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lie Point Symmetries and Exact Solutions of Couple KdV Equations

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Communications in Theoretical Physics 2007年第4期47卷 582-586页

The simple lie point symmetry reduction procedure is used to obtain infinitely many symmetries to a new integrable system of coupled KdV equations. Using some symmetry subalgebra of the equations, five types of the significant similarity reductions are obtained by virtue of the lie group approach, and obtain abundant solutions of the coupled KdV equations, such as the solitary wave solution, exponential solution, rational solution, polynomial solution, etc.

关键词： coupled KdV equations lie point symmetry exact solutions

Laser cladding of Ni-based alloy on stainless steel

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 296-300页

作者： XUE Chun-fang tian xin-li TAN Yong-sheng WU Zhi-yuan Department of Mechanical Engineering Academy of Armored Force Engineering Beijing 100072 China Department of Mechanical Engineering Academy of Armored Force Engineering Beijing 100072 China Key Laboratory for High Energy Density Beam Processing TechnologyGeneral Company of Aeronautics Industry Beijing 100024 China Department of Mechanical Engineering Academy of Armored Force Engineering Beijing 100072 China

The coatings on a stainless steel substrate were conducted by laser cladding of Ni-based alloy, using a 5 kW continuous wave CO2 flow transverse laser. SEM, EDX and X-ray diffraction were used to analyze the microstructure and constituent phases of the obtained coatings by laser cladding with direct injection of the powder into the melt pool. Solidification planar, cellular and dendrite structures were observed in Ni-based alloy coating. There exists an optimum metallurgical bond between Ni-based laser cladding layer and the base material. The high hardness of the Ni-based alloy coating is attributed to the presence of M7C3-type carbides (essentially chromium-riched carbide) dispersed in the γ(Ni,Fe) phase matrix.

关键词： laser cladding Ni-based alloy microstructure

One-pot synthesis of network supported catalyst using supramolecular gel as template

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Chinese Chemical Letters 2010年第8期21卷 991-994页

作者： Yong liang li Ming Tang Yu Xia Kai Chen Bo tian li xin Jin Laboratory of Advanced Materials Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

A simple and general strategy is described for preparing network supported catalyst through a one-pot synthetic procedure using supramolecular gel as *** procedure directly attaches ligand to support during fabricating the *** this strategy,supported CuBr/di-（2-picolyl） amine catalyst with U-shaped fibrillar network was prepared and used in atom transfer radical polymerization of methyl *** and SEM characterization of the catalyst revealed homogeneous distribution of ligand,sufficient reactive sites,adequate mechanical strength and *** polymerization results demonstrated high activity and reusability of such *** strategy might be extended to other supported catalysts used in column reactors.

关键词： One-pot synthesis Network supported catalyst Supramolecular gel Atom transfer radical polymerization

Understanding deformation and fracture mechanism of Ti-55531 alloy under complex loading conditions:a case of pre-tensioned torsion

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Rare Metals 2024年第12期43卷 6673-6693页

作者： Kong-liang Hu Chao-Wen Huang Hong-Tao Zeng Jiang Yang Dan liu tian-xin li Ming-Pan Wan Yong-Qing Zhao National and Local Joint Engineering Laboratory for High Performance Metal Structure Materials and Advanced Manufacturing Technology Guizhou University Key Lab of Materials Structure and Strength of Guizhou Province Guizhou University College of Mechanical and Equipment Engineering Hebei University of Engineering School of Materials and Energy Engineering Guizhou Institute of Technology Northwest Institute for Nonferrous Metal Research

The deformation and fracture failure of aerospace structural components are primarily affected by complex loading *** study aims to investigate how various pre-tension strains（0%,4% and 6%） influence the torsional properties,deformation and fracture mechanism of the Ti-5Al-5Mo-5V-3Cr-1Zr（Ti-55531） alloy with the bimodal *** results indicate that increasing the pre-tension strain gradually decreases the torsional strength of ***,their torsional ductility initially increases（from 0 to 4% pre-tension strain） and then decreases（from 4 to 6% pre-tension strain）.This can be attributed to the significant influence of different pre-tension strains on the deformation mechanism of each phase in the *** pure torsion loading,the primary α（αp） phase mainly undergoes the {0002} basal slip for ***,at a pre-tension strain of4%,the torsional deformation mechanism of αptransforms into crossing reaction between the {1010} prismatic *** the pre-tension strain further increases to 6%,{1011}pyramidal slips were further ***,with an increase in pre-tension strain,there is a significant rise multiple slips probability within the ap during torsional *** contrary,for the secondary α（αs） phase,the probability of {1011}αtwins formation during torsional deformation firstly rises and then *** findings indicate that α phase,particularly ap,plays a crucial role in accommodating *** discovery offers valuable insights for further adjustments and optimizations of material microstructure and ***,modifying external load can alter the stress state of components and enhance their fracture resistance during service,thereby broadening their range of applications and improving material reliability.

