1mm is developed. A stable sample spinning up to 80 kHz is achieved. The active sample volume is 0.5 uL. The module will open a new filed of solid-state NMR. The applications to NMR probe will be discussed at the presentation with various NMR spectra.

Code: PG	Time Slot/Poster Number: 109	Session: Instrumentation, Poster
Recovery of Noise-Corrupted NMR Data acquired and accumulated in unstable Magnetic Field
Gianni Ferrante¹; Giuseppe Martini²
¹Stelar s.r.l., Mede (Pv) , Italy; ²University of Pavia, Electronic department, Pavia, Italy
Abstract
The acquisition of NMR signals in unstable magnetic fields do not allow the in-phase and in-quadrature signal accumulation to improve SNR. On the contrary the modulus S is not affected by B0 field instability and can be accumulated. Nevertheless this operation introduces an error called ‘noise bias’ due to the rectification of noise. Aim of work presented in this poster is to test the applicability and the effectiveness of the correction method applied to real NMR data acquired in unstable field for the estimation of T1 and T2. Results of measurements done both in stable and unstable field demonstrate that the modulus of an NMR signal can be cumulated, corrected and used for the estimation of relaxation times.

Code: PG	Time Slot/Poster Number: 110	Session: Instrumentation, Poster
A Novel 9.4 T Double Tuned Microstrip Surface TEM Resonator for 1H/23Na
Mattia Polsoni¹; Assunta Vitacolonna¹; Antonello Sotgiu^{1, 2}; Jon N Shah^{3, 4}; Marcello Alecci¹
¹Dip SDS, University of L'Aquila, L'Aquila, Italy; ²ITA srl, L'Aquila, Italy; ³Inst of Neuroscience and Medicine, Research Centre, Juelich, Germany; ⁴Faculty of Medicine, Dep of Neurology, RWTH, Aachen University, Germany
Abstract
In this work we describe a novel 9.4 T DT microstrip surface TEM prototype suitable for 23Na-1H. It is composed by two external elements for the sodium channel and one central elements for the proton channel. To chose the best geometrical design, we realized a study of the frequency sweep vs the two external elements distance with and without the presence of the central 1H element. We also present the workbench testing of the final 9.4T DT microstrip surface TEM prototype tuned at 105.8 MHz (23Na channel) and 400.4 MHz (1H channel).

Code: PG	Time Slot/Poster Number: 111	Session: Instrumentation, Poster
Multiplexing the NMR Probe: CapNMR with a Dual FlowCell Probe and an Automated System Perspective
James Norcross; Craig Milling; Robert Albrecht; Steve Xu; Dean Olson; Tim Peck
Protasis Corporation, Savoy, IL
Abstract
Each NMR flow cell in the Dual FlowCell (DFC) probe delivers the same spectral resolution and S/N as in a single-flowcell CapNMR probe, but overall capacity doubles. Both rf microcoils are simultaneously shimmed to high resolution for parallel data acquisition. Alternatively, individual shim settings are readily set to enable serial operation such as for different solvents. To complement this probe design, One-Minute NMR automation is enhanced to accommodate simultaneous entry of two samples using a single autosampler with two independent, parallel flowpaths each leading to a dedicated flowcell in the DFC probe. An overview of the dual flowcell probe and multiplexed NMR system, including capabilities for enhanced automation, data sets, and applications are described as deployed in a pharmaceutical lab.

Code: PG	Time Slot/Poster Number: 112	Session: Instrumentation, Poster
Tissue equivalent phantoms for 900MHz MRI systems
David M. Peterson
University of Florida, McKnight Brain Institute, Gainesville, FL
Abstract
This work summarizes phantom development that is applicable to ultra high field MRI systems such as the 21T MRI system located at the National High Magnetic Field Laboratory located in Tallahasse, FL. This work describes the methods for building suitable phantoms to engage in RF coil design for these MRI systems.

Code: PG	Time Slot/Poster Number: 113	Session: Instrumentation, Poster
Implementation and Testing of a Portable Earth’s Field MRI System
David Hormuth; Huihui Xu
Rose-Hulman Institute of Technology, Terre Haute, IN
Abstract
This abstract presents the procedures to set up a MRI teaching and research system that uses the Earth's magnetic field (Terranova-MRI) at Rose-Hulman Institute of Technology. Preliminary studies were implemented using standard FID and spin echo imaging sequences on a 2-tube phantom and a kiwi. Results indicate Terranova-MRI provides a practical and in-expensive manner to demonstrate the imaging principles of MRI inside a laboratory and/or other non-idealized environments.

