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Science China Chemistry 2024年第11期67卷 3886-3896页

作者： yun-dong cao Yuxi Zhang Jian Song Hong Liu Zhiyuan Song Lin-Lin Fan Cai-Li Lv Guang-Gang Gao School of Materials Science and Engineering University of Jinan

The major impediment to the additional industrialization of water splitting is the high cost of the co-catalyst made of noble metals and the sacrificial reagent. A binary photocatalytic system, consisting of B-doped g-C3N4nanosheets(Cu20@BCN-X) and atomically accurate copper clusters, is designed in this study. The copper clusters serve as co-catalysts for H2evolution and exhibit Pt-like activity, whereas the nanosheets serve as carriers and semiconductor components for O2evolution. Such binary system, created using simple techniques, demonstrates hydrogen bonding interactions that promote synergistic effects and efficient binding and charge transfer across the interface between the two components. Band position manipulation of carbon nitride nanosheets demonstrates a Z-scheme charge transfer mechanism between the nanosheets and copper clusters. This photocatalytic system can accomplish the photocatalytic overall water splitting process(259.9 μmol g-1h-1of H2and 129.4 μmol g-1h-1of O2) without using sacrificial agents or noble metal co-catalysts. This work lays the foundation for the design of overall water splitting catalysts by precisely manipulating the energy levels, and it also paves the way for commercialized photocatalytic catalysts that do not require noble metals or sacrificial chemicals.

关键词： copper clusters band modulation photocatalysts water splitting

Fluid-chemical modeling of the near-cathode sheath formation process in a high current broken in DC air circuit breaker

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Chinese Physics B 2024年第1期33卷 523-538页

作者：彭世东李静段薇曹云东刘树鑫黄浩 Key Laboratory of Special Electric Machine and High Voltage Apparatus Shenyang University of TechnologyShenyang 110870China

When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop through the near-electrode sheath is an important means to build up the arc voltage, which directly determines the current-limiting performance of the DCCB. A numerical model to describe the near-electrode sheath formation process can provide insight into the physical mechanism of the arc formation, and thus provide a method for arc energy regulation. In this work, we establish a two-dimensional axisymmetric time-varying model of a medium-voltage DCCB arc when interrupted by high current based on a fluid-chemical model involving 16 kinds of species and 46 collision reactions. The transient distributions of electron number density, positive and negative ion number density, net space charge density, axial electric field, axial potential between electrodes, and near-cathode sheath are obtained from the numerical model. The computational results show that the electron density in the arc column increases, then decreases, and then stabilizes during the near-cathode sheath formation process, and the arc column's diameter gradually becomes wider. The 11.14 V–12.33 V drops along the17 μm space charge layer away from the cathode(65.5 k V/m–72.5 k V/m) when the current varies from 20 k A–80 k *** homogeneous external magnetic field has little effect on the distribution of particles in the near-cathode sheath core,but the electron number density at the near-cathode sheath periphery can increase as the magnetic field increases and the homogeneous external magnetic field will lead to arc diffusion. The validity of the numerical model can be proven by comparison with the experiment.

关键词： near-cathode sheath atmospheric pressure air arc fluid-chemical model high current DC air circuit breaker(DCCB)

Improved Corrosion Resistance of Selective Laser Melted Ti–5Cu Alloy Using Atomized Ti–5Cu Powder

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Acta Metallurgica Sinica(English Letters) 2019年第8期32卷 1007-1014页

作者： Ying Han Hong-Rui Wang yun-dong cao Wen-Tao Hou Shu-Jun Li School of Electrical Engineering Shenyang University of TechnologyShenyang 110870China Titanium Alloy Laboratory Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The different types of metal powder used for selective laser melting(SLM) process would cause distinct corrosion behavior due to the uniformity of the obtained *** SLM-produced Ti–5Cu alloy using atomized Ti–5Cu metal powder(SLMed Ti–5Cu) in this work reveals a relatively uniform microstructure with overwhelming acicular α/α′ phase and shows great advantages on corrosion resistance compared with the SLM-produced Ti–5Cu alloy using the mixture powder(SLMedM Ti–5Cu).The effect of the micro-galvanic cells decreases due to the undetectable Ti2Cu phase in the microstructure of the SLMed Ti–*** apparent passivation behavior was observed for SLMed Ti–5Cu instead of severe pitting phenomenon for the SLMed-M Ti–*** charge transfer resistance of SLMed Ti–5Cu in this work is 10.09 ± 2.63 MΩ cm2, which is significantly higher than that of SLMed-M Ti–5Cu(4.76 MΩ cm2).The above result indicates the atomized Ti–5Cu powder plays an important role in the formation of the uniform microstructure of SLMed product, thereby enhancing its corrosion resistance in Hank’s solution at 37 ℃.

关键词： Selective laser melting Corrosion behavior Uniform microstructure Ti-5Cu Passivation Polarization resistance

The practically renewable and highly efficient electrocatalysts derived from a newly-designed Mo_(8)Pt polyoxometalate compound

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Science China Chemistry 2023年第2期66卷 492-499页

作者： Di Yin yun-dong cao Yi Feng Guang-Gang Gao Hong Liu Lin-Lin Fan Zhen-Hui Kang School of Materials Science and Engineering University of JinanJinan250022China Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-based Functional Materials and DevicesSoochow UniversitySuzhou215123China Macao Institute of Materials Science and Engineering(MIMSE) MUST-SUDA Joint Research Center for Advanced Functional MaterialsMacao University of Science and TechnologyTaipaMacao999078China

Platinum(Pt)catalysts are the most practical electrocatalysts;however,their low abundance and high cost severely limit their large-scale *** recovery is a key issue to be resolved before the use of Pt-based electrocatalysts can be broadly ***,the newly designed polyoxometalate[Pt^(II)(NH_(3))_(4)]_(2)[Mo_(8)O26](Mo_(8)Pt)acts as an ideal recycling medium for renewable and highly effective Pt *** from Mo_(8)Pt,by a facile reduction reaction,the formed Pt/Mo_(2)C/Mo_(2)N@C-N electrocatalyst shows superior electrocatalytic activity as compared to commercial Pt/C(20%)under both acidic and alkaline ***,the reaction of Pt/Mo_(2)C/Mo_(2)N@C-N in H_(2)O_(2)solution can regenerate Mo_(8)Pt for Pt *** is also demonstrated that the Pt electrocatalyst can be used for at least five rounds of recycling and regeneration,showing its efficiency and stability as well as its *** work highlights a recycling medium strategy to the new generation of renewable Pt-based catalysts.

关键词： platinum polyoxometalate electrocatalyst recycling-medium renewability

Deep decalcification of factory-provided freezing acidolysis solution to achieveα-high-strength gypsum

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Chinese Journal of Chemical Engineering 2024年第5期69卷 143-151页

作者： Wencai Ye Yulu Li Yonggang dong Lin Yang yun Yi Jianxin cao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China Engineering Research Center of Efficient Utilization for Industrial Waste Guizhou UniversityGuiyang 550025China Key Laboratory of Guizhou Province for Green Chemical Industry and Clean Energy Technology Guizhou UniversityGuiyang 550025China

The freezing acidolysis solution of the nitric acid-phosphate fertilizer process has a high calcium content,which makes it difficult to produce fine phosphate and high water-soluble phosphate fertilizer ***,based on the potential crystallization principle of calcium sulfate in NH_(4)NO_(3)-H_(3)PO_(4)-H_(2)O,the deep decalcification(*** removal)technology to achieveα-high-strength gypsum originated from freezing acidolysis-solutions has been firstly proposed and ***,calcium can be removed from the factory-provided freezing acidolysis-solution by neutralizing it with ammonia,followed by the addition of ammonium sulfate *** a result,the formation of calcium sulfate in the reaction system undergoes the nucleation and growth of CaSO_(4)·2H_(2)O(DH),as well as its dissolution and crystallization into short columnarα-CaSO_(4)·0.5H_(2)O(α-HH).Remarkably,with the molar ratio of SO_(4)^(2-)/Ca^(2+)at 1.8,the degree of neutralization(NH_(3)/HNO_(3) molar ratio)at 1.7,the reaction temperature of 94℃,and the reaction time of 300 min,the decalcification rate can reach 86.89%,of which the high-strengthα-CaSO_(4)·0.5H_(2)O(α-HH)will be ***,the deep decalcification product meets the standards for the production of fine phosphates and highly water-soluble phosphate ***,the 2 h flexural strength ofα-HH is 5.3 MPa and the dry compressive strength is 36.8 MPa,which is up to the standard of commercialα-HH.

关键词： Nitrophosphate Ammonia neutralization Deep decalcification High-strengthα-hemihydrate gypsum Controlled crystallization at atmospheric pressure

Plasma spray coating on interconnector toward promoted solid oxide fuel cells and solid oxide electrolysis cells

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Frontiers in Energy 2024年第3期18卷 390-398页

作者： Junwen cao yun ZHENG Wenqiang ZHANG Bo YU Institute of Nuclear and New Energy Technology(INET) Collaborative Innovation Center of Advanced Nuclear Energy TechnologyTsinghua UniversityBeijing 100084China Department of Chemical Engineering University of WaterlooWaterlooOntario N2L 3G1Canada Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

Interconnector is a critical component to construct solid oxide cells (SOCs) stack. Oxidation of metallic interconnectors and Cr poisoning caused by oxidation are important factors that lead to long-term performance degradation of SOCs. Coating on the interconnector surface is an important approach to inhibit the oxidation and Cr migration of the interconnector. Herein, (La0.75Sr0.25)0.95MnO3–δ (LSM) and Mn1.5Co1.5O4 (MCO) are used to fabricate the coatings of interconnector. Two advanced thermal spray technology, atmospheric plasma spraying (APS) and low-pressure plasma spray (LPPS), are adopted for the coating preparation. The electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition performance of the coatings are tested and evaluated. The result indicates that MCO can generate more uniform and denser coatings than LSM. In addition, MCO coatings prepared by LPPS shows the best electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition. The initial area specific resistance (ASR) is 0.0027 Ω·cm2 at 800 °C. After 4 cooling cycle tests, the ASR increases to 0.0032 Ω·cm2 but lower than other samples. Meanwhile, the relative intense of Cr at the interface of SUS430 with MCO coatings fabricated by LPPS is lower than that of MCO fabricated by APS after 4 rising and cooling cycle operations, showing more favorable Cr diffusion inhibition performance.

