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Robust Correlation Clustering Problem with Locally Bounded Disagreements

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Tsinghua Science and Technology 2024年第1期29卷 66-75页

作者： Sai Ji Min li mei liang Zhenning Zhang Institute of Mathematics Hebei University of TechnologyTianjin 300401China School of Mathematics and Statistics Shandong Normal UniversityJinan 250358China College of Statistics and Data Science Beijing University of TechnologyBeijing 100124China Department of Operations Research and Information Engineering Beijing University of TechnologyBeijing 100124China

Min-max disagreements are an important generalization of the correlation clustering problem(CorCP).It can be defined as *** a marked complete graph G=(V,E),each edge in the graph is marked by a positive label"+"or a negative label"_"based on the similarity of the connected *** goal is to find a clustering C of vertices V,so as to minimize the number of disagreements at the vertex with the most ***,the disagreements are the positive cut edges and the negative non-cut edges produced by clustering *** paper considers two robust min-max disagreements:min-max disagreements with outliers and min-max disagreements with *** parameter δ∈(0,1/14),we first provide a threshold-based iterative clustering algorithm based on LP-rounding technique,which is a(1/δ,7/(1-14δ))-bi-criteria approximation algorithm for both the min-max disagreements with outliers and the min-max disagreements with outliers on one-sided complete bipartite ***,we verify that the above algorithm can achieve an approximation ratio of 21 for min-max disagreements with penalties when we set parameter δ=1/21.

关键词： min-max disagreements outliers penalties approximation algorithm LP-rounding

Regulating the crystal phase of bismuth-based semiconductors for promoted photocatalytic performance

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Science China Chemistry 2024年第6期67卷 1839-1864页

作者： Zhaohui Wu mei-Chi Chong Shiying Zhang Junshan li Yongfa Zhu Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha410022China Department of Chemistry Tsinghua UniversityBeijing100084China Institute for Advanced Study Chengdu UniversityChengdu610106China

Numerous bismuth-based semiconductors(BBSs)with sophisticated and desirable structures used as photocatalysts for efficient photocatalytic degradation of water organic contaminants have attracted considerable ***,regulating the crystal phases and phase transition of BBSs for promoted photocatalytic performance is ***,the unique crystal structure and band structure features of each typical BBSs,and the vital roles on phase controlling of each phase were systematically presented based on the classification of ***,the critical factors for the phase transition of BBSs and intrinsic driving forces endowed by phases of BBSs for enhanced photocatalytic performance of organic contaminants removal were also *** review will provide systematical guidelines and horizons for regulating the crystal phase and phase transition of BBSs,promoting photocatalytic degradation and mineralization of organic contaminants.

关键词： bismuth-based semiconductors phase regulation photocatalytic performances organic contaminants

Detecting bulk and edge exceptional points in non-Hermitian systems through generalized Petermann factors

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Frontiers of physics 2024年第2期19卷 169-177页

作者： Yue-Yu Zou Yao Zhou li-mei Chen Peng Ye School of Physics State Key Laboratory of Optoelectronic Materials and Technologiesand Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSun Yat-sen UniversityGuangzhou 510275China

Non-orthogonality in non-Hermitian quantum systems gives rise to tremendous exotic quantum phenomena,which can be fundamentally traced back to *** this paper,we introduce an interesting quantity(denoted asη)as a new variant of the Petermann factor to directly and efficiently measure non-unitarity and the associated non-Hermitian *** tuning the model parameters of underlying non-Hermitian systems,we find that the discontinuity of bothηand its first-order derivative(denoted as■η)pronouncedly captures rich physics that is fundamentally caused by *** concretely,in the 1D non-Hermitian topological systems,two mutually orthogonal edge states that are respectively localized on two boundaries become non-orthogonal in the vicinity of discontinuity ofηas a function of the model parameter,which is dubbed"edge state transition".Through theoretical analysis,we identify that the appearance of edge state transition indicates the existence of exceptional points(EPs)in topological edge *** the discontinuity of■η,we investigate a two-level non-Hermitian model and establish a connection between the points of discontinuity of■ηand EPs of bulk *** studying this connection in more general lattice models,we find that some models have discontinuity of■η,implying the existence of EPs in bulk states.

