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Comparisons of dosimetric properties between GD-300 series of radiophotoluminescent glass detectors and GR-200 series of thermoluminescent detectors

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Nuclear Science and Techniques 2007年第6期18卷 362-365页

作者： zhuo weihai LIU Weiqi HUANG Gang ZHU Guoying MA Guocai Institute of Radiation Medicine Fudan University Shanghai 200032 China

In order to compare the dosimetric properties of two kinds of solid state detectors used for monitoring ex- ternal exposures,experiments were performed for the GD-300 series of radiophotoluminescent glass detectors (RPLGD)and the GR-200 series of thermoluminescent detectors(TLD).X-rays and ^(137)Cs and ^(60)Coγ-rays were used to irradiate the RPLGDs and TLDs,their dose linearity,uniformity/reproducibility of signal,fading effect and energy dependence were *** kinds of the detectors have generally good dosimetric *** dose linearity and energy dependence of the GD-351 dosimeters and the TLDs are nearly the same,but the RPLGD is much better than the TLD in terms of the uniformity and fading effect.

关键词：放射光致发光热致发光衰落效应能量反应剂量计

A new sampler for simulating aerosol deposition in the respiratory tract

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Nuclear Science and Techniques 2008年第3期19卷 169-173页

作者： LI Dehong zhuo weihai YI Yanling CHEN Bo LIU Haikuan Institute of Radiation Medicine Fudan University Shanghai 200032 China

For estimation of the deposition fractions of radon progeny in different regions of the respiratory tract, a new sampler consisting of three different configurations of sampling heads was developed. The deposition fractions of aerosols on the wire screens inside the sampling heads were calculated with the fan model of filtration theory. The deposition fractions of aerosols in different regions of the respiratory tract were calculated with the lung dose evaluation program (LUDEP)developed by National Radiological Protection Board (NRPB) as references. In general indoor and mine environments, the deviation between the deposition fractions of attached aerosol on the wire screens designed in this study and its reference values in the respiratory tract is less than 5%. It is possible to accurately estimate the deposition fractions of radon progeny in different regions of the respiratory tract through mimic measurements of radon progeny collected with the new sampler.

关键词：放射性污染环境放射学气溶胶呼吸过程

A progress review on methods for in vivo measurement of ^(131)I in thyroids by using portable gamma spectrometers

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Radiation Medicine and Protection 2021年第4期2卷 155-159页

作者： Hongming Liu Bo Chen weihai zhuo Institute of Radiation Medicine Fudan UniversityShanghai 200032China

Iodine-131 is a highly toxic and volatile artificial radionuclide that is easily inhaled or ingested by the human body and selectively accumulates in thyroid *** the development of nuclear medicine and nuclear power plants,the unintended release of ^(131)I has been widely studied,and the in vivo measurement of ^(131)I in the thyroid has become a research hotspot in the field of radiation *** recent decades,several methods and devices have been developed for in vivo measurements with respect to different measurement purposes and *** this work,for more accurate determinations of individual ^(131)I in the thyroid in the field,the uncertainties of measurements by using portable gamma spectrometers were reviewed and analyzed,and monitoring strategies for improving the accuracy were proposed and prospected.

关键词： ^(131)I In vivo measurement Thyroid Portable gamma spectrometer Uncertainty

Wear-resistant Ag-MAX phase 3D interpenetrating-phase composites:Processing,structure,and properties

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Nano Research 2024年第2期17卷 806-819页

作者： Yu Guo Xi Xie Zengqian Liu Longchao zhuo Jian Zhang Shaogang Wang Qiqiang Duan Qing Jia Dake Xu weihai Xue Deli Duan Filippo Berto Zhefeng Zhang Rui Yang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Electrobiomaterials Institute Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Chemical Engineering Materials and EnvironmentSapienza University of RomeRoma 00185Italy

Electrical contact materials are generally Ag-or Cu-based composites and play a critical role in ensuring the reliability and efficiency of electrical equipments and electronic *** MAX(M is an early transition metal,A is an element from III or IV main groups,and X is carbon or/and nitrogen)phase ceramics display a unique combination of properties and may serve as an ideal reinforcement phase for electrical contact *** biological materials evolved in nature generally exhibit three-dimensional(3D)interpenetrating-phase architectures,which may offer useful inspiration for the architectural design of electrical contact ***,a series of bi-continuous Ag-Ti_(3)SiC_(2) MAX phase composites with high ceramic contents exceeding 50 vol.%and having micron-and ultrafine-scaled 3D interpenetrating-phase architectures,wherein both constituents were continuous and mutually interspersed,were exploited by pressureless infiltration of Ag melt into partially sintered Ti_(3)SiC_(2) *** mechanical and electrical properties as well as the friction and wear performance of the composites were investigated and revealed to be closely dependent on the ceramic contents and characteristic structural *** composites exhibited a good combination of properties with high hardness over 2.3 GPa,high flexural strength exceeding 530 MPa,decent fracture toughness over 10 MPa·m^(1/2),and good wear resistance with low wear rate at an order of 10^(-5)mm^(3)/(N·m),which were much superior compared to the counterparts made by powder metallurgy *** particular,the hardness,electrical conductivity,strength,and fracture toughness of the composites demonstrated a simultaneous improvement as the structure was refined from micron-to ultrafine-scales at equivalent ceramic *** good combination of properties along with the facile processing route makes the Ag-Ti_(3)SiC_(2)3D interpenetrating-phase composites appealing for electrical contact applicatio

