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Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng Wang Yi Gu mao-lin xiong Liang-Quan Ge Qing-Xian Zhang Guo-Qiang Zeng Heng Lu Sheng-Liang Guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

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用离散波数法计算层状介质中地震破裂产生的动态位移场

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云南大学学报（自然科学版） 2005年第5期27卷 410-415页

作者：解朝娣吴小平虎雄林云南大学地球物理系云南昆明650091

设震源为一个以有限速度扩展的双侧破裂走滑断层,在1°×1°的研究范围内,采用离散波数法,首先计算出144个场点处的位移时程,最后得到了地震破裂产生的动态位移场,并讨论了其动态辐射特征.地震破裂动态位移场的计算为将来实现地震动态... 详细信息

设震源为一个以有限速度扩展的双侧破裂走滑断层,在1°×1°的研究范围内,采用离散波数法,首先计算出144个场点处的位移时程,最后得到了地震破裂产生的动态位移场,并讨论了其动态辐射特征.地震破裂动态位移场的计算为将来实现地震动态应力场的计算奠定了基础.

关键词：离散波数法地震破裂动态位移场

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2003年大姚6.2、6.1级地震构造应力环境及静态应力触发研究

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地震研究 2013年第1期36卷 47-56页

作者：虎雄林解朝娣刘丽芳云南省地震局云南昆明650224 云南大学地球物理系云南昆明650091

利用2003年7月21日、10月16日大姚6.2、6.1级地震余震序列的震源机制解资料,采用滑动方向拟合法反演出大姚两次强震的构造应力,定量给出其构造应力变化量。以反演得到的2003年大姚6.2、6.1级地震构造应力为基础,分别计算两次强震后产生... 详细信息

利用2003年7月21日、10月16日大姚6.2、6.1级地震余震序列的震源机制解资料,采用滑动方向拟合法反演出大姚两次强震的构造应力,定量给出其构造应力变化量。以反演得到的2003年大姚6.2、6.1级地震构造应力为基础,分别计算两次强震后产生的静态库仑破裂应力变化,研究大姚6.2级地震引起的应力变化是否触发了6.1级地震。结果显示:两次地震发生后震源区构造应力场最大主压应力S1作用由北东向近水平作用为主转为北东东向水平作用,6.2级地震对6.1级地震有明显的触发作用。

关键词：大姚地震震源机制解构造应力场库仑破裂应力滑动方向拟合

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Solar flare forecasting based on a Fusion Model

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Earth and Planetary Physics 2025年第1期9卷 171-181页

作者： YiYang Li ShiYong Huang SiBo Xu ZhiGang Yuan Kui Jiang QiYang xiong RenTong lin School of Earth and Space Science Technology Hubei Luojia LaboratoryWuhan UniversityWuhan 430072China

Solar flare prediction is an important subject in the field of space *** learning technology has greatly promoted the development of this *** this study,we propose a novel solar flare forecasting model integrating Deep Residual Network(ResNet)and Support Vector Machine(SVM)for both≥C-class(C,M,and X classes)and≥M-class(M and X classes)*** collected samples of magnetograms from May 1,2010 to September 13,2018 from Space-weather Helioseismic and Magnetic Imager(HMI)Active Region Patches and then used a cross-validation method to obtain seven independent data *** then utilized five metrics to evaluate our fusion model,based on intermediate-output extracted by ResNet and SVM using the Gaussian kernel *** results show that the primary metric true skill statistics(TSS)achieves a value of 0.708±0.027 for≥C-class prediction,and of 0.758±0.042 for≥M-class prediction;these values indicate that our approach performs significantly better than those of previous *** metrics of our fusion model’s performance on the seven datasets indicate that the model is quite stable and robust,suggesting that fusion models that integrate an excellent baseline network with SVM can achieve improved performance in solar flare ***,we also discuss the performance impact of architectural innovation in our fusion model.

关键词： solar flare pace weather deep learning Fusion Model

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The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong Zhang Zhiying Chen Yinyi xiong Qin Zhou ling-Qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

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光合作用系统模型与作物高光效改良

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生命科学 2024年第9期36卷 1123-1140页

作者：刘扶桑宋青峰于桂朝毛林雄朱新广中国科学院分子植物科学卓越创新中心植物分子遗传国家重点实验室上海200032 荷兰瓦赫宁根大学植物科学系作物系统分析中心瓦赫宁根4306700 AK

提高光合效率是提高作物产量的有效手段。然而光合系统的复杂性使得单纯利用遗传手段鉴定提高光合效率的有效靶点无论从时间上还是从经济上成本都极高。构建并利用多尺度光合系统成为当前鉴定控制光合效率核心靶点的重要手段。本文回顾... 详细信息

