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X-ray fluorescence microtomography based on polycapillary- focused X-rays from laboratory source

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Nuclear Science and Techniques 2018年第6期29卷 85-91页

作者： Bing-Gang Feng Fen Tao Yi-Ming yang Tao Hu Fei-Xiang Wang Guo-Hao Du yan-Ling Xue ya-jun tong Tian-Xi Sun Biao Deng Ti-Qiao Xiao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China Beijing Normal University Beijing 100875 China

X-ray fluorescence microtomography(μXFCT)is a nondestructive analytical technique and has been widely used to nondestructively detect and quantify the elemental composition and distributions in samples. Usually, synchrotron radiation X-rays are used for μXFCT, due to its high flux density. In this paper, a laboratory-sourcebased μXFCT system was developed, in which a polycapillary lens is employed to focus the X-ray beam and improve the flux density. The maximum likelihood expectation maximization algorithm was used to reconstruct the computed tomography slices at a limited number of projections. The experimental results demonstrated that the developed system could reveal the elemental distribution inside the test sample, with an elemental sensitivity of 1000 ppm.

关键词：检查荧光实验室期望最大化算法采购非破坏性同步加速器断层摄影术

First commissioning results of the coherent scattering and imaging endstation at the Shanghai soft X-ray free-electron laser facility

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Nuclear Science and Techniques 2022年第9期33卷 48-58页

作者： Jia-Dong Fan ya-jun tong Yong-Gan Nie Zi-Chen Gao Bo He Hui Luan Dong-Hao Lu Jian-Hua Zhang Di-Fei Zhang Xin-Ye Yuan Jia-Hua Chen Zhi Guo Tao Liu Meng Zhang Chao Feng Hai-Xiao Deng Bo Liu Zhen-Tang Zhao Zhi Liu Huai-Dong Jiang Center for Transformative Science ShanghaiTech UniversityShanghai 201210China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The Shanghai soft X-ray free-electron laser(SXFEL)user facility project started in 2016 and is expected to be open to users by *** aims to deliver ultra-intense coherent femtosecond X-ray pulses to five endstations covering a range of 100–620 eV for ultrafast X-ray *** undulator lines are designed and constructed,based on different lasing modes:self-amplified spontaneous emission and echo-enabled harmonic *** coherent scattering and imaging(CSI)endstation is the first of five endstations to be commissioned *** focuses on high-resolution single-shot imaging and the study of ultrafast dynamic processes using coherent forward scattering *** the single-shot holograms and coherent diffraction patterns were recorded and reconstructed for nanoscale imaging,indicating the excellent coherence and high peak power of the SXFEL and the possibility of‘‘diffraction before destruction’’experiments at the CSI *** this study,we report the first commissioning results of the CSI endstation.

关键词： X-ray free electron laser Coherent diffraction imaging Fourier transform holography Single-shot imaging Phase retrieval

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

Apolipoprotein E elicits targetdirected miRNA degradation to maintain neuronal integrity

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Neural Regeneration Research 2025年第9期20卷 2577-2578页

作者： Jiazi Tan Chin-tong Ong Temasek Life Sciences Laboratory National University of SingaporeSingapore Department of Biological Sciences National University of SingaporeSingapore

Apolipoprotein E has diverse functions in neurons:Apolipoprotein E(ApoE)is a glycoprotein that primarily regulates lipid metabolism and transport in the central nervous *** are three predominant human ApoE protein isoforms with cysteine and arginine substitutions at amino acid positions 112 and 158 that impact their lipidation and related functions(Flowers and Rebeck,2020).ApoE2 is characterized by Cys112 and Cys158,ApoE3 by Cys112 and Arg158,whereas ApoE4 contains Arg112 and Arg158.

关键词： metabolism glycoprotein maintain

Reverse modulation of defect density of Ce-MOF-808 by solventassisted ligand exchange for dicyclopentadiene hydrogenation

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Science China Chemistry 2025年

作者： Danfeng Zhao Fajie Hu Rushuo Li Xinmeng Xu Zhaokun Wang Zuoshuai Xi jun tong Xiubing Huang Ge Wang Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing

Defect engineering is a pivotal strategy for tailoring the electronic structure and physicochemical properties of catalysts, yet the straightforward manipulation of defect density in porous materials presents a current challenge. In this work, we achieved precise control over the coordination unsaturated site（CUS） content and pore architecture of Ce-MOF-808 by employing 2-fluorobenzoic acid（2-FBA） as a modifier. Leveraging the p Kadisparities among three ligands（1,3,5-tricarboxylic benzoic acid,formic acid, and 2-FBA）, we preserved the spn topology of Ce-MOF within an aqueous system, while realizing partial substitution of the auxiliary ligands and saturation of the CUS. The amount of 2-FBA was negatively correlated with the number of ligand defects, and the consequent decrease in Ce3+content and the increase in the number of ligand linkages also induced crystal structure transformation. The modulation of the defect structure was correlated with the catalytic performance of dicyclopentadiene（DCPD） hydrogenation reaction, in which Ce-MMF0.15, constructed by the modulation of 0.15 mol amount of 2-fluorobenzoic acid, exhibited an optimal ligand defect density and micro-mesoporous structure, enabling almost complete conversion of DCPD at 100 ℃ and 2 MPa. This article also elucidates the correlation between the regulation of defect density and the accessibility of frustrated Lewis pair（FLP） active sites, guiding the application of novel porous intrinsic FLP materials in hydrogenation catalysis.

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Liquid refractive index measurement method based on orthogonal polarization laser self-mixing interference

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Optoelectronics Letters 2025年

作者： ZHAO yan WANG Haipeng DU Shengzhi tong Jigang KANG jun School of Electrical Engineering and Automation， Tianjin University of Technology Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems Department of Electrical Engineering， Tshwane University of Technology

In this paper， a novel method combining orthogonal polarization laser self-mixing interference is proposed. The method utilizes a rotating cuvette to measure the refractive index of liquids at different concentrations. The cuvette is filled with the liquid to be measured and rotated by a certain angle. The change in the number of interference fringes， caused by comparing an empty cuvette with a liquid-filled cuvette， is used to calculate the refractive index of the liquid. A four-fold logic subdivision algorithm is then used to improve measurement resolution. The experimental results show that for pure water and different NaCl and glucose solutions concentrations， the average relative errors are 0.47%， 0.59%， and 2.17%， respectively， with the maximum relative error within ±2.54%. The standard deviation of all solutions is less than 3.4%.

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Targeting Epac2 and GluA3-containing AMPARs:a novel therapeutic strategy for Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3223-3224页

作者： tong Zhang Martina Schmidt Department of Molecular Pharmacology Groningen Research Institute of PharmacyUniversity of GroningenGroningenThe Netherlands School of Pharmacy Tianjin Medical UniversityTianjinChina

Alzheimer's disease(AD)is a neurodegenerative disease that manifests progressive decline in memory and *** the early stage of AD,memory retrieval is impaired preceding memory acquisition and consolidation(Roy et al.,2016).Prior to the onset of symptoms,pathological amyloid-β(Aβ)plagues and tau protein tangles accumulate in extracellular and intracellular spaces,respectively,leading to *** these hallmark pathologies,Aβ is proposed to be the primary etiology by triggering a cascade of pathogenic events,including neuroinflammation,oxidative stress,tau hyperphosphorylation,synaptic/neuronal dysfunction,and neuronal death(Zhang et al.,2023b).

关键词： Alzheimer impaired Aβ

Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-Jin Jiang Ji Yu Mao-jun yao Yun-tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： tongyue Li Ziliang Xie Wenjiao Zhou Huan tong Dawen yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics