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Investigation into the roles of interfacial H_(2)O structure in catalytic oxidation of HCHO and CO over CuMnO_(2) catalysts

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Journal of Environmental Sciences 2024年第3期137卷 310-320页

作者： Chunyan Ma Jushuang Pan Cheng Chen Yuanyuan Dong Feng Yao Fengbang wang Maoyong Song Key Laboratory of Environmental Nanotechnology and Health Effects Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China No.52 Institute of China North Industries Group Yantai Branch Co.Ltd. Yantai 264000China

The rapid deactivation of cost-effective MnO_(2)-based catalysts in humid air limits their application in practice,and the identification of the role of water in an oxidation process is significant for developing water-resistant MnO_(2)-based ***,CuMnO_(2)showed a20.3%HCHO conversion in 10 hr at room temperature in humid air with relative humidity of 40%,but deactivated in 3 hr in dry *** excellent activity and stability of HCHO oxidation in humid air were attributed to the positive effect of H_(2)O on HCHO oxidation to the H_(2)O-HOCH_(2)OH supermolecule assemblies via hydrogen bonds formed on CuMnO_(2).H_(2)O-HOCH_(2)OH supermolecule assemblies tend to be oxidized to carbonate,which is further oxidized to CO_(2).Furthermore,CuMnO_(2)exhibited a much poorer activity of CO oxidation in humid air,but the CO conversion was still 100%in 10 hr in dry air.H_(2)O showed a competitive adsorption effect to CO on CuMnO_(2).CuMnO_(2)could be applied in HCHO elimination in humid air and CO elimination in dry air.

关键词： H_(2)O-HOCH_(2)OH supermolecule HCHO oxidation Humid air CuMnO_(2) CO oxidation

Experimental and numerical investigations on micromixing performance of multi-orifice cross-flow jet mixers

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Chinese Journal of Chemical Engineering 2024年第6期70卷 63-72页

作者： Hang Yang Zhaojin Lu Likun Ma Wei Yin Bingjie wang Zhishan Bai Xiaoyong Yang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

Multi-orifice cross-flow jet mixers(MOCJMs)are used in various industrial applications due to their excellent mixing efficiency,but few studies have focused on the micromixing performance of ***,the flow characteristics and micromixing performance inside the MOCJM were investigated using experiments and computational fluid dynamics(CFD)simulations based on the Villermaux/Dushman system and the finite-rate/modified eddy-dissipation *** optimal A value was correlated with the characteristic parameters of MOCJMs to develop a CFD calculation method applicable to the study of the micromixing performance of the *** the micromixing efficiency was evaluated using the segregation index XS,and the effects of operational and geometric parameters such as mixing flow Reynolds number(ReM),flow ratio(RF),total jet area(ST),the number of jet orifices(n),and outlet configuration on the micromixing efficiency were *** was found that the intensive turbulent region generated by interactions between jets,as well as between jets and crossflows,facilitated rapid *** decreased with increasing ReM and decreasing ***,MOCJMs with lower ST,four jet orifices,and the narrower outlet configuration demonstrated a better micromixing *** study contributes to a deeper understanding of the micromixing performance of MOCJMs and provides valuable guidance for their design,optimization,and industrial application.

关键词： Multi-orifice cross-flow jet mixer Micromixing performance Finite-rate/modified eddy dissipation model Computational fluid dynamics Villermaux/Dushman reaction

Mechanism of a dual-phase Ti-Nb alloy exhibiting near-linear elastic deformation

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Rare Metals 2024年第5期43卷 2282-2289页

作者： Yan Guo wang Ding Wen Ma Shun Guo Hao-Dong Meng Nian-Yao Xu School of Automotive Engineering Changzhou Institute of TechnologyChangzhou 213032China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China Youke Publishing Co. LtdChina Grinm Group Co.LtdBeijing 100088China

In this work,the underlying mechanism responsible for the near-linear elastic deformation behavior of a dual-phase Ti-Nb alloy consisting of β and α'' phase with large recoverable strain was systematically *** on in situ synchrotron X-ray diffraction(SXRD)analyses,it was found that besides intrinsic elastic deformation,a slight reversible β-α'' stress-induced martensitic(SIM)transformation,which proceeded in a consecutive mode under the retarding effect of micro-defects,took place during the near-linear elastic *** unloading,a small amount of residual macroscopic strain remained in the specimen due to the incomplete reverse α''→β transformation on *** high near-linear elastic deformability of the cold drawing(CD)Ti-Nb alloy has been revealed to be attributed to the coupling actions of intrinsic elasticity as well as the consecutive and reversible β-α'' SIM *** research may contribute to a new avenue for the design and development of novel dual-phase Ti-based alloys with desirable elastic deformability.

