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Characteristics of fine dust pollution PM₂.₅ in Hanoi in 2021 2021 年河内微尘污染 PM₂.₅ 的特征
Pub Date : 2024-06-03 DOI: 10.53747/nst.v13i4.450
Thu Bac Vuong, Lan Anh Ha, Dinh Kien Mai, Huyen Trang Nguyen
Fine particulate matter (PM2.5) is one of the most dangerous pollutions in the atmosphere in the Hanoi capital. PM2.5 fine dust pollution characteristics in Hanoi in the duration from 5/2021 to 3/2022 have been studied. The concentration of main chemical elements (such as As, Br, Ca, Cd, Ce, Cl, Cu, Fe, K, Mn, Pb, S, Sr, Ti, Zn, Zr…), main water-soluble ions (such as Na+, NH4+, K+, Mg2+, Ca2+, SO42-, Cl-, NO3-, F-, NO2-) and black carbon (BC) in the PM2.5 sample have been analyzed. The average PM2.5 fine dust concentration was (78.09 ± 51.71) µg/m3 and ranged from 17.55 to 271.39 µg/m3. PM2.5 tends to increase and is about 3.12 times larger than Who Air Quality Guidelines 2005 (25 µg/m3 for PM2.5 24h). The average PM2.5 concentration in the rainy season from 5/2021 to 9/2021 was (51.97 ± 16.40) µg/m3. This value for the dry season from 10/2021 to 3/2022 was (104.70 ± 61.19) µg/m3. It is much higher than that in the rainy season about 2.01 times. The major contributors were the secondary components such as NH4+, SO42-, NO3- and BC... The main pollution contribution sources and the potential pollution areas map have been identified. This research shows a worrying picture of fine dust PM2.5 in Hanoi in the studying duration.
细颗粒物(PM2.5)是河内首都大气中最危险的污染之一。我们对 2021 年 5 月至 2022 年 3 月期间河内的 PM2.5 微尘污染特征进行了研究。分析了 PM2.5 样品中主要化学元素(如 As、Br、Ca、Cd、Ce、Cl、Cu、Fe、K、Mn、Pb、S、Sr、Ti、Zn、Zr......)、主要水溶性离子(如 Na+、NH4+、K+、Mg2+、Ca2+、SO42-、Cl-、NO3-、F-、NO2-)和黑碳(BC)的浓度。PM2.5 微尘的平均浓度为(78.09 ± 51.71)微克/立方米,范围在 17.55 至 271.39 微克/立方米之间。PM2.5 有增加的趋势,是《2005 年空气质量指南》(PM2.5 24 小时浓度为 25 微克/立方米)的 3.12 倍。2021 年 5 月至 9 月雨季的 PM2.5 平均浓度为(51.97 ± 16.40)微克/立方米。2021 年 10 月至 2022 年 3 月旱季的这一数值为(104.70 ± 61.19)微克/立方米。比雨季的数值高出约 2.01 倍。主要污染源是 NH4+、SO42-、NO3- 和 BC 等二次成分。主要污染贡献源和潜在污染区域图已经确定。这项研究表明,研究期间河内的微尘 PM2.5 状况令人担忧。
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引用次数: 0
Effects of chemical pre-treatment methods combined with electron beam irradiation on the quality of “Edor” longan 化学预处理方法与电子束辐照相结合对 "Edor "龙眼质量的影响
Pub Date : 2024-06-03 DOI: 10.53747/nst.v13i4.409
Khanh Chu, T. Nguyen, V. Cao, Thi Thu Hong Pham, Binh Doan, Hoa Truc Tran, Tran Diem Ha Nguyen
Using electron beam (EB) radiation as a quarantine treatment when exporting fresh fruit is a development trend in the world. In this study, the effect of EB irradiation treatment in the quarantine dose (400 to 1000 Gy) on the quality of export "Edor" longan was investigated. Investigation of chemical pre - treatments measure combined with EB irradiation to decrease pericarp browning of longan has also been carried out. “Edor” longan were treated by SO2 fumigation or dipping in 1,5 N HCl solution for 20 min after EB irradiation at low quarantine dose (400 Gy). Untreated and non-irradiated fruits were used as control. That all were then stored assumed commercial conditions (25-26°C). The results showed that the treated samples delayed a decrease in the total phenolic content and had lower pericarp browning than control. In addition, the treated samples were no significantly difference in terms of weight loss, TSS, total acid content, vitamin C, ... compared with the control. In particular, the treated samples had delayed the degree of damage level due to rotting when extending shelf life up to 22 days compared the control (12 days). Therefore, the method of combining SO2 fumigation treatment with EB irradiation (400 Gy) can be used for quarantine treatment of export "Edor" longan; and treatment with 1,5 N HCl solution can be considered to replace the traditional SO2 fumigation method.
