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1

Datowanie luminescencyjne. Konstrukcja napromieniacza do weryfikacji efektu mocy dawki

Mandowski Arakdiusz, Mandowska Ewa, Smyka Robert, Majgier Renata, Szufa Katarzyna, Maternicki Krzysztof

Przegląd Elektrotechniczny

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2021

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R. 97, nr 2

24--27

PL

Znając wartość naturalnego tła promieniowania można sposób datować materiały archeologiczne i geologiczne metodami luminescencyjnymi. Szacujemy wiek porównując dawkę naturalną z dawką laboratoryjną. Moce tych dawek różnią się o wiele rzędów wielkości. Nie wiadomo, czy takie porównanie jest uzasadnione. W artykule przedstawiono wyniki teoretyczne i doświadczalne dotyczące efektu mocy dawki oraz koncepcję kontrolowanego elektronicznie napromieniacza do testowania tego efektu.

EN

Knowing the value of the natural radiation background, it is possible to estimate the age of archaeological and geological materials using luminescence methods. We estimate the age by comparing the natural dose with the laboratory one. The dose rates for these two cases doses may fiffer by many orders of magnitude. It is not known whether such a comparison is justified. The article presents theoretical and experimental results concerning the dose rate effect as well as the concept of an electronically controlled irradiator to test this effect.

2

European inter-comparison studies as a tool for perfecting irradiated food detection methods

Guzik Grzegorz Piotr, Michalik Jacek

Nukleonika

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2021

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Vol. 66, No. 3

91--97

EN

In this paper, we present the results of inter-comparison studies on identification of irradiated food carried out by the leading European laboratories from 1991 to 2018. In 1990s, the Federal Institute for Health Protection of Consumers and Veterinary Medicine in Germany played the leading role in the organization of the inter-laboratory tests on this subject. At the beginning of the present century, the Spanish Agency for Food Safety and Nutrition and Food National Spanish Centre took over this role. In total, 47 international tests were carried out in which nearly 500 samples of alimentary products were analysed in 37 laboratories from 14 European countries. The tests were aimed at proving the reliability of analytical methods – thermoluminescence (TL), photostimulated luminescence (PSL), and electron paramagnetic resonance (EPR) spectroscopy – for identification of specific irradiated food products and to control the analytical skills and experience of participating laboratories. The results made possible a discussion on why some irradiated food samples are more difficult for identification. In general, the tests showed that TL measurements of products such as herbs, nuts, peppers, and raisins, and EPR studies of fish and chicken bones, fresh strawberries, and dried fruits could be used as reliable control methods. The challenge that control laboratories are facing now, is related to the identifi cation of complex food products such as diet supplements or biopharmaceuticals, in which only some additives are irradiated.

3

Luminescence characteristics of intraplate-derived olivines

Clark-Balzan Laine, May Venera R., Preusser Frank

Geochronometria

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2021

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Vol. 48, no.1

73--94

EN

Olivine has so far attracted limited attention as a potential luminescence dosimeter. In particular, there is a dearth of information concerning the luminescence properties of geochemically characterised, pure olivine samples. Six well-characterised olivine samples from four intraplate settings are investigated in this study, including emission wavelengths and intensities, growth of signal with absorbed dose, signal stability and recovery of a given dose with a single aliquot regeneration (SAR) protocol. All tested olivines share a low-temperature (90–100°C) UV/blue thermoluminescence (TL) peak, and five of six samples also produce a low-temperature red/yellow emission. Higher temperature TL peaks, which would be thermally stable over geological timescales and could be used for dating, are rarely observed at low doses (c. 46 Gy), but detectable though dim at significantly higher doses (c. 460 Gy). Photostimulated luminescence (PSL) emissions are very dim, but reliably detected emissions are stimulated by blue, yellow and infrared (IR) light. PSL yielded generally successful dose recovery results; however, all tested signals are prone to significant anomalous fading and complex thermal transfer between unbleachable and bleachable traps. These characteristics must be addressed if olivine is to be used as a natural dosimeter for luminescence dating. Given the variety of luminescence responses, it appears that olivine samples in future dating work may need to be individually characterised prior to measurement.

