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Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

作者： Gu-jun Chen Sheng-ping he College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

Single argon bubble dynamics in liquid steel under Ruhrstahl-heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

Poly(3-hexylthio) thiophene Field-effect Transistor Device Performance: Impact of the Content of hexylthio Side Chain on Backbone

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Chinese Journal of Polymer Science 2024年第1期42卷 14-23,I0005页

作者： Hao-Yu Liu Lian-he Han Ling-Wei Kong Li-ping Zhu Xiao-Lan Qiao Mei-fang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.

关键词： Conjugated polymer Polythiophene Noncovalent interaction Molecular aggregation Organic field-effect transistor

Numerical investigation on thermomechanical behavior of alumina–calcium hexaluminate refractories for purging plug

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Journal of Iron and Steel Research International 2024年第2期31卷 389-400页

作者： Li-ping Pan Ya-wei Li fang-guan Tan Yi-chen Chen Yang-fan Xu Zhu he Bao-kuan Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan430081HubeiChina

Alumina–spinel refractories used in slit-type purging plugs are susceptible to cross-sectional damage,resulting in a serious mismatch between their service life and that of ***–calcium hexaluminate refractories have gradually become the new trend in purging plug materials with the development of refining *** thermomechanical damage of slit-type purging plugs with alumina–calcium hexaluminate refractory was investigated by the thermo-solid coupling *** with the polynomial fitting and design of experiments methods,the influence of thermophysical parameters on temperature and thermal stress of alumina–calcium hexaluminate refractories for purging plugs was systematically *** results show that the maximum thermal stress of the purging plugs appears during the stages of steel transporting and stirring,and the vulnerable parts are located above Y=0.323 *** thermal conductivity and the coefficient of thermal expansion of the material are the most sensitive parameters to the temperature and thermal stress inside the structure,*** addition of more calcium hexaluminate can relieve the stress concentration and large deformation around the ***,when the content of calcium hexaluminate is 47 wt.%and in the form of aggregate-binder,the temperature and thermal stress distribution inside the refractory are optimal,which can effectively improve the service life of the slit-type purging plug.

关键词： Purging plug Thermomechanical damage Refractory Design of experiments method Stress

Improved Subsynchronous Oscillation Parameter Identification with Synchrophasor Based on Matrix Pencil Method in Power Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 22-33页

作者： Xiaoxue Zhang fang Zhang Wenzhong Gao Jinghan he the School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China the Department of Electrical and Computer Engineering University of DenverDenverUSA

The subsynchronous oscillations(SSOs)related to renewable generation seriously affect the stability and safety of the power *** realize the dynamic monitoring of SSOs by utilizing the high computational efficiency and noise-resilient features of the matrix pencil method(MPM),this paper propos es an improved MPM-based parameter identification with syn *** MPM is enhanced by the angular frequency fitting equations based on the characteristic polynomial coeffi cients of the matrix pencil to ensure the accuracy of the identi fied parameters,since the existing eigenvalue solution of the MPM ignores the angular frequency conjugation constraints of the two fundamental modes and two oscillation ***,the identification and recovery of bad data are proposed by uti lizing the difference in temporal continuity of the synchropha sors before and after noise *** proposed parameter identification is verified with synthetic,simulated,and actual measured phase measurement unit(PMU)*** with the existing MPM,the improved MPM achieves better accuracy for parameter identification of each component in SSOs,better real-time performance,and significantly reduces the effect of bad data.

