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1

Quantum Entanglement Degree, Mean Positronium Lifetime, and the 3γ/2γ Annihilation-Rate Ratio as Novel PET Biomarkers for Hypoxia - Concept, Challenges, and Predictions

Moskal Paweł

Bio-Algorithms and Med-Systems

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2026

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Vol. 22, no. 1

56--77

EN

Objective: Hypoxia is a critical factor in tumour aggressiveness, metastasis, and treatment resistance. Despite its clinical significance, a non-invasive, high-precision method for assessing and mapping tissue oxygenation in vivo remains a major challenge in medicine. This study explores the potential of positronium imaging and quantum entanglement (QE) imaging as next-generation biomarkers for hypoxia. This manuscript introduces a novel method to assess tissue oxygen concentration via the QE of photons originating from positronium - a bound state of an electron and a positron - which is produced within the patient’s body during positron emission tomography (PET). We also investigate the possibility of assessing hypoxia by simultaneously detecting positronium lifetime and the positronium decay rate ratio. Methods: We introduce two distinct quantum sensing approaches. Method 1 utilises the correlation between oxygen concentration and ortho-positronium (oPs) decay rates, relying on the simultaneous measurement of the mean oPs lifetime (τoPs) and the 3γ-to-2γ annihilation rate ratio of oPs (RoPs-3γ/2γ ). Method 2 introduces a novel hypothesis based on the degree of QE of annihilation photons. This method leverages recent discoveries indicating that the degree of QE is sensitive to the relative contribution of annihilation mechanisms (pick-off vs. conversion), which in turn depends on the oxygen concentration. We estimate the rate of conversion processes as a function of the partial pressure of oxygen (pO2) in water, isopropanol, cyclohexane, isooctane, and adipose tissue. We consider the dependence of RoPs-3γ/2γ and τoPs, as well as the degree of QE, on oxygen pressure in the studied substances. Finally, we derive a formula for pO2 as a function of RoPs-3γ/2γ and τoPs and estimate the measurement accuracy required for these parameters - and for the degree of QE - to sense in-vivo oxygen pressure in the range between hypoxic and physoxic conditions. Results: Theoretical models and quantitative estimates for RoPs-3γ/2γ , τoPs and for the degree of QE (CQE and RQE) as a function of pO2 are provided for water, organic solvents (isopropanol, cyclohexane, isooctane), and adipose tissue. Applying the formulas derived under the working hypothesis that in pick-off process the photons are not entangled, we estimated that for pO2 = 0, the degree of QE CQE is equal to 0.890 for adipose, 0.886 for isopropanol, 0.867 for water, 0.818 for cyclohexane, and 0.784 for isooctane. These results indicate that distinguishing between various tissue types requires a precision of σ(CQE) ≈ 0.01. We also estimated the values of τoPs, RoPs-3γ/2γ , and R3γ/2γ , as well as the changes in τoPs, RoPs-3γ/2γ and CQE between physoxic (pO2 ≈ 50 mmHg) and hypoxic (pO2 = 10 mmHg) conditions which amount to ΔτoPs = 5 ps (water), 48 ps (adipose), 182 ps (isopropanol), 187 ps (cyclohexane), 444 ps (isooctane), ΔRoPs-3γ/2γ = 0.000045 (water), 0.0004 (adipose), 0.0015 (isopropanol), 0.0015 (cyclohexane), 0.0036 (isooctane), and ΔCQE = 0.0003 (water), 0.0019 (adipose), 0.0054 (isopropanol), 0.0106 (cyclohexane), 0.0243 (isooctane). To distinguish between physoxic and hypoxic conditions in vivo, the measurement precision σ(τoPs), σ(RoPs-3γ/2γ ) and σ(CQE) must be several times higher than the predicted changes in these values. Conclusions: This work establishes a theoretical and methodological foundation for using the QE of photons and the properties of positronium as transformative diagnostic tools for the non-invasive assessment and mapping of tissue oxygenation in the human body. It demonstrates that QE can serve not only as a tool for improving PET image quality through noise reduction, but also as a completely new category of biomarker. Quantitative estimations of the effect of oxygen pressure on positronium parameters, as well as the event statistics required for hypoxia assessment, are feasible using the multi-photon total-body J-PET scanner based on plastic scintillators. Furthermore, such assessments will be possible with next-generation, high-sensitivity crystal-based PET scanners, provided they are upgraded to support multi-photon signal acquisition for τoPs and 3γ-to-2γ imaging, and double Compton scattering for imaging CQE - the degree of QE.

