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Irreducible representations of GL_(n)(C)of Minimal Gelfand-Kirillov dimension

Acta Mathematica Sinica,English Series 2024年第3期40卷 639-657页

作者： Zhan Qiang BAI Yang Yang CHEN dong Wen LIU Bin Yong SUN School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China School of Sciences JiangnanUniversityWui214122P.R.China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058P.R.China Institute for Advanced Study in Mathematics Zhejiang UniversityHangzhou 310058P.R.China

In this article,by studying the Bernstein degrees and Goldie rank polynomials,we es-tablish a comparison between the irreducible representations of G=GL_(n)(C)possessing the minimal Gelfand-Kirillov dimension and those induced from finite-dimensional representations of the maximal parabolic subgroup of G of type(n-1,1).We give the transition matrix between the two bases for the corresponding coherent families.

关键词： Bernstein degree coherent continuation Gelfand-Kirillov dimension

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Exploring precursor effect in in-situ reconstruction of Bi metal organic-frameworks during CO_(2)electroreduction reaction to tailor formate selectivity towards 100%

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Science china Chemistry 2024年第7期67卷 2190-2198页

作者： Zhida Liu Qikui Fan Hang Huo Fanglei Yao Xiaoping Gao Jin Wang College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Functional Molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Bi-based metal-organic frameworks(Bi-MOFs)as efficient catalysts for the CO_(2)electroreduction reaction(Crr)have been extensively *** has been established that Bi-MOFs usually undergo in-situ transformation during the Crr,ultimately converting into Bi ***,the effect of the MOF precursors on the structure of the derived Bi catalysts and consequently on their electrocatalytic properties has not been clearly *** this work,we prepared four variants of a novel Bi-MOF with different morphologies and dimensions,and explored the effects of the precursors on the resulting Bi catalysts and their Crr performance.A precursor-dependent in-situ transformation and its profound impact on tuning the CO_(2)-formate FE towards~100%have been *** the four examined variants,Bi-MOF with nanocube-like morphology(BiMOF-NC)is transformed into thin and flat Bi nanosheets capable of successfully enveloping the fibers of carbon paper(working electrode),while the other three variants with increased size and dodecahedral/octahedral geometry have been transformed into Bi nanoflowers,exposing a fair portion of the carbon fibers in the working ***,the transformation rate was found to be dependent on the precursors and BiMOF-NC exhibited the highest rate of reconstruction compared with other ***,the Bi catalyst derived from BiMOF-NC delivered a selectivity for the formate product of nearly 100%at-1.2 V(*** hydrogen electrode(rHE))and of over 95%in a wide potential range due to efficient suppression of the competing hydrogen evolution reaction(HEr)over carbon *** in-situ transformed BiMOFNC also demonstrated equivalently high formate selectivity at large current densities(≥100 mA cm^(-2))in flow cell reactors as that in H-type reactors,underscoring its potential for industrial *** work highlights the necessity of finely tuning the structural features of MOF precursors to achieve optim

关键词： Bi-MOFs precursor effect in-situ transformation Bi nanosheets CO_(2)-to-formate

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Electrochemical reduction of carbon dioxide to produce formic acid coupled with oxidative conversion of biomass

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Journal of Energy Chemistry 2024年第5期92卷 705-729页

作者： Xi Liu Yifan Wang Zhiwei dai daihong Gao Xuebing Zhao Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Institute of Applied Chemistry Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Electrochemical reduction of CO_(2)(CO_(2)rr)has become a research hot spot in recent years in the context of carbon *** is one of the most promising products obtained by electrochemical reduction of CO_(2) due to its high energy value as estimated by market price per energy unit and wide application in chemical *** is the most abundant renewable resource in the natural *** biomass oxidative conversion with CO_(2)rr driven by renewable electricity would well achieve carbon *** this work,we comprehensively reviewed the current research progress on CO_(2)rr to produce HCOOH and coupled system for conversion of biomass and its derivatives to produce value-added ***-and Bi-based electrocatalysts are discussed for CO_(2)rr with regards to the structure of the catalyst and reaction ***-oxidation reactions of biomass derived sugars,alcohols,furan aldehydes and even polymeric components of lignocellulose were reviewed as alternatives to replace oxygen evolution reaction(OEr)in the conventional electrolysis *** was recommended that to further improve the efficiency of the coupled system,future work should be focused on the development of more efficient and stable catalysts,careful design of the electrolytic cells for improving the mass transfer and development of environment-friendly processes for recovering the formed formate and biomass oxidation products.

关键词： Electrochemical reduction of CO_(2) Formic acid Oxidative conversion of biomass Lignocellulose Coupled system

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deuterium distribution and behavior of blisters in pre-damaged and undamaged tungsten

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Tungsten 2024年第3期6卷 647-656页

作者： Cong Li Xiao-Wa Wang ran-ran Su Xuan-Xin Hu Shu-Guang Wei Han-Jun Tu Li-Qun Shi Hong-Liang Zhang Key Laboratory of Nuclear Physics and Ion-Beam Application Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Materials Science and Engineering University of WisconsinMadison WI 53706USA

Tungsten(W),as a plasma-facing material,is subjected to high fluence plasma,resulting in both radiation damage and deuterium(d)*** study explores the blistering behavior and d supersaturated layers in both pre-damaged and undamaged W *** achieve a uniform damage profile similar to neutron irradiation,carbon(C)ions with multiple energies and angles were *** samples were further irradiated with low-energy d ions under two fluences at temperatures from~380 to 640 *** various experimental techniques,we found that pre-damaged W samples can effectively suppress the formation of blistering and lower the threshold temperature at which the surface remains free of *** also observed the prominent d supersaturated peaks within the depth of 20 nm in both pre-damaged and undamaged ***,a close correlation between blistering and the d supersaturation was *** results suggest that neutron irradiation in the fusion reactors could increase the critical d concentration for blistering,while a greater depth of damage facilitated the inward diffusion of d,thereby reducing the d concentration gradient and alleviating surface blistering.

关键词： Tungsten deuterium Supersaturated layer Blister Ion irradiation Pre-damage

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LKPNr: Large Language Models and Knowledge Graph for Personalized News recommendation Framework

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Computers, Materials & Continua 2024年第6期79卷 4283-4296页

作者： Hao Chen runfeng Xie Xiangyang Cui Zhou Yan Xin Wang Zhanwei Xuan Kai Zhang State Key Laboratory of Communication Content Cognition People’s Daily OnlineBeijing100733China

Accurately recommending candidate news to users is a basic challenge of personalized news recommendation *** methods are usually difficult to learn and acquire complex semantic information in news texts,resulting in unsatisfactory recommendation ***,these traditional methods are more friendly to active users with rich historical ***,they can not effectively solve the long tail problem of inactive *** address these issues,this research presents a novel general framework that combines Large Language Models(LLM)and Knowledge Graphs(KG)into traditional *** learn the contextual information of news text,we use LLMs’powerful text understanding ability to generate news representations with rich semantic information,and then,the generated news representations are used to enhance the news encoding in traditional *** addition,multi-hops relationship of news entities is mined and the structural information of news is encoded using KG,thus alleviating the challenge of long-tail *** results demonstrate that compared with various traditional models,on evaluation indicators such as AUC,Mrr,ndCG@5 and ndCG@10,the framework significantly improves the recommendation *** successful integration of LLM and KG in our framework has established a feasible way for achieving more accurate personalized news *** code is available at https://***/Xuan-ZW/LKPNr.

关键词： Large language models news recommendation knowledge graphs(KG)

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A Te-based memristor with short-term depression behavior

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JOUrNAL OF PHYSICS d-APPLIEd PHYSICS 2025年第17期58卷 175101-175101页

作者： dong, dongli duan, Wenrui Wang, Xinxin Li, Huanglong Beijing Informat Sci & Technol Univ Coll Instrument Sci & Optoelect Engn Beijing 100101 Peoples R China Tsinghua Univ Ctr Brain Inspired Comp Res Dept Precis Instrument Beijing 100084 Peoples R China Chinese Inst Brain Res Beijing 102206 Peoples R China

Short-term depression (STd) is a critical component of neuronal plasticity. However, the emulation of STd in the emerging memristive neuromorphic devices remains challenging because memristors are almost invariably set-first and, if volatile, typically exhibit volatile set behavior. Although these characteristics are essential for emulating short-term facilitation (STf), they contradict the requirements for emulating STd. In this work, we experimentally demonstrate a Te-based memristor with reset-first behavior as well as volatile reset switching characteristic. These unusual phenomena are connected to the fabrication-induced Te intermixing in the originally insulating interlayer and the unique thermo-electric behavior of Te in response to electrical stimuli. With these properties, the Te-based memristor can naturally emulate neuronal STd, in contrast to Ag-based memristors which behave like STf synapses. This work advances the use of Te for neuromorphic computing and extends the functionalities of memristors.