在出口新鲜水果时使用电子束(EB)辐照作为检疫处理是世界的发展趋势。本研究调查了检疫剂量(400 至 1000 Gy)的电子束辐照处理对出口 "Edor "龙眼质量的影响。此外,还研究了化学预处理措施与 EB 照射相结合,以减少龙眼果皮褐变的情况。在低检疫剂量(400 Gy)的 EB 照射后,用二氧化硫熏蒸或在 1.5 N HCl 溶液中浸泡 20 分钟对 "Edor "龙眼进行处理。未经处理和未经辐照的果实作为对照。所有样品均在商业条件下储存(25-26°C)。结果表明,与对照组相比,处理过的样品总酚含量延迟下降,果皮褐变程度较低。此外,与对照组相比,处理过的样品在重量损失、总悬浮固体、总酸含量、维生素 C 等方面没有明显差异。特别是,与对照组(12 天)相比,处理过的样品在延长货架期至 22 天时,因腐烂而造成的损坏程度有所延迟。因此,二氧化硫熏蒸处理与 EB 照射(400 Gy)相结合的方法可用于出口 "Edor "龙眼的检疫处理;用 1.5 N HCl 溶液处理可考虑取代传统的二氧化硫熏蒸方法。
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引用次数: 0
The characteristics of the vertical distribution of radionuclide in free troposphere from simplified release scenarios: a case study 从简化释放情景看自由对流层中放射性核素的垂直分布特征:案例研究
Pub Date : 2024-05-04 DOI: 10.53747/nst.v13i3.436
Xiangming Sun, K. Chung, Qiudan Dai
Dose estimation in the upper air is not studied as much as on ground level or in boundary layer. However, there is a need from stakeholders in aviation industry for a reasonable estimation of the radioactive plume impact at cruising levels. This study aims to provide a quantitative estimation of the dose and how reliable it is for dispersion processes up to seven days. A Lagrangian atmospheric dispersion model is used to estimate quantitively the vertical extension of radionuclides from simplified hypothetical radionuclide release scenarios. Sources at different latitudes are selected for simulation in a boreal winter case. Three meteorological data are examined to test the sensitivity of vertical plume distribution to driving meteorological data. The vertical distribution of air concentration of radionuclides is investigated and the associated uncertainties are analysed. It is found that the vertical extension of plumes is sensitive to meteorological data being used where vertical turbulent velocities play an important role. It is therefore necessary to address the uncertainties of air concentration or dose in the free troposphere and caution must be taken when providing the results to stakeholders.
