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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 550-570页

作者： Ya-jie li Hao-kun QI Zheng-bo CHANG Xin-zhu MENG College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China Weifang Commercial College of Shandong Weifang 261011China College of Mathematics and Information Science Anshan Normal UniversityAnshan 114007China

This paper investigates the stochastic dynamics of trophic cascade chemostat model perturbed by regime switching, Gaussian white noise and impulsive toxicant input. For the system with only white noise interference, sufficient conditions for stochastically ultimate boundedness and stochastically permanence are obtained, and we demonstrate that the stochastic system has at least one nontrivial positive periodic solution. For the system with Markov regime switching, sufficient conditions for extinction of the microorganisms are established. Then we prove the system is ergodic and has a stationary distribution. The results show that both impulsive toxins input and stochastic noise have great effects on the survival and extinction of the microorganisms. Finally, a series of numerical simulations are presented to illustrate the theoretical analysis.

关键词： stochastic trophic cascade chemostat model Markov chain extinction and stochastic permanence periodic solution ergodicity

Fixturing technology and system for thin-walled parts machining:a review

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Frontiers of Mechanical Engineering 2022年第4期17卷 1-32页

作者： Haibo liU Chengxin WANG Te li Qile bo Kuo liU Yongqing WANG Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China

During the overall processing of thin-walled parts(TWPs),the guaranteed capability of the machining process and quality is determined by ***,reliable fixtures suitable for the structure and machining process of TWP are *** this review,the key role of fixtures in the manufacturing system is initially *** main problems in machining and workholding due to the characteristics of TWP are then analyzed in ***,the definition of TWP fixtures is reinterpreted from narrow and broad *** functions corresponding to the issues of machining and workholding are then clearly *** categories are classified systematically according to previous research achievements,and the operation mode,functional characteristics,and structure of each fixture are comprehensively *** function and execution mode of TWP fixtures are then systematically summarized and analyzed,and the functions of various TWP fixtures are *** directions for future research on TWP fixtures technology are also *** main purpose of this review is to provide some reference and guidance for scholars to examine TWP fixtures.

关键词： thin-walled part(TWP) fixture machining fixture categories fixture function

Prediction study of hydrocarbon reservoir based on time-frequency domain electromagnetic technique taking Ili Basin as an example

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Applied Geophysics 2020年第5期17卷 687-699,900,901页

作者： Tian Yu-Kun Zhou Hui Ma yan-yan li Juan The Key Laboratory of unconventional oil and gas geology Oil and Gas resources Survey CenterChina Geological SurveyBeijing 100083China

The time-frequency domain electromagnetic(TFEM)sounding technique can directly detect oil and gas characteristics through anomalies in resistivity and *** recent years,it has made some breakthroughs in hydrocarbon *** was applied to predict the petroliferous property of the Ili *** accordance with the geological structure characteristics of the study area,a two-dimensional layered medium model was constructed and forward modeling was *** used the forward-modeling results to guide fi eld construction and ensure the quality of the fi eld data *** used the model inversion results to identify and distinguish the resolution of the geoelectric information and provide a reliable basis for data *** the basis of our results,key technologies such as 2D resistivity tomography imaging inversion and polarimetric constrained inversion were developed,and we obtained abundant geological and geophysical *** characteristics of the TFEM anomalies of the hydrocarbon reservoirs in the Ili Basin were summarized through an analysis of the electrical logging data in the study ***,the oil-gas properties of the Permian and Triassic layers were predicted,and the next favorable exploration targets were optimized.

