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1
Content available Study on radiation-induced radicals giving rise to stable EPR signal suitable for the detection of irradiation in L-sorbose-containing fruits
Guzik G. P., Stachowicz W.
Nukleonika
|
2016
|
Vol. 61, No. 4
461--465
EN
The stable and complex EPR signals produced by the action of ionizing radiation on crystalline L-sorbose (C6H12O6) separated from rowan berries (Sorbus aucuparia) were studied. Isothermal heating of the samples at the temperature close to the melting point of L-sorbose (140°C) results in the modification and simplification of the EPR signal involved. In the EPR signal of heated L-sorbose, the isotropic quartet was distinguished. In the differential spectrum obtained by subtraction of normalized spectra of unheated and heated L-sorbose, the isotropic doublet was identified in addition. The DFT fitting offers the probable assignment of the EPR signals to specifi c radical structures.
2
Content available Początki i rozwój badań radiacyjnych w IBJ na Żeraniu
Stachowicz W.
Postępy Techniki Jądrowej
|
2015
|
z. 3
29--33
PL
W artykule opisano początki chemii radiacyjnej w IBJ, w tym pierwsze źródła promieniowania, pierwsze badania napromieniowanych związków nieorganicznych i organicznych. Omówiono instalację komercyjnego źródła promieniowania i liniowego akceleratora elektronów oraz rozszerzony w związku z tym program badań. Prace poznawcze obejmowały badanie roztworów soli nieorganicznych i węglowodorów alifatycznych, a oparte były na technice radiolizy impulsowej i wykorzystaniu niskich temperatur (ciekły azot, ciekły hel). Zostały rozwinięte oparte na technice EPR badania sterylizowanych radiacyjnie przeszczepów kostnych. Wdrożono sterylizację radiacyjną sprzętu medycznego oraz prowadzono badanie napromieniowanych polimerów, w tym szczepienie folii monomerami, sieciowanie i degradację. Efektem tych prac było wdrożenie i uruchomienie produkcji rur i taśm termokurczliwych.
EN
First step in radiation chemistry including construction of home-made Co-60 irradiation sources and the preliminary experiments on inorganic and organic systems are described. Installation of commercial Co-60 irradiator and linear electron accelerator followed by extended research program is discussed. Basic studies were focused on liquid solutions of inorganic salts and aliphatic hydrocarbon based on pulse radiolysis and low temperature irradiations (liquid nitrogen and helium). The EPR study on radiation sterilization of bone grafts was developed. Radiation sterilization of medical devices was implanted while polymer study i.e. radiation induced grafting of foils with monomers, cross-linking and degradation of irradiated polymers were extensively studied resulting in the implementation and further production of shrinkable tubes and tapes.
3
Content available Identification of irradiated dried fruits using EPR spectroscopy
Guzik G. P., Stachowicz W., Michalik J.
Nukleonika
|
2015
|
Vol. 60, No. 3, part 2
627--631
EN
The dominating carbohydrates in fruits are monosaccharides like fructose, glucose, sorbose and mannose. In dehydrated fruits, concentration of monosaccharides is higher than in fresh fruits resulting in the formation of sugar crystallites. In most of dried fruits, crystalline fructose, and glucose dominate and appear in proportion near to 1:1. Irradiation of dried fruits stimulates radiation chemical processes resulting in the formation of new chemical products and free radicals giving rise to multicomponent EPR signal which can be detected for a long period of time. For that reason, it is used as a marker for the detection of radiation treatment of dried fruits. It has been found that EPR spectra recorded in dried banana, pineapple, papaya, and fig samples resemble the EPR spectrum obtained by computer addition of fructose and glucose spectra taken in proportion 1:1. The decay of radiation induced EPR signals proceeds in dried fruits fast during the first month of observation and becomes much slower and almost negligible after prolonged storage. However, it remains intense enough for EPR detection even one year after processing. The radiation induced EPR signal is easily detected in dried fruits exposed to 0.5 kGy of gamma rays. Thus, the EPR method of the detection of irradiated fruits can be used for the control of dried fruits undergoing quarantine treatment with 200–300 Gy of ionizing radiation.