对高空辐射剂量估算的研究不如对地面或边界层的研究多。然而,航空业的利益相关者需要对巡航水平的放射性烟羽影响进行合理估算。本研究旨在提供剂量的定量估算,以及估算在七天以内的扩散过程中的可靠性。利用拉格朗日大气弥散模型,对简化假设的放射性核素释放情况下放射性核素的垂直延伸进行定量估算。在北方冬季的情况下,选择不同纬度的辐射源进行模拟。研究了三种气象数据,以测试垂直羽流分布对驱动气象数据的敏感性。研究了空气中放射性核素浓度的垂直分布,并分析了相关的不确定性。结果发现,在垂直湍流速度起重要作用的地方,羽流的垂直延伸对所使用的气象数据很敏感。因此,有必要解决自由对流层中空气浓度或剂量的不确定性问题,在向利益相关者提供结果时必须谨慎。
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引用次数: 0
Cross-section induced uncertainties in neutron source mission rate calculations 中子源任务率计算中截面引起的不确定性
Pub Date : 2024-05-04 DOI: 10.53747/nst.v13i3.426
J. Lűley, B. Vrban, Š. Čerba, Vendula Filová, V. Necas, Matej Krivošík, P. Blahušiak, A. Javorník, J. Slučiak
Analysis presented in the paper is focused on the characterization of uncertainties induced by cross-section data, which contributing to the overall uncertainty of the correction factors. Advances in computational methods and computational power shifted the calculation of correction factors among the standard steps of the manganese bath method what decrease an interest about this part of the method. Anyway, with the development of computational tools, the cross-section data were also improved, and new evaluations of nuclear data libraries include more information about the cross-section data covariances. Therefore, the propagation of uncertainties induced by neutron cross-sections can be carried out within standard transport calculation of the manganese sulphate bath model. In this paper, the super-sequence SAMPLER module that implements stochastic techniques is used to assess the uncertainty in computed results. Reaction rates on all nuclides of the solution are computed in 400 cases with uncertain parameters and the results are evaluated by an auxiliary tool. Consideration of nuclear data uncertainty in calculations is a general trend that requires the attention of nuclear researchers and should draw attention in metrology. Additional 1.5 % (one-sigma) uncertainty is introduced to the overall uncertainty through correction factor.
本文的分析重点是横截面数据引起的不确定性的特征,这些不确定性导致了校正因子的整体不确定性。计算方法和计算能力的进步使修正系数的计算成为锰浴法的标准步骤之一,从而降低了人们对这部分方法的兴趣。无论如何,随着计算工具的发展,横截面数据也得到了改进,新的核资料库评估包含了更多关于横截面数据协方差的信息。因此,中子截面引起的不确定性的传播可以在硫酸锰浴模型的标准输运计算中进行。本文利用实施随机技术的超序列 SAMPLER 模块来评估计算结果的不确定性。在 400 个参数不确定的情况下计算了溶液中所有核素的反应速率,并通过辅助工具对结果进行了评估。在计算中考虑核数据的不确定性是大势所趋,需要核研究人员的关注,也应引起计量学界的重视。通过校正因子,在总体不确定性中引入了额外的 1.5%(一个西格玛)不确定性。
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引用次数: 0
An approach to assess the consequence of a hypothetical radionuclide release in Singapore - a densely populated urban setting 在新加坡这个人口稠密的城市环境中评估假设放射性核素释放后果的方法
Pub Date : 2024-05-04 DOI: 10.53747/nst.v13i3.431
Siao Yang Chai, Xiangming Sun
This study is to demonstrate an approach to investigate the consequence of a hypothetical radionuclide release scenario in Singapore, a typical urban setting with high population density. To this end, we made use of MACCS 4.1, a Gaussian-based atmospheric dispersion model to compute the peak dose and the population health effects. We developed the meteorological and site files from data provided by local government agencies. Our investigation showed that the chosen scenario poses very little to negligible risk to the health of local population as the peak dose received across the country is below the radiation safety level recommended by ICRP.
