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BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

Nuclear Science and Techniques 2024年第7期35卷 68-78页

作者： Zhi-Jun Wang Si-Sheng Wang Zheng-huang Su Li yu yu-Zhu Wang Bo Sun Wen Wen Xing-yu Gao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Science Beijing100049China

A Laue microdiffraction beamline(BL03HB) was constructed at the Shanghai Synchrotron Radiation Facility(SSRF).This beamline features two consecutive focusing points in two different sectors within its end station, the first dedicated to protein crystallography and the other tailored to materials science applications. Based on a superbend dipole magnet with a magnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick-Baez mirrors to achieve a micro white beam as small as 4.2 μ m ×4.3 μ m at the first sector and 0.9 μ m ×1.3 μ m at the second sector in the standard beamline operation mode at SSRF. The X-ray microbeam in the two sectors can be easily switched between monochromatic and white beams by moving a four-bounce monochromator in or out of the light path, respectively. In the protein crystallography sector, white-beam Laue microdiffraction was demonstrated to successfully determine the structure of protein crystals from only a few images of diffraction data collected by a Pilatus 2 M area detector. In the materials science sector,the white-beam Laue diffraction was collected in a reflection geometry using another Pilatus 2 M area detector, which could map the microstructural distribution on the sample surface by scanning the samples. In general, the BL03HB beamline promotes the application of Laue microdiffraction in both protein crystallography and materials science. This paper presents a comprehensive overview of the BL03HB beamline, end station, and the first commission results.

关键词： Crystallography White-beam Laue microdiffraction Beamline Synchrotron

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Stability analysis of longwall top-coal caving face in extra-thick coal seams based on an innovative numerical hydraulic support model

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International Journal of Mining Science and Technology 2024年第4期34卷 491-505页

作者： Jun Guo Wenbo huang Guorui Feng Jinwen Bai Lirong Li Zi Wang Luyang yu xiaoze Wen jie Zhang Wenming Feng College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Shanxi Province for Mine Rock Strata Control and Disaster Prevention Taiyuan University of TechnologyTaiyuan 030024China Shanxi Coking Coal Group Co. Ltd.Taiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China

The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining *** view of the fact that most of the existing numerical simulation methods construct virtual elements and stress servo control to approximately replace the hydraulic support problem,this paper establishes a new numerical model of hydraulic support with the same working characteristics as the actual hydraulic support by integrating numerical simulation software Rhino,Griddle and FLAC3D,which can realize the simulation of different working *** on this model,the influence mechanism of the supporting strength of hydraulic support on surrounding rock stress regulation and coal stability in front of the top coal caving face in extra thick coal seam were ***,under different support intensity,the abutment pressure of the bearing coal and the coal in front of it presents the “three-stage”evolution *** influence range of support intensity is 15%–30%.Secondly,1.5 MPa is the upper limit of impact that the support strength can have on the front coal failure ***,within a displacement range of 2.76 m from the coal wall,a support strength of1.5 MPa provides optimal control of the horizontal displacement of the coal.

关键词： Extremely thick coal seam Fully mechanized top coal caving Support strength Support-surrounding rock interaction

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Ambient-Condition Strategy for Production of Hollow Ga_(2)O_(3)@rGO Crystalline Nanostructures Toward Efficient Lithium Storage

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Energy & Environmental Materials 2024年第2期7卷 75-82页

