Effects of Ion Beam Bombardment on the Crystalline Structure of Polymers: The Case of Pet+

1989 ◽  
Vol 157 ◽  
Author(s):  
R.M. Prppleo ◽  
M.R. Rrrujo ◽  
R.P. Livi
Keyword(s):  
Cross Sections ◽  
Ion Beam ◽  
Diffraction Peak ◽  
Large Decrease ◽  
Crystalline Morphology ◽  
Beam Irradiation ◽  
X Ray Diffraction ◽  
Ion Beam Irradiation ◽  
Scanning Calorimetry ◽  
X Ray

ABSTRACTWe discuss the amorphization process of semicrystalline and oriented PET (Polytethyleneterephtal ate)) thin toils by ion beam irradiation. P decrease in the bombarded samples melting point and enthalpy of fusion in the bombarded samples, as analysed by Differential Scanning Calorimetry (DSC), is associated with changes in the crystalline morphology and with an increase in the polymer disordered regions. Those facts are confirmed atso by a large decrease in the main X-ray diffraction peak amplitude as the tluence increases. P model of ion induced amorphization originally constructed for metals and semiconductors 11,23 was applied and cross-sections tor the process were obtained. The experimental data are well fitted using this model based on amorphization through the overlap of damage clusters, but an exclusive elastic collisions mechanism for the damage production cannot be inferred. As expected the electronic stopping mechanism also plays an important role in the polymer amorphization process.

Surface and Bulk Microstructural Modifications in Amorphous Carbon Films after Post-Growth Low Energy Ion Beam Irradiation

2000 ◽  
Vol 650 ◽  
Author(s):  
P. Patsalas ◽  
S. Logothetidis
Keyword(s):  
Amorphous Carbon ◽  
Amorphous Matrix ◽  
Ion Beam ◽  
Carbon Films ◽  
Low Energy ◽  
Beam Irradiation ◽  
X Ray Diffraction ◽  
Ion Beam Irradiation ◽  
Ion Energy ◽  
X Ray

ABSTRACTWe present the crystallization effects occurring in sputtered amorphous Carbon (a-C) thin films deposited on Si induced by post-growth low energy (0.5-1.5 keV) Ar+ ion beam irradiation (IBI). The a-C films after IBI have the form of an amorphous matrix with embedded crystalline regions. X-ray diffraction and Electron Microscopy measurements identified the crystalline phases of carbon and SiC. We study in detail the effects of ion energy and fluence on the crystallization process. It was found that low fluence (∼2×1016 ions/cm2) of ions with an optimum ion energy (∼1.5 keV) promoted the diamond formation. X-Ray Reflectivity (XRR) and Spectroscopic Ellipsometry were used to study the amorphous matrix. XRR discriminated the IBI induced surface and bulk effects through the density and the a-C surface roughness, showing surface smoothing to be more prominent for low energy IBI.

X-ray diffraction analysis of texture modification induced by ion beam irradiation in stainless steel films

2004 ◽  
Vol 228 (1-4) ◽  
pp. 151-157 ◽  
Author(s):  
P. Goudeau ◽  
J.L. Bechade ◽  
B. Boubeker ◽  
P.-O. Renault ◽  
A. Serrari ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Diffraction Analysis ◽  
Ion Beam ◽  
Beam Irradiation ◽  
X Ray Diffraction ◽  
Ion Beam Irradiation ◽  
X Ray ◽  
Texture Modification

Characteristics and Biodegradation Properties of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate)/Functionalized Graphene (PHBV/FGO) Blends

2016 ◽  
Vol 703 ◽  
pp. 290-294
Author(s):  
Yi Ning Hang ◽  
Kun Yan Wang ◽  
Bin Li
Keyword(s):  
Crystallization Behavior ◽  
Diffraction Peak ◽  
Thermal Barrier ◽  
Functionalized Graphene ◽  
Crystalline Morphology ◽  
X Ray Diffraction ◽  
Nucleation Agent ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Pom Analyses

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/functionalized graphene blends were prepared by solution blend method. The structure, thermal properties, thermal degradation and crystalline morphology were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetry (TG), and polarizing optical microscopy (POM) analyses. Experimental results indicated that FGO increase the intensity of diffraction peak. Small-sized PHBV spherulites were formed. FGO affects the crystallization behavior of PHBV as heterogeneous nucleation agent. FGO acts as an effective thermal barrier due to its large aspect ratio and thereby hinders the degradtion of PHBV.