新加坡是一个典型的高人口密度城市,本研究旨在展示一种调查假定放射性核素释放情景后果的方法。为此,我们使用了基于高斯的大气扩散模型 MACCS 4.1 来计算峰值剂量和人口健康影响。我们根据当地政府机构提供的数据开发了气象和场地文件。调查结果表明,所选方案对当地居民健康造成的风险很小,甚至可以忽略不计,因为全国范围内的峰值剂量低于国际辐射防护委员会建议的辐射安全水平。
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引用次数: 0
Use of di-(2-ethylhexyl)-orthophosphoric acid for the extraction of lanthanum, neodymium, samarium and yttrium from nitric acid solutions 用二(2-乙基己基)正磷酸从硝酸溶液中萃取镧、钕、钐和钇
Pub Date : 2024-05-04 DOI: 10.53747/nst.v13i3.444
Vladimir Alexandrovich Karelin, Bach Thuan Kieu, Hai Son Le, N. V. Karelina
The process of separating rare-earth elements into individual components is considered the most important problem in rare-earth technology because of the similarity in their physical and chemical properties. Currently in the world dialkyl phosphate compounds are widely used as effective extractors for rare earths. However, most extraction processes have been studied from hydrochloric acid or perchlorate solutions. In Russia, tributyl phosphate has long been used to extract rare earths from nitric acid solutions, but the distribution coefficients of the elements are not high, and the process must be repeated multiple times. In this study di-(2-ethylhexyl)-orthophosphoric acid was used for the extraction of lanthanum, neodymium, samarium, and yttrium from nitric acid solutions. When the concentration of nitric acid increased, distribution coefficient of elements gradually decreased to minimum (in the range of 1 to 5M) then increased backward. However, when the concentration was too high (C > 5M), nitric acid was extracted to the organic phase due to the properties of the phosphoryl group. Moreover, the study of dependence of solvation number of neodymium on the concentrations of nitric acid shows that rare earths in the organic phase can be extracted as Re(HA2)3 (C < 1M) or Re(NO3)3«3HA (C > 5M).
由于稀土元素的物理和化学性质相似,将其分离成单个成分的过程被认为是稀土技术中最重要的问题。目前,世界上广泛使用磷酸二烷基化合物作为稀土的有效萃取剂。然而,大多数萃取工艺都是从盐酸或高氯酸盐溶液中进行研究的。在俄罗斯,长期以来一直使用磷酸三丁酯从硝酸溶液中萃取稀土,但元素的分布系数不高,而且必须多次重复萃取过程。本研究使用二(2-乙基己基)磷酸正丁酯从硝酸溶液中萃取镧、钕、钐和钇。当硝酸浓度增加时,元素的分布系数逐渐下降到最小值(在 1 至 5M 的范围内),然后回升。然而,当浓度过高时(C > 5M),由于磷基的特性,硝酸会被萃取到有机相中。此外,钕的溶解度与硝酸浓度的关系研究表明,有机相中的稀土可以以 Re(HA2)3 (C < 1M)或 Re(NO3)3"3HA (C > 5M)的形式被提取出来。
{"title":"Use of di-(2-ethylhexyl)-orthophosphoric acid for the extraction of lanthanum, neodymium, samarium and yttrium from nitric acid solutions","authors":"Vladimir Alexandrovich Karelin, Bach Thuan Kieu, Hai Son Le, N. V. Karelina","doi":"10.53747/nst.v13i3.444","DOIUrl":"https://doi.org/10.53747/nst.v13i3.444","url":null,"abstract":"The process of separating rare-earth elements into individual components is considered the most important problem in rare-earth technology because of the similarity in their physical and chemical properties. Currently in the world dialkyl phosphate compounds are widely used as effective extractors for rare earths. However, most extraction processes have been studied from hydrochloric acid or perchlorate solutions. In Russia, tributyl phosphate has long been used to extract rare earths from nitric acid solutions, but the distribution coefficients of the elements are not high, and the process must be repeated multiple times. In this study di-(2-ethylhexyl)-orthophosphoric acid was used for the extraction of lanthanum, neodymium, samarium, and yttrium from nitric acid solutions. When the concentration of nitric acid increased, distribution coefficient of elements gradually decreased to minimum (in the range of 1 to 5M) then increased backward. However, when the concentration was too high (C > 5M), nitric acid was extracted to the organic phase due to the properties of the phosphoryl group. Moreover, the study of dependence of solvation number of neodymium on the concentrations of nitric acid shows that rare earths in the organic phase can be extracted as Re(HA2)3 (C < 1M) or Re(NO3)3«3HA (C > 5M).","PeriodicalId":19445,"journal":{"name":"Nuclear Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141014398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Simulation of gamma spectra from soil samples by using MCNP: A case study 利用 MCNP 模拟土壤样本的伽马能谱:案例研究
Pub Date : 2024-05-04 DOI: 10.53747/nst.v13i3.416
An Trung Nguyen, Hao Quang Nguyen, Thi Thu Ha Nguyen, D. Duong
