Chromatography studies

Molecular weights of PVDC can be determined directly by dilute solution measurements in good solvents (62). Viscosity studies indicate that polymers having degrees of polymerization from 100 to more than 10,000 are easily obtained. Dimers and polymers having DP < 100 can be prepared by special procedures (40). Copolymers can be more easily studied because of thek solubiUty in common solvents. Gel-permeation chromatography studies indicate that molecular weight distributions are typical of vinyl copolymers. 

Gel-permeation chromatography studies of epoxy resins prepared by the taffy process shown n values = 0, 1, 2, 3, etc, whereas only even-numbered repeat units are observed for resins prepared by the advancement process. This is a consequence of adding a difunctional phenol to a diglycidyl ether derivative of a difunctional phenol in the polymer-forming step. 

Based on results of NMR and of gel permeation chromatography studies, a simplified composition for the PGCBA that yielded the epoxide equivalent of 0.137 kg/mol was assumed. The molar fraction of tetra functional molecules was taken as v4 = 0.45 and of trifunctional molecules was taken as v3 = 0.55. 

Gel permeation chromatography studies using both refractive index and UV(260 nm) absorption detections have confirmed that both Acacia Senegal and Acacia seyal gums consist of three main components (Islam et al., 1997, Idris et al., 1998, Williams Phillips, 2000, Al Assaf 2006) ... 

The clearing effect of heparin on blood is associated with release of the triglyceride-hydrolyzing enzyme lipoproteinlipase (LPL) from the surface of endothelial cells.458,459 In addition to a number of apparently equivalent lipases from different tissues,459 heparin also releases a hepatic lipase.460,461 As suggested by the results of affinity-chromatography studies, this release is probably associated with binding of the polysaccharide to the enzyme. 62,463 Because other polyanions,464 including the... 

The degrees of polymerization determined by mass spectroscopy are corroborated by vapor pressure osmometry and gel permeation chromatography studies (21). 

Hartmann, M., A. Piippl et al. (1996). Ethylene dimerization and butene isomerization in nickel-containing MCM-41 and A1MCM-41 mesoporous molecular sieves An electron spin resonance and gas chromatography study. J. Phys. Chem. 100 9906-9910. 

Dondi M, Flieger M, Olsovska J, Polcaro CM, Sinibaldi M (1999) High-performance liquid chromatography study of the enantiomer separation of chrysanthemic acid and its stationary phase. J Chromatogr A 859 133-142... 

Infrared spectra were recorded on a Perkin Elmer Model 567 Spectrophotometer. Ultraviolet spectra were obtained on a Cary 1756 Spectrophotometer. Gas chromatograms were recorded on a Tracor Model 220 with electron capture detector. High pressure liquid chromatography studies were conducted with a Waters Model ALC-200 with ultraviolet and refractive index detectors. 

S. Carda-Broch, J. Esteve-Romero and M.C. Garca-Alvarez-Coque, Furosemide assay in pharmaceuticals by micellar liquid chromatography study of the stability of the drug, J. Pharm. Biomed. Anal., 23(5), 803-817 (2000). 

Bican, P. and Blanc, B. 1982. Milk protein analysis—a high-performance chromatography study. Milchwissenschaft 37, 592-593. 

FTIR studies indicate that commercial TGDDM (MY720, Ciba Geigy) contains 15-20% less epoxide groups than the pure tetrafunctional TGDDM epoxide molecule 9-U). Liquid chromatography studies indicate that the missing O... 

Describe the appearance of the whey before chromatography. Study your experimentally derived plot of A28Q vs. Sephadex or affinity column fraction number. How many major protein peaks are present Which peak has the greatest amount of protein Do you believe that each peak contains a single type of protein, or does it contain a mixture If each peak represents a mixture of proteins, what one feature does each protein have in common ... 

Incubation of lake water with 32P or 33P as tracers and subsequent gel chromatography reveals that a major pathway exists between dissolved orthophosphate and the particulate phase (3, 5-7). Low-molecular-weight phosphorus forms in the presence of bacteria and algae. SUP is present in the low-molecular-weight fraction and is classified as individual DOP compounds unassociated with particulate or colloidal material. The HMW fraction found in gel chromatography studies is characterized as a colloid that contains phosphorus compounds or incorporates orthophosphate. The colloidal material then releases orthophosphate, replenishing the dissolved phosphorus cycle. In some eutrophic lakes the HMW SRP fraction can make... 

Hydrophobic chromatography studies of proteins intramolecularly crosslinked to minimize unfolding suggest that .. . the effective hydrophobicity of proteins is due in part to the extent to which buried hydrophobic residues are exposed by protein unfolding (Ref.83), p. 97). 

At 0°C, paclitaxel reacts with the carbonates at its most reactrtoydtoxy group. When the nitro function was reduced under mild conditions, using zinc and acetic acid, complete disappearance of the starting dendron and release of the paclitaxel were observed, and these results were supported by thin layer chromatography studies. Proton-NMR ccmed these results and demonstrated complete... 

R. W. Kane and J. D. Timpa, A high-performance liquid chromatography study of D-cellobiose degradation under Fenton conditions, J. Carbohydr. Chem., 11 (1992) 779-797. 

Kilduff, J. E., T. Karanfil, Y. P. Chin, and W. J. Weber. 1996. Adsorption of natural organic polyelectrolytes by activated carbon A size-exclusion chromatography study. Environmental Science and Technology 30 1336. 

Lapcik, L., Jr., Chabreacek, P., and Staasko, A., Photodegradation of hyaluronic acid EPR and size exclusion chromatography study, Biopolymers, 31, 1429, 1991. 

Hashimoto S, Miyata T, Washino M, Kawakami W. A liquid chromatography study on the radiolysis of phenol in aqueous solution. Environ Sci Technol 1979 13 71-75. 

Edelman, A. Fradet, A., "Inverse Gas Chromatography Study of Some Alkyl Trinitrate Polymer Systems," Polymer, 30, 324 (1989a). 

Galin, M., "Gas-Liquid Chromatography Study of Polyethylene oxide)- Solvent Interactions Estimation of Polymer Solubility Parameter," Polymer, 24, 865 (1983). 

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