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Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU Lin LI Xue XIE jun dong Ming School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China School of Optical Information and Energy Engineering Wuhan Institute of TechnologyWuhan 430205China School of Energy and Environment Shenyang Aerospace UniversityShenyang 110136China

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method(LES-DEM)*** validity of the LES approach was verified by comparison with available direct numerical simulation(DNS)*** adopted the Johnson-Kendall-Roberts(JKR)contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters(d_(p)=2-20μm)in the laminar and transition of shear layer(TrSL)flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise(y-direction).With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： microparticle particle agglomeration discrete element method large eddy simulation

维普期刊数据库

Cubature Kalman Fusion Filtering Under Amplify-and-Forward Relays With Randomly Varying Channel Parameters

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 356-368页

作者： Jiaxing Li Zidong Wang jun Hu Hongli dong Hongjian Liu the Department of Applied Mathematics Harbin University of Science and Technology IEEE the Department of Computer Science Brunel University London the School of Automation Harbin University of Science and Technology the Artificial Intelligence Energy Research Institute Northeast Petroleum University the Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum University the National Key Laboratory of Continental Shale Oil of China Northeast Petroleum University the Key Laboratory of Advanced Perception and Intelligent Control of High-End Equipment Ministry of Education Anhui Polytechnic University the School of Mathematics and Physics Anhui Polytechnic University

In this paper, the problem of cubature Kalman fusion filtering(CKFF) is addressed for multi-sensor systems under amplify-and-forward(AaF) relays. For the purpose of facilitating data transmission, AaF relays are utilized to regulate signal communication between sensors and filters. Here, the randomly varying channel parameters are represented by a set of stochastic variables whose occurring probabilities are permitted to exhibit bounded uncertainty. Employing the spherical-radial cubature principle, a local filter under AaF relays is initially constructed. This construction ensures and minimizes an upper bound of the filtering error covariance by designing an appropriate filter gain. Subsequently, the local filters are fused through the application of the covariance intersection fusion rule. Furthermore, the uniform boundedness of the filtering error covariance's upper bound is investigated through establishing certain sufficient conditions. The effectiveness of the proposed CKFF scheme is ultimately validated via a simulation experiment concentrating on a three-phase induction machine.

关键词： Amplify-and-forward (AaF) relays covariance intersection fusion cubature Kalman filtering multi-sensor systems uniform boundedness

Travelling characteristics of road vehicles on single-level rail-cum-road bridge under the dynamic and aerodynamic impact of travelling trains

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 235-256页

作者： He Jiajun Lu jun Guo Wei dong Lianjie Bai Xue Li Yongle Southwest Municipal Design&Research Institute of China Chengdu 610299China Southwest Jiaotong University Chengdu 610031China

Aerodynamic and dynamic interference from trains is a key issue of concern for the safety of road vehicles travelling on single-level rail-cum road *** on the wind-road vehicle-train-bridge(WRTB)coupled vibration system developed herein,this study examines the dynamic characteristics when road vehicles meet trains in this *** influence of load combination,vehicle type and vehicle location is analyzed.A method to obtain the aerodynamic load of road vehicles encountering the train at an arbitrary wind speed is *** results show that due to the windproof facilities and the large line distance between the railway and highway,the aerodynamic and dynamic influence of trains on road vehicles is slight,and the vibration of road vehicles depends on the road *** the road vehicles discussed,the bus is the easiest to rollover,and the truck-trailer is the easiest to *** with the aerodynamic impact of trains,the crosswind has a more significant influence on road *** first peak/valley value of aerodynamic loads determines the maximum dynamic response,and the quick method is optimized based on this *** cases show that the optimized method can produce conservative results and can be used for relevant research or engineering applications.

