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Journal of Thermal Science 2024年第5期33卷 1607-1617页

作者： DU Shen HE Yaling LI Dong LIU Zhanbin LI Mengjie National Innovation Platform(center)for Industry-education Integration of Energy Storage Technology Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of EducationXi’an Jiaotong UniversityXi’an710049China

Direct pore-scale and volume-averaging numerical simulations are two methods for investigating the performance of porous volumetric solar *** clarify the difference in the prediction of heat transfer processes,a direct comparison between these two methods was conducted at both steady state and transient *** numerical models were established based on X-ray computed tomography scans and a local thermal non-equilibrium model,*** empirical parameters,which are indispensable to the volume-averaging simulation,were determined by Monte Carlo ray tracing and direct pore-scale numerical *** predicted outlet air temperature of the receiver by the volume-averaging simulation method corresponded satisfactorily to that in the direct pore-scale *** largest discrepancies were observed when the receiver's working temperature was elevated,with differences of 5.5%and 3.68%for the steady state and transient state simulations,***,the volume-averaging method is incapable of capturing the local temperature information of the air and porous *** underestimates the inlet temperature of the receiver,leading to an overestimation of the receiver's thermal efficiency,with the largest difference being 6.51%.The comparison results show that the volume-averaging model is a good approximation to the pore-scale model when the empirical parameters are carefully selected.

关键词： porous media volumetric solar receiver pore-scale method volume-averaging method thermal performance

In situ atomic-scale tracking of unusual interface reaction circulation and phase reversibility in(de)potassiated alloy-typed anode

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Journal of Energy Chemistry 2024年第8期95卷 241-249,I0006页

作者： Lin Su Ruining Fu Shuangying Lei Yuchen Pan Chongyang Zhu Pengcheng Liu Feng Xu SEU-FEI Nano-Pico center Key Laboratory of MEMS of the Ministry of EducationSoutheast UniversityNanjing210096China

Alloy-typed anode materials,endowed innately with high theoretical specific capacity,hold great promise as an alternative to intercalation-typed counterparts for alkali-ion *** tremendous efforts devoted to addressing drastic volume change and severe pulverization issues of such anodes,the underlying mechanisms involving dynamic phase evolutions and reaction kinetics have not yet been fully ***,taking antimony(Sb)anode as a representative paradigm,its microscopic operating mechanisms down to the atomic scale during live(de)potassiation cycling are systematically unraveled using in situ transmission electron *** reversible phase transformations at single-particle level,that are Sb←→KSb_(2)←→KSb←→K_5Sb_(4)←→K_(3)Sb,were revealed during ***,multiple phase interfaces associated with different reaction kinetics coexisted and this phenomenon was properly elucidated in the context of density functional theory ***,previously unexplored unidirectional circulation of reaction interfaces within individual Sb particle is confirmed for both potassiation and *** on the empirical results,the surface diffusion-mediated potassiation-depotassiation pathways at single-particle level are *** work affords new insights into energy storage mechanisms of Sb anode and valuable guidance for targeted optimization of alloy-typed anodes(not limited to Sb)toward advanced potassium-ion batteries.

关键词： Alloy-typed anode Potassium storage mechanism In situ transmission electron microscopy Reaction interface

SnIP-type atomic-scale inorganic double-helix semiconductors: Synthesis, properties, and applications

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Nano Research 2024年第3期17卷 2111-2128页

作者： Mudussar Ali Bowen Zhang Muhammad Khurram Qingfeng Yan Engineering Research center of Advanced Rare Earth Materials(Ministry of education) Department of ChemistryTsinghua UniversityBeijing 100084China

Flexible inorganic double helical semiconductors similar to DNA have fueled the demand for efficient materials with innovative structures and excellent *** recent discovery of tin phosphide iodide(SnIP),the first carbon-free double helical semiconductor at an atomic level,has opened new avenues of research for semiconducting devices such as thermoelectric and sensor devices,solar cells,and *** has drawn significant academic attention due to its high structural flexibility,band gap in the visible spectrum range,and non-toxic ***,the recent progress in developing SnIP,including its prestigious structure,versatile and intriguing properties,and synthesis,is *** analogues of SnIP and SnIP-based hybrid materials and their applications in photocatalysis are also ***,the review concludes with a critical summary and future aspects of this new inorganic semiconductor.

