Radiation Physics and Chemistry最新文献_第7页

Fukushima Daiichi Nuclear Power Plant's radioactive water: A decade of treatment and the road ahead?

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-10 DOI: 10.1016/j.radphyschem.2025.112683

Rashedul Islam Ripon , Zinnat Ara Begum , Hyoe Takata , Ismail M.M. Rahman

{"title":"Fukushima Daiichi Nuclear Power Plant's radioactive water: A decade of treatment and the road ahead?","authors":"Rashedul Islam Ripon , Zinnat Ara Begum , Hyoe Takata , Ismail M.M. Rahman","doi":"10.1016/j.radphyschem.2025.112683","DOIUrl":"10.1016/j.radphyschem.2025.112683","url":null,"abstract":"<div><div>The 2011 accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) necessitated continuous cooling water injections to stabilize the reactor's molten fuel temperature. The cooling water, along with infiltrating rainwater and groundwater, became highly contaminated with radionuclides (RNs) upon contact with the damaged reactor core. To manage this radioactive water, a multi-nuclide removal facility was constructed, designed to facilitate cooling water circulation and decontamination. The system successfully removes 62 RNs. However, despite the effectiveness of the treatment process, concerns remain regarding the planned, gradual release of the treated water into the ocean over a 30-year period. These concerns primarily stem from the presence of tritium, which is not removed during radioactive water treatment, and other RNs that are difficult to eliminate. The current review examines the complexities of water management at the FDNPP, analyzes the strategies implemented for the removal of RNs, and assesses the proposed approaches for safe discharge into the ocean.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"233 ","pages":"Article 112683"},"PeriodicalIF":2.8,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143675589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis and characterization of Dibarium Dibismuth oxide (Ba2Bi2O6) for radiation shielding application

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-10 DOI: 10.1016/j.radphyschem.2025.112660

B.M. Chandrika , L. Seenappa , Holaly Chandrashekara Shastry Manjunatha , R. Munirathnam , K.N. Sridhar , A.J. Clement Lourduraj

{"title":"Synthesis and characterization of Dibarium Dibismuth oxide (Ba2Bi2O6) for radiation shielding application","authors":"B.M. Chandrika , L. Seenappa , Holaly Chandrashekara Shastry Manjunatha , R. Munirathnam , K.N. Sridhar , A.J. Clement Lourduraj","doi":"10.1016/j.radphyschem.2025.112660","DOIUrl":"10.1016/j.radphyschem.2025.112660","url":null,"abstract":"<div><div>This study investigates Dibarium Dibismuth Oxide (Ba<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>Bi<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>6</mn></mrow></msub></math></span>) nanoparticles as a non-toxic alternative to lead for radiation shielding. Synthesized via a green method using aloe vera extract, Ba<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>Bi<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>6</mn></mrow></msub></math></span> NPs were characterized using standard techniques. PXRD confirmed a highly crystalline cubic phase with a crystallite size of 33–34 nm, while SEM revealed an agglomerated plate-like morphology FTIR confirmed Ba–O and Bi–O bonds at 695 cm<sup>−1</sup> and 351 cm<sup>−1</sup>. UV–Vis analysis showed peaks at 256 nm, 307 nm, and 399 nm, with a band gap of 3.08 eV. The shielding properties were evaluated, revealing strong gamma-ray attenuation and high neutron absorption efficiency, surpassing traditional materials like lead, concrete, and steel. Radiation shielding studies demonstrated a mass attenuation coefficient of 0.394 cm<sup>2</sup>/g at 0.276 MeV and a Tenth Value Layer (TVL) of 0.302 cm. Neutron shielding efficiency was confirmed by a scattering cross-section of 7.40 barns and an absorption cross-section of 0.034 barns. Ba<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>Bi<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>6</mn></mrow></msub></math></span> exhibits excellent shielding efficiency, making it a promising candidate for radiation shielding in medical and industrial environments, with the added benefit of reduced toxicity.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"232 ","pages":"Article 112660"},"PeriodicalIF":2.8,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Decomposition of hydrogen peroxide by gold nanoparticles leading to increase of OH radical yields: A radiosensitization potential for hadron therapy

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-10 DOI: 10.1016/j.radphyschem.2025.112687

Tamon Kusumoto , Yu Okazaki , Ryoichi Hirayama , Jun Kataoka , Stephane Roux , Michel Fromm , Rana Bazzi , Satoshi Kodaira

引用次数: 0

Effect of electron beam irradiation on microbial inactivation, nutritional and quality properties of semi-moist pet foods