2

Production of alternative fuels and valuable chemicals from plastic waste

Kotowicz Janusz, Niesporek Kamil, Baszczeńska Oliwia, Brzęczek Mateusz

Rynek Energii

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2025

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Nr 1

64--70

EN

Plastics, due to their organic decomposition capability, pose a significant threat to the natural environment. Microand nanoparticles of plastic infiltrate the air, aquatic ecosystems, and the food chain, poisoning living organisms. One of the most commonly used plastics is polyethylene terephthalate (PET), which accounts for 6.20% of the global synthetic polymer production. In recent years, interest in chemical recycling has increased as an alternative to traditional PET waste disposal methods. Polyethylene terephthalate can be broken down through hydrolysis into ethylene glycol (EG), which can then be converted into glycolic acid (GA) through further catalytic processes. The article presents the challenges associated with managing PET waste, with a review of the latest research on the chemical recycling of this material, particularly focusing on the conversion pathway PET → EG → GA. Additionally, the concept developed within the PHOENIX project is presented, which involves transforming PET into GA while simultaneously producing propanol from CO􀬶, which can be used as fuel in diesel engines.

PL

Tworzywa sztuczne ze względu na ich organiczną zdolność do rozkładu stanowią poważne zagrożenie dla środowiska naturalnego. Mikro- i nanocząsteczki plastiku przenikają do powietrza, ekosystemów wodnych oraz łańcucha pokarmowego, zatruwając organizmy żywe. Jednym z najczęściej stosowanych tworzyw sztucznych jest politereftalan etylenu (PET), którego udział W globalnej strukturze produkcji polimerów syntetycznych wynosi 6,20%. W ostatnich latach wzrosło zainteresowanie recyklingiem chemicznym jako alternatywą dla tradycyjnych metod utylizacji odpadów PET. Politereftalan etylenu może być rozkładany poprzez proces hydrolizy do glikolu etylenowego (EG), który następnie może zostać przekształcony w kwas glikolowy (GA) w dalszych procesach katalitycznych. W artykule przedstawiono wyzwania związane z zagospodarowaniem odpadów PET, z przeglądem najnowszych badań nad chemicznym recyklingiem tego materiału, ze szczególnym uwzględnieniem konwersji na ścieżce PET —-› EG ——-> GA. Dodatkowo została przedstawiona również koncepcja realizowana w ramach projektu PHOENIX, która zakłada transformacje PET do GA z jednoczesną produkcją propanolu z C02, który może być wykorzystywany jako paliwo w silnikach diesla.

3

Od wizji do przełomu: radiofarmaceutyki w Instytucie Chemii i Techniki Jądrowej

Łyczko Monika, Koźmiński Przemysław

Postępy Techniki Jądrowej

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2025

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z. 3

25--32

PL

Instytut Chemii i Techniki Jądrowej należy do wiodących ośrodków badawczych w Polsce oraz cenionych jednostek na arenie międzynarodowej w zakresie badań nad radiofarmaceutykami. Prowadzone prace badawczo-rozwojowe obejmują projektowanie, syntezę oraz znakowanie biologicznie czynnych cząsteczek izotopami promieniotwórczymi. Badania koncentrują się na opracowywaniu radiofarmaceutyków przeznaczonych do celowanej diagnostyki i terapii, głównie w onkologii. Wykorzystanie zaawansowanej aparatury oraz współpraca interdyscyplinarnego zespołu specjalistów tworzy rozwiązania, które mogą realnie poprawić jakość i skuteczność leczenia pacjentów. Artykuł przedstawia fascynującą drogę, jaką przeszły badania nad radiofarmaceutykami w Instytucie – od pierwszych, stosunkowo prostych kompleksów chemicznych, po nowoczesne, wyspecjalizowane radiopreparaty podawane pacjentom w diagnostyce i terapii.

EN

The Institute of Nuclear Chemistry and Technology is one of Poland’s leading research centers and a respected institution on the international stage in the field of radiopharmaceutical research. Its research and development activities include the design, synthesis, and labelling of biologically active molecules with radioactive isotopes. The studies focus on developing radiopharmaceuticals for targeted diagnostics and therapy, mainly in oncology. By combining advanced instrumentation with the expertise of an interdisciplinary team, the Institute develops solutions that can genuinely improve the quality and effectiveness of patient treatment. The article presents the fascinating journey of radiopharmaceutical research at the Institute of Nuclear Chemistry and Technology – from the earliest, relatively simple chemical complexes to today’s modern, specialized radiopreparations administered to patients for diagnostics and therapy.

4

PET composites and their applications in the face of green chemistry challenges - an overview

Ostrowski Krzysztof Adam, Spyrowski Mariusz, Romańska Paulina, Majka Tomasz M., Piech Radosław, Zawadzka Zuzanna, Furtak Kazimierz, Bednarowski Dariusz

Polimery

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2025

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Vol. 70, nr 4

227--239

EN

The review discusses the recycling of PET packaging, highlighting its significance in the circular economy. It presents methods for processing the recovered material and its potential applications in various sectors of the economy. The importance of the 6R principle in integrating the economy and promoting sustainable development is also emphasized.

