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基于Pair Copula的多风电场风险约束随机经济调度 被引量:1
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作者 韦洪波 阮诗迪 +3 位作者 张雄宝 郑志豪 韦昌福 刘欣然 《电测与仪表》 北大核心 2025年第7期165-173,共9页
近年来,风电并网政策的落实,以及风电渗透率的增加为节能减排起到了积极作用,但由于风电出力具有明显的不确定性和相关性,使得电力系统经济调度也面临巨大挑战。文章提出一种刻画风电场相关性的Pair Copula方法,基于准蒙特卡罗模拟法生... 近年来,风电并网政策的落实,以及风电渗透率的增加为节能减排起到了积极作用,但由于风电出力具有明显的不确定性和相关性,使得电力系统经济调度也面临巨大挑战。文章提出一种刻画风电场相关性的Pair Copula方法,基于准蒙特卡罗模拟法生成大量风电出力的随机场景,以表征多个相关风电场出力的不确定性。为解决含风电出力的电网随机经济调度问题,构建考虑风险约束的均值-方差模型,所建均方差模型同时涵盖了考虑风电出力不确定性下的经济成本和经济风险,其中经济风险通过燃料成本的最小方差计算得到。为更适应实际调度现状,文章建立燃油成本概率密度函数,并提出预定义的置信区间对所建均方差模型进行改进。通过对改进的IEEE 30节点系统进行算例仿真,验证了所提Pair Copula方法和均值-方差模型的有效性。 展开更多
关键词 pair Copula 随机经济调度 经济风险 准蒙特卡罗 改进的均值-方差模型
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Selenate-based heterojunction with cobalt-nickel paired site for electrocatalytic oxidation of 5-hydroxymethylfurfural coupling water splitting to produce hydrogen 被引量:1
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作者 Zhengru Yang Jia Hui +4 位作者 Wangxi Fan Pengcheng Liu Chunyong Zhang Shuang Dong Zhou Yang 《Journal of Energy Chemistry》 2025年第2期156-162,I0005,共8页
It is very appealing that 5-hydroxymethylfurfural(HMF)is electrocatalytical oxidized as 2,5-furandicarboxylic acid(FDCA)linking to non-classical cathodic hydrogen(H_(2))production.However,the electrocatalysts for elec... It is very appealing that 5-hydroxymethylfurfural(HMF)is electrocatalytical oxidized as 2,5-furandicarboxylic acid(FDCA)linking to non-classical cathodic hydrogen(H_(2))production.However,the electrocatalysts for electrocatalytic HMF oxidative reaction(e-HMFOR)have been facing low Faradaic efficiency(FE)and high water splitting voltage.Herein,we propose a strategy of the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction by constructing a Co-Ni paired site,where the Co site is in charge of adsorbing for HMF while the electrons are transferred to the Ni site,thus giving the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction superior electrocata lytic performances for e-HMFOR and water splitting.By optimizing conditions,the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction has high conversion of 99.7%,high selectivity of 99.9%,and high FE of 98.4%at 1.3 V,as well as low cell voltage of 1.31 V at 10 mA cm^(-2)in 1 M KOH+0.1 M HMF.This study offers a potential insight for e-HMFOR to high value-added FDCA coupling water splitting to produce H_(2)in an economical manner. 展开更多
关键词 e-HMFOR FDCA Co-Ni paired site HETEROJUNCTION Hydrogen evolution
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Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
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作者 Shi Li Didi Sun 《Computers, Materials & Continua》 SCIE EI 2025年第1期1069-1086,共18页
With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions... With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying reasons.This comprehension is crucial for making informed strategic decisions in various business and societal contexts.However,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause extraction.To address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment mechanisms.The model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause pairs.Second,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among tasks.The proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 score.Experimental results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its effectiveness.This research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-cause pair extraction.However,the study’s limitation lies in the data sources,potentially restricting the generalizability of the findings. 展开更多
关键词 Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms
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On the representations of string pairs over virtual field
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作者 TAO Kun FU Chang-Jian 《四川大学学报(自然科学版)》 北大核心 2025年第5期1103-1108,共6页
Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-represent... Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-representation is either a string representation or a band representation by using the coefficient quivers.It is worth noting that for a given band and a positive integer,there exists a unique band representation up to isomorphism. 展开更多
关键词 string pair string representation band representation
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Continuous Contact Model of Metamorphic Groove Pin Pair with Clearance
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作者 Jiangxue Hu Liang He +2 位作者 Yaping Wang Lihua Yang Ganwei Cai 《Applied Mathematics》 2025年第1期15-41,共27页
Metamorphic mechanism has the advantages of variable topology and variable degrees of freedom, which can realize the requirements of multi-conditions and multi-tasks, and has a good application prospect. The configura... Metamorphic mechanism has the advantages of variable topology and variable degrees of freedom, which can realize the requirements of multi-conditions and multi-tasks, and has a good application prospect. The configuration transformation is prominent feature of the metamorphic mechanism. The number of constraints or properties of the kinematic pairs provided by the metamorphic kinematic pairs will change under certain conditions, its dynamic performance is much more complex than that of traditional kinematic pairs with immutable constraints. However, the clearance model about traditional kinematic pairs with immutable constraints established by long-term research is difficult to be directly applied to the metachromatic kinematic pairs. Referring to the experience of the traditional kinematic pairs with immutable constraints, the continuous contact model of Metamorphic Groove pin pair with clearance is established. According to the traditional continuous contact model of the kinematic pairs with immutable constraints, the forces between the elements of kinematic pair of the mechanism with clearance and the ideal mechanism without clearance are regarded as the same, and the inertia force and inertia moment of the components are also calculated according to the acceleration of the ideal mechanism. The clearance is regarded as a massless virtual bar with length r. For the rotating pair part, the massless virtual bar length r is the difference between the radius of the shaft and the hole, and for the sliding pair part, the massless virtual bar length r is half of the difference between the height of the slider and the guide groove. According to the new mechanism without gap after adding the imaginary bar, kinetic energy and potential energy of the system are calculated for the two configurations of mechanism with metamorphic Groove pin pair with clearance. The kinetic energy and potential energy of the system are calculated according to the new mechanism without clearance after adding the massless virtual bar. The kinetic energy, potential energy and generalized force are substituted into the Lagrangian equation to obtain the motion equation of the metamorphic mechanism, which lays the foundation for the dynamic performance study of the mechanism with metamorphic groove pin pair with clearance. 展开更多
关键词 Metamorphic Mechanism Metamorphic pair with Clearance ContinuousContact Model Metamorphic Groove Pin pair
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基于Pair-Copula贝叶斯模型的基坑支护可靠度分析 被引量:1
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作者 吴大炜 江钰鑫 +1 位作者 梁广林 林越翔 《人民长江》 北大核心 2025年第1期140-146,163,共8页
为准确判定基坑安全状态,保障基坑安全建设,对影响基坑安全的关键因素展开时程监测,以Pair-Copula贝叶斯(Pair-Copula Bayesian Network, PCBN)模型为基础,结合Pair-Copula处理复杂多变量数据的灵活性和贝叶斯网络处理不确定性的优势,... 为准确判定基坑安全状态,保障基坑安全建设,对影响基坑安全的关键因素展开时程监测,以Pair-Copula贝叶斯(Pair-Copula Bayesian Network, PCBN)模型为基础,结合Pair-Copula处理复杂多变量数据的灵活性和贝叶斯网络处理不确定性的优势,对深基坑支护结构的可靠性进行了深入分析,构建了一套较为完善的可靠度评价体系,实现了考虑监测数据复杂相关性的基坑安全状态量化评价。研究结果表明:监测数据之间存在相关性,其中桩顶竖向位移、桩体水平位移、地表沉降、支撑轴力、桩(墙)体深层水平位移之间的Kendall秩相关系数均超过0.5,存在较强正相关性。地下水位与桩顶竖向位移、桩体水平位移、地表沉降、支撑轴力、桩(墙)体深层水平位移皆为负相关,且相关性较弱,地下水位与地表沉降之间Kendall秩相关系数为-0.361 7,相关性最弱。PCBN模型具有良好的精度,基于PCBN模型计算得到的新塘互通立交路段明挖法市政隧道深基坑工程可靠性指标β值为4.056,基坑支护结构位于安全范围。研究成果可为深基坑支护结构安全量化评价提供有效参考。 展开更多
关键词 深基坑支护 pair-Copula贝叶斯模型 风险评价 可靠度分析
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Tests of CP Symmetry in Entangled Hyperon Antihyperon Pairs at BESⅢ
