Abstract Anthrylsulfides were obtained in high yields in the reactions of 9-nitroanthracene 1 with thiols. The reactions with thiolates resulted in the formation of aci-9,9′-dinitro-10,10′-dihydro-10,10′-bianthryl 2 via a 9-nitroanthracene anion radical.
Pulse discharge sintering (PDS) technique was employed to synthesize the ternary compound Ti3SiC2 from four starting powder mixtures. The experimental results demonstrated that when the starting material of 3Ti/Si/2C or 3Ti/SiC/C was used high content of the secondary phase, TiC, higher than 30 mass%, was found in the sintered material. When TiC powder as starting material was used (Ti/Si/2TiC) in the same stoichiometric composition, however, the final sintered product contained low TiC content of a few percent. Further adjusting the composition to the off-stoichiometric of 2Ti/2Si/3TiC, the content of the secondary phase TiC was further controlled to be around 1 mass%. In the materials sintered from Ti/Si/2TiC and 2Ti/2Si/3TiC an optimum sintering temperature exists at 1573 K, at which the highest Ti3SiC2 phase purity was achieved. When sintered at the optimum temperature a density of higher than 99% was obtained. At the optimum sintering temperature, both the phase purity and the density of the material sintered from 2Ti/2Si/3TiC showed very little dependence on the sintering time ranging from a few minutes to four hours, indicating the phase stability at this temperature.
Inorganic carbon transport during photosynthesis of cyanobacterium Anabaena variabilis grown under ordinary air was investigated by supplying 14CO2 or H14CO3− solution to three different strains. Both CO2 and HCO3− were accumulated within the algal cells. In the cell suspension from which dissolved inorganic carbon had been depleted by pre-illumination, CO2 was transported and accumulated faster than HCO3−. When the concentration of HCO3− injected into the cell suspension of A. variabilis M3 was 25 times as high as that of CO2 (the expected ratio at equilibrium at pH 7.8), the initial rates of fixation of both inorganic carbon species were practically the same. On the other hand, when 14CO2 or H14CO3− was added under steady state photosynthetic conditions, both carbon species were transported at similar rates. The ratio of fixed to transported carbon measured after the initial 5 s was only 23–27% regardless of the carbon species supplied. This percentage is much lower than that reported for Chlorella cells.
