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Multi-physics multi-scale simulation of unique equiaxed-to-columnar-to-equiaxed transition during the whole solidification process of Al-li alloy laser welding

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Journal of Materials Science & Technology 2024年第4期171卷 235-251页

作者： Chu Han Ping Jiang Shaoning geng liangyuan Ren School of Mechanical Science and Engineering Huazhong University of Science&Technology(HUST)Wuhan430074China

In this study,a novel multi-physics multi-scale model with the dilute multicomponent phase-field method in three-dimensional(3D)space was developed to investigate the complex microstructure evolu-tion in the molten pool during laser welding of Al-li *** accurately compute mass data within both two and three-dimensional computational domains,three efficient computing methods,including central processing unit parallel computing,adaptive mesh refinement,and moving-frame algorithm,were *** was placed on the distinctive equiaxed-to-columnar-to-equiaxed transition phenomenon that occurs during the entire solidification process of Al-li alloy laser *** results indi-cated that the growth distance of columnar grains that epitaxially grew from the base metal(BM)de-creased as the nucleation rate *** the nucleation rate increased,the morphology of the newly formed grains near the fusion boundary(FB)changed from columnar to equiaxed,and newly formed equiaxed grains changed from having high-order dendrites to no obvious dendrite *** the nucleation rate was sufficiently high,non-dendritic equiaxed grains could directly form near the FB,and there was nearly no epitaxial growth from the ***,simulation results illustrated the com-petition among multiple grains with varying orientations that grow in 3D space near the ***,how equiaxed grain bands develop was *** equiaxed band not only hindered the growth of early columnar grains but also some of its grains could grow epitaxially to form new columnar *** predicted results were in good agreement with experimental measurements and observations.

关键词： Laser welding Al-li alloy Equiaxed-to-columnar-to-equiaxed transition Multi-physics multi-scale model Multicomponent alloys 3D phase-field model

lithiophilic CoF2@C hollow spheres towards spatial lithium deposition for stable lithium metal batteries

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Journal of Energy Chemistry 2024年第10期97卷 55-67页

作者： Jianxing Wang Shuhao Yao Runming Tao xiaolang liu Jiazhi geng Chang Hong Huiying li Guiyun Yu Haifeng li xiao-Guang Sun Jianlin li Jiyuan liang School of Optoelectronic Materials & Technology Jianghan University Institute for Advanced Materials and Manufacturing University of Tennessee Applied Materials Division Argonne National Laboratory School of Chemistry & Chemical Engineering Yancheng Institute of Technology Chemical Sciences Division Oak Ridge National Laboratory

lithium metal（LM） is a promising anode for next-generation batteries due to its high theoretical capacity and low electrode ***,side reactions,volume change,and unwanted lithium dendrite growth seriously limit the practical application of ***,with the aid of a hard template approach,a novel lithiophilic CoF2-carbon hollow sphere（CoF2@C-HS） composite material is successfully prepared via a facile in-situ fluorination and etching *** lithiophilic CoF2acts as nucleation sites to reduce nucleation overpotential as well as induces the spatial li deposition and the formation of liFrich solid electrolyte interphase（SEI）,and the hollow carbon matrix can enhance the electrical conductivity and offer free space for LM *** simulations reveal that the synergistic effect of lithiophilic CoF2and hollow carbon matrix homogenizes the electric field distribution and li+*** from these advantages,the CoF2@C-HS-modified copper substrate electrode delivers an enhanced Coulombic efficiency（CE） of 93.7% for 280 cycles at 1 mA cm-2and 1 mA h *** symmetrical cell using CoF2@C-HS can stably cycle more than 1800 h with a low voltage hysteresis of 11 mV at a current density of 0.5 MA cm-2and an areal capacity of 0.5 mA h ***,the li@CoF2@C-HS composite anode enables more than 300 stable cycles at 1 C with a capacity retention of 95% in liFePO4-based full cell and 110 stable cycles at 1 C in liNi0.8Co0.1Mn0.1O2（NCM811）-based highvoltage full *** work might shed a new light on designing lithiophilic hosts to spatially confine LM deposition,realizing dendrite-free LM anodes and the practical applications of LM batteries.

关键词： lithiophilic CoF2 lithium metal anode Nanocomposite Spatial deposition, Stability

A Transient-Pressure-Based Numerical Approach for Interlayer Identification in Sand Reservoirs

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Fluid Dynamics & Materials Processing 2024年第3期20卷 641-659页

作者： Hao Luo Haibo Deng Honglin xiao Shaoyang geng Fu Hou Gang Luo Yaqi li Tight Oil and Gas Exploration and Development Project Department PetroChina Southwest Oil and Gas Field CompanyChengdu610051China Energy College Chengdu University of TechnologyChengdu610059China

Almost all sandstone reservoirs contain interlayers. The identification and characterization of these interlayers iscritical for minimizing the uncertainty associated with oilfield development and improving oil and gas *** interlayers outside wells using identification methods based on logging data and machine learning isdifficult and seismic-based identification techniques are expensive. Herein, a numerical model based on seepageand well-testing theories is introduced to identify interlayers using transient pressure data. The proposed modelrelies on the open-source MATLAB Reservoir Simulation Toolbox. The effects of the interlayer thickness, position,and width on the pressure response are thoroughly investigated. A procedure for inverting interlayer parametersin the reservoir using the bottom-hole pressure is also proposed. This method uses only transient pressuredata during well testing and can effectively identify the interlayer distribution near the wellbore at an extremelylow cost. The reliability of the model is verified using effective oilfield examples.

关键词： Sand reservoir interlayer identification transient pressure analysis numerical well test

High-efficiency PdNi single-atom alloy catalyst toward cross-coupling reaction

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Chinese Chemical Letters 2024年第7期35卷 480-483页

作者： Baokang geng Xiang Chu li liu lingling Zhang Shuaishuai Zhang xiao Wang Shuyan Song Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry Tsinghua UniversityBeijing 100084China

The preparation of Pd-based catalysts with rich electrons and a high atom dispersion rate is of great significance for improving the reactivity of cross-coupling reactions,which is a powerful tool for pharmaceutical and fine chemical ***,we report a PdNi single-atom alloy(SAA)catalyst in which isolated Pd single atoms are anchored onto the surface of Ni nanoparticles(NPs)applied for Suzuki coupling reactions and Heck coupling *** 0.1%PdNi SAA exhibits extraordinary catalytic activity(reaction rate:17,032.25 mmol h^(-1)gPd^(-1))toward the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid at 80℃for 1 *** excellent activity is supposed to attribute to the 100 percent utilization rate of Pd atoms and the highly stable surface zero-valance Pd atoms,which provides abundant sites and electrons for the adsorption and fracture of the C-X(X=Cl,Br,I)***,our work demonstrates the excellent application prospect of SAAs for cross-coupling reactions.

关键词： Single-atom alloy Cross-coupling reaction Palladium catalysis Heterogeneous catalysis High-efficiency

Microstructures and mechanical properties of in-situ TiB2/Al−xSi−0.3Mg composites

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Transactions of Nonferrous Metals Society of China 2021年第2期31卷 331-344页

作者： Yu-xuan liU Ri-chu WANG Chao-qun PENG Zhi-yong CAI Zhao-hui ZHOU xiao-geng li Xuan-yang CAO School of Materials Science and Engineering Central South UniversityChangsha 410083China National Key Laboratory of light High Strength Structural Materials Central South UniversityChangsha 410083China Changsha Advanced Materials Industrial Research Institute Changsha 410000China

In-situ 2 vol.%TiB2 particle reinforced Al−xSi−0.3Mg(x=7,9,12,15 wt.%)composites were prepared by the salt−metal reaction,and the microstructures and mechanical properties were *** results show that the TiB2 particles with a diameter of 20−80 nm and the eutectic Si with a length of 1−10μm are the main strengthening phases in the TiB2/Al−xSi−0.3Mg *** TiB2 particles promote grain refinement and modify the eutectic Si from needle-like to short-rod ***,the strengthening effect of TiB2 particles is weakened as the Si content exceeds the eutectic composition,which can be attributed to the formation of large and irregular primary *** axial tensile test results and fractography observations indicate that these composites show more brittle fracture characteristics than the corresponding alloy matrixes.

关键词： Al−Si alloy in-situ reaction aluminum matrix composite microstructure mechanical properties

Enhancing Relational Triple Extraction in Specific Domains:Semantic Enhancement and Synergy of Large Language Models and Small Pre-Trained Language Models

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Computers, Materials & Continua 2024年第5期79卷 2481-2503页

作者： Jiakai li Jianpeng Hu geng Zhang School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai201620China

In the process of constructing domain-specific knowledge graphs,the task of relational triple extraction plays a critical role in transforming unstructured text into structured *** relational triple extraction models facemultiple challenges when processing domain-specific data,including insufficient utilization of semantic interaction information between entities and relations,difficulties in handling challenging samples,and the scarcity of domain-specific *** address these issues,our study introduces three innovative components:Relation semantic enhancement,data augmentation,and a voting strategy,all designed to significantly improve the model’s performance in tackling domain-specific relational triple extraction *** first propose an innovative attention interaction *** method significantly enhances the semantic interaction capabilities between entities and relations by integrating semantic information fromrelation ***,we propose a voting strategy that effectively combines the strengths of large languagemodels(LLMs)and fine-tuned small pre-trained language models(SLMs)to reevaluate challenging samples,thereby improving the model’s adaptability in specific ***,we explore the use of LLMs for data augmentation,aiming to generate domain-specific datasets to alleviate the scarcity of domain *** conducted on three domain-specific datasets demonstrate that our model outperforms existing comparative models in several aspects,with F1 scores exceeding the State of the Art models by 2%,1.6%,and 0.6%,respectively,validating the effectiveness and generalizability of our approach.

关键词： Relational triple extraction semantic interaction large language models data augmentation specific domains

Nitrogen rhizodeposition from corn and soybean,and its contribution to the subsequent wheat crops

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Journal of Integrative Agriculture 2024年第7期23卷 2446-2457页

作者： Sainan geng Lantao li Yuhong Miao Yinjie Zhang xiaona Yu Duo Zhang Qirui Yang xiao Zhang Yilun Wang College of Resources and Environment Henan Agricultural UniversityZhengzhou 450002China

Nitrogen(N)is a key factor in the positive response of cereal crops that follow leguminous crops when compared to gramineous crops in rotations,with the nonrecyclable rhizosphere-derived N playing an important ***,quantitative assessments of differences in the N derived from rhizodeposition(NdfR)between legumes and gramineous crops are lacking,and comparative studies on their contributions to the subsequent cereals are *** this study,we conducted a meta-analysis of NdfR from leguminous and gramineous crops based on 34 observations published *** addition,pot experiments were conducted to study the differences in the NdfR amounts,distributions and subsequent effects of two major wheat(Triticum aestivum L.)-preceding crops,corn(Zea mays L.)and soybean(Glycine max L.),by the cotton wick-labelling method in the main wheat-producing areas of *** meta-analysis results showed that the NdfR of legumes was significantly greater by 138.93%compared to gramineous *** our pot experiment,the NdfR values from corn and soybean were 502.32 and 944.12 mg/pot,respectively,and soybean was also significantly higher than corn,accounting for 76.91 and 84.15%of the total belowground nitrogen of the plants,***,in different soil particle sizes,NdfR was mainly enriched in the large macro-aggregates(>2 mm),followed by the small macro-aggregates(2–0.25 mm).The amount and proportion of NdfR in the macro-aggregates(>0.25 mm)of soybean were 3.48 and 1.66 times higher than those of corn,respectively,indicating the high utilization potential of soybean *** the N accumulation of subsequent wheat,the contribution of soybean NdfR to wheat was approximately 3 times that of corn,accounting for 8.37 and 4.04%of the total N uptake of wheat,*** conclusion,soybean NdfR is superior to corn in terms of the quantity and distribution ratio of soil *** future field production,legume NdfR should be included in the nitrogen p

关键词： crop rotation nitrogen rhizodeposition meta-analysis soil aggregates nitrogen transfer

Congener-derived template to construct lithiophilic organic-inorganic layer/interphase for high volumetric capacity dendrite-free li metal batteries

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Chinese Chemical Letters 2024年第3期35卷 453-460页

作者： Kang Yang Long li Yuanbin xiao Qiaoli Zhang Chenpeng Xi Borong li Yan Yu Chengkai Yang Key Laboratory of Advanced Materials Technologies International(HongKong Macao and Taiwan)Joint Laboratory on Advanced Materials TechnologiesCollege of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

The development of lithium-metal batteries(LMBs)is seriously restricted by the out-of-control dendrites growth and infinite volume ***,a pervasive organic-inorganic layer construction strategy is reported for the composite lithium metal anode with congener-derived organic-inorganic solid electrolyte interphase(SEI).In this strategy,the organic-inorganic Ag@polydopamine(Ag@PDA)layer is coated on the arbitrary substrates by a simple two-step *** thin and stable congener-derived SEI is insitu formed with fewer inorganic components and more organic components during charging/*** polydopamine with sufficient adhesion groups and lithiophilic Ag layer realize near-zero nucleation overpotential during lithium *** low interface resistance and stable lithium deposition are ***,the practical areal and volumetric capacities of the composite anode with three-dimensional copper(3DCu)as the substrate are 10 mAh/cm^(2)and 1538 mAh/cm^3(*** mass of anode).The symmetrical cell shows very low polarization voltage(10 mV)and more than 2500 h cycles life at 1 mA/cm^(2)(1 mAh/cm^(2)).The liNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)-based full cells show improved capacity retention(82%)after 100 cycles at 0.5 *** modified lithiophilic anode with congener-derived interphase provides a promising strategy to realize the next-generation dendrite-free LMBs.

关键词： lithium metal anode Congener-derived lithiophilicity Volumetric capacity Organic-inorganic interphase

Early adenocarcinoma mixed with a neuroendocrine carcinoma component arising in the gastroesophageal junction: A case report

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 563-570页

作者： Yu-Qing Cheng geng-Fang Wang xiao-li Zhou Min lin Xin-Wen Zhang Qin Huang Department of Pathology The Affiliated Changzhou No.2 People’s Hospital of Nanjing Medical UniversityChangzhou 213164Jiangsu ProvinceChina Gastroenterology Center The Affiliated Changzhou No.2 People’s Hospital of Nanjing Medical UniversityChangzhou 213164Jiangsu ProvinceChina Graduate School Dalian Medical UniversityDalian 116044Liaoning ProvinceChina Department of Pathology Beth Israel Deaconess Medical Center and Harvard Medical SchoolBostonMA 02215United States

BACKGROUND Early adenocarcinoma mixed with a neuroendocrine carcinoma(NEC)component arising in the gastroesophageal junctional(GEJ)region is rare and even rarer in young ***,we report such a case in a 29-year-old Chinese *** SUMMARY This patient presented to our hospital with a 3-mo history of dysphagia and *** endoscopy revealed an elevated nodule in the distal esophagus 1.6 cm above the GEJ line,without Barrett’s esophagus or involvement of the gastric *** nodule was completely resected by endoscopic submu-cosal dissection(ESD).Pathological examination confirmed diagnosis of intra-mucosal adenocarcinoma mixed with an NEC component,measuring 1.5 ***,both adenocarcinoma and NEC components were positive for P53 with a Ki67 index of 90%;NEC was positive for synaptophysin and ***-generation sequencing of 196 genes demonstrated a novel germline mutation of the ERCC3 gene in the DNA repair pathway and a germline mutation of the RNF43 gene,a common gastric cancer driver gene,in addition to pathogenic somatic mutations in P53 and CHEK2 *** patient was alive without evidence of the disease 36 mo after *** Early adenocarcinoma with an NEC component arising in the distal esophageal side of the GEJ region showed evidence of gastric origin.

关键词： Adenocarcinoma Neuroendocrine carcinoma Gastroesophageal junction Next generation sequencing Case report