关键词： interconnector coating plasma spray electrochemical performance Cr diffusion inhibition solid oxide cells(SOCs)

Adaptive 5G-and-beyond network-enabled interpretable federated learning enhanced by neuroevolution

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Science China(Information Sciences) 2024年第7期67卷 107-132页

作者： Bin cao Jianwei ZHAO Xin LIU yun LI State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology School of Artificial Intelligence Hebei University of Technology School of Economics and Management Hebei University of Technology Industrial Artificial Intelligence Centre Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of China

Mobile telemedicine systems based on the next-generation communication will significantly enhance deep fusion of network automation and federated learning(FL), but data privacy is a paramount issue in sectors like healthcare. This work hence considers FL augments 5G-and-beyond networks by training deep learning(DL) models without the need to exchange raw data. The substantial communication loads imposed on by extensive parameters involved in DL models are managed through adaptive scheduling mechanisms effectively. To address the opaque nature of DL models and to improve the interpretability of FL models, we introduce a convolutional fuzzy rough neural network specifically designed for medical image processing. We also develop a multiobjective memetic evolutionary algorithm to streamline and optimize the neural network architectures. Our comprehensive FL framework integrates smart scheduling, interpretable fuzzy rough logic,and neuroevolution. This framework is shown to improve communication efficiency, increase interpretability of diagnosis with protected privacy, and generate low-complexity neural architectures.

关键词： 5G-and-beyond network interpretable federated learning mobile telemedicine system fuzzy rough set theory neuroevolution

A Novel CCA-NMF Whitening Method for Practical Machine Learning Based Underwater Direction of Arrival Estimation

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Journal of Beijing Institute of Technology 2024年第2期33卷 163-174页

作者： yun Wu Xinting Li Zhimin cao School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China

Underwater direction of arrival(DOA)estimation has always been a very challenging theoretical and practical *** to the serious non-stationary,non-linear,and non-Gaussian characteristics,machine learning based DOA estimation methods trained on simulated Gaussian noised array data cannot be directly applied to actual underwater DOA estimation *** order to deal with this problem,environmental data with no target echoes can be employed to analyze the non-Gaussian ***,the obtained information about non-Gaussian components can be used to whiten the array *** on these considerations,a novel practical sonar array whitening method was ***,based on a weak assumption that the non-Gaussian components in adjacent patches with and without target echoes are almost the same,canonical cor-relation analysis(CCA)and non-negative matrix factorization(NMF)techniques are employed for whitening the array *** the whitened array data,machine learning based DOA estimation models trained on simulated Gaussian noised datasets can be used to perform underwater DOA estimation *** results illustrated that,using actual underwater datasets for testing with known machine learning based DOA estimation models,accurate and robust DOA estimation performance can be achieved by using the proposed whitening method in different underwater con-ditions.

关键词： direction of arrival(DOA) sonar array data underwater disturbance machine learn-ing canonical correlation analysis(CCA) non-negative matrix factorization(NMF)

Targeting synaptic pathology in Alzheimer’s disease

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Zoological Research 2024年第4期45卷 875-876页

作者： Jing cao yun-Wu Zhang Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceSchool of MedicineXiamen UniversityXiamenFujian 361102China

Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by memory and cognitive *** two primary pathological hallmarks of AD include the accumulation ofβ-amyloid(Aβ)plaques and formation of neurofibrillary tangles(NFTs)composed predominantly of hyperphosphorylated tau protein(Zhang et al.,2023).Moreover,synaptic dysfunction is considered another crucial factor in AD pathogenesis and is closely associated with cognitive ***,synaptic damage,loss,and dysfunction manifest earlier than the pathological features of Aβplaques and NFTs(Knopman et al.,2021).Therefore,understanding the mechanisms underlying synaptic dysfunction in AD is vital for providing insights into disease mechanisms and developing novel therapeutic strategies.

关键词： Alzheimer Aβ tau

Monomeric and self-assembled crystal phases of TNBT

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Rare Metals 2024年第10期43卷 5442-5448页

作者： yun-Hui Wu Hua-Bei You Wei-Kai Cui Zhi-Qian cao Xiao dong Zi-Hui Meng Ming Huang School of Chemistry and Chemical Engineering Beijing Institute of Technology Institute of Chemical Materials China Academy of Engineering Physics

（3,3′,5,5′-Tetranitro-4,4′-bi-1,2,4-Triazole） TNBT was designed and predicted more than three decades ago as a high energy *** with many other designed molecules,TNBT has not been successfully synthesized and has not been computationally studied in *** this work,theoretical calculations at density functional theory （DFT）level of theory were carried out for both the gas phase molecule and its possible bulk crystal *** （DFT） computations show that TNBT is comparable to CL-20 with high bulk density,

关键词： Density functional theory