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A Local Tb Theorem for Square Functions and Parabolic Layer Potentials

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1941-1966页

作者： Zhi dan WAnG Guo Ming ZHAnG School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816P.R.China Frontiers Science Center for nonlinear Expectations Ministry of EductionResearch Center for Mathematics and Interdisciplinary SciencesShandong UniversityQingdao266237P.R.China

In this paper,we give a locally parabolic version of Tb theorem for a class of vector-valued operators with off-diagonal decay in L^(2) and certain quasi-orthogonality on a subspace of L^(2),in which the testing functions themselves are also *** an application,we establish the boundedness of layer potentials related to parabolic operators in divergence form,defined in the upper half-space Rn+2+:={(x,t,λ)∈R^(n+1)×(0,∞)},with uniformly complex elliptic,L^(∞),t,λ-independen. coefficients,and satisfying the De Giorgi/nash estimates.

关键词： Local Tb theorems Calderon-Littlewood-Paley family Parabolic layer potentials Carleson measure estimates

Existence of Positive Solutions to a Fractional-Kirchhoff System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 225-240页

作者： Peng-fei Li Jun-hui Xie dan Mu School of Mathematics and Statistics Hubei Minzu UniversityEnshi445000China

LetΩbe a bounded smooth domain in Rn(n≥3).Assuming that 00 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x... 详细信息

LetΩbe a bounded smooth domain in Rn(n≥3).Assuming that 0n+2s/n-2s with(p,q)≠(n+2s/n-2s,n+2s/n-2s),and a,b>0 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x,u,v,▽u,▽v),x∈Ω,(-Δ)^(s)v=u^(q)+h_(2)(x,u,▽,▽u,▽v),x∈Q,u,v>0,x∈Ω,u=v=0,x∈Rn\Ω.Under some assumptions of hi(x,u,v,▽u,▽v)(i=1,2),we get a priori bounds of the positive solutions to the problem(1.1)by the blow-up methods and rescaling *** on these estimates and degree theory,we establish the existence of positive solutions to problem(1.1).

关键词： fractional-Kirchhoff system a priori bounds degree theory positive solution

Partition-based network Equivalent Method for Power System Subsynchronous Oscillation Analysis

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 313-320页

作者： Chenxuan Wang Weimin Zheng Zhen Wang Yangqing dan Ping Ju the Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China the College of Energy and Electrical Engineering Hohai UniverstiyNanjing 211100China

Given large-scale modern power systems with pow er electronic converters,the numerical simulation with subsyn chronous oscillation(SSO)faces great challenges in engineering practice due to sharply enlarged modeling scale and high com putational *** reduce the modeling scale,network parti tion and equivalent becomes a vital technique in numerical sim *** several methods have been developed for net work equivalent,a generally accepted rule for network parti tion is still *** paper proposes that the system can be partitioned into three parts,i.e.,the internal,the middle,and the external subsystems,in which the internal subsystem consists of all power electronic components,the middle subsys tem includes those selected AC dynamic components with de tailed models,and the remaining components and buses consti tute the external *** external subsystem is further represented by an equivalent RLC network determined by the frequency dependen. network equivalent(FDnE)*** the proposed method,the observability index and the electrical distance index are used to iden.ify the interface between the middle and the external *** studies based on a modified Hydro-Quebec system are used to verify the effective ness of the proposed method.

关键词： Electrical distance network equivalent subsyn chronous oscillation observability index

Impact of thoracic paravertebral block and sufentanil on outcomes and postoperative cognitive dysfunction in thoracoscopic lung cancer surgery

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World Journal of Psychiatry 2024年第6期14卷 894-903页

作者： dan-dan Wang Hong-Yu Wang Yan Zhu Xi-Hua Lu Department of Anesthesiology The Affiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalZhengzhou 450008Henan ProvinceChina