关键词： Titanium alloys Dual-phase Near-linear elastic deformation Martensitictransformation

Gut microbiota intervention attenuates thermogenesis in broilers exposed to high temperature through modulation of the hypothalamic 5‑HT pathway

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Journal of Animal Science and Biotechnology 2024年第2期15卷 679-698页

作者： Sheng Li Xiaoqing Li Kai wang Yansen Li Kentaro Nagaoka Chunmei Li Research Centre for Livestock Environmental Control and Smart Production College of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095China Laboratory of Veterinary Physiology Department of Veterinary MedicineFaculty of AgricultureTokyo University of Agriculture and TechnologyTokyo 183‑8509Japan

Background Broilers have a robust metabolism and high body temperature,which make them less tolerant to hightemperature(HT)environments and more susceptible to challenges from elevated *** microbes,functioning as symbionts within the host,possess the capacity to significantly regulate the physiological functions and environmental adaptability of the *** study aims to investigate the effects of gut microbial intervention on the body temperature and thermogenesis of broilers at different ambient temperatures,as well as the underlying mechanism involving the"gut-brain"*** Broilers were subjected to gut microbiota interference with or without antibiotics(control or ABX)starting at 1 day of *** 21 day of age,they were divided into 4 groups and exposed to different environments for 7 d:The control and ABX groups at room temperature(RT,24±1℃,60%relative humidity(RH),24 h/d)and the control-HT and ABX-HT groups at high temperature(HT,32±1℃,60%RH,24 h/d).Results The results demonstrated that the antibiotic-induced gut microbiota intervention increased body weight and improved feed conversion in broiler chickens(P<0.05).Under HT conditions,the microbiota intervention reduced the rectal temperature of broiler chickens(P<0.05),inhibited the expression of avUCP and thermogenesisrelated genes in breast muscle and liver(P<0.05),and thus decreased thermogenesis ***,the gut microbiota intervention blunted the hypothalamic‒pituitary‒adrenal axis and hypothalamic–pituitary–thyroid axis activation induced by HT *** analyzing the cecal microbiota composition of control and ABX chickens maintained under HT conditions,we found that Alistipes was enriched in control *** contrast,antibioticinduced gut microbiota intervention resulted in a decrease in the relative abundance of Alistipes(P<0.05).Moreover,this difference was accompanied by increased hypothalamic 5-hydroxytryptamine(5-HT)content and TPH2 expression(P<0.05).Conclus

关键词： 5-HT Broiler chickens Gut microbiota Thermogenesis Thermoregulation

Stress corrosion cracking behavior of buried oil and gas pipeline steel under the coexistence of magnetic field and sulfate-reducing bacteria

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Petroleum Science 2024年第2期21卷 1320-1332页

作者： Jian-Yu He Fei Xie Dan wang Guang-Xin Liu Ming Wu Yue Qin College of Petroleum Engineering Liaoning Petrochemical UniversityFushun113001LiaoningChina Key Laboratory of Oil and Gas Storage and Transportation Technology in Liaoning Province Fushun113001LiaoningChina State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China PipeChina West East Gas Pipeline Company Shanghai200120China

Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.

关键词： Magnetic field Sulfate-reducing bacteria Film layer Stress corrosion cracking Oil and gas pipelines

A Multi-strategy Improved Snake Optimizer Assisted with Population Crowding Analysis for Engineering Design Problems

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Journal of Bionic Engineering 2024年第3期21卷 1567-1591页

作者： Lei Peng Zhuoming Yuan Guangming Dai Maocai wang Jian Li Zhiming Song Xiaoyu Chen School of Computer Science China University of GeosciencesWuhan430074China Hubei Key Laboratory of Intelligent Geo-Information Processing China University of GeosciencesWuhan430074China China Astronautics Standards Institute Beijing100071China

