A water-soluble pectin SB_~1-1 was isolated and purified from the root of Panax ginseng C. A. Mey. The HPLC analysis indicates that SB_~1-1 is homogenous. Its molecular weight was estimated via gel filtration to be 10...A water-soluble pectin SB_~1-1 was isolated and purified from the root of Panax ginseng C. A. Mey. The HPLC analysis indicates that SB_~1-1 is homogenous. Its molecular weight was estimated via gel filtration to be 10000. The GC analysis indicated that it contains the monosaccharides of GalA, Gal, Ara and Rha. Their molar ratio is 2.10∶1.00∶0.12∶0.13. Partial hydrolysis with acid, pectinase treatment, periodate oxidation, Smith degradation, methylation analyses, GC/MS analyses and NMR analyses were used for the structure analyses of SB_~1-1 . The results reveal that SB_~1-1 has a lower branched structure. The main chain is composed of GalA and Gal; the inner part is α-1,4-linked-GalA; the border is 1,4-linked-Gal. Some of the 1,4-linked-GalA and 1,4-linked-Gal residues are substituted at O6. On an average, there is one branch for every ten hexose residues. The side chain is composed of 1,6-linked-Gal and 1,3,6-linked-Gal. The nonreduced end is composed of Rha, Ara and Gal. The main glycosidic link of SB_~1-1 has an α configuration.展开更多
A grade-tonnage model is established according to the analysis of 72 porphyry copper deposits recorded in 'The Mineral Resources Data Base of China'. Based on the analysis of frequency histogram, the cumulativ...A grade-tonnage model is established according to the analysis of 72 porphyry copper deposits recorded in 'The Mineral Resources Data Base of China'. Based on the analysis of frequency histogram, the cumulative frequency distributing graph and the theoretical model with double logarithmic coordinates of copper deposits, the typical mathematical characteristics of grade-tonnage model of porphyry copper deposits are clarified.展开更多
文摘A water-soluble pectin SB_~1-1 was isolated and purified from the root of Panax ginseng C. A. Mey. The HPLC analysis indicates that SB_~1-1 is homogenous. Its molecular weight was estimated via gel filtration to be 10000. The GC analysis indicated that it contains the monosaccharides of GalA, Gal, Ara and Rha. Their molar ratio is 2.10∶1.00∶0.12∶0.13. Partial hydrolysis with acid, pectinase treatment, periodate oxidation, Smith degradation, methylation analyses, GC/MS analyses and NMR analyses were used for the structure analyses of SB_~1-1 . The results reveal that SB_~1-1 has a lower branched structure. The main chain is composed of GalA and Gal; the inner part is α-1,4-linked-GalA; the border is 1,4-linked-Gal. Some of the 1,4-linked-GalA and 1,4-linked-Gal residues are substituted at O6. On an average, there is one branch for every ten hexose residues. The side chain is composed of 1,6-linked-Gal and 1,3,6-linked-Gal. The nonreduced end is composed of Rha, Ara and Gal. The main glycosidic link of SB_~1-1 has an α configuration.
文摘A grade-tonnage model is established according to the analysis of 72 porphyry copper deposits recorded in 'The Mineral Resources Data Base of China'. Based on the analysis of frequency histogram, the cumulative frequency distributing graph and the theoretical model with double logarithmic coordinates of copper deposits, the typical mathematical characteristics of grade-tonnage model of porphyry copper deposits are clarified.