检索结果-南通市图书馆

Greedy Lattice Paths with General Weights

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第9期40卷 2213-2222页

作者： Yin shan CHANG An Qi ZHENG College of Mathematics Sichuan UniversityChengdu 610065P.R.China

Let{X_(v):v∈Z^(d)}be *** *** S(π)=Σ_(v∈π)X_(v)be the weight of a self-avoiding lattice pathπ.Let M_(n)=max{S(π):πhas length n and starts from the origin}.We are interested in the asymptotics of Mn as n→∞.This model is closely related to the first passage percolation when the weights{X_(v):v∈Z^(d)}are non-positive and it is closely related to the last passage percolation when the weights{X_(v):v∈Z^(d)}are *** general weights,this model could be viewed as an interpolation between first passage models and last passage ***,this model is also closely related to a variant of the position of right-most particles of branching random *** the two assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)ve that there exists a finite real number M such that Mn/n converges to a deterministic constant M in L^(1)as n tends to *** under the stronger assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)ve that M_(n)/n converges to the same constant M almost surely as n tends to infinity.

关键词： Last passage percolation first passage percolation greedy lattice path

Combined effects of sea urchin-like structure and mixed Cu^(+)/Cu^(0)states on promoting C_(2)formation in electrocatalytic CO_(2)reduction

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2024年第3期18卷 63-73页

作者： Mengqing shan Dongsheng Lu Jiatong Dong Shen Yan Jinyu Han Hua Wang Collaborative Innovation Center of Chemical Science and Engineering Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin300354China

Surface engineering and Cu valence regulation are essential factors in improving the C_(2)selectivity during the electrochemical reduction of CO_(2).Herein,we present a sea urchin-like CuO/Cu_(2)O catalyst derived from rhombic dodecahedra Cu_(2)O through one-step oxidation/etching method where the mixed Cu^(+)/Cu^(0)states are formed via in situ reduction during *** combined effects of the morphology and the mixed Cu^(+)/Cu^(0)states on C–C coupling are evaluated by the Faradaic efficiency of C_(2)and the C_(2)/C1 ratio obtained in an H-cell.R-Cu^(O)/Cu_(2)O exhibited 49.5%Faradaic efficiency of C_(2)with a C_(2)/C1 ratio of 3.1 at−1.4 v *** hydrogen electrode,which are 1.5 and 3.2 times higher than those of R-Cu_(2)O,*** a flow-cell,68.0%Faradaic efficiency of C_(2)is achieved at a current density of 500 mA·cm^(−2).The formation of the mixed Cu^(+)/Cu^(0)states was confirmed by in situ Raman ***,the sea urchin-like structure provides more active sites and enables faster electron *** a result,the excellent C_(2)production on R-CuO/Cu_(2)O is primarily attributed to the synergistic effects of the sea urchin-like structure and the stable mixed Cu^(+)/Cu^(0)***,this work presents an integrated strategy for developing Cu-based electrocatalysts for C_(2)production through electrochemical CO_(2)reduction.

关键词： CO_(2)electrolysis sea urchin-like structure Cu^(+)/Cu^(0) C_(2)products

Enhanced electric-field induced strain in Eu^(3+) doped 0.67BiFeO_(3)-0.33BaTiO_(3) lead-free piezoelectric ceramics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第9期42卷 1747-1754,I0004页

作者： Wei Li Tongxiang Liang Xiang He vyunov Oleg Dongfang Pang shan Wu College of Rare Earths Jiangxi University of Science and TechnologyGanzhou341000China Key Laboratory of High Performance Ceramics and Ultrastructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai201800China

Lead-free ferroelectric ceramics,0.67Bi_(1-x)Eu_(x)FeO_(3)-0.33BaTiO_(3)(BF-BT-xEu,x=0-0.02),were prepared via a solid-state reaction,The effect of Eu^(3+) doping on the microstructure,dielectric properties,ferroelectric properties,and electric-field-induced strain was *** X-ray diffraction(XRD) results indicate the presence of a mixed phase of tetragonal and rhombohedral at the morphotropic phase boundary(MPB).Doping with an appropriate amount of Eu^(3+) reduces the Fe^(3+) content and decreases the leakage current in the binary system.A converse piezoelectric coefficient(d_(33)*) of 392 pm/v is obtained at BF-BT-0.003Eu under an electric field of 60 kv/cm at room temperature,which has a Curie temperature(T_(C)) of 414℃,The unipolar strain and d_(33)* of BF-BT-0.003Eu ceramics increase to 0.438%and 730 pm/v at 125℃ The field-induced strain response of the BF-BT-0.003Eu ceramics is greater than that of 0.67BF-0.33BT,mainly due to its optimal grain size,reduction of leakage current,and coexistence of ferroelectric-relaxation phases,BF-BT-0.003Eu ceramic is a lead-free candidate for high-temperature actuator applications.