PL

W artykule omówiono recykling opakowań PET, podkreślając jego znaczenie w gospodarce obiegu zamkniętego. Przedstawiono metody przetwórstwa odzyskanego materiału i jego potencjalne zastosowania w różnych sektorach gospodarki. Wykazano znaczenie zasady 6R w integracji gospodarki i promowaniu zrównoważonego rozwoju.

5

Recykling taśmy podkładowej papierowej i PET

Wilczyńska-Zuchora Agnieszka

Kierunek Farmacja

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2025

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nr 2

62--64

PL

Recykling taśmy podkładowej papierowej oraz PET z etykiet w przemyśle farmaceutycznym stanowi istotny krok w kierunku zrównoważonego rozwoju. Pomimo wyzwań technologicznych, inwestycje w nowe metody przetwarzania tego materiału mogą przyczynić się do zmniejszenia ilości odpadów oraz zwiększenia efektywności surowcowej.

6

Studies of Attenuation Effects in Two- and Three-Photon Positronium Decays in Phantom Models

Kasperska Kamila, Skurzok Magdalena, Moskal Paweł

Bio-Algorithms and Med-Systems

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2025

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Vol. 21, Special issue: New Trends in Nuclear and Medical Physics

42--51

EN

Objective: Positron emission tomography (PET) enables non-invasive imaging of metabolic processes. Standard PET reconstructs radiotracer distribution using two back-to-back photons from electron-positron annihilation. However, about 0.3-0.5% of annihilations result in the creation of three photons. Three photons may be created in direct annihilation and in annihilation via the formation of metastable ortho-positronium carrying additional information not used by conventional PET. The Jagiellonian-PET (J-PET) detector allows us to use this information by applying positronium imaging based on the ortho-positronium (o-Ps) lifetime or the 3γ/2γ decay ratio. Accurate tomographic images require attenuation correction. This study investigates photon absorption in phantom models to form a basis for future attenuation maps for three-gamma decays. Methods: Monte Carlo (MC) simulations in ROOT and Geant4 Application for Tomographic Emission (GATE) were performed for water sphere, cylinder, a simplified head model and the mesh50_XCAT phantom. Both para-positronium (p-Ps) and o-Ps decays were simulated as uniformly distributed sources. Absorption probabilities were calculated by checking whether any photon in a multiplet interacted within the phantom. Emission- point-specific absorption maps were generated for all models. Toy MC and GATE simulations showed good overall agreement. Results: Photon triplets from o-Ps decays experienced higher absorption than photon pairs from p-Ps due to lower individual energies and higher attenuation. Absorption maps showed the dependence of photon survival probability on the decay location. In the mesh50_XCAT phantom, 24.9% of p-Ps pairs and 10.3% of o-Ps triplets escaped without interaction. Conclusions: Gamma absorption depends strongly on positronium decay mode and location, with o-Ps events experiencing higher attenuation. The generated absorption maps provide the first step toward dedicated attenuation correction for three-gamma positronium imaging, enabling accurate reconstruction in novel 3γ/2γ positronium imaging technique. The study presented indicates that the absorption of 3γ in the head is only about 2.5 times higher than for 2γ, which is encouraging for further development of the 3γ/2γ rate ratio imaging.

7

Effect of surface charge and gap distance on electroadhesive forces in electret films

Czapka Tomasz, Pelesz Adam

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 11

414--428

EN

Electroadhesion (EA) is the phenomenon of surface adhesion caused by electrostatic attraction due to electric fields, whether externally applied or originating from quasi-permanent surface charges (i.e., passive EA). In our study, the adhesion force is provided by the charges stored in the electret polyethylene terephthalate (PET) film. This study provides a clear and quantitative understanding of how a PET electret film behaves as a passive electroadhesive material. The tested film is charged via direct-current corona discharge (point-plane electrode configuration, ±10 kV) to impart a quasi-permanent surface charge. Key charge-storage characteristics (including surface potential distribution and charge decay time) are measured. This characterization revealed a non-uniform (bell-shaped) surface potential profile and long charge storage time on the PET film (t95% > 980 s). Next, the electrostatic adhesion force between the charged film and a grounded conductive surface is quantified at various film-surface separations (0.5 mm to tens of millimeters) using a precision force measurement setup. The attractive force increases with the film’s surface charge and decreases steeply with increasing separation distance, reaching approximately 16.6 mN at a 0.5 mm separation (corresponding to a surface charge density of about 4.2 mC/m²). These results demonstrate the feasibility of corona-charged PET as a low-power electroadhesive material.

8

Durability of ITO/Ag-alloy/ITO films on pet substrate under extended bending stress at various temperature and humidity conditions

Mohammed D. W., Ameen R. B., Bowen J., Sierros Konstantinos A., Kukureka S. N.

