Electronic and vibrational spectra of tourmaline – The impact of electron beam irradiation and heat treatment

This study aimed to develop novel Polylactic acid/ Halloysite (PLA/ HNTs) films which showed better properties when they were used for food packaging. They also displayed better mechanical, barrier, morphological and structural properties when the researchers analysed the impact of the electron beam irradiation on the nanomaterials. They prepared PLA-based nanocomposites containing 5 % w/w of HNTs using the solution casting process. These nanocomposites were further exposed to different ebeam doses (i.e., 0, 20, 40 and 60 kGy). The researchers assessed the effect of the electron beam irradiation on the various properties of the PLA. All the composites showed a homogenous dispersion and distribution of the HNTs in this PLA matrix. Results indicated that the nanocomposites showed better barrier properties in comparison to the neat PLA. Furthermore, the ebeam irradiation could increase the glass-transition temperature and lead to the development of more crosslinks, which increased the degradation temperature and hydrophilicity of the nanocomposites. In this study, the researchers showed that the PLA/HNTs films were effective materials that could be used for the electron beam processing of the pre-packed foods. The best effect was noted for the 20 kGy dosage which was used in the study.

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Influence of low-energy electron beam irradiation on defects in activated Mg-doped GaN

MRS Proceedings ◽

10.1557/proc-744-m10.7 ◽

2002 ◽

Vol 744 ◽

Cited By ~ 1

Author(s):

O. Gelhausen ◽

M. R. Phillips ◽

H. N. Klein ◽

E. M. Goldys

Keyword(s):

Electron Beam ◽

Electron Beam Irradiation ◽

Low Energy ◽

Energy Electron ◽

Beam Irradiation ◽

Hydrogen Atoms ◽

Acceptor Pair ◽

Low Energy Electron ◽

The Impact ◽

Mg Doped

ABSTRACTCL spectroscopy studies at varying temperatures and excitation power densities as well as depth-resolved CL imaging were conducted to investigate the impact of low energy electron beam irradiation (LEEBI) on native defects and residual impurities in metal-organic vapor phase epitaxy (MOVPE) grown Mg-doped p-type GaN. Due to the dissociation of (Mg-H)0 complexes, LEEBI significantly increases the (e,Mg0) emission (3.26 eV) at 300 K and substantially decreases the H-Mg donor-acceptor-pair (DAP) emission (3.27 eV) at 80 K. In-plane and depth-resolved CL imaging indicates that hydrogen dissociation results from electron-hole recombination at H-defect complexes rather than heating by the electron beam. The dissociated hydrogen atoms associate with nitrogen vacancies, forming a deeper donor, i.e. a (H-VN) complex. The corresponding deeper DAP emission with Mg centered at 3.1 eV is clearly observed between 160 and 220 K. Moreover, a broad yellow luminescence (YL) band centered at 2.2 eV is observed in MOVPE-grown Mg-doped GaN after LEEBI-treatment. It is suggested that a combination of LEEBI-induced Fermi-level downshift due to Mg-acceptor activation and simultaneous dissociation of gallium vacancy-impurity complexes, i.e. (VGa-H), is responsible for the observed YL.

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Ge nanoclusters in PECVD-deposited glass after heat treatment and electron-beam irradiation

Applied Physics B ◽

10.1007/s00340-007-2594-x ◽

2007 ◽

Vol 87 (2) ◽

pp. 327-331 ◽

Cited By ~ 3

Author(s):

H. Ou ◽

T.P. Rørdam ◽

K. Rottwitt ◽

F. Grumsen ◽

A. Horsewell ◽

...

Keyword(s):

Heat Treatment ◽

Electron Beam ◽

Electron Beam Irradiation ◽

Beam Irradiation

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Novel Organic Material Induced by Electron Beam Irradiation for Medical Application

Polymers ◽

10.3390/polym12020306 ◽

2020 ◽

Vol 12 (2) ◽

pp. 306 ◽

Cited By ~ 1

Author(s):

Adrian Barylski ◽

Krzysztof Aniołek ◽

Andrzej S. Swinarew ◽

Sławomir Kaptacz ◽

Jadwiga Gabor ◽

...

Keyword(s):

Electron Beam ◽

Electron Beam Irradiation ◽

Absorbed Dose ◽

Medical Application ◽

High Energy ◽

Polymer Chains ◽

Degree Of Crystallinity ◽

Beam Irradiation ◽

The Impact ◽

The Degree Of Crystallinity

This study analyzed the effects of irradiation of polytetrafluoroethylene (PTFE) containing 40% of bronze using an electron beam with energy of 10 MeV. Dosages from 26 to156 kGy (2.6–15.6 Mrad) were used. The impact of a high-energy electron beam on the thermal, spectrophotometric, mechanical, and tribological properties was determined, and the results were compared with those obtained for pure PTFE. Thermal properties studies showed that such irradiation caused changes in melting temperature Tm and crystallization temperature Tc, an increase in crystallization heat ∆Hc, and a large increase in crystallinity χc proportional to the absorbed dose for both polymers. The addition of bronze decreased the degree of crystallinity of PTFE by twofold. Infrared spectroscopy (FTIR) studies confirmed that the main phenomenon associated with electron beam irradiation was the photodegradation of the polymer chains for both PTFE containing bronze and pure PTFE. This had a direct effect on the increase in the degree of crystallinity observed in DSC studies. The use of a bronze additive could lead to energy dissipation over the additive particles. An increase in hardness H and Young’s modulus E was also observed. The addition of bronze and the irradiation with an electron beam improved of the operational properties of PTFE.

