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Research in Astronomy and Astrophysics 2024年第8期24卷 147-156页

作者： Xuan Zhang Jin-zhong liu Le-Tian Wang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

In this work,we report observations of three comets:38P/Stephan-Oterma,64P/Swift-Gehrels,and C/2017 M4(ATLAS),conducted with the Nanshan one-meter wide-field telescope in 2018 August and November,and *** extracted morphological features through image enhancement techniques and calculated the dust activity parameter,Afρ,along with dust mass loss rates and coma color indices using broadband photometric *** morphological analysis uncovered a spectrum of dust characteristics among the observed comets,ranging from a significant twisted structure in comet 38P/Stephan-Oterma’s coma to the regular coma envelope surrounding comet 64P/*** Afρvalues varied between 148.8±0.3 cm for 64P/Swift-Gehrels and1118.5±6.2 cm for C/2017 M4(ATLAS)(measured within a reference aperture radius ofρ=6″),indicating a range from moderate to high activity *** mass loss rates were estimated from 328.1 kg s^(-1)for comet 64P/Swift-Gehrels to 1395.5 kg s^(-1)for comet C/2017 M4(ATLAS).The color indices of comets 38P/Stephan-Oterma and C/2017 M4(ATLAS)closely resemble the average colors of active short-period comets and active longperiod comets,*** contrast,64P/Swift-Gehrels exhibits a significantly bluer hue than typical Jupiter family comets.

关键词： comets general-comets individual(38P/Stephan-Oterma,64P/Swift-Gehrels,C/2017 M4(ATLAS))-techniques photometric

GLP-1 receptor agonists and myocardial metabolism in atrial fibrillation

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Journal of Pharmaceutical Analysis 2024年第5期14卷 653-665页

作者： Jiani zhong Hang Chen Qiming liu Shenghua Zhou Zhenguo liu Yichao Xiao Department of Cardiovascular Medicine Second Xiangya HospitalCentral South UniversityChangsha410011China Xiangya School of Medicine Central South UniversityChangsha410008China Center for Precision Medicine and Division of Cardiovascular Medicine Department of MedicineSchool of MedicineUniversity of MissouriColumbiaMO65211USA

Atrial fibrillation(AF)is the most common cardiac *** medical conditions,including hypertension,diabetes,obesity,sleep apnea,and heart failure(HF),increase the risk for *** have unique metabolic characteristics to maintain adenosine triphosphate *** changes occur in myocardial metabolism in ***-like peptide-1 receptor agonists(GLP-1RAs)have been used to control blood glucose fluctuations and weight in the treatment of type 2 diabetes mellitus(T2DM)and ***-1RAs have also been shown to reduce oxidative stress,inflammation,autonomic nervous system modulation,and mitochondrial *** article reviews the changes in metabolic characteristics in cardiomyocytes in *** the clinical trial outcomes are unsatisfactory,the findings demonstrate that GLP-1 RAs can improve myocardial metabolism in the presence of various risk factors,lowering the incidence of AF.

关键词： Atrial fibrillation Glucagon-like peptide-1 receptor agonists Metabolism

Super-high bed sintering for iron ores:behaviors,causes and solutions of horizontal segregation on strand

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Journal of Iron and Steel Research International 2024年第7期31卷 1590-1596页

作者： Liang-ping Xu Hui-bo liu zhong-lin Dong Qiang zhong Yu-chao Zhao Guang-hui Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Horizontal segregation has been a constraint to the development and application of super-high bed *** eliminate the horizontal segregation of super-high bed sintering,several typical sintering machines were sampled and analyzed,and theoretical calculation was made to compare the bed depth and their differences in different areas within the mixture ***,solutions were proposed and applied to a 265 m^(2) sintering *** results showed that the horizontal seg-regation of the 265 m^(2) sintering machine was dominated by particles larger than 8 mm with horizontal segregation degree of 0.48,while 360 and 550 m^(2) sintering machines were affected by 5-8 mm and 1-3 mm particles with horizontal segregation degree of 0.27 and 0.31,*** analysis indicated the different segregation distribution results from the matching of the bed depth of each area within the mixture ***,the horizontal segregation degree not larger than 0.06 was achieved by optimizing the time parameters and the division of three zones on the 265 m^(2) sintering machine.