Advances in Materials Science

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2025

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Vol. 25, nr 2(84)

36--51

EN

Flexible electronic devices, such as OLEDs, flat panel displays (FPDs), and photovoltaic solar cells, frequently employ transparent conductive electrodes composed of indium tin oxide (ITO)/Ag-alloy/ITO-coated polymer films. However, the films are subjected to a combination of thermal and mechanical forces, particularly bending around rolls, during roll-to-roll manufacturing. This can result in thin film failure. Furthermore, these films are curved around the surface of flexible electronic devices, such as solar cells, during operation. Furthermore, they can be in service in hot and humid locations for extended periods throughout the summer, such as deserts. These stresses can lead to the degradation of the device's performance by causing cracks in the conductive thin films and corrosion of the Ag-alloy layer over time. In this work, ITO/Ag-alloy/ITO films were bent under tensile mode to different radius of curvature over a period of time at different humidity and temperature levels. The electrical resistance was measured in situ, and four combinations of temperature and relative humidity were used: 25°C, 65°C, and 25 percent and 80 percent. According to the results, irrespective of the temperature level, high humidity causes the films to degrade more quickly. Particularly, the films exhibited a notable increase in normalized electrical resistance when subjected to a 4.3 mm radius of curvature in both high temperature and high humidity conditions. This was associated to aggregation of the silver layer, film buckling, and crack formation. Furthermore, the film's conductivity was further reduced by surface cracks that allowed oxygen and moisture to penetrate. Consequently, to maintain the integrity of the film, an external applied stress with moisture and/or harsh environments as well as moisture and/or harsh environments alone should be avoided during both manufacturing and application processes.

9

Mechanical wave damping research in innovative solutions for concrete masonry units

Adamczyk Izabela, Major Maciej, Kalinowski Jarosław

Materiały Budowlane

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2024

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nr 8

54--61

EN

The article presents a new type of APS (openwork masonry unit) and WAPS (filled openwork masonry unit) concrete masonry units with a frame made of concrete modified with recycled materials. The technical data of the developed masonry unit and the composition of concrete modified with a mixture of SBR (styrene butadiene rubber) and PET (polyethylene terephthalate) recycling additives, as well as the composition of the composite damping mixture based on these two materials, are given. In order to demonstrate the effectiveness of the developed solution in reducing mechanical vibrations, the influence of the impact of different mechanical wave frequencies on the developed APS and WAPS concrete masonry units was assessed. The test results were presented graphically and showed that filling the holes of a new type of concrete masonry unit with a recycled composite mixture improves its effectiveness in limiting the propagation of mechanical waves in the analyzed range from 8 to 5000 Hz, simultaneously allowing the effective management of recycled materials.

PL

W artykule przedstawiono nowego typu betonowe murowe elementy ścienne APS (ażurowy pustak ścienny) i WAPS (wypełniony ażurowy pustak ścienny) o szkielecie wykonanym z betonu modyfikowanego materiałami recyklingowymi. Podano dane techniczne opracowanego elementu ściennego i skład betonu modyfikowanego mieszanką dodatków recyklingowych SBR (styrene butadiene rubber) i PET (politereftalan etylenu) oraz skład kompozytowej mieszanki tłumiącej powstałej na bazie tych dwóch materiałów. W celu wykazania efektywności opracowanego rozwiązania w redukcji drgań mechanicznych dokonano oceny wpływu oddziaływania różnych częstotliwości fali mechanicznej na opracowane betonowe murowe elementy ścienne APS i WAPS. Wyniki badań przedstawiono graficznie i wykazano, że wypełnienie otworów nowego typu betonowego murowego elementu ściennego recyklingową mieszanką kompozytową poprawia jego efektywność w ograniczeniu propagacji fal mechanicznych w analizowanym zakresie od 8 do 5000 Hz, pozwalając jednocześnie skutecznie zagospodarowywać materiały pochodzące z recyklingu.

10

First PET Studies of a FLASH Proton Beam: Summary and Future Prospects

Cesar John P., Abouzahr Firas, Crespo Paulo, Gajda Michael, Kuo Alex, Mawlawi Osama, Morozov Andrey, Ojha Aryan, Poenisch Falk, Proga Marek, Sahoo Narayan, Seco Joao, Takaoka Takeshi, Tavienier Stefan, Titt Uwe, Wang Xiaochun, Zhu Xiaorong, Lang Karol