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Effect of Vacuum Heat Treatment on Electron-Beam-Irradiation-Cured Polycarbosilane Fibers

Journal of the American Ceramic Society ◽

10.1111/j.1151-2916.2001.tb00616.x ◽

2001 ◽

Vol 84 (1) ◽

pp. 111-116 ◽

Cited By ~ 6

Author(s):

Toshio Shimoo ◽

Masahiro Ito ◽

Kiyohito Okamura ◽

Michio Takeda

Keyword(s):

Heat Treatment ◽

Electron Beam ◽

Electron Beam Irradiation ◽

Vacuum Heat Treatment ◽

Beam Irradiation

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Impact of Electron Beam Irradiation on Thermoplastic Polyurethanes Unraveled by Thermal Field-Flow Fractionation

10.26434/chemrxiv.12918959.v1 ◽

2020 ◽

Author(s):

Martin Geisler ◽

Tuhin Subhra Pal ◽

Kerstin Arnhold ◽

Mikhail Malanin ◽

Michael Thomas Müller ◽

...

Keyword(s):

Electron Beam ◽

Size Exclusion Chromatography ◽

Electron Beam Irradiation ◽

Thermal Field ◽

Size Exclusion ◽

Field Flow Fractionation ◽

Beam Irradiation ◽

Exclusion Chromatography ◽

Flow Fractionation ◽

The Impact

The impact of electron beam irradiation on thermoplastic polyurethane material was studied for both an aliphatic and an aromatic polyurethane with equal amount of hard and soft segments. Irradiation doses up to 300 kGy at room temperature and at 100 °C were applied. Changes in chemical structure, molar mass and size were assessed using infrared spectroscopy, differential scanning calorimetry, size exclusion chromatography and thermal field flow fractionation. Material alterations were correlated with trends regarding to degradation, crosslinking or branching changes. Thereby, limits of characteri-zation by size exclusion chromatography are addressed and amended by thermal field-flow fractionation studies. In addition, a thermophoretic analysis has been carried out complementary to the portfolio of analytical methods applied in this work.

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Color change of tourmaline by heat treatment and electron beam irradiation: UV-Visible, EPR, and Mid-IR spectroscopic analyses

Journal of the Korean Physical Society ◽

10.3938/jkps.68.83 ◽

2016 ◽

Vol 68 (1) ◽

pp. 83-92 ◽

Cited By ~ 7

Author(s):

Apichate Maneewong ◽

Baek Seok Seong ◽

Eun Joo Shin ◽

Jeong Seog Kim ◽

Varavuth Kajornrith

Keyword(s):

Heat Treatment ◽

Electron Beam ◽

Electron Beam Irradiation ◽

Color Change ◽

Beam Irradiation ◽

Spectroscopic Analyses ◽

Uv Visible ◽

Ir Spectroscopic

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The Impact of Electron Beam Irradiation in Topaz Quality Enhancement

Journal of Physics Conference Series ◽

10.1088/1742-6596/1285/1/012022 ◽

2019 ◽

Vol 1285 ◽

pp. 012022

Author(s):

A Maneewong ◽

K Pangza ◽

T Charoennam ◽

N Thamrongsiripak ◽

N Jangsawang

Keyword(s):

Electron Beam ◽

Electron Beam Irradiation ◽

Quality Enhancement ◽

Beam Irradiation ◽

The Impact

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Effects of Thermal Stabilization and Electron Beam Irradiation on the Characteristics of Lignin Extracted from Black Liquor

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.381.64 ◽

2017 ◽

Vol 381 ◽

pp. 64-68

Author(s):

Dae Kyun Hwang ◽

Jeong Ho Kim ◽

Oh Hyeong Kwon ◽

Won Ho Park ◽

Dong Hwan Cho

Keyword(s):

Heat Treatment ◽

Electron Beam ◽

Industrial Waste ◽

Electron Beam Irradiation ◽

Treatment Process ◽

Black Liquor ◽

Thermal Stabilization ◽

Heat Treatment Process ◽

Beam Irradiation ◽

Stabilization Process

In the present work, lignin extracted from black liquor, which is industrial waste of pulp manufacturing. The extracted lignin was irradiated at various electron beam intensities from 100 to 1000 kGy. Also, the extracted lignin was thermally stabilized by heat treatment process. The characteristics of the stabilized and irradiated lignin materials were examined by means of TGA, ATR-FTIR, EA, and SEM. The ATR-FTIR result shows that both stabilized and irradiated lignin samples exhibit the decrease of characteristic absorption peaks, indicating the presence of guaiacyl and syringyl groups in the lignin structure. It reveals that the irradiation done to the ‘as-extracted’ lignin with appropriate electron beam intensity provides an efficiency as thermal stabilization of the lignin, suggesting that electron beam irradiation may apply directly to the extracted lignin, prior to carbonization the lignin without thermal stabilization process.

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