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作者 Wenjing Zheng Andrzej Kupsc +4 位作者 Simone Pacetti Francesco Rosini Nora Salone Xiongfei Wang Shuang-shi Fang 《Chinese Physics Letters》 2025年第4期38-42,共5页
Decays of charmonium into hyperon and antihyperon pairs provide a pristine laboratory for exploring hyperon properties,such as their polarization and decay parameters,and for conducting tests of fundamental symmetries... Decays of charmonium into hyperon and antihyperon pairs provide a pristine laboratory for exploring hyperon properties,such as their polarization and decay parameters,and for conducting tests of fundamental symmetries.This brief review highlights the significant progress made in precise tests of CP symmetry at BESIII using entangled hyperon-antihyperon pairs。 展开更多
关键词 BESIII hyperon antihyperon pairs tests cp symmetry decay parameters CP symmetry decays charmonium hyperon antihyperon pairs polarization exploring hyperon
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Combination of Astragalus−Salvia and Ophiopogon−Dendrobium herb pairs alleviates Sjögren’s Syndrome via inhibiting the JAK1/STAT3 and PI3K/AKT pathways in NOD/Ltj mice
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作者 Peng Sun Lili Zhu +6 位作者 Yang Yu Sijing Hu Mengyi Shan Xuan Zhao Xinchang Wang Qiaoyan Zhang Luping Qin 《Chinese Journal of Natural Medicines》 2025年第6期733-741,共9页
Sjögren’s syndrome(SS)is an autoimmune disease characterized primarily by oral and periocular dryness.Astragalus-Salvia(AS)and Ophiopogon-Dendrobium(OD)represent two frequently utilized herb pairs in SS treatmen... Sjögren’s syndrome(SS)is an autoimmune disease characterized primarily by oral and periocular dryness.Astragalus-Salvia(AS)and Ophiopogon-Dendrobium(OD)represent two frequently utilized herb pairs in SS treatment.While the combination of AS-OD herb pairs demonstrates clinical efficacy in alleviating SS symptoms,its underlying mechanism remains unclear.This investigation sought to assess the therapeutic effects and elucidate the potential mechanisms of AS-OD in non-obese diabetic(NOD)/Ltj mice with SS.The study utilized NOD/Ltj mice as SS models,administering AS-OD treatment for 10 weeks at doses of 113.1,226.2,and 339.3 mg·d−1·20 g−1.Results demonstrated that AS-OD improved SS symptoms,evidenced by enhanced salivary flow rate,decreased anti-SSA/Ro and anti-SSB/La antibody levels,increased swimming duration,and reduced lactate(LA)and blood urea nitrogen(BUN)levels in NOD/Ltj mice.AS-OD reduced lymphocyte infiltration,enhanced Aquaporin-5(AQP5)expression in the submandibular gland,decreased inflammatory cytokine levels in the submandibular gland,and reduced the T helper type 17/regulatory T lymphocyte(Th17/Treg)cell ratio in the spleen.Transcriptomic and proteomic analyses indicated AS-OD’s involvement in regulating phosphatidylinositol-3-kinase/protein kinase B(PI3K/AKT)and Janus kinase 3/signal transducer and activator of transcription 3(JAK1/STAT3)pathways,with inhibitory effects validated in both NOD/Ltj mice submandibular gland and A-253 cells.Furthermore,AS-OD enhanced cell viability and reduced A-253 cell apoptosis through the PI3K/AKT pathway.In A-253 cells,AS-OD reduced inflammatory cytokine levels,CXC chemokine ligand 9/10(CXCL9/10),and T-cell chemotaxis by inhibiting the JAK1/STAT3 pathway.AS-OD mitigates SS by suppressing inflammation and immune responses through the PI3K/AKT and JAK1/STAT3 pathways. 展开更多
关键词 Sjgren’s syndrome Astragalus-Salvia herb pair Ophiopogon-Dendrobium herb pair CXCL9 and CXCL10 JAK1/STAT3 PI3K/AKT
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Controlled polymerization of functional acrylamides by rare-earth aryloxide-based Lewis pairs
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作者 Xian Xu Yiwen Guan Xin Xu 《Journal of Rare Earths》 2025年第10期2303-2310,I0008,共9页
