检索结果-内蒙古大学图书馆

A multi-physics model-based approach for macro-structured surface design to enhance heat transfer in R410A flash spray cooling systems

引用

International Journal of Heat and Mass Transfer 2025年 247卷

作者： Ye, Ying-Dong Lin, Xiang-Wei Zhou, Zhi-Fu Liu, Maochang Chen, Bin Lu, Youjun Jing, Dengwei State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China

Refrigerant flash spray cooling, which offers high heat flux dissipation at low temperatures, holds significant potential for thermal management of high-power electronic devices. While surface structure design can further amplify heat transfer performance, the lack of systematic methodologies to address the complexities of spray cooling has hindered progress. This study establishes a multi-physics computational framework that couples two-phase flash spray dynamics, liquid film heat transfer, and solid heat conduction to systematically optimize macro-structured surfaces. After validating the model against experimental data, the effects of surface geometry (flat, square, straight and pyramid fins) and dimensional parameters on cooling performance were analyzed. The pyramid structure demonstrated superior performance, achieving a 9 K reduction in surface temperature and a 70 % increase in effective heat transfer coefficient compared to the flat surface. Quantitative analysis revealed that optimal macro-structured design hinges on maximizing effective heat transfer area while ensuring uniform liquid film distribution via controlled droplet dynamics. Further parametric studies on nine pyramid geometries identified a base length of 1 mm and height-to-edge ratio of 0.7 as the optimal configuration, balancing heat transfer enhancement and manufacturing costs through a newly proposed Composite Heat Transfer Factor (CHTF). This work provides a mechanistic framework for designing enhanced surfaces in spray cooling systems, bridging critical gaps in both theoretical understanding and engineering application. © 2025 Elsevier Ltd

关键词： Film cooling

来源：评论

学校读者我要写书评

暂无评论

Boosting electrochemical reduction of CO_(2)to CO using molecule-regulated Ag nanoparticle in ionic liquids

引用

Green Energy & Environment 2025年第4期10卷 813-820页

作者： Fangfang Li Kuilin Peng Chongyang Jiang Shaojuan Zeng Xiangping Zhang Xiaoyan Ji Energy Engineering Division of Energy ScienceLuleåUniversity of TechnologyLuleå97187Sweden Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing100190China College of Chemical Engineering and Environment China University of PetroleumBeijing102249China

Electrochemical reduction of CO_(2)is a promising approach to convert CO_(2)to high-valued chemicals and ***,developing efficient electrocatalysts featuring desirable activity and selectivity is still a big *** this work,a strategy of introducing functionalized molecules with desirable CO_(2)affinity to regulate Ag catalyst for promoting electrochemical reduction of CO_(2)was ***,3-mercapto-1,2,4-triazole was introduced onto the Ag nanoparticle(Ag-m-Triz)for the first time to achieve selectively converting CO_(2)to carbon monoxide(CO).This Ag-m-Triz exhibits excellent performance for CO_(2)reduction with a high CO Faradaic efficiency(FECO)of 99.2%and CO partial current density of 85.0 mA cm^(-2)at-2.3 V ***/Agt in H-cell when combined with the ionic liquid-based electrolyte,30 wt%1-butyl-3-methylimidazolium hexafluorophosphate([Bmim][PF6])-65 wt%acetonitrile(AcN)-5 wt%H2O,which is 2.5-fold higher than the current density in Ag-powder under the same *** studies confirm that the significantly improved performance of Ag-m-Triz originates from(i)the stronger adsorption ability of CO_(2)molecule and(ii)the weaker binding energy to form the COOH*intermediate on the surface of Ag-m-Triz compared with the Ag-powder catalyst,which boosts the conversion of CO_(2)to *** research provides a facile way to regulate electrocatalysts for efficient CO_(2)reduction by introducing functionalized molecules.

关键词： CO_(2)reduction CO Electrochemical Molecule-regulated Silver Ionic liquid

来源：评论

学校读者我要写书评

暂无评论

Synthesis ofδ-MnO_(2)via ozonation routine for low temperature formaldehyde removal

引用

Journal of Environmental Sciences 2025年第1期147卷 642-651页

作者： Guijun Fan Yacong Guo Shaohua Chai Le Zhang Jian Guan Guojun Ma Ning Han Yunfa Chen State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China College of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Science and Technology on Particle Materials Institute of Process EngineeringChinese Academy of SciencesBeijing 361021China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Petrochemical Engineering&Environment Zhejiang Ocean UniversityZhoushan 316022China