关键词： tin phosphide iodide(SnIP) inorganic semiconductor inorganic double helix SnIP-based hybrids photocatalysis flexible material

Numerical investigation on the flow and thermal behaviors of the volumetric solar receivers with different morphologies

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Science China(Technological Sciences) 2024年第9期67卷 2749-2757页

作者： DU Shen LI Dong LI MengJie HE YaLing National Innovation Platform(center)for Industry-education Integration of Energy Storage Technology Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of EducationXi’an Jiaotong UniversityXi’an 710049China

Morphologies of the porous materials influence the processes of solar radiation transport, flow, and thermal behaviors within volumetric solar receivers. A comprehensive comparative study is conducted by applying pore scale numerical simulations on volumetric solar receivers featuring various morphologies, including Kelvin, Weaire-Phelan, and foam configurations. The idealized unit cell and X-ray computed tomography scan approaches are employed to reconstruct pore scale porous *** Carlo ray tracing and pore scale numerical simulations are implemented to elucidate the radiative, flow, and thermal behaviors of distinct receivers exposed to varying thermal boundary conditions and real irradiation situations. The findings demonstrate that the foam structure exhibits greater solar radiation absorptivity, while Kelvin and Weaire-Phelan structures enhance the penetration depth under non-perpendicular solar irradiation. In comparison with Kelvin and Weaire-Phelan configurations, the foam structure presents efficient convective heat transfer, with the Weaire-Phelan structure showing pronounced thermal non-equilibrium phenomena. The variance in convective heat transfer coefficient between Kelvin and Weaire-Phelan configurations is approximately 8.4%. The foam structure exhibits higher thermal efficiency and flow resistance under nonperpendicular irradiation compared to Kelvin and Weaire-Phelan structures, attributed to its smaller pore size and intricate flow channels. An increase of 1.3% in thermal efficiency is observed with a substantial rise in pressure drop of 32.2%.

关键词： volumetric solar receiver porous morphology pore scale method solar radiation absorption thermal performance flow resistance

Progress in processing of porous titanium:a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： Xiao-Li Yang Xian-Feng Du Zhi-Lin Xu Zhong-Shuai Liang Li-Long Xiong Engineering Research center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi'an Jiaotong UniversityXi'an 710049China

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace,marine engineering and biomedical fields due to their high corrosion resistance,low density,good biocompatibility and excellent mechanical ***,in this paper,a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes)for fabricating porous titanium is firstly covered in terms of their working principles,capabilities,shortcomings and ***,the influencing factors of various methods on final pore structure of porous Ti are ***,a summary of the chemical methods(CM)to obtain the porous Ti is also provided,such as dealloying method and reduction ***,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Observation of an upward lightning flash with 21 upward positive leaders initiated from different wind turbines in wind farm

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High Voltage 2024年第1期9卷 163-171页

作者： Li Cai Yifeng Ke Wenchao Fan Ruisheng Yan Mi Zhou Jianguo Wang Yadong Fan Engineering Research center of Ministry of education for Lightning Protection and Grounding Technology School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

As the wind turbine height increases,the probability of multiple upward leaders flashes within the wind farm *** this study,an upward lightning flash containing 21 upward positive leaders(UPLs)initiated from different wind turbines in Zhangbei Wind Farm was *** average speed of the UPLs was 1.2×10^(5) m/s,which mostly decreased to zero before reaching the cloud *** four UPLs developed to cloud height,with prolonged periods of bright light on three of them and with a minimum duration of 126 ms.A total of nine return strokes occurred on the other two dissipated leader channels,and the numbers of strokes on the two channels was six and three,*** average interstroke interval for the return strokes was 10.5 *** of these nine return strokes had peak currents smaller than 10 *** high-speed video frames confirmed that competition does exist between the UPLs,and the range of shielding effects increases as the height of the ULs *** effect of fan rotation on the initiation of upward leaders and the shielding effect between the wind turbines and upward leaders are discussed.

关键词： flash return initiated

Chatter suppression techniques in milling processes:A state of the art review

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Chinese Journal of Aeronautics 2024年第7期37卷 1-23页

作者： Zhenmin LI Qinghua SONG Peijian JIN Zhanqiang LIU Bing WANG Haifeng MA Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationSchool of Mechanical EngineeringShandong UniversityJinan 250061China National Demonstration center for Experimental Mechanical Engineering education Shandong UniversityJinan 250061China

Chatter in the machining system can result in a decrease in tool life,poor surface finish,conservative cutting parameters,*** many review papers promoting the understanding and research of this area,chatter suppression techniques are generally discussed within limited pages in the framework of comprehensive chatter-related *** recent years,the developments of smart materials,advanced sensing techniques,and more effective control strategies have led to some new progress in chatter ***,the widely used thin-walled parts present more and more severe machining challenges in their milling *** the above deficiencies,this paper summarizes the current state of the art in milling chatter *** classifications of chatter suppression techniques are proposed according to the working principle and control *** on the new classified framework,the mechanism and comparisons of different chatter suppression strategies are ***,the current challenges and potential tendencies of milling chatter suppression techniques are ***,integration,compactness,adaptability to workpiece geometry,and the collaboration of multiple control methods are predicted to be important trends in the future.