A series of amine-bridged bis(phenolate)rare-earth(Sc,Y)aryloxides was synthesized and characterized.These complexes were successfully used for the controlled Lewis pair polymerization(LPP)of functional acrylamides in... A series of amine-bridged bis(phenolate)rare-earth(Sc,Y)aryloxides was synthesized and characterized.These complexes were successfully used for the controlled Lewis pair polymerization(LPP)of functional acrylamides in combination with phosphines,affording a new type of polyacrylamides with predictable molecular weight and low molecular weight distribution.The living nature of this LPP was verified by near-quantitative initiation efficiencies,a linear increase of molecular weight vs monomer-to-initiator ratio and monomer conversion,chain extensions,and the synthesis of well-defined block copolymers.The mechanistic studies were performed through the isolation of a zwitterionic intermediate as well as the end-chain analysis of oligomers,showcasing a rare-earth/phosphine cooperation.Furthermore,the resultant polyacrylamides exhibit outstanding thermal stability and great potential for application in photovoltaic devices. 展开更多
关键词 Rare earths Lewis pair Living/controlled polymerization POLYACRYLAMIDE
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An extended(2+1)-dimensional modified Korteweg-de Vries-Calogero-Bogoyavlenskii-Schiff equation:Lax pair and Darboux transformation
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作者 Li Cheng Yi Zhang Wen-Xiu Ma 《Communications in Theoretical Physics》 2025年第3期12-20,共9页
The aim of this paper is to study an extended modified Korteweg-de Vries-Calogero-Bogoyavlenskii-Schiff(mKdV-CBS)equation and present its Lax pair with a spectral parameter.Meanwhile,a Miura transformation is explored... The aim of this paper is to study an extended modified Korteweg-de Vries-Calogero-Bogoyavlenskii-Schiff(mKdV-CBS)equation and present its Lax pair with a spectral parameter.Meanwhile,a Miura transformation is explored,which reveals the relationship between solutions of the extended mKdV-CBS equation and the extended(2+1)-dimensional Korteweg-de Vries(KdV)equation.On the basis of the obtained Lax pair and the existing research results,the Darboux transformation is derived,which plays a crucial role in presenting soliton solutions.In addition,soliton molecules are given by the velocity resonance mechanism. 展开更多
关键词 extended mKdV-CBS equation Lax pair Darboux transformation soliton solution
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Microfluidic reactors for paired electrosynthesis:Fundamentals,applications and future prospects
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作者 Hao Xue Zhi-Hao Zhao +1 位作者 Menglei Yuan Guangjin Zhang 《Green Energy & Environment》 2025年第3期471-499,共29页
Paired electrosynthesis has received considerable attention as a consequence of simultaneously synthesizing target products at both cathode and anode,whereas the related synthetic efficiency in batch reactors is still... Paired electrosynthesis has received considerable attention as a consequence of simultaneously synthesizing target products at both cathode and anode,whereas the related synthetic efficiency in batch reactors is still undesirable under certain circumstances.Encouragingly,laminar microfluidic reactor offers prospective options that possess controllable flow characteristics such as enhanced mass transport,precise laminar flow control and the ability to expand production scale progressively.In this comprehensive review,the underlying fundamentals of the paired electrosynthesis are initially summarized,followed by categorizing the paired electrosynthesis including parallel paired electrosynthesis,divergent paired electrosynthesis,convergent paired electrosynthesis,sequential paired electrosynthesis and linear paired electrosynthesis.Thereafter,a holistic overview of microfluidic reactor equipment,integral fundamentals and research methodology as well as channel extension and scale-up strategies is proposed.The established fundamentals and evaluated metrics further inspired the applications of microfluidic reactors in paired electrosynthesis.This work stimulated the overwhelming investigation of mechanism discovery,material screening strategies,and device assemblies. 展开更多
关键词 paired electrosynthesis Microfluidic reactor Laminar flow Scaling-up strategy