关键词： Time–Frequency Domain Electromagnetic Hydrocarbon Detection Polarizability Anomaly Favorable Area Prediction

Enhanced Upconversion Emissions of TiO_(2):Yb^(3+)/Tm^(3+) Nanocrystals: Comparison with Different Effects of li^(+),Mn^(2+) and Cu^(2+) Ions

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1379-1384页

作者： JI He-Ming XU Ming-Guang ZHANG Hai-yan li Xiao-Long QIAN yan-Nan Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006China School of Mechanical and Electrical Engineering Yunnan Agricultural UniversityKunming 650201China

Codoping with M^(n+) ions (M^(n+)=li^(+),Mn^(2+) and Cu^(2+)) enhanced the blue and red upconversion (UC)emissions in TiO_(2):Yb^(3+)/Tm^(3+) nanocrystals under 980 nm *** different effects of li^(+),Mn^(2+) and Cu^(2+) ions on the phase structures,morphologies and optical characteristics of TiO_(2):Yb^(3+)/Tm^(3+)were *** minor shifting in the diffraction peaks at 25.2°was observed for TiO_(2):Yb^(3+)/Tm^(3+)/li^(+),and adding Mn^(2+) ions remained almost the same position of diffraction peaks,while the introduction of Cu^(2+) ions resulted in the shift of the diffraction peaks towards the larger ***_(2):Yb^(3+)/Tm^(3+)/li^(+)and TiO_(2):Yb^(3+)/Tm^(3+)/Mn^(2+) nanosheets and the sphere-like TiO_(2):Yb^(3+)/Tm^(3+)/Cu^(2+) were *** mechanisms for increased UC emissions caused by adding li^(+),Mn^(2+) and Cu^(2+) ions were attributed to the tailored local environment around Tm^(3+) ions,efficient energy transition between Mn^(2+) -Yb^(3+) dimer and Tm^(3+) ions,and the localized surface plasmon resonance (LSPR) of Cu^(2+) ions,respectively.

关键词： TiO_(2):Yb^(3+)/Tm^(3+) li^(+) Mn^(2+)and Cu^(2+) optical characteristics

Continuum Skyrme Hartree-Fock-bogoliubov theory with Green’s function method for neutron-rich Ca,Ni,Zr,and Sn isotopes

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Nuclear Science and Techniques 2023年第7期34卷 162-178页

作者： En-bo Huo Ke-Ran li Xiao-Ying Qu Ying Zhang Ting-Ting Sun School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China School of Mechatronics Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Physics School of ScienceTianjin UniversityTianjin 300072China Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China

The possible exotic nuclear properties in the neutron-rich Ca,Ni,Zr,and Sn isotopes are examined with the continuum Skyrme Hartree-Fock-bogoliubov theory in the framework of the Green’s function *** pairing correlation,the couplings with the continuum,and the blocking effects for the unpaired nucleon in odd-A nuclei are properly *** Skyrme interaction SLy4 is adopted for the ph channel and the density-dependentinteraction is adopted for the pp chan-nel,which well reproduce the experimental two-neutron separation energies S_(2n)and one-neutron separation energies *** is found that the criterion S_(n)>0 predicts a neutron drip line with neutron numbers much smaller than those for S_(2n)>*** to the unpaired odd neutron,the neutron pairing energies−E_(pair)in odd-A nuclei are much lower than those in the neighbor-ing even-even *** investigating the single-particle structures,the possible halo structures in the neutron-rich Ca,Ni,and Sn isotopes are predicted,where sharp increases in the root-mean-square(rms)radii with significant deviations from the traditional rA^(1∕3)rule and diffuse spatial density distributions are *** the contributions of various partial waves to the total neutron densityρlj(r)∕ρ(r)reveals that the orbitals located around the Fermi surface-particularly those with small angular momenta-significantly affect the extended nuclear density and large rms *** number of neutrons Nλ(N_(0))occupying above the Fermi surfacen(continuum threshold)is discussed,whose evolution as a function of the mass number A in each isotope is consistent with that of the pairing energy,supporting the key role of the pairing correlation in halo phenomena.