4
Content available Identyfikacja napromieniowania produktów spożywczych w IChTJ
Stachowicz W.
Postępy Techniki Jądrowej
|
2013
|
z. 2
20-21
5
Content available Study on organic radicals giving rise to multicomponent EMR spectra in dried fruits expose to ionizing radiation II. D-Glucose
Guzik G. P., Stachowicz W.
Nukleonika
|
2013
|
Vol. 58, No. 3
425--428
EN
Crystalline D-glucose extracted from dried resins was irradiated with 60Co gamma rays. The multicomponent EMR spectra of the samples kept at ambient temperature were compared with those heated at 105°C – the temperature close to the melting point of glucose. Normalized EMR spectra recorded with both samples were subtracted, resulting in a differential EMR spectrum. Spectral analysis of all three spectra has been done resulting in the identification of isotropic doublet of doublets assigned to less stable radical derived from parent glucose molecule.
6
Content available EPR study on sugar radicals utilized for detection of radiation treatment of food
Guzik G. P., Stachowicz W., Michalik J.
Nukleonika
|
2012
|
Vol. 57, No. 4
545-549
EN
Radicals produced by ionizing radiation in sugars, the components of dried and raw fruits give rise to stable multicomponent electron paramagnetic resonance (EPR) signals unidentified so far. The subject of the present EPR study is to identify the radicals stabilized in gamma-irradiated crystalline sugars, D(+)mannose and L(-)sorbose extracted from cranberries (Vaccininum oxycoccos) and rowan berries (Sorbus aucuparia), respectively. EPR measurements and density functional theory (DFT) simulations were employed for that purpose.
7
Two-Channel EPR Spectrometer for quantitative measurements in relation to reference sample
Duchiewicz J., Dobrucki A., Francik A., Duchiewicz T., Stachowicz W., Oleś T.
Elektronika : konstrukcje, technologie, zastosowania
|
2011
|
Vol. 52, nr 12
106-110
EN
The concept and construction of the two-channel EPR spectrometer, enabling quantitative measurements of the spins number with regard to the model sample has been described. A such spectrometer consists apart of standard blocks (microwave unit, receiver of EPR signal and magnetic field stabilizer) and of the double measuring resonator, the additional EPR signal receiver and the control program enabling simultaneous recording of the EPR signal of the sample under test and of the reference sample. A rebuilding of the designed L-Band EPR spectrometer to be suitable for quantitative dosimetry of the irradiated food has been considered.
PL
Przedstawiono budowę dwukanałowego spektrometru EPR, umożliwiającego pomiary liczby spinów względem wzorca. W skład takiego spektrometru, oprócz typowych bloków (blok mikrofalowy, odbiornik sygnału EPR oraz stabilizator pola magnetycznego) wchodzą: podwójny rezonator pomiarowy, dodatkowy układ odbiorczy sygnału EPR oraz program sterujący, zapewniający jednoczesną rejestrację sygnału pochodzącego od próbki badanej oraz od próbki odniesienia. Rozważono również możliwość przekonstruowania opracowanego spektrometru EPR na pasmo L na spektrometr nadający się szczególnie do badań dozymetrycznych napromieniowanej żywności.
8
The 2-channel EPR spectrometer Radiopan SE/X- 254x for relative quantitative measurements
Duchiewicz J., Dobrucki A., Francik A., Sadowski A., Duchiewicz T., Stachowicz W., Kupriyanova G.
Elektronika : konstrukcje, technologie, zastosowania
|
2011
|
Vol. 52, nr 11
101-103
EN
The construction of the 2-channel Radiopan EPR spectrometer, enabling quantitative measurements in relation to reference has been described. A such spectrometer consists of standard blocks (microwave unit, analog receivers of EPR signal 100kHz and 80Hz and analog magnetic field stabilizer) and of the double measuring rectangular cavity, digital magnetic field sweeper and of the special computer program, enabling simultaneous recording of the both EPR signals: of the sample under test and of the reference sample. The double rectangular cavity has been built by folding with oneself of two identical rectangular cavities. The designed spectrometer is mainly dedicated for dosimetric EPR measurements.