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A Characterization of the n-F-Tilting Pair
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作者 Mengxue TIAN Dajun LIU Yuxia MEI 《Journal of Mathematical Research with Applications》 2025年第4期445-459,共15页
Tilting pair is a key concept in the tilting theory.Let F be an additive subfunctor of the functor Ext_(A)^(1)(-,-).In this paper,we introduce the note of n-F-tilting pair,which is a natural generalization of n-tiltin... Tilting pair is a key concept in the tilting theory.Let F be an additive subfunctor of the functor Ext_(A)^(1)(-,-).In this paper,we introduce the note of n-F-tilting pair,which is a natural generalization of n-tilting pair in the sense of Miyahita.Some propositions and a simplified characterization on n-F-tilting pairs are given. 展开更多
关键词 F-exact sequences F-selforthogonal modules n-F-tilting pairs tilting theory
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Microenvironment modulation around frustrated Lewis pairs in Ce-based metal-organic frameworks for efficient catalytic hydrogenation
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作者 Xinmeng Xu Zuoshuai Xi +6 位作者 Hongyi Gao Danfeng Zhao Zhiyuan Liu Tao Ban Jingjing Wang Shunzheng Zhao Ge Wang 《Chinese Journal of Catalysis》 2025年第8期59-72,共14页
The development of solid frustrated Lewis pairs(FLPs)catalysts with porous structures is a promising strategy for advancing green hydrogenation technologies and has garnered significant attention.Leveraging the divers... The development of solid frustrated Lewis pairs(FLPs)catalysts with porous structures is a promising strategy for advancing green hydrogenation technologies and has garnered significant attention.Leveraging the diverse oxidation states and structural tunability of cerium-based metal-organic frameworks(Ce-MOFs),this study employed a competitive coordination strategy utilizing a single carboxylate functional group ligand to construct a series of MOF-808-X(X=-NH_(2),-OH,-Br,and-NO_(2))featuring rich solid-state FLPs for hydrogenation of unsaturated olefins.The-X functional group serves as a microenvironment,enhancing hydrogenation activity by modulating the electronic properties and acid-base characteristics of the FLP sites.The unique redox properties of elemental cerium facilitate the exposure of unsaturated Ce sites(Ce-CUS,Lewis acid(LA))and adjacent Ce-OH(Lewis base(LB))sites within the MOFs,generating abundant solid-state FLP(Ce-CUS/Ce-OH)sites.Experimental results demonstrate that Ce-CUS and Ce-OH interact with theσandσ^(*)orbitals of H-H,and this"push-pull"synergy promotes heterolytic cleavage of the H-H bond.The lone pair electrons of the electron-donating functional group are transmitted through the molecular backbone to the LB site,thereby increasing its strength and reducing the activation energy required for H_(2)heterolytic cleavage.Notably,at 100℃and 2 MPa H_(2),MOF-808-NH_(2)achieves complete conversion of styrene and dicyclopentadiene,significantly outperforming MOF-808.Based on in-situ analysis and density functional theory calculations,a plausible reaction mechanism is proposed.This research enriches the theoretical framework for unsaturated olefin hydrogenation catalysts and contributes to the development of efficient catalytic systems. 展开更多
关键词 Frustrated Lewis pairs Microenvironment modulation Defect Ce-based metal-organic frameworks Catalyst Hydrogenation
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Frustrated lewis pairs regulated solid polymer electrolyte enables ultralong cycles of lithium metal batteries
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作者 Pingping Chang Zhenjie Liu +5 位作者 Murong Xi Yong Guo Tianlong Wu Juan Ding Hongtao Liu Yudai Huang 《Advanced Powder Materials》 2025年第1期115-123,共9页
Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic... Long-cycling dendrite-free solid-state lithium metal batteries (LMBs) require fast and uniform lithium-ion (Liþ)transport of solid-state electrolytes (SSEs). However, the SSEs still face the problems of low ionic conductivity, lowLiþ transference number, and unstable interface with lithium metal. In this work, a novel strategy of frustratedLewis pairs (FLPs) modulating solid polymer electrolytes (SPEs) has been firstly proposed that enables durable Lireversible cycling. The tunable strength of Lewis acid and base dual-active sites of nickel borate FLPs can syn-ergisticallypromote both the dissociation of lithium salts and the transfer of Liþ. As a consequence, the FLPsmodulated SPEs (SPE-NiBO-150) exhibit high ionic conductivity of 4.92×10^(-4)S cm^(-1), high Liþ transferencenumber of 0.74, and superior interface compatibility with both lithium anode and LiFePO4 cathode at room-temperature.The Li//SPE-NiBO-150//Li symmetric cell demonstrates ultralong cycle stability (over 10,000 h(417 days) at both current density of 0.2 and 0.5 mA cm〓〓2), and the assembled solid-state LiFePO4//SPE-NiBO-150//Libattery also shows excellent performance (86% capacity retention for 300 cycles at 0.5C). The presentwork supplies a new insight into designing high-performance SPEs for solid-state LMB applications. 展开更多
关键词 Dual-active sites Frustrated lewis pairs Ultralong-cycling Solid-state electrolytes Lithium metal batteries
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Pediatric inflammatory bowel disease in mother-child pairs: clinical risk factors and gut microbiota characteristics
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作者 Cunzheng ZHANG Ruqiao DUAN +7 位作者 Nini DAI Yuzhu CHEN Gaonan LI Xiao'ang LI Xiaolin JI Xuemei ZHONG Zailing LI Liping DUAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第10期995-1014,共20页
Objective:The risk factors and role of mother–child gut microbiota in pediatric inflammatory bowel disease(PIBD)remain unclear.We aimed to explore the clinical risk factors associated with PIBD,analyze the characteri... Objective:The risk factors and role of mother–child gut microbiota in pediatric inflammatory bowel disease(PIBD)remain unclear.We aimed to explore the clinical risk factors associated with PIBD,analyze the characteristics of gut microbiota of children and their mothers,and examine the correlation of the microbial composition in mother–child pairs.Methods:We conducted a case-control study including children with PIBD and their mothers as the case group,as well as healthy children and their mothers as the control group.Questionnaires were used to collect information such as family illness history and maternal and early-life events.Fecal samples were collected from the children and mothers for microbiota 16S ribosomal RNA(rRNA)sequencing to analyze the composition and its potential association with PIBD.Results:A total of 54 pairs of cases and 122 pairs of controls were recruited.A family history of autoimmune disease and antibiotic use during pregnancy were associated with an increased risk of PIBD,and a higher education level of the father was associated with a decreased risk of PIBD.Children with PIBD and mothers exhibited different gut microbiota compared to healthy children and mothers.Similarities were observed in the gut microbiota of mothers and children in the same groups.Some bacterial biomarkers of mothers discovered in this study had the power to predict PIBD in their offspring.Conclusions:PIBD is influenced by maternal risk factors and has unique gut microbiota characteristics.The mother–child gut microbiota is closely related,suggesting the transmission and influence of the gut microbiota between mothers and children.This study highlights the potential pathogenesis of PIBD and provides a basis for developing targeted interventions. 展开更多
关键词 Inflammatory bowel disease(IBD) Risk factor Gut microbiota Mother-child pair
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INEQUALITIES FOR THE CUBIC PARTITIONS AND CUBIC PARTITION PAIRS
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作者 Chong LI Yi PENG Helen W.J.ZHANG 《Acta Mathematica Scientia》 2025年第2期737-754,共18页
