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Elaborating strengthen mechanism of Pt-Ir solid solution superalloy at finite temperature

Rare Metals 2024年第3期43卷 1243-1256页

作者： Wei Yu Xiao-Yu Chong Yun-Xuan Zhou Meng-Di Gan ying-xue liang Yan Wei Ai-Min Zhang Chang-Yi Hu Xing-Yu Gao Li Chen Hai-Feng Song Jing Feng Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China Yunnan Precious Metals Laboratory Co.LTD Kunming650106China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing100088China

Pt-Ir alloy is potential superalloys used above 1300℃because of their high strength and creep ***,the ductility of Pt-Ir alloy has rapidly deteriorated with the increase of Ir,resulting in poor *** work quantitatively evaluated the solid solution strengthening(SSS)and grain refinement strengthening(GRS)of Pt-Ir alloy using first-principles calculations combined with experimental ***,the stretching force constants in the second nearest neighbor region(SFC^(2nd))of pure Ir(193.7 eV·nm^(-2))are 3.40 times that of pure Pt(57.0 eV·nm^(-2)),i.e.,the interatomic interaction is greatly enhanced with the increase of Ir content,which leads to the decrease of ductility,and modulus misfit plays a dominant role in ***,the physical mechanisms responsible for the hardness(H_(V))of Pt-Ir alloy,using the power-law-scaled function of electron work function coupled SSS and GRS,are attributed to the electron redistribution caused by different Ir ***,a thorough assessment of the thermodynamic characteristics of Pt-Ir binary alloy was conducted,culminating in development of a mapping model that effectively relates enmposition,temperature and *** results revealed that the compressive strength incrcases with the Ir content,and the highest strength was observed in Pt_(0.25)Ir_(0.75).This study provides valuable insights into the Pt-Ir alloy system.

关键词： Elastic properties Phonon Solid solution strengthen Force constants CALPHAD

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Intestinal bacterial overgrowth in the early stage of severe acute pancreatitis is associated with acute respiratory distress syndrome

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World Journal of Gastroenterology 2021年第15期27卷 1643-1654页

作者： xue-ying liang Tian-Xu Jia Mei Zhang Department of Gastroenterology Xuanwu HospitalCapital Medical UniversityBeijing 100053China

BACKGROUND In the early stage of acute pancreatitis(AP),a large number of cytokines induced by local pancreatic inflammation seriously damage the intestinal barrier function,and intestinal bacteria and endotoxins enter the blood,causing inflammatory storm,resulting in multiple organ failure,infectious complications,and other disorders,eventually leading to *** failure occurs early in the course of AP,accelerating its *** an alternative method to detect small intestinal bacterial overgrowth,the hydrogen breath test is safe,noninvasive,and convenient,reflecting the number of intestinal bacteria in AP *** study aimed to investigate the changes in intestinal bacteria measured using the hydrogen breath test in the early stage of AP to clarify the relationship between intestinal bacteria and acute lung injury(ALI)/acute respiratory distress syndrome(ARDS).Early clinical intervention and maintenance of intestinal barrier function would be highly beneficial in controlling the development of severe acute pancreatitis(SAP).AIM To analyze the relationship between intestinal bacteria change and ALI/ARDS in the early stage of *** A total of 149 patients with AP admitted to the intensive care unit of the Digestive Department,Xuanwu Hospital,Capital Medical University from 2016 to 2019 were finally enrolled,following compliance with the inclusion and exclusion *** results of the hydrogen breath test within 1 wk of admission were collected,and the hydrogen production rates at admission,72 h,and 96 h were *** higher the hydrogen production rates the more bacteria in the small ***,according to the improved Marshall scoring system in the 2012 Atlanta Consensus on New Standards for Classification of Acute Pancreatitis,66 patients with a PaO2/FiO2 score≤1 were included in the mild AP(MAP)group,18 patients with a PaO2/FiO2 score≥2 and duration<48 h were included in the moderately SAP(MSAP)group,and 65 patients wi

关键词： Acute respiratory distress syndrome Hydrogen breath test Intestinal bacterial overgrowth Severe acute pancreatitis Interleukin-6 Acute lung injury

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Epidemiological investigation of Helicobacter pylori infection in elderly people in Beijing

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World Journal of Clinical Cases 2020年第11期8卷 2173-2180页

作者： Hong-Ming Zhu Bang-Yi Li Zhe Tang Jing She xue-ying liang Li-Kou Dong Mei Zhang Department of Gastroenterology Xuanwu HospitalCapital Medical UniversityBeijing 100053China National Geriatric Disease Clinical Medical Research Center Xuanwu HospitalBeijing 100053China

