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Modified constitutive models for Inconel 718 considering current density and temperature in electrically assisted forming process

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Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： Xuan CUI rui ZHAO min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material forming.To develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 mm.The research focused on the two most widely recognized effects:the Joule thermal and the electric athermal effects.The mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects simultaneously.Two basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were proposed.It was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four models.Finally,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization model.The results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

Advances in bio-inspired electrocatalysts for clean energy future

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Nano Research 2024年第2期17卷 515-533页

作者： Jing-Wen Duan Mu min-rui Gao Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon neutrality.The unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research directions.Recently,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic systems.Various bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic reactions.Herein,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent years.First,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is introduced.Then,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively discussed.Subsequently,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the electrode.We conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

Diet and physical activity influence the composition of gut microbiota,benefit on Alzheimer's disease

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Food Science and Human Wellness 2024年第2期13卷 541-555页

作者： Jinyue Zhou min Tang Wanyi Li rui Fang Chunlan Tang Qinwen wang 无 School of Public Health Health Science CenterNingbo UniversityNingbo 315211China Department of Neurology Ningbo Rehabilitation HospitalNingbo 3151000China Ningbo Institute of Life and Health Industry University of Chinese Academy of SciencesNingbo 315100China Key Laboratory of Diagnosis and Treatment of Digestive System Tumors of Zhejiang Province Ningbo 315100China

Alzheimer's disease is a neurodegenerative disease with complex etiology.Gut microbiota influences the gutbrain axis,which may affect pathways related to the pathogenesis of Alzheimer's disease.Additionally,diet and physical activity are likely to affect the pathology of Alzheimer's disease as well as the gut microbiota.This demonstrates that it may be possible to prevent or halt the progression of Alzheimer's disease by regulating the gut microbiota using diet and physical activity strategies.Therefore,the present study reviews the association between these two interventions and gut microbiota in the human body.It also summarizes how these two interventions benefit Alzheimer's disease.Furthermore,the primary limitations of these two interventions are discussed and promising strategies are proposed,which may be beneficial to further study and develop the intervening measure for the progression of Alzheimer's disease.

关键词： Alzheimer’s disease Gut microbiota Brain-gut axis Diet Physical activity

Therapeutic utility of human umbilical cord-derived mesenchymal stem cells-based approaches in pulmonary diseases:Recent advancements and prospects

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World Journal of Stem Cells 2024年第2期16卷 70-88页

作者： min Meng Wei-Wei Zhang Shuang-Feng Chen Da-rui wang Chang-Hui Zhou Department of Central Laboratory Liaocheng People’s HospitalLiaocheng 252000Shandong ProvinceChina Department of Clinical Laboratory Liaocheng People’s HospitalLiaocheng 252000Shandong ProvinceChina

Pulmonary diseases across all ages threaten millions of people and have emerged as one of the major public health issues worldwide.For diverse disease con-ditions,the currently available approaches are focused on alleviating clinical symptoms and delaying disease progression but have not shown significant therapeutic effects in patients with lung diseases.Human umbilical cord-derived mesenchymal stem cells(UC-MSCs)isolated from the human UC have the capacity for self-renewal and multilineage differentiation.Moreover,in recent years,these cells have been demonstrated to have unique advantages in the treatment of lung diseases.We searched the Public Clinical Trial Database and found 55 clinical trials involving UC-MSC therapy for pulmonary diseases,including coronavirus disease 2019,acute respiratory distress syndrome,bron-chopulmonary dysplasia,chronic obstructive pulmonary disease,and pulmonary fibrosis.In this review,we summarize the characteristics of these registered clinical trials and relevant published results and explore in depth the challenges and opportunitiesfaced in clinical application.Moreover,the underlying mole-cular mechanisms involved in UC-MSC-based therapy for pulmonary diseases are also analyzed in depth.In brief,this comprehensive review and detailed analysis of these clinical trials can be expected to provide a scientific reference for future large-scale clinical application.

