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A polynomial resultant approach to algebraic constructions of extremal graphs

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Science China Mathematics 2025年第2期68卷 485-506页

作者： Tao Zhang Zixiang Xu gennian ge Institute of Mathematics and Interdisciplinary Sciences Xidian UniversityXi’an 710071China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

The Turán problem asks for the largest number of edges ex(n,H)in an n-vertex graph not containing a fixed forbidden subgraph H,which is one of the most important problems in extremal graph ***,the order of magnitude of ex(n,H)for bipartite graphs is known only in a handful of *** particular,giving explicit constructions of extremal graphs is very challenging in this *** this paper,we develop a polynomial resultant approach to the algebraic construction of explicit extremal graphs,which can efficiently decide whether a specified structure exists.A key insight in our approach is the multipolynomial resultant,which is a fundamental tool of computational algebraic *** main results include the matched lower bounds on the Turán number of 1-subdivision of K3,t1and the linear Turán number of the Berge theta hypergraph■_(3,t_(2))^(B).where t_(1)=25 and t_(2)=***,the constant t1improves the random algebraic construction of Bukh and Conlon(2018)and makes the known estimation better on the smallest value of t1concerning a problem posed by Conlon et al.(2021)by reducing the value from a magnitude of 10^(56)to the number 25,while the constant t_(2)improves a result of He and Tait(2019).

关键词： Turan number resultant algebraic construction subdivision Berge theta hypergraph

Pyrroloquinoline quinone:a potential neuroprotective compound for neurodegenerative diseases targeting metabolism

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Neural Regeneration Research 2025年第1期20卷 41-53页

作者： Alessio Canovai Pete A.williams Department of Biology University of PisaPisaItaly Department of Clinical Neuroscience Division of Eye and VisionSt.Erik Eye HospitalKarolinska InstitutetStockholmSweden

Pyrroloquinoline quinone is a quinone described as a cofactor for many bacterial dehydrogenases and is reported to exert an effect on metabolism in mammalian cells/*** quinone is present in the diet being available in foodstuffs,conferring the potential of this compound to be supplemented by dietary *** quinone’s nutritional role in mammalian health is supported by the extensive deficits in reproduction,growth,and immunity resulting from the dietary absence of pyrroloquinoline quinone,and as such,pyrroloquinoline quinone has been considered as a“new vitamin.”Although the classification of pyrroloquinoline quinone as a vitamin needs to be properly established,the wide range of benefits for health provided has been reported in many *** this respect,pyrroloquinoline quinone seems to be particularly involved in regulating cell signaling pathways that promote metabolic and mitochondrial processes in many experimental contexts,thus dictating the rationale to consider pyrroloquinoline quinone as a vital compound for mammalian *** the regulation of different metabolic mechanisms,pyrroloquinoline quinone may improve clinical deficits where dysfunctional metabolism and mitochondrial activity contribute to induce cell damage and *** quinone has been demonstrated to have neuroprotective properties in different experimental models of neurodegeneration,although the link between pyrroloquinoline quinone-promoted metabolism and improved neuronal viability in some of such contexts is still to be fully ***,we review the general properties of pyrroloquinoline quinone and its capacity to modulate metabolic and mitochondrial mechanisms in physiological *** addition,we analyze the neuroprotective properties of pyrroloquinoline quinone in different neurodegenerative conditions and consider future perspectives for pyrroloquinoline quinone’s potential in health and disease.

关键词： metabolism mitochondria neurodegenerative disease neuroprotection pyrroloquinoline quinone retinal diseases

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A fast amplitude preserving three-parameter 3D parabolic Radon transform and its application on multiple attenuation

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Petroleum Science 2025年第1期22卷 163-177页

作者： Ji-Tao Ma Kai-ge Zhao Zhen Liao College of geophysics China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and engineering China University of Petroleum (Beijing) CNPC Key Laboratory of geophysical Prospecting China University of Petroleum (Beijing)

