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A review on thermal application of metal foam

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Science China(Technological Sciences) 2020年第12期63卷 2469-2490页

作者： CHEN Kang GUO LieJin WANG Hui State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China Institute of Solar Engineering Technology Northwest Engineering Corporation LimitedPowerChinaXi’an 710065China School of Environmental Science and Engineering Donghua UniversityShanghai 201620China

Heat exchangers embedded with metal foam are drawing increasing attention in the thermal application field,due to the performance of low density,large ratio of surface area to volume as well as high thermal conductivity. In these applications,compact heat exchanger,solar thermal facilities and thermal energy storage are the three core components. This paper focuses on the lasted advances in thermal applications,presenting a review of theoretical and experimental progress over metal foam in thermal application. The empirical and theoretical models for pressure drop,heat transfer coefficient and performance evaluation criteria of compact heat exchangers with metal foam are reviewed and discussed,especially different optimized *** is a trade-off between heat transfer enhancement and increase of pressure drop. Some exploratory work performed by present authors are also introduced. The manufacturing,heat transfer and flow characteristics of tube bundle wrapped with metal foam are taken into account for optimization of heat exchanger. It is confirmed that the conversion mechanism of heat transfer is carried out that heat conduction is the dominative term at high dimension permeability. The correlations of heat transfer rate and pressure drop for staggered and single row tube bundle wrapped with metal foam are concluded,respectively. The effects of different bonding methods are revealed for point-contact in metal foam and base tube. The powder-sintering method can provide a stable and minimum-thickness bonding layer. Various types of solar thermal facilities utilized metal foam to improve the energy conversion efficiency from solar radiant energy to thermal energy are also reviewed and discussed,including solar collector for intermediate-low temperature utilization and solar receiver for high temperature utilization. The Last but not least,existing and future metal foam thermal application stations are overviewed.

关键词： metal foam heat transfer enhancement solar thermal facilities thermal energy storage

The Interaction and Activation of Fe2o3/Ceo2 Oxygen Carrier in Chemical Looping Dry Reforming of Methane

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SSRN 2024年

作者： Zhang, Jinrui Liu, Xiaozhi Pan, Yue Wang, Yuhan Yang, Tianlong Li, Peng Shen, Yuanhui Su, Dong Pan, Ying Jin, Hongguang Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University 710049 China

Chemical looping dry reforming of methane (CL-DRM) holds great promise for both CO2 utilization and syngas production with high efficiencies. The structure and component of oxygen carriers (OCs) are critical factors that influence the CL-DRM performances, such as reaction activity and production selectivity. Incorporating CeO2 is known to enhance the reactivity and stability of Fe2O3 for chemical looping reforming. However, the underlying mechanism of how CeO2 synergistically interact with Fe2O3 to enhance performances is still not clear. In this work, we comparatively investigate CeO2 supported Fe2O3 OCs in interfacial and physical Fe-Ce contact modes. The OC with sol-gel method achieves 80% CH4 conversion and 96% CO selectivity, significantly improved from OC with the mechanically mixed sample. Additionally, we found a strong interaction between Fe2O3 and CeO2 components, resulting in the formation of CeFeO3 after the first cycle. Our in-situ environmental transmission electron microscopy study shows that the Fe2O3-CeO2 interaction promotes the oxygen release during the reduction. Iron exhibited significant activity with ceria under CO2, dissolving into CeO2 lattice and forming CeFeO3. Density function theory results suggest that the improved reactivity of Fe2O3/CeO2 OC results from the enhanced oxygen ion migration in CeFeO3 © 2024, The Authors. All rights reserved.