BACKGROUND The Helicobacter pylori(***)infection rate in China is approximately 50%.*** is a pathogenic factor of peptic ulcer and chronic *** addition,*** infection may also be associated with a variety of cardiovascular diseases in elderly people,such as arteriosclerosis,coronary heart disease,and cerebral infarction,having deleterious effect on their *** the aging of the population,the disease characteristics of the elderly population have been increasingly valued by the whole *** conducted an epidemiological survey of *** infection among elderly people in Beijing to provide a basis for health management of *** *** To understand the epidemiological characteristics of *** infection in elderly people in *** A total of 1090 elderly people aged more than 60 years from different parts of Beijing(urban and rural areas)were selected using the random cluster sampling *** questionnaires were completed during home visits and the 13C-urea breath test was conducted for *** *** The prevalence of *** infection was 46.5%(507/1090).The infection rate in men was 51.8%,which was significantly higher than that in women(42.5%;P<0.05).The *** infection rate in illiterate people was significantly higher than that in literate persons(53.5%vs 44.8%,P<0.05).The total infection rate of *** gradually increased with age and the difference was statistically significant(P<0.01).The *** infection rate in smokers was significantly higher than that in non-smokers and those who had quit smoking(P<0.05).CONCLUSION The prevalence of *** infection among elderly people is 46.5%and the infection rate gradually increases with ***,education level,age,and smoking were determined to be *** infection risk *** relationship of *** infection with region,occupation,drinking,and diet structure needs to be further studied.

关键词： Helicobacter pylori Epidemiologic Elderly persons 13C-urea breath test Prevalence Characteristics

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The Boundary Element Method for Ordinary State-Based Peridynamics

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2807-2834页

作者： xue liang Linjuan Wang State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceCollege of EngineeringPeking UniversityBeijing100871China CAPT-HEDPS and IFSA Collaborative Innovation Center of MoECollege of EngineeringPeking UniversityBeijing100871China School of Astronautics Beihang UniversityBeijing100191China

The peridynamics(PD),as a promising nonlocal continuum mechanics theory,shines in solving discontinuous *** to now,various numerical methods,such as the peridynamic mesh-free particlemethod(PD-MPM),peridynamic finite element method(PD-FEM),and peridynamic boundary element method(PD-BEM),have been ***-BEM,in particular,outperforms other methods by eliminating spurious boundary softening,efficiently handling infinite problems,and ensuring high computational ***,the existing PD-BEM is constructed exclusively for bond-based peridynamics(BBPD)with fixed Poisson’s ratio,limiting its applicability to crack propagation problems and scenarios involving infinite or semi-infinite *** this paper,we address these limitations by introducing the boundary element method(BEM)for ordinary state-based peridynamics(OSPD-BEM).Additionally,we present a crack propagationmodel embeddedwithin the framework ofOSPD-BEM to simulate crack *** validate the effectiveness of OSPD-BEM,we conduct four numerical examples:deformation under uniaxial loading,crack initiation in a double-notched specimen,wedge-splitting test,and threepoint bending *** results demonstrate the accuracy and efficiency of OSPD-BEM,highlighting its capability to successfully eliminate spurious boundary softening phenomena under varying Poisson’s ***,OSPDBEMsignificantly reduces computational time and exhibits greater consistencywith experimental results compared to PD-MPM.

关键词： Ordinary state-based peridynamics boundary element method crack propagation fracture toughness

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Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-liang Xu ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

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All types of base conversions allowed by base editors

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Science China(Life Sciences) 2024年第2期67卷 431-433页

作者： Shun-Qing liang Wen xue RNA Therapeutics Institute UMass Chan Medical SchoolWorcester 01655USA Department of Molecular Cell and Cancer BiologyUMass Chan Medical SchoolWorcester 01655USA Department of Molecular Medicine UMass Chan Medical SchoolWorcester 01655USA Li Weibo Institute for Rare Diseases Research UMass Chan Medical SchoolWorcester 01655USA

Base editors(BEs) hold great promise as tools for introducing single-base-pair changes in both basic research and therapeutic applications(Rees and Liu,2018).Base editors are composed of a Cas9 nickase fused to a DNA-modifying enzyme,which chemically modifies nucleobases within a specific targeting window near the Cas9-binding site.

关键词： base bases allowed

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Flame-assisted ultrafast synthesis of functionalized carbon nanosheets for high-performance sodium storage

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Carbon Energy 2024年第7期6卷 123-133页

作者： Chen Chen Dong Yan Yew Von Lim Lei Liu xue liang Li Junjie Chen Tian Chen Li Youyu Zhu Jiangtao Cai ying Huang Yating Zhang Hui ying Yang School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi'anChina Pillar of Engineering Product Development Singapore University of Technology and DesignSingaporeSingapore School of Electrical Engineering Xi'an University of TechnologyXi'anChina International Joint Laboratory of New Energy Materials and Devices of Henan Province School of Physics and ElectronicsHenan UniversityKaifengChina College of Chemistry and Chemical Engineering Xi'an University of Science and TechnologyXi'anChina