Seismic wavefields propagate through three-dimensional(3D) space, and their precise characterization is crucial for understanding subsurface structures. Traditional 2D algorithms, due to their limitations, are insufficient to fully represent three-dimensional wavefields. The classic 3D Radon transform algorithm assumes that the wavefield's propagation characteristics are consistent in all directions, which often does not hold true in complex underground media. To address this issue, we present an improved 3D threeparameter Radon algorithm that considers the wavefield variation with azimuth and provides a more accurate wavefield description. However, introducing new parameters to describe the azimuthal variation also poses computational challenges. The new Radon transform operator involves five variables and cannot be simply decomposed into small matrices for efficient computation; instead, it requires large matrix multiplication and inversion operations, significantly increasing the computational load. To overcome this challenge, we have integrated the curvature and frequency parameters, simplifying all frequency operators to the same, thereby significantly improving computation efficiency. Furthermore,existing transform algorithms neglect the lateral variation of seismic amplitudes, leading to discrepancies between the estimated multiples and those in the data. To enhance the amplitude preservation of the algorithm, we employ orthogonal polynomial fitting to capture the amplitude spatial variation in 3D seismic data. Combining these improvements, we propose a fast, amplitude-preserving, 3D threeparameter Radon transform algorithm. This algorithm not only enhances computational efficiency while maintaining the original wavefield characteristics, but also improves the representation of seismic data by increasing amplitude fidelity. We validated the algorithm in multiple attenuation using both synthetic and real seismic data. The results demonstrate that the new algor

关键词： Three-parameter 3D Radon Orthogonal polynomial Amplitude-preserving Multiple attenuation

The influence mechanism of environmental factors on DGT adsorbing sulfonamides and the migration between water and sediment

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Journal of environmental Sciences 2025年第5期151卷 347-359页

作者： Peng Zhang Jingfeng Yan Hao Ji Linke ge Yanying Li School of environmental Science and Technology Shaanxi University of Science&TechnologyXi’an 710021China College of environmental Sciences and engineering Dalian Maritime UniversityDalian 116026China

Obtaining the sulfonamides(SAs)concentrations in the water body and sediment bulk was a prerequisite to reveal their transport and partitioning behavior in sediment-water environments and accurately assess their ecological *** the present study,the influences of multifactor interactions on the performance of o-DGTs with XAD-18 binding gels were analyzed by central combination experiments and response surfaces analysis,in which the target compounds were 9 *** results indicated that dissolved organic matter(DOM),pH,and suspended particulate matter(SS)had significant effects on the o-DGT sampling,whereas this o-DGT was independent of the ionic strength(IS).Concentning the composite influence of the four factors,the interaction between DOM and SS posed the most significant effect on all 9 SAs ***,an o-DGT and DIFSmodel was applied to explore the SAs migration between the water-sediments *** difference between desorption rate(k_(b))and adsorption rates(k_(f))values suggested that the kinetics of SAs was dominated by ***,the short-term sediment-water partitioning of SAs was clarified on the basis of distribution coefficient(K_(dl))for the labile SAs,among which the sulfadiazine(SDZ)had the largest labile *** ability of sediments to release SAs to the liquid phase as a sink was determined by response time(T_(c)).Among the 9 SAs,the longterm release of soseulfamethoxypyridazine(SMP)from the solid phase of sediments would have a potential risk to the aquatic environment,to which more attention should be paid in the future.

关键词： Sulfonamides O-DGT Water-sediments interface DIFS Distribution

escort: a system for rapid and long-term tracking of multiple insect objects

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Insect Science 2025年第1期32卷 356-362页

作者： Chengshi Wu Jin ge Bin Han Hengjing Lan Xian Zhou Zhuxi ge Weichan Cui Xiaofeng Liu Xianhui Wang College of AI and Automation Hohai UniversityChangzhouJiangsu ProvinceChina State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina CAS Centre for excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

Dear editor,Accurately tracking multiple individuals in insect groups provides crucial information for insect collective behavior,population activity and interactions with the environment(Price et al.,201l).

