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Heterogeneous engineering of MnSe@NC@ReS_(2) core-shell nanowires for advanced sodium-/potassium-ion batteries

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Rare Metals 2024年第8期43卷 3713-3723页

作者： sheng-Jun Lu jin-Yi Lin Cai-Hong Wang Yu-Fei Zhang Yi Zhang Hao-Sen Fan College of Materials Science and Metallurgy Engineering Guizhou University Guiyang 550025China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211816China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) have been attracting great attentions and widely been exploited due to the abundant sodium/potassium ***,the preparation of high-powered anode materials for SIBs/PIBs plays a decisive role for the commercial applications of SIBs/PIBs in the *** selenides are a class of potential anode materials for SIBs/PIBs because of their small band gap and high electrical *** this work,MnSe and ReS_(2) core-shell nanowires connecting by polydopamine derived carbon nanotube(MnSe@NC@ReS_(2)) have been successfully synthesized from growing ReS_(2) nanosheets array on the surface of MnSe@NC nano wires,which present excellent Na^(+)/K^(+) storage *** applied as SIBs anode,the specific capacity of 300 mAh·g^(-1) was maintwined after 400 cycles at the current density of 1.0 A·g^(-1).Besides,it could also keep 120 mAh·g^(-1) specific capacity after 900 cycles at 1.0 A·g^(-1) for the anode of *** heterogeneous engineering and one-dimensional-two-dimensional(1D-2D) hybrid strategies could provide an ideal strategy for the synthesis of new hetero-structured anode materials with outstanding battery performance for SIBs and PIBs.

关键词： Heterogeneous engineering Core-shell nanowires MnSe@NC@ReS_(2)nanowires Na^(+)batteries K^(+)batteries

A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids

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Petroleum Science 2024年第3期21卷 1980-1991页

作者： Jian Li Yu-Xi Ji Xiao-Xiao Ni Kai-He Lv Xian-Bin Huang jin-sheng Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao26650ShandongChina Inspection and Testing Center of Huabei Oil Field Company PetroChinaRenqiu062552HebeiChina Drilling Fluid Research Institute CNPC Engineering Technology R&D Company LimitedBeijing102206China

During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a ***,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2-acrylamido-2-methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether *** to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and *** rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing *** DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling ***,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12 m L)after aging at high temperatures(up to200℃)and high salinity(saturated salt)***,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering.

关键词： Fluid loss reducer Temperature-and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking

CO_(2)flooding in shale oil reservoir with radial borehole fracturing for CO_(2)storage and enhanced oil recovery

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Petroleum Science 2024年第1期21卷 519-534页

作者： Jia-Cheng Dai Tian-Yu Wang jin-Tao Weng Kang-Jian Tian Li-Ying Zhu Gen-sheng Li State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China China National Oil and Gas Exploration and Development Company Limited Beijing100034China

This study introduces a novel method integrating CO_(2)flooding with radial borehole fracturing for enhanced oil recovery and CO_(2)underground storage,a solution to the limited vertical stimulation reservoir volume in horizontal well fracturing.A numerical model is established to investigate the production rate,reservoir pressure field,and CO_(2)saturation distribution corresponding to changing time of CO_(2)flooding with radial borehole fracturing.A sensitivity analysis on the influence of CO_(2)injection location,layer spacing,pressure difference,borehole number,and hydraulic fractures on oil production and CO_(2)storage is *** CO_(2)flooding process is divided into four *** in layer spacing will significantly improve oil production rate and gas storage ***,serious gas channeling can occur when the spacing is lower than 20 *** the pressure difference between the producer and injector,the borehole number,the hydraulic fracture height,and the fracture width can also increase the oil production rate and gas storage *** analysis shows that layer spacing and fracture height greatly influence gas storage and oil *** outcomes are expected to provide a theoretical basis for the efficient development of shale oil reservoirs in the vertical direction.

关键词： Shale oil Radial borehole fracturing Embedded discrete fracture model Enhanced oil recovery Carbon storage

Dynamic Analysis of A Deepwater Drilling Riser with A New Hang-off System

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China Ocean Engineering 2024年第1期38卷 29-41页

作者： LI Yan-wei LIU Xiu-quan WANG jin-long CHEN Guo-ming CHANG Yuan-jiang sheng Lei-xiang Centre for Offshore Engineering and Safety Technology China University of PetroleumQingdao 266580China National Engineering Laboratory of Offshore Geophysical and Exploration Equipment China University of PetroleumQingdao 266580China China CNOOC Research Institute Co. Ltd.Beijing 100028China

The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of *** approach leads to a challenging problem:coupling the dynamics of risers with a new hang-off system combined with multiple structures and complex *** accurately analyze the dynamic responses of the coupled system,a coupled dynamic model is established based on the Euler-Bernoulli beam-column theory and penalty function method.A comprehensive analysis method is proposed for coupled dynamic analysis by combining the finite element method and the Newmarkβ*** analysis program is also developed in MATLAB for dynamic *** simulation results show that the dynamic performances of the risers at the top part are significantly improved by the new hang-off system,especially the novel design,which includes the centralizer and articulation *** bending moment and lateral deformation of the risers at the top part decrease,while the hang-off joint experiences a great bending moment at the bottom of the lateral restraint area which requires particular attention in design and *** platform navigation speed range under the safety limits of risers expands with the new hang-off system in use.

关键词： deepwater drilling riser new hang-off system dynamic analysis finite element method penalty function method

Corrosion and in vitro cytocompatibility investigation on the designed Mg-Zn-Ag metallic glasses for biomedical application

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Journal of Magnesium and Alloys 2024年第4期12卷 1566-1580页

作者： Jian Wang Lingzhong Meng Weixin Xie Chen Ji Ronghua Wang Pinghu Zhang Liling jin Liyuan sheng Yufeng Zheng School of Mechanical Engineering Yangzhou UniversityYangzhou225127China Department of Materials Science and Engineering Seoul National UniversitySeoulSouth Korea Huizhou Port Customs Huizhou516081China Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases Institute of Translational MedicineMedical CollegeYangzhou UniversityYangzhou225009China Center for Research in Computational Thermochemistry(CRCT) Department of Chemical EngineeringEcole polytechnique de MontréalMontréalQuébecH3C 3A7Canada Shenzhen Institute Peking UniversityShenzhen 518057China PKU-HKUST ShenZhen-HongKong Institution Shenzhen518057China

In the present work,seven Mg-Zn-Ag alloys with the nominal composition of Mg_(96-x)Zn_(x)Ag_(4)(x=17,20,23,26,29,32,35 in at.%)were prepared by induction melting and single-roller *** X-ray diffraction(XRD)analyses indicate the metallic glasses with three composition of Mg_(73)Zn_(23)Ag_(4),Mg_(70)Zn_(26)Ag_(4),and Mg_(67)Zn_(29)Ag_(4)were obtained *** differential scanning calorimetry(DSC)measurement was used to obtain the characteristic temperature of Mg-Zn-Ag metallic glasses for the glass-forming ability *** maximum glass transition temperature(Trg)was found to be 0.525 with a composition close to Mg_(67)Zn_(29)Ag_(4),which results in the best glass-forming ***,the immersion test in simulated body fluid(SBF)demonstrate the relative homogeneous corrosion behavior of the Mg-Zn-Ag metallic *** corrosion rate of Mg-Zn-Ag metallic glasses in SBF solution decreases with the increase of Zn *** sample Mg_(67)Zn_(29)Ag_(4)has the lowest corrosion rate of 0.19mm/yr,which could meet the clinical application requirement *** in vitro cell experiments show that the Madin-Darby canine kidney(MDCK)cells cultured in sample Mg_(67)Zn_(29)Ag_(4)and its extraction medium have higher ***,the Mg-Zn-Ag metallic glasses exhibit obvious inhibitory effect on human rhabdomyosarcoma(RD)tumor *** present investigations on the glass-forming ability,corrosion behavior,cytocompatibility and tumor inhibition function of the Mg-Zn-Ag based metallic glass could reveal their biomedical application possibility.

关键词： Metallic glasses Mg-Zn-Ag Corrosion behavior In vitro cytocompatibility

Clinical significance of preoperative nutritional status in elderly gastric cancer patients undergoing radical gastrectomy:A singlecenter retrospective study

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2211-2220页

作者： Xi-Ning Zhao jing Lu Hong-Yong He sheng-jin Ge Department of Anesthesiology Zhongshan HospitalFudan UniversityShanghai 200032China Department of Nursing Zhongshan HospitalFudan UniversityShanghai 200032China Department of General Surgery/Emergency Surgery Zhongshan HospitalFudan UniversityShanghai 200032China

BACKGROUND The population of elderly patients with gastric cancer is increasing,which is a major public health issue in *** is one of the greatest risk factors for adverse clinical outcomes in elderly patients with gastric *** To investigate the preoperative nutritional status and its association with delayed discharge of elderly gastric cancer patients following radical *** A total of 783 patients aged 65 years and older harboring gastric adenocarcinoma and following radical gastrectomy were retrospectively analyzed from the prospectively collected database of Zhongshan Hospital of Fudan University between January 2018 and May *** The overall rate of malnutrition was 31.8%.The incidence of postoperative complications was significantly higher in the malnourished group compared to the well-nourished group(P<0.001).Nutritional characteristics in the malnourished group,including body mass index,prognostic nutritional index(PNI),albumin,prealbumin,and hemoglobin,were all significantly lower than those in the well-nourished *** percentage of patients who received postoperative total nutrient admixture was lower in the malnourished group compared to the wellnourished group(22.1%vs 33.5%,P=0.001).Age≥70 years(HR=1.216,95%CI:1.048-1.411),PNI<44.5(HR=1.792,95%CI:1.058-3.032),operation time≥160 minutes(HR=1.431,95%CI:1.237-1.656),and postoperative complications grade III or higher(HR=2.191,95%CI:1.604-2.991)were all recognized as independent risk factors associated with delayed *** Malnutrition is relatively common in elderly patients undergoing *** PNI is an independent risk factor associated with delay *** strategies are needed to improve the clinical outcome of these patients.

关键词： Gastric cancer Preoperative nutritional status Malnutrition Elderly Radical gastrectomy

Remaining useful life prediction for train bearing based on an ILSTM network with adaptive hyperparameter optimization

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Transportation Safety and Environment 2024年第2期6卷 75-86页

作者： Deqiang He jingren Yan Zhenzhen jin Xueyan Zou sheng Shan Zaiyu Xiang Jian Miao State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi Key Laboratory of Manufacturing System&Advanced Manufacturing Tec hnologySc hool of Mec hanical EngineeringGuangxi Univ ersityNanning 530004GuangxiChina Zhuzhou CRRC Times Electric Co. Ltd.Zhuzhou 412001HunanChina

Remaining useful life(RUL)prediction for bearing is a significant part of the maintenance of urban rail transit *** RUL is closely linked to the reliability and safety of train running,but the current prediction accuracy makes it difficult to meet the re-quirements of high reliability *** at the problem,a prediction model based on an improved long short-term memory(ILSTM)network is ***,the variational mode decomposition is used to process the signal,the intrinsic mode function with stronger representation ability is determined according to energy entropy and the degradation feature data is constructed com-bined with the time domain ***,to improve learning ability,a rectified linear unit(ReLU)is applied to activate a fully connected layer lying after the long short-term memory(LSTM)network,and the hidden state outputs of the layer are weighted by attention *** Harris Hawks optimization algorithm is introduced to adaptively set the hyperparameters to improve the performance of the ***,the ILSTM is applied to predict bearing *** experimental cases,the better perfor-mance in bearing RUL prediction and the effectiveness of each improving measures of the model are validated,and its superiority of hyperparameters setting is demonstrated.

关键词： train bearing remaining useful life prediction long short-term memory(LSTM) attention mechanism Harris Hawks op-timization(HHO)

Effect of Heat Treatment on Gradient Microstructure and Tensile Property of Laser Powder Bed Fusion Fabricated 15-5 Precipitation Hardening Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 181-195页

作者： sheng Cao Hongyu Liu jin Jiang Ke He Binghua Lv Hao Zhang Lujie Zhang jingrong Meng Hao Deng Xiaodong Niu Department of Mechanical Engineering College of EngineeringShantou UniversityShantou515063China China State Shipbuilding Co. Ltd.Huangpu Wenchong Shipbuilding Company Ltd.Guangzhou510715China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100080China Shantou Ruixiang Mould Co. Ltd.Shantou515041China Military Representative Office X of Unit 93147 Deyang618000China China National Erzhong Group Co. Deyang Wanhang Die Forging Co.Ltd.Deyang618013China

This work investigated the gradient microstructure evolution and tensile property of LPBF fabricated 15-5 precipitation hardening stainless steel in post-process direct ageing(DA)and solution treating&ageing(STA).The varied microstructures for austenite and small-sized oxide inclusions at different sample heights in the as-built(AB)condition was generally preserved after DA ***,austenite was almost disappeared,and oxide particle grew significantly after the STA *** a result,the tensile property differences in sample top and bottom for AB and DA conditions did not occur in the STA *** the influence of post-process heat treatment,the STA condition had the highest yield strength due to the highest volume fraction of nano-sized Cu ***,the DA specimen had the highest ultimate tensile strength and elongation owing to the considerable amount of austenite phase and associated transformation induced plasticity effect.

关键词： 15-5 PH stainless steel Laser powder bed fusion Heat treatment Gradient microstructures Tensile properties

Alpine grassland degradation intensifies the burrowing behavior of small mammals:evidence for a negative feedback loop

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Integrative Zoology 2024年第2期19卷 240-252页

作者： Zaiwei WANG Jiawen YAN Amy MARTIN Dianne HBRUNTON Jiapeng QU jin-sheng HE Weihong JI Zhibiao NAN State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhouChina Manaaki Whenua-Landcare Research LincolnNew Zealand School of Natural Sciences Massey University(Albany Campus)AucklandNew Zealand Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXiningChina Qinghai Haibei National Field Research Station of Alpine Grassland Ecosystem Northwest Institute of Plateau BiologyChinese Academy of SciencesXiningChina Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijingChina

Globally,grassland degradation is an acute ecological *** alpine grassland on the Tibetan Plateau,increased densities of various small mammals in degraded grassland are assumed to intensify the degradation process and these mammals are subject to lethal ***,whether the negative impact of small mammals is solely a result of population size or also a result of activity and behavior has not been *** this study,we use plateau pika as a model to compare population size,core area of colony,and the number of burrow entrances and latrines between lightly and severely degraded *** test whether the alleged contribution of pika to grassland degradation is a result of increased population size or increased burrowing activities of individuals in response to lower food *** found that grassland degradation resulted in lower plant species richness,plant height,and ***,the overall population size of pika was not significantly affected by location in lightly and severely degraded ***,pika core areas in severely grassland degradation were significantly larger and had significantly higher densities of burrows and *** study provides convincing evidence that habitat-induced changes in the behavior of small,burrowing mammals,such as pika,can exacerbate grassland *** finding has significant implications for managing small mammals and restoring degraded grassland ecosystems.

关键词： burrowing behavior grassland degradation plateau pika population size small mammals