Sheep Wool Humidity under Electron Irradiation Affects Wool Sorptivity towards Co(II) Ions

The effect of humidity on sheep wool during irradiation by an accelerated electron beam was examined. Each of the samples with 10%, 53%, and 97% relative humidity (RH) absorbed a dose of 0, 109, and 257 kGy, respectively. After being freely kept in common laboratory conditions, the samples were subjected to batch Co(II) sorption experiments monitored with VIS spectrometry for different lapses from electron beam exposure. Along with the sorption, FTIR spectral analysis of the wool samples was conducted for cysteic acid and cystine monoxide, and later, the examination was completed, with pH measuring 0.05 molar KCl extract from the wool samples. Besides a relationship to the absorbed dose and lapse, the sorptivity results showed considerable dependence on wool humidity under exposure. When humidity was deficient (10% RH), the sorptivity was lower due to limited transformation of cystine monoxide to cysteic acid. The wool pre-conditioned at 53% RH, which is the humidity close to common environmental conditions, demonstrated the best Co(II) sorptivity in any case. This finding enables the elimination of pre-exposure wool conditioning in practice. Under excessive humidity of 97% RH and enough high dose of 257 kGy, radiolysis of water occurred, deteriorating the sorptivity. Each wool humidity, dose, and lapse showed a particular scenario. The time and humidity variations in the sorptivity for the non-irradiated sample were a little surprising; despite the absence of electron irradiation, relevant results indicated a strong sensitivity to pre-condition humidity and lapse from the start of the monitoring.

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Clinical implementation of total skin electron irradiation treatment with a 6 MeV electron beam in high-dose total skin electron mode

10.1063/1.4955387 ◽

2016 ◽

Author(s):

J. F. Lucero ◽

J. I. Rojas

Keyword(s):

Electron Beam ◽

Electron Irradiation ◽

High Dose ◽

Clinical Implementation ◽

Irradiation Treatment ◽

Electron Mode

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Some Properties of Electron Beam-Irradiated Sheep Wool Linked to Cr(III) Sorption

Molecules ◽

10.3390/molecules24234401 ◽

2019 ◽

Vol 24 (23) ◽

pp. 4401 ◽

Cited By ~ 2

Author(s):

Jana Braniša ◽

Angela Kleinová ◽

Klaudia Jomová ◽

Radka Malá ◽

Volodymyr Morgunov ◽

...

Keyword(s):

Electron Beam ◽

Absorbed Dose ◽

Concentrated Solutions ◽

Octahedral Structure ◽

Fiber Volume ◽

Optimized Conditions ◽

Higher Doses ◽

Charge Point ◽

Sheep Wool

We examined the characteristics of an electron beam irradiated wool with an absorbed dose of (21–410) kGy in comparison with natural wool with respect to the determination of the isoelectric point (IEP), zero charge point (ZCP), mechanism of Cr(III) sorption from higher concentrated solutions, and the modelling of the wool-Cr(III) interaction. The data of ZPC and IEP differed between natural and irradiated samples. Increasing the dose shifted the pH of ZPC from 6.85 for natural wool to 6.20 for the highest dosed wool, while the natural wool IEP moved very little, from pH = 3.35 to 3.40 for all of the irradiated samples. The sorption experiments were performed in a pH bath set at 3.40, and the determination of the residual Cr(III) in the bath was performed by VIS spectrometry under optimized conditions. The resulting sorptivity showed a monotonically rising trend with increasing Cr(III) concentration in the bath. Lower doses, unlike higher doses, showed better sorptivity than the natural wool. FTIR data indicated the formation of complex chromite salts of carboxylates and cysteinates. Crosslinks via ligands coming from different keratin chains were predicted, preferably on the surface of the fibers, but to a degree that did not yet inhibit the diffusion of Cr(III)-cations into the fiber volume. We also present a concept of a complex octahedral structure.

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Nanoparticles synthesis by electron beam radiolysis

Open Chemistry ◽

10.2478/s11532-014-0502-x ◽

2014 ◽

Vol 12 (7) ◽

pp. 774-781 ◽

Cited By ~ 5

Author(s):

Ioan Călinescu ◽

Diana Martin ◽

Daniel Ighigeanu ◽

Adina Gavrila ◽

Adrian Trifan ◽

...

Keyword(s):

Silver Nanoparticles ◽

Electron Beam ◽

Chemical Reduction ◽

Absorbed Dose ◽

Reduction Process ◽

High Dose Rate ◽

High Dose ◽

Experimental Conditions ◽

Dose Rates ◽

Absorbed Dose Rates

AbstractElectron beam (EB) irradiation is a useful method to generate stable silver nanoparticles without the interference of inherent impurities generated from chemical reactions. Our experiments were carried out using linear electron beam accelerators with two different EB absorbed dose rates: 2 kGy min−1 and 7–8 kGy s−1, and with different absorbed dose levels. The optimum conditions for silver nanoparticles (AgNPs) generation by radiolysis, or by radiolysis combined with chemical reduction, were established. In order to obtain a good yield for AgNPs synthesized by radiolysis, a high dose rate is required, resulting in a rapid production process. At low absorbed dose rates, the utilization of a stabilization agent is advisable. By modifying the experimental conditions, the ratio between the chemical and radiolytic reduction process can be adjusted, thus it is possible to obtain nanoparticles with tailored characteristics, depending on the desired application.

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Nd-Fe-B MAGNETS UNDER ELECTRON IRRADIATION WITH THE ENERGY OF 23 MeV

10.46813/2020-127-023 ◽

2020 ◽

pp. 23-27

Author(s):

V.A. Bovda ◽

А.М. Bovda ◽

I.S. Guk ◽

A.N. Dovbnya ◽

V.N. Lyashchenko ◽

...

