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.

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.

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.

Positive-Tone Polymer Images by Surface Modification in Ion Beam Exposures

1985 ◽  
Vol 45 ◽  
Author(s):  
Hiroyuki Hiraoka
Keyword(s):  
Carboxylic Acid ◽  
Energy Deposition ◽  
Ion Beam ◽  
High Energy ◽  
Polymer Surfaces ◽  
High Energy Radiation ◽  
Carboxylic Acid Groups ◽  
Surface Areas ◽  
Novolac Resins ◽  
Low Energy Electron

ABSTRACTUnder exposures of high energy radiation in vacuum, decarboxylation takes place efficiently on polymer surfaces having carboxylic acid groups. Low energy electron and ion beams are particularly efficient in these chemical reactions on the surfaces because their energy deposition is limited to very shallow depths. The surface areas exposed to the radiation have properties similar to hydrocarbons after decarboxylation, resulting in non-reactions in gas phase silylation, while unexposed areas undergo silylation readily due to the presence of reactive acid groups. The non-silylated areas etch faster in oxygen reactive ion etchings, giving rise to positive tone polymer images. Polymers like poly(methacrylic acid), poly(acrylic acid), and their copolymers have been used. Other polymers like poly(styrene), poly(chloromethylstyrene), and Novolac resins can also be used, because these polymers readily undergo photo-oxidation under uv-irradiation in air, generating carboxylic acid groups on their surfaces.

Ion Beam Assisted Quantum well Intermixing

1995 ◽  
Vol 396 ◽  
Author(s):  
R. D. Goldberg ◽  
I. V. Mitchell ◽  
S. Charbonneau ◽  
P. Poole ◽  
E. S. Koteles ◽  
...  
Keyword(s):  
Quantum Well ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Multiple Quantum Well ◽  
High Energy ◽  
Multiple Quantum ◽  
Active Components ◽  
Quantum Well Structures ◽  
Ion Species ◽  
Made In

AbstractSignificant progress has been made in the past year in the use of high energy (MeV) ion irradiation to tune the bandgap and therefore emission wavelengths of single and multiple quantum well structures. These shifts are attributable to compositional mixing across the well and barrier layer interfaces, a process that is driven by the vacancy flux, released during the anneal stage, from radiation defects. We present data from a series of measurements in both GaAs- and InP-based QW structures to demonstrate the importance of the implantation parameters chosen (ion species, energy, flux, fluence and implant temperature). The dramatic difference in the response of these two systems with regard to the implant depth is believed to be associated with the very different diffusivities of the Gp III site vacancies. Prospects for implementing the irradiation approach as a spatially selective, planar process in integrated optoelectronic circuitry look very attractive and are illustrated for both passive and active components by reference to recent results from tuned wavelength lasers.

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.

THE USE OF MARKERS AND NUCLEAR MICROANALYSIS TO MONITOR ATOMIC TRANSPORT INDUCED BY ION BOMBARDMENT IN SOLIDS

1995 ◽  
Vol 09 (03n04) ◽  
pp. 163-186 ◽  
Author(s):  
LIONEL THOMÉ ◽  
FRÉDÉRICO GARRIDO
Keyword(s):  
Ion Irradiation ◽  
Ion Beam ◽  
Ion Bombardment ◽  
High Energy ◽  
Near Surface ◽  
Energetic Ions ◽  
Nuclear Microanalysis ◽  
Atomic Transport ◽  
Very High Energy ◽  
Marker Profile

This paper describes an original methodology developed to study the atomic transport in a solid target bombarded with energetic ions. This methodology is based on the use of heavy marker atoms introduced in the near-surface layer of the investigated target and the analysis via nuclear microanalysis techniques of the modifications of the marker profile due to ion bombardment. Results obtained in the case of low- or medium-energy (<10 keV/u ) ion irradiation, leading to the well-known ion-beam-mixing process induced by nuclear elastic collisions, are reported in the first part. The second part deals with the less-investigated case of very-high-energy (>1 MeV/u ) ion irradiation, where a dramatic plastic deformation mechanism induced by electronic excitation has been recently discovered.

scholarly journals Stability of Uranium Silicides During High Energy Ion Irradiation

1991 ◽  
Vol 235 ◽  
Author(s):  
R. C. Birtcher ◽  
L. M. Wang
Keyword(s):  
Ion Irradiation ◽  
Ion Beam ◽  
Amorphous State ◽  
Temperature Limit ◽  
High Energy ◽  
Grain Structure ◽  
Twin Structure ◽  
Fine Grain ◽  
Transmission Electron

ABSTRACTChanges induced by 1.5 MeV Kr ion irradiation of both U3Si and U3Si2 have been followed by in situ transmission electron microcopy. When irradiated at sufficiently low temperatures, both alloys transform from the crystalline to the amorphous state. When irradiated at temperatures above the temperature limit for ion-beam amorphization, both compounds disorder, with the Martensite twin structure in U3Si disappearing from view in TEM. Prolonged irradiation of the disordered crystalline phases results in nucleation of small crystallites within the initially large crystal grains. The new crystallites increase in number during continued irradiation until a fine grain structure is formed. Electron diffraction yields a powder-like diffraction pattern that indicates a random alignment of the small crystallites. During a second irradiation at lower temperatures, the small crystallizes retard amorphization. After 2 dpa at high temperatures, the amorphization dose is increased by over twenty times compared to that of initially unirradiated material.

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.

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