Effect Of Irradiation Research Articles

Influence of Gamma-Ray Irradiation on Polystyrene Food Container Weathering

Conventional plastics, such as polystyrene (PS), are widely used due to their high degradation stability, which makes them suitable for various applications. However, the downside of this property is that it results in the persistence of these plastics in the environment, contributing to plastic pollution. This paper investigated the effects of gamma-ray irradiation on the mechanical, optical, structural, thermal, and morphological properties of PS food containers subjected to natural (NW) and artificial weathering (AW). First, the PS films were exposed to a source of 60Co-γ at doses of 0, 10, and 45 kGy, and then they were subjected to NW for 0-190 days and AW for 0-500 hours. The mechanical properties of the PS films (tensile strength and elongation at break) were evaluated under NW and AW conditions, revealing an acceleration factor (AF) ranging from 3.8 to 6.2. According to the results, gamma-irradiation had a complex and uneven effect on the physicochemical properties of the weathered PS films. The type of weathering and conditions under which the exposures were performed, in conjunction with the irradiation doses, provided a comprehensive analysis of the effects of gamma-ray irradiation on PS food containers. These results are relevant for extending PS food containers' longevity rather than increasing their degradation.

Irradiation effects on GEM detectors operated at RUN1 and RUN2 at the LHCb experiment

Triple-GEM detectors with pad readout have been employed to equip the innermost region (R1) of the first station (M1) within the Muon system of the LHCb experiment. The GEM detectors have been operated with an Ar/CO2/CF4 = 45/15/40 gas mixture at a gas gain of about 4000 with an average particle flux of about 250 kHz/cm2. Throughout RUN1 and RUN2, spanning approximately 440 days of colliding beams, the GEM detectors accumulated a charge of up to 0.5 C/cm2. This paper presents a comparative analysis between a global irradiation test of GEM detectors at the Calliope facility (ENEA-Casaccia, 1.25 MeV γ ray flux from a 60Co source) and the GEMs operated at LHCb, focusing on the impacts of a CF4-based gas mixture. In both instances, the detectors were opened and the GEM foils were examined by the EN-MME-MM CERN group with a Field Emission Gun Scanning Electron Microscope (FEG-SEM) for a magnified image analysis and an X-Max Energy Dispersive X-ray Spectroscopy (EDS) for the chemical one.

Irradiation effects on copper oxide superconductors including high-entropy REBCO(HE-REBCO)

Polycrystalline specimens of copper oxide superconductors YBa2Cu3O7-δ(YBCO), Y0.39Sm0.30Eu0.31Ba2Cu3O7-δ(ME-REBCO), Y0.18La0.24Nd0.14Sm0.14Eu0.15Gd0.15Ba2Cu3O7-δ (HE-REBCO) were irradiated with 1 MeV-He ions at room temperature. Magnetization measurement using superconducting quantum interference device (SQUID) and microstructure observation using transmission electron microscope (TEM) were conducted before and after irradiation. The improvement of properties in HE-REBCO and degradations in YBCO, ME-REBCO were suggested by SQUID measurement. HE-REBCO had smaller irradiation defects and volume fractions although disappearance of twin boundaries due to tetragonal transition occurred in peak-damage area as well as YBCO. These defects work as optimal flux pinning centers leading to improve properties in HEREBCO.

Corrosion of 316L stainless steel in high temperature water and steam: effects of simultaneous proton irradiation

316L stainless steel was exposed to 320 °C hydrogenated water and 480 °C hydrogenated steam for 24 h and 72 h while simultaneously irradiated with 5.4 MeV protons to yield a damage rate of 7 × 10–7 dpa/s. Oxide films characterized in cross-section STEM revealed chemical and morphological differences. High levels of radiolysis in water resulted in significantly reduced corrosion rates while inducing dissolution of the inner oxide layer, whereas in steam the effects of radiolysis are insignificant. Conversely, displacement damage effects are negligible in water but significantly increase the corrosion rate in the steam condition through the growth of inner oxide porosity.

