Effects of High-Energy Carbon Ion Irradiation on Isatis Indigotica Fort

2011 ◽  
Vol 317-319 ◽  
pp. 2056-2062 ◽  
Author(s):  
Guang Liang Shi ◽  
Xue Hong Wang ◽  
Kai Guo ◽  
Zhao Zhou Li ◽  
Xiao Yan Hu ◽  
...  
Keyword(s):  
Soluble Protein ◽  
Selective Breeding ◽  
Ion Irradiation ◽  
Ion Beam ◽  
High Energy ◽  
Total Soluble Protein ◽  
High Dose ◽  
Isatis Indigotica ◽  
Carbon Ion ◽  
Different Doses

The aim of this study was to provide a theoretical basis for a high-energy carbon ion irradiation process for inducing mutations for selective breeding in Isatis indigotica Fort. The experiments were designed to evaluate the effects of different doses of high-energy 12C6+ ions (10-140 Gy) on physiological changes in I. indigotica seedlings. Dry seeds of I. indigotica were irradiated using different doses of 270 MeV energy 12C6+ ion beam, and the response of the subsequent seedlings was monitored using well-established indexes of physiological characteristics. Results showed that optimum results were achieved with a high-dose 12C6+ ion beam at 35 Gy where the activities of superoxide dismutase (SOD) and catalase (CAT) were enhanced. However, excessive irradiation reduced the activities of SOD and CAT. As the dose increased, the activity of peroxidase increased initially and then decreased compared with controls that were not irradiated (0 Gy). The content of malondialdehyde first decreased and then increased with the treatment. Total soluble protein content initially increased and then decreased with increasing doses of radiation; the proline content improved sharply compared to the control. The results of this study suggest that that a low dose of 12C6+ ion beam could enhance the activities of protective enzymes and the levels of proline and soluble protein, and that a dose range of 35–60 Gy is likely to be optimum for inducing useful mutations in I. indigotica for a stable selective breeding program.

Radiation-Induced Nanostructures in an Iron Phosphate Glass

2003 ◽  
Vol 792 ◽  
Author(s):  
K. Sun ◽  
T. Ding ◽  
L.M. Wang ◽  
R.C. Ewing
Keyword(s):  
Phosphate Glass ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Dose Range ◽  
Iron Phosphate ◽  
High Energy ◽  
High Dose ◽  
Beam Irradiation ◽  
Ion Beam Irradiation ◽  
Feo Nanoparticles

ABSTRACTElectron and ion irradiation-induced nanostructures in an iron phosphate glass with a composition of 45 mol%Fe2O3-55 mol%P2O5 have been characterized by advanced electron microbeam techniques. Analysis by energy-filtered transmission electron microscopy indicated that Fe-rich and P-rich nanophases were formed when the glass was irradiated under a broad (with a diameter of 1.2μm) electron beam [give the dose range]. Phase separation developed with the increase in electron dose (from 1.0×1026e/m2 to 4.8×1026e/m2) as a result of the formation of an Fe-rich phase and pure P-phase. The formation of the Fe-rich and the P-phases are thought to be due to mainly ionization process. Under a low energy ion beam irradiation, Fe/FeO nanoparticles were formed, as confirmed by selected-area electron diffraction analysis. However, no nanoparticles were observed under a high-energy high-dose ion irradiation. The ion beam-irradiation results suggest that the formation of the Fe/FeO nanoparticles was due to preferential sputtering during ion irradiation and that the nanoparticles lie within the surface layers of the glass.

Effects of Carbon-Ion Irradiation-Energies on the Molecular Beam Epitaxy of GaAs and Ingaas

1995 ◽  
Vol 388 ◽  
Author(s):  
Y. Makita ◽  
T. Iida ◽  
T. Shima ◽  
S. Kimura ◽  
A. Obara ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Current Density ◽  
Molecular Beam ◽  
Ion Irradiation ◽  
Hole Concentration ◽  
Ion Beam ◽  
High Energy ◽  
Beam Current Density ◽  
Carbon Ion ◽  
Activation Rate

AbstractCarbon ion (C+) irradiation during molecular beam epitaxy (MBE) growth of GaAs/GaAs and in0.53.Ga0.47As/InP layers was carried out using CIBMBE (combined ion beam and molecular beam epitaxy) method as a function of wide acceleration energy (Ea=30 eV-30 keV) at a constant ion beam current density. Judging from the monitored current density and the net hole concentration (INA-ND|) obtained from Hall effect measurements, activation rate as high as 88% was achieved for as-grown GaAs layers by C+ ion irradiation of Ea=~170eV. It was revealed that by annealing at 800°C, a slight enhancement (~ 10%) of INA-ND| is practiced for Ea <~ 130eV but a significant increase of INA-ND| is realized for Ea>~lkeV. IN in0.53Ga0.47As/InP layers with increasing Ea, a type conversion of electric conduction from n to p was found to occur at Ea= ~70~100eV. these observations describe that Ea plays a vital role to determine the location of incorporated electrical and optical active impurities in GaAs and inGaAs. Further for comparison, C+-implanted GaAs layers were prepared by high-energy (400 keV) ion-implantation as a function of substrate temperature (T1=RT-600 °C). For C dose concentration of lxl018cm-3\ the highest activation rate of ~20 % was obtained at T1=~150 °C. This result states that CIBMBE method is a superior doping method in view of activation rate of introduced dopants and the formation of damage-free ion-irradiated layers.