Nowadays,it is still a challenge to prepared high efficiency and low cost formaldehyde(HCHO)removal catalysts in order to tackle the long-living indoor air ***,δ-MnO_(2)is successfully synthesized by a facile ozonation strategy,where Mn^(2+)is oxidized by ozone(O_(3))bubble in an alkaline *** presents one of the best catalytic properties with a low 100%conversion temperature of 85℃for 50 ppm of HCHO under a GHSV of 48,000 mL/(g·hr).As a comparison,more than 6 times far longer oxidation time is needed if O3 is replaced by O_(2).Characterizations show that ozonation process generates a different intermediate of tetragonalβ-HMnO_(2),which would favor the quick transformation into the final productδ-MnO_(2),as compared with the relatively more thermodynamically stable monoclinicγ-HMnO_(2)in the O_(2)***,HCHO is found to be decomposed into CO_(2)via formate,dioxymethylene and carbonate species as identified by room temperature insitu diffuse reflectance infrared fourier transform *** these results show great potency of this facile ozonation routine for the highly activeδ-MnO_(2)synthesis in order to remove the HCHO contamination.

关键词： δ-MnO_(2) Ozone oxidation HCHO oxidation In-situ DRIFTS

来源：评论

学校读者我要写书评

暂无评论

On the Oxidation Mechanism of n-Dodecane under Pure Oxygen Conditions from Low to High Temperatures

On the Oxidation Mechanism of n-Dodecane under Pure Oxygen C...

引用

AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Hong, Congjie Zou, Jiabiao Subburaj, Janardhanraj Farooq, Aamir Zhang, Yingjia Thuwal23955 Saudi Arabia State Key Laboratory of Multiphase Flows in Power Engineering Xi’an Jiaotong University Xi’an710049 China

ISBN: (纸本)9781624107238

This study investigates the combustion characteristics of n-dodecane under pure oxygen conditions, a critical scenario for rocket propulsion systems. Advanced laser absorption diagnostics were employed to measure the oxidation of key species, including n-dodecane, CO, and H2O, across a wide range of temperatures. The experimental data were used to refine chemical kinetic models by optimizing the rate coefficients of key reactions. The optimized models demonstrated improved predictive accuracy for ignition delay times and species concentration profiles, providing deeper insights into the combustion process. These findings enhance the understanding of n-dodecane combustion and contribute to the development of efficient and environmentally sustainable rocket propulsion technologies. Additionally, the study advances modeling methodologies, offering direct implications for the design of more robust and sustainable rocket engines. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Rockets

来源：评论

学校读者我要写书评

暂无评论

Kinetic study on the hydrogenation of dimethyl succinate to γ-butyrolactone

引用

RSC Advances 2025年第18期15卷 14307-14314页

作者： Du, Chengzhe Zhao, Chenghao Ma, Huixia Jiang, Rui Zhang, Huanling Zhou, Feng SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co. Ltd Dalian116100 China State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China

The hydrogenation of dimethyl succinate (DMS) to γ-butyrolactone (GBL) is crucial in producing high-value chemicals for pharmaceuticals, agrochemicals, and battery electrolytes. This study utilized a self-developed copper-based catalyst and a micro-fixed bed reactor to systematically investigate the effects of temperature, pressure, and the hydrogen-to-ester ratio on reaction performance. An intrinsic kinetic model was developed based on experimental data, with reaction rate constants and activation energies determined through standard regression techniques. The model correlated well with observed data, providing insights into reaction kinetics. Validation against experimental data indicated fair agreement across various conditions. Sensitivity analysis confirmed the model's robustness, making it useful for process optimization. This kinetic analysis offers insights to enhance the efficiency and cost-effectiveness of industrial GBL production, aiming to improve overall process yield and efficiency. © 2025 The Royal Society of Chemistry.

关键词： Rate constants

来源：评论

学校读者我要写书评

暂无评论

Numerical study of specific C-shaped heat exchanger using porous medium and coarse mesh coupling method

引用

International Journal of Thermal Sciences 2025年 210卷

作者： He, Shaopeng Wang, Shiqi Wang, Mingjun Tian, W.X. Qiu, S.Z. Su, G.H. State Key Laboratory of Multiphase Flow in Power Engineering School of Nuclear Science and Technology Xi'an Jiaotong University Xi'an710049 China

