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Soller slits automatic focusing method for multi-element fluorescence detector

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Nuclear Science and Techniques 2016年第5期27卷 179-187页

作者： Ya-Yun Yang qian Gao song-qi gu Hai-Sheng Yu Rui-You Lu Yu-Ying Huang Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049 China

In X-ray absorption fine structure(XAFS) experiments,Soller slits are widely used as filter devices in order to improve the signal to noise *** high accuracy manual focusing operations is a time-consuming process;therefore,this work introduces an automatic focusing method for Soller slits in multi-element fluorescence *** method establishes a relation model between the fluorescence intensity distribution and the coordinates of the fluorescence excitation *** to this relation model,the actual coordinates of the fluorescence excitation point can be deduced from the detected fluorescence intensity distribution and used in focusing *** method has proven to be feasible in an XAFS experiment at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facility.

关键词：荧光检测器聚焦方法狭缝 X射线吸收精细结构 XAFS实验关系模型光强度分布高信噪比

A seven-crystal spectrometer for high-energy resolution X-ray spectroscopy at Shanghai Synchrotron Radiation Facility

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Nuclear Science and Techniques 2024年第9期35卷 82-91页

作者： Bing-Bao Mei Liang-Xin Wang song-qi gu Xiao-Zhi Su Shuo Zhang Yao Wei Jing-Yuan Ma Zheng Jiang Fei song Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201800China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facility(SSRF).This spectrometer was utilized to implement X-ray emission spectroscopy(XES),high-energy resolution fluorescence-detected X-ray absorption spectroscopy(HERFD-XAS),and resonant inelastic X-ray *** spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles,adopting an area detector to increase the solid angle to 1.75%of 4πsr,facilitating the study of low-concentrate systems under complex reaction *** under the atmosphere pressure,the spectrometer covers the energy region from 3.5 to 18 keV,with the Bragg angle ranging from 73°to 86°during vertical *** offers a promised energy resolution of sub-eV(XES)and super-eV(HERFD-XAS).Generally,these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy ***,they provide substantial support for scientific advances in fundamental research.

关键词： X-ray emission spectroscopy High-energy-resolution X-ray spectrometer Johann geometry Energy materials SSRF

Local structural evolutions of CuO/ZnO/Al2O3 catalyst for methanol synthesis under operando conditions studied by in situ quick X-ray absorption spectroscopy

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Nuclear Science and Techniques 2017年第2期28卷 35-43页

作者： Xue-Ping Sun Fan-Fei Sun song-qi gu Jing Chen Xian-Long Du Jian-qiang Wang Yu-Ying Huang Zheng Jiang Shanghai Institute of Applied Physics Chinese Academy of Sciences Zhangjiang Campus Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049China

In situ quick X-ray absorption spectroscopy(QXAFS) at the Cu and Zn K-edge under operando conditions has been used to unravel the Cu/Zn interaction and identify possible active site of CuO/ZnO/Al_2O_3 catalyst for methanol synthesis. In this work, the catalyst, whose activity increases with the reaction temperature and pressure, was studied at calcined, reduced, and reacted conditions. TEM and EDX images for the calcined and reduced catalysts showed that copper was distributed uniformly at both conditions. TPR profile revealed two reduction peaks at 165 and 195 °C for copper species in the calcined catalyst. QXAFS results demonstrated that the calcined form consisted mainly of a mixed Cu O and Zn O, and it was progressively transformed into Cu metal particles and dispersed Zn O species as the reduction treatment. It was demonstrated that activation of the catalyst precursor occurred via a Cu^+intermediate, and the active catalyst predominantly consisted of metallic Cu and Zn O evenunder higher pressures. Structure of the active catalyst did not change with the temperature or pressure, indicating that the role of the Zn was mainly to improve Cu *** indicates the potential of QXAFS method in studying the structure evolutions of catalysts in methanol synthesis.

关键词： In situ Quick X-ray absorption spectroscopy CuO/ZnO/Al2O3 catalyst Operando condition

Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury

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Neural Regeneration Research 2025年第10期20卷 2807-2822页

作者： Xizi song Ruixin Li Xiaolei Chu qi Li Ruihua Li qingwen Li Kai-Yu Tong Xiaosong gu Dong Ming Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Haihe Laboratory of Brain-Machine Interface and Human-Machine Fusion TianjinChina Department of Rehabilitation Tianjin University Tianjin HospitalTianjinChina Department of Hand Microsurgery Tianjin University Tianjin HospitalTianjinChina School of Exercise and Health Tianjin University of SportTianjinChina Department of Biomedical Engineering the Chinese University of Hong KongHong Kong Special Administrative RegionChina

Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and *** on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target *** has led to restrictions on current therapeutic *** this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target *** peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal *** nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury *** damage to target organs can occur,including skeletal muscle atrophy and sensory receptor *** then provide a brief review of the research advances in therapeutic approaches to peripheral nerve *** main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical ***,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ ***,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.

