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Promotion effect of sulfur impurity in alumina support on propane dehydrogenation

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Journal of Energy Chemistry 2022年第7期31卷 332-339,I0009页

作者： xin-qian gao Wen-Cui Li Bin Qiu Jian Sheng Fan Wu An-Hui Lu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Alumina materials are widely applied either as a catalyst or support in various industrial catalytic processes. Impurities in alumina that are unfriendly to catalytic performance are inevitably present during the production processes. Facing this problem, we here report that the use of sulfur-containing alumina as the support can generate active alumina-supported platinum catalyst, which exhibits superior propylene selectivity and anti-coking ability during propane dehydrogenation. It demonstrated that the sulfur impurity in alumina is not entirely detrimental. During the reduction process, the formation of gas-phase sulfur species increased the electrons and poisoned unsaturated sites of platinum particles. The sulfur impurity in alumina can be removed through a hydrogen reduction process, and the degree of desulfurization is correlated with the operating temperature. This study demonstrated that the rational use of impurity will contribute to the design of a catalyst with high reactivity for potential applications.

关键词： Alumina Impurity Sulfur Platinum Propane dehydrogenation

The safety aspect of sodium ion batteries for practical applications

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Journal of Energy Chemistry 2024年第8期95卷 407-427,I0009页

作者： Yingshuai Wang Runqing Ou Jingjing Yang Yuhang xin Preetam Singh Feng Wu Yumin qian Hongcai gao School of Materials Science&Engineering Beijing Institute of TechnologyBeijing 100081China School of Physics Beijing Institute of TechnologyBeijing 100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019ZhejiangChina Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China Department of Ceramic Engineering Indian Institute of Technology(Banaras Hindu University)VaranasiUttar Pradesh 221005India

Sodium-ion batteries(SIBs)with advantages of abundant resource and low cost have emerged as promising candidates for the next-generation energy storage ***,safety issues existing in electrolytes,anodes,and cathodes bring about frequent accidents regarding battery fires and explosions and impede the development of high-performance ***,safety analysis and high-safety battery design have become prerequisites for the development of advanced energy storage *** reported reviews that only focus on a specific issue are difficult to provide overall guidance for building high-safety *** overcome the limitation,this review summarizes the recent research progress from the perspective of key components of SIBs for the first time and evaluates the characteristics of various improvement *** orderly analyzing the root causes of safety problems associated with different components in SIBs(including electrolytes,anodes,and cathodes),corresponding improvement strategies for each component were discussed *** addition,some noteworthy points and perspectives including the chain reaction between security issues and the selection of improvement strategies tailored to different needs have also been *** brief,this review is designed to deepen our understanding of the SIBs safety issues and provide guidance and assistance for designing high-safety SIBs.

关键词： Sodium ion batteries Safety Organic electrolytes modification Solid-state electrolyte Anode bulk modification Cathode bulk design

Novel Optimal Dispatch Method for Multiple Energy Sources in Regional Integrated Energy Systems Considering Wind Curtailment

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2166-2173页

作者： Yang gao qian Ai Key Laboratory of Control of Power Transmission and Conversion Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China

Power-to-gas technology uses temporary surplus electricity to create either renewable hydrogen or renewable natural gas,which can then be stored in natural-gas pipelines and used when *** a result,P2G transforms conventional one-way coupling of a power/heat/natural-gas system into twoway ***,its operating characteristics makes it possible to more effectively utilize *** paper describes a new optimal dispatch model for integrated electricity/gas/heat energy *** model considers the effective use of surplus wind-energy with electricity-to-gas ***,a multi-energy network model is built,taking into account both equipment and network ***,we apply a novel two-layer optimization method,which uses P2G,to“absorb”wind *** the top-layer model is used for the dayahead dispatch of the natural-gas network containing P2G,the bottom-layer model describes the day-ahead economic dispatch of the electricity/heat system,which includes wind *** on the Karush-Kuhn-Tucher conditions of the bottom-layer model,the two-layer model is transformed into a single-layer model,and we linearize the nonlinear equation to convert the nonlinear model into a mix-integer linear programming problem,which is solvable using the General Algebraic Modeling ***,numerical case-studies are performed to evaluate the accuracy and effectiveness of the proposed method.