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-10 DOI: 10.1016/j.radphyschem.2025.112689

Anand Kumar Sethukali , Hyun Jung Lee , Dongbin Park , Hyun Jun Kim , Hag Ju Lee , Cheorun Jo

{"title":"Effect of electron beam irradiation on microbial inactivation, nutritional and quality properties of semi-moist pet foods","authors":"Anand Kumar Sethukali , Hyun Jung Lee , Dongbin Park , Hyun Jun Kim , Hag Ju Lee , Cheorun Jo","doi":"10.1016/j.radphyschem.2025.112689","DOIUrl":"10.1016/j.radphyschem.2025.112689","url":null,"abstract":"<div><div>The objective of this study was to evaluate the effect of electron beam irradiation (E-beam) on semi-moist pet foods at different absorbed doses. The samples were exposed to e-beam at dose levels of 0, 2.5, 5, and 10 kGy. Then, their effect on microbiological, nutritional, and physicochemical properties was analyzed during 60 days of storage. A dose-dependent effect was observed in bacterial pathogens, especially, 10 kGy sterilized them without further growth throughout the storage period. The nutrient analysis confirmed that 10 kGy of e-beam irradiation did not significantly influence the nutritional components of semi-moist pet foods, ensuring they are nutritionally safe for pets. Irradiated samples showed less changes in quality over time, with lower microbial growth and stable attributes like water activity, pH, and redness (<em>a∗</em>). While samples treated with 10 kGy initially showed more lipid oxidation and protein degradation, these differences were not significant by day 60, suggesting that higher doses did not affect physicochemical properties during storage. In contrast, non-irradiated samples experienced microbial and physicochemical changes over the extended storage. Therefore, we conclude that e-beam irradiation up to 10 kGy can secure microbial safety in semi-moist pet foods, preserving their nutritional and quality attributes for pets’ consumption.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"232 ","pages":"Article 112689"},"PeriodicalIF":2.8,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low energy electron interaction and dissociative ionization of pyridazine

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-09 DOI: 10.1016/j.radphyschem.2025.112655

Yurekha S.P., Dhanoj Gupta

引用次数: 0

Uncertainty estimation of minimum detectable activity through sparse spectrum using kernel-based Gaussian process regression

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-08 DOI: 10.1016/j.radphyschem.2025.112667

Jaehyun Park , Gyohyeok Song , Wonku Kim , Shin Ki-baek , Yeon Kyoung Choi , Gyuseong Cho

{"title":"Uncertainty estimation of minimum detectable activity through sparse spectrum using kernel-based Gaussian process regression","authors":"Jaehyun Park , Gyohyeok Song , Wonku Kim , Shin Ki-baek , Yeon Kyoung Choi , Gyuseong Cho","doi":"10.1016/j.radphyschem.2025.112667","DOIUrl":"10.1016/j.radphyschem.2025.112667","url":null,"abstract":"<div><div>To address the growing challenge of managing the radioactive waste generated during the decommissioning of nuclear power plants, one area under focus has been liquid radioactive waste management. This area concerns the importance of adhering to clearance levels and regulations, where Minimum Detectable Activity (MDA) plays a crucial role in determining whether liquid radioactive waste can be safely released into the environment. In this study, we obtain the sparse spectrum to calculate the uncertainty by means of kernel-based Gaussian Process Regression (GPR). After calculating the uncertainty, we applied count correction to the sparse spectrum to match the count with the long measurement spectrum. We then corrected the sparse spectrum to match that of the measurement spectrum collected over 3000 s for comparison. The results show that as the measurement time increases, the MDA converges to the true value. By applying kernel-based GPR and correcting the sparse spectrum, the uncertainty estimation of MDA achieves significantly improved accuracy, especially when the measurement time exceeds 60 s. With a measurement time of at least 60 s, a reliable MDA estimate can be obtained, allowing for more efficient and accurate MDA assessments in practical scenarios. The significance of this study lies in the fact that it offers a faster and more efficient method for estimating MDA, which can potentially enhance the management of radioactive waste and improve the monitoring of nuclear facilities.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"233 ","pages":"Article 112667"},"PeriodicalIF":2.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Determination of Photon Therapy Beam Spectra Using Transmission and Unfolding Techniques

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-08 DOI: 10.1016/j.radphyschem.2025.112670

Milomir Milaković , Nikola Jovančević , Dimitrije Maletić , Miodrag Krmar , David Knežević , Strahinja Ilić , Žarko Medić , Jelena Bardak , Bellona Bles