PL
Przedstawiono budowę dwukanałowego spektrometru EPR Radiopan, umożliwiającego pomiary ilościowe względem wzorca w paśmie X. W skład spektrometru, oprócz typowych bloków (blok mikrofalowy, analogowe odbiorniki sygnału EPR 100kHz i 80Hz oraz analogowy stabilizator pola magnetycznego) wchodzą: podwójny rezonator pomiarowy, cyfrowy układ przemiatania pola magnetycznego oraz specjalny program sterujący, zapewniający jednoczesną rejestrację obu sygnałów EPR, pochodzących od próbki badanej oraz od próbki odniesienia. Podwójny rezonator prostokątny utworzono poprzez złożenie dwóch, identycznych rezonatorów prostokątnych. Opracowany spektrometr szczególnie nadaje się do pomiarów dozymetrycznych.
9
Spektrometr Elektronowego Rezonansu Paramagnetycznego (EPR), umożliwiający ilościowe pomiary liczby spinów w badanej próbce
Duchiewicz J., Dobrucki A., Francik A., Stachowicz W., Oleś T., Duchiewicz T.
Elektronika : konstrukcje, technologie, zastosowania
|
2010
|
Vol. 51, nr 11
117-122
PL
Przedstawiono budowę dwukanałowego spektrometru EPR, umożliwiającego pomiary liczby spinów względem wzorca. W skład takiego spektrometru, oprócz typowych bloków (blok mikrofalowy, odbiornik sygnału EPR oraz stabilizator pola magnetycznego) wchodzą: podwójny rezonator pomiarowy, dodatkowy układ odbiorczy sygnału EPR oraz program sterujący, zapewniający jednoczesną rejestrację sygnału pochodzącego od próbki badanej oraz od próbki odniesienia. Rozważono również możliwość przekonstruowania opracowanego spektrometru EPR na pasmo L na spektrometr nadający się szczególnie do badań dozymetrycznych napromieniowanej żywności.
EN
The construction of the two-channel EPR spectrometer, enabling quantitative measurements of the spins number with regard to the model sample has been described. A such spectrometer consists apart of standard blocks (microwave unit, receiver of EPR signal and magnetic field stabilizer) and of the double measuring resonator, the additional EPR signal receiver and the control program enabling simultaneous recording of the EPR signal of the sample under test and of the reference sample. A rebuilding of the designed l-Band EPR spectrometer to be suitable for quantitative dosimetry of the irradiated food has been considered.
10
Content available Detection of radiation treatment of dry plant extracts by thermoluminescence and pulsed photostimulated luminescence. Comparative study
Lehner K., Malec-Czechowska K., Stachowicz W., Guzik G.
Nukleonika
|
2009
|
Vol. 54, No. 2
99-105
EN
Results of the examination of the variety of dry plant extracts (Thyme extract, Celery seed extract, Artichoke extract, Citrus aurantium extract and others) by two different detection methods are described. Both PSL and TL methods are presented and discussed. Comparative study based on the analysis of the results obtained by thermoluminescence (TL) and photostimulated luminescence (PSL) measurements delivered the arguments that preselection of detection methods based on model studies is rational to be adapted in analytical laboratories specialized in the detection of irradiated foods.
11
Content available Study on stable radicals produced by ionizing radiation in dried fruits and related sugars by electron paramagnetic resonance spectrometry and photostimulated luminescence method – I. D-fructose
Guzik G. P., Stachowicz W., Michalik J.
Nukleonika
|
2008
|
Vol. 53, suppl. 2
89--94
EN
Stability of sugar born radicals separated from irradiated Iranian dried raisins and from D-fructose by Sigma Aldrich has been studied at room temperature by EPR and PPSL methods in a period of 360 days. It has been proven for the first time experimentally that the complex EPR spectrum of irradiated sugars is changed in time and after heating. Hence, this made it possible to distinguish spectral lines of two specific radicals contributing to the formation of multicomponent spectra, recorded in both time dependent and heating experiments. The radicals measured by EPR and energy traps detected by PPSL decay at room temperature in a similar way, suggesting a similar distribution of both species in sugar crystallites. We think that our experimental approach might be useful to study interrelation between the formation and trapping of radicals and energy accumulated in crystalline matrices. In order to achieve the isolation of individual sugars from fruits the extraction and specific separation procedures have been adapted with the use of methanol, ethanol and water solvents. Our results clearly show that radicals induced by radiation in fruits (with fructose born radicals as major constituent) are stable enough at room temperature for easy identification of irradiated raisins using the EPR method.