关键词： Sol-gels

The Role of Particle-Vortex Interaction in Hydraulic Performance and Erosion Behavior of Semi-Open Centrifugal Pump: Effect of Particle Size

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SSRN 2023年

作者： Wang, Kai Liu, Hanyu Wang, Like Guo, Pengcheng Wang, Yueshe Yang, Junfeng State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of Technology No.5 Jinhua South Road Xi’an710048 China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University No.28 Xianning West Road Xi’an710049 China Shaanxi Provincial Dongzhuang Water Conservancy Engineering Co. Ltd Xi’an713200 China

The interaction between the particle migration and vortex evolution aggravates the complexity of erosion on the flow components. In this work, the liquid-solid two-phase flow of semi-open centrifugal pump under different particle sizes is simulated based on the four-way coupling Euler-Lagrange method, in which the fluid-particle interaction and particle-particle interaction are taken into account. The interrelationship among vortex structure, particle migration and surface erosion behavior is revealed. The results show that the erosion area is mainly distributed in the blade leading edge, the pressure surface inlet edge and the hub. When the particle size is 0.1 mm and 0.3 mm, due to the good following characteristic of particles and the inhibition effect on tip leakage vortex, the particles are easy to impact the outlet edge of blade suction surface and the hub, which induce severe erosion. As the particle size decreases, the number of particles flowing into the tip clearance layer increases. Therefore, the frequent impact of particles on the tip leakage vortex leads to the breakup, separation and refusion of the vortex, which aggravates the flow instability. This paper provides a new insight into the hydraulic performance and erosion characteristics of semi-open centrifugal pump in terms of particle-vortex interaction. © 2023, The Authors. All rights reserved.

关键词： Particle size

Degradation of Polystyrene to Aromatic Oils with Nio@C Catalyst in Supercritical Co2

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SSRN 2024年

作者： Liu, Yanbing Mao, Liuhao Kang, Xing Li, Yi Zhao, Qiuyang Jin, Hui Meng, Wei Shi, Jinwen Guo, Liejin International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University 28 West Xianning Road Shaanxi Xi’an710049 China Hunan Provincial Key Lab of Dark Tea and Jin-Hua Departmet of Material & Chemical Engineering Hunan City University 518 East Yingbin Road Hunan Yiyang413000 China

One of the most promising ways to dispose of plastic pollution in the future is chemical recycling of plastic, and in particular supercritical fluids with excellent fluidity and transferability have shown great attraction in the disposal of plastic. Herein, catalytic degradation of polystyrene (PS) plastic in supercritical carbon dioxide (Sc-CO2) was realized with high yield of aromatic oils. NiO with simple preparation process, and high catalytic activity and stability in Sc-CO2 was doped with carbon material to prepare NiO@C catalyst with improved catalytic performance. Compared with NiO, NiO@C catalyst had rich porous structure and strong acidic sites, resulting in higher catalytic activity. The NiO@C catalyzed degradation of PS in Sc-CO2 yielded aromatic oils as high as 89.3 ± 0.6 wt% at 300oC with a reaction time of 2 h and a catalyst loading amount of 10 wt%. Moreover, the NiO@C catalyst degraded PS in Sc-CO2 for three cycles without obvious change in the catalytic performance. Sc-CO2 not only played a favorable role in swelling PS, but also inhibited the formation of coke, beneficial for the degradation of PS. Furthermore, CO2 was be consumed as an oxidant to generate new products and reduce greenhouse gas emission. The highly efficient catalytic conversion of PS to aromatic oils in Sc-CO2 via NiO@C catalyst provides a potential route for simultaneously recycling plastic and sequestering carbon. © 2024, The Authors. All rights reserved.

关键词： Carbon dioxide

Development, Validation and Application of Sub-Channel Thermal-Hydraulic Analysis Code for Liquid Metal Cooled Reactor

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SSRN 2024年

作者： Wang, Jinshun Chen, Ronghua Liang, Yu Gui, Minyang Zhu, Xinyang Tian, Wenxi Qiu, Suizheng Su, Guanghui School of Nuclear Science and Technology Shaanxi Key Laboratory of Advanced Nuclear Energy and Technology State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an710049 China Nuclear Power Institute of China 328 Changshun Avenue Chengdu610213 China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu610213 China College of Nuclear Science and Technology Harbin Engineering University Harbin150001 China