关键词： Active control Chatter suppression Damping Milling Regenerative effect

Emerging memristors and applications in reservoir computing

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Frontiers of physics 2024年第1期19卷 219-239页

作者： Hao Chen Xin-Gui Tang Zhihao Shen Wen-Tao Guo Qi-Jun Sun Zhenhua Tang Yan-Ping Jiang School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006China

Recently, with the emergence of ChatGPT, the field of artificial intelligence has garnered widespread attention from various sectors of society. Reservoir Computing (RC) is a neuromorphic computing algorithm used to analyze time-series data. Unlike traditional artificial neural networks that require the weight values of all nodes in the trained network, RC only needs to train the readout layer. This makes the training process faster and more efficient, and it has been used in various applications, including speech recognition, image classification, and control systems. Its flexibility and efficiency make it a popular choice for processing large amounts of complex data. A recent research trend is to develop physical RC, which utilizes the nonlinear dynamic and short-term memory properties of physical systems (photonic modules, spintronic devices, memristors, etc.) to construct a fixed random neural network structure for processing input data to reduce computing time and energy. In this paper, we introduced the recent development of memristors and demonstrated the remarkable data processing capability of RC systems based on memristors. Not only do they possess excellent data processing ability comparable to digital RC systems, but they also have lower energy consumption and greater robustness. Finally, we discussed the development prospects and challenges faced by memristors-based RC systems.

关键词： reservoir computing memristor resistive switching artificial synapse neuromorphic computing

Artificial synaptic simulating pain-perceptual nociceptor and brain-inspired computing based on Au/Bi_(3.2)La_(0.8)Ti_(3)O_(12)/ITO memristor

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Journal of Materiomics 2024年第6期10卷 1308-1316页

作者： Hao Chen Zhihao Shen Wen-Tao Guo Yan-Ping Jiang Wenhua Li Dan Zhang Zhenhua Tang Qi-Jun Sun Xin-Gui Tang School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou510006China

Recently, memristors have garnered widespread attention as neuromorphic devices that can simulate synaptic behavior, holding promise for future commercial applications in neuromorphic computing. In this paper, we present a memristor with an Au/Bi_(3.2)La_(0.8)Ti_(3)O_(12) (BLTO)/ITO structure, demonstrating a switching ratio of nearly 103 over a duration of 104 s. It successfully simulates a range of synaptic behaviors, including long-term potentiation and depression, paired-pulse facilitation, spike-timing-dependent plasticity, spike-rate-dependent plasticity etc. Interestingly, we also employ it to simulate pain threshold, sensitization, and desensitization behaviors of pain-perceptual nociceptor (PPN). Lastly, by introducing memristor differential pairs (1T1R-1T1R), we train a neural network, effectively simplifying the learning process, reducing training time, and achieving a handwriting digit recognition accuracy of up to 97.19 %. Overall, the proposed device holds immense potential in the field of neuromorphic computing, offering possibilities for the next generation of high-performance neuromorphic computing chips.

关键词： Artificial synapse Memristor Resistive switching Pain-perceptual nociceptor Neuromorphic computing

Nitrogen-doping boosts *CO utilization and H2O activation on copper for improving CO2 reduction to C2+ products

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Green Energy & Environment 2024年第9期9卷 1459-1465页

作者： Yisen Yang Zhonghao Tan Jianling Zhang Jie Yang Renjie Zhang Sha Wang Yi Song Zhuizhui Su Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Center for Carbon Neutral Chemistry Institute of Chemistry Chinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences Key Laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

To improve the electrocatalytic transformation of carbon dioxide （CO2） to multi-carbon (C2+) products is of great *** we developed a nitrogen-doped Cu catalyst,by which the maximum C2+Faradaic efficiency can reach 72.7%in flow-cell system,with the partial current density reaching 0.62 A *** in situ Raman spectra demonstrate that the *CO adsorption can be strengthened on such a N-doped Cu catalyst,thus promoting the*CO utilization in the subsequent C–C coupling ***,the water activation can be well enhanced by N doping on Cu *** to the synergistic effects,the selectivity and activity for C2+products over the N-deoped Cu catalyst are much improved.

关键词： Electrocatalytic CO 2 reduction reaction Copper catalyst Doping Multi-carbon products In situ Raman measurement