Code: PG	Time Slot/Poster Number: 114	Session: Instrumentation, Poster
A Single-board NMR Spectrometer: Based on Software Defined Radio Architecture
Weinan Tang; Xianchai Lin; Weimin Wang
Institute of Quantum Electronics/Peking University, Beijing, China
Abstract
A single-board software-defined radio spectrometer for NMR is presented. By combining a FPGA and DSP controller with RF front-end circuits, the compact and reconfigurable SDR-based architecture allows described spectrometer with more flexible implementation in software solution and easier adaption to emerging application requirements. The DSP, working as a pulse programmer, communicates to a personal computer via a USB interface and configures FPGA through a parallel port. The FPGA performs digital processing of direct digital synthesizer, digital down converter and gradient waveform generator. The spectrometer operates up to Nyquist frequency (30MHz) under direct sampling and higher frequency with undersampling, allowing gain of receiver and transmitter being digitally controlled. The device has been validated successfully and is suitable for portable NMR systems.

Code: PG	Time Slot/Poster Number: 115	Session: Instrumentation, Poster
Solid-state NMR probes for the study of membrane proteins in hydrated phospholipid bilayers.
Christopher V. Grant; Chin Wu; Stanley Opella
University of California San Diego, La Jolla, CA
Abstract
Solid-state NMR probes developed for static aligned samples of proteins in hydrated phospholipid bilayers will be presented. Further development is essential because the lossy characteristics of these samples adversely impact the performance of the NMR probes, particularly at high frequencies. Double and triple resonance probes that incorporate two technologies will be described. The first uses a Modified Alderman-Grant Coil (MAGC) as the proton resonator in a cross coil configuration. The low inductance MAGC coil leads to a significant reduction in sample heating and a high inductance low frequency coil provides good sensitivity. The second technology is a Strip-Shield probe, in which a Faraday shield is used to reduce sample heating and improve the properties of solenoid coils.

Code: PG	Time Slot/Poster Number: 116	Session: Instrumentation, Poster
Efficient triple-resonant 1H/X/Y low-E MAS probe for biological applications
Peter L. Gor'kov¹; Ivan Hung¹; Chunqi Qian¹; Jason A. Kitchen¹; Guangjin Hou²; Yun Han²; Tatyana Polenova²; William W. Brey¹; Zhehong Gan¹
¹National High Magnetic Field Laboratory, Tallahassee, FL; ²Chemistry and Biochemistry, University of Delaware, Newark, DE
Abstract
To increase sensitivity for concentration-limited samples in solid-state MAS probes one may consider increasing the sample volume by using a rotor of larger diameter. Unfortunately, switching to a larger rotor size may weaken the applied B1 fields, slow the spinning rate, and worsen the frictional heating. To avoid drawbacks associated with larger rotor diameters, we propose to increase sensitivity by extending the coil, sample, and B1 homogeneity region along the spinning axis instead, with the help of custom-modified spinner. We will present an efficient 3.2-mm 1H/13C/15N triple-resonance MAS probe for studies of dilute protein systems at 600 MHz and discuss the strategies used to enhancing its performance at 13C or 15N frequencies, including electrical balancing of all 3 channels.

Code: PG	Time Slot/Poster Number: 117	Session: Instrumentation, Poster
A simulation based study of the effect of pulse errors on spin I=1 double quantum filtered NMR spectroscopy
Cheng Sun; Gregory Boutis
Brooklyn College of The City University of New Yor, Brooklyn , NY
Abstract
Deuterium double quantum filtered (DQF) NMR spectroscopy is a well-known experimental scheme for characterizing anisotropic motion of nuclear spins resulting from local ordering. The method has been implemented with great success in a variety of paradigms to probe structure in biological systems. In this work we investigate the dependence of the double quantum filtered (DQF) NMR pulse sequence on various experimental artifacts such as the magnetic field homogeneity, RF transients pulse, phase errors, finite pulse width effects and pulse flip errors. The simulation results show how various parameters result in artifacts in the DQF spectra, as well as a reduction in signal intensity.

Code: PG	Time Slot/Poster Number: 118	Session: Instrumentation, Poster
Faraday Coils vs. SQUIDs for Liquids Identification Using Ultra-Low Field Nuclear Magnetic Resonance Technique
Andrei Matlashov; Michelle Espy; John Gomez; Robert Kraus; Per Magnelind; Shaun Newman; Henrik Sandin; Igor Savukov; Larry Schultz; Robert Sedillo; Al Urbaitis; Petr Volegov
Los Alamos National Laboratory, Los Alamos, NM
Abstract
Recently it has become possible to perform NMR and MRI in ultra-low field regime that requires measurement field strengths only of the order of 1 Gauss. These techniques exploit the advantages offered by superconducting quantum interference devices or SQUIDs. We have built SQUID based MRI systems for brain imaging and for liquid explosives detection at airports security checkpoints. The requirement for liquid helium cooling limits potential applications for liquid identification. Our experimental comparative investigation shows that room temperature inductive magnetometers provide enough sensitivity in the 3-10 kHz range and can be used for fast liquid explosives detection. We describe an experimental comparison of SQUID based and Faraday coils based instruments that are capable of performing ULF MRI for liquids identification.