BACKGROUnD Postoperative pain management and cognitive function preservation are crucial for patients undergoing thoracoscopic surgery for lung cancer(LC).This is achieved using either a thoracic paravertebral block(TPVB)or sufentanil(SUF)-based multimodal ***,the efficacy and impact of their combined use on postoperative pain and postoperative cognitive dysfunction(POCD)remain *** To explore the analgesic effect and the influence on POCD of TPVB combined with SUF-based multimodal analgesia in patients undergoing thoracoscopic radical resection for LC to help optimize postoperative pain management and improve patient *** This retrospective analysis included 107 patients undergoing thoracoscopic radical resection for LC at The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital between May 2021 and January *** receiving SUF-based multimodal analgesia(n=50)and patients receiving TPVB+SUF-based multimodal analgesia(n=57)were assigned to the control group and TPVB group,*** compared the Ramsay Sedation Scale and visual analog scale(VAS)scores at rest and with cough between the two groups at 2,12,and 24 h after *** levels of epinephrine(E),angio-tensin Ⅱ(Ang Ⅱ),norepinephrine(nE),superoxide dismutase(SOD),vascular endothelial growth factor(VEGF),transforming growth factor-β1(TGF-β1),tumor necrosis factor-α(TnF-α),and S-100 calcium-binding proteinβ(S-100β)were measured before and 24 h after *** Mini-Mental State Examination(MMSE)was administered 1 day before surgery and at 3 and 5 days after surgery,and the occurrence of POCD was monitored for 5 days after *** reactions were also *** There were no significant time point,between-group,and interaction effects in Ramsay sedation scores between the two groups(P>0.05).Significantly,there were notable time point effects,between-group differences,and interaction effects observed in VAS scores both at rest

关键词： Thoracic paravertebral block Sufentanil Thoracoscope Radical resection of lung cancer Postoperative cognitive dysfunction

Two Indium(III)-based Fluorescent Metal-Organic Frameworks for Highly Sensing Fe^(3+),2,4-DnP,and TnP

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Chemical Research in Chinese Universities 2024年第1期40卷 119-126页

作者： WAnG dan LI Wen LI Guanghua HUA Jia LIU Yunling State Key Laboratory of Inorganic Synthesis&Preparative Chemistry Jilin UniversityChangchun130012P.R.China

Two novel metal-organic frameworks(MOFs),JLU-MOF130([In(nH2−BDC)(Imi)(1H−Imi)]·DMF·H2O,nH2−H2BDC=2-aminobenzene-1,4-dicarboxylic acid,1H−Imi=1H-imidazole,DMF=n,n-dimethylformamide)and JLU-MOF131([In(1,4-nDC)(Imi)(1H−Imi)]·DMF0.5,1,4-H_(2)nDC=1,4-naphthalene-dicarboxylic acid),were ***-MOF130 features a three-dimensional(3D)architecture with a neb ***-MOF131 is characterized by a two-dimensional(2D)structure with an sql ***-MOF130 has excellent fluorescence detection performance towards Fe^(3+),2,4-dinitrophenol(2,4-DnP),and 2,4,6-trinitrophenol(TnP),but the fluorescence detection performance of JLU-MOF131 is further improved by converting nH2−H2BDC to more conjugated 1,4-H_(2)*** Stern-Volmer(SV)quenching constant(KSV)values of JLU-MOF130 sensing 2,4-DnP,TnP,and Fe^(3+)are 5.24×10^(4),4.44×10^(4),and 4.73×10^(3) L/mol,*** corresponding limit of detection(LOD)values are 1.17,1.36,and 14.59µmol/*** KSV values for JLU-MOF131 are 1.26×10^(5),9.02×10^(4),and 8.48×103 L/mol,and the corresponding LOD values are 0.35,0.42,and 3.60µmol/L,***,the emission wavelengths of the two MOFs obviously shift as the fluorescence emission intensities decrease upon the addition of 2,4-DnP and TnP,which can be applied in selective detection.

关键词： Metal-organic framework Fluorescence quenching Fe^(3+) 2 4-Dinitrophenol(2 4-DnP) 2 4 6-Trinitrophenol(TnP)

Security-constrained Transmission Maintenance Optimization Considering Generation and Operational Risk Costs

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 767-781页

作者： dan Xu Zhi Cai Qian Cheng Guodong Huang Jingyang Zhou Junjie Tang Beijing Key Laboratory of Research and System Evaluation of Power Dispatching Automation Technology China Electric Power Research InstituteBeijing 100192China State Key Laboratory of Power Transmission Equipment&System Security and new Technology Chongqing UniversityChongqing 400044China

With the large-scale integration of renewable energy,the traditional maintenance arrangement during the load valley period cannot satisfy the transmission demand of renewable energy ***,in a market-oriented operation mode,the power dispatching control center aims to reduce the overall power purchase cost while ensuring the security of the power ***,a security-constrained transmission maintenance optimization model considering generation and operational risk costs is proposed *** model is built on double-layer optimization framework,where the upper-layer model is used for maintenance and generation planning,and the lowerlayer model is primarily used to address the operational security risk arising from the random prediction error and n-1 transmission ***,a generation-maintenance iterative algorithm based on a defined cost feedback is included to increase solution *** cost is determined using long-term security-constrained unit commitment,and the operational risk cost is obtained using a double-layer n-1 risk assessment *** electrical correlation coupling coefficient is proposed for the solution process to avoid maintenance of associated equipment simultaneously,thereby improving model convergence *** IEEE 118-bus system is used as a test case for illustration,and test results suggest that the proposed model and algorithm can reduce the total cost of transmission maintenance and system operation while effectively improving the solution efficiency of the joint optimization model.

