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Nano Research 2024年第7期17卷 5914-5921页

作者： Chun-Ying Chen Qi-Jie mo Fu-Zhen Li Hai-Li Song Li Zhang moE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(moF)of PCN-222(PCN=porous coordination network),and then applied the resultant moF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

An efficient labeled memory system for learned indexes

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Fundamental Research 2024年第3期4卷 651-659页

作者： Yuxuan mo Jingnan Jia Pengfei Li Yu Hua Huazhong University of Science and Technology Wuhan 430074China

The appearance and wide use of memory hardware bring significant changes to the conventional vertical memory hierarchy that fails to handle contentions for shared hardware resources and expensive data *** deal with these problems,existing schemes have to rely on inefficient scheduling strategies that also cause extra temporal,spatial and bandwidth *** on the insights that the shared hardware resources trend to be uniformly and hierarchically offered to the requests for co-located applications in memory systems,we present an efficient abstraction of memory hierarchies,called Label,which is used to establish the connection between the application layer and underlying hardware *** on labels,our paper proposes LaMem,a labeled,resource-isolated and cross-tiered memory system by leveraging the way-based partitioning technique for shared resources to guarantee QoS demands of applications,while supporting fast and low-overhead cache repartitioning ***,we customize LaMem for the learned index that fundamentally replaces storage structures with computation models as a case study to verify the applicability of *** results demonstrate the efficiency and efficacy of LaMem.

关键词： Heterogeneous memory system Cache hierarchy Data movement Resource contention Learned index

The effect of friction block hole configurations on the brake tribological performance of high-speed trains

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Friction 2024年第10期12卷 2241-2258页

作者： Yuanke WU Wei CHEN Youguang ZHU Zaiyu XIANG Honghua QIAN Jiliang mo Zhongrong ZHOU Tribology Research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China China Railway Engineering Equipment Group Co. Ltd.Zhengzhou 450016China

Three triangular friction block configurations are commonly employed in high-speed train brake systems,namely,unperforated,perforated configuration with one circular hole,and perforated with three circular *** this study,we adopted these friction block types to investigate the effect of perforated friction block configurations on the brake performance of high-speed trains based on a self-developed brake test *** results indicate the significant impact of the number of the holes on the wear behavior,temperature distribution,and vibration characteristics of the brake *** friction surface of the unperforated block is covered by wear debris,while the perforated blocks produce less wear ***,the one-hole block exhibits a more uniform temperature distribution and better vibration behavior than that with three *** friction brake is a dynamic process,during which separation and attachment between the pad and disc alternatively occur,and the perforated structure on the friction block can both trap and expel the wear debris.

关键词： high-speed train block brake performance wear debris flow

Recent progress in Ni-rich layered oxides and related cathode materials for Li-ion cells

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International Journal of Minerals,Metallurgy and Materials 2024年第11期31卷 2345-2367页

作者： Boyang Fu Maciej moździerz Andrzej Kulka Konrad Świerczek Faculty of Energy and Fuels AGH University of Krakowal.A.Mickiewicza 3030-059 KrakowPoland AGH Centre of Energy AGH University of Krakowul.Czarnowiejska 3630-054 KrakowPoland

Undoubtedly,the enormous progress observed in recent years in the Ni-rich layered cathode materials has been crucial in terms of pushing boundaries of the Li-ion battery(LIB)*** achieved improvements in the energy density,cyclability,charging speed,reduced costs,as well as safety and stability,already contribute to the wider adoption of LIBs,which extends nowadays beyond mobile electronics,power tools,and electric vehicles,to the new range of applications,including grid storage *** numerous published papers and broad reviews already available on the subject of Ni-rich oxides,this review focuses more on the most recent progress and new ideas presented in the literature *** covered topics include doping and composition optimization,advanced coating,concentration gradient and single crystal materials,as well as innovations concerning new electrolytes and their modification,with the application of Ni-rich cathodes in solid-state batteries also *** cathode materials are briefly mentioned,with the high-entropy approach and zero-strain concept presented as well.A critical overview of the still unresolved issues is given,with perspectives on the further directions of studies and the expected gains provided.

关键词： lithium-ion batteries cathode materials nickel-rich layered oxides recent progress critical issues improvement strategies

Reconstruction using artificial intelligence,a promising way to explore the cosmic web

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 179-179页

作者： Houjun mo Department of Astronomy University of MassachusettsAmherst MA 01003USA

One of the most important goals in modern cosmology is to understand the large-scale mass distribution of the universe(the cosmic web),and how galaxies form and evolve in the ecosystem of the cosmic *** this is done by large redshift surveys of galaxies,which can be used to trace the large-scale structure and to sample the properties of galaxies.

