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1
Content available Effect of electron beam irradiation on filtering facepiece respirators integrity and filtering efficiency
Chmielewska Dagmara, Werner Łukasz, Gryczka Urszula, Migdał Wojciech
Nukleonika
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2022
|
Vol. 67, No. 2
23--33
EN
The outbreak of the COVID-19 pandemic has shown that the demand for medical masks and respirators exceeds the current global stockpile of these items, and there is a dire need to increase the production capacity. Considering that ionizing radiation has been used for sterilization of medical products for many years and electron beam (EB) irradiation enables the treatment of huge quantities of disposable medical products in a short time this method should be tested for the mask’s decontamination. In this work, three different filtering facepiece respirators (FFRs) were irradiated with electron beams of 12 kGy and 25 kGy. The results confirmed that the decrease in filtration efficiency after irradiation of all respirators results from the elimination of the electric charge from the polypropylene (PP) fibers in the irradiation process. Moreover, the applied doses may affect the thermal stability of PP fabrics, while filtering materials structure and integrity have not changed after irradiation.
2
Content available remote Structural, optical, morphological and SHG studies on 8 MeV electron beam irradiated Sr(HCOO)2·2H2O crystal
Muthupoongodi S., Manickam S. Theodore David, Mahadevan C. K., Greena J. Angel Mary, Balakumar S., Ananthapadmanabhan P. V., Shajan X. Sahaya
Materials Science Poland
|
2020
|
Vol. 38, No. 2
236--247
EN
Strontium formate dihydrate single crystals have been grown by the slow solvent evaporation method and subjected to 8 MeV electron beam (EB) irradiation at different doses, viz. 1 kGy, 10 kGy, 50 kGy and 100 kGy. The irradiated crystals have been studied by various techniques such as FT-IR, Raman, and UV-Vis-NIR spectral analyses, powder, and high resolution X-ray diffraction, thermogravimetric analysis (TG/DTA) and second harmonic generation (SHG) measurements. The morphological features of the non-irradiated and irradiated crystals were analyzed by SEM and optical microscopy studies. It has been noticed that the SHG efficiency increases while the crystalline perfection and thermal stability of the irradiated crystals decrease with the increase of EB irradiation dose. The results indicate a significant overall tuning of physical properties of strontium formate dihydrate crystals due to irradiation.
3
Content available Electron beam irradiation of r-SANEX and i-SANEX solvent extraction systems : analysis of gaseous products
Szreder T., Kocia R.
Nukleonika
|
2015
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Vol. 60, No. 4, part 2
899--905
EN
1-Octanol/kerosene mixtures and water contacted with organic solvents were used as model solutions for r-SANEX and i-SANEX extractions systems. Investigations aimed on a quantitative evaluation of gaseous products generated in these systems under exposure to an electron beam irradiation. Influence of O2, HNO3 and the presence of model ligands and complexes on the radiation chemical yields was studied. Relatively high G(H2) values (up to 420 nmol∙J-1) for the organic phase compromise the safety issues of the extraction process and should be considered on the stage of extraction apparatus design. Based on the obtained results gaseous hydrocarbons seem to have negligible impact on safety issue. The upper limit of G(H2) values in water contacted with organic phase was established to be 85 nmol∙J-1. This value is relatively low, however, the literature data indicate that G(H2) values measured in aqueous solutions are over twice higher for α-particles irradiation than for electron beam or γ-irradiation. Thus, further investigations of these systems are necessary.
4
Content available E-beam irradiation for the control of Phytophthora nicotianae var. nicotianae in stonewool cubes
Ptaszek M., Orlikowski L. B., Migdał W., Gryczka U.
Nukleonika
|
2015
|
Vol. 60, No. 3, part 2
679--682
EN
Effectiveness of electron beam irradiation was evaluated against Phytophthora nicotianae var. nicotianae, the causal agent of stem base and root rot of tomato. In laboratory trials, irradiation of 7-day-old Phytophthora cultures growing on potato-dextrose-agar (PDA) medium with 1 kGy resulted in the disintegration of the pathogen’s hyphae. Increasing the irradiation dose to 3 kGy caused decay of the hyphae. Irradiation of infested stonewool with 5 kGy caused decrease of the pathogen population about 5 times. Application of 20 kGy completely eliminated the pathogen from stonewool. Irradiation of substratum resulted in significant increase of tomato seedlings healthiness, especially when the dose 20 kGy was applied.
