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Journal of Magnesium and Alloys 2024年第6期12卷 2345-2359页

作者： Ke Liu Dalong Hu Feng Lou zijian Yu Shubo Li Xian du Wenbo du Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China

In this investigation,a high-strength Mg-12Gd-1.0Er-0.5Zr(wt.%)alloy sheet was produced by hot extrusion(HE)and subsequent hard-plate rolling(HPR)at different *** results indicate that the microstructures of these final-rolled sheets are inhomogeneous,mainly including coarse deformed grains and dynamic recrystallized(DRXed)grains,and the volume fraction of these coarse deformed grains increases as the rolling temperature ***,more DRXed grains can be found in R-385℃sheet,resulting in a smaller average grain size and weaker basal texture,while the biggest grains and the highest strong basal texture are present in R-450℃*** of dynamic precipitation ofβphases which are mainly determined by the rolling temperature are present in these sheets,and its precipitation can consume the content of Gd solutes in the *** a result,the lowest number density ofβphase in R-450℃sheet is beneficial to modify the age hardening ***,the R-450℃sheet displays the best age hardening response because of a severe traditional precipitation ofβ’(more)andβH/βM(less)precipitates,resulting in a sharp improvement in strength,*** tensile strength(UTS)of∼518±17 MPa and yield strength(YS)of∼438±18 ***,the elongation(EL)of this sheet reduces greatly,and its value is∼2.7±0.3%.By contrasting,the EL of the peak-aging R-385℃sheet keeps better,changing from∼4.9±1.2%to∼4.8±1.4%due to a novel dislocation-induced chain-like precipitate which is helpful to keep good balance between strength and ductility.

关键词： Mg-Gd-Er-Zr sheets Age hardening response Precipitates Mechanical properties

A sub-grid scale model for Burgers turbulence based on the artificial neural network method

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 162-165页

作者： Xin Zhao Kaiyi yin Department of Mechanics Beijing Institute of TechnologyBeijing 100081China

The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning *** filtered data of the direct numerical simulation is used to establish thetraining data set,the validation data set,and the test data *** artificial neural network(ANN)methodand Back Propagation method are employed to train parameters in the *** developed ANN is applied toconstruct the sub-grid scale model for the large eddy simulation of the Burgers turbulence in the *** proposed model well predicts the time correlation and the space correlation of the Burgers turbulence.

关键词： Artificial neural network Back propagation method Burgers turbulence Large eddy simulation Sub-grid scale model

The evolution analysis of agricultural global value chains

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Ecological Economy 2024年第2期20卷 178-187页

作者： DONG yin-guo ZHOU Xin-yi du Jian School of Business East China University of Science and TechnologyShanghai 200237CHINA

With the Uruguay Round bringing agricultural trade into multilateral regulation,the major countries have actively participated in agricultural global value chains(AGVC)and occupied an important position according to their comparative *** bilateral agricultural trade data of 66 countries based on the OECD Inter-Country-Input-Output Tables(OECD ICIO)from 2010 to 2018,this study applies social network analysis indicators to measure each country’s eigenvector centrality within AGVC and to examine the current global agricultural trade patterns,with particular attention to the changes in the status of world powers within *** main findings are as follows:first,with the multilateral and regional trade liberalization,growing numbers of developing nations,including China and India,are engaging in international agricultural trade,which contributes to its diversification;second,as AGVC develops,the structure of global agricultural trade networks has become more decentralized and *** is evidenced by the emergence of additional central nodes,and large nations like the United States,which formerly held the most central position as indicated by a drop in its centrality,are becoming less dominant.

关键词： agricultural global value chains centrality indicators world powers

Study on the tribological properties of metal rolling bearing under lubrication with diketone lubricants

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Science China(Technological Sciences) 2024年第7期67卷 2003-2017页

作者： du ShaoNan ZHANG ChenHui LUO Zhi State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Beijing National Laboratory of Molecular Sciences CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

In this article, 1-(4-ethylphenyl)-nonane-1,3-dione(0206) was prepared by Claisen condensation. By mixing 0206, chelate, and base oil in a ratio of 3.2:4.8:2, a diketone lubricant(PAO=14(20%)) that can achieve superlubricity was prepared and applied to bearing lubrication experiments. The experimental results show that when the bearing was lubricated by base oil, the friction coefficient(COF) and temperature rise decreased with the decrease of the viscosity of PAO. When PAO=14(20%) was used as the lubricant, the COF of the bearing was the lowest(0.001), and the wear morphology was comparable to that of the bearing lubricated with commercial lubricant. Compared with the base oil with the same viscosity, it is found that the COF and temperature rise of the bearing lubricated by PAO=14(20%) were lower under any experimental conditions. And when the amount of lubricant added was 10 μL, the COF of the bearing lubricated by PAO=14(20%) reached a very low value(0.0004).Bearing ball surface analysis identified the formation of diketone adsorption films. Combined with the previous PAO=14(20%)superlubricity mechanism, it was considered that the occurrence of tribochemical reaction and the bearing effect of chelates were the main reasons for the existence of ultra-low friction coefficient and low wear. In addition, when there were polar molecules in the lubricant, they were adsorbed on the metal surface through tribochemical reactions, resulting in many irregular pits on the surface.