Porous medium method is an effective simplified approach for the heat exchanger simulation when the numerous tubes and complex structures bring unacceptable computational resources to full-scale simulation. However, for the specific C-shaped heat exchanger, the tube side resistance and flow distribution characteristics that significantly affects the heat transfer and natural circulation performance cannot be obtained by the traditional porous medium method coupled with the one-dimensional node model for tube side. It is urgent to develop a new coupling method that can not only simplify modeling and calculation, but also obtain tube side high-resolution flow heat transfer characteristics. This study presents a novel calculation method which couples the porous medium mesh and the tube side coarse mesh. The coupling method was then applied to a typical C-shaped passive residual heat removal heat exchanger (PRHR HX), which is significant to the stable operation and the mitigation of accident conditions in the nuclear power plant. The coupling calculation method was validated against the full-scaled simulation and data from scaled-down experiment. The average relative error of heat transfer power is 2.1 % under steady state conditions. Under transient conditions, the average absolute error of the fluid temperature and wall temperature are less than 6 K. Then the 3D thermal-hydraulic characteristics of PRHR HX was studied. Owing to a greater gravitational pressure head, the mass flow rates in the extended tubes surpass those in the shorter tubes by a relative deviation of 27.4 %. The upper horizontal tube's heat exchange capacity constitutes approximately 70 % of the total power, leading to enhanced natural circulation. The outlet temperatures from various tubes tend to equalize. The boiling area gradually extended down along the heat transfer tubes. Our work would present an innovative calculation method to the numerical study and design optimization of the C-shaped heat

关键词： Nuclear power plants

来源：评论

学校读者我要写书评

暂无评论

Thermal mechanical response analysis of the first wall in laser initial confinement fusion reactors

International Journal of Advanced Nuclear Reactor Design and...

引用

International Journal of Advanced Nuclear Reactor Design and Technology 2025年第2期7卷 147-155页

作者： Xinze Li Bingqian Zhang Chengcheng Tong Ronghua Chen Dalin Zhang Wenxi Tian Suizheng Qiu State Key Laboratory of Multiphase Flow in Power Engineering Shaanxi Key Laboratory of Advanced Nuclear Energy and Technology School of Nuclear Science and Technology Xi'an Jiaotong University Xi'an 710049 China

This paper investigates the thermo-mechanical response characteristics of the first wall of a laser initial confinement fusion reactor under periodic transient heat flux loads. The first wall of the reactor experiences extremely high instantaneous heat loads during the target compression process, leading to temperature and thermal stress oscillations, which can cause material fatigue damage. Finite element analysis is employed to model the first wall under various chamber sizes and target energies, and the thermal-mechanical response characteristics of W, W/Cu functional gradient materials, and blanket materials are studied under thermal shock and cyclic loading conditions. The results indicate that W/Cu functional gradient materials can effectively alleviate thermal stresses on the first wall, especially in addressing the stress concentration at the interface. Fatigue life of the first wall is assessed using the Basquin model, and it is found that increasing the chamber size and increasing the target frequency can significantly reduce temperature oscillations and thermal stresses, thus extending the service life of the first wall. This study provides valuable design references for the optimization and design of the first wall in laser initial confinement fusion reactor.

关键词： Laser inertial confinement fusion reactor First wall Heat oscillation Thermal fatigue

来源：评论

学校读者我要写书评

暂无评论

Promoting effect of d-band center and in-situ precipitation strategy on sulfur evolution reaction

引用

Journal of Energy Chemistry 2025年第5期104卷 740-748页

作者： Jun Pu Yun Tan Jiasen Yin Zihan Shen Shoujie Liu Kai Zhang Lei Zhou Yagang Yao Key Laboratory of Functional Molecular Solids Ministry of EducationAnhui Provincial Engineering Laboratory for New-Energy Vehicle Battery Energy-Storage MaterialsCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002AnhuiChina National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093JiangsuChina State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Anhui UniversityHefei 230601AnhuiChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Department of Electrical Engineering Eindhoven University of TechnologyEindhoven MB 5600the Netherlands

The slow conversion of polyphase in lithium-sulfur(Li-S)batteries not only intensifies the shuttle effect of lithium polysulfides(LiPSs),but also causes the continuous accumulation of inactive sulfur species,resulting in rapid capacity attenuation and sluggish dynamic ***,the promoting effect of atomic interface stress on sulfur reaction was investigated via CoFe-CoFe_(2)O_(4)heterogeneous nanosheets with a cavity *** strain force induced by the in-situ precipitation of Co Fe bimetallic alloy in oxide matrix increased the d-band center,which was conducive to the interaction between catalyst and Li *** sulfur cathode based on this two-dimensional(2D)nanosheet design showed an extremely high capacity of 751 mAh g^(-1)at 4 *** with a sulfur loading of 5.55 mg cm^(-2),its area capacity was still as high as 7.15 mAh cm^(-2).Meanwhile,the enhanced stability greatly improved the practical potential of Li-S batteries.