关键词： neuromorphic computing short-term depression tellurium reset-first volatile reset

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Effect of Proppant on Seepage and Heat Transfer Characteristics in Fractured Granite of Hot dry rock Geothermal Systems

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ENErGY SCIENCE & ENGINEErING 2025年第2期13卷 847-861页

作者： dong, Xu Wu, Yu Li, decheng Hao, Yang Geng, Haozhe China Univ Min & Technol State Key Lab Intelligent Construct & Hlth Operat Xuzhou Jiangsu Peoples R China

The seepage and heat transfer characteristics of fractured rock are critical issues in hot dry rock exploitation. This paper investigates the effects of proppant on the seepage characteristics under different conditions through seepage experiments on split granite fractures. Subsequently, seepage-heat transfer coupling mechanisms in fractured granite are elucidated through numerical simulations. The results indicate that the flow rate increases in fractures with large crack widths as temperature rises, while in fractures with small crack widths, an increase in temperature reduces the flow rate. Additionally, normal constraint force increases with rising confining pressure, consequently reducing the flow rate. Extension of seepage paths is favored by higher injection pressures, thereby improving flow rates. The inclusion of proppant effectively supports the fracture, expanding its width and significantly increasing the flow rate. Furthermore, injection into the reservoir forms a low-temperature cooling zone, which gradually advances towards the outlet over time. Initially, the outlet temperature and extract heat rate remain stable before decreasing almost linearly. Proppant filling accelerates the heat transfer rate and significantly boosts the initial extract heat rate;however, it also leads to a faster decline in reservoir heat quantity, resulting in a subsequent extract heat rate lower than that of unfilled fractures. These findings underscore the importance of balanced extract heat efficiency and enhanced geothermal system reservoir longevity for the sustained exploitation of geothermal energy.

关键词： fractured granite heat transfer proppant seepage

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Effective removal of Sb(V)from aqueous solutions by micro-electrolysis with composite scrap iron-manganese as filler

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 516-524页

作者： Shangkun dING Saihua HUANG Yiping ZHANG Yongchao ZHOU Institute of Municipal Engineering Zhejiang UniversityHangzhou310058China Zhejiang University of Water Resources and Electric Power Hangzhou310018China

Micro-electrolysis(ME)technology is investigated for improving the efficiency of removal of pentavalent antimony(Sb(V))from the *** this study,an ME system composed of scrap iron filings,waste manganese fillings,and activated carbon(Fe-Mn-C ME)was used to efficiently remove Sb(V).The results proved that,compared with conventional iron-carbon micro-electrolysis(Fe-C ME),Fe-Mn-C ME significantly enhances the removal rate of Sb(V)when the hydraulic retention time is 10–24 *** Fe-Mn flocs produced by this system were analyzed using X-ray diffraction(Xrd),energy-dispersive X-ray spectroscopy(EdS),X-ray photoelectron spectroscopy(XPS),and Brunauer-Emmett-Teller(BET)surface area analysis,which revealed that the flocs were mostly Mn-substituted FeOOH and had a relatively larger specific surface area,providing better adsorption ***,it was found that the removal rate of Sb(V)decreased as the iron-carbon mass ratio increased,while it first increased and then decreased as the manganese content *** reduction of Fe(III)was accelerated with an increase in the addition of manganese,leading to an increase in the concentration of Fe(II).The electron transfer and the formation of Fe(II)were facilitated by the potential difference between manganese and carbon,as well as by the formation of microcells between iron and manganese,which improved the reduction ability of Sb(V).From our thorough investigation and research,this is the first report that has proposed Fe-Mn-C ME for removing *** provides a novel approach and technological support for removing Sb(V)efficiently.