关键词： galaxies cosmic universe

Enabling built-in electric fields on rhenium-vacancy-rich heterojunction interfaces of transition-metal dichalcogenides for pH-universal efficient hydrogen and electric energy generation

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Carbon Energy 2024年第9期6卷 195-209页

作者： Benzhi Wang Lixia Wang Ji Hoon Lee Tayirjan Taylor Isimjan Hyung mo Jeong Xiulin Yang Guangxi Key Laboratory of Low Carbon Energy Materials School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilinChina Department of Smart Fab.Technology School of Mechanical EngineeringSungkyunkwan UniversitySuwonRepublic of Korea School of Materials Science and Engineering Kyungpook National UniversityDaeguRepublic of Korea Saudi Arabia Basic Industries Corporation(SABIC)at King Abdullah University of Science and Technology(KAUST) ThuwalSaudi Arabia

most advanced hydrogen evolution reaction(HER)catalysts show high activity under alkaline ***,the performance deteriorates at a natural and acidic pH,which is often problematic in practical ***,a rhenium(Re)sulfide–transition-metal dichalcogenide heterojunc-tion catalyst with Re-rich vacancies(NiS_(2)-ReS_(2)-V)has been *** optimized catalyst shows extraordinary electrocatalytic HER performance over a wide range of pH,with ultralow overpotentials of 42,85,and 122 mV under alkaline,acidic,and neutral conditions,***,the two-electrode system with NiS_(2)-ReS_(2)-V1 as the cathode provides a voltage of 1.73 V at 500 mA cm^(-2),superior to industrial ***,the open-circuit voltage of a single Zn–H_(2)O cell with NiS_(2)-ReS_(2)-V1 as the cathode can reach an impressive 90.9% of the theoretical value,with a maximum power density of up to 31.6 mW cm^(-2).moreover,it shows remarkable stability,with sustained discharge for approximately 120 h at 10 mA cm^(-2),significantly outperforming commercial Pt/C catalysts under the same conditions in all aspects.A series of systematic characterizations and theoretical calculations demonstrate that Re vacancies on the heterojunction interface would generate a stronger built-in electric field,which profoundly affects surface charge distribution and subsequently enhances HER performance.

关键词： built-in electric field electrocatalysts hydrogen evolution reaction self-powered system water splitting Zn-H_(2)O cell

Magnetic properties and magnetocaloric effects in Eu(Ti,Nb,Mn)O_(3) perovskites

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Journal of Rare Earths 2024年第8期42卷 1560-1567,I0006页

作者： Junfeng Wang Huicai Xie Quanyi Liu Zhihong Hao Zhaojun mo Qi Fu Xinqiang Gao Jun Shen Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China School of Rare Earth and New Materials Engineering Gannan University of Science and TechnologyGanzhou341000China Department of Energy and Power Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

In perovskite EuTiO_(3),the magnetic characteristics and magnetocaloric effect(MCE) can be flexibly regulated by converting the magnetism from antiferromagnetic to *** the present work,a series of Eu(Ti,Nb,Mn)O_(3) compounds,abbreviated as ETNmo for convenience of description,was fabricated and their crystallography,magnetism together with cryogenic magnetocaloric effects were systematically *** crystallographic results demonstrate the cubic perovskite structure for all the compounds,with the space group of *** magnetic phase transitions are observed in these second-order phase transition(SOPT) *** joint substitution of elements Mn and Nb can considerably manipulate the magnetic phase transition process and magnetocaloric performance of the ETNmo *** the Mn content increases,gradually widened-ΔS_(M)-T curves are obtained,and two peaks with a broad shoulder are observed in the-ΔS_(M)-T curves for Δμ_(0)H≤0-1 *** a field change of 0-5 T,the values of maximum magnetic entropy change(-ΔS_(M)^(max)) and refrigeration capacity(RC) are evaluated to be 34.7 J/(kg·K) and 364.9 J/kg for EuTi_(0.8625)Nb_(0.0625)Mn_(0.075)O_(3), 27.8 J/(kg·K) and367.6 J/kg for EuTi_(0.8375)Nb_(0.0625)Mn_(0.1)O_(3),23.2 J/(kg·K) and 369.2 J/kg for EuTi_(0.8125)Nb_(0.0625)Mn_(0.125)O_(3),17.1 J/(kg·K) and 357.6 J/kg for EuTi_(0.7875)Nb_(0.0625)Mn_(0.15)O_(3),*** co nsiderable MCE parameters make the ETNmo compounds potential candidates for cryogenic magnetic refrigeration.

