Nuclear magnetic resonance colloids

P. T. Callaghan, K. W. Jolley, R. S. J. Humphrey 1983, (Diffusion of fat and water in cheese as studied by pulsed field gradient nuclear magnetic-resonance), Colloid Interface Sci. 93, 521. 

Chul, M Phillips, R McCarthy, M, Measurement of the Porous Microstructure of Hydrogels by Nuclear Magnetic Resonance, Journal of Colloid and Interface Science 174, 336, 1995. Cohen, Y Ramon, O Kopeknan, IJ Mizrahi, S, Characterization of Inhomogeneous Polyacrylamide Hydrogels, Journal of Polymer Science Part B Polymer Physics 30, 1055, 1992. Cohen Addad, JP, NMR and Statistical Structures of Gels. In The Physical Properties of Polymeric Gels Cohen Addad, JP, ed. Wiley Chichester, UK, 1996 39. 

While the nuclear magnetic resonance (NMR) technique has widely been used to study diffusion processes of normal liquids, solids, or colloidal systems, there are only a few applications to molten salts. The spin echo self-diffusion method with pulsed field gradients was applied to molten salts by Herdlicka et al. "" There is no need to set up or maintain a concentration gradient. 

Part II Macromolecules Catalysis Colloid Science Electrochemistry Electron Spin Resonance Environmental Chemistry Genetal and Synthetic Methods Mass Spectrometry Nuclear Magnetic Reson n e Organometallic Chemistry Organophosphorus Chemistry Photochemistry... 

To detect dynamic featnres of colloidal preparations, additional methods are required. Nuclear magnetic resonance spectroscopy allows a rapid, repeatable, and noninvasive measurement of the physical parameters of lipid matrices withont sample preparation (e.g., dilution of the probe) [26,27]. Decreased lipid mobility resnlts in a remarkable broadening of the signals of lipid protons, which allows the differentiation of SLN and supercooled melts. Because of the different chemical shifts, it is possible to attribute the nuclear magnetic resonance signal to particnlar molecnles or their segments. 

Y. Pan, P- F rotational-echo double resonance nuclear magnetic resonance experiment on fluoridated hydroxyapatite. Solid State Nucl. Magn. Reson. 5 (1995) 263-268. L. Wu, W. Forsling, P.W. Schindler, Surface complexation of calcium mineral in aqueous solution, surface protonation at fluorapatite surface, J. Colloid Interface Sci. 147 (1991) 178-185. 

Lopez-Quintela MA (2003) Synthesis of nanomaterials in microemulsions formation mechanisms and growth control. Curr Opin Colloid Interface Sci 8 137-144 Lopez-Quintela MA, Tojo C, Blanco MC, Rio LG, Leis JR (2004) Microemulsion dynamics and reactions in microemulsions. Curr Opin Colloid Interface Sci 9 264-278 Maitra A (1984) Determination of Size Parameters of Water Aerosol Ot Oil Reverse Micelles from Their Nuclear Magnetic-Resonance Data. J Phys Chem 88 5122-5125... 

With the advent of advanced characterization techniques such as multiple detector liquid exclusion chromatography and - C Fourier transform nuclear magnetic resonance spectroscopy, the study of structure/property relationships in polymers has become technically feasible (l -(5). Understanding the relationship between structure and properties alone does not always allow for the solution of problems encountered in commercial polymer synthesis. Certain processes, of which emulsion polymerization is one, are controlled by variables which exert a large influence on polymer infrastructure (sequence distribution, tacticity, branching, enchainment) and hence properties. In addition, because the emulsion polymerization takes place in an heterophase system and because the product is an aqueous dispersion, it is important to understand which performance characteristics are influended by the colloidal state, (i.e., particle size and size distribution) and which by the polymer infrastructure. 

Keywords Colloids, Nuclear Magnetic Resonance, Relaxation, Diffusion. 