作者： Dongdong Zhang Qiliang Wei Haili huang Lan Jiang jie Teng Ruizhi yu Qing Zhang Shengxing Liu Lin Wang Weiyou Yang Institute of Micro/Nano Materials and Devices Ningbo University of TechnologyNingbo 315211China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Crystallineγ-Ga_(2)O_(3)@rGO core-shell nanostructures are synthesized in gram scale,which are accomplished by a facile sonochemical strategy under ambient *** are composed of uniformγ-Ga_(2)O_(3)nanospheres encapsulated by reduced graphene oxide(rGO)nanolayers,and their formation is mainly attributed to the existed opposite zeta potential between the Ga_(2)O_(3)and *** as-constructed lithium-ion batteries(LIBs)based on as-fabricatedγ-Ga_(2)O_(3)@rGO nanostructures deliver an initial discharge capacity of 1000 mAh g^(-1)at 100 mA g^(-1)and reversible capacity of 600 mAh g^(-1)under 500 mA g^(-1)after 1000 cycles,respectively,which are remarkably higher than those of pristineγ-Ga_(2)O_(3)with a much reduced lifetime of 100 cycles and much lower *** situ XRD and XPS analyses demonstrate that the reversible LIBs storage is dominant by a conversion reaction and alloying mechanism,where the discharged product of liquid metal Ga exhibits self-healing ability,thus preventing the destroy of ***,the rGO shell could act robustly as conductive network of the electrode for significantly improved conductivity,endowing the efficient Li storage *** work might provide some insight on mass production of advanced electrode materials under mild condition for energy storage and conversion applications.

关键词： ambient condition core-shell nanostructures Ga_(2)O_(3) Li-ion batteries rGO

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Construction of a multifunctional Ti3C2Tx MXene/g-C3N4 artificial protective layer for dendrite-free aqueous Zn-ion batteries

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Rare Metals 2024年第10期43卷 4992-5004页

作者： Wei-Wei Wang Rui huang yu Tao Peng He Su-Xing Tuo yu-Jian Bian Rui-Ting Hu Jun Yan Yan-jie Liang Wen-Chao Zhang The Key Laboratory of Digital Flavour Research of Hunan China Tobacco Industry Co. Ltd College of Metallurgy and Environment Central South University College of Chemistry and Chemical Engineering Central South University

The electrochemical utilization of Zn anodes in aqueous batteries is hampered by the intricate and interconnected issues of Zn dendrite growth,H2evolution and Zn corrosion *** this study,a multifunctional protective layer comprising MXene and graphitic carbon nitride （g-C3N4） was constructed using a self-assembly *** MXene/g-C3N4protective layer exhibited robust zincophilic characteristics,which facilitated a uniform distribution of the electric field and ensured a sufficient influx of Zn2+.This reduces the Zn2+nucleation barrier and prevents dendrite *** addition,the hydrophobic nature of the protective layer,coupled with its negative charge,can repel SO42-and select water molecules from the electrolyte,which aids in mitigating corrosion and *** symmetric Zn cell coated with the MXene/g-C3N4protective layer showed remarkable stability,achieving over 2000 h of reversible cycling at1 mA·***,the MXene/g-C3N4-coated Zn anode paired with a sodium-doped V2O5cathode （NVO）exhibited enhanced cycling capability over 1500 cycles.

关键词： Artificial protective layers Dendrite-free Zn anodes g-C3N4 Interface stability Ti3C2Tx MXene

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High-sensitive nonthermally coupled upconversion for ultralow temperature sensing

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Journal of Rare Earths 2024年第11期42卷 2027-2032页

作者： Zhiyuan Cai Zhengce An Haozhang huang yu Zhao Bo Zhou State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniquesand Institute of Optical Communication MaterialsSouth China University of Technology

Upconversion based nanothermometry has received much attention due to its merits of stability,narrow band emission and rich emission ***,the previous works are mainly focused on the emissions from thermally coupled energy levels which is theoretically limited by Boltzmann distribution theory with resultant low temperature sensitivity in particular at ultralow *** we report a LiYF4:Yb/Ho@LiYF4core-shell nanostructure to improve the sensitivity at low temperatures by taking advantage of non-thermally coupled energy levels of Ho3+.In detail,the green upconversion emission of Ho3+shows an increase with reducing temperature while its red upconversion emission presents a decline during the same *** is primarily due to the suppression of the non-radiative multiphonon relaxation occurred at the green emitting levels（5F4,5S2） and the intermediate level（5I6） at low *** a feature contributes to a high relative sensitivity of 7.17%/K at 11 K,much higher than reported *** results provide a promising candidate for the development of nanothermometer with high-sensitive low-temperature sensing performance.