5
Content available Modifying effect of electron beam irradiation on magnetic property of iron-bearing minerals
Wang H., Lu S.
Physicochemical Problems of Mineral Processing
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2014
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Vol. 50, iss. 1
79--86
EN
The effect of electron beam irradiation on magnetic property of iron bearing minerals was investigated by susceptibility measurements. The results show that the magnetic susceptibility of iron bearing sulfide minerals can be enhanced remarkably by strong beam current irradiation, while the magnetic susceptibility of oxidized iron minerals keeps unchanged and even is slightly reduced. The magnetic susceptibility of arsenopyrite can reach the ferromagnetic level. The particle size of irradiated minerals makes notable effects on magnetic susceptibility. The magnetic susceptibility of irradiated minerals is enhanced greatly with reduction of particle size, and the irradiation dose corresponding to the maximum magnetic susceptibility is decreased simultaneously. Exposure of pyrite to small beam current electron irradiation can only enhance its magnetic susceptibility from 4 to 5-fold. Enhancement of magnetic property by radiation induced defects and excitation in minerals is limited. Strong beam current electron irradiation provides a novel approach to enlarge the magnetic property differences between iron bearing minerals.
6
Content available Wpływ napromieniowania wiązką elektronów na charakterystyki tribologiczne PTFE, POM i PA w skojarzeniu z anodową powłoką twardą
Duda P., Bara M., Kaptacz S.
Tribologia
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2012
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nr 3
53-60
PL
W artykule przedstawiono wyniki badań tribologicznych, stereometrycznych oraz morfologii powierzchni policzterofluoroetylenu (PTFE, Teflon), polioksymetylenu (POM, Delrin) i poliamidu (PA, Nylon) poddanych modyfikacji za pomocą wiązki wysokoenergetycznych elektronów we współpracy z powłoką tlenku aluminium (APT). Celem badań było określenie przydatności wybranych modyfikowanych tworzyw sztucznych do współpracy z wyż. wym. powłokami w niesmarowanych węzłach tarcia. Artykuł stanowi kontynuację zagadnienia dotyczącego współpracy APT z wybranymi tworzywami sztucznymi, stopami żelaza oraz materiałami ceramicznymi. Wyniki badań wykazały, że wybrane materiały zachowują się w różny sposób podczas współpracy tribologicznej z powłoką tlenkową. Zastosowanie zaproponowanej modyfikacji przede wszystkim pogorszyło właściwości tribologiczne wspomnianych tworzyw - głównie intensywność zużywania.
EN
In this paper, the authors present the results of tribological and stereometric tests as well as the results of surface morphology of polytetrafluoroethylene, polyoxymethylene, and polyamide subjected to modification with a beam of high energy electrons in collaboration with an aluminium anodic-oxide coating (AOC). The aim of this study was to determine the suitability of the selected modified polymer to work with an anodic oxide coating in non-lubricated friction nodes. The paper is a continuation of an issue related to AOC cooperation with selected polymer, iron alloys, and ceramic materials. The results showed that the selected materials behave differently during tribological cooperation with an oxide coating. A modification with the use of an electron beam deteriorated the tribological properties of these materials, mainly their wear intensity.
7
Content available Effectiveness of electron beam irradiation in the control of Rhizoctonia solani
Orlikowski L. B., Gryczka U., Ptaszek M., Migdał W.
Nukleonika
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2012
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Vol. 57, No. 4
551-554
EN
Effectiveness of electron beam irradiation was evaluated against Rhizoctonia solani, which is one of the most dangerous soil-borne pathogen, causing stem base and root rot of many horticultural plants. Treatment of in vitro cultures with 0.5 kGy significantly inhibited the pathogen's growth and the spread of necrosis on chrysanthemum leaf blades inoculated with the irradiated cultures. Application of e-beam irradiation for peat disinfection resulted in a two-fold decrease rot development in chrysanthemum stem at a dose of 5 kGy and complete inhibition at 10 kGy. For the elimination of R. solani from composted pine bark and its mixture with peat, irradiation of both substrates with 15 kGy was necessary.