Electron and ion irradiation-induced dissolution of mechanical twins in the intermetalic U3Si: An in situ HVEM study

1989 ◽  
Vol 47 ◽  
pp. 652-653
Author(s):  
Charles W. Allen ◽  
Robert C. Birtcher
Keyword(s):  
Elevated Temperatures ◽  
Ion Irradiation ◽  
Ion Beam ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Heavy Ion ◽  
High Energy ◽  
Mechanical Twinning ◽  
In Situ Experiments

The uranium silicides, including U3Si, are under study as candidate low enrichment nuclear fuels. Ion beam simulations of the in-reactor behavior of such materials are performed because a similar damage structure can be produced in hours by energetic heavy ions which requires years in actual reactor tests. This contribution treats one aspect of the microstructural behavior of U3Si under high energy electron irradiation and low dose energetic heavy ion irradiation and is based on in situ experiments, performed at the HVEM-Tandem User Facility at Argonne National Laboratory. This Facility interfaces a 2 MV Tandem ion accelerator and a 0.6 MV ion implanter to a 1.2 MeV AEI high voltage electron microscope, which allows a wide variety of in situ ion beam experiments to be performed with simultaneous irradiation and electron microscopy or diffraction.At elevated temperatures, U3Si exhibits the ordered AuCu3 structure. On cooling below 1058 K, the intermetallic transforms, evidently martensitically, to a body-centered tetragonal structure (alternatively, the structure may be described as face-centered tetragonal, which would be fcc except for a 1 pet tetragonal distortion). Mechanical twinning accompanies the transformation; however, diferences between electron diffraction patterns from twinned and non-twinned martensite plates could not be distinguished.

scholarly journals Hydrophilicity Improvement of Polymer Surfaces Induced by Simultaneous Nuclear Transmutation and Oxidation Effects Using High-Energy and Low-Fluence Helium Ion Beam Irradiation

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2770
Author(s):  
Jung Woo Kim ◽  
Seung Hwa Yoo ◽  
Young Bae Kong ◽  
Sung Oh Cho ◽  
Eun Je Lee
Keyword(s):  
Surface Texture ◽  
Ion Irradiation ◽  
Ion Beam ◽  
High Energy ◽  
Contact Angles ◽  
Polymer Chains ◽  
Polymer Surfaces ◽  
Water Contact ◽  
Chemical Structures ◽  
Nuclear Transmutation

Two commodity polymers, polystyrene (PS) and high-density polyethylene (HDPE), were irradiated by high-energy He ion beams at low fluence to examine the wettability changes at different fluences. The water contact angles of the PS and HDPE surfaces were reduced from 78.3° to 46.7° and 81.5° to 58.5°, respectively, upon increasing the fluence from 0 to 1 × 1013 He2+/cm2 for irradiation durations ≤4 min. Surface analyses were performed to investigate these wettability changes. Surface texture evaluations via scanning electron and atomic force microscopies indicated non-remarkable changes by irradiation. However, the chemical structures of the irradiated polymer surfaces were notable. The high-energy He ions induced nuclear transmutation of C to N, leading to C–N bond formation in the polymer chains. Further, C–O and C=O bonds were formed during irradiation in air because of polymer oxidation. Finally, amide and ester groups were generated by irradiation. These polar groups improved hydrophilicity by increasing surface energies. Experiments with other polymers can further elucidate the correlation between polymer structure and surface wettability changes due to high-energy low-fluence He ion irradiation. This method can realize simple and effective utilization of commercial cyclotrons to tailor polymer surfaces without compromising surface texture and mechanical integrity.

Effects of gamma-ray and high energy carbon ion irradiation on swimming velocity of Euglena gracilis

2002 ◽  
Vol 30 (4) ◽  
pp. 1023-1030 ◽  
Author(s):  
T. Sakashita ◽  
M. Doi ◽  
H. Yasuda ◽  
S. Fuma ◽  
D.-P. Häder
Keyword(s):  
Euglena Gracilis ◽  
Gamma Ray ◽  
Ion Irradiation ◽  
High Energy ◽  
Swimming Velocity ◽  
Carbon Ion

Evolution of Ion Beam Synthesized Au Nanoclusters in SiO2 under Ion Irradiation

2000 ◽  
Vol 647 ◽  
Author(s):  
Bernd Schmidt ◽  
Karl-Heinz Heinig ◽  
Arndt Mücklich
Keyword(s):  
Size Distribution ◽  
Ostwald Ripening ◽  
Ion Irradiation ◽  
Kinetic Monte Carlo ◽  
Ion Beam ◽  
Thick Layer ◽  
High Energy ◽  
Au Nanoclusters ◽  
Post Irradiation ◽  
Mean Size