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Magnetic Flux ◽

Electron Irradiation ◽

Reference Sample ◽

Absorbed Dose ◽

Initial State ◽

Magnetic Performance ◽

And Control ◽

The Magnetic Field

Four Nd-Fe-B magnets underwent irradiation under 23 MeV electron beam. Nd-Fe-B magnets were magnetized to the technical saturation in the magnetic field of 3.5 T before electron treatment. Two Nd-Fe-B samples (1 and 2) were exposed to the direct electron beam with the energy of 23 MeV. Sample 2 was shielded by tungsten converter. The thickness of the tungsten converter was 4.72 mm. The absorbed dose for the samples was 16 GRad. Sample 3 was subjected to bremsstrahlung of electron irradiation with the energy of 23 MeV. Sample 4 was used as a reference sample for calibration and control measurements. While magnetic flux of sample under direct electron beam of 23 MeV was changed significantly, sample 2 showed the change of magnetic flux to a less degree. Magnetic performance of sample 3 corresponded closely to the initial state.

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Time-Dependent Variations in Structure of Sheep Wool Irradiated by Electron Beam

Advances in Materials Science and Engineering ◽

10.1155/2017/3849648 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Zuzana Hanzlíková ◽

Michael Kenneth Lawson ◽

Peter Hybler ◽

Marko Fülöp ◽

Mária Porubská

Keyword(s):

Electron Beam ◽

Secondary Structure ◽

Tap Water ◽

Absorbed Dose ◽

Cysteic Acid ◽

Conformational Composition ◽

Large Variability ◽

Dose Time ◽

Time Variations ◽

Usual Laboratory

Wool scoured in tap water with no special degreasing and containing a balanced humidity responding to usual laboratory conditions was irradiated by accelerated electron beam in the range of 0–350 kGy dose. Time variations of the wool structure were measured using FTIR, Raman, and EPR spectroscopy. The aim was to determine whether preexposure treatment of the wool, as well as postexposure time, affects the properties of the irradiated wool. Reactive products such as S-sulfonate, cystine monoxide, cystine dioxide, cysteic acid, disulphides, and carboxylates displayed a considerable fluctuation in quantity depending on both the absorbed dose and time. Mutual transformations of S-oxidized products into cysteic acid appeared to be faster than those in dry and degreased wool assuming that the present humidity inside the fibres is decisive as an oxygen source. EPR results indicated a longer lifetime for free radicals induced by lower doses compared with the radicals generated by higher ones. The pattern of the conformational composition of the secondary structure (α-helix, β-sheet, random, and residual conformations) also showed a large variability depending on absorbed dose as well as postexposure time. The most stable secondary structure was observed in nonirradiated wool but even this showed a small but observable change after a longer time, too.

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SU-F-T-70: A High Dose Rate Total Skin Electron Irradiation Technique with A Specific Inter-Film Variation Correction Method for Very Large Electron Beam Fields

Medical Physics ◽

10.1118/1.4956206 ◽

2016 ◽

Vol 43 (6Part13) ◽

pp. 3477-3477

Author(s):

X Yang ◽

J Rosenfield ◽

X Dong ◽

E Elder ◽

A Dhabaan

Keyword(s):

Electron Beam ◽

Dose Rate ◽

Electron Irradiation ◽

Correction Method ◽

High Dose Rate ◽

High Dose

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SM-CO BASED MAGNETIC SYSTEM FOR 10 MEV TECHNOLOGICAL ELECTRON ACCELERATOR LU-10M

East European Journal of Physics ◽

10.26565/2312-4334-2018-3-08 ◽

2018 ◽

Keyword(s):

Electron Beam ◽

Rare Earth ◽

Magnetic Flux ◽

Electron Irradiation ◽

Permanent Magnets ◽

Magnetic System ◽

Normal Component ◽

Absorbed Dose ◽

High Energy ◽

Powder Metallurgy Method

Rare-earth permanent magnets are widely used in the accelerators of charged particles. However, the magnetic performance under irradiation remains a key issue for the most high energy applications such as accelerators with the energy up to 10 MeV. The aim of the work was to assess radiation and magnetic stability of Sm-Co and Nd-Fe-B permanent magnets under the direct electron irradiation with the energy of 10 MeV and bremsstrahlung. Sm-Co and Nd-Fe-B permanent magnets were produced by powder metallurgy method including PLP for the latter. The absorbed dose imposed by electron beam was 16 Grad (the total flux of electron per 1 cm2 was 1.4х1017) and 160 Grad. The radiation activity of both Nd-Fe-B and Sm-Co magnets was within the acceptable limits after the irradiation. This makes rare-earth magnetic materials suitable for such applications. In order to avoid overheating during electron irradiation, magnets were cooled with the water (T=38 °С). In order to estimate the changes in magnetic flux, the integral of the 3D interpolation normal component of magnetic flux was used. Calculated S parameter measured in arbitrary units was chosen as integrated z-component of magnetic flux. It was shown that magnetic flux of Nd-Fe-B magnets became 0.92 and 0.717 of initial values for 16 Grad and 160 Grad correspondingly, but the magnetic flux of Sm-Co magnets had no change to the same absorbed doses. Thus, Sm-Co magnets were chosen for simulating and designing magnetic system for electron beam analysis of a technological accelerator with energy up to 10 MeV. The distance between the poles of the magnet was 25.25 mm. The highest magnetic field inside the magnetic system was 0.3110 T. The effective distance was 33.53 mm. The measured parameters of the magnetic system based on Sm-Co magnets agreed with the simulation experiment. Magnetic system can also be used to adjust the accelerator in the energy range up to 10 MeV.

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