4

Remaining useful life prediction of bearings with different failure types based on multi-feature and deep convolution transfer learning

Wu Chenchen, Sun Hongchun, Lin Senmiao, Gao Sheng

Eksploatacja i Niezawodność

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2021

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Vol. 23, no. 4

685--694

EN

The accurate prediction of the remaining useful life (RUL) of rolling bearings is of immense importance in ensuring the safe and smooth operation of machinery and equipment. Although the prediction accuracy has been improved by a predictive model based on deep learning, it is still limited in engineering because lots of models use single-scale features to predict and assume that the degradation data of each bearing has a consistent distribution. In this paper, A deep convolutional migration network based on spatial pyramid pooling (SPP-CNNTL) is proposed to obtain higher prediction accuracy with self-extraction of multi-feature from the original vibrating signal. And to consider the differences of the data distribution in different failure types, transfer learning (TL) added with maximum mean difference (MMD) measurement function is used in the RUL prediction part. Finally, the data of IEEE PHM 2012 Challenge is used for verification, and the results show that the method in this paper has high prediction accuracy.

5

Czytnik OSL z nieliniową funkcją stymulacji optycznej

Mandowska E., Smyka R., Mandowski A., Kieszkowski R., Majgier R.

Elektronika : konstrukcje, technologie, zastosowania

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2018

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Vol. 59, nr 9

12--15

PL

Optycznie stymulowana luminescencja (OSL) jest jedną z podstawowych metod pomiaru dawki promieniowania jonizującego. Mierzona luminescencja jest proporcjonalna do dawki pochłoniętej przez detektor. Czytniki OSL wykorzystują do stymulacji zazwyczaj światło monochromatyczne o stałej intensywności (CW-OSL) lub zmieniające się liniowo (LM-OSL). Nowy czytnik luminescencyjny Helios X1 oferuje szersze możliwości. Stymulacja detektora może być dokonywana za pomocą dwóch długości fali, które mogą być modulowane nieliniowo niezależnie od siebie. Ten sposób stymulacji umożliwia uzyskanie dodatkowych informacji o właściwościach detektora.

EN

Optically stimulated luminescence (OSL) is one of the basic methods for the measurement of the dose of ionizing radiation. The measured luminescence is proportional to the dose absorbed by the detector. Typically, OSL readers use monochrome light with constant intensity (CW-OSL) or linearly modulated light (LM-OSL) for stimulation. The new Helios X1 luminescence reader offers greater possibilities. The detector stimulation can be performed using two wavelengths that can be independently and non-linearly modulated. This method of stimulation provides additional information relating to detector properties.

6

Investigation of the role of the production process on the luminescence of sea salt products

Hunter P. G., Spooner N. A.

Geochronometria

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2017

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Vol. 44, no. 1

121--128

EN

Luminescence dosimetry assumes samples of a given material with diverse provenances behave in a predictable manner, allowing a standardised testing protocol, such as SAR for quartz, to be employed. This article demonstrates that distinct salt products derived from a single manufacturer’s feedstock retain comparable luminescence behaviour. This is the basis of a standardised test protocol: uniting testing procedures which have been shown to be individually applicable. Generalization across samples from different manufacturers and processes is currently under investigation.Luminescent evaluation of five samples produced by Cheetham & Co. gave useful intensities for all emission bands (590 nm, 420 nm and 360 nm TL and blue stimulated OSL), with the spectral and intensity balance of emissions generally similar for each sample. 590 nm emission sensitization was noted after preheating samples to 135°C and 300°C for five minutes. But, the 360 nm TL emission from feedstock salt was a factor of five greater than the same signal from the other processed samples despite the OSL intensity being similar to the other samples.Spectrum variation between aliquots as measured by the 3D TL spectrometer was also investigated and found to be minimal for both the first and second TL glow cycles.

7

Oszacowanie metodami EPR, TL i PPSL odpowiedzi próbek przy wykrywaniu potencjalnego napromieniowania żywności

Guzik G. P.

