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Chinese Journal of Polymer Science 2024年第6期42卷 851-863页

作者： Yan-Jiang Li Meng-Long Hu Jun-Wen zhang Qiang Fu jie zhang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(PS)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/PS in situ microfiber composites(MFC)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(CIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the PS content reached 20%,under the combined action of PS in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers Shearfield Hybrid shish-kebab structures

ON THE EMPTY BALLS OF A CRITICAL OR SUBCRITICAL BRANCHING RANDOM WALK

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Acta Mathematica Scientia 2024年第5期44卷 2051-2072页

作者： Shuxiong zhang jie XIONG School of Mathematics and Statistics Anhui Normal UniversityWuhu241002China Department of Mathematics and SUSTech International Center for Mathematics Southern University of Science and TechnologyShenzhen518055China

Let{Z_(n)}_(n)≥0 be a critical or subcritical d-dimensional branching random walk started from a Poisson random measure whose intensity measure is the Lebesugue measure onℝ^(d).Denote by R_(n):=sup{u>0:Z_(n)({x∈ℝ^(... 详细信息

关键词： empty ball dimension branching random walk super-Brownian motion

Accelerating the solving of mechanical equilibrium caused by lattice misfit through deep learning method

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Advances in Manufacturing 2024年第3期12卷 512-521页

作者： Chen-Xi Guo Hui-Ying Yang Rui-jie zhang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083People’s Republic of China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing100083People’s Republic of China

Precipitation is a common phenomenon that occurs during heat *** is internal stress around the precipitate owing to the lattice misfit between the precipitate and *** internal stress has a significant influence not only on the precipitation kinetics but also on the material *** misfit stress can be obtained by numerically solving the mechanical equilibrium ***,this process is complex and *** developed a new approach based on deep learning to accelerate the solution *** training data were first generated by a phase-field model coupled with elastic mechanical equilibrium equations,which were solved using the finite difference *** obtained precipitate morphologies and corresponding stress distributions were input data for training the physics-informed(PI)UNet *** well-trained PI-UNet model can then be applied to predicting stress distributions with the precipitate morphology as the *** accuracy and efficiency are discussed in this *** results showed that the PI-UNet model was an appropriate approach for quickly predicting the misfit stress between the precipitate and matrix.

关键词： Precipitate Mechanical equilibrium Heat treatment Deep learning

FPGA implementation of 500-MHz high-count-rate high-time-resolution real-time digital neutron-gamma discrimination for fast liquid detectors

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Nuclear Science and Techniques 2024年第8期35卷 101-113页

作者： Hui‑Yin Shen Jing‑Long zhang jie zhang Jian‑Hang Zhou College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Southwestern Institute of Physics P.O.Box 432Chengdu 610041China

Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as *** this study,real-time neutron and gamma discrimination was implemented on a self-developed 500-Msps,12-bit digitizer,and the neutron and gamma spectra were calculated directly on an FPGA.A fast neutron flux measurement system with BC-501A and EJ-309 liquid scintillator detectors was developed and a fast neutron measurement experiment was successfully performed on the HL-2 M tokamak at the Southwestern Institute of Physics,*** experimental results demonstrated that the system obtained the neutron and gamma spectra with a time accuracy of 1 *** count rates of up to 1 Mcps,the figure of merit was greater than 1.05 for energies between 50 keV and 2.8 MeV.

关键词： Neutron-gamma discrimination Liquid scintillation detector Real-time spectrum analyzer

Stable hydrogen isoscape in precipitation generated using data fusion for East China

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Science China Earth Sciences 2024年第9期67卷 2972-2988页

作者： Jiacheng CHEN jie CHEN Xunchang John zhang Peiyi PENG State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Water System Science for Sponge City Construction Wuhan UniversityWuhan 430072China USDA-ARS Oklahoma and Central Plains Agricultural Research Center El Reno OK 73036USA Southwest Research Institute for Hydraulic and Water Transport Engineering Chongqing Jiaotong UniversityChongqing 400016China