Bio-Algorithms and Med-Systems

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2024

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Vol. 20, Special issue

49--54

EN

Objectives: Proton therapy, while highly effective and successful, still lacks a key feature: the ability to assess, in-vivo, the dose and end-point location of irradiations. Known as proton range verification, this capability can be realized by incorporating positron emission tomography (PET) systems in both conventional and emerging modalities, such as FLASH proton therapy. FLASH itself may revolutionize radiation oncology with its purported ability to better spare healthy tissues, but only if the underlying mechanisms can be understood. We summarize our work towards establishing in-beam PET modalities and elucidating the mystery of the FLASH effect. Materials: We've developed a PET scanner designed for live, in-beam imaging during therapeutic proton irradiations that can use short-lived positron emitting species (PES) activated by the beam to validate the range and dose of proton depositions. This scanner is made up of PET modules consisting of arrays of LYSO (lutetium-yttrium oxyorthosilicate) scintillating crystals coupled one-to-one to silicon photomultiplier (SiPM) arrays. These modules are readout by electronics based on the TOFPET2 ASIC platform from PETsys Electronics. Methods: Our collaboration with MD Anderson Cancer Center has given us opportunities to take real in-beam data using a non-clinical beamline capable of delivering FLASH proton irradiations into target phantoms made of polymethyl methacrylate (PMMA), high density polyethylene (HDPE), and water. Data collected both during and afterirradiations were used to perform novel analyses and to reconstruct images of PES activity due to the beam. Results: Exploratory studies, using a subset of our PET scanner, have demonstrated successful data acquisition during and after FLASH beam spills including quantitative imaging and dosimetry of activated phantoms. The full results, explored in this work, are highly promising and prove that in-beam PET can deliver on its goals. Upcoming experiments conducted using both FLASH and conventional beams will employ the full PET scanner and involve a rich experimental program with novel ideas for irradiation targets, beam characterization, and in-depth comparisons of the two irradiation modalities. Conclusions: This work demonstrates the unprecedented proof-of-principle for the capabilities of an in-beam PET scanner for imaging and dosimetry of both conventional and FLASH proton beams. These results open a new PET modality with proton beams which is particularly attractive for FLASH therapy but can serve effectively all proton irradiations, leading to improved treatment monitoring and image-guided therapy.

11

Development of correction techniques for the J-PET scanner

Das Manish, Bayerlein Reimund, Sharma Sushil, Parzych Szymon, Niedzwiecki Szymon, Badawi Ramsey D., Beyene Ermias Yitayew, Chug Neha, Curceanu Catalina, Czerwiński Eryk, Eliyan Kavya V., Głowa Bogusław, Hubalewska-Dydejczyk Alicja, Kacprzak Krzysztof, Kaplanoglu Tevfik, Kasperska Kamila, Korcyl Grzegorz, Khreptak Aleksander, Kubat Karol, Kumar Deepak, Lisowski Edward, Lisowski Filip, Mędrala-Sowa Justyna, Moyo Simbarashe, Mryka Wiktor, Opalińska Marta, Pandey Piyush, Rädler Martin, Skurzok Magdalena, Sowa-Staszczak Anna, Spencer Benjamin A., Tanty Pooja, Ardebili Keyvan Tayefi, Venadan Anoop K., Perez del Rio Elena, Stępień Ewa Ł., Moskal Paweł

Bio-Algorithms and Med-Systems

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2024

|

Vol. 20, no. 1

101--110

EN

Objective: Positron emission tomography (PET) is a widely used medical imaging technique that allows for non-invasive imaging of metabolic processes. However, traditional PET scanners rely on costly inorganic scintillators that limit their accessibility, especially in light of emerging long axial field-of-view devices. The modular J-PET scanner, an innovative alternative, uses 50-cm-long plastic scintillator strips, offering a cost-effective and modular solution. In this study we develop and assess the PET data correction techniques required for quantitative image reconstruction. Methods: We present methods for attenuation correction, random coincidence correction using the delayed time window (DTW) technique and scatter correction based on Monte Carlo simulations. Phantom studies using the NEMA IQ phantom were performed to qualitatively evaluate these corrections. Results: The results demonstrate that our implemented corrections for attenuation and random and scattered coincidences successfully improve the uniformity of tracer distribution in homogenous volumes and significantly reduce undesired activity in cold regions. Despite limitations in sensitivity and axial resolution, the applied correction techniques effectively enhance image quality, providing promising results for future applications. Conclusions: These findings highlight the potential of the modular J-PET system to offer affordable PET imaging and to pave the way for a total-body PET scanner based on plastic scintillators. Future work will focus on quantitative validation and the implementation of these corrections for human subject imaging.

12

A vision to increase the availability of PET diagnostics in low- and medium-income countries by combining a low-cost modular J-PET tomograph with the 44Ti/44Sc generator

Moskal Paweł, Stępień Ewa, Khreptak Aleksander

Bio-Algorithms and Med-Systems

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2024

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Vol. 20, Special issue

55--62

EN

Objectives: This paper presents the prospects for increasing the availability of PET diagnostics by combining low-cost, lightweight and easily portable modular J-PET with the 44Ti/44Sc generator. Methods: J-PET is constructed based on the low-cost axially arranged plastic scintillators that may enable the construction of PET scanners 5 to 10 times less expensive compared to current PET systems, which are based on crystal scintillators. Development of the radionuclide 44Ti/44Sc generator with the 60-year half-lifetime would enable long-term onsite production of 44Sc labelled radiopharmaceuticals, eliminating the need for extensive and costly infrastructure typically associated with nuclear medicine. Presently applied 68Ge/68Ga generators with the 270 days half- -lifetime require renewal every year. The 44Ti/44Sc generator could, in principle, be purchased once every half century. Results: The lightweight and portable J-PET scanner, combined with the 44Ti/44Sc generator, can be deployed in remote and underserved regions, thus democratising access to advanced medical-imaging techniques. Conclusions: This novel concept shows the transformative potential of combining innovative J-PET technology with the 44Ti/44Sc generator to make advanced diagnostics more accessible and affordable worldwide, especially benefiting millions of patients in low- and medium-income countries, and driving further innovations in medical imaging.

