Report No xxxx - Instytut Fizyki JÄdrowej PAN

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The method was experimentally verified with clay specimen on 200 MHz MR tomograph in ISI AS Brno. Reference substance giving the MR signal was water (χ H2O = -9.04·10 -6 ) filled into cube vessel. The field echo method with echotime T E = 5.56 ms [3] was used to acquire MR image with contrast corresponding to the magnetic field inhomogeneity. Experiment was treated one time with clay specimen of 7 mm thickness (Fig. 3A) and next only with water reference (Fig. 3B); basic field has magnetic induction B 0 = 4.7 T. Position of the specimen is depicted in Fig. 3A. Obtained image with phasecontrast was processed in Matlab. After de-noising by the limitation of signal the spatial deformation evoked by magnetic field inhomogeneity in specimen vicinity was eliminated. Acquired phase images were consequently subtracted to eliminate inhomogeneity of the basic field - Fig. 3C. By properly selected slice of this image we have the curve of phase change ∆Θ of the water MR signal in the specimen vicinity, Fig. 3D. For the used MR technique the phase change ∆Θ = 2π rad response to magnetic induction change ∆Θ , where γ is B 0 ∆ = γ ⋅T E gyromagnetic ratio of water. In this way we can identify the course of magnetic induction change in water nearby the clay specimen. Fig. 3. Images obtain from MR experiment with 7 mm thick clay specimen placed on water filled vessel 40×35 mm. Processed in Matlab. From known thickness x 0 of the specimen and measured area ∆B 0 from, the susceptibility of clay specimen was finally calculated B B − ∆B0 ⋅dx -6 S − 0 ∫ 2. 656⋅10 χS = = = = 8.07 ⋅10 -3 B B ⋅∆x 4.7 ⋅7 ⋅10 0 0 Conclusion: The method designed for magnetic susceptibility measurement based on MRI tomography techniques is simple and enables to determine the magnetic susceptibility of such materials, which give no MR signal. After an optimization this method can be used for investigation of the materials used in MR tomography as well as of biological tissues affecting quality of MR images. The paper was prepared within the framework of N°IAA2065201 project of the Grant Agency of the Academy of Sciences of the Czech Republic and with the support of the grant agency of Czech Republic 103/03/Z048. [1] Starčuk jr., Z.: NMR-compatibility of the dental alloy, ISI AS CR, Brno 2003 [2] Zeman, V.: Magnetic susceptibility measurement by NMR. Tesla Brno, 1981 [3] Blumlich B.: NMR Imaging of Materials. Clarenton Press, Oxford, 2000 -5 . 80
A NOVEL SOURCE OF MAGNETIC FIELD FOR IMAGING LASER-POLARIZED 3 HE Katarzyna Suchanek, Mateusz Suchanek, Katarzyna Cieślar, Tadeusz Pałasz, Zbigniew Olejniczak*, Tomasz Dohnalik Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland; *Henryk Niewodniczański Institute of Nuclear Physics, Kraków, Poland The development of the system for NMR imaging of the laser-polarized helium-3 is presented. The source of magnetic field is a permanent Nd-Fe-B magnet characterized by high saturation induction. Since the magnetic field exhibits a large temperature coefficient, the magnet is placed in an air-conditioned Faraday cage, in which the temperature is stabilized with accuracy of +/- 0.1 °C. A 10 cm diameter sphere is a suitable working volume for imaging small animal lungs. A specially designed positioning device was used to precisely measure the magnetic field map on a sphere of radius 5 cm. The initial inhomogeneity of the magnetic field was 361 ppm within the sphere. In order to obtain good quality images, it was necessary to reduce this inhomogeneity by an order of magnitude. The method of improving the homogeneity relies on placing precisely distributed pieces of steel on the poles of the magnet (passive shimming).Using this method a homogeneity of 56 ppm within the sphere was achieved. A system of actively shielded gradient coils mounted between the poles is used for spatial encoding of the NMR signal. The linearity and efficiency of the gradient coils were tested. In addition, the magnitude and the time constant of the eddy currents generated in the magnet poles was estimated. 81
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The Henryk Niewodniczański INSTITU
Page 3 and 4:
Contents R. Banyś, A. Słowik, M.