{"title":"Determination of Photon Therapy Beam Spectra Using Transmission and Unfolding Techniques","authors":"Milomir Milaković , Nikola Jovančević , Dimitrije Maletić , Miodrag Krmar , David Knežević , Strahinja Ilić , Žarko Medić , Jelena Bardak , Bellona Bles","doi":"10.1016/j.radphyschem.2025.112670","DOIUrl":"10.1016/j.radphyschem.2025.112670","url":null,"abstract":"<div><div>For effective radiation therapy, it is crucial to understand the properties of the radiation being utilized. The challenge lies in the dose distribution within an irradiated inhomogeneous medium composed of various tissues, each with different attenuation characteristics. Consequently, it is essential to determine the mass energy absorption coefficient for each point within the irradiated volume and the incident beam spectrum of the therapeutic accelerator to accurately calculate the dose distribution in the treated body area. In this study, our objective was to determine the photon radiation spectrum of a medical linear accelerator using a measurement technique based on the transmission and unfolding method. The radiation spectrum of the Varian DHX therapeutic linear accelerator was analyzed using the attenuation (transmission) method. This study focused exclusively on the 6 MeV photon radiation spectrum. Radiation doses were measured after attenuation through materials such as water, aluminum, lead, iron, and copper. The photon radiation spectrum was determined using these measured data, the known attenuation coefficients for the materials, and the standard unfolding technique, which is well-established in neutron and photon activation measurements. The results of this study demonstrate that the applied technique can reliably provide information about the photon radiation spectrum characteristics of medical linear accelerators. The analysis reveals that the radiation doses calculated using the photon spectrum obtained via the unfolding method are more consistent with the measured values than those calculated using the standard Schiff spectrum.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"232 ","pages":"Article 112670"},"PeriodicalIF":2.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Structural, morphological, and radiation shielding properties of Nd2O3-Doped B2O3–SiO2–Na2CO3 glasses derived from gibbsite ore

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-07 DOI: 10.1016/j.radphyschem.2025.112676

Mohammad Marashdeh , F.H. Sallam , Hanan Akhdar , K.A. Mahmoud , Haitham Alrajhi , Mohamed Tharwat

{"title":"Structural, morphological, and radiation shielding properties of Nd2O3-Doped B2O3–SiO2–Na2CO3 glasses derived from gibbsite ore","authors":"Mohammad Marashdeh , F.H. Sallam , Hanan Akhdar , K.A. Mahmoud , Haitham Alrajhi , Mohamed Tharwat","doi":"10.1016/j.radphyschem.2025.112676","DOIUrl":"10.1016/j.radphyschem.2025.112676","url":null,"abstract":"<div><div>The neodymium oxide product was separated from Gibbsite natural ore by an ion exchange process. Nd<sub>2</sub>O<sub>3</sub> was doped in a glass system using a melt-quenching technique with the formula 55B<sub>2</sub>O<sub>3</sub>–15SiO<sub>2</sub>-(30-x)Na<sub>2</sub>CO<sub>3</sub>-xNd<sub>2</sub>O<sub>3</sub> where x varied from 0 to 0.5 mol%. The amorphous structure of the glass system is ensured using X-ray analysis and the surface morphology is described using a scanning electron microscope and infrared spectroscopy. The Monte Carlo simulation method and the theoretical calculation were applied to estimate the role of Nd<sub>2</sub>O<sub>3</sub> concentration on the radiation shielding properties of the prepared glass samples. The increase in the Nd<sub>2</sub>O<sub>3</sub> content increases the linear attenuation coefficient and radiation protection efficiency while the half-value thickness decreases. The linear attenuation coefficient increased between 0.187 and 0.191 cm<sup>−1</sup> at 0.662 MeV, while the half-value thickness decreased between 3.698 and 3.628 cm. The addition of Nd<sub>2</sub>O<sub>3</sub> enhances the radiation shielding properties of the prepared glass samples.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"232 ","pages":"Article 112676"},"PeriodicalIF":2.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dosimetric comparison of three different cardiac CT angiography techniques in a dual-source scanner using size-specific dose estimation (SSDE)

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-07 DOI: 10.1016/j.radphyschem.2025.112678

Mostafa Robatjazi , Navid Sarmast Alizadeh , Mikaeil Molazadeh , Fatemeh Shokoohy , Seyed Alireza Javadinia , Amir Dareyni , Maryam Mosavi