Porion, P., Al-Mukhtar, M., Meyer, S., Faugere, A.M., van der Maarel, J.R.C. and Delville, A. (2001) Nematic Ordering of Suspensions of Charged Anisotropic Colloids Detected by 23Na Nuclear Magnetic Resonance. The Journal of Physical Chemistry B... 

A recent book on physical chemistry,5 written by a scientist6 and aimed primarily at other scientists, contains substantial historical information on the beginnings of physical chemistry and on various topics, such as chemical spectroscopy, electrochemistry, chemical kinetics, colloid and surface chemistry, and quantum chemistry. The book also discusses more general topics, such as the development of the physical sciences and the role of scientific journals in scientific communication. The same author has written a brief account of the development of physical chemistry after 1937,7 emphasizing the application of quantum theory and the invention of new experimental methods stopped-flow techniques (1940), nuclear magnetic resonance... 

Hakansson B, Soderman O, Balinov B. Nuclear magnetic resonance of emulsions. In Hubbard AT, editor. Encyclopedia of Surface and Colloid Science. Vol. 3, New York Marcel Dekker 2002. 

For NMR of solid-liquid interfaces, see K.J. Packer. Nuclear Spin Relaxation Studies of Molecules Adsorbed on Surfaces, in Progress in Nuclear Magnetic Resonance Spectroscopy, J.W. Emsley, J. Feeney and L.H. Sutcliffe. Eds., Vol. 3. Pergamon (1967), chapter 3. 87 A collection of papers on magnetic resonance in colloid and interface science can be found in Colloids Surf 72 (1993). 

Amino-acids, Peptides, and Proteins Biosynthesis Carbohydrate Chemistry Catalysis Colloid Science Electrochemistry Electron Spin Resonance Electronic Structure and Magnetism of Inorganic Compounds Environmental Chemistry General and Synthetic Methods Heterocyclic Chemistry Inorganic Biochemistry Macromolecular Chemistry Mass Spectrometry Nuclear Magnetic Resonance Organic Compounds of Sulphur,... 

J. S. Bradley, J. M. Millar, and E. W. HiU. Surface-chemistry on colloidal metals - a high-resolution nuclear-magnetic-resonance study of carbon-monoxide adsorbed on metallic palladium crystallites in colloidal suspension. J. Am. Chem. Soc., 113 4016 017, 1991... 

A variety of spectroscopic techniques have been applied to DOC isolated from seawater by cross-flow ultrafiltration or adsorption onto XAD resins. The two techniques isolate very different organic fractions from seawater. Hydrophobic fractions (such as marine humic material) are isolated on XAD resins [48], whereas the organic matter extracted by ultrafiltration is retained primarily on the basis of its molecular size and shape [49], resulting in isolates rich in nitrogen and carbohydrates (polysaccharides). Nuclear magnetic resonance (NMR) spectroscopy has proven successful in distinguishing between the specific structures of XAD-bound humics and the carbohydrates concentrated into colloidal size fractions. 

Various improvements have broadened the research in the field of zeolite membranes and films, such as the development of new synthesis procednres, the use of new supports with specific characteristics (monoliths, foams, etc.), or the use of modified supports by means of masking or grafting techniques, the application of new analytical techniques (isotopic-transient experiments, permporometry, pulsed field gradient nuclear magnetic resonance [NMR], interference microscopy, IR microscopy, etc.), the control of the orientation of the crystals (by means of covalent linkages, synthesis conditions, etc.) and of the thickness of the membranes, and the preparation of new zeolites as membranes or new zeolite-related materials. In addition, a variety of zeolites can now be prepared as colloidal systems with particle dimensions ranging from tens to a few hnndred nanometers. 

Among the several experimental techniques for studying colloid and sol-gel chemistry, perhaps the most powerful one is nuclear magnetic resonance (NMR) spectroscopy. NMR allows investigation of these systems by a combination of structural information, obtained through lineshape analysis and chemical shift data, and indirect information from dynamic measurements of spin relaxation and diffusion. 

Nuclear magnetic resonance studies have proved valuable for the characterization of other colloidal oxides and hydroxides. Some selected examples of such studies are shown in the following paragraphs. 

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