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Global Zero-relaxation Limit Problem of the Electro-diffusion Model Arising in Electro-Hydrodynamics

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 241-268页

作者： ming-hua Yang Si-ming Huang Jin-yi sun Department of Mathematics Jiangxi University of Finance and EconomicsNanchang330032China School of Public Administration Guangdong University of Foreign StudiesGuangzhou510006China College of Mathematics and Statistics Northwest Normal UniversityLanzhou730070China

In this paper,we study a global zero-relaxation limit problem of the electro-diffusion model arising in electro-hydrodynamics which is the coupled Planck-Nernst-Poisson and Navier-Stokes *** is,the paper deals with a singular limit problem of{u^(∈)_(t)+u^(∈)·▽u^(∈)-Δu^(∈)+▽P^(∈)=Δφ^(∈)▽φ^(∈),in R^(3)×(0,∞),▽·u^(∈)=0,in R^(3)×(0,∞),n^(∈)_(t)+u^(∈)·▽n^(∈)-Δn^(∈)=-▽·(n^(∈)▽φ^(∈)),in R^(3)×(0,∞),ct+u^(∈)·▽c^(∈)-Δc^(∈)=▽·(c^(∈)▽φ^(∈)),in R^(3)×(0,∞),∈^(-1)φ^(∈)_(t)=Δφ^(∈)-n^(∈)+c^(∈),in R^(3)×(0,∞),(u^(∈),n^(∈),c^(∈),φ^(∈))|t=0=(u0,n0,c0,φ0),in R^(3) involving with a positive,large parameter^(∈).The present work show a case that(u^(∈),n^(∈),c^(∈))stabilizes to(u^(∞),n∞,c∞):=(u,n,c)uniformly with respect to the time variable as^(∈)→+∞with respect to the strong topology in a certain Fourier-Herz space.

关键词： fourier-Herz space littlewood-Paley decomposition stability limit dissipative system

Control of 2-D Semi-Markov Jump Systems:A View from Mode Generation Mechanism

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 258-260页

作者： Yunzhe Men Jian sun jie Chen the National Key Laboratory of Autonomous Intelligent Unmanned Systems the School of AutomationBeijing Institute of TechnologyBeijing 100081 the Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China the Department of Control Science and Engineering Tongji UniversityShanghai 201804 the National Key Laboratory of Autonomous Intelligent Unmanned Systems Beijing Institute of TechnologyBeijing 100081China

Dear Editor,Two-dimensional(2-D) systems have wide applications in image data processing,gas absorption and fluid dynamics analysis [1]-[3].When there exist abrupt changes in 2-D systems,they are usually modeled by 2-D Markov jump systems(MJSs) or 2-D semi-Markov jump systems(SMJSs).This letter investigates the control of 2-D SMJSs based on a novel mode generation mechanism,which could avoid mode ambiguousness phenomenon caused by the evolution of system mode in two different *** criterion that guarantees the almost surely exponential stability of the system is obtained.A thermal process is studied to demonstrate the availability of the proposed method.

关键词： Markov mode system

Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-Xiu Shi Yi-ming Ou Hua-jie Jiang Yi-Jun Fang Qi-ming Wang Quan Gao jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

Effect of wire mesh casing treatment on axial compressor performance and stability

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Chinese Journal of Aeronautics 2024年第3期37卷 60-76页

作者： ming ZHANG Jiaming ZHANG Jiahao HU Xu DONG Dakun sun Xiaofeng sun School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China

In this paper,a kind of Wire Mesh Casing Treatment(WMCT)is proposed to improve the stable operating range of the *** contrast to the traditional circumferential groove,as for WMCT,a layer of wire mesh is laid on the surface of the circumferential *** studies were conducted on the low-speed axial flow compressor,including the groove width,axial location,and mesh *** optimum axial location for WMCT is related to its groove width.A higher wire mesh count results in a smaller compressor stall margin *** simulations were carried out to study the effect of WMCT on the flow structure of the *** wire mesh in the WMCT has a certain flow resistance,which restricts the flow into and out of the *** to the WMCT,the flow parameter in the tip region of the rotor is less sensitive to changes in the operating conditions of the *** WMCT causes the rotor tip blade loading to shift backward,inhibiting the formation of spill forward of the leakage flow,and thus improving the stability of the *** flow resistance on the groove surface is a new degree-of-freedom for the casing treatment designer.