Effect of gamma irradiation on the proteogenome of cold-acclimated Kocuria rhizophila PT10

In this paper, we investigated the effects of ionizing radiation (IR) on the protein dynamics of cold-stressed cells of a radioresistant actinobacterium, Kocuria rhizophila PT10, isolated from the rhizosphere of the desert plant Panicum turgidum using a shotgun methodology based on nanoflow liquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS). Overall, 1,487 proteins were certified, and their abundances were compared between the irradiated condition and control. IR of cold-acclimated PT10 triggered the over-abundance of proteins involved in (1) a strong transcriptional regulation, (2) amidation of peptidoglycan and preservation of cell envelope integrity, (3) detoxification of reactive electrophiles and regulation of the redox status of proteins, (4) base excision repair and prevention of mutagenesis and (5) the tricarboxylic acid (TCA) cycle and production of fatty acids. Also, one of the more significant findings to emerge from this study is the SOS response of stressed PT10. Moreover, a comparison of top hits radio-modulated proteins of cold-acclimated PT10 with proteomics data from gamma-irradiated Deinococcus deserti showed that stressed PT10 has a specific response characterised by a high over-abundance of two transcriptional regulators, NemA, GatD, and UdgB.

Germanium nanostructures by helium plasma irradiation

The effects of helium plasma irradiation, which has been widely studied on metals, on germanium have been experimentally investigated. The irradiation temperature ranges from 430 to 720 K, and the incident ion energy ranges from 30 to 100 eV. From the scanning electron microscope (SEM) observation, it was found that various morphological changes including pits, nanocones, nanopillars, and roughened surfaces occur. The spatial scale of the morphological change was analyzed by applying fast Fourier transform to SEM micrographs. Thermal desorption spectroscopy analysis suggests that He atoms implanted on Ge play major roles in forming roughened surfaces at a surface temperature higher than 500 K.

Effects of electron beam irradiation on microbial load, physicochemical properties, sensory quality, stability of active components, and antioxidant activity of Platycodon grandiflorum (Jacq.) A. DC.

Platycodon grandiflorum (Jacq.) A. DC. (PG) is an edible and medicinal plant. This study aimed to investigate the potential of electron beam (EB) irradiation for preserving PG. EB Irradiation at doses of 2-8 kGy were applied to PG, and the effects on microbial content, sensory qualities, chemical qualities, and EB penetration were examined. Results showed that irradiation with 6 kGy effectively maintained PG's microbiological quality of PG when packing thickness was ≤ 6.3cm during a 360-day storage period. The physicochemical properties, color, active ingredient contents, and antioxidant capacities of PG remained unaffected. However, total flavonoid and Platycodin-D content exhibited a non-dose-dependent alteration. The use of electronic nose analysis successfully differentiated the odor of EB irradiated PG samples from non-irradiated ones. Fingerprint analysis also indicated no significant impact of EB irradiation on PG quality. These findings suggest that EB treatment could be a valuable approach for extending the shelf life of PG.

Exploring the impact of pre-existing helium bubbles on nanoindentation in tungsten through molecular dynamics simulation

Gaining insight into the underlying mechanisms driving nanoindentation-induced behavior in tungsten is essential for comprehending its mechanical properties. Although the plasticity of conventional pure tungsten under nanocontact conditions is well understood, these theoretical constructs may become inadequate when applied to irradiated tungsten due to the interplay between helium bubbles and dislocations. Here, we employed an integrated approach, combining crystal defect theories, molecular dynamics simulations, and machine learning, to explore the initiation and progression of dislocations in tungsten containing helium bubbles during nanoindentation, focusing on elucidating the impact of helium bubbles. In contrast to the typical dislocation nucleation in pure tungsten, the presence of helium bubbles mitigates local shear strain, thereby hindering dislocation nucleation and propagation, leading to a reduction of indentation force. Additionally, we conducted a comparative analysis between samples with and without helium bubbles, examining factors such as atomic displacement, strain localization parameters, dislocation line length, and stress component distribution. More importantly, a significant outcome of our study is the establishment of a relationship between the consistent alteration in the shape of helium bubbles and their size during micro-scale nanoindentation, achieved through machine learning techniques. Our findings reveal that the area occupied by helium bubbles post-nanoindentation is inversely correlated with indentation depth and directly linked to helium bubble size. These discoveries represent a notable advancement in understanding the effects of irradiation to a certain degree.

Microbiological and Imaging-Based Evaluations of Photodynamic Therapy Combined with Er:YAG Laser Therapy in the In Vitro Decontamination of Titanium and Zirconia Surfaces.

