Increasing input of nutrients is leading to significant eutrophication in aquatic systems across the globe. Toxin production in those blooms is correlated with high cell density. A study was done to investigate the ef...Increasing input of nutrients is leading to significant eutrophication in aquatic systems across the globe. Toxin production in those blooms is correlated with high cell density. A study was done to investigate the effects of initial cell density on the growth rate of the potentially toxic cyanobacterium Microcystis aeruginosa, in unfiltered lake water as well a common algal growth medium under laboratory conditions. Five treatments were established in the laboratory varying the initial cell density of M. aeruginosa and the growth medium. Unfiltered lake water was inoculated with a low, medium, and high initial cell density and Bold’s medium was inoculated with low and high initial cell densities. There was a significant difference in final cell density between the lake water treatments with the high inoculum of cell treatment reaching the highest final cell density. There was also a significant difference in final cell density between the Bold’s medium treatments. These results indicate there is a relationship between initial cell density of M. aeruginosa and final cell density, however, the results are similar when nutrients are available. Diverse algal communities can keep toxin producing algae in low density therefore precluding the need of toxin production.展开更多
There is considerable interest in potential aneutronic fusion reactors. One possible reaction is^(11)B(p,a)2a.However, the emitted alpha particles are energetic enough to generate neutrons by interacting with boron in...There is considerable interest in potential aneutronic fusion reactors. One possible reaction is^(11)B(p,a)2a.However, the emitted alpha particles are energetic enough to generate neutrons by interacting with boron inside the reactor through the ^(11)B(α,n)^(14N) and ^(10)B(α,n)^(13)N reactions.To aid in evaluating neutron production within this potential aneutronic reactor, the total cross sections were measured for the ^(11)B(α,n)^(14N) reaction between 2 and 6 MeV and for the ^(10)B(α,n)^(13)N reaction between 2 and 4.8 MeV. The results are presented and compared with previously reported results.展开更多
文摘Increasing input of nutrients is leading to significant eutrophication in aquatic systems across the globe. Toxin production in those blooms is correlated with high cell density. A study was done to investigate the effects of initial cell density on the growth rate of the potentially toxic cyanobacterium Microcystis aeruginosa, in unfiltered lake water as well a common algal growth medium under laboratory conditions. Five treatments were established in the laboratory varying the initial cell density of M. aeruginosa and the growth medium. Unfiltered lake water was inoculated with a low, medium, and high initial cell density and Bold’s medium was inoculated with low and high initial cell densities. There was a significant difference in final cell density between the lake water treatments with the high inoculum of cell treatment reaching the highest final cell density. There was also a significant difference in final cell density between the Bold’s medium treatments. These results indicate there is a relationship between initial cell density of M. aeruginosa and final cell density, however, the results are similar when nutrients are available. Diverse algal communities can keep toxin producing algae in low density therefore precluding the need of toxin production.
基金supported by U.S. Department of Energy Grant Nos.DE-FG02-97ER41033 and DE-FG02-97ER41046
文摘There is considerable interest in potential aneutronic fusion reactors. One possible reaction is^(11)B(p,a)2a.However, the emitted alpha particles are energetic enough to generate neutrons by interacting with boron inside the reactor through the ^(11)B(α,n)^(14N) and ^(10)B(α,n)^(13)N reactions.To aid in evaluating neutron production within this potential aneutronic reactor, the total cross sections were measured for the ^(11)B(α,n)^(14N) reaction between 2 and 6 MeV and for the ^(10)B(α,n)^(13)N reaction between 2 and 4.8 MeV. The results are presented and compared with previously reported results.