12
Content available Reliability of light-stimulated photoluminescence (PSL) in detection of irradiated food comparison with thermoluminescence method (TL)
Guzik G. P., Stachowicz W.
Nukleonika
|
2008
|
Vol. 53, suppl. 1
25-29
EN
The detection of irradiation of several classes of food products with the use of thermoluminescence (TL) and photostimulated luminescence (PPSL) has been proceeded. The comparison of the results obtained by both methods has been done and reliability of the PPSL method as compared with the TL method evaluated. Conclusion concerning the usefulness of such evaluation to the practice has been drawn.
13
Content available remote Sterylizacja przeszczepów chirurgicznych promieniowaniem jonizującym
Stachowicz W., Kamiński A., Michalik J.
Postępy Techniki Jądrowej
|
2007
|
z. 2
9-13
14
Content available EPR study on biominerals as materials for retrospective dosimetry
Sadło J., Michalik J., Stachowicz W., Strzelczak G., Dziedzic-Gocławska A., Ostrowski K.
Nukleonika
|
2006
|
Vol. 51,suppl.1
95-100
EN
Stable paramagnetic species, induced by irradiation in biominerals, can be successfully used as an EPR dosimeter in numerous domains of scientific activity. In hydroxyapatite, the main mineral component of bones, the most stable signal is assigned to CO2 - ion radical. The signal is dose dependent and allows to determine the absorbed dose in a wide range till 20 kGy, with detection limit for tooth enamel below 1 Gy. The additive dose method was applied to EPR dating of archeological objects and EPR dosimetry after accidental overexposing during radiotherapy. It was found that the age of remains excavated from the “tomb of giants” belonging to Nuraghic culture developed in Sardinia island is about 3160 years old (1160 years BC). The dose obtained by patients during the accident at the Białystok Oncological Center was evaluated at about 75 Gy. Searching for potential dosimeters among other biominerals shows that mollusc shells have very promising properties. The lowest dose detection limit was found for an Arcidae shell. Both fresh water and sea mollusc shells are useful to be used for dosimetry in the low dose range.
15
Content available remote Identyfikacja napromieniowanej żywności
Stachowicz W.
Postępy Techniki Jądrowej
|
2005
|
z. 4
25-32
16
Content available remote Zwalczanie promieniami gamma owadów niszczących zabytkowe tkaniny, materiały wełnopochodne, futra i muzealne zbiory zoologiczne
Krajewski A., Stachowicz W.
Postępy Techniki Jądrowej
|
2003
|
Vol. 46, z. 4
36--44
17
Content available remote Zwalczanie promieniami gamma owadów niszczących drewno zabytków
Krajewski A., Stachowicz W.
Postępy Techniki Jądrowej
|
2003
|
Vol. 46, z. 2
26--35
18
Content available remote Czy wszystkie metody sterylizacji spełniają wymagania współczesnej medycyny
Stachowicz W.
Postępy Techniki Jądrowej
|
2003
|
Vol. 46, z. 4
27-35
19
Content available Detection of irradiated components in flavour blends composed of non-irradiated spices, herbs and vegetable seasonings by thermoluminescence method
Malec-Czechowska K., Stachowicz W.
Nukleonika
|
2003
|
Vol. 48, nr 3
127-132
EN
The results of experiments on the detection of irradiated component in commercial flavour blends composed of a mixture of non-irradiated spices, herbs and seasonings are presented. A method based on the thermoluminescence measurements on silicate minerals isolated from blends has been adapted. It has been proved that by applying this technique it is possible to detect 0.05% by weight of paprika, irradiated earlier with a dose of 7 kGy, which was a minor component of nonirradiated flavour blends.
20
Laboratorium Identyfikacji Napromieniowania Żywności : Instytut Chemii i Techniki Jądrowej
Stachowicz W., Malec-Czechowska K.
Analityka : nauka i praktyka
|
2000
|
nr 4
25--29
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