关键词： Nanothermometry Nonthermally coupled emissions Rare earths Ultralow temperature Upconversion

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Engineering Ru（N^N）3-modified covalent organic framework for photocatalytic olefin epoxidation

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Science China Chemistry 2024年第11期67卷 3719-3728页

作者： Yan-Lin Li Sheng-Li huang Guo-yu Yang Key Laboratory of Cluster Science (Ministry of Education) Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical Engineering Beijing Institute of Technology

Photocatalytic olefin oxidation using air as an oxidant is an environmentally friendly method for producing epoxides. Covalent organic frameworks（COFs） have emerged as promising photocatalysts in various organic synthesis reactions. The combination of tri-（2-pyridinal aldehyde）-containing precursor with 4,4’,4’’-（1,3,5-triazine-2,4,6-triyl）trianiline generated（N^N）-I-COF. Via imine-to-quinoline transformation and coordination anchorage of Ru（N^N）3unit, Ru（N^N）3@Q-COF was obtained with improved chemical stability, skeleton conjugation, and novel photochemical characteristics, and demonstrated excellent photocatalytic activity in olefin epoxidation with a wide range of substrates. The presence of H2O played a crucial role in the formation of reactive oxygen species（ROSs）, which in turn influenced the olefin oxidation process. The hydrophilicity of Ru（N^N）3facilitated the approach of H2O and O2to the photogenerated charges, thereby promoting ROSs generation. The lipophilicity of Q-COF allowed for the absorption of olefin substrates, and its nano-channels increased encountering possibility between olefins and ROSs. Consequently, Ru（N^N）3@Q-COF provided an intriguing platform for olefin photooxidation and could be recycled multiple times without any degradation in performance. This report revealed that the conversion of classical ROSs into less potent oxidants with rapid kinetic rates played a crucial role in achieving highly efficient and selective epoxidation of terminal olefins.

关键词： polypyridyl Ru covalent organic framework olefin epoxidation photocatalysis

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Challenges and strategies of chlorine inhibition in anode systems for seawater electrolysis

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Science China Chemistry 2024年第10期67卷 3198-3208页

作者： Chuqiang huang Zhouzhou Wang Shaojun Cheng yunpeng Liu Binglu Deng Shaoyi Xu Luo yu Ying yu School of Materials Science and Hydrogen Energy Foshan UniversityFoshan 528000China Institute of Nanoscience and Nanotechnology College of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079China Department of Physics and Texas Center for Superconductivity at the University of Houston(TcSUH) University of HoustonHoustonTX 77204USA Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430074China

Seawater electrolysis for green hydrogen production is one of the key technologies for achieving carbon ***,in anode systems,the chloride ions(Cl^(-))in seawater will trigger an undesired chlorine evolution reaction(CER)that competes with an oxygen evolution reaction(OER),resulting in inferior OER activity and ***,the corrosive Cl^(-)and its derivative products will corrode anodes during seawater electrolysis,leading to poor ***,great efforts have been devoted to developing efficient strategies for chlorine inhibition to improve the activity,selectivity,and stability of anode ***,focusing on chlorine inhibition,we present a mini review to comprehensively and concisely summarize the recent progress in anode systems for boosting seawater *** particular,two strategies of physical and chemical regulation to inhibit Cl^(-)are summarized in some representative ***,some challenges and future opportunities in anode systems for seawater electrolysis are *** mini review aims to shed light on designing highly efficient anode materials for seawater electrolysis.