关键词： Subsynchronous oscillations(SSOs) synchrophasor parameter identification matrix pencil method bad data

Channel assignment and power allocation for throughput improvement with PPO in B5G heterogeneous edge networks

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Digital Communications and Networks 2024年第1期10卷 109-116页

作者： Xiaoming he Yingchi Mao Yinqiu Liu ping ping Yan Hong Han Hu The College of Computer and Information Hohai UniversityNanjingChina The Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjing China The School of Computer Science and Engineering Nanyang Technological UniversitySingapore The College of Textile and Clothing Engineering Soochow UniversitySuzhouChina The College of Internet of Things Nanjing University of Posts and TelecomurunicationsNanjingChina

In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver uses interference ***,uncoordinated radio resource allocation can reduce system throughput and lead to user inequity,for this reason,in this paper,channel allocation and power allocation problems are formulated to maximize the system sum rate and minimum user achievable *** the construction model is non-convex and the response variables are high-dimensional,a distributed Deep Reinforcement Learning(DRL)framework called distributed Proximal Policy Optimization(PPO)is proposed to allocate or assign ***,several simulated agents are trained in a heterogeneous environment to find robust behaviors that perform well in channel assignment and power ***,agents in the collection stage slow down,which hinders the learning of other ***,a preemption strategy is further proposed in this paper to optimize the distributed PPO,form DP-PPO and successfully mitigate the straggler *** experimental results show that our mechanism named DP-PPO improves the performance over other DRL methods.

关键词： B5G heterogeneous edge networks PPO Channel assignment Power allocation Throughput

Assessment on eco-environmental quality of the Yellow River Basin by considering desertification index

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Journal of Mountain Science 2024年第10期21卷 3275-3292页

作者： AN Min MENG Fan he Weijun XUE fang SONG Mengfei XIE ping WANG Bei College of Economics&Management China Three Gorges UniversityYichang 443002China

Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in ***,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have paid limited attention to the indicator of *** is of great significance to incorporate the desertification index into the spatiotemporal assessment of the EEQ in the YRB in order to protect the ecological environment in the *** this study,based on multi-source remote sensing data from 91 cities in the YRB,this article proposes a desertification remote sensing ecological index(DRSEI)model,which builds upon the traditional Remote Sensing Ecological Index(RSEI)model,to analyze the spatiotemporal changes in the EEQ in the YRB from 2001 to ***,using the geographic detector(GD),and geographically and temporally weighted regression(GTWR)model,the study assesses the impact of human and natural factors on the EEQ in the *** research findings indicate that:(1)Compared to the traditional RSEI,the improved DRSEI shows a decreasing trend in the evaluation results of the *** the 24 cities,the change in DRSEI exceeds 0.05 compared to RSEI,accounting for 26.37%of the *** remaining 67 cities have changes within a range of less than 0.05,accounting for 73.63%of the YRB.(2)The results of the GD for individual and interactive effects reveal that rainfall and elevation have significant individual and interactive effects on the ***,after the interaction with natural factors,the explanatory power of human factors gradually increases over *** spatial heterogeneity results of GTWR demonstrate that rainfall has a strong direct positive impact on the EEQ,accounting for 98.90%of the influence,while temperature exhibits a more pronounced direct inhibitory effect,accounting for 76.92%of the *** activities have a strong negative impact on the EEQ and a weak positive impact.

关键词： Ecological environment quality Desertification index Desertification remote sensing ecological index Driving factors Yellow River Basin

P2P Energy Trading Considering Prosumer Preference and System Risk

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1179-1194页

作者： Xinyu he ping Dong Mingbo Liu Xuewei Huang Wenli Deng Ruijin he School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China IEEE

As an important means of mobilizing demand-side resources,peer-to-peer(P2P)energy trading has drawn more and more attention from *** paper constructs a P2P energy trading framework considering prosumers’trading partner preferences(TPPs)and system *** first,we build the P2P trading models of prosumers equipped with different distributed energy resources(DERs),and TPP ***,to solve the established energy trading problem,a fully distributed double-consensus alternating direction method of multipliers(DC-ADMM)is proposed,which can achieve transaction consensus when considering market players’***,a risk-based security constrained economic dispatch(RBSCED)model based on AC power flow is established for the first time,by which a distribution system operator(DSO)checks system security and obtains risk-based locational marginal prices(RLMPs).Moreover,double-regulated price signals related to RLMPs which contain grid utilization prices(GUPs)and DSO’s retail prices realize management of players’*** the end,the proposed method is applied to an IEEE33 bus distribution *** show the proposed method effectively reduces system risk and ensures secure operation of system without direct management.