关键词： Transmission maintenance security-constrained unit commitment iterative algorithm cost feedback n−1 risk assessment

Fluidization stability and periodic fluctuations in gas–solid separation fluidized bed using Geldart A den.e medium

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Particuology 2024年第7期90卷 522-534页

作者： Weijin Liu dan Wang Liang Dong Enhui Zhou Tatiana Aleksandrova Chenyang Zhou Chenlong Duan Key Laboratory of Coal Processing and Efficient Utilization(China University of Mining&Technology) Ministry of EducationXuzhou 221116China School of Chemical Engineering&Technology China University of Mining&TechnologyXuzhou 221116China Department of Chemical and Biochemical Engineering The University of Western OntarioLondonOntario N6A 5B9Canada Mineral Processing Department Saint Petersburg Mining UniversitySt.Petersburg 199106Russia

Gas–solid separation fluidized bed is a typical method for coal separation without water *** A particles is also considered as the ideal den.e medium to strengthen separation *** stability reflects the bed pressure fluctuations and the distribution of bubble and emulsion phases,affecting the separation *** the main frequency of pressure fluctuations can directly reflect the degree of pressure ***,the detailed fluidization stability is analyzed combined the method of standard deviation of pressure fluctuations,power spectral den.ity,etc.,for Geldart A *** results showed that maintaining an appropriate gas velocity resulted in an average bed pressure of around 2000 *** main frequency is mainly concentrated around 1–1.5 ***,a prediction model of the main frequency of pressure fluctuations is established,and the error can be controlled within±*** investigation further proved the stable fluidization of Geldart A particles and provides a method for predicting the main frequency of pressure fluctuations in the gas–solid separation fluidized bed.

关键词： Geldart A den.e medium Fluidization stability Periodic fluctuations Pressure fluctuations frequency Gas–solid separation fluidized bed

Phosphine-catalyzed acyl-transfer of heteroaryl ketones for the construction of n-fused heterocycles

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Chinese Chemical Letters 2024年第3期35卷 252-256页

作者： Yu Zhang De-Rui Han dan Ye Hong Lu Hao Wei Key Laboratory of Synthetic and natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of n-containing heteroaryl ketones for the rapid synthesis of n-fused *** key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C *** using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of n-containing heteroaryl ketones allows a streamlined assembly of complex n-fused heterocycles with broad functional group tolerance.

关键词： Phosphine catalysis Acyl-transfer n-Fused heterocycles C–C bond activation Aromatization

Clean air captures attention whereas pollution distracts:eviden.e from brain activities

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 5-15页

作者： Jianxun Yang Yunqi Liu Berry van den.Berg Susie Wang Lele Chen Miaomiao Liu Jun Bi State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET) Nanjing University of Information Science&TechnologyNanjing 210044China nanjing Foreign Language School Nanjing 210008China Department of Experimental Psychology University of GroningenGrote Kruisstraat 2/19712 TSGroningenThe Netherlands Department of Social Psychology University of GroningenGrote Kruisstraat 2/19712 TSGroningenThe Netherlands School of Education Science Nantong UniversityNantong 226019China

Awareness of the adverse impact of air pollution on attention-related performance such as learning and driving is rapidly ***,there is still little known about the underlying neurocognitive *** an adapted dot-probe task paradigm and event-related potential(ERP)technique,we investigated how visual stimuli of air pollution influence the attentional allocation *** were required to make responses to the onset of a target presented at the left or right visual *** probable location of the target was forewarned by a cue(pollution or clean air images),appearing at either the target location(attention-holding trials)or the opposite location(attention-shifting trials).Behavioral measures showed that when cued by pollution images,subjects had higher response accuracy in attention-shifting *** analysis results revealed that after the cue onset,pollution images evoked lower n300 amplitudes,indicating less attentioncapturing effects of dirty *** the target onset,pollution cues were correlated with the higher P300 amplitudes in attention-holding trials but lower amplitudes in attention-shifting *** indicates that after visual exposure to air pollution,people need more neurocognitive resources to maintain attention but less effort to shift attention *** findings provide the first neuroscientific eviden.e for the distracting effect of air *** conclude with several practical implications and suggest the ERP technique as a promising tool to understand human responses to environmental stressors.

关键词： Air pollution Attention Disengagement Performance Event-related potential