关键词： Ferroelectric Field-induced strain Ceramics Lead-free Rare earths

Small holes,big impact:Stomata in plant–pathogen–climate epic trifecta

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2024年第1期17卷 26-49页

作者： Shuguo Hou Olivier Rodrigues Zunyong Liu Libo shan Ping He Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agriculture Sciences in WeifangWeifangShandong 261325China School of Municipal&Environmental Engineering Shandong Jianzhu UniversityJinanShandong 250101China Unitéde Recherche Physiologie Pathologie et Génétique VégétalesUniversitéde Toulouse Midi-PyrénéesINP-PURPAN31076 ToulouseFrance Department of Molecular Cellularand Developmental BiologyUniversity of MichiganAnn ArborMI 48109USA

The regulation of stomatal aperture opening and closure represents an evolutionary battle between plants and pathogens,characterized by adaptive strategies that influence both plant resistance and pathogen *** ongoing climate change introduces further complexity,affecting pathogen invasion and host *** review delves into recent advances on our understanding of the mechanisms governing immunity-related stomatal movement and patterning with an emphasis on the regulation of stomatal opening and closure dynamics by pathogen patterns and host *** addition,the review explores how climate changes impact plant–pathogen interactions by modulating stomatal *** light of the pressing challenges associated with food security and the unpredictable nature of climate changes,future research in this field,which includes the investigation of spatiotemporal regulation and engineering of stomatal immunity,emerges as a promising avenue for enhancing crop resilience and contributing to climate control strategies.

关键词： stomatal movement stomatal patterning plant resistance pathogen virulence apoplastic immunity and climate change

Design and synthesis of polyoxovanadate-based framework for efficient dye degradation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tungsten 2024年第2期6卷 447-453页

作者： Qing Lan Su-Juan Jin Zheng Wang Xu-Yang Li Yan Xiong Zhuo-Cheng Wang shan-shan Liu Zhi-Ming Zhang Qiang Zhao Engineering Technology Research Center of Henan Province for Solar Catalysis School of Chemical and Pharmaceutical EngineeringNanyang Normal UniversityNanyang 473061China Institute of New Energy Materials&Low Carbon Technology Tianjin University of TechnologyTianjin 300384China

A new polyoxovanadate-based framework material[Cu(en)_(2)]_(4)v_(18)O_(42)(H_(2)O)·6H_(2)O(1)was designed and synthesized by hydrothermal reaction of NavO_(3),Cu(NO_(3))_(2)·6H_(2)O and 1,2-diaminoethane(en)via carefully adjusting the pH value of the reaction *** structure of the title compound has been determined by single-crystal X-ray diff raction analysis,thermogravimetric analysis,infrared spectra and elemental *** structural analysis demonstrate the three-dimensional(3D)framework structure of compound 1,which was composed of the[v_(18)O_(42)(H_(2)O)]_(8)−({v_(18)O_(42)(H_(2)O)})anions linked by the Cu^(2+)*** 1 represents the fi rst 3D framework based on{v_(18)O_(42)(H_(2)O)}polyoxoanions and copper ***-driven degradation of residual organic pollutants in industrial wastewater is still a major problem for human *** experiments reveal that compound 1 possesses of excellent photocatalytic activity for the degradation of methylene blue and rhodamine B.

关键词： Polyoxovanadate Framework Polyoxovanadate-based framework Photocatalytic Organic pollutants

Mitigation of Deane and Hamill phenomenon in gallium nitride high-voltage power supply for electric propulsion system application

在线全文

学校读者我要写书评

暂无评论

High voltage 2024年第1期9卷 252-265页

作者： Minghai Dong Hui Li shan Yin Kye Yak See Yingzhe Wu Xiong Xin School of Aeronautics&Astronautics University of Electronic Science and Technology of ChinaChengduChina School of Electrical&Electronic Engineering Nanyang Technological UniversitySingaporeSingapore School of Automation Engineering University of Electronic Science and Technology of ChinaChengduChina Innoscience(Shenzhen)Semiconductor Co.Ltd. ShenzhenChina

The step-up resonant converters are widely adopted to provide high voltage in kv-level for electric propulsion system due to their high efficiency,low mass,modularisation,and high-power *** bipolar Cockcroft-Walton voltage multiplier(BiCWvM)is a major circuit that steps up the voltage in the resonant ***,the diode nonlinearity in BiCWvM can introduce self-sustained quasi-periodic oscillations in the voltage and current waveforms,which is commonly known as the Deane and Hamill(DH)*** oscillation can lead to higher magnetic loss and control failure,and it is more likely to present in the gallium nitride-based converter due to the highfrequency *** authors aim to investigate and mitigate the DH phenomenon systematically so that proper mitigation can be *** facilitate the investigation,the circuit before the BiCWvM in the converter is derived and modelled as a voltage source v_(m)and a series inductor L_(sy).Also,the reverse recovery process of the diode in the BiCWvM can be represented by a piecewise-linear(PWL)model,with the simplified circuit and PWL model,the relationship between voltage and current under different operating conditions can be determined with *** relationship allows to understand the mechanism of diode reverse recovery in BiCWvM that leads to DH ***,a hybrid-/full-silicon carbide(SiC)design is proposed to mitigate the DH phenomenon,which is verified experimentally for a 300-kHz,5-W,20-v/1.5-kv GaN-based step-up resonant converter.

