分别采用生物辐照仪和模拟铀矿室作为γ辐照源,研究了低剂量和超低剂量γ照射对青海弧菌Q67发光强度和光密度(OD_(600))的影响。实验结果表明,青海弧菌Q67在5.5 c Gy/min照射剂量率、不同累积照射剂量γ射线照射下,在一定累积照射剂量...分别采用生物辐照仪和模拟铀矿室作为γ辐照源,研究了低剂量和超低剂量γ照射对青海弧菌Q67发光强度和光密度(OD_(600))的影响。实验结果表明,青海弧菌Q67在5.5 c Gy/min照射剂量率、不同累积照射剂量γ射线照射下,在一定累积照射剂量范围内,发光强度的抑制率无显著差异,当累积照射剂量超过该范围的累积照射剂量的阈值后,发光强度抑制率与累积照射剂量呈正相关。青海弧菌Q67在320 m Gy累积照射剂量,5.5、14和51 c Gy/min 3个不同照射剂量率γ射线照射下,发光强度在低照射剂量率、长时间的γ射线照射条件下抑制率更大。青海弧菌Q67在长时间超低γ射线照射剂量率的条件下,菌液的OD_(600)值的抑制率在24 h达到最大值,此后逐渐降低,其中30和120μGy/h两组剂量率照射下,青海弧菌Q67菌体数呈现低剂量兴奋效应。通过测定低剂量和超低剂量γ射线照射对青海弧菌Q67的发光强度和菌液OD_(600)值的抑制率,可反映一定剂量范围内的γ射线照射对青海孤菌Q67的综合毒性作用。青海孤菌Q67对γ射线具有较好的敏感性,可用作低剂量γ射线毒性评价的生物材料。展开更多
A HeHPC (Helium high pressure chamber) filled up with pure gaseous helium at initial pressure about 1.1 bar was irradiated by braking γ-rays of 10 MeV threshold energy during 1.0 × 10^5 s at the electron beam ...A HeHPC (Helium high pressure chamber) filled up with pure gaseous helium at initial pressure about 1.1 bar was irradiated by braking γ-rays of 10 MeV threshold energy during 1.0 × 10^5 s at the electron beam current 22 - 24 μA. After irradiation, the residual pressure inside was equal to 430 bar. Synthesized foils of black color and other multiple objects were found inside the HeHPC mainly at the entrance window for γ-rays made from beryllium bronze as a plug of beryllium bronze HPC, at the inner surfaces of the reaction chamber made of high purity copper and at the copper collector. The element analysis, using SEM (Scanning electron microscopy) and MPRA (Microprobe roentgen analysis), allowed us to establish that the foils consist predominantly of carbon and the smaller quantities of other elements from carbon to iron. An explanation for the observed elements is suggested on the basis of helium fusion reactions under the action of y-rays with the reactions taking place in giant stars (thermally activated). The possible mechanism after 3α reaction is nα reactions and under barrier reactions. A second experiment with initial pressure of 3.05 kbar (with pressure drop by about 65 bar - after almost the same procedure of y-rays irradiation and with fully beryl bronze environment) suggests another possible nuclear reactions - He(Be, p)C, He(C, γ)O, and so on. The developed approach agrees well with a series of studies carried out by the authors where dense hydrogen and deuterium gases are acted on by γ-rays in the presence or absence of metals in the reaction chambers.展开更多
文摘分别采用生物辐照仪和模拟铀矿室作为γ辐照源,研究了低剂量和超低剂量γ照射对青海弧菌Q67发光强度和光密度(OD_(600))的影响。实验结果表明,青海弧菌Q67在5.5 c Gy/min照射剂量率、不同累积照射剂量γ射线照射下,在一定累积照射剂量范围内,发光强度的抑制率无显著差异,当累积照射剂量超过该范围的累积照射剂量的阈值后,发光强度抑制率与累积照射剂量呈正相关。青海弧菌Q67在320 m Gy累积照射剂量,5.5、14和51 c Gy/min 3个不同照射剂量率γ射线照射下,发光强度在低照射剂量率、长时间的γ射线照射条件下抑制率更大。青海弧菌Q67在长时间超低γ射线照射剂量率的条件下,菌液的OD_(600)值的抑制率在24 h达到最大值,此后逐渐降低,其中30和120μGy/h两组剂量率照射下,青海弧菌Q67菌体数呈现低剂量兴奋效应。通过测定低剂量和超低剂量γ射线照射对青海弧菌Q67的发光强度和菌液OD_(600)值的抑制率,可反映一定剂量范围内的γ射线照射对青海孤菌Q67的综合毒性作用。青海孤菌Q67对γ射线具有较好的敏感性,可用作低剂量γ射线毒性评价的生物材料。
文摘A HeHPC (Helium high pressure chamber) filled up with pure gaseous helium at initial pressure about 1.1 bar was irradiated by braking γ-rays of 10 MeV threshold energy during 1.0 × 10^5 s at the electron beam current 22 - 24 μA. After irradiation, the residual pressure inside was equal to 430 bar. Synthesized foils of black color and other multiple objects were found inside the HeHPC mainly at the entrance window for γ-rays made from beryllium bronze as a plug of beryllium bronze HPC, at the inner surfaces of the reaction chamber made of high purity copper and at the copper collector. The element analysis, using SEM (Scanning electron microscopy) and MPRA (Microprobe roentgen analysis), allowed us to establish that the foils consist predominantly of carbon and the smaller quantities of other elements from carbon to iron. An explanation for the observed elements is suggested on the basis of helium fusion reactions under the action of y-rays with the reactions taking place in giant stars (thermally activated). The possible mechanism after 3α reaction is nα reactions and under barrier reactions. A second experiment with initial pressure of 3.05 kbar (with pressure drop by about 65 bar - after almost the same procedure of y-rays irradiation and with fully beryl bronze environment) suggests another possible nuclear reactions - He(Be, p)C, He(C, γ)O, and so on. The developed approach agrees well with a series of studies carried out by the authors where dense hydrogen and deuterium gases are acted on by γ-rays in the presence or absence of metals in the reaction chambers.