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Cation-Dipole Interaction-Induced Coacervate Underwater Adhesives in Natural Seawater

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Chinese Journal of Polymer Science 2024年第7期42卷 984-991,I0009页

作者： Xu-fei Liu Chong-Rui Zhang Hua-wen Peng Qiang Zhao Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion ***,the design of adhesives for natural seawater represents challenges less ***,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural *** combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in *** instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural *** design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.

关键词： Coacervate Underwater adhesives Seawater Cation-dipole interaction

Enhancing Tropical Cyclone Intensity Estimation from Satellite Imagery through Deep Learning Techniques

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Journal of Meteorological Research 2024年第4期38卷 652-663页

作者： wen YANG Jianfang fei Xiaogang HUANG Juli DING Xiaoping CHENG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410008 Beijing Institute of Applied Meteorology Beijing 100029

This study first utilizes four well-performing pre-trained convolutional neural networks(CNNs) to gauge the intensity of tropical cyclones(TCs) using geostationary satellite infrared(IR) *** models are trained and tested on TC cases spanning from 2004 to 2022 over the western North Pacific *** enhance the models performance,various techniques are employed,including fine-tuning the original CNN models,introducing rotation augmentation to the initial dataset,temporal enhancement via sequential imagery,integrating auxiliary physical information,and adjusting *** optimized CNN model,i.e.,visual geometry group network(VGGNet),for TC intensity estimation is ultimately *** applied to the test data,the model achieves a relatively low mean absolute error(MAE) of 4.05 m s~(-1).To improve the interpretability of the model,the SmoothGrad combined with the Integrated Gradients approach is *** analyses reveal that the VGGNet model places significant emphasis on the distinct inner core region of a TC when estimating its ***,it partly takes into account the configuration of cloud systems as input features for the model,aligning well with meteorological *** several improvements made to this model's performance offer valuable insights for enhancing TC intensity forecasts through deep learning.

关键词： tropical cyclone intensity deep learning satellite imagery

Numerical simulation of liquid sloshing in a spherical tank by MPS method

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Journal of Hydrodynamics 2024年第2期36卷 232-240页

作者： Cong-yi Huang Ji-fei Wang Wei-wen Zhao De-cheng Wan Computational Marine Hydrodynamic Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Aerospace System Engineering Institute Shanghai201109China

This paper investigates the sloshing phenomena in a spherical liquid tank using the moving particle semi-implicit(MPS)method,a crucial study in fluid *** from previous research focused on rectangular or LNG tanks,this work explores the unique motion patterns inherent to spherical *** accuracy of our in-house MPS solver MLParticle-SJTU is validated against experimental data and finite volume method(FVM).And the MPS method reveals a closer alignment with experimental outcomes,which suggests that MPS method is particularly effective for modeling complex,non-linear fluid *** the fluid’s response to excitation at its natural frequency is simulated,showcasing vigorous sloshing and rotational *** analyses of the fluid motion are conducted by drawing streamline diagrams,velocity vector diagrams,and vorticity *** fluid’s motion response is explored using both time-domain and frequency-domain curves of the fluid centroid,as well as the sloshing force.

关键词： Moving particle semi-implicit(MPS)method spherical tank liquid sloshing model experiment

MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 461-483页

作者： Yang Li Jiangping Xu Yun Liu wen Zhong fei Wang School of Mechanical Engineering Jiangsu UniversityZhenjiang212016China School of Mechanical Engineering Wuhan Polytechnic UniversityWuhan430023China Shenyang Mint Company Limited Shenyang110092China

In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 *** such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously *** mitigate data races when calculating internal forces,intermediate arrays are introduced within the OpenMP *** helps ensure proper synchronization and avoid conflicts during parallel ***,in the MPI implementation,the coins are partitioned into the desired number of *** division allows for efficient distribution of computational tasks across multiple *** simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel *** results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental ***,speedup ratio and parallel efficiency are assessed for the coining process *** pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/OpenMP programming *** approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns.

关键词： Hybrid MPI/OpenMP parallel computing MPI OpenMP imprint forming

New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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维普期刊数据库

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-Lu Zhang wen-Bo He Xiu-Qin Hu Peng-fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

An ionic liquid-assisted strategy for enhanced anticorrosion of low-energy PEO coatings on magnesium–lithium alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2380-2396页

作者： You Zhang Chuping Chen Haoyue Tian Shuqi Wang Chen wen fei Chen College of New Materials and Chemical Engineering Hydrogen Energy Research CentreBeijing Institute of Petrochemical TechnologyBeijing 102617China Key Laboratory of Advanced Structure-Function Integrated Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China Beijing Spacecrafts China Academy of Space TechnologyBeijing 100190China