关键词： superlubricity diketone chelate tribochemical recations bearing lubrication

Metal-organic framework-derived porous carbon for the advanced aqueous zinc-ion hybrid capacitor

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Journal of Central South University 2024年第7期31卷 2268-2279页

作者： LIU Wei-fang HU zi-han ZHANG Qi School of Chemistry and Chemical Engineering Hunan University of Science&TechnologyXiangtan 411201China Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China

Aqueous zinc ion hybrid capacitors(ziHCs)are considered one of the most promising electrochemical energy storage systems due to their high safety,environmental friendliness,low cost,and high power ***,the low energy density and the lack of sustainable design strategies for the cathodes hinder the practical application of ***,we design the N and O co-doped porous carbon cathode by annealing metal-organic framework(ziF-8).ziF-8 retains the original dodecahedral structure with a high specific surface(2814.67 m^(2)/g)and I_(G)/I_(D) ratio of 1.0 during carbonization and achieves self-doping of N and O *** defect sites are introduced into the porous carbon to provide additional active sites for ion adsorption after the activation of carbonized ziF-8 by KOH *** ziHCs assembled with modified ziF-8 as the cathode and commercial zinc foil as the anode show an energy density of 125 W∙h/kg and a power density of 79 W/*** addition,this ziHCs device achieves capacity retention of 77.8%after 9000 electrochemical cycles,which is attributed to the diverse pore structure and plentiful defect sites of ziF-8-800(KOH).The proposed strategy may be useful in developing high-performance metal-ion hybrid capacitors for large-scale energy storage.

关键词： zinc ion hybrid capacitor cathode metal-organic framework(ziF-8) KOH activation

Greedy Lattice Paths with General Weights

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2213-2222页

作者： yin Shan CHANG An Qi ZHENG College of Mathematics Sichuan UniversityChengdu 610065P.R.China

Let{X_(v):v∈Z^(d)}be *** *** S(π)=Σ_(v∈π)X_(v)be the weight of a self-avoiding lattice pathπ.Let M_(n)=max{S(π):πhas length n and starts from the origin}.We are interested in the asymptotics of Mn as n→∞.This model is closely related to the first passage percolation when the weights{X_(v):v∈Z^(d)}are non-positive and it is closely related to the last passage percolation when the weights{X_(v):v∈Z^(d)}are *** general weights,this model could be viewed as an interpolation between first passage models and last passage ***,this model is also closely related to a variant of the position of right-most particles of branching random *** the two assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)<+∞and that E[(X_(0)^(−))^(4)]<+∞,we prove that M_(n)/n converges to the same constant M almost surely as n tends to infinity.

关键词： Last passage percolation first passage percolation greedy lattice path

Revealing the role of calcium ion intercalation of hydrated vanadium oxides for aqueous zinc-ion batteries

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Journal of Energy Chemistry 2024年第8期95卷 9-19,I0001页

作者： Tao Zhou Xuan du Guo Gao Key Laboratory for Thin Film and Micro Fabrication of the Ministry of Education School of Sensing Science and EngineeringSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Exploring suitable high-capacity V_(2)O_(5)-based cathode materials is essential for the rapid advancement of aqueous zinc ion batteries(ziBs).However,the typical problem of slow Zn^(2+)diffusion kinetics has severely limited the feasibility of such *** this work,unique hydrated vanadates(CaVO,BaVO)were obtained by intercalation of Ca^(2+)or Ba^(2+)into hydrated vanadium *** the CaVO//Zn and BaVO//Zn batteries systems,the former delivered up to a 489.8 mAh g^(-1)discharge specific capacity at 0.1 A g^(-1).Moreover,the remarkable energy density of 370.07 Wh kg^(-1)and favorable cycling stability yard outperform BaVO,pure V_(2)O_(5),and many reported cathodes of similar ionic intercalation *** addition,pseudocapacitance analysis,galvanostatic intermittent titration(GITT)tests,and Trasatti analysis revealed the high capacitance contribution and Zn^(2+)diffusion coefficient of CaVO,while an in-depth investigation based on EIS elucidated the reasons for the better electrochemical performance of ***,ex-situ XRD,XPS,and TEM tests further demonstrated the Zn^(2+)insertion/extraction and Zn-storage mechanism that occurred during the cycle in the CaVO//Zn battery *** work provides new insights into the intercalation of similar divalent cations in vanadium oxides and offers new solutions for designing cathodes for high-capacity aqueous ziBs.

