Semihydrogenation of internal alkynes catalyzed by the air-stable imidazolyl amino [MoSCl(ImNH)] cluster selectively affords the ()-alkene under soft conditions in excellent yields. Experimental results suggest a sulfur-based mechanism with the formation of a dithiolene adduct through interaction of the alkyne with the bridging sulfur atoms. However, computational studies indicate that this mechanism is unable to explain the experimental outcome: mild reaction conditions, excellent selectivity toward the ()-isomer, and complete deuteration of the vinylic positions in the presence of CDOD and CHOD.
View Article and Find Full Text PDFThe reaction of three [Fe(TSC)] complexes, where TSC is a pyridine-substituted thiosemicarbazone of the HDpT or HBpT families, with HO in acetonitrile solution does not result in the accumulation of the corresponding [Fe(TSC)] complexes. Instead, a mixture of diamagnetic low-spin Fe species is generated. According to the MS spectra, those species result from the sequential addition of up to five oxygen atoms to the complex.
View Article and Find Full Text PDFThe African bichir (Polypterus senegalus) is a living representative of Polypteriformes. P. senegalus possesses teeth composed of dentin covered by an enameloid cap and a layer of collar enamel on the tooth shaft, as in lepisosteids.
View Article and Find Full Text PDFAquaculture constitutes an alternative source for food production and contributes to a reduction in the indiscriminate catching of aquatic organisms in their natural environment. However, high mortality during the larval state remains a challenge in this sector, mainly because of factors such as diet and diseases caused by pathogens. Therefore, growth and health management is a key strategy for sustainable aquaculture.
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