Page 5 and 6:
J. Kolmas, M. Uniczko, E. Kalinowsk
Page 7 and 8:
Ł. Popenda, Z. Gdaniec, G. Dominia
Page 9 and 10:
USEFULNESS OF PROTON MAGNETIC RESON
Page 11 and 12:
INFLUENCE OF PARAMAGNETIC IONS ON F
Page 13 and 14:
NMR RELAXATION OF PAPER SAMPLES Bar
Page 15 and 16:
SPIN-LATTICE RELAXATION OF D 2 QUAN
Page 17 and 18:
INVESTIGATION OF NEUROPROTECTING EF
Page 19 and 20:
OPTICAL PUMPING OF 3 He Katarzyna C
Page 21 and 22:
NMR STUDY OF GELATION PROCESS OF LO
Page 23 and 24:
MRI INVESTIGATIONS OF HYDROGEL FORM
Page 25 and 26:
CHEMICAL SHIFT TITRATION AT THE INT
Page 27 and 28:
LOCAL DYNAMICS AND ORGANIZATION OF
Page 29 and 30: 1 H NMR DETECTION OF σ-ADDUCTS IN
Page 31 and 32: HYDRATION OF WHEAT PHOTOSYNTHETIC M
Page 33 and 34: References: 1. H. Harańczyk On wat
Page 35 and 36: (EDV) and end-systolic (ESV) volume
Page 37 and 38: THE MOST STABLE POLYMORPHIC FORM OF
Page 39 and 40: A DETERMINATION OF ABSOLUTE SHIELDI
Page 41 and 42: DIAGNOTIC VALUE OF MRI IN CONVERSIO
Page 43 and 44: NMR AND FTIR STUDY OF MOLECULAR DYN
Page 45 and 46: EFFECTS OF INTERMOLECULAR INTERACTI
Page 47 and 48: 600000 Integral of 1D MRI profils [
Page 49 and 50: simultaneous analyse of the tempera
Page 51 and 52: 1 H NMR STUDIES OF PLATINUM(II) CHL
Page 53 and 54: 35 Cl-NQR STUDY OF ELECTRONIC STRUC
Page 55 and 56: 35 Cl- NQR AND 1 H-NMR STUDY OF MOL
Page 57 and 58: THE SYNTHESIS AND NMR ANALYSIS OF T
Page 59 and 60: STUDY OF MOTIONAL PROCESSES OF DRAW
Page 61 and 62: intensity (arb. units) 0,20 0,15 0,
Page 63 and 64: data for Cβ-nonplanar model 3 are
Page 65 and 66: T 1 DISPERSION AND SELF-DIFFUSION N
Page 67 and 68: A LOW FIELD MRI SYSTEM FOR HYPERPOL
Page 69 and 70: 1 H MAS NMR OF FLAVONOIDS Katarzyna
Page 71 and 72: EFFECT OF TEMPERATURE ON LIPOSOME S
Page 73 and 74: 1 H, 13 C NMR AND GIAO/DFT CALCULAT
Page 75 and 76: NMR STUDY OF THE HUMIC ACIDS EXTRAC
Page 77 and 78: NMR STUDY OF LAYERED ANGANITE La 1.
Page 79: MAGNETIC SUSCEPTIBILITY EVALUATION
Page 83 and 84: DETERMINATION OF AMINO ACIDS IN BOD
Page 85 and 86: MOLECULAR DYNAMICS OF TERT-BUTYL CH
Page 87 and 88: MR MICROSCOPY IN COMPARISON OF YOUN
Page 89 and 90: NH CH CH 2 NH CH CO COONa n CH 2 m
Page 91 and 92: 35 Cl-NQR STUDY OF MOLECULAR DYNAMI
Page 93 and 94: 35 Cl-NQR STUDY OF THE SUBSTITUENT
Page 95 and 96: 13 C AND 1 H NUCLEAR MAGNETIC SHIEL
Page 97 and 98: 13 C CPMAS NMR OF ANTHOCYANINS AND
Page 99 and 100: INVESTIGATION OF TRANSESTERIFICATIO
Page 101 and 102: T 2 RELAXATION MAP OF ARTICULAR CAR
Page 103 and 104: MICROTOMOGRAPHY STUDIES OF TABLETS
Page 105 and 106: MAPPING OF THE BI-EXPONENTIAL DIFFU
Page 107 and 108: DEUTERIUM NMR IN RMn 2 D 2 (R = Y,
Page 109 and 110: The neutron scattering (IINS, QNS,
Page 111 and 112: STRUCTURE OF 4-QUINOLINONES ANALYSE
Page 113: NMR MULTIPOLE RELAXATION IN THE ROT
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