关键词： collective ). multiple

Magnetically-responsive phase change thermal storage materials:Mechanisms,advances,and beyond

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Journal of energy Chemistry 2025年第2期101卷 485-510页

作者： Yan Gao Yang Li Jinjie Lin Panpan Liu Xiao Chen ge Wang Beijing Advanced Innovation Center for Materials genome engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing School of Physics and Astronomy Beijing Normal University Shunde Graduate School University of Science and Technology Beijing

Rapid advances in thermal management technology and the increasing need for multi-energy conversion have placed stringent energy efficiency requirements on next-generation shape-stable composite phase change materials(PCMs).Magnetically-responsive phase change thermal storage materials are considered an emerging concept for energy storage systems,enabling PCMs to perform unprecedented functions(such as green energy utilization,magnetic thermotherapy,drug release,etc.).The combination of multifunctional magnetic nanomaterials and PCMs is a milestone in the creation of advanced multifunctional composite ***,a timely and comprehensive review of composite PCMs based on magnetic nanoparticle modification is still ***,we furnish an exhaustive exposition elucidating the cutting-edge advancements in magnetically responsive composite *** delve deeply into the multifarious roles assumed by distinct nanoparticles within composite PCMs of varying dimensions,meticulously scrutinizing the intricate interplay between their architectures and thermophysical ***,we prognosticate future research trajectories,delineate alternative stratagems,and illuminate prospective *** review is intended to stimulate broader academic interest in interdisciplinary fields and provide valuable insights into the development of next-generation magnetically-responsive composite PCMs.

关键词： Magnetic nanoparticles Magnetic-thermal conversion Phase change materials Response mechanism Thermal energy storage

Study on the Radiation Synthesis Mechanism and the electrochemical Property of Polyaniline

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Chinese Journal of Polymer Science 2025年第2期43卷 328-340页

作者： Shuo Yan Zi-Fang Guo Zhi-Qing ge Bao-Ying Zhang Ya-Ru Zhang Yi-Shao Li Mo-Zhen Wang Xue-Wu ge State Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei230026China

As a highly promising conductive polymer material,the synthesis method,structure regulation,and performance improvement of polyaniline(PANI)are hot research *** this work,the radiation-induced polymerization of aniline in HNO_(3)solution was successfully achieved at room temperature without the use of chemical *** the analysis of the radiation chemical reactions of inorganic acids and nitrate salt solutions,the characterization of the intermediate free radicals in the irradiated systems,and the influence of the pH of the solutions on the polymerization activity and product morphologies,the radiation-induced polymerization mechanism of aniline is discussed in detail and *** at a condition of[HNO_(3)]>[aniline],i.e.,pHe successfully obtained underγ-ray *** polymerization begins with the oxidation of aniline cations to aniline cation radicals by·NO_(3)generated by radiolysis reactions,and undergoes repeated three steps of monomer free radical recombination,deprotonation,and oxidation reaction of·NO_(3),thus forming a PANI *** addition to the polymerization reaction,the aniline units are protonated and oxidized because of the strongly acidity and oxidation of the reaction system under γ-ray irradiation,which means that the molecular chain structure of the radiation-synthesized PANI can be regulated by pH,nitrate concentration,and irradiation ***-synthesized PANI has a moderate protonation and oxidation state,which can be used for the preparation of PANI supercapacitors with better electrochemical properties than those prepared by chemical oxidation under the same *** work presents a new radiation-synthesis method and polymerization mechanism of PANI,which not only expands the application of radiation technique in the field of polymer synthesis,but also provides a new idea for the structural regulation and electrochemical property optimization of PANI.