The stable hydrogen isotope in precipitation is an effective environmental tracer for climatic and hydrologic ***,accurate and high-precision precipitation hydrogen isoscapes are currently unavailable in *** this study,a data fusion method based on Convolutional Neural Networks(CNN)is used to fuse the hydrogen isotopic composition(δ^(2)H_(p))of observations and isotope-equipped general circulation model(iGCM)simulations.A precipitation hydrogen isoscape with a temporal resolution of monthly and a spatial resolution of 50-60 km is established for East China for the 1969-2017 *** to building the isoscape,the performance of three data fusion methods(DFMs)and two bias correction methods(BCMs)is *** results indicate that the CNN fusion method performs the best with a correlation coefficient larger than 0.90 and root mean square error smaller than 10.5‰ when using observation as a *** fusion methods based on back propagation and long short-term memory neural network perform similarly,while slightly outperforming the bias correction ***,the CNN method is used to generate the hydrogen isoscape,and the temporal and spatial distribution characteristics of the hydrogen isotope in precipitation are analyzed based on this *** generated isoscape shows similar spatial and temporal distribution characteristics to *** general,the distribution pattern of δ^(2)H_(p) is consistent with the temperature effect in northern China,and consistent with the precipitation amount effect in southern *** trend of the δ^(2)H_(p) time series is consistent with that of observed precipitation and ***,the generated isoscape effectively reproduces the observations,and has the characteristics of time continuity and relative spatial regularity,which can provide valuable data support for tracking atmospheric and hydrological processes.

关键词： Precipitation Precipitation isotope General circulation model Data fusion Dataset

Succinylation modification:a potential therapeutic target in stroke

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Neural Regeneration Research 2024年第4期19卷 781-787页

作者： jie Lian Wenwu Liu Qin Hu Xiaohua zhang Department of Neurosurgery Ren Ji HospitalShanghai Jiao Tong University School of Medicine Department of Diving and Hyperbaric Medicine Naval Medical CenterNaval Medical University

Stroke is a leading cause of mortality and disability *** cell death triggered by the compromised supply of blood oxygen and glucose is one of the major pathophysiology of strokeinduced brain *** mitochondrial energy metabolism is observed minutes after stroke and is closely associated with the progression of ***,a new type of posttranslational modification,known as lysine succinylation,has been recognized to play a significant role in mitochondrial energy metabolism after ***,the role of succinylation modification in cell metabolism after stroke and its regulation are not well *** aimed to review the effects of succinylation on energy metabolism,reactive oxygen species generation,and neuroinflammation,as well as Sirtuin 5 mediated desuccinylation after *** also highlight the potential of targeting succinylation/desuccinylation as a promising strategy for the treatment of *** succinylation level is dynamically regulated by the nonenzymatic or enzymatic transfer of a succinyl group to a protein on lysine residues and the removal of succinyl catalyzed by *** evidence has suggested that succinylation can regulate the metabolic pathway through modulating the activity or stability of metabolic ***,especially Sirtuin 5,are characterized for their desuccinylation activity and have been recognized as a critical regulator of metabolism through desuccinylating numerous metabolic *** between succinylation and desuccinylation has been implicated in the pathophysiology of *** agents that enhance the activity of Sirtuin 5 have been employed to promote desuccinylation and improve mitochondrial metabolism,and neuroprotective effects of these agents have been observed in experimental stroke ***,their therapeutic efficacy in stroke patients should be validated.

关键词： mitochondria metabolism neuroprotection sirtuin 5 stroke succinylation modification

Application of ultrasonic fatigue technology in very-high-cycle fatigue testing of aviation gas turbine engine blade materials:A review

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Science China(Technological Sciences) 2024年第5期67卷 1317-1363页

作者： ZHAO JiuCheng WAN jie zhang ShiZhong YAN ChuLiang ZHAO HongWei Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin UniversityChangchun 130025China School of Mechanical&Aerospace Engineering Jilin UniversityChangchun 130025China Chongqing Research Institute of Jilin University Chongqing401120China School of Aeronautic Science and Engineering Beihang UniversityBeijing 102206China

The need for very-high-cycle fatigue(VHCF)testing up to 1010cycles of aviation gas turbine engine blade materials under combined mechanical loads and complex environments has encouraged the development of VHCF testing instrumentation and *** article begins with a comprehensive review of the existing available techniques that enable VHCF *** advances in ultrasonic fatigue testing(UFT)techniques are highlighted,containing their new capabilities and methods for single load,multiaxial load,variable amplitude fatigue,and combined cycle *** techniques for conducting UFT in high-temperature,humid environments,and corrosive environments are *** developments in mechanical loading and environmental building techniques provide the possibility of laboratory construction for real service conditions of blade *** techniques that can be used for in situ monitoring of VHCF damage are *** issues in the UFT field are presented,and countermeasures are ***,the existing problems and future trends in the field are briefly described.