Postępy Techniki Jądrowej

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2015

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z. 4

13--16

PL

VI międzynarodowe porównanie wiarygodności trzech najważniejszych metod analitycznych stosowanych do wykrywania napromieniowanej żywności zorganizowano w 2015 r. pod auspicjami Ministerstwa Zdrowia i Hiszpańskiej Agencji Bezpieczeństwa Żywności i Żywienia (AESAN) oraz Krajowego Centrum Żywności (CNA). W badaniu zatytułowanym „Międzynarodowe badanie porównawcze metodami Tl, PSL i EPR, 6 runda” brało udział dziewiętnaście specjalistycznych laboratoriów z kilku krajów europejskich. CNA jest doświadczonym laboratorium, posiadającym akredytację do wykrywania napromieniowanej żywności metodami thermoluminescencji (TL), fotostymulowanej luminescencji (PSL) i spektroskopii elektronowego rezonansu paramagnetycznego (EPR). Większość laboratoriów uczestniczących w porównaniu międzylaboratoryjnym posiada również taką akredytację. Asortyment produktów spożywczych dostępnych na rynku jest coraz szerszy, jednak nie wszystkie z nich są testowane pod kątem ich potencjalnego napromieniowania. Jest to istotny argument przemawiający za udziałem wszystkich laboratoriów w porównaniach międzylaboratoryjnych, takich jak obecnie przeprowadzane.

EN

Under the auspices of the Ministry of Health and the Spanish Agency for Food Safety and Nutrition (AESAN) the National Food Centre (CNA) in 2015 has organised the 6th international exercise for testing the reliability of three most important analytical methods used for the detection of irradiated food. The study named ”Intercomparative exercise for quality assurance on Tl, PSL and EPR Irradiated food detection methods, 6 th Round” assembled nineteen specialized laboratories from several European countries. The organizing institution CNA possess accreditation for the detection of irradiated food and is experienced in thermoluminescence (TL), photostimulated luminescence (PSL) and electron paramagnetic resonance spectroscopy (EPR). It is also the case with most of participating laboratories. Presently the spectrum of food products found in the market is significantly extended and many of this products were not tested or validated whether their radiation treatment is detectable. This is a strong argument for the need of the organization of intercomparative studies as the present one.

8

Influence of in Situ Temperature on the Sensitization of Quartz: a Simulation Study

Koul D. K., Patil P. G.

Geochronometria

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2015

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Vol. 42, no.1

28--40

EN

The influence of ambient geological and burial temperatures, prevailing in nature, on the charge population of the defect centers and, eventually, the sensitivity of the luminescence emission of quartz was simulated using empirical model. Various permutation and combination of these temperatures were incorporated so as to observe, both, the collective and independent impact of these two temperatures on the charge kinetics. The results of seem to demonstrate the role of the ambient temperature in the sensitization of quartz mineral.

9

Holocene sediments of the Ustka Cliff (Northern Poland) in view of radiometric dating

Wróblewski R., Fedorowicz S., Kamieńska K.

Geochronometria

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2013

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Vol. 40, no. 3

187--194

EN

The cliff in Ustka is an active one. The area is one of the most eroded sea shores of the Polish coast. The Ustka Cliff mainly consists of Holocene sandy deposits, but its basis is built of gla-cial till and clay. Field search allowed to recognize the structure and sedimentary conditions of Holo-cene deposits exposed in the cliff. A comparison of dating results obtained for fossil soils and peat as well as aeolian deposits, using 14C and TL methods, respectively, with available literature records is presented. The evaluation of results obtained allowed to define three main dune-forming phases for the first time for this part of the Polish coast. During the research studies new data on the processes and environmental conditions was gained and the development of structure of the area during the last 10 thousand years was reconstructed. The analysis of available data from other sections of the south-ern Baltic coast shows that results obtained are age similar to those determined for the Łeba Spit. The research is part of a project concerning the geomorphology of the Ustka Bay.

10

Technical Notes : Practical Concerns Associated with Single-Number Ratings in Measuring Sound Transmission Loss Properties of Partition Panels

Garg N., Kumar A., Maji S.