The oral cavity's soft and hard tissues create a conducive environment for microbial proliferation and biofilm development, facilitating the colonization of prosthodontic and implant materials such as titanium (Ti) and zirconia (Zr). This study aimed to compare the efficacy of conventional decontamination methodologies (i.e., chemical and mechanical, using 0.12% digluconate chlorhexidine (CHX) solution-treatment and airflow) to adjunctive laser-based interventions on Ti and Zr substrates inoculated with Staphylococcus (S.) aureus ATCC 25923. Additionally, this investigation sought to elucidate the impact of these treatments on temperature variations and surface integrity, analyzing the laser irradiation effects on these prevalent dental materials. Experimental configurations were delineated for both Ti and Zr samples across four groups: (1) a conventional treatment group (CV); (2) a photodynamic therapy group (PDT); (3) an Er:YAG laser treatment group (Er); (4) a combined PDT and Er:YAG treatment group (PDTEr). Also, a negative control group (C) that received no treatment was considered. The decontamination of the inoculated disc samples was evaluated by quantifying the microbial colonies in colony-forming units per milliliter (CFU/mL). Temperature variations on the surface of the samples were determined during laser treatments. Surface modifications were investigated using scanning electron microscopy (SEM) and optical coherence tomography (OCT). For statistical analysis, Fisher 95% confidence intervals, Hsu's MCB method, and the Kruskal-Wallis test were applied. With regard to the 105 CFU/mL of the negative control group, results indicated average values equal for each study group to (1) 2.66 CFU/mL for Ti and 2 CFU/mL for Zr for the CV group; (2) 0.33 CFU/mL for Ti and 1 CFU/mL for Zr for the PDT group; (3) 1.25 CFU/mL for Ti and 0 CFU/mL for Zr for the Er group; (4), and 0 CFU/mL for both Ti and Zr for the PDTEr group. Therefore, the combined PDT and Er:YAG treatment (PDTEr) and the singular PDT modality outperformed conventional decontamination methods in eradicating S. aureus biofilms from both Ti and Zr surfaces. Notably, the PDTEr regime achieved a comprehensive elimination of microbial colonies on treated substrates. Surface examination employing OCT demonstrated discernible alterations in the surface morphology of samples subjected to Er:YAG and combined PDT and Er:YAG treatments. Temperature checks during treatments showed no major changes, suggesting the applied laser methods are safe. In conclusion, PDTEr and PDT eliminated bacteria more effectively, but Zr surfaces were more resilient, making them better for microbe-controlling applications. Also, the study demonstrated that the (less costly but lower resolution) OCT method can replace SEM for such investigations.

Chemical evolution of complex organic molecules in turbulent protoplanetary discs: effect of stochastic ultraviolet irradiation

ABSTRACT We investigate the chemical evolution of complex organic molecules (COMs) in turbulent discs using gas-ice chemical reaction network simulations. We trace trajectories of dust particles considering advection, turbulent diffusion, gas drag, and vertical settling, for 10$^6$ yr in a protoplanetary disc. Then, we solve a gas-ice chemical reaction network along the trajectories and obtain the temporal evolution of molecular abundances. We find that the COM abundances in particles can differ by more than two orders of magnitude even when the ultraviolet (UV) fluence (i.e. the time integral of UV flux) received by the particles are similar, suggesting that not only the UV fluence but also the time variation of the UV flux does matter for the evolution of COMs in discs. The impact of UV fluence on molecular abundances differs between oxygen-bearing and nitrogen-bearing COMs. While higher UV fluence results in oxygen being locked into CO$_2$, leading to reduced abundances of oxygen-bearing COMs such as CH$_3$OCH$_3$, mild UV exposure can promote their formation by supplying the precursor radicals. On the other hand, nitrogen is not locked up into specific molecules, allowing the formation of nitrogen-bearing COMs, particularly CH$_3$NH$_2$, even for the particle that receives the higher UV fluence. We also find that the final COM abundances are mostly determined by the inherited abundances from the protostellar core when the UV fluence received by dust particles is less than a critical value, while they are set by both the inherited abundances and the chemistry inside the disc at higher UV fluence.