The liquid metal reactor, specifically the lead-based fast reactor and the sodium-cooled fast reactor, are generally recognized as the most significant representatives of the Gen IV reactors due to their sustainability, economy, security and reliability. In order to conduct thermal-hydraulic safety analysis for liquid metal cooled fast reactors, adaptive improvements are made to the model and solution algorithms based on the sub-channel analysis method, and a Sub-channel Analysis Code Of Safety for Liquid Metal cooled Reactor (SACOS-LMR) is developed. The validation of SACOS-LMR is conducted using classic experimental data of liquid metal. The results show that the dimensionless temperature deviations of ORNL 19-pin test and Toshiba 37-pin test are within 10%, and the relative temperature deviations of KIT-KALLA 19-pin test are within 25%. These findings confirm the accuracy and reliability of SACOS-LMR in predicting the temperature distribution of liquid metal reactors. Ultimately, calculations conducted on the ALFRED lead-cooled fast reactor demonstrated the practical utility of the code and have certain guiding significance for its subsequent design and development. © 2024, The Authors. All rights reserved.

关键词： Liquid metals

Surface display of CadR protein on Rhodopseudomonas palustris CGA009 for enhanced heavy metal bioremediation

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Journal of Hazardous Materials 2025年 494卷 138592页

作者： Wang, Minmin Gao, Zixuan Jiang, Qiushi Mu, Xuefang Jiang, Youmin Li, Yanjing Zhang, Sihu Cao, Wen Guo, Liejin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xianning West Road Xi'an710049 China

Heavy metal pollution poses significant ecological and public health risks, and surface display engineering shows promise for bioremediation in this area. Although anoxygenic photosynthetic purple nonsulfur bacteria (PNSB) have been effectively applied to degrade pollutants due to their metabolic versatility, the use of surface display technology in PNSB remains very limited. In this study, we constructed a surface display system using Rhodopseudomonas palustris CGA009 as the host. The metal-binding protein CadR was fused with outer membrane protein A (OmpA) and expressed in CGA009. SDS-PAGE and immunofluorescence analysis identified the successful expression of the fusion protein on the cell surface. In addition, we used flow cytometry to explore the enhancement effects of linker peptides and different promoters on surface display efficiency under different light intensities. The surface display system enhanced the heavy metal resistance of the host bacteria, and the maximum removal rate of Cd2 + reached 95.6 %. By means of Langmuir isotherm analysis, the maximum biosorption capacity of the system for Cd2+ is 101.11 mg/g. The system demonstrates feasibility for application in complex real-world environmental samples. The presence of various metal ions does not interfere with the system's specific adsorption of Cd²⁺. It can stably maintain an adsorption efficiency of over 80 % under conditions of pH 6–8, temperatures of 20–35°C, and light intensity of 1000–6000 lux. Additionally, the system achieves a removal efficiency of 94.3 % in Cd wastewater. In summary, this study provides a reference for the development of photosynthetic bacterial surface display systems and provides an advanced bioremediation strategy for heavy metal contaminated wastewater. © 2025 Elsevier B.V.

关键词： Bioremediation

Experimental study on mercury content in flue gas of coal-fired units based on laser-induced breakdown spectroscopy

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Plasma Science and Technology 2020年第7期22卷 75-82页

作者： Kai RONG Zhenzhen WANG Ruomu HU Renwei LIU Yoshihiro DEGUCH Junjie YAN Jiping LIU State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049People’s Republic of China Graduate School of Technology Industrial and Social SciencesTokushima UniversityTokushima 770-8501Japan Moe Key Laboratory of Thermo-Fluid Science and Engineering Xi'an Jiaotong UniversityXi'an 710049People’s Republic of China