关键词： 2D nanosheets In-situ precipitation Strain effect D-band center Li-S batteries

来源：评论

学校读者我要写书评

暂无评论

Electrochemical evolution of a metal oxyhydroxide surface on two-dimensional layered metal phosphorus trisulfides enables the oxidation of amine to nitrile

引用

Carbon Energy 2025年第3期7卷 133-147页

作者： Binglan Wu Karim Harrath Marshet Getaye Sendeku Tofik Ahmed Shifa Yuxin Huang Jing Tai Fekadu Tsegaye Dajan Kassa Belay Ibrahim Xueying Zhan Zhenxing Wang Elisa Moretti Ying Yang Fengmei Wang Alberto Vomiero State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijingChina CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology(NCNST)BeijingChina Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of EducationCollege of Chemistry&Materials ScienceNorthwest UniversityXi'anChina State Key Laboratory of Multiphase Flow in Power Engineering International Research Center for Renewable EnergyXi'an Jiaotong UniversityShaanxiChina Fundamental Science Center of Rare Earths Ganjiang Innovation AcademyChinese Academy of ScienceGanzhouChina Ocean Hydrogen Energy R&D Center Research Institute of Tsinghua University in ShenzhenShenzhenChina Department of Molecular Sciences and Nanosystems Ca'Foscari University of VeniceVenezia MestreItaly Testing and Analysis Center Institute of Chemistry Chinese Academy of SciencesBeijingChina Department of Engineering Sciences and Mathematics Division of Materials ScienceLuleåUniversity of TechnologyLuleåSweden

Selective oxidation of amines to imines through electrocatalysis is an attractive and efficient way for the chemical industry to produce nitrile compounds,but it is limited by the difficulty of designing efficient catalysts and lack of understanding the mechanism of ***,we demonstrate a novel strategy by generation of oxyhydroxide layers on two-dimensional iron-doped layered nickel phosphorus trisulfides(Ni1-xFexPS_(3))during the oxidation of benzylamine(BA).In-depth structural and surface chemical characterizations during the electrocatalytic process combined with theoretical calculations reveal that Ni(1-x)FexPS_(3) undergoes surface reconstruction under alkaline conditions to form the metal oxyhydroxide/phosphorus trichalcogenide(NiFeOOH/Ni1-xFexPS_(3))***,the generated heterointerface facilitates BA oxidation with a low onset potential of 1.39 V and Faradaic efficiency of 53%for benzonitrile(BN)*** calculations further indicate that the as-formed NiFeOOH/Ni1-xFexPS_(3) heterostructure could offer optimum free energy for BA adsorption and BN desorption,resulting in promising BN synthesis.

关键词： 2D layered materials benzylamine oxidation metal phosphorus trichalcogenides surfacereconstructed heterostructure

来源：评论

学校读者我要写书评

暂无评论

Graph neural network-driven prediction of high-performance CO_(2)reduction catalysts based on Cu-based high-entropy alloys

引用

Chinese Journal of Catalysis 2025年第4期71卷 197-207页

作者： Zihao Jiao Chengyi Zhang Ya Liu Liejin Guo Ziyun Wang International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityShaanxi 710049China School of Chemical Sciences University of AucklandAuckland 1010New Zealand

High-entropy alloy(HEA)offer tunable composition and surface structures,enabling the creation of novel active sites that enhance catalytic performance in renewable energy ***,the inherent surface complexity and tendency for elemental segregation,which results in discrepancies between bulk and surface compositions,pose challenges for direct investigation via density functional *** address this,Monte Carlo simulations combined with molecular dynamics were employed to model surface segregation across a broad range of elements,including Cu,Ag,Au,Pt,Pd,and *** analysis revealed a trend in surface segregation propensity following the order Ag>Au>Al>Cu>Pd>*** capture the correlation between surface site characteristics and the free energy of multi-dentate CO_(2)reduction intermediates,a graph neural network was designed,where adsorbates were transformed into pseudo-atoms at their centers of *** model achieved mean absolute errors of 0.08–0.15 eV for the free energies of C_(2)intermediates,enabling precise site activity *** indicated that increasing the concentration of Cu,Ag,and Al significantly boosts activity for CO and C_(2)formation,whereas Au,Pd,and Pt exhibit negative *** screening stable composition space,promising HEA bulk compositions for CO,HCOOH,and C_(2)products were predicted,offering superior catalytic activity compared to pure Cu catalysts.

关键词： Density functional theory Machine learning CO_(2)reduction High entropy alloys Graph neural network

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：