8
Content available remote Effect of electron beam irradiation and plastic deformation on molar mass of medical grade ultra-high molecular weight polyethylene
Sudol M., Czaja K.
Polimery
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2010
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T. 55, nr 11-12
890-894
EN
Separated and combined electron beam irradiation (as a sterilization procedure) and plastic deformation effects on the average molar mass of ultra-high molecular weight polyethylene (UHMW-PE) were studied. It was found, that both irradiation and deformation have a different impact on the polymer structure. With the growing irradiation dose the mass-average molar mass (Mω) of the polymer soluble fraction reduces and the amount of insoluble fraction (gel) increases. On the other hand, the plastic deformation of UHMW-PE alone may be considered as not involving any destruction of polymer macromolecules. The combined effect of these factors leads to different results in comparison to their separate action and depends on the sequence of the destructive impacts on the polymer. However independently of the sequence of both external factors their synergetic effect is observed for the degradation of UHMW-PE.
PL
Badano wpływ sterylizacji metodą napromieniania strumieniem elektronów oraz deformacji plastycznej (zgniatania, rys. 1) polietylenu ultrawielkocząsteczkowego (UHMW-PE), stosowanego do wytwarzania panewek endoprotez stawu biodrowego, na masę molową polimeru. Stwierdzono, że sterylizacja wpływa na utleniającą destrukcję makrocząsteczek polimeru, której stopień zależy od użytej dawki promieniowania (zmniejszenie masy molowej masowo średniej). Procesowi temu towarzyszy sieciowanie makrocząsteczek (wzrost udziału frakcji nierozpuszczalnej). Z kolei sama deformacja plastyczna wydaje się nie mieć wyraźnego wpływu na proces degradacji. Tymczasem łączne zastosowanie obydwu czynników zewnętrznych prowadzi do odmiennych efektów, dodatkowo zależnych od kolejności ich oddziaływania. W każdym wariancie oddziaływań zewnętrznych, w którym stosowana była sterylizacja radiacyjna strumieniem elektronów (niezależnie od kolejności stosowanych oddziaływań jak też w przypadku braku deformacji), następowała wyraźna destrukcja polimeru, prowadząca do zmniejszenia jego masy molowej z poziomu ok. 1000 kg/mol odpowiadającego próbce bazowej do wartości nie przekraczającej 200 kg/mol. Towarzyszące temu zmniejszenie polidyspersyjności z wartości ok. 10 do wartości 2-4 świadczy, że degradacji ulegały przede wszystkim nieusieciowane (rozpuszczalne) frakcje polimerowe o najdłuższych łańcuchach. Wyniki badań prowadzą także do wniosku, że odkształcenia plastyczne UHMW-PE zastosowane po jego sterylizacji radiacyjnej przyczyniają się w mniejszym stopniu do degradacji i sieciowania makrołańcuchów polimeru, niż w przypadku odwrotnej kolejności działania tych czynników. Jednak w obydwu przypadkach obserwuje się synergizm współdziałania obu czynników zewnętrznych na procesy destrukcyjne makrołańcuchów polietylenowych.
9
Content available Application of electron beam irradiation for inhibition of Fusarium oxysporum f. sp. dianthi activity
Gryczka U., Ptaszek M., Migdał W.
Nukleonika
|
2010
|
Vol. 55, No. 3
359-362
EN
Electron beam irradiation was tested against Fusarium oxysporum f. sp. dianthi (Fod) a pathogen causing Fusarium wilt of carnation. Efficiency of the different radiation doses on in vitro survival and development of Fod culture on potato-dextrose agar (PDA) medium was tested. A dose of 6 kGy completely inhibited the pathogen growth. Application of radiation for microbiological decontamination of four substrates used for carnation production demonstrated that, depending on the type of substrate, doses of 10 or 25 kGy were effective in Fod elimination. All carnation plants cultivated on radiation decontaminated substrates were healthy.
10
Content available A review on electron beam flue gas treatment (EBFGT) as a multicomponent air pollution control technology
Basfar A. A., Fageeha O. I., Kunnummal N., Chmielewski A. G., Licki J., Pawelec A., Zimek Z., Warych J.