关键词： Neutron-rich nuclei Neutron halo Skyrme Hartree-Fock-bogoliubov theory Green’s function method

Photoluminescence Studies of Single Submonolayer InAs Structures Grown on GaAs (001) Matrix

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Chinese Physics Letters 1995年第11期12卷 697-700页

作者： li Wei WANG Zhanguo liANG Jiben XU bo ZHU Zhanping YUAN Zhiliang li Jian Laboratory of Semiconductor Materials Science Institute of SemiconductorsAcademia SinicaBeijing 100083 National Semiconductor Superlattice Laboratory Institute of SemiconductorsAcademia SinicaBeijing 100083 National Integrated Optoelectronics Laboratory Institute of SemiconductorsAcademia SinicaBeijing 100083

We report a detailed analysis of optical properties of single submonolayer InAs structures grown on GaAs(001)*** is shown that the formation of InAs dots with 1 monolayer(ML)height leads to localization of exciton under certain submonolayer InAs coverage,which play a key role in the highly improved luminescence efficiency of the submonolayer InAs/GaAs structures.

关键词： InAs/GaAs InAs monolayer

Corrosion fatigue behavior of epoxy-coated Mg–3Al–1Zn alloy in NaCl solution

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Rare Metals 2014年第3期33卷 276-286页

作者： Xiu-li He Ying-Hui Wei li-Feng Hou Zhi-Feng yan Chun-li Guo Peng-Ju Han College of Materials Science and Engineering Taiyuan University of Technology Department of Chemistry Luliang College

The corrosion fatigue behavior of epoxy-coated Mg-3Al-1Zn alloy was investigated in air and 3.5 wt%NaCl solution. Epoxy coating as a new method was used to improve the corrosion fatigue property of the *** show that the fatigue limit（FL） of the coated specimens is higher than that of the uncoated specimens in3.5 wt% NaCl solution because of the strengthening and blocking functions of the epoxy coating. The FL of the coated specimens in 3.5 wt% NaCl solution is as high as that in air. It implies that the coated specimens are not as sensitive to the environment as the magnesium alloy. The low tensile strength and the short elongation of the pure epoxy coating lead to that the fatigue crack of the coated specimen is always initiated from the epoxy-coating film Pores and pinholes accelerate the fatigue crack initiation process. Pinholes are caused by the corrosion reactions between the epoxy coating and the NaCl solution.

关键词： Epoxy coating Corrosion fatigue Magnesium alloy 3.5 wt% NaCl solution FatigueCrack initiation

A Causal Configuration Analysis of Payment Decision Drivers in Paid Q&A

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Journal of Data and Information Science 2021年第2期6卷 139-162页

作者： Wenyu Chen yan Cheng Jia li School of Business East China University of Science and TechnologyShanghai 200237China

Purpose:This paper examines factors of payment decision as well as the role each factor plays in casual configurations leading to high payment intention under systematic and heuristic information processing ***/methodology/approach:Based on heuristic-systematic model(HSM),we propose a configurational analytic framework to investigate complex casual relationships between influencing factors and payment *** line with this approach,we use fuzzy-set qualitative comparative analysis(fsQCA)to analyze data crawled from ***:The number of previous consultations is a necessary element in all five equivalent configurations which lead to high intention in payment *** heuristic processing route plays a core role while the systematic processing route plays a peripheral role in payment decision-making *** limitations:Research is limited in that moderating effect of professional fields has not been considered in the *** implications:Configurations in results can assist managers of knowledge communities and paid Q&A service providers in the management of information elements to motivate more payment ***/value:This paper is one of the few studies to apply HSM theory and fsQCA method with respect to the payment decision in paid Q&A.

关键词： Payment decision Paid Q&A Dual-process theory Configurational paradigm Fuzzy-set qualitative comparative analysis(fsQCA)

The role of transcriptional factor D-site-binding protein in circadian CCL2 gene expression in anti-Thy1 nephritis

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Cellular & Molecular Immunology 2019年第9期16卷 735-745页

作者： yang Lu yan Mei Lei Chen lingling Wu Xu Wang Yingjie Zhang bo Fu Xizhao Chen Yuansheng Xie Guangyan Cai Xueyuan Bai Qinggang li Xiangmei Chen Department of Nephrology Chinese PLA General HospitalChinese PLA Institute of NephrologyState Key Laboratory of Kidney DiseasesNational Clinical Research Center for Kidney DiseasesBeijingChina