关键词： three-dimensional(3D)interpenetrating-phase architecture Ag-MAX(M=early transition metal A=element from III or IV main groups and X=carbon or/and nitrogen)phase composites melt infiltration electrical contact materials mechanical

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氡致肺癌危险度评价模型及其应用初探

中华放射医学与防护杂志 2022年第4期42卷 315-320页

作者：强紫琪陈波卓维海复旦大学公共卫生学院上海200032 复旦大学放射医学研究所上海200032

氡是紧随吸烟之后的第二大致肺癌环境因素。近年来, 随着氡与肺癌流行病学调查研究的不断深入及其方法学的进一步完善, 相关危险度模型的研究也取得了一些新的进展。本文对迄今为止多个国际学术组织或团队给出的氡致肺癌超额相对危险度... 详细信息

氡是紧随吸烟之后的第二大致肺癌环境因素。近年来, 随着氡与肺癌流行病学调查研究的不断深入及其方法学的进一步完善, 相关危险度模型的研究也取得了一些新的进展。本文对迄今为止多个国际学术组织或团队给出的氡致肺癌超额相对危险度模型进行综述, 简要介绍所建立模型的背景及其考虑的主要因素;结合我国不同年代的室内氡浓度水平进行了氡致肺癌危险度的试算, 并为准确开展我国室内氡致肺癌风险评估研究提出了参考建议。

关键词：氡肺癌相对危险度风险模型

一种可快速估算环境放射性污染所致公众外照射剂量的新软件

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中华放射医学与防护杂志 2023年第10期43卷 805-811页

作者：汪景航陈波卓维海复旦大学放射医学研究所上海200032

目的开发便于快速估算环境放射性污染所致公众成员外照射剂量的应用软件。方法基于国际放射防护委员会(ICRP)提供的数据,创建公众(成人与不同年龄组儿童)在不同环境暴露情形下的外照射剂量率转换系数数据库;在Windows操作系统内利用Pyt... 详细信息

目的开发便于快速估算环境放射性污染所致公众成员外照射剂量的应用软件。方法基于国际放射防护委员会(ICRP)提供的数据,创建公众(成人与不同年龄组儿童)在不同环境暴露情形下的外照射剂量率转换系数数据库;在Windows操作系统内利用Python语言编写数据调用与计算程序,并借助PyQt工具包设计软件界面;为测试该软件的计算结果,试算了几种最可能出现放射性核素在3种环境暴露情景下所致公众成员的外照射剂量差异,并开展了合理性分析。结果本研究开发软件可在带Windows系统的个人电脑上快速完成放射性核素污染外照射所致公众的器官当量剂量与全身有效剂量的估算,计算结果合理。结果表明,公众成员的年龄越小,器官当量剂量和有效剂量通常越大;对于相同活度浓度且达到放射性平衡90Sr的土壤表面污染和水体污染,婴儿的有效剂量约为成人的6.08倍和2.51倍。结论本研究开发的软件具有操作简单、计算速度快等优点,适用于核事故应急等情形下快速估算公众成员外照射剂量。

关键词：放射性污染外照射当量剂量有效剂量软件工具

便携式NaI(Tl)γ谱仪对甲状腺内^(131)I的探测效率模拟计算

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中华放射医学与防护杂志 2022年第8期42卷 618-623页

作者：刘洪铭陈波卓维海复旦大学放射医学研究所上海200032

目的计算不同甲状腺-颈部刻度模体和测量位置对便携式γ谱仪的全能峰探测效率影响,为更加准确开展人体甲状腺内^(131)I活度现场测量提供指导。方法在对4种典型的甲状腺-颈部模体和用于甲状腺内^(131)I活度测量的便携式3英寸NaI(TI)γ谱... 详细信息

目的计算不同甲状腺-颈部刻度模体和测量位置对便携式γ谱仪的全能峰探测效率影响,为更加准确开展人体甲状腺内^(131)I活度现场测量提供指导。方法在对4种典型的甲状腺-颈部模体和用于甲状腺内^(131)I活度测量的便携式3英寸NaI(TI)γ谱仪进行建模的基础上,结合可能的现场测量情景,利用蒙特卡罗方法模拟计算便携式NaI(TI)γ谱仪在不同测量距离、不同甲状腺深度、不同甲状腺体积等条件下的全能峰(364.5 keV)探测效率。结果NaI(TI)γ谱仪的探测效率随探测器与颈部表面距离增加而显著递减,紧贴颈部表面的探测效率约为距颈部表面15 cm的15倍;探测效率随甲状腺深度增加而明显降低,在颈部表面测量时,深度为2 mm的探测效率约为30 mm的3.6倍;探测效率随甲状腺体积增大而减小,在颈部表面测量时,体积为1 ml的探测效率是30 ml的1.71倍;探测效率随探测器中心偏移而降低,尤其是在颈部表面测量时,中心偏离2 cm会导致探测效率下降约15%。结论利用便携式NaI(TI)γ谱仪开展人体甲状腺内^(131)I活度准确测量,不仅需要掌握探测效率刻度时的测量距离,还需了解所用刻度模体内的甲状腺深度与体积。