关键词： Deformation behavior Fracture mechanism Metastable β titanium alloy Pre-tension strain Tension and torsion composite loads

Inhibition of allergic airway inflammation by antisense-induced blockade of STAT6 expression

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Chinese Medical Journal 2011年第1期124卷 26-31页

作者： tian xin-rui tian xin-li BO Jian-ping li Shao-gang liU Zhuo-la NIU Bo Department of Respiratory Diseases Second Hospital of Shanxi Medical University Taiyuan Shanxi 030001 China Capital Institute of Pediatrics Beijing 100020 China

Background The signal transducer and activator of transcription 6 （STAT6） expression in lung epithelial cells plays a pivotal role in asthma pathogenesis. Activation of STAT6 expression results in T helper cell type 2 （Th2） cell differentiation leading to Th2-mediated IgE production, development of allergic airway inflammation and hyperreactivity. Therefore, antagonizing the expression and/or the function of STAT6 could be used as a mode of therapy for allergic airway inflammation. Methods In this study, we synthesized a 20-mer phosphorothioate antisense oligonucleotide （ASODN） overlapping the translation starting site of STAT6 and constructed STAT6 antisense RNA （pANTI-STAT6）, then transfected them into murine spleen lymphocytes and analyzed the effects of antagonizing STAT6 function in vitro and in a murine model of asthma. Results In vitro, we showed suppression of STAT6 expression and interleukin （IL）-4 production of lymphocytes by STAT6 ASODN. This effect was more prominent when cells were cultured with pANTI-STAT6. In a murine model of asthma associated with allergic pulmonary inflammation in ovalbumin （OVA）-sensitized mice, local intranasal administration of fluorescein isothiocyanate （FITC）-Iabeled STAT6 ASODN to DNA uptake in lung cells was accompanied by a reduction of intracellular STAT6 expression. Such intrapulmonary blockade of STAT6 expression abrogated signs of lung inflammation, infiltration of eosinophils and Th2 cytokine production. Conclusion These data suggest a critical role of STAT6 in the pathogenesis of asthma and the use of local delivery of STAT6 ASODN as a novel approach for the treatment of allergic airway inflammation such as in asthma.

关键词： signal transducer and activator of transcription 6 antisense asthma lymphocyte Th2 cytokine

An end-to-end anastomosis model of guinea pig bile duct:A 6-mo observation

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World Journal of Gastroenterology 2011年第6期17卷 789-795页

作者： Xiao-Qing Zhang Yuan-Hu tian Zhi Xu li-xin Wang Chun-Sheng Hou Xiao-Feng ling Xiao-Si Zhou Department of General Surgery Peking University Third Hospital Beijing 100191 China

AIM:To establish the end-to-end anastomosis (EEA) model of guinea pig bile duct and evaluate the healing process of bile ***:Thirty-two male guinea pigs were randomly divided into control group,2-,3-,and 6-mo groups after establishment of EEA ***,immunohistochemical and serologic tests as well as measurement of bile contents were *** bile duct diameter and the diameter ratio (DR) were measured to assess the formation of relative ***:Acute and chronic inflammatory reactions occurred throughout the healing process of bile *** test and bile content measurement showed no formation of persistent stricture in 6-mo *** DR revealed a transient formation of relative stricture in 2-mo group in comparation to control group (2.94 ± 0.17 vs 1.89 ± 0.27,P=0.004).However,this relative stricture was released in 6-mo group (2.14 ± 0.18,P=0.440).CONCLUSION:A simple and reliable EEA model of guinea pig bile duct can be established with a good reproducibility and a satisfactory survival rate.