提高光合效率是提高作物产量的有效手段。然而光合系统的复杂性使得单纯利用遗传手段鉴定提高光合效率的有效靶点无论从时间上还是从经济上成本都极高。构建并利用多尺度光合系统成为当前鉴定控制光合效率核心靶点的重要手段。本文回顾了近年来光合系统模型的主要研究进展和主要应用实例,并进一步探讨了提高作物产量的光合作用系统模型未来的发展和应用方案。

关键词：光合作用光能利用效率系统模型数字植物产量

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Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei xiong Xuan Ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

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Vertical gradients of neutral winds observed by ICON and estimated by the Horizontal Wind Model during the geomagnetic storm on August 26−28,2021

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Earth and Planetary Physics 2025年第1期9卷 69-80页

作者： JiaWei Wu Chao xiong YuYang Huang YunLiang Zhou Department of Space Physics School of Electronic InformationHubei Luojia LaboratoryWuhan UniversityWuhan 430072China

The Michelson Interferometer for Global High-resolution Thermospheric Imaging(MIGHTI)onboard the Ionospheric Connection Explorer(ICON)satellite offers the opportunity to investigate the altitude profile of thermospheric *** this study,we used the red-line measurements of MIGHTI to compare with the results estimated by Horizontal Wind Model 14(HWM14).The data selected included both the geomagnetic quiet period(December 2019 to August 2022)and the geomagnetic storm on August 26-28,*** the geomagnetic quiet period,the estimations of neutral winds from HWM14 showed relatively good agreement with the observations from *** to the ICON observations,near the equator,zonal winds reverse from westward to eastward at around 06:00 local time(LT)at higher altitudes,and the stronger westward winds appear at later LTs at lower *** around 16:00 LT,eastward winds at 300 km reverse to westward,and vertical gradients of zonal winds similar to those at sunrise hours can be *** the middle latitudes,zonal winds reverse about 2-4 h *** winds vary more significantly than zonal winds with seasonal and latitudinal *** to the ICON observations,in the northern low latitudes,vertical reversals of meridional winds are found at 08:00-13:00 LT from 300 to 160 km and at around 18:00 LT from 300 to 200 km during the June *** reversals of meridional winds are found at 04:00-07:00 LT from 300 to 160 km and at 22:00-02:00 LT from 270 to 200 km during the December *** the southern low latitudes,meridional wind reversals occur at 08:00-11:00 LT from 200 to 160 km and at 21:00-02:00 LT from 300 to 200 km during the June *** the December solstice,reversals of the meridional wind appear at 20:00-01:00 LT below 200 km and at 06:00-11:00 LT from 300 to 160 *** the northern middle latitudes,the northward winds are dominant at 08:00-14:00 LT at 230 km during the June *** winds persist until

关键词： horizontal neutral winds vertical gradients Ionospheric Connection Explorer satellite Horizontal Wind Model 14 geomagnetic storm

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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

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阿克拉霉素影响骨髓增生异常综合征细胞株细胞增殖及其机制的初步研究

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实用肿瘤杂志 2002年第2期17卷 88-92页

作者：林茂芳熊红蔡真佟红艳钱文斌蒋燕灵浙江大学医学院附属第一医院血液科浙江杭州310003

目的　探讨阿克拉霉素 ( aclacinomycin,ACM)对骨髓增生异常综合征 ( myelodysplastic syndrome,MDS)细胞株 ( MUTZ- 1)细胞的体外作用及其机制 ,以期为进展期 MDS的治疗提供理论基础。方法　采用 MTT比色法、流式细胞术、DNA凝胶电泳... 详细信息

目的　探讨阿克拉霉素 ( aclacinomycin,ACM)对骨髓增生异常综合征 ( myelodysplastic syndrome,MDS)细胞株 ( MUTZ- 1)细胞的体外作用及其机制 ,以期为进展期 MDS的治疗提供理论基础。方法　采用 MTT比色法、流式细胞术、DNA凝胶电泳法研究 ACM对 MU TZ- 1细胞生长的影响。结果　 ( 1) ACM对 MUTZ- 1细胞的生长具有抑制作用 ,其 4 8小时 IC50 为 0 .4 6μmol。( 2 ) ACM对 MUTZ- 1细胞的作用主要为诱导凋亡。( 3 ) ACM诱导 MUTZ- 1细胞凋亡 ,阻滞细胞于细胞周期的 G2 / M期。结论　 ACM可诱导 MDS细胞株细胞凋亡 ,作用靶点位于 G2 / M期。提示诱导细胞凋亡疗法治疗进展期

关键词：阿柔比星骨髓增生异常综合征投药剂量影响阿克拉霉素细胞增殖

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