关键词： aviation gas turbine engine blade materials ultrasonic fatigue very-high-cycle fatigue high-temperature complex stress in situ testing

Process intensification for the synthesis and purification of battery-grade Li_(2)CO_(3)with microfluidics

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Particuology 2024年第7期90卷 106-117页

作者： Haodu Li jie zhang Lin Dai Le Du Jiqin Zhu The State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Battery-grade lithium carbonate(Li_(2)CO_(3))with a purity of higher than 99.5 wt%is of great importance as a high value-added lithium ***,influences of different reaction systems and process control on product purity remain ***,a membrane dispersion microreactor was used to enhance the mass transfer of preparation and purification processes in homogeneous and heterogeneous *** systems of Na_(2)CO_(3)–LiCl,NH_(4)HCO_(3)–LiCl,and NH_(3)·H_(2)O−CO_(2)−LiCl,CO_(2)purification based on carbonation and decomposition were *** Li_(2)CO_(3)purity was increased by the improvement of mixing *** carbonation time was reduced by 62.5%and 58.3%for the NH_(3)·H_(2)O−CO_(2)and CO_(2)purification systems,*** the two ammonia-based systems,Li_(2)CO_(3)particles with a purity of 99.7–99.8 wt%were one-step prepared with a size of 3–5μm,which also met the requirement of the battery-grade *** purity was further increased to 99.9 wt%by CO_(2)purification and LiHCO_(3)*** investigation could provide a feasible alternative for the controllable preparation of battery-grade Li_(2)CO_(3)in one or multiple steps.

关键词： Microfluidics Battery grade Li_(2)CO_(3) Process intensification High purity

Distributed power conditioning unit of large-scale space solar power station

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Chinese Journal of Aeronautics 2024年第8期37卷 421-434页

作者： Xintong LI Jianwei MI Yiqun zhang Guanheng FAN jie DU School of Mechano-electronic Engineering Xidian UniversityXi’an 710071China Shaanxi Key Laboratory of Space Solar Power Station System Xidian UniversityXi’an 710071China Academy of Advanced Interdisciplinary Research Xidian UniversityXi’an 710071China

In this paper,a multi-bus distributed Power Conditioning Unit(PCU)is proposed for the Space Solar Power Station with large scale photovoltaic(PV)array and power levels reaching MW *** this unit,there are multiple independent PV *** each PV array,there are multiple independent PV *** this paper,a V-P droop control method with adaptive droop coefficient is proposed,which modifies the droop intercept based on the bus voltage deviation and the power per unit value of the PV *** method ensures the accuracy of bus voltage and achieves proportional distribution of power between PV arrays based on the proposed topology structure in this *** the load changes or the output power of the PV array fluctuates,this method can ensure that power is distributed *** principle and control method of the proposed droop control method is analyzed in this *** effectiveness of the method is verified through MATLAB/Simulink simulation and *** and experimental results show that the proposed method can achieve power distributed proportionally when load changes and PV output power fluctuates,reduce bus voltage error caused by line impedance and differences in rated power of different PV arrays,and improve the performance of PV power generation system applied to space.

关键词： Space Solar Power Station Photovoltaics Droop control DC confluence Power conditioning unit

Optimizing extractants selection for efficient separation of phenols and nitrogen-containing heteroaromatics using hydrogen bond interaction strategies

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Chinese Journal of Chemical Engineering 2024年第4期68卷 43-52页

作者： Pengzhi Bei Rui zhang jie Feng Antony Rajendran Wenying Li State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China Department of Chemistry Mepco Schlenk Engineering College(Autonomous)Sivakasi 626005India

Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been *** environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation *** quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and N-heteroaromatics *** article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic *** showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing *** ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical ***,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and N-containing aromatic compounds.

关键词： Deep eutectic solvents Hydrogen bond Ionic liquids Separation Solvents Structural characteristics