关键词： Animal model Guinea pig Anastomosis Common bile duct Wound healing

Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya li Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG xin tian Qi LU Institute of Ecological Conservation and Restoration Institute of Desertification Studies Chinese Academy of Forestry Institute of Desertification Institute of Desertification Studies Chinese Academy of Forestry Institute of Great Green Wall Satellite Application Centre for Ecology and Environment MEE Institute of Microelectronics Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences Institute of Forest Resource Information Techniques Chinese Academy of Forestry

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution （VHR） unmanned aerial vehicle （UAV） and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover （FWVC） and fractional herbaceous vegetation cover （FHVC） in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error （RMSE） values for the FWVC and FHVC models were 10.69% and 11.67%,and the R2values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10～6 *** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Tungsten-containing high-entropy alloys: a focused review of manufacturing routes, phase selection, mechanical properties, and irradiation resistance properties

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Tungsten 2021年第2期3卷 181-196页

作者： tian-xin li Jun-Wei Miao En-Yu Guo He Huang Jun Wang Yi-Ping Lu Tong-Min Wang Zhi-Qiang Cao Ting-Ju li Key Laboratory of Solidifi cation Control and Digital Preparation Technology(liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Institute of Materials China Academy of Engineering PhysicsMianyang 621907China State Key Laboratory of Solidifi cation Processing Northwestern Polytechnical UniversityXi’an 710072China High Entropy Alloy Materials Engineering Research Center(liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China

Alloying is one of the most effective means to confer superior properties to metal *** far too long,conventional W-based alloys were generally improved by the addition of minor *** exploitation of conventional W-based alloy is restricted to the corner of multielement phase diagrams with tiny compositional ***-entropy alloys(HEAs)are a novel kind of alloys consisting of multi-principal alloying elements(usually more than 4)and have attracted increasing attention,since they were first reported in *** emergence of HEAs filled the gap of the unexplored central region of multielement phase *** them,tungsten-containing HEAs(TCHEAs)exhibit excellent mechanical properties,especially at extraordinarily elevated ***,recent studies showed that TCHEAs had outstanding irradiation resistance *** might serve as a promising candidate for plasma-facing materials in the fusion *** characteristics of TCHEAs are different from other HEAs due to the addition of tungsten with ultrahigh-melting ***,this paper aimed to introduce the manufacturing routes of TCHEAs;review the phase selection,mechanical properties,and irradiation resistance properties of TCHEAs;and propose the future prospects of TCHEAs.

关键词： Tungsten-containing high-entropy alloys Irradiation resistance properties Mechanical properties Manufacturing routes Phase selection

1α,25-dihydroxyvitamin D 3 inhibits transforming growth factorβ1-induced epithelial-mesenchymal transition viaβ-catenin pathway

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Chinese Medical Journal 2020年第11期133卷 1298-1303页

作者： xin-Rong Xiong xin-li tian Ru-Jie Huo Yan-Ting Dong Dai liu Jing-Cui Bai Yun-Feng Qi xin-Rui tian Shanxi medical university TaiyuanShanxi 030001China Cardiopulmonary Center The Seventh Medical Center of People's Liberation Army General HospitalBeijing 100730China Department of Respiratory and Critical Care Medicine The Second Hospital of Shanxi Medical UniversityTaiyuanShanxi 030001China Department of Respiratory Medicine Jinhua Hospital of Traditional Chinese MedicineJinhuaZhejiang 321017China

Background::The transforming growth factorβ1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)has been proven associated with the pathogenesis of asthmatic airway remodeling,in which the Wnt/β-catenin pathway plays an important role,notably with regard to TGF-β*** studies have shown that 1α,25-dihydroxyvitamin D 3(1α,25(OH)2D 3)inhibits TGF-β1-induced EMT,although the underlying mechanism have not yet been fully ***::Alveolar epithelial cells were exposed to 1α,25(OH)2D 3,ICG-001,or a combination of both,followed by stimulation with TGF-β*** protein expression of E-cadherin,α-smooth muscle actin,fibronectin,andβ-catenin was analyzed by western blotting and immunofluorescence *** mRNA transcript of Snail was analyzed using RT-qPCR,and matrix metalloproteinase 9(MMP-9)activity was analyzed by gelatin *** activity of the Wnt/β-catenin signaling pathway was analyzed using the Top/Fop flash ***::Both 1α,25(OH)2D 3 and ICG-001 blocked TGF-β1-induced EMT in alveolar epithelial *** addition,the Top/Fop Flash reporters showed that 1α,25(OH)2D 3 suppressed the activity of the Wnt/β-catenin pathway and reduced the expression of target genes,including MMP-9 and Snail,in synergy with ***::1α,25(OH)2D 3 synergizes with ICG-001 and inhibits TGF-β1-induced EMT in alveolar epithelial cells by negatively regulating the Wnt/β-catenin signaling pathway.

关键词： 1α,25-Dihydroxyvitamin D3 Vitamin D β-Catenin Epithelial-mesenchymal transition Airway remodeling Asthma