13

Selected Properties of Reinforcing Composite Bars for Concrete Elements Prepared from Waste Polyethylene Terephthalate (PET) Bottles

Katzer Jacek, Grzybowski Paweł, Kobaka Janusz

Rocznik Ochrona Środowiska

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2023

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Tom 25

188--197

EN

A concept of producing reinforcing bars for concrete elements from waste polyethylene terephthalate (PET) bottles is presented in the paper. The proposed technology of production harnesses strips of PET cut from bottles and thermal treatment. Finally, a sand-resin coating is applied to the composite bars. Produced bars can be differentiated by utilising different numbers of strips influencing the diameter of a bar. The key mechanical properties of the bars containing 3 to 8 strips were tested during the research program. Maximum loadings and displacements were established. Problems regarding the future application of the bars in question were discussed. Areas of need for further research were pointed out.

14

The influence of the electrode material on the dielectric properties of PET films

Łowkis Bożena, Ziaja Jan, Kraft Aleksandra Anna

Przegląd Elektrotechniczny

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2023

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R. 99, nr 1

58--61

EN

This paper presents the influence of the measuring electrode material on the dielectric properties of polyethylene terephthalate. We show that volume resistivity, surface resistivity, relative permittivity and the dielectric loss factor of PET films are a function of the electrode material used. We also evaluate the effect of thermal aging on the tested material parameters.

PL

Przedstawiono wpływ materiału elektrod pomiarowych na właściwości dielektryczne politereftalanu etylenu. Stwierdzono, że rezystywność skrośna, rezystywność powierzchniowa, względna przenikalność elektryczna oraz współczynnik strat dielektrycznych folii PET są funkcją zastosowanego materiału elektrod. Oceniono wpływ starzenia termicznego na badane parametry materiałowe.

15

Performance of 2D photonic crystal fiber on optical waveguide algorithm

Karamifard Mozhdeh, Garoosi Hamed, Hosseini-Jebelli Seyed Mahdi

Przegląd Elektrotechniczny

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2023

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R. 99, nr 11

170--174

EN

The photonic crystal fibers (PCFs) are designed based on optical material by periodic changes in its dielectric constant, in which a wide platform of applications in numerous domains has been provided. Many optical communication devices that are designed on the PCFs have reported high throughput in their showing, by making a significant contribution in compactness, miniature sizes and fast switching, which compose of alternate high and low refractive index materials. In this study, the PCF and the effects of translational symmetry on their properties are introduced. Two dimensional photonic crystals (2D-PC) are studied in detail, and a new method for scattering photons off finite and infinite PCFs is developed. In this regard, the conventional fabrication methods of PCFs have been studied and a new technique for vertical etching of Polyethylene Terephthalate (PET) by ultraviolet radiation has been introduced as a powerful and economical method to implement these structures. Also, the potential of the method for fabricating higher precision and smaller dimensions has been examined. To ensure the accuracy of the proposed method, simulation was carried out using Matlab software, in which the magnitude of the light source and then the angular impact of the UV irradiation beams are investigated. In this study, the finite difference time domain (FDTD) method is accomplished for analysis of photonic-band gap (PBG) -based polarization.

PL

Światłowody fotoniczne (PCF) są projektowane w oparciu o materiał optyczny poprzez okresowe zmiany jego stałej dielektrycznej, co zapewnia szeroką platformę zastosowań w wielu dziedzinach. Wiele optycznych urządzeń komunikacyjnych zaprojektowanych na PCF odnotowało wysoką przepustowość podczas ich wyświetlania, wnosząc znaczący wkład w zwartość, miniaturowe rozmiary i szybkie przełączanie, które składają się z naprzemiennych materiałów o wysokim i niskim współczynniku załamania światła. W tym badaniu przedstawiono PCF i wpływ symetrii translacyjnej na ich właściwości. Szczegółowo badane są dwuwymiarowe kryształy fotoniczne (2D-PC) i opracowywana jest nowa metoda rozpraszania fotonów na skończonych i nieskończonych PCF. W związku z tym zbadano konwencjonalne metody wytwarzania PCF i wprowadzono nową technikę pionowego trawienia politereftalanu etylenu (PET) za pomocą promieniowania ultrafioletowego jako wydajną i ekonomiczną metodę wdrażania tych struktur. Zbadano również potencjał metody do wytwarzania wyrobów o większej precyzji i mniejszych gabarytach. Aby zapewnić dokładność proponowanej metody, przeprowadzono symulację z wykorzystaniem oprogramowania Matlab, w którym bada się wielkość źródła światła, a następnie kątowe oddziaływanie wiązek promieniowania UV. W tym badaniu metoda domeny różnic skończonych w dziedzinie czasu (FDTD) została wykorzystana do analizy polaryzacji opartej na fotonicznej przerwie wzbronionej (PBG).