关键词： Aniline Radiation-induced polymerization Polyaniline electrochemical property

Interfacial B-O bonding modulated S-scheme B-doped N-deficient C_(3)N_(4)/O-doped-C_(3)N_(5) for efficient photocatalytic overall water splitting

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Chinese Chemical Letters 2025年第1期36卷 355-361页

作者： entian Cui Yulian Lu Zhaoxia Li Zhilei Chen Chengyan ge Jizhou Jiang Key Laboratory for Advanced Technology in environmental Protection of Jiangsu Province Yancheng Institute of TechnologyYancheng 224051China School of environmental ecology and Biological engineering Key Laboratory of Green Chemical Engineering Process of Ministry of EducationEngineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationWuhan Institute of TechnologyWuhan 430205China

Photocatalytic overall pure water splitting is a promising method for generating green hydrogen energy under mild ***,this process is often hindered by sluggish electron-hole separation and *** address this,a step-scheme(S-scheme)B-doped N-deficient C_(3)N_(4)/O-doped C_(3)N_(5)(BN-C_(3)N_(4)/O-C_(3)N_(5))heterojunction with interfacial B-O bonds has been *** Pt and Co(OH)_(2) as co-catalysts,BN-C_(3)N_(4)/O-C_(3)N_(5) S-scheme heterojunction demonstrates significantly enhanced photocatalytic activity for overall pure water splitting under visible light,achieving H_(2) and O_(2) evolution rates of 40.12 and 19.62μmol/h,*** characterizations and experiments revealed the performance-enhancing effects of the enhanced built-in electric field and the interfacial B-O ***,the strengthened built-in electric field provides sufficient force for rapid interfacial electron ***,by reducing the transport energy barrier and transfer distance,the interfacial B-O bonds facilitate rapid recombination of electrons and holes with relatively low redox potential via the S-scheme charge-transfer route,leaving the high-potential electrons and holes available for H^(+)reduction and OH^(-)oxidation ***,the photocatalytic efficiency of BN-C_(3)N_(4)/O-C_(3)N_(5) S-scheme heterojunction was significantly improved,making it a promising approach for green hydrogen production through overall pure water splitting.

关键词： Interfacial B-O bonds BN-C_(3)N_(4) O-C_(3)N_(5) S-scheme heterojunction Water splitting

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Synergistically S/N self-doped biochar as a green bifunctional cathode catalyst in electrochemical degradation of organic pollutant

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Green energy & environment 2025年第1期10卷 214-230页

作者： Xuechun Wang Huizhong Wu Jiana Jing ge Song Xuyang Zhang Minghua Zhou Raf Dewil Key Laboratory of Pollution Process and environmental Criteria Ministry of EducationCollege of Environmental Science and EngineeringNankai UniversityTianjin300350China Tianjin Key Laboratory of environmental Technology for Complex Trans-Media Pollution Nankai UniversityTianjin300350China Tianjin Advanced Water Treatment Technology International Joint Research Center College of Environmental Science and EngineeringNankai UniversityTianjin300350China Department of Chemical engineering KU LeuvenJ.De Nayerlaan 5Sint-Katelijne-Waver B2860Belgium

Biomass-derived heteroatom self-doped cathode catalysts has attracted considerable interest for electrochemical advanced oxidation processes(eAOPs)due to its high performance and sustainable ***,we illustrated the morphological fates of waste leaf-derived graphitic carbon(WLGC)produced from waste ginkgo leaves via pyrolysis temperature regulation and used as bifunctional cathode catalyst for simultaneous H_(2)O_(2) electrochemical generation and organic pollutant degradation,discovering S/N-self-doping shown to facilitate a synergistic effect on reactive oxygen species(ROS)*** the optimum temperature of 800℃,the WLGC exhibited a H_(2)O_(2) selectivity of 94.2%and tetracycline removal of 99.3%within 60 *** functional theory calculations and in-situ Fourier transformed infrared spectroscopy verified that graphitic N was the critical site for H_(2)O_(2) *** pyridinic N and thiophene S were the main active sites responsible for OH generation,N vacancies were the active sites to produce ^(1)O_(2) from O_(2).The performance of the novel cathode for tetracycline degradation remains well under a wide pH range(3–11),maintaining excellent stability in 10 *** is also industrially applicable,achieving satisfactory performance treating in real water *** system facilitates both radical and non-radical degradation,offering valuable advances in the preparation of cost-effective and sustainable electrocatalysts and hold strong potentials in metal-free eAOPs for organic pollutant degradation.

关键词： Biochar S and N self-doping H_(2)O_(2)production In-situ FTIR Metal-free electrochemical advanced oxidation processes

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