Arsenic(As)speciation for the phytoremediation by the Chinese brake fern was studied.In particular,the mechanism of how plants induce compounds containing thiol(SH)and proteins by As exposure in terms of the relations...Arsenic(As)speciation for the phytoremediation by the Chinese brake fern was studied.In particular,the mechanism of how plants induce compounds containing thiol(SH)and proteins by As exposure in terms of the relationship between As and phosphate uptaken into plant cells was examined.Pteris vittata callus could effciently reduce As(V)to As(III)by the rapid introduction of reductase and synthesize thiols leading to phytochelatins production.Furthermore,Pteris vittata could control phosphate concentration in t...展开更多
A new image reconstruction method was developed for a Compton camera. A simulation to determine a γ-ray source position was performed by using the simulation tool, GEANT4. An image reconstruction was made in two step...A new image reconstruction method was developed for a Compton camera. A simulation to determine a γ-ray source position was performed by using the simulation tool, GEANT4. An image reconstruction was made in two steps. First, a three dimensional image was constructed and projected in one selected plane, then the points from each ellipse was picked up by taking the peak points of a density distribution of crossing points between the ellipse and the first step image. The second step procedure improved the accuracy and the spatial resolution of a position de- termination significantly, comparing with the image obtained by only the first step. The accuracy and the resolution for a point source were obtained to be about 0.02 mm and (1.35±0.15) mm, respectively. The same procedure was applied to an imaging of the distributed γ-ray source.展开更多
We measured the main plasma parameters（density of electron,temperature of electron and ion confinement time）and beam intensity of various heavy ions as a function of B<sub>min</sub>.The B<sub>min&l...We measured the main plasma parameters（density of electron,temperature of electron and ion confinement time）and beam intensity of various heavy ions as a function of B<sub>min</sub>.The B<sub>min</sub> strongly affects the field gradient at the resonance zone,consequently the plasma parameters and beam intensity are changed. Based on these experimental results,we started to construct new 18GHz ECRIS and make a detailed design of the 28GHz SC-ECRIS for RIKEN RI beam factory project.展开更多
At RIKEN,three ECR ion sources（10GHz ECRIS,18GHz ECRIS and liquid He-free SC-ECRIS） are operated as external ion sources of heavy ion accelerators.In the last year,multi-charged uranium ion beam was produced from 18...At RIKEN,three ECR ion sources（10GHz ECRIS,18GHz ECRIS and liquid He-free SC-ECRIS） are operated as external ion sources of heavy ion accelerators.In the last year,multi-charged uranium ion beam was produced from 18GHz ECRIS by using UF<sub>6</sub> and the <sup>238</sup>U ion was successfully accelerated by the accelerator complex which consists of the RFQ linear accelerator,RIKEN heavy ion linear accelerator（RILAC）and RIKEN ring cyclotron accelerator（RRC）.The typical beam intensity of<sup>238</sup>U<sup>14+</sup> was about 2pμA on faraday cup after analysing magnet.<sup>70</sup>Zn beam was still supplied for the new super-heavy element search experiment with insertion method.Intense beam of<sup>70</sup>Zn<sup>16+</sup> was produced for long term（～43 days）without vacuum break and remarkably low material consumption rate（～100μgr/h）.We already supplied Zn beam longer than 200 days for this experiment.<sup>48</sup>Ca ion was also produced by insertion method using<sup>48</sup>CaO rod for the nuclear physics experiment.In this contribution,we will present ion source parameter and techniques for production of each of the metal ions.展开更多
文摘Arsenic(As)speciation for the phytoremediation by the Chinese brake fern was studied.In particular,the mechanism of how plants induce compounds containing thiol(SH)and proteins by As exposure in terms of the relationship between As and phosphate uptaken into plant cells was examined.Pteris vittata callus could effciently reduce As(V)to As(III)by the rapid introduction of reductase and synthesize thiols leading to phytochelatins production.Furthermore,Pteris vittata could control phosphate concentration in t...
文摘A new image reconstruction method was developed for a Compton camera. A simulation to determine a γ-ray source position was performed by using the simulation tool, GEANT4. An image reconstruction was made in two steps. First, a three dimensional image was constructed and projected in one selected plane, then the points from each ellipse was picked up by taking the peak points of a density distribution of crossing points between the ellipse and the first step image. The second step procedure improved the accuracy and the spatial resolution of a position de- termination significantly, comparing with the image obtained by only the first step. The accuracy and the resolution for a point source were obtained to be about 0.02 mm and (1.35±0.15) mm, respectively. The same procedure was applied to an imaging of the distributed γ-ray source.
文摘We measured the main plasma parameters（density of electron,temperature of electron and ion confinement time）and beam intensity of various heavy ions as a function of B<sub>min</sub>.The B<sub>min</sub> strongly affects the field gradient at the resonance zone,consequently the plasma parameters and beam intensity are changed. Based on these experimental results,we started to construct new 18GHz ECRIS and make a detailed design of the 28GHz SC-ECRIS for RIKEN RI beam factory project.
文摘At RIKEN,three ECR ion sources（10GHz ECRIS,18GHz ECRIS and liquid He-free SC-ECRIS） are operated as external ion sources of heavy ion accelerators.In the last year,multi-charged uranium ion beam was produced from 18GHz ECRIS by using UF<sub>6</sub> and the <sup>238</sup>U ion was successfully accelerated by the accelerator complex which consists of the RFQ linear accelerator,RIKEN heavy ion linear accelerator（RILAC）and RIKEN ring cyclotron accelerator（RRC）.The typical beam intensity of<sup>238</sup>U<sup>14+</sup> was about 2pμA on faraday cup after analysing magnet.<sup>70</sup>Zn beam was still supplied for the new super-heavy element search experiment with insertion method.Intense beam of<sup>70</sup>Zn<sup>16+</sup> was produced for long term（～43 days）without vacuum break and remarkably low material consumption rate（～100μgr/h）.We already supplied Zn beam longer than 200 days for this experiment.<sup>48</sup>Ca ion was also produced by insertion method using<sup>48</sup>CaO rod for the nuclear physics experiment.In this contribution,we will present ion source parameter and techniques for production of each of the metal ions.