A comparison between the MCNP simulated gamma spectrums based on the nuclear data from NuDat with the current version 3.0 and Nucléide-Lara against measured spectra based on the IAEA reference samples has been performed to assess the influence of nuclear data of photon decay processes and cross-section of photon interactions on the quality of the simulated spectra. As the results, the appearance of some abnormal energy peaks; namely 215 keV, 571 keV, 675 keV, 1227 keV of the NuDat-based simulated spectra and 90 keV, 94 keV, 106 keV, 416 keV of the Nucléide-Lara-based simulated spectra, which were present in neither the measured spectrum nor remaining simulated spectra, indicating issues with accuracy and completeness of these dataset. In addition, the good correlation between the combined dataset-based simulated spectra and reference samples-based measured spectra within the range of 50 keV to 2620 keV suggests that this MCNP simulation configuration can be used to generate a large simulated dataset for Machine Learning (ML) models that automatically identify and qualify radioactive isotope from gamma-ray spectra, overcoming the practical limitation of number of reference samples to sufficiently generate data for training and testing ML algorithms in the field of environmental radiation [1].
輻射㈼測㈾料的伽馬能譜模擬結果與根據國際原子能機 構參考㈾料所測得的伽馬能譜結果進行比較,以評估光子衰變過 程的核資料和光子相互作用的截面對模擬能譜質素的影響。结果显示,出现了一些异常能量峰,即基于 NuDat 的模拟光谱中的 215 keV、571 keV、675 keV 和 1227 keV 以及基于 Nucléide-Lara 的模拟光谱中的 90 keV、94 keV、106 keV 和 416 keV。此外,在 50 keV 至 2620 keV 范围内,基于综合数据集的模拟光谱与基于参考样品的实测光谱之间具有良好的相关性,这表明 MCNP 模拟配置可用于生成大型模拟数据集,供机器学习(ML)模型从伽马射线光谱中自动识别和鉴定放射性同位素,从而克服参考样品数量的实际限制,为环境辐射领域训练和测试 ML 算法生成足够的数据[1]。
{"title":"Simulation of gamma spectra from soil samples by using MCNP: A case study","authors":"An Trung Nguyen, Hao Quang Nguyen, Thi Thu Ha Nguyen, D. Duong","doi":"10.53747/nst.v13i3.416","DOIUrl":"https://doi.org/10.53747/nst.v13i3.416","url":null,"abstract":"A comparison between the MCNP simulated gamma spectrums based on the nuclear data from NuDat with the current version 3.0 and Nucléide-Lara against measured spectra based on the IAEA reference samples has been performed to assess the influence of nuclear data of photon decay processes and cross-section of photon interactions on the quality of the simulated spectra. As the results, the appearance of some abnormal energy peaks; namely 215 keV, 571 keV, 675 keV, 1227 keV of the NuDat-based simulated spectra and 90 keV, 94 keV, 106 keV, 416 keV of the Nucléide-Lara-based simulated spectra, which were present in neither the measured spectrum nor remaining simulated spectra, indicating issues with accuracy and completeness of these dataset. In addition, the good correlation between the combined dataset-based simulated spectra and reference samples-based measured spectra within the range of 50 keV to 2620 keV suggests that this MCNP simulation configuration can be used to generate a large simulated dataset for Machine Learning (ML) models that automatically identify and qualify radioactive isotope from gamma-ray spectra, overcoming the practical limitation of number of reference samples to sufficiently generate data for training and testing ML algorithms in the field of environmental radiation [1].","PeriodicalId":19445,"journal":{"name":"Nuclear Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141012908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Assessing effective half-life of I-131 in 39 thyroid cancer patients at Dong Nai General Hospital 评估东奈综合医院 39 名甲状腺癌患者体内 I-131 的有效半衰期
Pub Date : 2024-05-04 DOI: 10.53747/nst.v13i3.427
Tan Duoc Nguyen, Ha Phuong Do, Pham Ngoc Trinh Tran
Radioiodine therapy to kill the residual cells after surgery in thyroid cancer patients is a widespread treatment method nowadays. Despite the therapeutic benefits, the amount of I-131 that remains in the patient's body also causes radiation risks to caregivers and persons in close contact. This study assesses the effective half-life () of I-131 in 39 patients underwent thyroid cancer treatment at Dong Nai General Hospital. Radioactive activity on the patient's body was measured by survey meter GAL20-C (ELSE SOLUTIONS), placed 1.0 meters away from the patient, at 0.5; 2.0; 4.0; 6.0; 24.0 hours; and 7 days after administration. The measurement data was fitted by a mono-exponential function respecting time by the least squares method to figure out the effective half-life. The result function has a good coefficient of determination, R2 ~ 1, Te was 7.89 +- 1.55 h (high-activity group), and 5.83+-1.76 h  (low-activity group). The effective half-life was proved to be different between these two groups of patients.
