Magnetic resonance imaging Nuclear

Nuclear Magnetic Resonance, Volume 31 The Royal Society of Chemistry, 2002 

The major hypotheses that have been proposed to explain the patterns of decay development and its restriction in the wood (xylem) of living trees are outlined briefly. Furthermore, the current understanding of the biochemical and physiological events that contribute to the protection of pre-existing functional sapwood was reviewed with particular reference to the formation of reaction zones at the host-pathogen interface in Acer species, especially the European sycamore maple Acer pseudoplatanus). 

Principles and Characteristics Conventional NMR spectroscopy, in which the resonance frequency of a nucleus is linearly dependent upon the strength of the static magnetic field, can be 

NMR microscopy is limited to nuclei with a favourable sensitivity, intrinsic line width due to T2 relaxation and repetition time allowed by spin-lattice relaxation (mainly H, Li, N, F, Na, Si and P). The nucleus imaged most often is the proton. Reasons are the sensitivity and the weak dipolar couplings between protons in a chemical group 

In NMR spectroscopy, nuclear spins precess about the static magnetic field, Bq, at the Larmor frequency, uo. as given in eq. (5.5), where y is the gyromagnetic ratio  

By tailoring the frequency content of the rf pulse, it is possible to cause only those nuclei within a defined slice of the sample to come into resonance. For imaging in the x-y plane within this slice, a second static field gradient is imposed along the x-axis different positions along the x-axis will experience different fields, and resonate at different frequencies. The y-axis can be added with a third field gradient. The resonance frequency is determined by the local field which varies from point to point. Following perturbation by a rf pulse the return of the spin system to equilibrium is characterised by spin-lattice 

NMR usually assumes that the nuclear spins precess at the same frequency neglecting chemical shift differences arising from different chemical types of 

A laboratory student was converting cyclohexanol to cyclohexyl bromide by using one equivalent of sodium bromide in a large excess of concentrated sulfuric acid. The major product she recovered was not cyclohexyl bromide, but a compound of formula QH q that gave the following C NMR spectrum  

The signal of phosphates in cells and tissues can be followed by NMR spectroscopy. This technique has been used to study the effects of exercise and oxygen starvation on the metabolism of phosphate esters such as ATP. 

Medical NMR imaging is commonly called magnetic resonance imt i (MRI) to avoid the common fear of the word nuclear and the misconception that nuclear means radioactive. There is nothing radioactive about an NMR spectrometer. In fact, MRI is the least invasive, least hazardous method available for imaging the interior of the body. The only common side effect is claustrophobia from being confined within the ring of the wide-bore magnet. 

1 Summary of the Information Provided by Each Type of Spectro i upy  

usually provides helpful informatiotL S, sometimes provides helpf ul information. 

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Morris P G 1986 Nuclear Magnetic Resonance Imaging in Medicine and Biology (Oxford Ciarendon)... 

Ahn C B and Cho Z H 1989 A generalized formulation of diffusion effects in pm resolution nuclear magnetic-resonance imaging Med. Rhys. 16 22-8... 

Balcom, B Fischer, A Carpenter, T Hall, L, Diffusion in Aqueous Gels. Mutual Diffusion Coefficients Measured by One-Dimensional Nuclear Magnetic Resonance Imaging, Journal of the American Chemical Society 115, 3300, 1993. 

L. F. Gladden, P. Alexander 1996, (Applications of nuclear magnetic resonance imaging in process engineering), Meas. Sci. Technol. 7, 423-435. 

W. A. Ellingson, J. L. Ackerman, L. Garrido, J. D. Weyand, R. A. Dimilia 1987, (Characterization of porosity in green-state and partially densified AI2O3 by nuclear magnetic resonance imaging), Ceram. Eng. Sci. Proc. 8, 503—512. 

S. D. Beyea, A. Caprihan, S. J. Glass, A. DiGiovanni 2003, (Non-destructive characterization of nanopore microstructure spatially resolved BET isotherms using nuclear magnetic resonance imaging),/. Appl. Phys. 94 (2), 935—41. 

P. T. Callaghan, Y. Xia 2004, (Nuclear magnetic resonance imaging and veloc-imetry of Fano flow),/. Phys. Condens. Matter 16, 4177- 1192. 

Use of nuclear magnetic resonance imaging as a viscometer for process monitoring), Chem. Eng. Sd. 52, 2049. 

M. A. d Avila, N. C. Shapley, J. H. Walton, S. R. Dungan, R. J. Phillips, R. L. Powell 2003, (Mixing of concentrated emulsions measured by nuclear magnetic resonance imaging), Phys. Fluids 15, 2499. 

A. G., Goloshevsky, J. H. Walton, M. V. Shutov, J. S. de Ropp, S. D. Collins, M. J. McCarthy 2005, (Nuclear magnetic resonance imaging for viscosity measurements of non-Newtonian fluids using a miniaturized rf coil), Meas. Sci. Technol. 16, 513-518. 

Nuclear Magnetic Resonance Imaging in Chemical Engineering... 

NMRI Nuclear magnetic resonance imaging PDA Photodiode array (detection)... 

Nuclear magnetic resonance imaging and electron spin... 

Duce, S.L. and Hall, L.D. 1995. Visualisation of the hydration of food by nuclear magnetic resonance imaging. J. Food Engin. 26, 251-257. 

Gadolinium-dendrimer conjugates have been used as blood pool contrast agents in vivo for nuclear magnetic resonance imaging (MRI) of tumors [65]. The efficacy of the conjugates in such applications is dependent on their biodistribution properties, and these properties vary as a function of dendrimer molecular weight and chemical composition [50]. Dendrimer architecture and synthesis... 

Y. Xu, P. Tang, W.G. Zhang, L. Firestone, P.M. Winter, F-19 nuclear-magnetic-resonance imaging and spectroscopy of sevoflurane uptake, distribution, and elimination in rat-brain. Anesthesiology 83 (1995) 766-774. 

A good (70%) prediction of sensory texture attributes of cooked potatoes has been obtained with nuclear magnetic resonance imaging, however, not all sensory attributes of texture are... 

Abbreviations. NMRI, nuclear magnetic resonance imaging Antp, antennapedia RES, reticuloendothelial system ADEPT, antibody-directed enzyme prodrug therapy TAT. 

Magin, R. et al. (Editors) Biological Effects and Safety Aspects of Nuclear Magnetic Resonance Imaging and Spectroscopy, Vol. 649. New York Academy of Sciences, New York, NY, 1992. 

Brownell, GX., et al. Positron Tomography and Nuclear Magnetic Resonance Imaging, Science, 215, 619-626 (1982). 

Li et al. [196] studied the sites of ion delivery in the eye during iontophoresis. Using nuclear magnetic resonance imaging (MRI) and a probe ion (Mn2+), the study compared transscleral with transcorneal iontophoresis. The results have shown that transscleral iontophoresis delivered the ion into the vitreous, whereas transcorneal iontophoresis delivered the ion into the... 

Kuo, M.I., Anderson, M.E., and Gunasekaran, S. 2003. Determining effects of freezing on pasta filata and non-pasta filata mozzarella cheeses by nuclear magnetic resonance imaging. J. Dairy Sci. 86, 2525-2536. 

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