关键词： non-Hermitian Su−Schrieffer−Heeger(SSH)model exceptional point

Vanadium oxide nanospheres encapsulated in N-doped carbon nanofibers with morphology and defect dual-engineering toward advanced aqueous zinc-ion batteries

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Journal of Energy Chemistry 2024年第2期89卷 599-609,I0013页

作者： Yunfei Song Laiying Jing Rutian Wang Jiaxi Cui mei li Yunqiang Zhang School of Materials Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353ShandongChina Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina

Vanadium-based electrodes are regarded as attractive cathode materials in aqueous zinc ion batteries(ZIBs)caused by their high capacity and unique layered ***,it is extremely challenging to acquire high electrochemical performance owing to the limited electronic conductivity,sluggish ion kinetics,and severe volume expansion during the insertion/extraction process of Zn^(2+).Herein,a series of V_(2)O_(3)nanospheres embedded N-doped carbon nanofiber structures with various V_(2)O_(3)spherical morphologies(solid,core-shell,hollow)have been designed for the first time by an electrospinning technique followed thermal *** N-doped carbon nanofibers not only improve the electrical conductivity and the structural stability,but also provides encapsulating shells to prevent the vanadium dissolution and aggregation of V_(2)O_(3)***,the varied morphological structures of V_(2)O_(3)with abundant oxygen vacancies can alleviate the volume change and increase the Zn^(2+)***,the phase transition between V_(2)O_(3)and Zn_XV_(2)O_(5-m)·n H_(2)O in the cycling was also *** a result,the as-obtained composite delivers excellent long-term cycle stability and enhanced rate performance for coin cells,which is also confirmed through density functional theory(DFT)*** assembled into flexible ZIBs,the sample still exhibits superior electrochemical performance,which may afford new design concept for flexible cathode materials of ZIBs.

关键词： Aqueous zinc ion batteries Vanadium trioxide Oxygen vacancy Structure evolution Phase optimization

Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052 aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang li Qing Yu Feng-feng Chen Jia-wen He Hong-mei Yang Meng-nie li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical *** studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the *** this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%*** results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc *** ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052 aluminum alloy Al3Fe phase mechanical properties grain boundary

Enhanced photocatalytic hydrogen production from Co-MOF/CN by nitrogen and sulfur co-doped coal-based carbon quantum dots

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Journal of Rare Earths 2024年第5期42卷 838-850,I0002页

作者： Shiyong Xu mei li Yijun Wang Caiyun Gao Rongsheng Xu Zhiliang jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan750021China Ningxia Key Laboratory of Solar Chemical Conversion Technology.North Minzu University.Yinchuan 750021China State Key Laboratory of National Ethnic Affairs Commission Chemical Technology.North Minzu University Yinchuan750021China

A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots(NSCQDs)nanoparticles on the surface of sheet cobalt-based metal-organic framework(Co-MOF)and graphitic carbon nitride(g-C_(3)N_(4),CN).The structure and properties of the obtained catalysts were systematically *** effectively broaden the absorption of Co-MOF and CN in the visible *** new composite photocatalyst has high hydrogen production activity and the hydrogen production rate reaches 6254μmol/(g·h)at pH=*** the same time,NSCQDs synergy Co-MOF/CN composites have good *** four cycles of hydrogen production,the performance remains relatively *** tran sient photocurrent response and Nyquist plot experimental results further demonstrate the improvement of carrier separation efficiency in composite *** semiconductor type(n-type semico nductor)of the single-phase catalyst was determined by the Mott-Schottky test,and the band structure was *** conductive and valence bands of CN are-0.99 and 1.72 eV,respectively,and the conduction and valence bands of Co-MOF are-1.85 and 1.33 eV,*** e mechanism of the photocatalytic reaction can be inferred,that is,Z-type heterojunction is formed between CN an d Co-MOF,and NSCQDs was used as cocatalyst.

关键词： Nitrogen and sulfur co-doped Coal-based carbon quantum dots Co-MOF CN Photocatalytic hydrogen evolution Rare earths

FERONIA-mediated TIR1/AFB2 oxidation stimulates auxin signaling in Arabidopsis

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Molecular Plant 2024年第5期17卷 772-787页

作者： Baiyan Lu Shengnan Wang Hanqian Feng Jing Wang Kaixing Zhang Yilin li Ping Wu Minmin Zhang Yanshu Xia chao Peng chao li School of life Sciences East China Normal UniversityShanghai 200241China National Facilty for Protein Science Shanghai Zhangjang LabShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