Mesangial proliferative glomerulonephritis(MsPGN)is an inflammatory disease,but both the nature of disease progression and its regulation remain *** the present study,we monitored the course of anti-Thy1 nephritis from days 1 to 5 and established gene expression profiles at each time point using microarrays to explore the development of *** to the gene expression profiles,macrophage infiltration(triggered by CCL2 activation)was evident on day 1 and enhanced inflammation over the next few *** screened for genes with expression levels similar to CCL2 and found that the upregulation of the circadian gene albumin D-site-binding protein(DBP)was involved in CCL2 activation in mesangial *** importantly,CCL2 expression showed oscillatory changes similar to DBP,and DBP induced peak CCL2 expression at 16:00 a clock on day 1 in the anti-Thy1 nephritis *** knocked down DBP through transfection with a small interfering RNA(siRNA)and used RNA sequencing to identify the DBP-regulated TNF-α-CCL2 *** performed chromatin immunoprecipitation sequencing(ChIP-Seq)and the dual luciferase assay to show that DBP bound to the TRIM55 promoter,regulating gene expression and in turn controlling the TNF-α-CCL2 *** conclusion,DBP-regulated circadian CCL2 expression by the TRIM55-TNF pathway in injured mesangial cells at an early stage,which promoted macrophage recruitment and in turn triggered infiltration and inflammation in a model of anti-Thy1 nephritis.

关键词： Mesangial proliferative glomerulonephritis DBP CCL2 Trim 55 Macrophage

Shenweifang-containing serum inhibits transforming growth factor-β1–induced myofibroblast differentiation in normal rat kidney interstitial fibroblast cells

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Journal of Traditional Chinese Medicine 2022年第1期42卷 39-48页

作者： liN Jiaru WANG li CHEN bo OU Santao QIN Jianhua FAN Junming Department of Nephrology the Affiliated Hospital of Southwest Medical UniversityLuzhou 646000China Nephropathy Clinical Medical Research Center of Sichuan Province Luzhou 646000China Chengdu University of Traditional Chinese Medicine Chengdu 610075China Central Laboratory the Affiliated Chinese Medicine Hospital of Southwest Medical UniversityLuzhou 646000China Central Laboratory Affiliated Chinese Medicine Hospital of Southwest Medical UniversityLuzhouSichuan 646000China Chengdu Medical College ChengduSichuan 610500China Southwest Medical University Luzhou 646000China

OBJECTIVE:To investigate the efficacy of Shenweifang(SWF)-containing serum on transforming growth factor(TGF)-β1–induced fibroblast-myofibroblast transition in normal rat kidney interstitial fibroblast cells(NRK-49 F).METHODS:Sprague-Dawley rats were gavaged with one of five solutions:(a)saline;(b)saline plus low-dose SWF;(c)saline plus medium-dose SWF;(d)saline plus highdose SWF;and(e)saline plus ***-49 F cells were treated with TGF-β1 and cultured using serum from the gavaged ***:TGF-β1 treatment increased the expression ofα-smooth muscle actin,proliferating cell nuclear antigen,collagenⅠ,Smad3,mitogen-activated protein kinase(MAPK)10,and c-Jun N-terminal kinase(JNK)3 and induced abnormalities in cell morphology,cell cycle progression,and cell ***:SWF-or valsartan-containing serum corrected(or partially corrected)TGF-β1–induced abnormal changes in this in vitro ***-containing serum reversed abnormalities in morphology,cell cycle progression,and proliferation in TGF-β1–treated NRK-49F cells,probably by blocking the TGF-β1/Smads and TGF-β1/MAPK/JNK pathways.

关键词： fibrosis transforming growth factor beta1 Smad proteins mitogen-activated protein kinases JNK mitogen-activated protein kinases drug-containing serum Shenweifang