Effects of red-light irradiation and melatonininjection on the antioxidant capacity and occurrence of apoptosis in abalones (Haliotis discus hannai) subjected to thermal stress

High ocean temperatures caused by global warming induce oxidative stress in aquatic organisms. Melatonin treatment and irradiation using red light-emitting diodes (LEDs) have been reported to reduce oxidative stress in a few aquatic organisms. However, the effects of red LED irradiation and melatonin injection on the antioxidant capacity and degree of apoptosis in abalones, which are nocturnal organisms, have not yet been reported. In this study, we compared the expression levels of antioxidant enzymes, total antioxidant capacity, and the degree of apoptosis in abalones subjected to red LED irradiation and melatonin treatment. The results revealed that at high water temperatures (25 °C), the mRNA expression levels of the superoxide dismutase (SOD) and glutathione peroxidase (GPx) genes and the antioxidant activity of SOD decreased in abalones in the red-LED irradiated and melatonin-treated groups compared with those in abalones in the control group. Although high water temperatures induced DNA damage in the abalone samples, the degree of apoptosis was lower in the red-LED irradiated and melatonin-treated groups than in the control group. Overall, the abalones in the melatonin-treated and red-LED irradiated groups showed reduced oxidative stress and increased antioxidant enzyme levels under thermal stress compared with those in the control group. Therefore, red LED irradiation is a promising alternative to melatonin treatment, which is difficult to administer continuously for a long time, for protecting abalones from oxidative stress.

Protocol digest of a randomized phase III trial comparing S-1-based chemoradiotherapy with/without nivolumab for unresectable locally advanced or borderline resectable pancreatic cancer: JCOG1908E (PENETRATE)

Abstract Pancreatic cancer remains a highly lethal disease with a 5-year survival proportion of <10%. Chemoradiotherapy is a treatment option for unresectable locally advanced (UR-LA) or borderline resectable (BR) pancreatic cancer, but its efficacy is not sufficient. Induction of the synergistic effect of irradiation and immune checkpoint inhibitors can be an attractive strategy. An open-label randomized phase III trial has been conducted since October 2020 to confirm the superiority of nivolumab plus S-1-based chemoradiotherapy over S-1-based chemoradiotherapy alone in patients with UR-LA or BR pancreatic cancer. A total of 216 patients will be enrolled in 14 institutions within 3.5 years. The primary endpoint of the safety run-in part is dose-limiting toxicity, and that of the phase III part is overall survival. This trial was registered at the Japan Registry of Clinical Trials as jRCT2080225361 (https://jrct.niph.go.jp/latest-detail/jRCT2080225361).

Observation of therapeutic effect of lamp irradiation combined with purple gromwell oil gauze on alleviating intestinal colic in patients.

Intestinal colic is a common complication in patients who have undergone radical surgery for colorectal cancer. Traditional Chinese medicine has advantages, including safety and stability, for the treatment of intestinal colic. Lamp irradiation for abdominal ironing has been applied in the treatment of many gastrointestinal diseases. Purple gromwell oil has the effects of clearing heat, cooling blood, reducing swelling, and relieving pain. To investigate the impact of lamp irradiation combined with purple gromwell oil gauze on ameliorating intestinal colic in patients after radical surgery for colorectal cancer. A total of 120 patients who experienced postoperative intestinal colic complications after radical surgery for colorectal cancer and who were admitted to Foshan Traditional Chinese Medicine Hospital between June 2019 and March 2023 were enrolled as study subjects. The patients were divided into a control group (60 patients) and an observation group (60 patients) based on treatment method. The control group was treated with lamp irradiation, while the observation group was treated with lamp irradiation and external application of purple gromwell oil gauze. The clinical efficacy, Numeric Rating Scale (NRS) score, duration of symptoms, and rate of adverse reaction occurrence were further compared between the two groups. The general effective rate in the observation group was 95.00%, which was significantly higher than that in the control group (86.67%, P < 0.05). Before treatment, there was no significant difference in the duration of symptoms between the groups (P > 0.05). After 1, 2, 3, and 4 d of treatment, the duration of symptoms in both groups were decreased, and the duration in the observation group was significantly lower than that in the control group (96.54 ± 9.57 vs 110.45 ± 11.23, 87.26 ± 12.07 vs 104.44 ± 11.68, 80.45 ± 16.21 vs 99.44 ± 14.95, 73.18 ± 15.58 vs 92.17 ± 14.20; P < 0.05). After 1, 3, 5, and 7 d of treatment, the NRS scores in both groups were decreased, and the NRS scores in the observation group were significantly lower than those in the control group (3.56 ± 0.41 vs 4.04 ± 0.58, 3.07 ± 0.67 vs 3.74 ± 1.02, 2.52 ± 0.76 vs 3.43 ± 0.85, 2.03 ± 0.58 vs 3.03 ± 0.82; P < 0.05). There was no significant difference in the rate of adverse reaction occurrence between the groups (P > 0.05). The use of lamp irradiation combined with purple gromwell oil gauze in patients with intestinal colic after radical surgery for colorectal cancer can reduce symptom duration, alleviate intestinal colic, and improve treatment efficacy, and this approach is safe. It is worth promoting the use of this treatment in clinical practice.