关键词： single-level rail-cum-road bridge vehicle-bridge coupled vibration dynamic characteristic aerodynamic impact road vehicle

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Effect of h-BN rods on high-temperature properties of alumina-carbon refractory

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Journal of Iron and Steel Research International 2025年第1期32卷 115-128页

作者： Ya-ge Li Shuai-bing Wu Feng Liang Zhong Huang Tu Long Long dong jun-yi Lv Hong-juan Duan Biao Wen Yong Liu Hai-jun Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Sinosteel Luoyang Institute of Refractories Research Co. Ltd.Luoyang471039HenanChina

h-BN rods modified low-carbon alumina-carbon(Al_(2)O_(3)-C)refractories were prepared,and the effect of h-BN rod addition on the high-temperature properties was investigated and compared with commercial h-BN flake,carbon black,and carbon nanotubes *** results demonstrated that Al_(2)O_(3)-C refractories containing h-BN rods exhibited optimal high-temperature service performances,including 25%higher hot modulus of rupture,21.3%higher thermal shock strength residual ratio,20.9%lower in oxidation and 44.3%less in slag corrosion,compared to the counterpart specimens without ***,benefiting from the synergistic enhancement of the rod-like h-BN and in-situ generated SiC whiskers,the high-temperature service performances of h-BN rods containing specimens outperformed counterpart specimens containing commercial h-BN flake,carbon black,and carbon nanotubes,respectively.

关键词： Al_(2)O_(3)-C refractory h-BN rod Microstructure High-temperature service performance

Development of Gravity Theories in the View of TRAPPIST-1e

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Research in Astronomy and Astrophysics 2025年第1期25卷 143-161页

作者： Nan Wang Lu-Yao Lu Hui-Gen Liu An-dong Chen Tiger Lu Ao-Ran Cui jun-Kai Wang Marine Science and Technology College Zhejiang Ocean University Key Laboratory of Modern Astronomy and Astrophysics Ministry of Education Zhoushan Astronomical Society School of Astronomy and Space Science Nanjing University Department of Astronomy Yale University Kuang Yaming Honors School Nanjing University School of Physics Nanjing University

Contrary to the solar system, most exoplanet systems detected hitherto are close-in and compact. One typical system is TRAPPIST-1, which has seven nearly co-planar terrestrial planets all within the orbit of Mercury,including three in the habitable zone. To evaluate the differences in developing sophisticated gravity theories from the solar system, we use N-body integrations to simulate ephemeris and reproduce some important astronomy phenomena observed on the potentially habitable planet TRAPPIST-1e. Retrograde motions of other planets last1–2 orders of magnitude shorter than in the solar system, but occur much more frequently. Transit events of all inner planets can be observed steadily. Except for Kepler's first law, which is hard to notice for low eccentricities of planets, the other two laws can then be precisely verified in 102days, because the areas swept by planets vary by?0.01% and the observed semimajor axes and periods result in constants with theoretical and observation accuracies both ?2%. However, the mean motion correlation implies that the Great Inequality is not always apparent between one pair of planets like Jupiter and Saturn. Furthermore, general relativity can hardly be discovered because it gives rise to perihelion precession of inner planets only ～0.1% of gravity precession, dozens of times smaller than Mercury. Our results support the possibility of developing part of gravity theories by potential exo-civilizations in compact systems like TRAPPIST-1.

关键词： ephemerides extraterrestrial intelligence gravitation planets and satellites: terrestrial planets

Hawking radiation and Page curve of regular black holes

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Chinese Physics B 2025年第2期34卷 178-187页

作者： Chen-Yang dong Li-jun Tian Department of Physics Shanghai UniversityShanghai 200444China

We discuss the information paradox and its implications for regular black holes. Our primary focus is on Page curve using the island treatment and analyzing relevant parameters like Page time and scrambling time. Calculations without considering the island show that the entanglement entropy increases linearly and continues to infinity. When we consider the generalized entropy, we find that the island extends just beyond the horizon, leading to a constant entanglement ***, we find that in the early stages, the island never forms, regardless of the charge and mass configuration of the black hole.

关键词： black holes AdS/CFT correspondence Page curve

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin Zhang Wei-Wei Wang Mei-Qian Fu Hong-Bing Mo Wei-dong Yu Chao Liu jun Yan College of Chemistry and Chemical Engineering Central South University junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Single-atom“surgery”on chiral all-dialkynyl-protected superatomic silver nanoclusters

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Science Bulletin 2025年第3期70卷 365-372页

作者： Chengkai Zhang Wei-Dan Si Wei-dong Tian Wan-jun Xiao Zhi-Yong Gao Zhi Wang Chen-Ho Tung Di Sun School of Chemistry and Chemical Engineering State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

The manipulation of single atom within the metallic kernel of nanoclusters has attracted considerable attention due to its potentials to elucidate kernel-based structure-property relationships at the single-atom ***,new-designed chiral bialkynyl ligands,have been chosen as protective agents to isolate two pairs of 8-electron superatomic silver nanoclusters,R/S-Ag39 and R/S-Ag40.X-ray diffraction analysis reveals that Ag39 and Ag40 with the same number of chiral ligands,possess a closely analogous silver skeleton but a single-atomic *** incorporation of an extra Ag40th atom into Ag40 evokes two significant changes of structure and property compared to Ag39:(i)a reduction in the symmetry of the entire nanocluster,resulting in an enhancement of kernel-related asymmetry g-factor;(ii)a regulation of the transitions(1P→1D and Ligand(π)→1D)of excited state,leading to a second near-infrared(NIR-II,1000-1700 nm)phosphorescent emission red-shift from 1088 to 1150 *** work not only provides vital insights into the relationship between structures and ground/excited states chiroptical activities at the single-atom level,but also presents bialkynyl as a promising stabilizing agent for building superatomic metal nanoclusters.

关键词： Single atom manipulation Chiral bialkynyl ligands Superatomic silver nanoclusters NIR-Il phosphorescence

Machine learning model-based prediction of postpancreatectomy acute pancreatitis following pancreaticoduodenectomy:A retrospective cohort study

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World Journal of Gastroenterology 2025年第8期31卷 9-23页

作者： Ji-Ming Ma Peng-Fei Wang Liu-Qing Yang jun-Kai Wang Jian-Ping Song Yu-Mei Li Yan Wen Bing-jun Tang Xue-dong Wang Hepatopancreatobiliary Center Beijing Tsinghua Changgung HospitalBeijing 102218China Department of Information Administration Beijing Tsinghua Changgung HospitalBeijing 102218China Department of Radiology Beijing Tsinghua Changgung HospitalBeijing 102218China Organ Transplantation Qilu HospitalCheeloo College of MedicineShandong UniversityJinan 250012Shandong ProvinceChina Department of Otorhinolaryngology Xiangyang No.1 People’s HospitalXiangyang 441000Hubei ProvinceChina

BACKGROUND The International Study Group of Pancreatic Surgery has established the defi-nition and grading system for postpancreatectomy acute pancreatitis(PPAP).There are no established machine learning models for predicting PPAP following pancreaticoduodenectomy(PD).AIM To explore the predictive model of PPAP,and test its predictive efficacy to guide the clinical *** Clinical data from consecutive patients who underwent PD between 2016 and 2024 were retrospectively *** analysis of PPAP risk factors was performed,various machine learning algorithms[logistic regression,random forest,gradient boosting decision tree,extreme gradient boosting,light gradient boosting machine,and category boosting(CatBoost)]were utilized to develop predictive *** feature elimination was employed to select several variables to achieve the optimal machine *** The study included 381 patients,of whom 88(23.09%)developed *** patients exhibited a significantly higher incidence of postoperative pancreatic fistula(55.68%vs 14.68%,P<0.001),grade C postoperative pancreatic fistula(9.09%vs 1.37%,P=0.001).The CatBoost algorithm outperformed other algorithms with a mean area under the receiver operating characteristic curve of 0.859[95%confidence interval(CI):0.814-0.905]in the training cohort and 0.822(95%CI:0.717-0.927)in the testing *** to shapley additive explanations analysis,pancreatic texture,main pancreatic duct diameter,body mass index,estimated blood loss,and surgery time were the most important variables based on recursive feature *** CatBoost algorithm based on selected variables demonstrated superior performance,with an area under the receiver operating characteristic curve of 0.837(95%CI:0.788-0.886)in the training cohort and 0.812(95%CI:0.697-0.927)in the testing *** We developed the first machine learning-based predictive model for PPAP following *** predictive model can assist surgeons in an

关键词： Pancreaticoduodenectomy Postoperative complication Acute pancreatitis Machine learning Predictive value