关键词： Super-high bed sintering Horizontal segregation Feeder Particle distribution Agglomeration

Super-high bed sintering for iron ores: inhomogeneous phenomena and its mechanism during mineralizing

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Journal of Iron and Steel Research International 2024年第8期31卷 1850-1860页

作者： Hui-bo liu Liang-ping Xu Xi-duan Yang zhong-lin Dong Qiang zhong Guang-hui Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous *** inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were *** results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,*** the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 *** and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm *** heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel *** inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid *** inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing *** mineralizing condition is the key for homogeneous super-high bed sintering.

关键词： Iron ore Super-high bed sintering Mineralization Material segregation Heat accumulation

Nonstationary channel model of reentry plasma sheath for spacecraft: Overview, parameter estimation, and perspective

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Chinese Journal of Aeronautics 2024年第10期37卷 26-49页

作者： Lei SHI Zongyuan liu Weimin bao Bo YAO Yifan WANG Xiaoping LI Yanming liu Fangyan LI School of Aerospace Science and Technology Xidian UniversityXi’an 710126China Key Laboratory of Equipment Efficiency in Extreme Environment Ministry of EducationXi’an 710126China China Aerospace Science and Technology Corporation Beijing 100048China

The Tracking,Telemetering,and Command(TT&C)communication of spacecraft faces severe limitations during *** Electromagnetic(EM)propagation channel is influenced by changes in the flight state and fluid *** addition to the high-speed spatial channel,the Plasma Sheath Channel(PSC),which covers the surface of spacecraft,exhibits unique nonstationary and highly dynamic time-varying *** absence of a channel model for the reentry process of spacecraft negatively impacts the quality evaluation and system design of TT&C *** paper summarizes the methods for nonstationary PSC modeling,involving calculation methods for attenuation and phase shift in the channel,as well as a multistate nonstationary channel statistical model based on a hidden Markov ***,the correlation between amplitude variation and phase variation with electron density is *** paper also provides statistical characteristics of the channel and channel parameters at typical frequencies in the S/C/X/Ka *** findings serve as a reference for the design and evaluation of TT&C communication systems for reentry ***,the paper discusses the prospects of various aspects related to the channel characteristics and modeling of spacecraft PSCs in the shortwave and terahertz/laser bands,as well as the potential challenges in cross-domain spacecraft channel sensing and prediction.

关键词： Spacecraft Plasma sheaths Electromagnetic wave transmission Communication channels Channel estimation

Regulating solid electrolyte interphase film on fluorinedoped hard carbon anode for sodium-ion battery

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Carbon Energy 2024年第6期6卷 200-215页

作者： Cuiyun Yang Wentao zhong Yuqiao liu Qiang Deng Qian Cheng Xiaozhao liu Chenghao Yang Guangzhou Key Laboratory for Surface Chemistry of Energy Materials New Energy Research InstituteSchool of Environment and EnergySouth China University of TechnologyGuangzhouChina

For the performance optimization strategies of hard carbon,heteroatom doping is an effective way to enhance the intrinsic transfer properties of sodium ions and electrons for accelerating the reaction ***,the previous work focuses mainly on the intrinsic physicochemical property changes of the material,but little attention has been paid to the resulting interfacial regulation of the electrode surface,namely the formation of solid electrolyte interphase(SEI)*** this work,element F,which has the highest electronegativity,was chosen as the doping source to,more effectively,tune the electronic structure of the hard *** effect of F-doping on the physicochemical properties of hard carbon was not only systematically analyzed but also investigated with spectroscopy,optics,and in situ characterization techniques to further verify that appropriate F-doping plays a positive role in constructing a homogenous and inorganic-rich SEI *** experimentally demonstrated link between the electronic structure of the electrode and the SEI film properties can reframe the doping optimization strategy as well as provide a new idea for the design of electrode materials with low reduction kinetics to the *** a result,the optimized sample with the appropriate F-doping content exhibits the best electrochemical performance with high capacity(434.53 mA h g^(-1)at 20mA g^(-1))and excellent rate capability(141 mAh g^(-1)at 400 mA g^(-1)).