Snake Optimizer(SO)is a novel Meta-heuristic Algorithm(MA)inspired by the mating behaviour of snakes,which has achieved success in global numerical optimization problems and practical engineering ***,it also has certain drawbacks for the exploration stage and the egg hatch process,resulting in slow convergence speed and inferior solution *** address the above issues,a novel multi-strategy improved SO(MISO)with the assistance of population crowding analysis is proposed in this *** the algorithm,a novel multi-strategy operator is designed for the exploration stage,which not only focuses on using the information of better performing individuals to improve the quality of solution,but also focuses on maintaining population *** boost the efficiency of the egg hatch process,the multi-strategy egg hatch process is proposed to regenerate individuals according to the results of the population crowding *** addition,a local search method is employed to further enhance the convergence speed and the local search *** is first compared with three sets of algorithms in the CEC2020 benchmark functions,including SO with its two recently discussed variants,ten advanced MAs,and six powerful CEC competition *** performance of MISO is then verified on five practical engineering design *** experimental results show that MISO provides a promising performance for the above optimization cases in terms of convergence speed and solution quality.

关键词： Snake optimizer Multi-strategy Population crowding analysis Engineering design problem

Loyal wingman task execution for future aerial combat:A hierarchical prior-based reinforcement learning approach

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Chinese Journal of Aeronautics 2024年第5期37卷 462-481页

作者： Jiandong ZHANG Dinghan wang Qiming YANG Zhuoyong SHI Longmeng JI Guoqing SHI Yong WU School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

In modern Beyond-Visual-Range(BVR)aerial combat,unmanned loyal wingmen are pivotal,yet their autonomous capabilities are *** study introduces an advanced control algorithm based on hierarchical reinforcement learning to enhance these capabilities for critical missions like target search,positioning,and relay *** on a dual-layer model,the algorithm’s lower layer manages basic aircraft maneuvers for optimal flight,while the upper layer processes battlefield dynamics,issuing precise navigational *** approach enables accurate navigation and effective reconnaissance for lead ***,our Hierarchical Prior-augmented Proximal Policy Optimization(HPE-PPO)algorithm employs a prior-based training,prior-free execution method,accelerating target positioning training and ensuring robust target *** paper also improves missile relay guidance and promotes the effective *** integrating this system with a human-piloted lead aircraft,this paper proposes a potent solution for cooperative aerial *** experiments demonstrate enhanced survivability and efficiency of loyal wingmen,marking a significant contribution to Unmanned Aerial Vehicles(UAV)formation control *** advancement is poised to drive substantial interest and progress in the related technological fields.

关键词： Beyond-visual-range Loyal wingmen Hierarchical prior-augmented proximal policy optimization Unmanned aerial vehicles Warfare

A robust triaxial localization method of AE source using refraction path

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International Journal of Mining Science and Technology 2024年第4期34卷 521-530页

作者： Yichao Rui Jie Chen Jiongkun Chen Jiadong Qiu Zilong Zhou Wenzhong wang Jinyang Fan State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China School of Resources and Safety Engineering Central South UniversityChangsha 410083China Coal Geological Exploration Institute of Gansu Lanzhou 730030China

Acoustic emission(AE)localization algorithms based on homogeneous media or single-velocity are less accurate when applied to the triaxial localization *** the end,a robust triaxial localization method of AE source using refraction path is ***,the control equation of the refraction path is established according to the sensor coordinates and arrival ***,considering the influence of time-difference-of-arrival(TDOA)errors,the residual of the governing equation is calculated to estimate the equation ***,the refraction points in different directions are solved using Snell’s law and orthogonal ***,the source coordinates are iteratively solved by weighted correction *** feasibility and accuracy of the proposed method are verified by pencil-lead breaking *** simulation results show that the new method is almost unaffected by the refraction ratio,and always holds more stable and accurate positioning performance than the traditional method under different ratios and scales of TDOA outliers.

关键词： Acoustic emission(AE) Source localization Robust method Refraction paths Weight estimations

Evolution and Application of Sealing Ability of Gypsum Caprocks under Temperature-Pressure Coupling:An Example of the ZS5 Well in the Tazhong Area of the Tarim Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 168-184页

作者： LIU Hua ZHAO Shan YANG Xianzhang ZHU Yongfeng wang Shen ZHANG Ke National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong 266580China School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Laboratory for Marine Mineral Resources National Laboratory for Marine Science and TechnologyQingdaoShandong 266071China PetroChina Tarim Oil Field Company KorlaXinjiang 841001China

Gypsum caprocks'sealing ability is affected by temperature-pressure *** to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure *** stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility *** to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more *** reduces the amount of time it takes for the rock to transition from brittle to *** temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal *** sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are *** provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.

关键词： temperature-pressure coupling gypsum caprocks brittle-plastic evolution sealing capacity Tarim Basin