The phytohormone auxin plays a pivotal role in governing plant growth and *** the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNAliNG F-BOX(TIR1/AFB)receptors function in both the nucleus and cytoplasm,the mechanism governing the distribution of TIR1/AFBs between these cellular compartments remains *** this study,we demonstrate that auxin-mediated oxidation of TIR1/AFB2 is essential for their targeting to the *** showed that small active molecules,reactive oxygen species(ROS)and nitric oxide(NO),are indispensable for the nucleo-cytoplasmic distribution of TIR1/AFB2 in trichoblasts and root *** studies revealed that this process is regulated by the FERONIA receptor kinase–NADPH oxidase signaling ***,ROS and NO initiate oxidative modifications in TIR1C140/516 and AFB2C135/511,facilitating their subsequent nuclear *** oxidized forms of TIR1C140/516 and AFB2C135/511 play a crucial role in enhancing the function of TIR1 and AFB2 in transcriptional auxin ***,our study reveals a novel mechanism by which auxin stimulates the transport of TIR1/AFB2 from the cytoplasm to the nucleus,orchestrated by the FERONIA–ROS signaling pathway.

关键词： FERONIA TIR1/AFBs oxidative modification nucleo-cytoplasmic distribution root hair development

Effects of Helicobacter pylori and Moluodan on the Wnt/β-catenin signaling pathway in mice with precancerous gastric cancer lesions

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 979-990页

作者： Yi-mei Wang Zheng-Wei Luo Yu-lin Shu Xiu Zhou lin-Qing Wang Chun-Hong liang chao-Qun Wu Chang-Ping li Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina

BACKGROUND Helicobacter pylori(***)is the primary risk factor for gastric cancer(GC),the Wnt/β-Catenin signaling pathway is closely linked to *** has a high mortality rate and treatment cost,and there are no drugs to prevent the progression of gastric precancerous lesions to ***,it is necessary to find a novel drug that is inexpensive and preventive to against *** To explore the effects of *** and Moluodan on the Wnt/β-Catenin signaling pathway and precancerous lesions of GC(PLGC).METHODS Mice were divided into the control,N-methyl-N-nitrosourea(MNU),***+MNU,and Moluodan *** first created an *** infection model in the ***+MNU and Moluodan groups.A PLGC model was created in the remaining three groups except for the control *** was fed to mice in the Moloudan group ad *** general condition of mice were observed during the whole experiment *** tissues of mice were grossly and microscopically *** quantitative real-time PCR(qRT-PCR)and Western blotting analysis,the expression of relevant genes were *** Mice in the ***+MNU group showed the worst performance in general condition,gastric tissue visual and microscopic observation,followed by the MNU group,Moluodan group and the control ***-PCR and Western blotting analysis were used to detect the expression of relevant genes,the results showed that the ***+MNU group had the highest expression,followed by the MNU group,Moluodan group and the control *** *** can activate the Wnt/β-catenin signaling pathway,thereby facilitating the development and progression of *** suppressed the activation of the Wnt/β-catenin signaling pathway,thereby decreasing the progression of PLGC.

关键词： Helicobacter pylori Gastric cancer Wnt/β-catenin signaling pathway Moluodan

Thermal runaway evolution of a 280 Ah lithium-ion battery with liFePO_(4) as the cathode for different heat transfer modes constructed by mechanical abuse

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Journal of Energy Chemistry 2024年第6期93卷 32-45,I0002页

作者： Zhixiang Cheng Chengdong Wang Wenxin mei Peng Qin Junyuan li Qingsong Wang State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026AnhuiChina

lithium iron phosphate batteries have been increasingly utilized in recent years because their higher safety performance can improve the increasing trend of recurring thermal runaway ***,the safety performance and mechanism of high-capacity lithium iron phosphate batteries under internal short-circuit challenges remain to be *** work analyzes the thermal runaway evolution of high-capacity liFePO_(4) batteries under different internal heat transfer modes,which are controlled by different penetration *** penetration cases involving complete penetration and incomplete penetration were detected during the test,and two modes were performed incorporating nails that either remained or were removed after penetration to comprehensively reveal the thermal runaway mechanism.A theoretical model of microcircuits and internal heat conduction is also *** results indicated three thermal runaway evolution processes for high-capacity batteries,which corresponded to the experimental results of thermal equilibrium,single thermal runaway,and two thermal runaway *** difference in heat distribution in the three phenomena is determined based on the microstructure and material structure near the *** controlling the heat dissipation conditions,the time interval between two thermal runaway events can be delayed from 558 to 1417 s,accompanied by a decrease in the concentration of in-situ gas production during the second thermal runaway event.

关键词： lithium-ion battery safety Micro short-circuit cell Heat transfer modes Internal short circuit Nail-penetration test