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High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： shang-yu si Zhong-Liang Li Wen-Hong Jia Lian Xue Hong-Xin Luo Jian-Cai Xu Bai-Fei Shen Lin-Gang Zhang Liang-Liang Ji yu-Xin Leng Ren-Zhong Tai shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the shanghai Synchrotron Radiation Facility using a si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was *** result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet ***,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

Development of aperiodic multilayer mirrors operated at W-Lβline for plasma diagnostics application

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Nuclear Science and Techniques 2023年第11期34卷 77-84页

作者： Ze‑Hua Yang Jing‑Tao Zhu Zhong‑Liang Li Hong‑Xin Luo shang‑yu si yun‑Ping Zhu Li Zhao Kuan Ren Feng Wang Rong‑Qing Yi shanghai Synchrotron Radiation Facility(SSRF) Shanghai Institute of Applied PhysicsChinese Academy of Sciences(CAS)Shanghai 201203China Key Laboratory of Advanced Micro‑Structured Materials Ministry of EducationSchool of Physics and EngineeringTongji UniversityShanghai 200092China State Key Laboratory of Surface Physics Department of PhysicsFudan UniversityShanghai 200438China Thin‑Film Optics Laboratory Hongce Optoelectronics LtdSuzhou 215431China Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900China

Multilayer interference mirrors play a pivotal role in spectroscopic diagnostic systems,which probe electron temperature and density during inertial confinement fusion *** this study,aperiodic Mo/B_(4)C multilayer mirrors of varied thick-nesses were investigated for X-ray plasma diagnostics at the 9.67-keV W-Lβ*** thickness distribution of the aperiodic multilayers was designed using the first Bragg diffraction condition and then optimized through a simplex algorithm to realize a narrow bandwidth and consistent spectral *** enhance spectral accuracy,further refinements were undertaken by matching the grazing incidence X-ray reflectivity data with actual structural parameters.X-ray reflectivity measurements from the SSRF synchrotron radiation facility on the optimized sample showed a reflectivity of 29.7±2.6%,flat-band range of 1.3 keV,and bandwidth of 1.7 keV,making it suitable for high-temperature plasma *** study explored the potential of predicting the 9.67 keV reflectivity spectrum using the fitting data from the grazing incidence X-ray reflectivity curves at 8.05 ***,the short-term thermal stability of an aperiodic multilayer was assessed using temperature-dependent in situ X-ray *** in the reflectivity spectrum during annealing were attributed to interdiffusion and interfacial *** research team recommends the aperiodic Mo/B_(4)C multilayer mirror for operations below 300℃.

关键词： X-ray multilayer mirror Aperiodic multilayer Flat response Sputtering deposition Synchrotron radiation

Intensity correlation properties of x-ray beams split with Laue diffraction

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Chinese Physics B 2024年第1期33卷 379-383页

作者：赵昌哲司尚禹张海鹏薛莲李中亮肖体乔 shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Beam splitting is one of the main approaches to achieving x-ray ghost imaging, and the intensity correlation between diffraction beam and transmission beam will directly affect the imaging quality. In this paper, we investigate the intensity correlation between the split x-ray beams by Laue diffraction of stress-free crystal. The analysis based on the dynamical theory of x-ray diffraction indicates that the spatial resolution of diffraction image and transmission image are reduced due to the position shift of the exit beam. In the experimental setup, a stress-free crystal with a thickness of hundredmicrometers-level is used for beam splitting. The crystal is in a non-dispersive configuration equipped with a double-crystal monochromator to ensure that the dimension of the diffraction beam and transmission beam are consistent. A correlation coefficient of 0.92 is achieved experimentally and the high signal-to-noise ratio of the x-ray ghost imaging is *** of this paper demonstrate that the developed beam splitter of Laue crystal has the potential in the efficient data acquisition of x-ray ghost imaging.

关键词： x-ray ghost imaging beam splitting with Laue diffraction intensity correlation dynamical theory of x-ray diffraction

The MING proposal at SHINE:megahertz cavity enhanced X‑ray generation

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Nuclear Science and Techniques 2023年第1期34卷 51-85页

作者： Nan‑Shun Huang Zi‑Peng Liu Bang‑Jie Deng Zi‑Han Zhu Shao‑Hua Li Tao Liu Zheng Qi Jia‑Wei Yan Wei Zhang Sheng‑Wang Xiang Yang‑Yang Lei Ya Zhu Yong‑Zhou He Qi‑Bing yuan Fei Gao Rong‑Bing Deng Sen Sun Zhi‑Di Lei Zhi‑Qiang Jiang Meng‑Qi Duan yuan Zhuan Xue‑Fang Huang Peng‑Cheng Dong Zhong‑Liang Li shang‑yu si Lian Xue si Chen Yong‑Fang Liu Ya‑Jun Tong Hai‑Xiao Deng Zhen‑Tang Zhao Zhangjiang Laboratory Shanghai 201210China School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049ShaanxiChina shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China European XFEL Schenefeld 22869Germany shanghaiTech University Shanghai 201210China

The cavity-based X-ray free-electron laser(XFEL)has promise in producing fully coherent pulses with a bandwidth of a few meV and very stable intensity,whereas the currently existing self-amplified spontaneous emission(SASE)XFEL is capable of generating ultra-short pulses with chaotic *** general,a cavity-based XFEL can provide a spectral brightness three orders of magnitude higher than that of the SASE mode,thereby opening a new door for cutting-edge scientific *** the development of superconducting MHz repetition-rate XFEL facilities such as FLASH,European-XFEL,LCLS-II,and SHINE,practical cavity-based XFEL operations are becoming increasingly *** this study,megahertz cavity enhanced X-ray generation(MING)is proposed based on China’s first hard XFEL facility-SHINE,which we refer to as MING@SHINE.