关键词： Pulmonary diseases Mesenchymal stem cells Human umbilical cord Cell therapy Clinical trials

Perioperative and long-term results of ultrasonography-guided single-and multiple-tract percutaneous nephrolithotomy for staghorn calculi

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World Journal of Clinical Cases 2024年第7期12卷 1243-1250页

作者： rui-Xiang Cheng Ni Dai Yan-min wang Pei Qi Fen Chen Department of Urology Wuhan Ninth HospitalWuhan 430081Hubei ProvinceChina Department of Urinary Pain Wuhan Hankou HospitalWuhan 430000Hubei ProvinceChina Pre-hospital Emergency Department Wuhan Puren HospitalWuhan 430081Hubei ProvinceChina Department of Orthopedic Trauma Surgery Wuhan Hankou HospitalWuhan 430000Hubei ProvinceChina Department of Ultrasound Hubei Provincial Hospital of Integrated Traditional Chinese and Western MedicineWuhan 430015Hubei ProvinceChina

BACKGROUND It is possible that this condition will lead to urosepsis and progressive deterioration of renal function in the absence of surgical intervention.Several recent clinical studies have shown that multi-tract percutaneous nephrolithotomy(MPCNL)has a similar stone free rate(SFR)as standard percutaneous nephrolithotomy(S-PCNL).As a result,M-PCNL was also recommended as a treatment option for staghorn calculi.AIM To examine the perioperative and long-term results of ultrasonography-guided single-and M-PCNL.METHODS This was a retrospective cohort study.Between March 2021 and January 2022,the urology department of our hospital selected patients for the treatment of staghorn calculi using percutaneous nephrolithotomy.The primary outcomes were com plication rate and SFR,and the characteristics of patients,operative parameters,laboratory measurements were also collected.RESULTS In total,345 patients were enrolled in the study(186 in the S-PCNL group and 159 in the M-PCNL group).The SFR in the M-PCNL group was significantly higher than that in the S-PCNL group(P=0.033).Moreover,the incidence rates of hydrothorax(P=0.03)and postoperative infection(P=0.012)were higher in the M-PCNL group than in the S-PCNL group.Logistic regression analysis demonstrated that post-operative white blood cell count(OR=2.57,95%CI:1.90-3.47,P<0.001)and stone size(OR=1.59,95%CI:1.27-2.00,P<0.001)were associated with a higher overall complication rate in the S-PCNL group.Body mass index(OR=1.22,95%CI:1.06-1.40,P=0.004)and stone size(OR=1.70,95%CI:1.35-2.15,P<0.001)were associated with increased overall complications in the M-PCNL group.CONCLUSION Multiple access tracts can facilitate higher SFR while slightly increasing the incidence of acceptable complications.

关键词： Single-tract percutaneous nephrolithotomy Multiple-tract percutaneous nephrolithotomy Staghorn calculi Ultrasonography

Microstructure evolution and mechanical properties of brazing joint for ultra-thin-walled Inconel 718 considering grain size effect and brazing temperature

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Chinese Journal of Aeronautics 2024年第2期37卷 541-556页

作者： rui ZHAO Yueshuai SONG Hui KANG min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high demands on its application.To achieve this objective,this study investigates the impact of three distinct brazing temperatures and five typical grain sizes on the brazed joints’mechanical properties and microstructure evolution process.Microstructural evolution analysis was conducted based on Electron Back Scatter Diffraction(EBSD),Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),High-Resolution Transmission Electron Microscopy(HRTEM),and Focused Ion Beam(FIB).Besides,the mechanical properties and fracture behavior were studied based on the uniaxial tension tests and in-situ tension tests.The findings reveal that the brazing joint’s strength is higher for the fine-grain capillary than the coarse-grain one,primarily due to the formation of a dense branch structure composed of G-phase in the brazing seam.The effects of grain size,such as pinning and splitting,are amplified at higher brazing temperatures.Additionally,micro-cracks initiate around brittle intermetallic compounds and propagate through the eutectic zone,leading to a cleavage fracture mode.The fracture stress of fine-grain specimens is higher than that of coarse-grain due to the complex micro-crack path.Therefore,this study contributes significantly to the literature by highlighting the crucial impact of grain size on the brazing properties of ultra-thin-walled Inconel 718 structures.

关键词： EYWORDS Ultra-thin-walled structure Brazing Inconel 718 Grain size effect Brazing temperature

Tracing monoclinic distortion in NCM532 cathode materials by in situ high-energy synchrotron X-ray diffraction

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Progress in Natural Science:Materials International 2024年第2期34卷 274-279页

作者： min Dong Qingya Sun Zhihua wang Zixin rui Zhe Zhang He Zhu Si Lan Herbert Gleiter Institute of Nanoscience School of Materials Science and Engineering Nanjing University of Science and Technology School of Mechanical Engineering Nanjing University of Science and Technology School of Materials Science and Engineering Henan University of Technology Center for Neutron Scattering City University of Hong Kong Shenzhen Research Institute

Layered LiNixCoyMnzO2（NCM） cathode materials have emerged as the best choice for high-energy-density lithium-ion batteries for powering electric vehicles.Despite significant research efforts,the understanding of complex structural dynamics during lithium（de-） intercalation still remains a subject of debate,especially in scenarios where morphology and composition vary.In this study,we carried out in situ high-energy synchrotron X-ray diffraction experiments on commercial NCM523cathode materials in both single crystal and polycrystalline forms to probe the structural changes during charging and discharging in detail.Our findings reveal that both single crystal and polycrystalline materials exhibit typical H1-H2-H3 phase transitions.However,in polycrystalline NCM532,a monoclinic intermediate phase emerges between the H1 and H2 phases.During this process,symmetry reduces from R-3m to C2/m,which is attributed to a shear distortion along the ab plane.In contrast,for single crystal materials,the H1 phase directly transforms into the H2 phase without the monoclinic phase.The observed monoclinic distortion significantly impacts structural stability and material cycling performance.This study provides new insight into the structural dynamics in NCM532 cathode materials,particularly concerning morphology-dependent behaviors,which could deepen our understanding of the relationship between NCM material structures and their performance.

关键词： CHEMISTRY

Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

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Petroleum Science 2024年第1期21卷 125-142页

作者： Mei Chen Sheng-He Wu rui-Feng wang Jia-Jia Zhang Peng-Fei Xie min wang Xiao-Feng wang Ji-Tao Yu Qi-Cong Xiong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Faculty of Geosciences University of BremenBremen28359Germany MARUM-Center for Marine and Environmental Sciences University of BremenBremen28359Germany Research institute of Petroleum Exploration and Development PetroChinaBeijing10083China School of Geosciences Yangtze UniversityWuhan 100083HubeiChina CNODC Mozambique Ltd. Beijing 100034China

Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East Africa.We characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic data.We find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single lobes.When the topography is irregular and presents topographic lows,lobe complexes first infill these depressions.Single lobes are deposited preferentially at positions with higher longitudinal(i.***.across-slope)slope gradients.As the longitudinal slope becomes higher,the aspect ratio of the single lobes increases.Lateral(i.***.along-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single lobes.When the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap surface.Furthermore,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,i.***.sediments tend to accumulate vertically.The results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

关键词： Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean

Different timing for abdominal paracentesis catheter placement and drainage in severe acute pancreatitis complicated by intraabdominal fluid accumulation

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 134-142页

作者： rui Chen Hua-Qiang Chen rui-Die Li Hui-min Lu Department of General Surgery Chengdu Sixth People’s HospitalChengdu 610058Sichuan ProvinceChina West China Center of Exellence for Pancreatitis Institute of Integrated Traditional Chinese and Western MedicineWest ChinaDivision of Pancreatic SurgeryDepartment of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina HospitalSichuan University

BACKGROUND Non-surgical methods such as percutaneous drainage are crucial for the treatment of patients with severe acute pancreatitis(SAP).However,there is still an ongoing debate regarding the optimal timing for abdominal paracentesis catheter place-ment and drainage.AIM To explore the influence of different timing for abdominal paracentesis catheter placement and drainage in SAP complicated by intra-abdominal fluid accumu-lation.METHODS Using a retrospective approach,184 cases of SAP complicated by intra-abdominal fluid accumulation were enrolled and categorized into three groups based on the timing of catheter placement:group A(catheter placement within 2 d of symptom onset,n=89),group B(catheter placement between days 3 and 5 after symptom onset,n=55),and group C(catheter placement between days 6 and 7 after symptom onset,n=40).The differences in progression rate,mortality rate,and the number of cases with organ dysfunction were compared among the three groups.RESULTS The progression rate of group A was significantly lower than those in groups B and groups C(2.25%vs 21.82%and 32.50%,P0.05).At postoperative day 3,the levels of C-reactive protein(55.41±19.32 mg/L vs 82.25±20.41 mg/L and 88.65±19.14 mg/L,P<0.05),procalcitonin(1.36±0.51 ng/mL vs 3.20±0.97 ng/mL and 3.41±0.98 ng/mL,P<0.05),tumor necrosis factor-alpha(15.12±6.63 pg/L vs 22.26±9.96 pg/L and 23.39±9.12 pg/L,P<0.05),interleukin-6(332.14±90.16 ng/L vs 412.20±88.50 ng/L and 420.08±87.65ng/L,P<0.05),interleukin-8(415.54±68.43 ng/L vs 505.80±66.90 ng/L and 510.43±68.23ng/L,P<0.05)and serum amyloid A(270.06±78.49 mg/L vs 344.41±81.96 mg/L and 350.60±80.42 mg/L,P<0.05)were significantly lower in group A compared to those in groups B and group C.The length of hospital stay in group A was significantly lower than

关键词： Abdominal paracentesis catheter drainage Timing Severe acute pancreatitis Intra-abdominal fluid Application value