关键词： ETNmo perovskites Cryogenic refrigeration Magnetic phase transition Magnetocaloric effect Rare earths

Coupling WO_(3-x) dots-encapsulated metal-organic frameworks and template-free branched polymerization for dual signal-amplified electrochemiluminescence biosensing

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Chinese Chemical Letters 2024年第4期35卷 469-474页

作者： Fei Yin Erli Yang Xue Ge Qian Sun Fan mo Guoqiu Wu Yanfei Shen Medical School Southeast UniversityNanjing 210009China Center of Clinical Laboratory Medicine Zhongda HospitalSoutheast UniversityNanjing 210009China Jiangsu Provincial Key Laboratory of Critical Care Medicine Southeast UniversityNanjing 210009China

Developing accurate and sensitive DNA methyltransferase(MTase) analysis methods is essential for early clinical diagnosis and development of antimicrobial drug targets. In this work, by coupling WO_(3-x) dotsencapsulated metal-organic frameworks(moFs) as co-reactants and terminal deoxynucleotidyl transferase(Td T)-mediated template-free branched polymerization, a dual signal-amplified electrochemiluminescent(ECL) biosensor was constructed to detect DNA adenine methylation(Dam) MTase. The employment of WO_(3-x) dots-encapsulated moFs(i.e., NH_(2)-UIO66@WO_(3-x) ) was not only beneficial for biomolecule conjugation because of the abundant amino groups but also led to a 7-fold enhanced ECL response due to the increased loading of WO_(3-x). moreover, Td T-mediated template-free branched polymerization promoted the capture of ECL emitters on the electrode surface, achieving 20-fold enhanced signal amplification. The presented ECL biosensor demonstrated a low detection limit of 2.4 × 10^(-4)U/m L, and displayed high reliability for the detection of Dam MTase in both spiked human serum and E. coli cell samples, and for the screening of potential inhibitors. This study opens a new avenue for designing a dual signal amplificationbased ECL bioassay for Dam MTase and screening inhibitors in the fields of clinical diagnosis and drug development.

关键词： Dual signal-amplified electrochemiluminescence WO_(3-x)dots moFs Template-free branched polymerization DNA methyltransferase

Bioinspired Closed-loop CPG-based Control of a Robotic Manta for Autonomous Swimming

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Journal of Bionic Engineering 2024年第1期21卷 177-191页

作者： Yiwei Hao Yonghui Cao Yingzhuo Cao Xiong mo Qiaogao Huang Lei Gong Guang Pan Yong Cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo 315103China Key Laboratory of Unmanned Underwater Vehicle Technology of Ministry of Industry and Information Technology Xi'an 710072China

Fish in nature exhibit a variety of swimming modes such as forward swimming,backward swimming,turning,pitching,etc.,enabling them to swim in complex scenes such as coral *** is still difficult for a robotic fish to swim autonomously in a confined area as a real ***,we develop an untethered robotic manta as an experimental platform,which consists of two flexible pectoral fins and a tail fin,with three infrared sensors installed on the front,left,and right sides of the head to sense the surrounding *** generate multiple swimming modes of the robotic manta and online switching of different modes,we design a closed-loop Central Pattern Generator(CPG)controller based on distance information and use a combination of phase difference and amplitude of the CPG model to achieve stable and rapid adjustment of yaw *** verify the autonomous swimming ability of the robotic manta in complex scenes,we design an experimental scenario with a concave *** experimental results show that the robotic manta can achieve forward swimming,backward swimming,in situ turning within the concave obstacle,and finally exit from the area safely while relying on the perception of external obstacles,which can provide insight into the autonomous exploration of complex scenes by the biomimetic robotic ***,the swimming ability of the robotic manta is verified by field tests.

关键词： Biomimetic robotic manta Central Pattern Generator Closed-loop control Backward swimming

Comprehensive treatment of von Hippel-Lindau disease:A case report

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Cancer Innovation 2024年第2期3卷 63-67页

作者： Xuesong Li Zheng mo Zhuo Yu School of Clinical Medicine Tsinghua UniversityBeijingChina Department of Oncology Beijing Tsinghua Changgung HospitalBeijingChina

von Hippel-Lindau(VHL)disease is a rare autosomal dominant multiorgan disease characterized by several benign and malignant tumors rich in vascular,as well as cysts in other organs.A great clinical treatment strategy is significantly warranted for good prognosis of patients with VHL ***,we reported a case of a 45-year-old woman diagnosed with VHL disease with spinal hemangioblastoma(HB)and clear cell renal cell carcinoma(ccRCC).Four years after the resection of the right kidney,a recurrent RCC in the right kidney and a malignant lesion in the left kidney were *** patient was started on sorafenib(800 mg,daily)and tislelizumab(200 mg per 3 weeks).After 6 months of treatment,the size of renal cell carcinoma was dramatically reduced and renal function *** importantly,she achieved partial response during the whole ***,intramedullary masses resection was done and the HB in T4-5 thoracic spinal was *** symptoms such as numbness and pain were remarkably ***,tislelizumab-induced elevation in liver transaminase levels and hypothyroidism were revered by hepatoprotector and levothyroxine,*** short,comprehensive treatment strategies may benefit patients with VHL disease,especially with HB and ccRCC.

关键词： sorafenib surgery tislelizumab treatment von Hippel-Lindau disease