关键词： ^(131)I 甲状腺-颈部模体便携式γ谱仪探测效率蒙特卡罗模拟

基于EPA/BEIR-VI模型的我国居室内氡致肺癌风险估计

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中华放射医学与防护杂志 2022年第1期42卷 45-49页

作者：苗晓翔苏垠平卓维海孙全富中国疾病预防控制中心辐射防护与核安全医学所辐射防护与核应急中国疾病预防控制中心重点实验室北京100088 复旦大学放射医学研究所上海200032

目的估计我国居室内氡导致的居民肺癌归因份额。方法利用较为权威且适用的EPA/BEIR-VI风险模型, 基于我国2015年肺癌死亡率、全死因死亡率以及有代表性的吸烟率和居室内氡平均浓度, 预测我国居室内氡浓度水平致肺癌死亡风险。结果非吸... 详细信息

目的估计我国居室内氡导致的居民肺癌归因份额。方法利用较为权威且适用的EPA/BEIR-VI风险模型, 基于我国2015年肺癌死亡率、全死因死亡率以及有代表性的吸烟率和居室内氡平均浓度, 预测我国居室内氡浓度水平致肺癌死亡风险。结果非吸烟男性人群居室内氡致肺癌死亡超额相对危险(ERR)高于吸烟人群, 且达到年龄为50岁时, 不吸烟与吸烟的男性ERR值最高, 分别为0.511、0.230;假定开始暴露年龄为0岁, 相同氡浓度下, 不吸烟的男性与女性人群相对终生危险(LRR)要高于同性别吸烟人群, 且浓度越高其肺癌死亡LRR也越高。假定我国居室内氡浓度水平为30 Bq/m3, 2015年由居室内氡所致肺癌死亡人数约为55 512人, 据此估算约有6.62%的肺癌死亡是由居室内氡暴露造成的。如果假设我国居室内氡浓度水平为40 Bq/m3和70 Bq/m3, 则分别约有8.82%和15.38%的肺癌死亡可归因于居室内氡暴露。结论居室内氡是导致我国居民罹患肺癌的重要环境因素, 应采取有力措施防治我国居室内氡浓度水平升高。为能进一步准确评估我国居室内氡致肺癌死亡风险, 还需要更为全面和详细的我国居室内氡浓度水平等数据。

关键词： EPA/BEIR-VI模型居室氡氡暴露肺癌风险

Single-cell transcriptomic Atlas of aging macaque ocular outflow tissues

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Protein & Cell 2024年第8期15卷 594-611页

作者： Jian Wu Chaoye Wang Shuhui Sun Tianmin Ren Lijie Pan Hongyi Liu Simeng Hou Shen Wu Xuejing Yan Jingxue Zhang Xiaofang Zhao weihai Liu Sirui Zhu Shuwen Wei Chi Zhang Xu Jia Qi Zhang Ziyu Yu Yehong zhuo Qi Zhao Chenlong Yang Ningli Wang Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Key Laboratory of Ophthalmology and Visual SciencesBeijing 100730China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060China State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineSun Yat-sen University Cancer CenterGuangzhou 510060China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Department of Neurosurgery Peking University Third HospitalCenter for Precision Neurosurgery and Oncology of Peking University Health Science CenterBeijing 100191China Spencer Center for Vision Research Byers Eye InstituteSchool of MedicineStanford UniversityPalo AltoCA 94304USA

The progressive degradation in the trabecular meshwork(TM)is related to age-related ocular diseases like primary open-angle ***,the molecular basis and biological significance of the aging process in TM have not been fully ***,we established a dynamic single-cell transcriptomic landscape of aged macaque TM,wherein we classified the outflow tissue into 12 cell subtypes and identified mitochondrial dysfunction as a prominent feature of TM ***,we divided TM cells into 13 clusters and performed an in-depth analysis on cluster O,which had the highest aging score and the most significant changes in cell proportions between the two ***,we found that the APOE gene was an important differentially expressed gene in cluster O during the aging process,highlighting the close relationship between cell migration and extracellular matrix regulation,and TM *** work further demonstrated that silencing the APOE gene could increase migration and reduce apoptosis by releasing the inhibition on the PI3K-AKT pathway and downregulating the expression of extracellular matrix components,thereby increasing the aqueous outflow rate and maintaining intraocular pressure within the normal *** work provides valuable insights for future clinical diagnosis and treatment of glaucoma.

关键词： single-cell transcriptomic atlas macaque trabecular meshwork ocular outflow tissue aging