通过放射性碘治疗杀死甲状腺癌患者术后残留的细胞是目前广泛采用的治疗方法。尽管治疗效果显著,但残留在患者体内的 I-131 也会对护理人员和密切接触者造成辐射风险。本研究评估了在东奈综合医院接受甲状腺癌治疗的 39 名患者体内 I-131 的有效半衰期()。在用药后 0.5、2.0、4.0、6.0、24.0 小时和 7 天,使用离患者 1.0 米远的 GAL20-C 测量仪(ELSE SOLUTIONS)测量患者体内的放射性活度。用最小二乘法将测量数据与时间相关的单指数函数进行拟合,以计算出有效半衰期。结果函数具有良好的判定系数 R2 ~ 1,Te 为 7.89 +- 1.55 小时(高活性组)和 5.83+-1.76 小时(低活性组)。事实证明,这两组患者的有效半衰期是不同的。
{"title":"Assessing effective half-life of I-131 in 39 thyroid cancer patients at Dong Nai General Hospital","authors":"Tan Duoc Nguyen, Ha Phuong Do, Pham Ngoc Trinh Tran","doi":"10.53747/nst.v13i3.427","DOIUrl":"https://doi.org/10.53747/nst.v13i3.427","url":null,"abstract":"Radioiodine therapy to kill the residual cells after surgery in thyroid cancer patients is a widespread treatment method nowadays. Despite the therapeutic benefits, the amount of I-131 that remains in the patient's body also causes radiation risks to caregivers and persons in close contact. This study assesses the effective half-life () of I-131 in 39 patients underwent thyroid cancer treatment at Dong Nai General Hospital. Radioactive activity on the patient's body was measured by survey meter GAL20-C (ELSE SOLUTIONS), placed 1.0 meters away from the patient, at 0.5; 2.0; 4.0; 6.0; 24.0 hours; and 7 days after administration. The measurement data was fitted by a mono-exponential function respecting time by the least squares method to figure out the effective half-life. The result function has a good coefficient of determination, R2 ~ 1, Te was 7.89 +- 1.55 h (high-activity group), and 5.83+-1.76 h  (low-activity group). The effective half-life was proved to be different between these two groups of patients.","PeriodicalId":19445,"journal":{"name":"Nuclear Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141013416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Nuclide identification algorithm for Polyvinyl Toluene scintillation detector based on Deep Neural Network 基于深度神经网络的聚乙烯醇闪烁探测器核素识别算法
Pub Date : 2024-02-20 DOI: 10.53747/nst.v12i4.347
Hiep Cao, Tien Hung Dinh, Kim Chien Dinh, Thi Thoa Nguyen, D. Pham, X. H. Nguyen
Radiation portal monitors (RPMs) are now stationed at strategic areas (airports, ports, etc.) to identify the illegal transportation of radioactive sources and nuclear items. RPMs are typically fitted with a PVT detector with a high recording efficiency. Radioisotope identification from the gamma spectrum acquired on this detector is normally not regarded due to the low resolution. This research describes an artificial neural network-based isotope identification algorithm that was applied to the gamma spectrum collected from the RPM's PVT detector. With excellent precision, this approach can detect one or a mixture of isotopes on the spectrum. The model still recognizes the training isotopes with >89 percent accuracy for spectra with the gain displacement in the range of 20 percent.