关键词： power resonant high

Ultra-conservative noncoding RNA uc.243 confers chemo-resistance by facilitating the efflux of the chemotherapeutic drug in ovarian cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

BIOCELL 2024年第8期48卷 1265-1273页

作者： shan JIANG XIUFENG LIN YANFEI CHEN XINNING LI JIALI KANG Department of Gynecology and Obstetrics The First Affiliated Hospital of Jinan UniversityGuangzhou510180China Reproductive Medical Center Boai Hospital of Zhongshan Affiliated to Southern Medical UniversityZhongshan528400China Department of Gynecology and Obstetrics Boai Hospital of Zhongshan Affiliated to Southern Medical UniversityZhongshan528400China Department of Gynecology and Obstetrics Guangzhou First People’s HospitalGuangzhou Medical UniversityGuangzhou510180China

Background:Despite improvements in objective response rates to cisplatin-based combination chemotherapy,the majority of advanced ovarian cancer remains suboptimal,resulting in poor *** has been found that non-coding RNAs(ncRNAs)not only participate in the transmission of signals between various cells but also participate in tumor immunity and anti-tumor immune responses,thereby regulating tumor occurrence and ***,the function and detailed mechanism of ultraconserved RNA(ucRNA)in ovarian cancer chemoresistance is still ***:Western blotting assay,Quantitative real-time PCR analysis(qPCR),and Kaplan-Meier Plotter analysis were performed to analyze the expression and prognosis of uc.243 in ovarian *** assay and Annexin v assay were performed to analyze the function of uc.243 in cisplatin resistance in ovarian cancer *** pull-down and qPCR experiments were performed to explore the molecular mechanism of uc.243 enhancing cisplatin resistance in ovarian cancer ***:Herein,we found that uc.243 was remarkably upregulated and correlated with patient survival in chemoresistance ovarian cancer patients compared with chemo-sensitive ovarian *** experiment displayed that uc.243 induced cisplatin resistance on ovarian cancer cells by facilitating the efflux of cisplatin(CDDP);but inhibiting the expression of uc.243 significantly reverses this ***,uc.243 can inhibit the binding of RNA binding protein DGCR8 microprocessor complex subunit to pri-miR-155,thereby inhibiting the cleavage of pri-miR-155 and decrease in mature miR-155,subsequently upregulates the expression of ATP binding cassette subfamily B member(ABCB1,ABCC2).Conclusion:Our research findings indicate that uc.243 can induce chemotherapy resistance in ovarian cancer,suggesting that it may become a new prognostic biomarker for malignant ovarian cancer.

关键词： Ultra-conserved non-coding RNA uc.243 Drug efflux Drug transporters Chemoresistance Ovarian cancer

Tuning interface mechanism of FeCo alloy embedded N,S-codoped carbon substrate for rechargeable Zn-air battery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第6期93卷 400-410,I0010页

作者： Hui Chang Lulu Zhao shan Zhao Zong-Lin Liu Peng-Fei Wang Ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004HebeiChina

The interface mechanism between catalyst and carbon substrate has been the focus of *** this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis *** experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon *** FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 v)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mv)for *** addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle *** results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.

关键词： FeCo alloy N S co-doped carbon DFT calculation Zn-air batteries Interfacial interaction

Conversion-type anode chemistry with interfacial compatibility toward Ah-level near-neutral high-voltage zinc ion batteries

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第7期11卷 226-238页

作者： shan Guo Liping Qin Jia Wu Zhexuan Liu Yuhao Huang Yiman Xie Guozhao Fang Shuquan Liang School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan ProvinceCentral South University College of Biological and Chemical Engineering Guangxi University of Science and Technology Information and Network Center Central South University

High-voltage aqueous zinc ion batteries（AZIBs） with a high-safety near-neutral electrolyte is of great significance for practical sustainable application; however, they suffer from anode and electrode/electrolyte interfacial incompatibility. Herein, a conversion-type anode chemistry with a low anodic potential, which is guided by the Gibbs free energy change of conversion reaction, was designed for high-voltage near-neutral AZIBs. A reversible conversion reaction between ZnC2O4·2H2O particles and three-dimensional Zn metal networks well-matched in CH3COOLi-based electrolyte was revealed. This mechanism can be universally validated in the battery systems with sodium or iodine ions. More importantly, a cathodic crowded micellar electrolyte with a water confinement effect was proposed in which lies the core for the stability and reversibility of the cathode under an operating platform voltage beyond 2.0 v, obtaining a capacity retention of 95% after 100 cycles. Remarkably, the scientific and technological challenges from the coin cell to Ah-scale battery, sluggish kinetics of the solid-solid electrode reaction, capacity excitation under high loading of active material, and preparation complexities associated with large-area quasi-solid electrolytes,were explored, successfully achieving an 88% capacity retention under high loading of more than 20 mg cm-2and particularly a practical 1.1 Ah-level pouch cell. This work provides a path for designing low-cost, eco-friendly and high-voltage aqueous batteries.

关键词： zinc compound anode conversion reaction voltage regulation interfacial design pouch cell