Spontaneous formation of nanometer-scale self-organized structures in Ag-Cu alloys under irradiation

2000 ◽  
Vol 647 ◽  
Author(s):  
Raúl A. Enrique ◽  
Pascal Bellon
Keyword(s):  
Ion Irradiation ◽  
Ion Beam ◽  
Solute Concentration ◽  
Irradiation Temperature ◽  
Nanometer Scale ◽  
Beam Irradiation ◽  
X Ray Diffraction ◽  
Ion Beam Irradiation ◽  
Self Organized ◽  
The One

AbstractIon-beam irradiation can be used as a processing tool to synthesize metastable materials. A particular case is the preparation of solid solutions from immiscible alloys, which have been achieved for a whole range of systems. In this process, enhanced solute concentration is obtained through the local mixing induced by each irradiation event, which if occurring at a high enough frequency, can outweigh demixing by thermal diffusion. The resulting microstructure forms in far from equilibrium conditions, and theoretical results for these kind of driven alloys have shown that novel microstructures exhibiting self-organization can develop. To test these predictions, we prepare Ag-Cu multilayered thin films that we subject to 1 MeV Kr+-ion irradiation at temperatures ranging from room temperature to 225 °C, and characterize the specimens by x-ray diffraction, TEM and STEM. We observe two different phenomena occurring at different length scales: On the one hand, regardless of the irradiation temperature, grains grow under irradiation until reaching a size limited by film thickness (~200 nm). On the other hand, the distribution of species inside the grains is greatly affected by the irradiation temperature. At intermediate temperatures, a semi-coherent decomposition is observed at a nanometer scale. This nanometer-scale decomposition phenomenon appears as an evidence of patterning, and thus confirms on the possibility of using ion-beam irradiation as a route to synthesize nanostructured materials with novel magnetic and optical properties.

scholarly journals Effects of X-ray and carbon ion beam irradiation on membrane permeability and integrity in Saccharomyces cerevisiae cells

2015 ◽  
Vol 56 (2) ◽  
pp. 294-304 ◽  
Author(s):  
Guozhen Cao ◽  
Miaomiao Zhang ◽  
Jianshun Miao ◽  
Wenjian Li ◽  
Jufang Wang ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Membrane Permeability ◽  
Ion Beam ◽  
Beam Irradiation ◽  
Ion Beam Irradiation ◽  
Carbon Ion ◽  
X Ray ◽  
Carbon Ion Beam

Room Temperature Synthesis of Cu2O Nanospheres: Optical Properties and Thermal Behavior

2014 ◽  
Vol 21 (1) ◽  
pp. 108-119 ◽  
Author(s):  
Daniela Nunes ◽  
Lídia Santos ◽  
Paulo Duarte ◽  
Ana Pimentel ◽  
Joana V. Pinto ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Thermal Behavior ◽  
Room Temperature ◽  
Diffuse Reflectance Spectroscopy ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron

AbstractThe present work reports a simple and easy wet chemistry synthesis of cuprous oxide (Cu2O) nanospheres at room temperature without surfactants and using different precursors. Structural characterization was carried out by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy coupled with focused ion beam and energy-dispersive X-ray spectroscopy. The optical band gaps were determined from diffuse reflectance spectroscopy. The photoluminescence behavior of the as-synthesized nanospheres showed significant differences depending on the precursors used. The Cu2O nanospheres were constituted by aggregates of nanocrystals, in which an on/off emission behavior of each individual nanocrystal was identified during transmission electron microscopy observations. The thermal behavior of the Cu2O nanospheres was investigated with in situ X-ray diffraction and differential scanning calorimetry experiments. Remarkable structural differences were observed for the nanospheres annealed in air, which turned into hollow spherical structures surrounded by outsized nanocrystals.

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