关键词： Axial compressor Wire mesh casing treatment Tip clearance flow Stall margin Blade loading

Effective Activation of Melamine for Synchronous Synthesis of Catalytically Active Nanosheets and Fluorescence-Responsive Quantum Dots

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Transactions of Tianjin University 2024年第3期30卷 284-296页

作者： jie Xuan Guijian Guan ming-Yong Han Institute of Molecular Plus Tianjin UniversityTianjin 300072China

Because of the low reactivity of cyclic nitrides,liquid-phase synthesis of carbon nitride introduces challenges despite its favorable potential for energy-efficient preparation and superior *** this study,we demonstrate a strong interaction between citric acid and melamine through experimental observation and theoretical simulation,which eff ectively activates melamine-condensation activity and produces carbon-rich carbon nitride nanosheets(CCN NSs)during hydrothermal *** a large specific surface area and increased light absorption,these CCN NSs demonstrate significantly enhanced photocatalytic activity in CO_(2) reduction,increasing the CO production rate by approximately tenfold compared with hexagonal melamine(h-Me).Moreover,the product selectivity of CCN NSs reaches up to 93.5%to generate CO from CO_(2).Furthermore,the annealed CCN NSs exhibit a CO conversion rate of up to 95.30μmol/(g h),which indicates an 18-fold increase compared with traditional carbon *** the CCN NS synthesis,nitrogen-doped carbon quantum dots(NDC QDs)are simultaneously produced and remain suspended in the supernatant after *** QDs disperse well in water and exhibit excellent luminescent properties(QY=67.2%),allowing their application in the design of selective and sensitive sensors to detect pollutants such as pesticide 2,4-dichlorophenol with a detection limit of as low as 0.04μmol/***,the simultaneous synthesis of CCN NSs and NDC QDs provides a cost-eff ective and highly efficient process,yielding products with superior capabilities for catalytic conversion of CO_(2) and pollutant detection,respectively.

关键词： Carbon nitride Hydrothermal reaction Photocatalysis Carbon dioxide Quantum dots

Computed tomography radiomic features and clinical factors predicting the response to first transarterial chemoembolization in intermediate-stage hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 361-369页

作者： Zhong-Xing Shi Chang-Fu Li Li-Feng Zhao Zhong-Qi sun Li-ming Cui Yan-jie Xin Dong-Qing Wang Tan-Rong Kang Hui-jie Jiang Department of Interventional Radiology the Second Affiliated Hospital of Harbin Medical UniversityHarbin 150086China Department of Digestive Medicine Daqing Longnan HospitalDaqing 163453China Department of Radiology Daqing Longnan HospitalDaqing 163453China Department of Radiology the Second Affiliated Hospital of Harbin Medical UniversityHarbin 150086China

Background:According to clinical practice guidelines,transarterial chemoembolization(TACE)is the standard treatment modality for patients with intermediate-stage hepatocellular carcinoma(HCC).Early prediction of treatment response can help patients choose a reasonable treatment *** study aimed to investigate the value of the radiomic-clinical model in predicting the efficacy of the first TACE treatment for HCC to prolong patient ***:A total of 164 patients with HCC who underwent the first TACE from January 2017 to September 2021 were *** tumor response was assessed by modified response evaluation criteria in solid tumors(mRECIST),and the response of the first TACE to each session and its correlation with overall survival were *** radiomic signatures associated with the treatment response were identified by the least absolute shrinkage and selection operator(LASSO),and four machine learning models were built with different types of regions of interest(ROIs)(tumor and corresponding tissues)and the model with the best performance was *** predictive performance was assessed with receiver operating characteristic(ROC)curves and calibration ***:Of all the models,the random forest(RF)model with peritumor(+10 mm)radiomic signatures had the best performance[area under ROC curve(AUC)=0.964 in the training cohort,AUC=0.949 in the validation cohort].The RF model was used to calculate the radiomic score(Rad-score),and the optimal cutoff value(0.34)was calculated according to the Youden’s *** were then divided into a high-risk group(Rad-score>0.34)and a low-risk group(Rad-score≤0.34),and a nomogram model was successfully established to predict treatment *** predicted treatment response also allowed for significant discrimination of Kaplan-Meier *** Cox regression identified six independent prognostic factors for overall survival,including male[hazard ratio(HR)=0.500,95%confidence interva

关键词： Hepatocellular carcinoma Transarterial chemoembolization Radiomics Treatment response Prediction

Lithium Chloride Inhibited Neuronal Apoptosis and Glycogen Synthase Kinase -3β Activities in Hippocampal CA1 Area After Middle Cerebral Artery Occlusion and Reperfusion in Rats

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麻醉与监护论坛 2011年第1期18卷 43-48页

作者： Xin-heWang Qing-ming Bian jie sun Yan-ning Qian Department of Anesthesiology The First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China