关键词： Double-consensus ADMM grid utilization price price signal risk-based locational marginal price trading partner preference

Research on thermal insulation materials properties under HTHP conditions for deep oil and gas reservoir rock ITP-Coring

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Petroleum Science 2024年第4期21卷 2625-2637页

作者： Zhi-Qiang he he-ping Xie Ling Chen Jian-ping Yang Bo Yu Zi-Jie Wei Ming-Zhong Gao State Key Laboratory of Intelligent Construction and healthy Operation and Maintenance of Deep Underground Engineering College of Water Resource and Hydropower Sichuan University Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green Energy College of Civil and Transportation Engineering Shenzhen University School of Mechanical Engineering Sichuan University College of Polymer Science and Engineering Sichuan University

Deep oil and gas reservoirs are under high-temperature conditions, but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability, resulting in distorted resource assessments. The development of in situ temperaturepreserved coring(ITP-Coring) technology for deep reservoir rock is urgent, and thermal insulation materials are key. Therefore, hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials) were proposed as thermal insulation materials. The materials properties under coupled hightemperature and high-pressure(HTHP) conditions were tested. The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased; additionally,increasing temperature accelerated the process. High temperatures directly caused the thermal conductivity of the materials to increase; additionally, the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity. High temperatures weakened the matrix, and high pressures destroyed the HGM, which resulted in a decrease in the tensile mechanical properties of the materials. The materials entered the high elastic state at 150.C, and the mechanical properties were weakened more obviously, while the pressure led to a significant effect when the water absorption was above 10%. Meanwhile, the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86% at 100.C and 100 MPa, respectively, which meet the application requirements of the self-designed coring device. Finally, K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100.C and 100 MPa. To further improve the materials properties, the interface layer and EP matrix should be optimized. The results can provide references for the optimization and engineering application of materials and thus technical su

关键词： Deep oil and gas reservoir rock In situ temperature-preserved coring (ITP-Coring) Hollow glass microsphere/epoxy resin thermal insulation materials (HGM/EP materials) High-temperature and high-pressure (HTHP) Physical and mechanical properties

Chronic administration of triclosan leads to liver fibrosis through hepcidin-ferroportin axis-mediated iron overload

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Journal of Environmental Sciences 2024年第3期137卷 144-154页

作者： Jing Liu Lecong Zhang fang Xu ping Zhang Yang Song College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China The Institute of Karst Wetland Ecology Guizhou Minzu UniversityGuiyang 550025China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Triclosan(TCS)has been manufactured as an antibacterial compound for half a ***,it is widely used in various personal care products;however,its potential adverse effects raise a lot of ***,we create a long-term oral administration mouse model and identify the corresponding hepatotoxicity of *** discover that daily intragastric administration of 10 mg/kg TCS to mice for 12 weeks results in severe hepatic *** study displays that hepatic iron increased 18%,23%and 29%upon oral TCS treatment for4,8 and 12 weeks,*** by hepatic iron variation,splenic and duodenal iron are increased,which indicates systemic iron *** only excessive iron accumulated in the liver,abnormal hepatic malondialdehyde,prostaglandin synthase 2 and glutathione peroxidase 4 are pointed to *** study uncovers that hepcidin expression increases 7%,10%,4%in serum and 2.4-,4.8-,and 2.3-fold on transcriptional levels upon TCS exposure for 4,8 and 12 weeks,*** together,the mice in the TCS-treated group show disordered systemic iron homeostasis via the upregulated hepatic hepcidin-ferroportin ***,both hepatic iron overload(systemic level)and hepatocyte ferroptosis(cellular level)are accused of TCS-induced liver ***■,an iron scavenger,significantly ameliorates TCS-induced liver *** summary,this study confirms the impact of TCS on liver fibrosis;a critical signal pathway is also *** significance of the current study is to prompt us to reevaluate the“pros and cons”of TCS applications.

关键词： Triclosan Iron metabolism hepcidin hepatotoxicity Liver fibrosis