Accurate measurement of trace heavy metal mercury(Hg) in flue gas of coal-fired units is great significance for ecological and environmental *** gas was used to simulate the actual flue gas of a power plant in this study.A laser-induced breakdown spectroscopy(LIBS)system for Hg measurement in mixed gas was built to study the effect of mixed gas pressure,Hg concentration in mixed gas and delay time on Hg *** experimental results show that the appropriate low mixed gas pressure can obtain high Hg signal intensity and signal to noise *** Hg signal intensity and signal to noise ratio increased with the increase of Hg concentration in mixed *** Hg signal intensity and signal to noise ratio decreased with the increase in delay *** to the above results,the optimized measurement conditions can be *** Hg concentrations in mixed gas were quantitatively analyzed by the internal standard method and traditional calibration method *** relative error of prediction of the test sample obtained by the internal standard method was within 11.11%.The relative error of prediction of the traditional calibration method was less than 14.54%.This proved that the internal standard method can improve the accuracy of quantitative analysis of Hg concentration in flue gas using LIBS.

关键词： laser-induced breakdown spectroscopy flue gas trace heavy metal quantitative analysis

Experimental study on the contribution of included/excluded minerals to particulate formation during coal char combustion

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Fuel 2023年第1期346卷

作者： Shang, Yimin Liu, Siqi Niu, Yanqing Zhu, Guangqing Cheng, Zening Hui, Shi'en State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi'an Jiaotong University Shaanxi710049 China China Nuclear Power Technology Research Institute Shenzhen518031 China Zhundong Energy Research Institute Xinjiang Tianchi Energy Co. Ltd. Xinjiang831100 China

The contributions of included and excluded minerals to particulate matter formation are quantified in this work. By devolatilization of three typical Chinese coals, three coal chars with low (LA), moderate (MA), and high ash (HA) content (with both included and excluded minerals) were prepared, from which three float coal chars with low (LA−), moderate (MA−), and high ash (HA−) content (without excluded minerals) were separated by density differentiation method. The coal chars before and after separation were burned in a drop-tube furnace at 1600 K, the results of three float coal chars can directly reveal the contribution of included minerals, and the comparison of two kinds of chars with and without excluded minerals would reveal the excluded mineral contribution to ash distribution. The size distributions of the combustion-generated ash particle were obtained from the combination of ELPI+ and laser particle-size analyzer. The fractions of included/excluded minerals were obtained from SEM images. The results from the combustion of the float chars indicate the physical transformation of included minerals, while the results from original coal chars involve the transformation of both included and excluded minerals. Results indicate that the distribution of ash particles from included minerals for HA− char possesses a single peak, while the ash distributions of MA− and LA− char show a bi-modal shape. The excluded minerals in LA and MA chars mainly contribute to the ash emissions with sizes larger than 80 μm. The contribution from excluded minerals reach 86% to the ash particles of 205 μm for HA char, 54% for MA char and 51% for LA char. The number fractions of included minerals continuously decrease with a transformation into excluded minerals during char dynamic combustion. © 2023 Elsevier Ltd

关键词： Minerals

Recent advances in all-in-one flexible supercapacitors

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Science China Materials 2021年第1期64卷 27-45页

作者： Tiezhu Guo Di Zhou Wenfeng Liu Jinzhan Su Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an710049China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an710049China International Research Centre for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an710049China

The rise of personalized flexible electronics has promoted the rapid development of flexible supercapacitors due to their long service life,fast charging-discharging rates and safe *** from the traditional flexible supercapacitors,the all-in-one integrated flexible supercapacitors are more resistant to deformation and lower interface resistance,which have a broader application prospect in the field of flexible *** review briefly summarizes the preparation methods and electrochemical properties of some typical all-in-one supercapacitors,represented by planar and fibrous structures in recent ***,the basic understanding of traditional flexible supercapacitors and all-in-one integrated flexible supercapacitors,and the key parameters of the performance of flexible supercapacitors are ***,the hydrogel matrix all-in-one supercapacitors with different functional characteristics(stretchable,self-healing and compressible)and the nonhydrogel matrix(separator,flexible membrane)all-in-one supercapacitors are ***,the challenges and future development of flexible supercapacitors are considered.

关键词： flexible supercapacitors all-in-one hydrogel