关键词： seawater electrolysis anode systems chlorine inhibition physical regulation chemical regulation

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Jigsaw-Sketch: a fast and accurate algorithm for finding top-k elephant flows in high-speed networks

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Science China(Information Sciences) 2024年第4期67卷 113-130页

作者： Boyu ZHANG He huang yu-E SUN Yang DU Dan WANG School of Computer Science and Technology Soochow University School of Rail Transportation Soochow University

Finding top-k elephant flows in high-speed networks is one of the most fundamental network measurement tasks. It is more challenging than per-flow size estimation since the IDs and sizes of top-k flows must be tracked simultaneously. Most existing studies only record the IDs of a small number of elephant flows to fit their estimators in the extremely limited high-speed on-chip memory. However, these solutions need too many memory accesses when a packet arrives to track the elephant flows with high accuracy, which limits their practicability. Therefore, this paper proposes Jigsaw-Sketch, a new algorithm to find the top-k elephant flows with much fewer memory accesses while achieving high memory efficiency and accuracy. In this design, we propose a novel two-stage jigsaw storage scheme, which can capture the candidate top-k flows from massive network steams efficiently, and further find the top-k elephant flows with high memory efficiency and only a few memory accesses for each packet. Extensive experimental results based on real network traces show that Jigsaw-Sketch improves the packet processing throughput by at least 86%, while achieving smaller memory footprints and higher accuracy compared to the SOTA.

关键词： sketch top-$k$ network measurement elephant flow high-speed networks

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Effect of Iron on the Stability of Rhodochrosite at the Topmost Lower Mantle Conditions

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Journal of Earth Science 2024年第2期35卷 504-513页

作者： Tianlei Zhai Fei Qin Shengxuan huang Shan Qin yu Gong Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing100871China School of Earth Sciences and Resources China University of GeosciencesBeijing100083China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

Carbonates are viewed as the principal oxidized carbon carriers during subduction,and thus the stability of subducted carbonates has significant implications for the deep carbon *** we investigate the high pressure-temperature behaviors of rhodochrosite in the presence of iron up to∼34 GPa by in-situ X-ray diffraction and ex-situ Raman *** relatively low temperature below∼1500 K,MnCO_(3)breaks down into MnO and CO_(2).Upon heating to∼1800 K,however,the MnCO_(3)-Fe^(0)reactions occur with the formation of Mn_(3)O_(4),Fe^(O)and reduced carbon.A'three-stage'reaction mechanism is proposed to understand the kinetics of the carbon-iron-manganese redox *** results suggest that Fe^(0)can serve as a reductant to greatly affect the stability of rhodochrosite,which implies that the effect of Fe-metal should be seriously considered for the high pressure-temperature behaviors of other predominant carbonates at Earth's mantle conditions,particularly at depths greater than∼250 km.

关键词： deep carbon cycle rhodochrosite reduced mantle diamond formation high pressure tectonics geochemistry

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Multiple regulatory roles of the transfer RNA-derived small RNAs in cancers

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Genes & Diseases 2024年第2期11卷 597-613页

作者： yu Zhang Xinliang Gu Yang Li yuejiao huang Shaoqing Ju Medical School of Nantong University Nantong UniversityNantongJiangsu 226001China Department of Laboratory Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu 226001China Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu 226001China Department of Medical Oncology Affiliated Hospital of Nantong UniversityNantongJiangsu 226001China

With the development of sequencing technology,transfer RNA(tRNA)-derived small RNAs(tsRNAs)have received extensive attention as a new type of small noncoding *** on the differences in the cleavage sites of nucleases on tRNAs,tsRNAs can be divided into two categories,tRNA halves(tiRNAs)and tRNA-derived fragments(tRFs),each with specific subcellular ***,the biogenesis of tsRNAs is tissue-specific and can be regulated by tRNA *** this review,we first elaborated on the classification and biogenesis of *** summarizing the latest mechanisms of tsRNAs,including transcriptional gene silencing,post-transcriptional gene silencing,nascent RNA silencing,translation regulation,rRNA regulation,and reverse transcription regulation,we explored the representative biological functions of tsRNAs in ***,this review summarized the clinical value of tsRNAs in cancers,thus providing theoretical support for their potential as novel biomarkers and therapeutic targets.

关键词： Biogenesis Biological function Cancer Mechanism Therapeutic strategy tsRNAs

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