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Reference materials, nuclear magnetic resonance

The crystalline mineral silicates have been well characterized and their diversity of stmcture thoroughly presented (2). The stmctures of siHcate glasses and solutions can be investigated through potentiometric and dye adsorption studies, chemical derivatization and gas chromatography, and laser Raman, infrared (ftir), and Si Fourier transform nuclear magnetic resonance ( Si ft-nmr) spectroscopy. References 3—6 contain reviews of the general chemical and physical properties of siHcate materials. [Pg.3]

While the broad mission of the National Bureau of Standards was concerned with standard reference materials, Dr. Isbell centered the work of his laboratory on his long interest in the carbohydrates and on the use of physical methods in their characterization. Infrared spectroscopy had shown promise in providing structural and conformational information on carbohydrates and their derivatives, and Isbell invited Tipson to conduct detailed infrared studies on the extensive collection of carbohydrate samples maintained by Isbell. The series of publications that rapidly resulted furnished a basis for assigning conformations to pyranoid sugars and their derivatives. Although this work was later to be overshadowed by application of the much more powerful technique of nuclear magnetic resonance spectroscopy, the Isbell— Tipson work helped to define the molecular shapes involved and the terminology required for their description. [Pg.425]

There are two basic ways to look for explosive material. They differ in their point of focus. Some sensors seek the mass of explosive material within a device. These are particularly useful when the device is well sealed and its surface is well cleaned of stray explosive molecules, or when the explosive being used is nonaromatic, that is, it does not readily release molecules from its bulk. We will refer to these as bulk sensors. They include X-ray techniques, both transmission and backscatter neutron activation in several techniques y -ray excitation, in either transmission or backscatter modes and nuclear resonance techniques, either nuclear magnetic resonance (NMR) or nuclear quadrupole resonance (NQR). Bruschini [1] has described these thoroughly. They are also described by the staff of the Jet Propulsion Laboratory [2], The following forms a very brief synopsis. [Pg.4]

Ghisalberti EL, Godofrey IM (1998) Apphcation of nuclear magnetic resonance spectroscopy to the analysis of organic archaeological materials. Stud Conserv 43 215-230, and references therein. [Pg.143]

JK Baker, CW Myers. One-dimensional and two-dimensional I I- and 13C-nuclear magnetic resonance (NMR) analysis of vitamin E raw materials or analytical reference standards. Pharm Res 8 763-770, 1991. [Pg.507]

Nuclear Magnetic Resonance Procedure—Small samples of the original oils and the volatile materials and residues obtained during the special Noack tests were analyzed by P NMR at Washington University (St. Louis, MO). The spectra were obtained either on a 500 MHz Varian NMR equipped with a 10 mm probe or on a 600 MHz Varian NMR equipped with a 5 mm probe. Samples were diluted with 10-15 % chloroform-d (CDC13), which also served as an internal reference for establishing spectral positions. Average data accumulation time for these spectra was one hour. As mentioned, a conjoined paper [24] covers this aspect of the study. [Pg.244]

This section provides a broad overview of the application of NMR spectroscopy to crystallinity determination in polymers. The approaches illustrated are certainly not exhaustive of those available for the powerful NMR technique and the interested reader is encouraged to consult one or more of the reference books on NMR spectroscopic investigations of polymeric materials (51-53) (see NUCLEAR Magnetic Resonance). [Pg.1994]


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See also in sourсe #XX -- [ Pg.112 ]




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