关键词： central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach

Potential role of tanycyte-derived neurogenesis in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1599-1612页

作者： guibo qi Han Tang Jianian Hu Siying Kang song qin Department of Anatomy Histologyand EmbryologySchool of Basic Medical SciencesFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina

Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier ***, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could pro

关键词： Alzheimer's disease blood–brain barrier ependymoglial cells hypothalamus metabolic diseases neural stem cells neurogenesis neuroinflammatory diseases neurons tanycyte

Exploration of Gas‑Dependent Self‑Adaptive Reconstruction Behavior of Cu_(2)O for Electrochemical CO_(2)Conversion to Multi‑Carbon Products

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Nano-Micro Letters 2025年第3期17卷 280-296页

作者： Chaoran Zhang Yichuan gu Qu Jiang Ziyang Sheng Ruohan Feng Sihong Wang Haoyue Zhang qianqing Xu Zijian Yuan Fang song State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially ***,we report that CO_(2)accessibility results in a universal self-adaptive structural reconstruction from Cu_(2)O to Cu@CuxO composites,ending with feeding gas-dependent microstructures and catalytic *** CO_(2)-rich atmosphere favors reconstruction for CO_(2)RR,whereas the CO_(2)-deficient one prefers that for hydrogen evolution *** the assistance of spectroscopic analysis and theoretical calculations,we uncover a CO_(2)-induced passivation behavior by identifying a reductionresistant but catalytic active Cu(I)-rich amorphous layer stabilized by*CO ***,we find extra CO production is indispensable for the robust production of *** inverse correlation between durability and FECO/FEC2H4 is disclosed,suggesting that the selfstabilization process involving the absorption of*CO intermediates on Cu(I)sites is essential for durable *** by this insight,we design hollow Cu_(2)O nanospheres for durable and selective CO_(2)RR electrolysis in producing *** work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes.

关键词： CO_(2)reduction reaction Electrocatalysts Cu_(2)O Reconstruction Self-adaptive electrocatalysis

Development of a general circumferentially nonuniform heat transfer fuel rod model for subchannel analysis and application to helical fuel rods

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Science China Technological Sciences 2025年

作者： Junsen FU Junlong LI Xiaowen WANG qi ZHANG Yao XIAO Hanyang gu School of Mechanical Engineering Shanghai Jiao Tong University Key Laboratory of Nuclear Power Systems and Equipment of the Ministry of Education Shanghai Jiao Tong University National Key Laboratory of Nuclear Reactor Technology Nuclear Power Institute of China State Key Laboratory of Nuclear Power Safety Technology and Equipment Shanghai Jiao Tong University

The subchannel analysis method is one of the most crucial transient safety analysis methods in the thermal design of nuclear reactors. The nonuniformity of circumferential heat transfer is slight in conventional pressurized water reactor (PWR)cores, but it is significant in advanced reactors with wire-wrapped or helical fuel rods. Predicting circumferentially nonuniform heat transfer behavior can be challenging owing to the complex geometry of helical fuel rods. In this study, a general circumferentially nonuniform heat transfer fuel rod (GCNF) model is developed to predict the fuel central temperature and circumferential heat flux and wall temperature. This model incorporates a refined two-dimensional fuel conduction model and circumferential nonuniform shape factor, addressing the dual factors contributing to the circumferential nonuniformity of helical fuel rods. An empirical correlation for the nonuniform shape factor is developed based on the computational fluid dynamics (CFD) results, and it is implemented to the subchannel code. The newly developed model is applied to a helical fuel annulus and validated by comparing the prediction results with CFD data. The maximum wall temperature predicted by the code is 1.15°C lower than the value calculated through CFD. In terms of the heat flux, the maximum value at the inner corner is22 kW lower than that obtained from the CFD prediction. The accurate prediction of circumferentially nonuniform heat transfer in helical fuel, concerning the surface heat flux and cladding temperature, addresses existing shortcomings in helical fuel subchannel analysis methods. Additionally, the capability to predict the fuel central temperature is essential for the safety analysis to determine whether fuel rods are melting. The generality of the model framework allows it to be used for the prediction of circumferential nonuniform heat transfer behavior in other types of fuel assemblies.

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Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第01期 337-349页

作者： Meiyun Xu song gu Fulong Chen Zhe Zhao Peng Liu Daoben Hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

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Constructing quasi-2D perovskite to collect hot carriers to reduce open-circuit voltage loss for efficient inverted perovskite solar cells

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Science China Chemistry 2025年

作者： Lei gu Xing Li Chao Wu Yang Feng Chunming Yang Lin song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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