Archives of Acoustics

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2013

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Vol. 38, No. 1

115--124

EN

The paper presents an extensive review investigating the practical aspects related to the use of single- number ratings used in describing the sound insulation performance of partition wall panels and practical complications encountered in precise measurements in extensive frequency range from 50 Hz to 5 kHz. SWOT analysis of various single number ratings is described. A laboratory investigation on a double wall partition panel combination revealed the significant dependence of STC rating on transmission loss at 125 Hz attributed to 8 dB rule. An investigation conducted on devising alternative spectrums of aircraft noise, traffic noise, vehicular horn noise and elevated metro train noise as an extension to ISO 717-1 Ctr for ascertaining the sound insulation properties of materials exclusively towards these noise sources revealed that the single-number rating Rw + Ctr calculated using ISO 717-1 Ctr gives the minimum sound insulation, when compared with Rw + Cx calculated using the alternative spectrums of aircraft noise, traffic noise, etc., which means that material provides a higher sound insulation to the other noise sources. It is also observed that spectrum adaptation term Cx calculated using the spectrum of noise sources having high sound pressure levels in lower frequencies decreases as compared to ISO 717-1 Ctr owing to significant dependence of Ctr at lower frequencies.

11

Surface dating by luminescence: an overview

Liritzis I.

Geochronometria

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2011

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Vol. 38, no. 3

292-302

EN

Daylight radiation resets luminescence ‘clock’ to zero on rock surfaces, but transmission depends on the transparency of the rock. On burial, surfaces are no longer exposed to daylight and ac-cumulation of trapped electrons takes place till the excavation. This reduction of luminescence as a function of depth fulfils the prerequisite criterion of daylight bleaching. Thus rock artefacts and mon-uments follow similar bleaching rationale as those for sediments. In limestone and marble, daylight can reach depths of 0.5-1 mm and up to 16 mm respectively, while for other igneous rocks e.g. quartz in granites, partial bleaching occurs up to 5mm depth under several hours of daylight exposures and almost complete beaching is achieved in the first 1 mm within about 1 min daylight exposure. The ‘quartz technique’ for limestone monuments containing traces of quartz enables their dating with Op-tically Stimulated Luminescence (OSL) techniques. The surface luminescence (thermoluminescence, TL or OSL) dating has been developed and further refined on various aspects of equivalent dose de-termination, complex radiation geometry, incomplete bleaching etc. A historical review of the devel-opment including important applications, along with some methodological aspects are discussed.

12

An attempt to estimate firing temperature using OSL pre-dose sensitization of quartz

Koul D. K., Chougaonkar M. P.

Geochronometria

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2011

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Vol. 38, no. 3

217-222

EN

The estimation of firing temperature of ceramics using methods based on pre-dose sensiti-zation of the 110°C TL peak of quartz have yielded incoherent results. Recently the fast component of the CW-OSL of quartz has been observed to have pre-dose characteristics similar to that of the 110°C TL peak. The motivation for this study has been to look into the feasibility of this signal, the OSL counter part of pre-dosed TL emission, for the firing temperature identification. The variation in the sensitization ratio of the TL and OSL emissions with different heating temperatures was also utilized to unveil the firing temperature mark of the specimen.

13

Infrared Stimulated Luminescence and thermoluminescence dating of archaeological samples from Turkey

Meriç M., Atlihan M. A., Koşal M., Yüce. Ü R., Cinaroglu A.

Geochronometria

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2009

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Vol. 34

25-31

EN

In this study, the potential of Infrared Stimulated Luminescence (IRSL) and thermoluminescence (TL) for dating the archaeological samples (pottery sherds and soil sample adhered to surface of human bone) which were taken from a Necropolis was investigated. Archaeological sherds taken from Nusaybin (Mardin, Turkey), an archaeological site of archaic and Hellenistic period (from 330 BC to 30 AD), were dated. Samples were prepared by the fine grain technique and paleodose values were estimated by using multiple aliquot additive dose (MAAD) and single aliquot regenerative dose (SAR) procedures. The annual doses of uranium and thorium were determined by using the low level alpha counter. The potassium contents, which have no alpha activity, were determined by XRF equipment. The average age of the sherds were found to be 2375 ± 170 years which is in good agreement with the archaeological evidence involving architecture of castle wall, Necropolis and column sherds in the vicinity of the site.

14

TL and OSL dating of sediment and pottery from two Syrian archaeological sites

Sánchez J. S., Mosquera D. F., Fenollós J. L. M.

Geochronometria

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2008

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Vol. 31

21-29

EN

Luminescence dating is widely applied nowadays, mainly for archaeological material and artefacts and sediments of all types and origins. However, optically stimulated luminescence (OSL) from archaeological sediment, originated from mud brick buildings has been hardly studied. The archaeological sites of Tall Abu Fahd and Tall Qsubi are located in the Middle Euphrates Valley, Deir ez-Zor district, Syria. These two Bronze Age sites were recently discovered by a Spanish-Syrian team from the Directorate General of Antiquities and Museums (Damascus) and the University of Coruna. Both sites were dated (about 3.5 ka BC) by typological pottery classification. Sediment and pottery samples from these archaeological sites were collected for luminescence dating. Several analytical procedures for obtaining equivalent doses were tested on the sediment samples. Blue OSL from quartz subsamples and IRSL, post IRSL Blue OSL from feldspar contaminated quartz and polymineral subsamples were performed to obtain OSL ages. For the pottery samples, additive dose TL on a coarse grain feldspar contaminated quartz subsample was performed as well. Results have shown agreement among all the luminescence procedures tested on the Tall Abu Fahd site samples after fading correction, showing ages around 2.7 ka BP. Obtained ages from the other site samples show disagreement among quartz blue OSL and the other subsamples. Fading ratios allow correcting age underestimations from the polymineral post-IR OSL signal. However, the polymineral IRSL signal still shows underestimation. Final sediment and pottery ages have shown good agreement. Older 14C independent age (3.32 ka BP) corresponds to occupational periods of the site while sediment ages are attributed to a post occupation phase.

15

Construction of a portable mini luminescence-measurement system equipped with a miniature X-ray generator

Takeuchi T., Schibutani T., Hashimoto T.

Geochronometria

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2008

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Vol. 30

17-22

EN

For the purpose of both luminescence dosimetry and dating, a new portable mini automated luminescence-measuring system has been developed. The main parts of the new system consist of the stimulation unit, an irradiation unit and the photon detector. The size of the main measuring box is approximately 300×300×300 mm. In particular, to keep the electric power as low as possible, a miniature X-ray (Oxford, Eclipse II reflection target) generator and a metal-packaged photomultiplier tube (PMT) (Hamamatsu photonics, H7421-40) were adopted here. 16 blue LEDs were employed for the stimulation of quartz OSL. The same LED holder can be used for pulsed-OSL (P-OSL) measurements. The weight of the main part of this system was about 15 kg. In order to check the usefulness of the new system, red thermoluminescence (RTL) glow curves were measured to estimate the signal-to-noise ratio (S/N ratio) using a volcanic quartz sample. These results show that the new system improves the S/N ratio in comparison with an existing handmade system. The estimated RTL equivalent (or paleo) dose using quartz extracted from an archaeological roof tile of Shin-Yakushiji temple by means of the SAR protocol was in good agreement with previous measurements. This proves that the new system is suitable for practical use for RTL-measurements either for dosimetry or for dating with a high S/N ratio.

16

Age correlation of loess with other Pleistocene deposits on the basis of TL and OSL dating

Fedorowicz S.

Geochronometria

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2007

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Vol. 27

27-32

EN

The author collected 26 samples from six loess profiles located in Poland and Ukraine and 16 samples from three galcigenic profiles in Lithuania. TL and OSL dates were obtained for the samples. The TL dates were calculated in the Gdańsk University laboratory and the OSL dates were obtained by the Institute of Physics Laboratory at the Silesian Technical University. The dating results were referred to the OSL = f(TL) chart. In respect of luminescent dating results, the Upper Vistulian loess shows a high similarity of TL and OSL dates. It means that loess formation took place in conditions conductive to ensure that solar radiation the grains were exposed to reduce the energy accumulated in them. The TL dates of Middle and Upper Vistulian loess are slightly older than the OSL dates. The largest discrepancies were found in soil sample dates. The analysis of glacigenic profile dates is not unambiguous. The fact that the TL dates are older than the OSL dates may mean that during deposition the conditions were not sufficiently conductive to reduce the energy stored earlier in the grains examined with the TL method. This time could have been sufficient to reduce the energy examined with the OSL method.