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1
Content available remote Preparation and photocatalytic activity of Cu2O nanoparticles
100%
Lin X. F. , Zhou R. M. , Zhang J. Q. , Sheng X. H.
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tom 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.
2
Content available E-beam irradiation for the control of Phytophthora nicotianae var. nicotianae in stonewool cubes
100%
Ptaszek M. , Orlikowski L. B. , Migdał W. , Gryczka U.
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tom 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.
3
Content available LONG-TERM RADIATION-INDUCED EFFECTS ON SOLID STATE CHITOSAN
100%
Gryczka U.
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2021
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tom 26
80-88
EN
Treatment of chitosan with ionising radiation is one of the methods by which it is modified for various applications. However, in the case of chitosan irradiated in the solid state, the radicals formed during irradiation can be stabilised in its crystalline phase and subsequently cause post-irradiation changes. It has been observed that further degradation of the polymer occurs during storage of the irradiated polymer, resulting in an increase in oxidation products and a decrease in deacetylation degree. This effect results from the transformation of radicals leading to the formation of stable nitroxyl radicals, a process observed years after irradiation.
4
Content available Electron beam irradiation of r-SANEX and i-SANEX solvent extraction systems : analysis of gaseous products
100%
Szreder T. , Kocia R.
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tom 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.
5
Content available Modifying effect of electron beam irradiation on magnetic property of iron-bearing minerals
100%
Wang H. , Lu S.
Physicochemical Problems of Mineral Processing
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2014
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tom 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 Effectiveness of electron beam irradiation in the control of Rhizoctonia solani
88%
Orlikowski L. B. , Gryczka U. , Ptaszek M. , Migdał W.
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tom 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.
7
Content available Effect of electron beam irradiation on filtering facepiece respirators integrity and filtering efficiency
75%
Chmielewska D. , Werner Ł. , Gryczka U. , Migdał W.
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2022
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tom 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.
8
Content available Wpływ napromieniowania wiązką elektronów na charakterystyki tribologiczne PTFE, POM i PA w skojarzeniu z anodową powłoką twardą
63%
Duda P. , Bara M. , Kaptacz S.
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tom 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.
9
Content available remote Effect of electron beam irradiation and plastic deformation on molar mass of medical grade ultra-high molecular weight polyethylene
63%
Sudol M. , Czaja K.
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2010
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tom 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.
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