16

Pozytonowa tomografia emisyjna (PET) – zastosowanie radioizotopów alternatywnych do fluorodeoksyglukozy (18F)

Cichoń Katarzyna, Ptaszyńska Anna, Chlewicki Wojciech, Supińska Aleksandra

Inżynier i Fizyk Medyczny

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2023

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Vol. 12, nr 4

329--334

PL

Metoda pozytonowej tomografii emisyjnej to jedna z technik obrazowania stosowana w medycynie nuklearnej. W celu prawidłowego wykonania badania techniką PET pacjent przyjmuje związek chemiczny oznakowany izotopem, który jest zdolny do emisji pozytonów. Najpopularniejszym radiofarmaceutykiem stosowanym w PET jest fluorodeoksyglukoza (FDG) – analog glukozy znakowany przez fluor 18F. Obserwuje się kumulację radiofarmaceutyku w narządach, które intensywnie metabolizują glukozę (np. serce, mózg), w tym również w zmianach nowotworowych. W pracy zostały przedstawione alternatywne do fluorodezoksyglukozy radioizotopy, takie jak: 11C, 68Ga, 124I. Nowa era radioizotopów opisanych w niniejszej pracy oraz postęp technologiczny – systemy PET/CT lub PET/MRI pozwalają na uzyskanie lepszych rezultatów zarówno w zakresie diagnostyki, jak i ochrony pacjenta przed promieniowaniem jonizującym.

EN

The positron emission tomography method is one of the imaging techniques used in nuclear medicine. In order to perform the PET examination correctly, the patient accepts a chemical compound marked with an isotope that is capable of positron emission. The most popular radiopharmaceutical used in PET is fluorodeoxyglucose (FDG) – it is a glucose analogue marked by fluorine 18F. Accumulation of a radiopharmaceutical in organs intensively metabolizing glucose (eg heart, brain), including in neoplastic lesions, is observed. In f this work are presented radioisotopes, such as: 11C, 68Ga, 124I, which are alternative to fluorodezoxyglucose. The new era of radioisotopes described in the paper and progress in technology – PET/CT PET/ MRI systems, give better results in diagnostics and better radiation protection- less exposure to ionizing radiation are gained for the patient.

17

Utilizing Pyrolysis of Plastic Debris for Refuse-Derived Fuel Production and Viable Substitute to Wood Debris

Mutiara Sari Mega, Inoue Takanobu, Harryes Regil Kentaurus, Septiariva Iva Yenis, Yokota Kuriko, Notodarmodjo Suprihanto, Kato Shigeru, Al Ghifari Rizal Muhammad, Suhardono Sapta, Suryawan I. Wayan Koko, Prayogo Wisnu, Arifianingsih Nur Novilina

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 8

133--142

EN

This research explores the viability of converting discarded Polyethylene Terephthalate (PET) plastic waste into a valuable resource through the implementation of pyrolysis and refuse-derived fuel (RDF) technologies. The objective is to assess the potential of PET charcoal waste as an efficient source for RDF generation, surpassing the energy recovery and recycling potential of PET waste. The study introduces three RDF variants: RDF PET100, RDF PET50, and RDF PET0. RDF PET100 is comprised entirely of PET charcoal, RDF PET50 combines 50% PET charcoal with 50% wood debris, and RDF PET0 consists entirely of wood debris. Comprehensive assessments of water content, ash content, and calorific value were conducted to evaluate the quality of these RDF formulations. Results indicate that RDF PET100 exhibits a water content of 2.63%, ash content of 0.73%, and calorific value of 5,976 MJ/kg. Similarly, RDF PET50 showcases a water content of 3.6%, ash content of 1.05%, and calorific value of 5,587 MJ/kg. RDF PET0 presents a water content of 7.51%, ash content of 1.36%, and calorific value of 4,198 MJ/kg. The outcomes underline the potential of PET plastic waste repurposing through RDF and pyrolysis techniques. Particularly, RDF PET100 emerges as a high-caliber fuel option characterized by its minimal water and ash content, coupled with a substantial calorific value. This innovation holds promise in mitigating plastic waste challenges, particularly pertinent in the context of Indonesia.

