To simulate irradiation damage, argon ion was implanted in the Zircaloy-4 with the fluence ranging from 1 × 10^16 to 1 × 10^17 cm^-2, using accelerating implanter at an extraction voltage of 190 kV and liqui...To simulate irradiation damage, argon ion was implanted in the Zircaloy-4 with the fluence ranging from 1 × 10^16 to 1 × 10^17 cm^-2, using accelerating implanter at an extraction voltage of 190 kV and liquid nitrogen temperature. Then the influence of argon ion implantation on the aqueous corrosion behavior of Zircaloy-4 was studied. The valence states of elements in the surface layer of the samples were analyzed using X-ray photoelectron spectroscopy （XPS）. Transmission electron microscopy （TEM） was used to examine the microstructure of the argon-implanted samples. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted Zircaloy-4 in 1 mol/L HzSO4 solution. It is found that there appear bubbles on the surface of the samples when the argon fluence is 1 × 10^16 cm^-2. The microstructure of argon-implanted samples changes from amorphous to partial amorphous, then to polycrystalline, and again to amorphous. The corrosion resistance of implanted samples linearly declines with the increase of fluence approximately, which is attributed to the linear increase of the irradiation damage.展开更多
We measure the multiple ionization cross-section ratios Rk1 of Ar impacted by Cw＋ （q= 1-3） ions in the energy range of 20-500 keV/u. The measured ratios Rkl increase with the projectile energy at lower energies, an...We measure the multiple ionization cross-section ratios Rk1 of Ar impacted by Cw＋ （q= 1-3） ions in the energy range of 20-500 keV/u. The measured ratios Rkl increase with the projectile energy at lower energies, and reach the maximum at energies of 50-150 keV/u, then decrease for higher energies, We also use the classical over barrier ionization model to calculate the ratios Rk1, and the calculation results are in good agreement with the data, which suggest that the multiple ionization process is described by the sequential over-barrier ionization process,展开更多
Because of the lack of suitable animal models adapted to high vacuum stress in the low-energy ion implantation system, the bio-effects ion irradiation with an energy less than 50 keV on multi-cellular animal individua...Because of the lack of suitable animal models adapted to high vacuum stress in the low-energy ion implantation system, the bio-effects ion irradiation with an energy less than 50 keV on multi-cellular animal individuals have never been investigated so far. The nematode Caenorhabditis elegans has proved to be an excellent animal model used for the study of a broad spectrum of biological issues. The purpose of this work was to investigate the viability of this animal under ion irradiation. We studied the protection effects of glycerol and trehalose on the enhancement of nematodes＇ ability to bear the vacuum stress. The results showed that the survival of the nematodes was enhanced remarkably under long and slow desiccation, even without glycerol and trehalose. 159 glycerol showed a better anti-vacuum stress effect on the nematodes than trehalose did under short-time desiccation. Low-temperature pre-treatment or post-treatment of the samples had no obvious effect on the survival scored after argon ion irradiation. Moreover, little effect was induced by 15% glycerol- and vacuum-exposure on germ cell apoptosis, compared to the untreated control sample. It issuggested that such treatment would provide relatively low background for genotoxic evaluations with ion irradiation.展开更多
In this study, the polyacrylate intraocularr lens is irradiated by argon ion which can produce free radicals. In order to obtain better hydrophilic and lower platelets adhesion, monomer vinyl pyrrolidone (NVP) is graf...In this study, the polyacrylate intraocularr lens is irradiated by argon ion which can produce free radicals. In order to obtain better hydrophilic and lower platelets adhesion, monomer vinyl pyrrolidone (NVP) is grafted onto the hydrophobic polyacrylate intraocular lens surface in a certain reaction conditions. Specific changes in intraocular lens are detected by static contact angle (CA), scanning electron microscope (SEM) and light transmittance. The results show that this surface modification can greatly improve its hydrophilic character and surface formation.展开更多
基金the National Nature Science Foundation of China(No.50501011)the Postdoctoral Research Foundation of China(No.2005037079)
文摘To simulate irradiation damage, argon ion was implanted in the Zircaloy-4 with the fluence ranging from 1 × 10^16 to 1 × 10^17 cm^-2, using accelerating implanter at an extraction voltage of 190 kV and liquid nitrogen temperature. Then the influence of argon ion implantation on the aqueous corrosion behavior of Zircaloy-4 was studied. The valence states of elements in the surface layer of the samples were analyzed using X-ray photoelectron spectroscopy （XPS）. Transmission electron microscopy （TEM） was used to examine the microstructure of the argon-implanted samples. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted Zircaloy-4 in 1 mol/L HzSO4 solution. It is found that there appear bubbles on the surface of the samples when the argon fluence is 1 × 10^16 cm^-2. The microstructure of argon-implanted samples changes from amorphous to partial amorphous, then to polycrystalline, and again to amorphous. The corrosion resistance of implanted samples linearly declines with the increase of fluence approximately, which is attributed to the linear increase of the irradiation damage.
文摘We measure the multiple ionization cross-section ratios Rk1 of Ar impacted by Cw＋ （q= 1-3） ions in the energy range of 20-500 keV/u. The measured ratios Rkl increase with the projectile energy at lower energies, and reach the maximum at energies of 50-150 keV/u, then decrease for higher energies, We also use the classical over barrier ionization model to calculate the ratios Rk1, and the calculation results are in good agreement with the data, which suggest that the multiple ionization process is described by the sequential over-barrier ionization process,
文摘Because of the lack of suitable animal models adapted to high vacuum stress in the low-energy ion implantation system, the bio-effects ion irradiation with an energy less than 50 keV on multi-cellular animal individuals have never been investigated so far. The nematode Caenorhabditis elegans has proved to be an excellent animal model used for the study of a broad spectrum of biological issues. The purpose of this work was to investigate the viability of this animal under ion irradiation. We studied the protection effects of glycerol and trehalose on the enhancement of nematodes＇ ability to bear the vacuum stress. The results showed that the survival of the nematodes was enhanced remarkably under long and slow desiccation, even without glycerol and trehalose. 159 glycerol showed a better anti-vacuum stress effect on the nematodes than trehalose did under short-time desiccation. Low-temperature pre-treatment or post-treatment of the samples had no obvious effect on the survival scored after argon ion irradiation. Moreover, little effect was induced by 15% glycerol- and vacuum-exposure on germ cell apoptosis, compared to the untreated control sample. It issuggested that such treatment would provide relatively low background for genotoxic evaluations with ion irradiation.
基金National Natural Science of Foundation of Chinagrant number:81070716
文摘In this study, the polyacrylate intraocularr lens is irradiated by argon ion which can produce free radicals. In order to obtain better hydrophilic and lower platelets adhesion, monomer vinyl pyrrolidone (NVP) is grafted onto the hydrophobic polyacrylate intraocular lens surface in a certain reaction conditions. Specific changes in intraocular lens are detected by static contact angle (CA), scanning electron microscope (SEM) and light transmittance. The results show that this surface modification can greatly improve its hydrophilic character and surface formation.