In this paper,we examine the functions a(n)and b(n),which respectively represent the number of cubic partitions and cubic partition pairs.Our work leads to the derivation of asymptotic formulas for both a(n)and b(n).A... In this paper,we examine the functions a(n)and b(n),which respectively represent the number of cubic partitions and cubic partition pairs.Our work leads to the derivation of asymptotic formulas for both a(n)and b(n).Additionally,we establish the upper and lower bounds of these functions,factoring in the explicit error terms involved.Crucially,our findings reveal that a(n)and b(n)both satisfy several inequalities such as log-concavity,third-order Turan inequalities,and strict log-subadditivity. 展开更多
关键词 asymptotic formula LOG-CONCAVITY third-order Turan inequalities cubic partition cubic partition pair
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Ultralow-coordinated Ni species boosting paired electrosynthesis of formate from waste plastic and carbon dioxide
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作者 Tao Chen Qizhi Hu +7 位作者 Chao Wu Mingdong Sun Ping Fu Xiaoling Liu Yulong Li Yu Zhou Shibo Xi Jun Wang 《Journal of Energy Chemistry》 2025年第8期285-295,共11页
Paired electrolysis of waste feedstocks holds an energy-efficient alternative for chemical production;however,the sluggish anodic oxidation limited the total efficiency under larger current density.Herein,we construct... Paired electrolysis of waste feedstocks holds an energy-efficient alternative for chemical production;however,the sluggish anodic oxidation limited the total efficiency under larger current density.Herein,we constructed ultralow-coordinated Ni species with Ni–O coordination number of∼3 via a hydrothermal synthesis-sulfidation-annealing process and electrochemical activation and demonstrated the vital role in accelerating the proton deintercalation and reactive oxygen intermediate·OH formation during electro-reforming polyethylene terephthalate hydrolysate(POR).The target catalyst NiCoSx/NF afforded a high formate productivity of 7.4 mmol cm^(−2)h^(−1)at∼600 mA cm^(−2)with a formate Faradic efficiency(FE_(formate))of 92.4%in POR and maintained a FE_(formate)of∼90%for 100 h at 2 A in a membrane electrode assembly electrolyzer.Coupling POR on NiCoSx/NF with carbon dioxide reduction reaction on oxygen vacancies enriched Vo-BiSnO reached effective concurrent formate production with 172.7%of FE_(formate)at 500 mA cm^(−2)and long-term stability.Such excellent performance shows the great prospect of electrocatalyst design by regulating the local metal environment. 展开更多
关键词 Electrocatalytic oxidation Plastic upcycling CO_(2)reduction FORMATE paired electrolysis
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Constructing frustrated Lewis pairs on porous Ce-based metal-organic frameworks with improved dicyclopentadiene hydrogenation activity
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作者 Danfeng Zhao Jing Lin +4 位作者 Rushuo Li Liang Chu Zhaokun Wang Xiubing Huang Ge Wang 《Chinese Chemical Letters》 2025年第7期619-625,共7页
The construction of frustrated Lewis acid-base pairs(FLPs)in porous systems is very important for the field of industrial hydrogenation catalysis,but there is still a great challenge.Based on the Ce^(3+)/Ce^(4+)redox ... The construction of frustrated Lewis acid-base pairs(FLPs)in porous systems is very important for the field of industrial hydrogenation catalysis,but there is still a great challenge.Based on the Ce^(3+)/Ce^(4+)redox pairs and abundant defects in porous Ce-based metal-organic frameworks(Ce-MOFs),FLP sites consisting of ligand-defective Ce sites(Lewis acid,LA)and neighboring terminal O sites(Lewis base,LB)were constructed in situ by a simple vacuum thermal activation method in lamellar Ce-UiO-66-F.Defects/oxygen vacancies in the Ce-MOFs structure result in the difference in the electron cloud density between Ce and O,which is suitable for H-H hetero-cleavage and H-transfer in the dicyclopentadiene(DCPD)hydrogenation process.Particularly,Ce-UiO-66-F-200 achieved 96.9%conversion of DCPD and 97.8%selectivity of 8,9-dihydrodicyclopentadiene(8,9-DHDCPD)at 100℃ under 2MPa H2 for 10 h,which is 9.4 times higher than 10.2%conversion of DCPD over the unactivated Ce-UiO-66-F.This research promotes the understanding of solid MOFs-based porous FLPs for H_(2) activation,and encourages the in-depth investigation of surface solid FLPs to the whole material FLPs. 展开更多