18

Lekkie kruszywo ultrakompozytowe - idea ekologicznego i użytecznego wykorzystania odpadów mineralnych i sztucznych jako składnika betonu

Górak Piotr, Postawa Przemysław

Drogownictwo

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2023

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nr 2-3

52--58

PL

W artykule przedstawiono wyniki prac projektowych i badawczych, których celem było wytworzenie lekkiego kruszywa ultrakompozytowego (UCLA - ultracomposite lightweight aggregate) w rezultacie połączenia odpadów pochodzących z różnych strumieni. W wyniku procesu odpowiednio przeprowadzonej obróbki termicznej w specjalnie zaprojektowanych warunkach, wytworzono kompozyt w postaci granulek odpowiadających frakcji kruszywowej 2-8 mm. Uzyskano różne rodzaje kruszyw lekkich wykonanych przy użyciu różnych drobnoziarnistych wypełniaczy mineralnych, których podstawowe właściwości zostały zbadane i zaprezentowane. Dodatkowo zostały wykonane wstępne badania aplikacyjne tych kruszyw w funkcji składnika kompozytu betonowego. Badania przeprowadzono na zmodyfikowanych zaprawach normowych powszechnie wykonanych według zaleceń normy PN-EN 196-1, gdzie 25% objętości piasku normowego zostało zastąpione sztucznym kruszywem ultrakompozytowym.

EN

In this article authors presented research and project results which target was production of lightweight aggregates as a result of connect waste from different sources. During works about process and technology production new ecological aggregate was used physical properties of polymers and their high viscosity in phase of melting. As a result of thermal treatment in special production conditions was created composite in the granules shape. Obtained coarse aggregates 2/8 mm based on different waste mineral filler. All aggregates was tested in basic properties scope and presented. Additionally preliminary application tests those aggregates was made like function of concrete’s ingredient. The research were carried out on modified standard mortars commonly made according to the recommendations of the PN-EN 196-1 standard, where 25% of the volume of standard sand was replaced with artificial ultra-composite aggregate.

19

Exploration of simultaneous dual-isotope imaging with multiphoton modular J-PET scanner

Beyene Ermias Y., Das Manish, Durak-Kozica Martyna, Korcyl Grzegorz, Mryka Wiktor, Niedźwiecki Szymon, Parzych Szymon, Tayefi Keyvan, Walczak Rafał, Wawrowicz Kamil, Stępien Ewa, Moskal Pawel

Bio-Algorithms and Med-Systems

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2023

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Vol. 19, no. 1

101--108

EN

The modular J-PET scanner, comprising 24 compact and versatile modules, each consisting of 13 plastic strips with four SiPM detectors at the ends, represents a powerful tool for clinical applications in nuclear medical imaging. This study presents preliminary results from the exploration of simultaneous dual-isotope imaging using the modular J-PET system. Our approach involved two isotopes: 68Ge, characterized by a ringlike shape, and 22Na, exhibiting a point-like shape. The imaging was based on double-coincidence and triple-coincidence events. In the double coincidence case, both isotopes contributed comparably, whereas in the triple coincidence case 22Na dominated due to the prompt gamma being emitted with 100% of positron emissions, unlike 68Ga, where the prompt gamma was emitted in only 1.3% of cases after positron emission. In this work we present direct 2γ images determined for two-signal events and images for three-signal events, with two signals from annihilation photons and one from a prompt gamma. These results showcase the preliminary findings from simultaneous dual-isotope imaging of 68Ga and 22Na isotopes using the modular J-PET scanner, which will be presented and discussed.

20

Estimating the efficiency and purity for detecting annihilation and prompt photons for positronium imaging with J-PET using toy Monte Carlo simulation

Das Manish, Mryka Wiktor, Beyene Ermias Y., Parzych Szymon, Sharma Sushil, Stępień Ewa, Moskal Paweł

Bio-Algorithms and Med-Systems

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2023

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Vol. 19, no. 1

87--95

EN

The positronium imaging technique represents a potential enhancement of the PET imaging method. Its core principle involves employing a β+ radiation source that emits additional gamma (γ) quanta referred to as prompt gamma. Our aim is to evaluate the capability to differentiate between annihilation and prompt gamma emissions, a vital aspect of positronium imaging. For this purpose, the selected isotopes should enable high efficiency and purity in detecting both prompt gamma and annihilation gamma. The assessment of the efficiency in identifying prompt and annihilation photons for various isotopes, which are potentially superior candidates for β++ γ emitters, is conducted through toy Monte-Carlo simulation utilizing the cross-section formula for photon-electron scattering. In this article, we have performed calculations for efficiency and purity values across different isotopes under ideal conditions and examined how these values evolve as we incorporate the fractional energy resolution into the analysis. Ultimately, the primary goal is to determine the energy threshold that optimizes both efficiency and purity, striking a balance between accurately identifying and recording events of interest while minimizing contamination from undesired events.