The unique structural features of hard carbon(HC)make it a promising anode candidate for sodium-ion batteries(SIB).However,traditional methods of preparing HC require special equipment,long reaction times,and large energy consumption,resulting in low throughputs and *** our contribution,a novel synthesis method is proposed,involving the formation of HC nanosheets(NS-CNs)within minutes by creating an anoxic environment through flame combustion and further introducing sulfur and nitrogen sources to achieve heteroatom *** effect of heterogeneous element doping on the microstructure of HC is quantitatively analyzed by high-resolution transmission electron microscopy and image processing *** with density functional theory calculation,it is verified that the functionalized HC exhibits stronger Na^(+)adsorption ability,electron gain ability,and Na^(+)migration *** a result,NS-CNs as SIB anodes provide an ultrahigh reversible capacity of 542.7mAh g^(-1) at 0.1Ag^(-1),and excellent rate performance with a reversible capacity of 236.4mAh g^(-1) at 2Ag^(-1) after 1200 ***,full cell assembled with NS-CNs as the can present 230mAh g^(-1) at 0.5Ag^(-1) after 150 ***,in/ex situ techniques confirm that the excellent sodium storage properties of NS-CNs are due to the construction of abundant active sites based on the novel synthesis method for realizing the reversible adsorption of Na^(+).This work provides a novel strategy to develop novel carbons and gives deep insights for the further investigation of facile preparation methods to develop high-performance carbon anodes for alkali-ion batteries.

关键词： carbon nanosheets heteroatom doping sodium-ion battery sustainable materials

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Peroxisome proliferator-activated receptor gamma coactivator-1(PGC-1)family in physiological and pathophysiological process and diseases

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1249-1292页

作者： Lu Qian Yanli Zhu Chao Deng Zhenxing liang Junmin Chen ying Chen xue Wang Yanqing Liu Ye Tian Yang Yang Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases Xi'an No.3 HospitalThe Affiliated Hospital of Northwest UniversityNorthwest UniversityXi'an 710021China Xi'an Key Laboratory of Innovative Drug Research for Heart Failure Faculty of Life Sciences and MedicineNorthwest University229 Taibai North RoadXi'an 710069China Department of Cardiovascular Surgery The First Affiliated Hospital of Xi'an Jiaotong University277 Yanta West RoadXi'an 710061China Department of Cardiothoracic Surgery The First Affiliated Hospital of Zhengzhou University1 Jianshe EastZhengzhou 450052China Department of Hematology The First Affiliated Hospital of Xi'an JiaotongUniversity277 Yanta West RoadXi'an 710061China

Peroxisome proliferator-activated receptor gamma coactivator-1(PGC-1)family(PGC-1s),consisting of three members encompassing PGC-1a,PGC-1β,and PGC-1-related coactivator(PRC),was discovered more than a quarter-century ***-1s are essential coordinators of many vital cellular events,including mitochondrial functions,oxidative stress,endoplasmic reticulum homeostasis,and *** evidence has shown that PGC-1s are implicated in many diseases,such as cancers,cardiac diseases and cardiovascular diseases,neurological disorders,kidney diseases,motor system diseases,and metabolic *** the upstream modulators and co-activated partners of PGC-1s and identifying critical biological events modulated by downstream effectors of PGC-1s contribute to the presentation of the elaborate network of ***,discussing the correlation between PGC-1s and diseases as well as summarizing the therapy targeting PGC-1s helps make individualized and precise intervention *** this review,we summarize basic knowledge regarding the PGC-1s family as well as the molecular regulatory network,discuss the physio-pathological roles of PGc-1s in human diseases,review the application of PGC-1s,including the diagnostic and prognostic value of PGC-1s and several therapies in pre-clinical studies,and suggest several directions for future *** review presents the immense potential of targeting PGC-1s in the treatment of diseases and hopefully facilitates the promotion of PGC-1s as new therapeutic targets.

关键词： diseases life precise

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Rainbow Pancyclicity in a Collection of Graphs Under the Dirac-type Condition

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 269-274页

作者： Lu-yi LI Ping LI xue-liang LI Center for Combinatorics and LPMC Nankai UniversityTianjin 300071China School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710062China

Let G={Gi:i∈[n]} be a collection of not necessarily distinct n-vertex graphs with the same vertex set V,where G can be seen as an edge-colored(multi)graph and each Gi is the set of edges with color i.A graph F on V is called rainbow if any two edges of F come from different Gis’.We say that G is rainbow pancyclic if there is a rainbow cycle Cℓof lengthℓin G for each integerℓ2[3,n].In 2020,Joos and Kim proved a rainbow version of Dirac’s theorem:Ifδ(Gi)≥2/n for each i∈[n],then there is a rainbow Hamiltonian cycle in *** this paper,under the same condition,we show that G is rainbow pancyclic except that n is even and G consists of n copies of Kn/2,n/*** result supports the famous meta-conjecture posed by Bondy.

关键词： rainbow Hamiltonian cycle rainbow pancyclic meta-conjecture

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An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi Liu xue-Dong Li liang Cheng Li Liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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