Code: PG	Time Slot/Poster Number: 119	Session: Instrumentation, Poster
Modifications for Controlling Output of Automated NMR Systems
Anitha Shankara Linge Gowda; W. John Layton; Folami T. Lapido; Anne-Frances Miller
University of Kentucky, Lexington, KY
Abstract
A series of macros and protocols are being developed to permit automated characterization of numerous samples without user intervention. The physical handling, loading and data collection on large numbers of NMR samples has been automated by robots, in principle permitting the incorporation of NMR experiments in large laboratory courses, and drug development protocols. In practice however, it can be more difficult to obtain useful information from the spectra, such as peak areas and peak frequency lists, in an automated situation where the default parameters are set by a series of macros that may not give satisfactory output. We have been working on a set of macros intended to permit a user to choose criteria for peak selection such as signal-to-noise, which will then guide instrument software in identification of features in the data and result in reliable and useful reports of the important features of spectra. The goal is for the instrument to produce useful annotated spectra for different samples, without a user needing to modify detection thresholds or peak separations on a spectrum-to-spectrum basis. Thus, even end-users with little familiarity with NMR spectra can make use of the output. Examples will be presented in the use of these techniques in an automated undergraduate teaching laboratory.

Code: PG	Time Slot/Poster Number: 120	Session: Instrumentation, Poster
Total compensation of pulse transients inside a resonator
Yutaka Tabuchi¹; Makoto Negoro¹; Kazuyuki Takeda²; Masahiro Kitagawa¹
¹Graduate School of Engineering Science, Osaka Univ, Toyonaka, Japan; ²Graduate School of Science, Kyoto Univ, Kyoto, Japan
Abstract
A way to suppress the phase transients in magnetic resonance experiment is proposed. It is based on measured response function from the excitation voltage to the RF magnetic field inside the resonator, which includes transmission lines, filters, amplifiers, as well as a resonator. A method to build the excitation voltage which produces the RF magnetic field with intended amplitude and phase inside the resonator is derived. Accurate RF pulsing based on our method is experimentally demonstrated and prospect for coping with the receiver dead-time is also discussed.

Code: PG	Time Slot/Poster Number: 121	Session: Instrumentation, Poster
MR Microimaging with a Cylindrical Ceramic Dielectric Resonator at 21.1 T
Kristina Haines¹; Jose A. Muniz^{2, 3}; Ihssan S. Masad^{2, 3}; Elena Semouchkina¹; Michael Lanagan¹; Andrew Webb^{1, 4}; Samuel Grant^{2, 3}
¹Pennsylvania State University, University Park, PA; ²Florida State University, Tallahassee, FL; ³National High Magnetic Field Laboratory, Tallahassee, FL; ⁴Leiden University Medical Center, Leiden, The Netherlands
Abstract
Previous work with dielectric resonators have shown relatively high Q values, good B1 homogeneity, and increases in SNR in both EPR and MRI. In this study, a cylindrical ceramic (CaTiO3) dielectric resonator design with high relative permittivity and low loss characteristics is evaluated at 21.1 T for MR microimaging. Evaluations (Q values, flip angle maps and SNR) were performed alongside Alderman-Grant and loop gap coil configurations for comparison purposes. Imaging also was performed on an excised rat soleus muscle and mouse spinal cord to demonstrate and validate the capabilities of the dielectric resonator for high resolution imaging.

Code: PG	Time Slot/Poster Number: 122	Session: Instrumentation, Poster
Field stabilization of high field superconducting magnets for solid-state NMR by active shimming
Hideyuki Shinagawa; Shinobu Ohki; Teruaki Fujito; Tadashi Shimizu
National Institute for Materials Science (NIMS), Tsukuba, Japan
Abstract
The field distortion induced by the shimming, through a coupling of the shim-coils and the magnet, were investigated for a high magnetic field superconducting magnet (1H-930 MHz) for high-resolution solid-state nuclear magnetic resonance (NMR). We found the field distortions or field drifts were caused by the shimming, which were not negligible to obtain high-resolution spectra, particularly in the case when the shim setting was largely changed. The amount of the distortion sometimes would be more than 1 ppm and it would last for several days with a time constant about one week. We developed the method to computationally compensate such a distortion, in which the shim-coils are actively controlled with the record of all shim settings that were previously made.

Code: PG	Time Slot/Poster Number: 123	Session: Instrumentation, Poster
A Real-Time Motion Correction Strategy for Echo-Planar Imaging Sequences
Melvyn B. Ooi¹; Sascha Krueger²; William J. Thomas¹; Truman R. Brown¹
¹Columbia University, New York, NY; ²Philips Research Europe, Hamburg, Germany
Abstract
Head motion is a fundamental problem in functional MRI. A prospective, slice-by-slice compensation strategy for rigid-body motion is presented for echo-planar imaging (EPI) sequences. Before the acquisition of each EPI-slice, a short tracking pulse-sequence is used to measure the positions of three micro RF-coil "active markers" integrated into a headband worn by the subject. During head motion, the rigid-body transformation that realigns these markers to their initial positions is fed back to update the image-plane – maintaining it at a fixed orientation relative to the head – before the next EPI-slice is acquired. EPI time-series acquired on a volunteer during a "head-nodding" through-plane motion demonstrates the advantages of real-time motion correction over conventional retrospective image realignment algorithms.