The acid-base properties of supports have an enormous impact on catalytic reactions to regulate the selectivity and activity of supported catalysts. Herein, a train of Pd-X-UiO-66 (X = NO , NH , and CH ) catalysts with different acidity/alkalinity functional groups and encapsulated Pd(II) species is first developed, whose activities in dimethyl carbonate (DMC) catalysis are then investigated in details. Thereinto, the Pd-NO -UiO-66 catalyst with acidity functionalization exhibits the best catalytic behavior: the DMC selectivity stemmed from methyl nitrite (MN) is up to 68%, the conversion of CO is 73.
View Article and Find Full Text PDFAs part of our ongoing search for novel therapeutic structures from microorganism, the chemical examination of marine fungus Phoma sp. resulted in the isolation of ergosterol, ergosterol peroxide (EP), and 9,11-dehydroergosterol peroxide (DEP). The bioassay results demonstrated that the three isolates reduced the viability of various cancer cells, with EP being highest in human lung cancer cell line A549 cells.
View Article and Find Full Text PDFIn this study, we report the structure and function of a lectin from the sea mollusk Crenomytilus grayanus collected from the sublittoral zone of Peter the Great Bay of the Sea of Japan. The crystal structure of C. grayanus lectin (CGL) was solved to a resolution of 1.
View Article and Find Full Text PDFRing-opening isomerization from ring-shaped isomers to chain-shaped isomers of N(8)H(8) has been studied by a density function B3LYP method at 6-311+ +G** level. 20 ring-shaped isomers have been found to be able to transform into chain-shaped isomers, with 20 possible transition states got by ring-opening structure optimization. Furthermore, the ring-openings have been found in the longer N-N single bond by analyzing the length change of N-N bond of ring-shaped isomers in ring-opening processes.
View Article and Find Full Text PDFFruit ripening is associated with a number of physiological and biochemical changes. They include degradation of chlorophyll, synthesis of flavor compounds, carotenoid biosynthesis, conversion of starch to sugars, cell wall solublisation and fruit softening. These changes are brought about by the expression of specific genes.
View Article and Find Full Text PDFAccording to its restriction sites, fragments of 1573 bp, 1197 bp, 896 bp and 795 bp were obtained from the 5' promoter region of wml1 and fused with the coding sequence of the GUS gene. Constructs containing these fragments were introduced into tomato plants via Agrobacterium-mediated transformation. Histochemical assay of GUS expression in transgenic tomato plants revealed that fragments of 1573 bp, 1197 bp, 896 bp were able to direct GUS expression in fruits of 15, 30, 45 days after anthesis with the expression level of GUS increasing with fruit development, but not in leaves, stems and roots.
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