A low-energy plasma electrolytic oxidation(LePEO)technique is developed to simultaneously improve energy efficiency and *** liquids(1-butyl-3-methylimidazole tetrafluoroborate(BmimBF_(4)))as sustainable corrosion inhibitors are chosen to investigate the corrosion inhibition behavior of ionic liquid(ILs)during the LePEO process for LA91 magnesium-lithium(Mg-Li)*** show that the ionic liquid BmimBF_(4)participates in the LePEO coating formation process,causing an increment in coating thickness and surface *** low conductivity of the ionic liquid is responsible for the voltage and breakdown voltage increases during the LePEO with IL process(LePEO-IL).After adding BmimBF_(4),corrosion current density decreases from 1.159×10^(−4)A·cm^(−2)to 8.143×10^(−6)A·cm^(−2).The impedance modulus increases to 1.048×10^(4)Ω·cm^(−2)and neutral salt spray remains intact for 24 *** superior corrosion resistance of the LePEO coating assisted by ionic liquid could be mainly attributed to its compact and thick barrier layer and physical absorption of ionic *** ionic liquid-assisted LePEO technique provides a promising approach to reducing energy consumption and improving film performance.

关键词： Magnesium-lithium alloy Plasma electrolytic oxidation Low energy Ionic liquid Corrosion resistance

Characteristics and distribution of microstructures in high pressure die cast alloys with X-ray microtomography:A review

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China Foundry 2024年第5期21卷 427-444页

作者： Hai-dong Zhao Xue-ling Wang Qian Wan wen-hui Bai fei Liu School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China

Al and Mg alloy high pressure die castings(HPDC)are increasingly used in automotive *** microstructures in the castings have decisive effect on the casting mechanical properties,in which the microstructure characteristics are fundamental for the investigation of the microstructure-property *** the past decade,the microstructure characteristics of HPDC Al and Mg alloys,especially micro-pores andα-Fe,have been investigated from two-dimensional(2D)to threedimensional with X-ray micro-computed tomography(μ-CT).This paper provides an overview of the current understanding regarding the 3D characteristics and formation mechanisms of microstructures in HPDC alloys,their spatial distributions,and the impact on mechanical ***,it outlines future research directions for the formation and control of heterogeneous microstructures in HPDC alloys.

关键词： high pressure die casting microstructure three-dimensional characteristics distribution Al and Mg alloys

Applications of single-cell RNA sequencing in spermatogenesis and molecular evolution

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Zoological Research 2024年第3期45卷 575-585页

作者： wen-Bo Chen Meng-fei Zhang Fan Yang Jin-Lian Hua College of Veterinary Medicine Shaanxi Centre of Stem Cells Engineering&TechnologyNorthwest A&F UniversityYanglingShaanxi 712100China Key Laboratory of Livestock Biology Northwest A&F UniversityYanglingShaanxi 712100China

Spermatogenic cell heterogeneity is determined by the complex process of spermatogenesis ***,effectively revealing the regulatory mechanisms underlying mammalian spermatogenic cell development and differentiation via traditional methods is *** in technology have led to the emergence of many single-cell transcriptome sequencing protocols,which have partially addressed these *** this review,we detail the principles of 10x Genomics technology and summarize the methods for downstream analysis of single-cell transcriptome sequencing ***,we explore the role of single-cell transcriptome sequencing in revealing the heterogeneity of testicular ecological niche cells,delineating the establishment and disruption of testicular immune homeostasis during human spermatogenesis,investigating abnormal spermatogenesis in humans,and,ultimately,elucidating the molecular evolution of mammalian spermatogenesis.

关键词： Single-cell RNA sequencing(scRNA-seq) Spermatogenesis Molecular evolution Sertoli cell

Mathematical model and numerical investigation of the influence of spray drying parameters on granule sizes of mold powder

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Particuology 2024年第2期85卷 280-295页

作者： fei Zhang Youyu Lu Shaoyan Zhu Funian Han Guanghua wen Ping Tang Zibing Hou College of Materials Science and Engineering Chongqing UniversityChongqing400044China Guizhou Academy of Testing and Analysis Guizhou Academy of SciencesGuiyang550014China

In this work,the formation mechanism of the droplet-to-granule was investigated in detail based on mold powder manufacturing.A specific mathematical model of two-stage spray drying was established to describe droplet and granule motion,heat and mass transfer,and granule morphology during spray ***,the relationships between spray drying parameters(inlet temperature,atomization pres-sure,slurry mass flow rate)and the properties of the drying tower(temperature and velocity fields)and mold powder granules(temperature,evaporation rates,moisture content,and diameter)were simulated and calculated using ANSYS/Fluent *** ensure that the granule size of mold powder was controlled within the ideal range(0.2-0.6 mm)for producing granules with appropriate mechanical and metallurgical properties,the following optimum spray drying parameters were chosen based on the results of the numerical simulation:inlet temperatures,873 K;slurry atomization pressure,1.8 MPa;slurry mass flow rate,0.05 kg *** these parameters,the slurry mass flow rate has the most significant effect on granule size.

关键词： Mold powder slurry Spray drying parameters Mathematical model Numerical simulation Granule sizes