关键词： F-doping hard carbon reduction kinetics sodium-ion batteries solid electrolyte interphase film

Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-Jing Zhao Jing Wang zhong-Yang Qi Hui-Qing liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

Effect of solvent on the initiation mechanism of living anionic polymerization of styrene:A computational study

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Chinese Journal of Chemical Engineering 2024年第5期69卷 135-142页

作者： Shen Li Yin-Ning Zhou zhong-Xin liu Zheng-Hong Luo School of Chemical Engineering and Technology Hainan UniversityHaikou 570228China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

For living anionic polymerization(LAP),solvent has a great influence on both reaction mechanism and *** this work,by using the classical butyl lithium-styrene polymerization as a model system,the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory(DFT)calculations and kinetic *** terms of mechanism,it is found that the stronger the solvent polarity,the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent ***,we also found that the stronger the solvent polarity,the higher the monomer initiation energy barrier and the smaller the initiation rate ***,initiation is more favorable at lower temperatures based on the calculated results ofΔG_(TS).Finally,the kinetic characteristics in different solvents were further examined by kinetic *** is found that in benzene and n-pentane,the polymerization rate exhibits first-order ***,slow initiation and fast propagation were observed in tetrahydrofuran(THF)due to the slow free ion formation rate,leading to a deviation from first-order kinetics.

关键词： Living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling

A reputation-based blockchain scheme for sustained carbon emission reduction

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Science China(Information Sciences) 2024年第5期67卷 329-330页

作者： Lixiao ZHOU Changbing TANG Zheng bao Yang liu Xinghuo YU College of Physics and Electronics Information Engineering Zhejiang Normal University School of Computer Science and Technology Zhejiang Normal University School of Mathematical Sciences Zhejiang Normal University School of Engineering RMIT University

Climate change is a global issue that necessitates collective responsibility from all nations. Recently, a blockchainenabled emission trading scheme(ETS) has been proposed for reducing carbon emissions to overcome the drawbacks of centralized methods [1, 2]. However, existing consensus protocols in blockchain have not been well prepared for low energy consumption and high incentive compatibility [3],which is contrary to the low carbon goal of ETS.

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Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway

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Chinese Journal of Integrative Medicine 2024年第4期30卷 299-310页

作者： liu Xiao-rong LI Shuo-fu MEI Wen-ya liu Xiang-dan ZHOU Ri-bao College of Pharmacy Hunan University of Chinese MedicineChangsha(410208)China Department of Orthopaedics The First Hospital of Hunan University of Chinese MedicineChangsha(410007)China

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).Methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(MMP2)or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS ***-FLS viability,migration,and invasion were ***,a collagen-induced arthritis(CIA)rat model was *** were randomly divided to sham,CIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,*** index was calculated and synovial tissue inflammation was determined in CIA *** levels of MMP2,MMP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRC,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(CREB),were detected in RA-FLS and synovial *** docking was also used to analyze the binding of isorhamnetin to *** In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(P<0.05).Isorhamnetin downregulated the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1βin RA-FLS(P<0.05).The overexpression of either MMP2 or MMP9 reversed isorhamnetin-inhibited RA-FLS migration and invasion,as well as the levels of TNF-α,IL-6,and IL-1β(P<0.05).Furthermore,isorhamnetin bound to SRC and reduced the phosphorylation of SRC,ERK,and CREB(P<0.05).SRC overexpression reversed the inhibitory effect of isorhamnetin on RA-FLS viability,migration and invasion,as well as the negative regulation of MMP2 and MMP9(P<0.05).In in vivo studies,isorhamnetin decreased arthritis index scores(P<0.05)and alleviated synovial *** reduced the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRC,ERK,and CRE

关键词： rheumatoid arthritis isorhamnetin SRC/ERK/CREB matrix metalloproteinase