关键词： Antimony Iron Manganese Micro-electrolysis(ME) Electrochemistry Mechanism

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Three-dimensional parametric contact analysis of planetary roller screw mechanism and its application in grouping for selective assembly

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Frontiers of Mechanical Engineering 2024年第1期19卷 53-72页

作者： Huilin HE Peitang WEI Huaiju LIU Xuesong dU rui HU Genshen LIU Yajun WU State Key Laboratory of Mechanical Transmission for Advanced Equipment Chongqing UniversityChongqing 400044China Taiyuan Heavy Machinery Group Co. Ltd.Taiyuan 030024China

The planetary roller screw mechanism(PrSM)is a novel precision transmission mechanism that realizes the conversion between linear and rotary *** contact characteristics of helical surfaces directly determine PrSM’s performance in load-carrying capacity and transmission ***,studying the contact characteristics of PrSM forms the fundamental basis for enhancing its transmission *** this study,a three-dimensional parametric analysis method of contact characteristics is proposed based on the PrSM meshing principle and PyVista(a high-level API to the Visualization Toolkit).The proposed method considers the influence of machining errors among various thread *** effects of key machining errors on contact positions and axial clearance,as well as their sensitivities,are *** excellent solution accuracy,this method exhibits higher calculation efficiency and stronger robustness than the analytical and numerical meshing *** influence of nominal diameter and pitch errors of the screw,roller,and nut on the axial clearance follows a linear relationship,whereas flank angle errors have negligible effects on the axial *** corresponding influence coefficients for these three machining errors on the axial clearance are 0.623,0.341,and *** variations in contact positions caused by individual errors are *** angle errors and roller diameter errors result in linear displacements of the contact points,whereas pitch errors cause the contact points to move along the arc of the roller *** on the proposed threedimensional parametric contact characteristics analysis method,the Fuzzy C-Means clustering algorithm considering error sensitivity is utilized to establish a component grouping technique in the selective assembly of critical PrSM components,ensuring the rational and consistent clearances based on the given component’s machining *** study provides effective guidance for analyzing conta

关键词： planetary roller screw mechanism(PrSM) contact position axial clearance machining error grouping for selective assembly

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An Imaging Method for Marine Targets in Corner reflector Jamming Scenario Based on Time-Frequency Analysis and Modified Clean Technique

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rEMOTE SENSING 2025年第2期17卷 310-310页

作者： Chen, Changhong Liu, Wenkang Gao, Yuexin Cui, Lei Chen, Quan Fu, Jixiang Xing, Mengdao Xidian Univ Natl Key Lab Radar Signal Proc Xian 710071 Peoples R China Xidian Univ Acad Adv Interdisciplinary Res Xian 710071 Peoples R China Xidian Univ Sch Aerosp Sci & Technol Xian 710071 Peoples R China Shanghai Inst Satellite Engn Shanghai 201109 Peoples R China

In the corner reflector jamming scenario, the ship target and the corner reflector array have different degrees of defocusing in the synthetic aperture radar (SAr) image due to their complex motions, which is unfavorable to the subsequent target recognition. In this manuscript, we propose an imaging method for marine targets based on time-frequency analysis with the modified Clean technique. Firstly, the motion models of the ship target and the corner reflector array are established, and the characteristics of their doppler parameter distribution are analyzed. Then, the Chirp rate-Quadratic Chirp rate distribution (Cr-QCrd) algorithm is utilized to estimate the doppler parameters. To address the challenges posed by the aggregated scattering points of the ship target and the overlapping doppler histories of the corner reflector array, the Clean technique is modified by short-time Fourier transform (STFT) filtering and amplitude-phase distortion correction using fractional Fourier transform (FrFT) filtering. This modification aims to improve the accuracy and efficiency of extracting scattering point components. Thirdly, in response to the poor universality of the traditional Clean iterative termination condition, the kurtosis of the residual signal spectrum amplitude is adopted as the new iterative termination condition. Compared with the existing imaging methods, the proposed method can adapt to the different doppler distribution characteristics of the ship target and the corner reflector array, thus realizing better robustness in obtaining a well-focused target image. Finally, simulation experiments verify the effectiveness of the algorithm.

关键词： marine target corner reflector ship ISAr imaging doppler parameter estimation Clean technique

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