AbstractThe evolution of the mean size and the size distribution of Au nanoclusters (NCs) under high-energy ion irradiation has been studied. Au NCs were synthesized in a 480 nm thick SiO2 layer by 330 keV Au+ implantation and subsequent annealing at T = 1000 °C for 1h in dry O2. XTEM images show a 70 nm thick layer of Au NCs, being centered at the projected ion range Rp(330keV) = 100 nm, having a mean NC size of 5 nm at Rp, and resembling the broad Lifshiz-Slyozov-Wagner (LSW) size distribution of diffusion controlled Ostwald ripening. Post-irradiation of the Au NCs by 4.5 MeV gold ions was used in order to tailor their size and size distribution. The high-energy Au+ irradiations were performed at 190...210 °C with a fluence of (0.5...1.0)×1016 cm-2. By the post-irradiation no gold was deposited into the SiO2 layer, the Au+ ions come to rest in the (001)Si substrate at Rp(4.5MeV) = 1 [.proportional]m. XTEM images of the post-irradiated Au NCs show a strong decrease of their mean size as well as the width of their size distribution. The observed NC evolution under ion irradiation agrees with recent theoretical predictions and kinetic Monte-Carlo simulations.

Comparison of Conductivity Produced in Polymers and Carbon Films by Pyrolysis and High Energy Ion Irradiation

1983 ◽  
Vol 27 ◽  
Author(s):  
T. Venkatesan ◽  
R. C. Dynes ◽  
B. Wilkens ◽  
A. E. White ◽  
J. M. Gibson ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Carbon Film ◽  
Physical Nature ◽  
High Energy ◽  
Carbon Films ◽  
Chemical Degradation ◽  
Beam Irradiation ◽  
Ion Beam Irradiation

ABSTRACTThe electrical properties of pyrolyzed polymers have been studied recently.1,2 It has been shown that organic, polymeric3 and non-polymeric4 films can be made conductive (ρ ~ 10−3Ωcm) by ion beam irradiation. Common to all of the films was the presence of carbon as a constituent element and both pyrolysis and ion beam irradiation3 was shown to increase the relative carbon content of the films. The ion beam irradiated organic films 3,4 exhibited a temperature dependence of their resistivity of the form ρ(T) = ρ∞e−(TЛ)*, where ρ is the ion-induced resistivity, ρ∞ and T0 are constants and T is the temperature. At very high doses of irradiation (1017cm−2Ar+@ 2MeV) the film resistivity was temperature independent. Very similar transport properties were observed in the pyrolyzed polymers1 as well, though the lowest resistivities achieved were higher than the resistivity values observed in the ion irradiated3 polymer films. In both the pyrolysis and ion-irradiation experiments the temperature dependence has been explained by a model due to Sheng and Abeles,5 which involves charge transport by hopping between conducting islands embedded in an insulating matrix. Such striking similarities between two distinctly different modes of energy deposition in the films, prompted us to compare the effects of pyrolysis and ion irradiation in different carbon containing films. We compared both a polymer (HPR-204°) and a film of electron beam evaporated carbon film. While in the former case one would observe chemical degradation as well as structural modification, by studying pure carbon films the physical nature of the processes could be clarified. We report metallic carrier densities in both films and evidence for significant structural rearrangement. We conclude that pyrolysis and ion beam irradiation have similar effects on both polymer and carbon films.

Radiation-induced disordering and amorphization—An in situ HVEM study of uranium silicide with comparison to natural processes in zirconolite

1990 ◽  
Vol 48 (4) ◽  
pp. 534-535
Author(s):  
R. C. Birtcher ◽  
L. M. Wang ◽  
C. W. Allen ◽  
R. C. Ewing
Keyword(s):  
Electron Irradiation ◽  
Ion Irradiation ◽  
Ion Beam ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Heavy Ion ◽  
High Energy ◽  
In Situ Tem ◽  
In Situ Experiments

We present here results of in situ TEM diffraction observations of the response of U3Si and U3Si2 when subjected to 1 MeV electron irradiation or to 1.5 MeV Kr ion irradiation, and observations of damage occuring in natural zirconolite. High energy electron irradiation or energetic heavy ion irradiation were performed in situ at the HVEM-Tandem User Facility at Argonne National Laboratory. In this Facility, a 2 MV Tandem ion accelerator and a 0.6 MV ion implanter have been interfaced to a 1.2 MeV AEI high voltage electron microscope. This allows a wide variety of in situ experiments to be performed with simultaneous ion irradiation and conventional transmission electron microscopy. During the electron irradiation, the electron beam was focused to a diameter of about 2 μ.m at the specimen thin area. The ion beam was approximately 2 mm in diameter and was uniform over the entire specimen. With the specimen mounted in a heating holder, the temperature increase indicated by the furnace thermocouple during the ion irradiation was typically 8 °K.

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