关键词： Multi-enery coupling power-to-gas two-layer optimization wind-power consumption

Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： xin FENG Liaoliang KE Yang gao College of Science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are *** electro-elastic model is developed to investigate the anti-plane strain problem of Love wave *** introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated *** the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary *** examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect

Probabilistic seismic inversion based on physics-guided deep mixture density network

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Petroleum Science 2024年第3期21卷 1611-1631页

作者： qian-Hao Sun Zhao-Yun Zong xin Li National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Laoshan Laboratory Qingdao266580ShandongChina CNOOC Research Institute Ltd. Beijing100028China

Deterministic inversion based on deep learning has been widely utilized in model parameters *** by logging data,seismic data,wavelet and modeling operator,deterministic inversion based on deep learning can establish nonlinear relationships between seismic data and model ***,seismic data lacks low-frequency and contains noise,which increases the non-uniqueness of the *** conventional inversion method based on deep learning can only establish the deterministic relationship between seismic data and parameters,and cannot quantify the uncertainty of *** order to quickly quantify the uncertainty,a physics-guided deep mixture density network(PG-DMDN)is established by combining the mixture density network(MDN)with the deep neural network(DNN).Compared with Bayesian neural network(BNN)and network dropout,PG-DMDN has lower computing cost and shorter training time.A low-frequency model is introduced in the training process of the network to help the network learn the nonlinear relationship between narrowband seismic data and low-frequency *** addition,the block constraints are added to the PG-DMDN framework to improve the horizontal continuity of the inversion *** illustrate the benefits of proposed method,the PG-DMDN is compared with existing semi-supervised inversion *** synthetic data examples of Marmousi II model are utilized to quantify the influence of forward modeling part,low-frequency model,noise and the pseudo-wells number on inversion results,and prove the feasibility and stability of the proposed *** addition,the robustness and generality of the proposed method are verified by the field seismic data.

关键词： Deep learning Probabilistic inversion Physics-guided Deep mixture density network

Promotion effects of nickel-doped Al2O3-nanosheet-supported Au catalysts for CO oxidation

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Chinese Journal of Catalysis 2020年第2期41卷 350-356页

作者： Rao Lu Lei He Yang Wang xin-qian gao Wen-Cui Li State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Supported gold catalysts show high activity toward CO oxidation, and the nature of the support significantly affects the catalytic activity. Herein, serial Ni doping of thin porous Al2 O3 nanosheets was performed via a precipitation-hydrothermal method by varying the amount of Ni during the precipitation step. The prepared nanosheets were subsequently used as supports for the deposition of Au nanoparticles(NPs). The obtained Au/Nix Al catalysts were studied in the context of CO oxidation to determine the effect of Ni doping on the supports. Enhanced catalytic performances were obtained for the Au/Nix Al catalysts compared with those of the Au supported on bare Al2 O3. The Ni content and pretreatment atmosphere were both shown to influence the catalytic activity. Pretreatment under a reducing atmosphere was beneficial for improving catalytic activity. The highest activity was observed for the catalysts with a Ni/Al molar ratio of 0.05, achieving complete CO conversion at 20 °C with a gold loading of 1 wt%. The in-situ FTIR results showed that the introduction of Ni strengthened CO adsorption on the Au NPs. The H2-TPR and O2-TPD results indicated that the introduction of Ni produced new oxygen vacancies and allowed the oxygen molecules to be adsorbed and activated more easily. The improved catalytic performance after doping Ni was attributed to the smaller size of the Au NPs and more active oxygen species.

关键词： Alumina Gold catalyst Nickel doping CO oxidation Oxygen activation

Microstructure evolution and strengthening mechanism of high -performance powder metallurgy TA15 titanium alloy by hot rolling

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1426-1436页

作者： Ying gao Ce Zhang Jiazhen Zhang xin Lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsInstitute for Advanced Ma-terials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Engineering Research Center for Advanced Rolling Technology National Engineering Research Center for Flat Rolling EquipmentInstitute of Engin-eering TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying *** this study,Ti–6.5Al–2Zr–Mo–V(TA15)titanium alloy plates were prepared by cold press-ing sintering combined with high-temperature hot *** microstructure and mechanical properties under different process paramet-ers were *** microscope,electron backscatter diffraction,and others were applied to characterize the microstructure evolution and mechanical properties strengthening *** results showed that the chemical compositions were uniformly dif-fused without segregation during sintering,and the closing of the matrix craters was accelerated by increasing the sintering *** block was hot rolled at 1200℃ with an 80%reduction under only two passes without *** strength and elongation of the plate at 20–25℃ after solution and aging were 1247 MPa and 14.0%,respectively,which were increased by 24.5%and 40.0%,respect-ively,compared with the as-sintered alloy at 1300℃.The microstructure was significantly refined by continuous dynamic recrystalliza-tion,which was completed by the rotation and dislocation absorption of the substructure surrounded by low-angle grain *** hot rolling combined with heat treatment,the strength and plasticity of PM-TA15 were significantly improved,which resulted from the dense,uniform,and fine recrystallization structure and the synergistic effect of multiple slip systems.

关键词： elemental powder powder metallurgy titanium alloy hot rolling strength and plasticity

Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： Wei Li xin Pan Dehong Ge Jinji gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty *** accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite *** can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment *** composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed *** fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery *** experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation

Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： xin Xue Chao Zheng Fu-qiang Lai Xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this ***,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum ***,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried *** primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so *** results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner *** axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the ***,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping