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Particuology 2024年第8期91卷 88-105页

作者： han wang.wantao ding Weimin Yang Chengzhen wang Wenduan Yu Zhicheng wang School of Qilu Transportation Shandong UniversityJinan250002China China Railway 14th Bureau Group Co. LtdJinan250101China

The rapid discharge of cuttings from the air cushion chamber is crucial for the construction safety and excavation efficiency of the slurry *** studies have mainly focused on the transport characteristics of cuttings in the slurry discharge pipe,while the complete process of cuttings entering the slurry discharge pipe from the air cushion chamber until they are discharged was often *** on the CFD-DEM coupling method and combined with actual engineering,this paper established a numerical model that can more completely reflect the cuttings discharge process during slurry shield tunneling,and the effects of the slurry velocity at slurry gate and scouring pipes,inclination angle of slurry discharge pipe,cuttings diameter and shape coefficient were investigated by analyzing the variation in the mass flow rate,mass of discharged cuttings,and discharged *** results revealed that increasing the slurry velocity can promote the discharge of *** keep the discharged rate at a high level,it is recommended that the slurry velocity at the slurry gate should be greater than 0.15 m/*** the inclination angle of the discharge pipe is conducive to the rapid discharge of *** with large diameter or small shape coefficient are more prone to accumulate in the air cushion chamber and cause clogging *** research results not only help to improve engineers'understanding of cuttings discharge in slurry shield,but also provide practical guidance for formulating relevant construction measures.

关键词： Slurry shield CFD-DEM coupling method Cuttings discharge Aircushion chamber Slurry discharge pipe

Data-driven discovery of linear dynamical systems from noisy data

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Science China(Technological Sciences) 2024年第1期67卷 121-129页

作者： wang YaSen YUAN Ye FANG HuaZhen ding han School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering University of KansasLawrence 66045USA

In modern science and engineering disciplines,data-driven discovery methods play a fundamental role in system modeling,as data serve as the external representations of the intrinsic mechanisms within ***,empirical data contaminated by process and measurement noise remain a significant obstacle for this type of *** this study,we have developed a data-driven method capable of directly uncovering linear dynamical systems from noisy *** method combines the Kalman smoothing and sparse Bayesian learning to decouple process and measurement noise under the expectation-maximization framework,presenting an analytical method for alternate state estimation and system ***,the discovered model explicitly characterizes the probability distribution of process and measurement noise,as they are essential for filtering,smoothing,and stochastic *** have successfully applied the proposed algorithm to several simulation *** results demonstrate its potential to enable linear dynamical system discovery in practical applications where noise-free data are intractable to capture.

关键词： system identification sparse Bayesian learning Kalman smoothing process and measurement noise

Mo Doping and Electrochemical Activation Co-Induced Vanadium Composite as High-Rate and Long-Life Anode for Ca-Ion Batteries

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Energy & Environmental Materials 2024年第5期7卷 135-143页

作者： Hongchen Pan Chunfang wang Minling Qiu Yaxin wang Cuiping han ding Nan College of Chemistry and Chemical Engineering Inner Mongolia University Songshan Lake Materials Laboratory The State Key Laboratory of Powder Metallurgy Central South University Faculty of Materials Science and Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced Technology Chinese Academy of Sciences

Calcium-ion batteries have been considered attractive candidates for largescale energy storage applications due to their natural abundance and low redox potential of Ca2+/Ca. However, current calcium ion technology is still hampered by the lack of high-capacity and long-life electrode materials to accommodate the large Ca2+（1.00?）. Herein, an amorphous vanadium structure induced by Mo doping and in-situ electrochemical activation is reported as a high-rate anode material for calcium ion batteries. The doping of Mo could destroy the lattice stability of VS4material, enhancing the flexibility of the structure. The following electrochemical activation further converted the material into sulfide and oxides co-dominated composite （defined as MoVSO）, which serves as an active material for the storage of Ca2+during cycling. Consequently, this amorphous vanadium structure exhibits excellent rate capability, achieving discharge capacities of 306.7 and 149.2 mAh g-1at5 and 50 A g-1and an ultra-long cycle life of 2000 cycles with 91.2%capacity retention. These values represent the highest level to date reported for calcium ion batteries. The mechanism studies show that the material undergoes a partial phase transition process to derive MoVSO. This work unveiled the calcium storage mechanism of vanadium sulfide in aqueous electrolytes and accelerated the development of high-performance aqueous calcium ion batteries.

关键词： calcium-ion batteries electrochemical activation phase transformation vanadium sulfide

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： ding Xin-dong wang Shu-qing LIU Wen-cheng YE Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

Atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction

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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： ding-han Zhu Xiong Zhang Xiao-Qiang Li Peng Li Yan-Bin wang Shuang Zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

Effect of the Retarder on Initial Hydration and Mechanical Properties of the"one-step"Alkaliactivated Composite Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1199-1213页

作者： ding Rui HE Yue LI Xingchen LI han TIAN Hao wang Hongen School of Materials Science and Engineering Jilin Jianzhu UniversityChangchun 130118China Ziyang Urban Construction Investment Group Co. LtdNanchong 637000China Shandong Taihe Urban Construction Development Co. Ltd.Jining 272000China

This paper studied the effects of different retarders on the performance of the"one-step"alkali-activated composite cementitious material(ACCM)which is composed of ground granulated blast slag(GGBS)and fly ash(FA),and analyzed its mechanical properties,hydration mechanism,and retardation *** effects of retarders on the hydration products,mechanical properties,and hydration kinetics of ACCM were investigated using XRD,SEM,FTIR,EDS,and thermoactive *** results showed that Na_(2)B_(4)O_(7)·10H_(2)O(B)delayed the exotherm during the alkali activation process and could effectively delay the setting time of ACCM,but the mechanical properties were slightly *** setting time of ACCM increased with the increase in SG content,but the mechanical properties of ACCM decreased with the increase in SG content.C1_(2)H_(22)O_(11)(CHO)could effectively delay the hydration reaction of ACCM and weakly enhanced the compressive strength.H_(3)PO_(4)(HP)at a concentration of 0.05 mol/L had a certain effect on ACCM retardation,but HP at a concentration of 0.07 and 0.09 mol/L had an effect of promoting the setting and hardening time of ACCM.

关键词： "one-step"alkali-activated composite cementitious materials solid activator hydration mechanism retarder retarding mechanism

Reconstructed parallel sites enhance the reactive oxygen tolerance of non-noble metal catalyst for durable proton exchange membrane fuel cells

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Science China Chemistry 2024年第11期67卷 3739-3748页

作者： Wenjie wang Hui ding Minghao wang han Cheng Xiang Shi Lin wang Chun wang wangsheng Chu Yi Xie Changzheng Wu National Synchrotron Radiation Laboratory University of Science and Technology of China School of Chemistry and Materials Science CAS Center for Excellence in Nanoscience University of Science & Technology of China Zhejiang Institute of Photoelectronics Institute of Energy Hefei Comprehensive National Science Center

The establishment of reactive oxygen species(ROS) elimination sites in iron-nitrogen-carbon(Fe-N-C) electrocatalysts to achieve durable proton-exchange membrane fuel cells(PEMFCs) performance has attracted broad interest. However, realizing ROS removal efficiency and oxygen reduction reaction(ORR) activity within a single system represents a significant challenge to date. Herein, we demonstrate uniform ROS elimination sites and ORR centers through an electrochemical reconstruction method on the parallel sites of Fe@Ce NC electrocatalyst for durable PEMFC. During the reconstruction process, the Fe sites can retain their original configuration. Meanwhile, the pristine Ce clusters will evolve into more efficient, highly dispersed ***, the reconstructed Fe and Ce sites exhibit favorable energy barriers for the ORR and ROS elimination pathways,respectively, thereby maintaining ORR activity and achieving high ROS tolerance. Consequently, the PEMFC assembled with our catalyst shows only a 2% decay in power density after the accelerated durability test. We anticipate that this parallel structure design will provide new insight into the development of more durable electrocatalysts for PEMFCs.

关键词： parallel reaction pathways sites reconstruction oxygen reduction reaction radical elimination fuel cells

Downregulation of Serum PTEN Expression in Mercury-Exposed Population and PI3K/AKT Pathway-Induced Inflammation

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Biomedical and Environmental Sciences 2024年第4期37卷 354-366页

作者： MEI Peng ding En Min YIN Hao Yang ding Xue Xue wang Huan wang Jian Feng han Lei ZhanG Heng Dong ZHU Bao Li School of Public Health Nanjing Medical UniversityNanjing 210000JiangsuChina Institute of Occupational Disease Prevention Jiangsu Province Center for Disease Prevention and ControlNanjing 21000JiangsuChina Suzhou Center for Disease Prevention and Control Suzhou 215004JiangsuChina Center for Global Health School of Public HealthNanjing Medical UniversityNanjing 210000JiangsuChina

Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological *** Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTEN lowexpression models were established in vitro using 293T cells. PTEN gene expression was assessed using qRT-PCR, and Western blotting was used to measure PTEN, AKT, and PI3K protein levels. IL-6 expression was determined by *** Combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTEN expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 ***, a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K, AKT, and IL-6 *** This is the first study to report that Hg exposure downregulates the PTEN gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation.

关键词： PTEN Occupational mercury exposure Occupational health PI3K/AKT pathway 293T cell IL-6

Human umbilical cord mesenchymal stem cell-derived exosomes loaded into a composite conduit promote functional recovery after peripheral nerve injury in rats

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Neural Regeneration Research 2024年第4期19卷 900-907页

作者： Haoshuai Tang Junjin Li Hongda wang Jie Ren han ding Jun Shang Min wang Zhijian Wei Shiqing Feng Department of Othopaedics Tianjin Medical University General Hospital International Science and Technology Cooperation Base of Spinal Cord Injury Tianjin Key Laboratory of Spine and Spinal Cord InjuryDepartment of OrthopedicsTianjin Medical University General Hospital Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment Tianjin Lung Cancer InstituteTianjin Medical University General Hospital Department of Othopaedics Qilu Hospital of Shandong UniversityShandong University Centre for OthopedicsAdvanced Medical Research InstituteShandong University Orthopedic Research Center of Shandong University&Advanced Medical Research Institute Cheeloo College of MedicineShandong University

Complete transverse injury of peripheral nerves is challenging to *** secreted by human umbilical cord mesenchymal stem cells are considered to play an important role in intercellular communication and regulate tissue *** previous studies,a collagen/hyaluronic acid sponge was shown to provide a suitable regeneration environment for Schwann cell proliferation and to promote axonal *** three-dimensional(3D)composite conduit contains a collagen/hyaluronic acid inner sponge enclosed in an electrospun hollow poly(lactic-co-glycolic acid)***,whether there is a synergy between the 3D composite conduit and exosomes in the repair of peripheral nerve injury remains *** this study,we tested a comprehensive strategy for repairing long-gap(10 mm)peripheral nerve injury that combined the 3D composite conduit with human umbilical cord mesenchymal stem cell-derived *** effectiveness was evaluated by sciatic functional index,sciatic nerve compound muscle action potential recording,recovery of muscle mass,measuring the cross-sectional area of the muscle fiber,Masson trichrome staining,and transmission electron microscopy of the regenerated nerve in *** results showed that transplantation of the 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes promoted peripheral nerve regeneration and restoration of motor function,similar to autograft *** CD31-positive endothelial cells were observed in the regenerated nerve after transplantation of the loaded conduit than after transplantation of the conduit without exosomes,which may have contributed to the observed increase in axon regeneration and distal nerve ***,the use of a 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes represents a promising cell-free therapeutic option for the treatment of peripheral nerve injury.

关键词： axon growth collagen exosome human umbilical cord mesenchymal stem cells hyaluronic acid muscular atrophy nerve guidance conduits peripheral nerve regeneration

On equivalence of state-based potential games

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Science China(Information Sciences) 2024年第6期67卷 313-327页

作者： han WU Jinhuan wang Institute of Mathematics School of ScienceHebei University of Technology

In this paper, we explore state-based potential games using the semi-tensor product of ***, applying the potential equation, we derive both a necessary and sufficient condition as well as a sufficient condition to verify whether a state-based game qualifies as a potential game. Next, we present two static equivalence conditions of state-based potential games. We then delve into dynamic equivalence. We propose a criterion that allows us to identify state-based games that are dynamically equivalent to state-based potential games and share similar dynamic properties. Ultimately, we introduce the concept of state-based networked evolutionary games. We provide a necessary and sufficient condition to ensure that a state-based networked evolutionary game can be classified as a state-based potential game.

关键词： semi-tensor product of matrices state-based potential game verification equivalence state-based networked evolutionary game