现在,辐射门户监测器(RPMs)驻扎在战略要地(机场、港口等),以识别放射源和核物品的非法运输。RPM 通常装有一个记录效率很高的 PVT 探测器。由于分辨率较低,通常无法从该探测器获得的伽马能谱中识别放射性同位素。本研究介绍了一种基于人工神经网络的同位素识别算法,该算法应用于从 RPM 的 PVT 探测器采集的伽马能谱。这种方法具有极高的精确度,可以检测到光谱上的一种或多种同位素。对于增益位移在 20% 范围内的光谱,该模型识别训练同位素的准确率仍大于 89%。
{"title":"Nuclide identification algorithm for Polyvinyl Toluene scintillation detector based on Deep Neural Network","authors":"Hiep Cao, Tien Hung Dinh, Kim Chien Dinh, Thi Thoa Nguyen, D. Pham, X. H. Nguyen","doi":"10.53747/nst.v12i4.347","DOIUrl":"https://doi.org/10.53747/nst.v12i4.347","url":null,"abstract":"Radiation portal monitors (RPMs) are now stationed at strategic areas (airports, ports, etc.) to identify the illegal transportation of radioactive sources and nuclear items. RPMs are typically fitted with a PVT detector with a high recording efficiency. Radioisotope identification from the gamma spectrum acquired on this detector is normally not regarded due to the low resolution. This research describes an artificial neural network-based isotope identification algorithm that was applied to the gamma spectrum collected from the RPM's PVT detector. With excellent precision, this approach can detect one or a mixture of isotopes on the spectrum. The model still recognizes the training isotopes with >89 percent accuracy for spectra with the gain displacement in the range of 20 percent.","PeriodicalId":19445,"journal":{"name":"Nuclear Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140445982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Thermal Simulation of Burned Nuclear Fuel Elements 燃烧核燃料元件的热模拟
Pub Date : 2024-02-20 DOI: 10.53747/nst.v13i1.404
Tuan Anh Nguyen
An adjustable description of the temperature distribution in the nuclear fuel elements is evaluated to the prediction of the lifetime behavior of these components. The impact of the fuel and coolant temperature on the neutron reaction rates provides an incentive for accurate modelling of the temperature behavior under transient as well as steady-state operating conditions. This paper is to focus on the steady-state temperature field in the fuel elements. Many of the principles applied are also useful for describing the temperature field in the structure component.
对核燃料元件中温度分布的可调整描述进行了评估,以预测这些元件的寿命行为。燃料和冷却剂温度对中子反应速率的影响促使我们对瞬态和稳态运行条件下的温度行为进行精确建模。本文将重点讨论燃料元件的稳态温度场。所应用的许多原理也可用于描述结构部件中的温度场。
{"title":"Thermal Simulation of Burned Nuclear Fuel Elements","authors":"Tuan Anh Nguyen","doi":"10.53747/nst.v13i1.404","DOIUrl":"https://doi.org/10.53747/nst.v13i1.404","url":null,"abstract":"An adjustable description of the temperature distribution in the nuclear fuel elements is evaluated to the prediction of the lifetime behavior of these components. The impact of the fuel and coolant temperature on the neutron reaction rates provides an incentive for accurate modelling of the temperature behavior under transient as well as steady-state operating conditions. This paper is to focus on the steady-state temperature field in the fuel elements. Many of the principles applied are also useful for describing the temperature field in the structure component.","PeriodicalId":19445,"journal":{"name":"Nuclear Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140447227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Nuclear Science and Technology
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