Background: Lithium pretreatment has been proved to be neuro-protective. Post-ischemia conditioning attracted more and more attention during the last years. This study was designed to observe the effect of lithium post-treatment on neuron apoptosis and glycogen synthase kinase(GSK)-3βin rats after middle cerebral artery occlusion(MCAO). Methods: The right middle cerebral artery was occluded with a nylon suture for 90 mins. Rats were randomly divided into NO group, SH group, IR group, Lil group (lmmol/kg) , Li2 group (2mmol/kg) , and Li3 group (3mmol/kg) . Animals in each group were killed 6 hours, 1 day, 3day, or 7days after cerebral ischemia, with six rats in each time point. Neuron apoptosis in the CA 1 region were examined by Hoechst staining. The expression and distribution of GSK-3βand p-GSK-3β(Ser9) was examined by immunofluorescence analysis. Results: The apoptotic nuclei was detected significantly in IR groups compared with SH group(P0.01). The amounts of P-GSK-3β(Ser9) seemed increased with the time and they were higher in IR groups than those in SH groups (P<0.01). Lithium post-treatment reinforced this tendency dose-dependently (P<0.01).Conclusion: Lithium chloride can dose-dependently (1 -3 mmol/kg) suppress neuron apoptosis and GSK-3βafler MCAO/reperfusion injury.

关键词：神经系统大脑动脉医学研究

An approach for determination of lateral limit angle in kinematic planar sliding analysis for rock slopes

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1305-1314页

作者： Xiaojuan Yang jie Hu Honglei sun Jun Zheng College of Civil Engineering Zhejiang University of TechnologyHangzhou310023China Department of Civil Engineering Zhejiang UniversityHangzhou310058China Center for Balance Architecture Zhejiang UniversityHangzhou310007China The Architectural Design & Research Institute of Zhejiang University Co. Ltd.Hangzhou310063China

Planar sliding is one of the frequently observed types of failure in rock *** analysis is a classic and widely used method to examine the potential failure modes in rock *** accuracy of planar sliding kinematic analysis is significantly influenced by the value assigned to the lateral limit angleγ***,the assignment ofγlim is currently used generally based on an empirical *** study aims to propose an approach for determining the value ofγlim in deterministic and probabilistic kinematic planar sliding analysis.A new perspective is presented to reveal thatγlim essentially influences the probability of forming a potential planar sliding *** procedure to calculate this probability is introduced using the block theory *** is found that the probability is correlated with the number of discontinuity sets presented in rock ***,different values ofγlim for rock masses with different sets of discontinuities are recommended in both probabilistic and deterministic planar sliding kinematic analyses;whereas a fixed value ofγlim is commonly assigned to different types of rock masses in traditional ***,an engineering case was used to compare the proposed and traditional kinematic analysis *** error rates of the traditional method vary from 45%to 119%,while that of the proposed method ranges between 1%and 17%.Therefore,it is likely that the proposed method is superior to the traditional one.

关键词： Kinematic analysis Block theory Planar sliding Lateral limit angle Rock slope

Consolidation of high replacement ratio stone column-reinforced ground:Analytical solutions incorporating clogging effect

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3311-3326页

作者： Jinxin sun Mengmeng Lu Baolong Xu jie Shan School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou221116China Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221006China

The utilization of stone columns has emerged as a popular ground improvement strategy,whereas the drainage performance can be adversely hampered by clogging *** the ample progress of calculation methods for the consolidation of stone column-improved ground,theoretical investigations into the clogging effect have not been thoroughly ***,it is imperative to involve the column consolidation deformation to mitigate computational error on the consolidation of composite ground with high replacement *** this context,an analytical model accounting for the initial clogging and coupled time and depth-dependent clogging of stone columns is ***,the resulting governing equations and analytical solutions are obtained under a new flow continuity relationship to incorporate column consolidation *** accuracy and reliability of the proposed model are illustrated by degradation analysis and case studies with good ***,the computed results of the current study are juxtaposed against the existing models,and an in-depth assessment of the impacts of several crucial parameters on the consolidation behavior is *** results reveal that ignoring column consolidation deformation leads to an overestimate of the consolidation rate,with maximum error reaching up to 16%as the replacement ratio ***,the initial clogging also has a significant influence on the consolidation ***,the increment of depth and time-clogging factors a and b will induce a noticeable retardation of the consolidation process,particularly in the later stage.

关键词： Consolidation Composite ground Stone column Clogging effect Ground improvement Analytical model