关键词 Ce-based metal−organic framework Frustrated Lewis pairs Hydrogen activation Thermocatalytic hydrogenation
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Research progress on therapeutic material basis and mechanism of Scutellaria barbata–Lobelia chinensis herb pair in the treatment of lung cancer
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作者 Xiao-Yun Liang Ke-Jin Xu +3 位作者 Jia Liu Wei-Dong Li Hai-Bing Hua Chen-Xu Wei 《Integrative Medicine Discovery》 2025年第21期1-12,共12页
Lung cancer remains a leading cause of cancer-related mortality globally,with conventional therapies(chemotherapy,targeted agents)limited by severe toxicities and poor durability.Traditional Chinese medicine(TCMs)herb... Lung cancer remains a leading cause of cancer-related mortality globally,with conventional therapies(chemotherapy,targeted agents)limited by severe toxicities and poor durability.Traditional Chinese medicine(TCMs)herb pairs,particularly Scutellaria barbata–Lobelia chinensis(SL),have emerged as promising alternatives for their multitarget anti-lung cancer activity,but their material basis and mechanisms need systematic clarification.In TCM practice,SL herb pair exerts“heat-clearing and toxin-resolving”effects,aligning with the therapeutic principle of“resolving toxin to suppress tumor”for lung cancer.Phytochemical and pharmacological studies confirm its key active components,including flavonoids(baicalein,luteolin,quercetin),alkaloids,and polysaccharides.These components synergistically act through core signaling pathways:inhibiting angiogenesis via HIF-1α/VEGF axis;inducing apoptosis/autophagy through PI3K/AKT/mTOR and SIRT1/AMPK pathways;suppressing epithelial-mesenchymal transition(EMT)by targeting TGF-β/Smad and Wnt/β-catenin pathways;and regulating immune microenvironment via NLRP3 inflammasome and Th1/Th2 balance.This review systematically summarizes the multi-component(flavonoids,alkaloids)and multi-pathway mechanisms of SL herb pair,validating the scientific connotation of TCM’s“multi-target therapy”paradigm.It provides a theoretical basis for clinical application of SL herb pair and inspires the development of innovative lung cancer therapies(e.g.,component-based nano-drugs),bridging TCM practice with modern pharmacology. 展开更多
关键词 Scutellaria barbata Lobelia chinensis herbal pair lung cancer therapeutic material basis action mechanism
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Tailor of frustrated Lewis pairs in Ag/CeO_(2) for producing 4-aminophenol
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作者 Huaiquan Zhao Hongye Bai +5 位作者 Zhenzhen Huang Guanhua Wang Hongliang Dai Xuliang Pang Hongping Li Weiqiang Fan 《Green Energy & Environment》 2025年第7期1583-1595,共13页
Catalytic reduction of 4-nitrophenol(4-NP)pollutant to the high-value 4-aminophenol(4-AP)with a clean hydrogen donor holds significant importance yet great challenges owing to the difficult activation of nitro and H s... Catalytic reduction of 4-nitrophenol(4-NP)pollutant to the high-value 4-aminophenol(4-AP)with a clean hydrogen donor holds significant importance yet great challenges owing to the difficult activation of nitro and H species.In this work,Ag tailoring Frustrated Lewis pairs(FLPs)of CeO_(2)(Ag/CeO_(2))were successfully fabricated for electrochemical reduction reaction of 4-NP(4-NP ERR).As a result,the bond of Ag with O atom changed the state of the Ce-O bond and electron density,where the tailored FLPs were the key factor for enhancing absorption and activation.The reaction rate of Ag/CeO_(2)reached up to 4.70 mmol·min^(-1)(Faraday efficiency:99.5%),which was about four times of CeO_(2).Additionally,this study delved into the proton-coupled electron processes to further understand the mechanism of 4-NP ERR.Therefore,in this study,we have endeavored to investigate the role of tailored FLPs sites and utilize this structure-function relationship to achieve environmentalfriendly chemical synthesis. 展开更多
关键词 4-nitrophenol pollutant 4-aminophenol Electrochemical reduction reaction Tailored frustrated Lewis pairs
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