Drosophila melanogaster как модель in vivo для оценки цитогенетических эффектов низкоинтенсивного ионизирующего излучения

The most important target of radiation damage is the cell nucleus. Structural and functional changes occurring in the nucleus under the influence of ionizing radiation affect the development of different biological effects at the cellular and organismal levels. In the present study, the Comet assay was used which makes it possible to assess the complex of DNA damage in different somatic cells of the body. The specificity of the cytogenetic effect of irradiation in low doses in Drosophila melanogaster has been established. The observed reactions depended not only on the irradiation dose and genotype but also on the type of DNA damage and tissue. In general, neuroblasts of individuals with low synthesis of cytoplasmic superoxide dismutase (sodn1/+) showed the highest sensitivity to irradiation in low doses. With an increase in the dose of ionizing radiation, the frequency of alkali-labile sites and DNA single-strand breaks in sodn1-genotype cells increased. The repair mutant genotypes, on the contrary, had radiosensitive traits exclusively at the level of DNA double-strand breaks. To a greater extent, an increase in the yield of radiation-induced DNA damage of this type was registered in cells of the imaginal disks of individuals with defect in the mechanisms of DNA double-strand break repair (okrA17-11/+), postreplicative repair, and meiotic recombination (mei-41D5/+). The genetically unstable strains used in the work have radiosensitive features which makes them convenient models for assessing the radioecological situation in the environment.

Natural Guardians: Natural Compounds as Radioprotectors in Cancer Therapy.

Cancer remains a significant global health challenge, with millions of deaths attributed to it annually. Radiotherapy, a cornerstone in cancer treatment, aims to destroy cancer cells while minimizing harm to healthy tissues. However, the harmful effects of irradiation on normal cells present a formidable obstacle. To mitigate these effects, researchers have explored using radioprotectors and mitigators, including natural compounds derived from secondary plant metabolites. This review outlines the diverse classes of natural compounds, elucidating their roles as protectants of healthy cells. Furthermore, the review highlights the potential of these compounds as radioprotective agents capable of enhancing the body's resilience to radiation therapy. By integrating natural radioprotectors into cancer treatment regimens, clinicians may improve therapeutic outcomes while minimizing the adverse effects on healthy tissues. Ongoing research in this area holds promise for developing complementary strategies to optimize radiotherapy efficacy and enhance patient quality of life.

Irradiation Effect in Thermoelectric Polymer Polyaniline Induced by High-Energy Electron Beam

A comprehensive investigation was conducted on the relationships between molecular structure, morphology and thermoelectric properties of HCl-doped polyaniline (PANi) nanorods subjected to 10[Formula: see text]MeV electron beam irradiation. Morphological and structural characterization revealed that the crystallinity of irradiated PANi nanorods remained almost unchanged, and minimal oxygen content was detected. This resulted in minimal alterations to the thermo-stability. In addition, the thermoelectric properties of PANi were enhanced. A maximum conductivity of 22.85[Formula: see text]S/cm was obtained at 50[Formula: see text]kGy, which was 1.46 times that of pristine PANi. Interestingly, the Seebeck coefficient reached a maximum of −3.56[Formula: see text][Formula: see text]V/K at 100[Formula: see text]kGy, indicating [Formula: see text]-type organic semiconductor properties. However, a peak power factor of 0.024[Formula: see text][Formula: see text]W[Formula: see text]m[Formula: see text] K[Formula: see text] was achieved with 60[Formula: see text]kGy irradiation, which was slightly enhanced compared to 0.018[Formula: see text][Formula: see text]W[Formula: see text]m[Formula: see text][Formula: see text]K[Formula: see text] for pristine PANi. These results demonstrate that PANi exhibits good irradiation resistance after irradiated with a dose of 100[Formula: see text]kGy. Thus, PANi could be used in high-[Formula: see text] ray (electron) environments, such as radioisotope thermoelectric generators (RTGs).

Radiation-Induced Molecular Processes in DNA: A Perspective on Gas-Phase Interaction Studies.

