Nuclear cellulosics

Online detection using 4H nuclear magnetic resonance (NMR) is a detection mode that has become increasingly practical. In a recent application, cell culture supernatant was monitored on-line with 1-dimensional NMR for trehalose, P-D-pyranose, P-D-furanose, succinate, acetate and uridine.33 In stopped-flow mode, column fractions can also be analyzed by 2-D NMR. Reaction products of the preparation of the neuromuscular blocking compound atracurium besylate were separated on chiral HPLC and detected by 4H NMR.34 Ten isomeric peaks were separated on a cellulose-based phase and identified by online NMR in stopped-flow mode. 

Uses Plasticizer for lacquers, plastics, cellulose esters, and vinyl resins heat-exchange liquid carbonless copy paper systems in aircraft hydraulic fluids solvent extraction of metal ions from solution of reactor products uranium extraction and nuclear fuel reprocessing pigment grinding assistant antifoaming agent solvent for nitrocellulose and cellulose acetate. 

The structural homogeneity of the various cellulose triacetate fractions obtained by fractional precipitation was established by both Infrared and nuclear magnetic resonance spectroscopy. 

Newman, R. H., Davies, L. M., Harris, P. J. (1996). Solid-state C nuclear magnetic resonance characterization of cellulose in the cell walls of Arabidopsis thaliana leaves. Plant Physiol, III, 475 85. 

Materials. The water used for all purposes was double-distilled (once with glassware) and deionized (final conductance was less than 1 X 10"6 ohm1 cm."1). Stearic acid (obtained from Sigma Chemical Co.) was at least 99% pure as determined by silica gel thin-layer chromatography (4), and the synthetic L-a(/ ,y-dipalmitoyl) lecithin was about 90% pure (see Ref. 13 for analysis). The ATP-14C and its derivatives were obtained from Nuclear-Chicago or New England Nuclear Corp. and were found to be 95-98% pure as determined by cellulose thin-layer chromatography (16). 

Nuclear extracts can be fractionated by chromatography on DEAE-cellulose to give three peaks of RNA polymerase activity (the use of column chromatography is explained in chapter 6). These three peaks correspond to three different RNA polymerases (I, II, and III), which differ in relative amount, cellular location, type of RNA synthesized, subunit structure, response to salt and divalent cation concentrations, and sensitivity to the mushroom-derived toxin a-amanitin. The three polymerases and some of their properties are summarized in table 28.4. 

Fabrication of Self-Supporting Oxide Targets by Cationic Adsorption in Cellulosic Membranes and Thermal Decomposition," Thomas C. Quinby in Proceeding of Workshop 1983 of the International Nuclear Target Development Society, Argonne National Laboratory, Argonne, IL, Sept. 7-9, 1983. ANY/PHY-84-2 ... 

Nuclear Magnetic Resonance (NMR) - NMR spectra of cellulose nitrate-g-poly(methyl methacrylate) and cellulose nitrate were recorded in deuterated acetone using Perkin-Elmer-R-32 (90 MHz). 

The nuclear magnetic resonance spectra of cellulose nitrate and of cellulose-g-poly(methyl methacrylate) after separation from cellulose nitrate and poly(methyl methacrylate), are shown in Figures 3 and 4, respectively. The graft copolymer shows the presence of C1CH3 proton at 1.06, indicating the presence of poly(methyl methacrylate) chains attached to cellulose nitrate. 

Now that the range of likely shapes has been defined by experiments on related molecules and by energy calculations, we focus on the details of specific structures that have been observed for real, crystalline cellulose molecules, primarily by x-ray, neutron, and electron diffraction studies. A number of landmark concepts have been established with electron microscopy, as well. Infrared (IR), Raman, and nuclear magnetic resonance (NMR) spectroscopy have all also been important in the quest for understanding cellulose structure. Such data, while so far not able to provide complete definitive structures themselves, constitutes additional criteria that any proposed structure must be able to explain. In addition, unlike crystallography, the resolution of spectroscopic methods is not directly affected by the dimensions of the... 

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