{"title":"Dosimetric comparison of three different cardiac CT angiography techniques in a dual-source scanner using size-specific dose estimation (SSDE)","authors":"Mostafa Robatjazi , Navid Sarmast Alizadeh , Mikaeil Molazadeh , Fatemeh Shokoohy , Seyed Alireza Javadinia , Amir Dareyni , Maryam Mosavi","doi":"10.1016/j.radphyschem.2025.112678","DOIUrl":"10.1016/j.radphyschem.2025.112678","url":null,"abstract":"<div><h3>Background</h3><div>Cardiac computed tomography angiography (CCTA) is a non-invasive imaging technique for detecting coronary artery disease. This study aimed to evaluate radiation doses in three CCTA techniques using a dual-source CT scanner, focusing on Size-Specific Dose Estimation (SSDE) and other dose indexes.</div></div><div><h3>Methods</h3><div>Ninety-three patients were categorized into three groups: FLASH technique (44 patients), retrospective electrocardiogram (ECG) triggering technique (13 patients), and prospective ECG triggering technique (36 patients). Dose-length product (DLP), Volumetric CT dose index (CTDIvol), SSDE, and effective dose were calculated and compared among the groups.</div></div><div><h3>Results</h3><div>There was a significant difference in CTDIvol and DLP values (P < 0.001) among CCTA techniques. The retrospective technique had higher geometrical SSDE (gSSDE) and water-equivalent SSDE (wSSDE) values (P < 0.001), while the FLASH technique had lower values. No significant effective dose difference existed between prospective and FLASH techniques (P = 0.17), but significant differences were observed between FLASH vs. retrospective and prospective vs. retrospective (both P < 0.001). Gender did not significantly affect dose values. Correlation analysis showed poor correlations between gSSDE, wSSDE, related effective diameters, and factors like age, kV, and mAs.</div></div><div><h3>Conclusion</h3><div>This study highlights the importance of radiation dose consideration in selecting appropriate CCTA technique based on patient factors. The results showed that FLASH has the lowest doses, and incorporating SSDE improves dose accuracy. Our findings support the adoption of SSDE to optimize imaging protocols and enhance patient safety in cardiovascular imaging.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"232 ","pages":"Article 112678"},"PeriodicalIF":2.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tungsten carbide-based shape memory biopolymer nanocomposites as a promising new gamma radiation shielding material

IF 2.8 3区物理与天体物理

Radiation Physics and Chemistry Pub Date : 2025-03-07 DOI: 10.1016/j.radphyschem.2025.112677

Mustafa Ersin Pekdemir , Demet Yılmaz , Sibel Selçuk Pekdemir , Yahya Taşgın , Busenur Ekmen

{"title":"Tungsten carbide-based shape memory biopolymer nanocomposites as a promising new gamma radiation shielding material","authors":"Mustafa Ersin Pekdemir , Demet Yılmaz , Sibel Selçuk Pekdemir , Yahya Taşgın , Busenur Ekmen","doi":"10.1016/j.radphyschem.2025.112677","DOIUrl":"10.1016/j.radphyschem.2025.112677","url":null,"abstract":"<div><div>In this study, structural, thermal and radiation shielding properties of Polylactic acid (PLA)/polyhydroxyalkanoates (PHAs)/Tungsten Carbide (WC) nanocomposite films were investigated. PHA/PLA/WC composite films were prepared by using different amounts of WC (5%, 10%, 18%, 28%). Characterization of the composite films was carried out by Attenuated Total Reflection Infrared Spectroscopy (ATR-IR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The linear and mass attenuation coefficients (LAC and MAC), mean free path (MFP), Half-Value Layer (HVL), Tenth Value Layer (TVL), effective atomic numbers (Z<sub>eff</sub>), and effective electron densities (N<sub>el</sub>) of the synthesized composite films were experimentally measured from 53.16 to 383.85 keV. Also, the neutron equivalent dose rates for the prepared film samples were determined. Exposure buildup factor (EBF) and fast neutron removal cross section (ΣR) were theoretically calculated. The particle shielding characteristics of the composite films were evaluated. The MFP values at 356.01 keV are 8.211 cm, 7.772 cm, 7.360 cm, 6.710 cm and 5.942 cm for PLA/PHA, PLA/PHA/5%WC, PLA/PHA/10%WC, PLA/PHA/18%WC and PLA/PHA/28%WC, respectively. It was observed that an increase in WC content enhances the gamma shielding abilities in PHA/PLA films. The results revealed that PHA/PLA/WC composite materials can be used as protective coating materials.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"232 ","pages":"Article 112677"},"PeriodicalIF":2.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143583093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0