Nukleonika
|
2010
|
Vol. 55, No. 3
271-277
11
Content available remote Preparation and photocatalytic activity of Cu2O nanoparticles
Lin X. F., Zhou R. M., Zhang J. Q., Sheng X. H.
Materials Science Poland
|
2010
|
Vol. 28, No. 2
504--511
EN
An electron beam irradiation route has been developed for the preparation of Cu2O nanoparticles, with poly(ethylene glycol) (PEG, Mw = 10 000) as a template, and without using a further reducing reagent. Under various synthetic conditions, the composition of Cu2O was changed by adjusting the PEG concentration and pH values of the starting solutions. Transmission electron microscopy data revealed that the morphology evolves from an irregular shape into a sphere and cube with increasing the concentration of PEG, and cube to irregular shape with increasing pH of starting solutions. UV-vis diffuse reflectance spectroscopy data indicated that the Cu2O particles absorbed visible light. The photocatalytic activity of Cu2O was evaluated by studying the decomposition of phenol and methyl orange in aqueous solution under irradiation with visible light.
12
Content available remote Electron beam irradiation induced changes in liquid-crystal compound 5CB
Rath M. C., Sarkar S. K., Wadhawan V. K., Verma R., Das I. M. L., Dąbrowski R., Tykarska M., Dhar R.
Opto-Electronics Review
|
2008
|
Vol. 16, No. 4
399-403
EN
Electron beam irradiation studies on liquid crystal material 5CB have been carried out at a temperature where the compound exists in the isotropic liquid phase. In situ time-resolved spectroscopic characterization was carried out during the irradiation. Three different transients were observed during the 2-μs electron pulse. After about 50 μs, only one transient species was found to be present, which has an absorption peak at 360 nm. Radiolysed sample exhibits a broad absorption at ∼ 400 nm. The dielectric measurements show that even a low level of irradiation results in a dramatic increase in the component of dielectric permittivity normal to the long axes of the molecules ε ⊥', and a corresponding decrease in the dielectric anisotropy (Δ ε'=ε II — ε ⊥'). These studies show that 5CB is prone to substantial radiation damage on exposure to the beam of high-energy electrons.
13
Content available remote Influence of electron radiation on surface free energy of low density polyethylene film
Żenkiewicz M.
Journal of Achievements in Materials and Manufacturing Engineering
|
2007
|
Vol. 25, nr 2
43-46
EN
Purpose: of this paper is to study the effect of the electron radiation, generated in a high voltage accelerator, on surface free energy (SFE) of low density polyethylene film. Design/methodology/approach: An LAE 13/9 linear accelerator (former USSR) was used to irradiate the examined polyethylene film. The maximum electron energy was 13 MeV, controllable energy range, 5-13 MeV, and average power of the electron beam, 9 kW. The contact angles were measured with a G 11 goniometer (Krüss GmbH, Germany) using doubly distilled water, glycerol, formamide, diiodomethane, and alpha bromonaphthalene. The calculations of SFE were done by means of the Owens Wendt or the van Oss-haudhury-Good methods. Findings: The value of the SFE for the polyethylene film, increasing monotonically with the radiation dose, depends on both the applied method of calculation and the set of measuring liquids. The differences between the results obtained with these two methods and sets of liquids generally increase with the radiation dose. Research limitations/implications: The SFE value of polyethylene film depends not only on the intermolecular interactions originating in several outer atomic layers of the film but also on the intermolecular interactions occurring in the measuring liquids and on the way of performing investigations. Thus, it may be compared only when determined with the same method and using the same measuring liquids. Practical implications: The results of presented research allow determining the recommendations referring to the optimization of irradiation technology of low density polyethylene film. Originality/value: The differences in the SFE values calculated with the Owens Wendt and the van Oss Chaudhury-Good methods depend not on only on the kind of the calculation method but also on the kind of measuring liquid used in contact angle measurement.
14
Wpływ elastomeru termoplastycznego i dawki promieniowania elektronowego na wydłużenie względne przy zerwaniu folii poliolefinowej
Czupryńska J., Karasiewicz T., Polański J., Żenkiewicz M.