关键词： X-ray free-electron laser Free electron laser oscillator Fully coherent X-ray

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2007-2017年我国妇幼卫生状况分析

中国卫生产业 2020年第17期17卷 184-186,189页

作者：于莹莹尚思宇祝丽玲佳木斯大学公共卫生学院黑龙江佳木斯154007 齐齐哈尔市第一医院黑龙江齐齐哈尔161000

目的通过描述我国2007-2017年妇幼保健指标变化情况并分析其变化趋势,为改善妇幼保健服务水平提供重要依据.方法采用动态数列法描述2007-2017年我国妇幼保健指标变化趋势.结果 2007-2017年全国及城乡的新生儿死亡率平均增长速度分别为... 详细信息

目的通过描述我国2007-2017年妇幼保健指标变化情况并分析其变化趋势,为改善妇幼保健服务水平提供重要依据.方法采用动态数列法描述2007-2017年我国妇幼保健指标变化趋势.结果 2007-2017年全国及城乡的新生儿死亡率平均增长速度分别为:-0.0757、-0.0658、-0.0770;婴儿死亡率平均增长速度分别为:-0.0711、-0.0557、-0.0749;5岁以下儿童死亡率平均增长速度分别为:-0.0606、-0.0556、-0.0611;孕产妇死亡率平均增长速度分别为:-0.0552、-0.0372、-0.059,各指标均呈负增长.结论 2007—2017年全国及城乡妇幼保健指标均呈下降趋势,其中城市变化平稳,农村变化幅度较大,针对妇幼保健服务的区域均衡发展问题应持续加大关注.

关键词：妇幼卫生状况新生儿死亡率婴儿死亡率 5岁以下儿童死亡率孕产妇

相对骨骼肌质量指数对老年维持性血液透析病人骨折的预测价值

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实用老年医学 2022年第7期36卷 725-728页

作者：郁雪雪杨昭尚思雨侯梦李莎海军军医大学第一附属医院(长海医院)手术室上海市200433

目的探究相对骨骼肌质量指数(RSMI)对老年维持性血液透析病人骨折的预测价值。方法选取我院2018年4月至2021年1月收治的163例老年维持性血液透析病人作为研究对象,于病人入院24 h内收集病人的临床资料,检测病人血清全段甲状旁腺激素(iP... 详细信息

目的探究相对骨骼肌质量指数(RSMI)对老年维持性血液透析病人骨折的预测价值。方法选取我院2018年4月至2021年1月收治的163例老年维持性血液透析病人作为研究对象,于病人入院24 h内收集病人的临床资料,检测病人血清全段甲状旁腺激素(iPTH)、白蛋白(ALB)水平及四肢骨骼肌质量(ASMM),并根据ASMM计算RSMI。随访12个月,观察病人是否发生非外力创伤性骨折,并将其分为骨折组及非骨折组,采用多因素Logistic回归分析影响老年维持性血液透析病人骨折的相关因素,绘制ROC曲线分析RSMI对老年维持性血液透析病人骨折的预测价值。结果入组的163例老年维持性血液透析病人均未失访,随访期内发生骨折21例(12.88%)。2组性别、年龄、BMI、吸烟史、饮酒史、透析龄、骨密度T值、高血压病人比例差异均无统计学意义(P>0.05);2组糖尿病病人比例、血清ALB水平、iPTH水平、RSMI差异均有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,糖尿病、低水平的RSMI、低血清ALB及iPTH<150 ng/L均为老年维持性血液透析病人骨折的独立危险因素。ROC曲线分析结果显示,RSMI预测老年维持性血液透析病人发生骨折的灵敏度为71.43%,特异度为78.87%,AUC为0.802(95%CI0.697~0.907),最佳截断值为6.44。结论RSMI可有效预测老年维持性血液透析病人骨折的风险,临床治疗中应定期密切监测病人的RSMI。

关键词：维持性血液透析老年人相对骨骼肌质量指数骨折预测效能

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

Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao Hu si Wang Weiqi Zhang Jing Qu Guang-Hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis

Challenges in the management of visual and tactile hallucinations in elderly people

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World Journal of Psychiatry 2025年第1期15卷 185-188页

作者： si-Sheng Huang Division of Geriatric Psychiatry Department of PsychiatryChanghua Christian HospitalChanghua 500Taiwan Department of Post-Baccalaureate Medicine College of MedicineNational Chung Hsing UniversityTaichung 402Taiwan

This letter provides a concise review of the pertinent literature on visual and tactile hallucinations in elderly *** discussion addresses differential diagnoses and potential underlying mechanisms,as well as the psychopathology associated with tactile hallucinations,and emphasizes the necessity for invest-igation into the possibility of coexisting delusional infestation(parasitosis).These symptoms frequently manifest in patients with primary psychotic disorders,organic mental disorders,and substance use *** proposed pathophy-siological mechanisms may involve dopaminergic imbalances and dysfunction of the striatal dopamine transporter.

关键词： Delusional infestation Dementia Haptic hallucination Scratching behavior Tactile hallucination Visual hallucination Alzheimer’s disease