关键词： Aqueous zinc ion batteries Cathode materials Ion pre-intercalation Vanadium oxides Energy storage mechanism

Cavitation research with computational fluid dynamics:From Euler-Euler to Euler-Lagrange approach

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Journal of Hydrodynamics 2024年第1期36卷 1-23页

作者： Bin Ji zi-yang Wang Huai-yu Cheng Rickard E.Bensow State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Department of Mechanics and Maritime Sciences Chalmers University of TechnologyGothenburgSweden

Unsteady cavitating flow often contains vapor structures with a wide range of different length scales,from micro-bubbles to large cavities,which issues a big challenge to precisely investigate its evolution mechanism by computational fluid dynamics(CFD)*** present work reviews the development of simulation methods for cavitation,especially the emerging Euler-Lagrange ***,the progress of the numerical investigation of hot and vital issues is discussed,including cavitation inception,cloud cavitation inner structure and its formation mechanism,cavitation erosion,and cavitation *** is indicated that the Euler-Lagrange method can determine cavitation inception point *** cloud cavitation,the Euler-Lagrange method can reveal the source of microbubbles and their distribution law inside the shedding *** method also has advantages and great potential in assessing cloud cavitation-induced erosion and *** the ever-growing demands of cavitation simulation accuracy in basic research and engineering applications,how to improve the Euler-Lagrange method’s stability and applicability is still an open *** further promote the application of this advanced CFD simulation technology in cavitation research,some key issues are to be solved and feasible suggestions are put forward for further work.

关键词： numerical simulation Euler-Euler method Euler-Lagrange method bubble dynamicsgy,Gothenburg,Sweden

Early diagnosis and management of neonatal sepsis:a perspective

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World Journal of Pediatrics 2024年第4期20卷 303-306页

作者： Li‑Zhong du Neonatal Intensive Care Unit Children’s Hospital Zhejiang University School of MedicineNational Clinical Research Center for Child Health3333 Binsheng RoadHangzhou 310052China

Neonatal sepsis is an illness caused by bloodstream bacteria or fungal infections that affect newborn infants under 28 days of *** stands as a significant contributor to morbidity and mortality in neonatal intensive care units(NICUs).With the improved survival rates of very low-birth-weight or extremely premature infants,a growing number of these vulnerable infants are receiving intensive care and undergoing invasive procedures,making nosocomial infections a persistent challenge in *** mortality rate associated with neonatal sepsis varies depending on factors such as birth weight,gestational age,and other *** can also lead to a range of long-term health consequences,including neurodevelopmental disabilities like cerebral palsy,visual or hearing impairments,and cognitive ***,neonatal sepsis is linked to various adverse outcomes,including respiratory complications,bronchopulmonary dysplasia,nutritional and growth issues,and immunological dysfunction[1].due to its atypical clinical presentation and the low rate of specific diagnostic indicators,such as a positive blood culture,accurately diagnosing neonatal sepsis is ***,the appropriateness of antibiotic treatment is often a matter of controversy.

关键词： neonatal mortality diagnosis

Unveiling the secrets of gastrointestinal mucous adenocarcinoma survival after surgery with artificial intelligence:A population-based study

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2404-2418页

作者： Jie Song Xiang-Xiu Yan Fang-Liang Zhang Yong-Yi Lei zi-yin Ke Fang Li Kai Zhang Yu-Qi He Wei Li Chao Li Yuan-Ming Pan Department of Gastroenterology Dongying People’s HospitalDongying Hospital of Shandong Provincial Hospital GroupDongying 257000Shandong ProvinceChina Gastrointestinal Surgery Department Suining Central HospitalSuining 629000Sichuan ProvinceChina Obstetrical Department Suining Central HospitalSuining 629000Sichuan ProvinceChina School of Medicine Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107Guangdong ProvinceChina Department of Pathology Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049China General Department Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China Department of Gastroenterology Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China Department of Thoracic Surgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina Department of Gastroenterology Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049China Cancer Research Center Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China

BACKGROUND Research on gastrointestinal mucosal adenocarcinoma(GMA)is limited and controversial,and there is no reference tool for predicting postoperative *** To investigate the prognosis of GMA and develop predictive *** From the Surveillance,Epidemiology,and End Results database,we collected clinical information on patients with *** random sampling,the patients were divided into the discovery(70%of the total,for model training),validation(20%,for model evaluation),and completely blind test cohorts(10%,for further model evaluation).The main assessment metric was the area under the receiver operating characteristic curve(AUC).All collected clinical features were used for Cox proportional hazard regression analysis to determine factors influencing GMA’s *** This model had an AUC of 0.7433[95% confidence intervals(95%CI):0.7424-0.7442]in the discovery cohort,0.7244(GMA:0.7234-0.7254)in the validation cohort,and 0.7388(95%CI:0.7378-0.7398)in the test *** packaged it into Windows software for doctors’use and uploaded *** gastric adenocarcinoma had the worst prognosis,and these were protective factors of GMA:Regional nodes examined[hazard ratio(HR):0.98,95%CI:0.97-0.98,Pduring surgery can improve patient outcomes.

关键词： Deep learning Gastrointestinal mucous adenocarcinoma Overall survival Surgery Clinical tool