Zeszyty Naukowe. Chemia i Technologia Chemiczna / Akademia Techniczno-Rolnicza w Bydgoszczy
|
2006
|
z. 11
23-26
PL
Przedstawiono wpływ dawki promieniowania elektronowego i kompatybilizatora na wydłużenie względne przy zerwa-niu folii wytłoczonej z mieszanin polimerowych, zawierających równe części wagowe PE-LD, PE-HD i PP oraz 5, 10 lub 15% SEBS funkcjonalizowanego bezwodnikiem maleinowym. Folie te napromieniono elektronami o dużej energii w zakresie dawek od 0 do 300 kGy. Wraz ze wzrostem dawki promieniowania elektronowego do 50 kGy wydłużenie względne przy zerwaniu maleje dla wszystkich badanych próbek folii, natomiast powyżej tej dawki zmiany te nie ulegają już istotnym zmianom.
EN
The influence of the electron irradiation dose and compatibilizer on elongation at the break of films made from polymer blends which contain equal weight parts of the PE-LD and PE-HD and PP and 5%, 10% or 15% SEBS-g-MA were described. The films were irradiated with electron beam of high energy in the range of doses from 0 to 300 kGy.
15
Wpływ promieniowania elektronowego na właściwości mechaniczne folii z mieszanin polimerowych
Czupryńska J., Karasiewicz T., Polański J., Żenkiewicz M.
Inżynieria i Aparatura Chemiczna
|
2006
|
Nr 3 sp.
14-15
EN
Influence of the electron irradiation dose and two compatibi-lizers on the plasticity border and the elongation at break of films made from polymer blends containing equal weight parts of the PELD, PEHD and PP, and also 1% of trimethylol propanetriacrylate (TMPTA) or 2,5% of polyethylene wax was described. Films were irradiated with a high-energy electron beam of the dose range from 0 to 300 kGy.
16
Organic pollutants treatment by using EB-irradiation
Chmielewski A. G., Sun Y., Bułka S., Zimek Z.
Polish Journal of Applied Chemistry
|
2005
|
Vol. 49, nr 1-2
177-182
EN
Volatile organic compounds, which are emitted into atmosphere, are very harmful to the environment and human health. Organic compounds treatment by using electron beam(EB) irradiation has been studied. 1,4-dichlorobenzene (1,4-DCB), benzene and polycyclic aromatic hydrocarbons(PAHs) treatment by using EB-irradiation have been investigated. It was found that EB is a promising technology for removal pollutants from industrial off-gases.
17
Content available remote Chemia radiacyjna a elastomery
Zagórski Z.P., Rajkiewicz M.
Elastomery
|
2003
|
T. 7, nr 4
9-17
PL
W artykule omówiono elementy chemii radiacyjnej wspólne wszelkim polimerom, a więc dotyczące i elastomerów, na tle chemii radiacyjnej ośrodków stałych. Omówiono dotychczasowe publikacje na temat chemii radiacyjnej wybranych elastomerów, ze szczególnym uwzględnieniem wcześniejszego dorobku w tej dziedzinie Zakładu Chemii Radiacyjnej Instytutu Badań Jądrowych w Warszawie. Zwrócono uwagę na elementy chemii i fizykochemii elastomerów w przebiegu reakcji inicjowanych promieniowaniem jonizującym. Przedstawiono prognozy, co do kierunku dalszego rozwoju obróbki radiacyjnej elastomerów wiązką elektronów dużej mocy. Przegląd dotyczy założeń grantu KBN zrealizowanego w latach 2001-2004.
EN
Elements of radiation chemistry common for elastomers and all other polymers, on the background of radiation chemistry of solid phase are presented in this article. The discussion of publications dealing with radiation chemistry of selected elastomers, with consideration of early achievments of the Department of Radiation Chemistry in the Institute of Nuclear Research. Elements of chemistry and physical chemistry of elastomers, which influence the course of reactions initiated by ionizing radiation, are discussed. Assumptions are expressed, concerning the future developments of applications of high power EB radiation processing of elastomers. The present survey is connected with the grant of Polish Committee of Scientific Research, realized in 2001-2004.
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