Studying the direct effects of DNA irradiation is essential for understanding the impact of radiation on biological systems. Gas-phase interactions are especially well suited to uncover the molecular mechanisms underlying these direct effects. Only relatively recently, isolated DNA oligonucleotides were irradiated by ionizing particles such as VUV or X-ray photons or ion beams, and ionic products were analyzed by mass spectrometry. This article provides a comprehensive review of primarily experimental investigations in this field over the past decade, emphasizing the description of processes such as ionization, fragmentation, charge and hydrogen transfer triggered by photoabsorption or ion collision, and the recent progress made thanks to specific atomic photoabsorption. Then, we outline ongoing experimental developments notably involving ion-mobility spectrometry, crossed beams or time-resolved measurements. The discussion extends to potential research directions for the future.

Nano-Titanium Oxide-Coated Carbon Nanotubes for Photothermal Therapy in the Treatment of Colorectal Cancer.

Recent studies have shown that carbon nanotubes display good potential in tumor photothermal therapy. In this study, we aimed to investigate the therapeutic potential of nano-titanium oxide-coated multi-walled carbon nanotubes (MCNTs) against colorectal cancer (CRC). Firstly, we modified TiO2 nanosheets on the surface of MCNTs to obtain nano-TiO2-coated MCNTs. Next, we conducted cell compatibility validation on nano-TiO2-coated MCNTs, and found that nano-TiO2-coated MCNTs were safe within a certain concentration range (0∼200 μg/ml). Interestingly, nano-TiO2-coated MCNTs displayed a good killing effect in CRC cells under NIR laser irradiation. Subsequently, nano-TiO2-coated MCNTs markedly promoted the proapoptotic effects of NIR laser irradiation, and significantly inhibited the expression of cell cycle proteins CCNA1 and CCND1 in CRC cells under NIR laser irradiation, which indicated that nano-TiO2-coated MCNTs exerted anti-CRC effects under NIR laser irradiation by regulating cell apoptosis and cell cycle. Furthermore, nano-TiO2-coated MCNTs accelerated inhibitory effects on the AKT signaling pathway under NIR laser irradiation. Finally, a cell line-derived xenograft model was established, and the results showed that nano-TiO2-coated MCNTs significantly exhibited superior tumor-killing ability under NIR laser irradiation in vivo. Collectively, our results demonstrate that nano-TiO2-coated MCNTs with NIR laser irradiation may serve as an effective strategy for the treatment of CRC. This article is protected by copyright. All rights reserved.

The effect of microwave irradiation on the molecular diffusion of the ethyl acetate (EA) into the blend of styrene-butadiene rubber (SBR)/ethylene-propylene-diene monomer rubber (EPDM)

The effect of microwave irradiation on the molecular diffusion of the ethyl acetate (EA) into the blend of styrene-butadiene rubber (SBR)/ethylene-propylene-diene monomer rubber (EPDM)

Effects of gamma radiation on cyclic olefin copolymers with varied norbornene content: Impacts on structure and properties at sterilization doses

Cyclic olefin copolymer (COC) is a transparent amorphous plastic known for its chemically inertness, biocompatibility, low density, and easy processability. These qualities have led to its widespread adoption in various cutting-edge applications, including the medical, packaging, optical and microelectronics. Radiation sterilization, utilizing high-energy irradiation, is a method for achieving highly effective sterilization of medical products. However, this process can induce changes in the color and properties of the COC materials. In order to comprehend the effects of ionizing radiation on COC, it is crucial to investigate the underlying reaction mechanisms. In this work, the effects of γ-ray irradiation on COC with different norbornene contents were examined. The finding revealed that tertiary alkyl radical content and the degree of oxidative degradation increased with an increase in norbornene content. Furthermore, the macroscopic properties experienced notable shifts, including decreased thermal stability, lower glass transition temperature and the change in color from colorless and transparent to yellow-green. Analysis of the melt index indicated a dominance of cross-linking phenomena with increased absorbed dose for COC with a norbornene content of 35%, while the melt flow rate steadily accelerated with the increase of absorbed dose for COC with norbornene content of 46%, 52% and 57%, leading to a predominant cracking behavior. The variation in tensile properties of the four COCs before and after irradiation were minimal, not exceeding 3%. Overall, this investigation sheds light on the intricate effects of ionizing radiation on COC and highlights the importance of understanding these mechanisms for practical applications.