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Molecular insights into oil detachment from hydrophobic quartz surfaces in clay-hosted nanopores during steam-surfactant co-injection

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Petroleum Science 2024年第4期21卷 2457-2468页

作者： Ben-Jie-Ming Liu Xuan-tong Lei Mohammadali Ahmadi Zhangxin Chen Department of Chemical and Petroleum Engineering University of Calgary Eastern Institute of Technology

Thermal recovery techniques for producing oil sands have substantial environmental impacts. Surfactants can efficiently improve thermal bitumen recovery and reduce the required amount of steam. Such a technique requires solid knowledge about the interaction mecha.ism between surfactants, bitumen,water, and rock at the nanoscale level. In particular, oil sands ores have extremely complex mineralogy as they contain many clay minerals(montmorillonite, illite, kaolinite). In this study, molecular dynamics simulation is carried out to elucidate the unclear mecha.isms of clay minerals contributing to the bitumen recovery under a steam-anionic surfactant co-injection process. We found that the clay content significantly influenced an oil detachment process from hydrophobic quartz surfaces. Results reveal that the presence of montmorillonite, illite, and the siloxane surface of kaolinite in nanopores can enhance the oil detachment process from the hydrophobic surfaces because surfactant molecules have a stronger tendency to interact with bitumen and quartz. Conversely, the gibbsite surfaces of kaolinite curb the oil detachment process. Through interaction energy analysis, the siloxane surfaces of kaolinite result in the most straightforward oil detachment process. In addition, we found that the clay type presented in nanopores affected the wettability of the quartz surfaces. The quartz surfaces associated with the gibbsite surfaces of kaolinite show the strongest hydrophilicity. By comparing previous experimental findings with the results of molecular dynamics(MD) simulations, we observed consistent wetting cha.acteristics. This alignment serves to validate the reliability of the simulation outcomes. The outcome of this paper makes up for the lack of knowledge of a surfactant-assisted bitumen recovery process and provides insights for further in-situ bitumen production engineering designs.

关键词： Clay minerals Bitumen Contact angle Interaction energy Surfactant Molecular dynamics

Coordinated Robust PID-based Damping Control of Permanent Magnet Synchronous generators for Low-frequency Oscillations Considering Power System Operational Uncertainties

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1042-1051页

作者： Rehan Sadiq Zhen Wang Chi Yung Chung Deqiang gan Cunzhi tong College of Electrical Engineering Zhejiang UniversityHangzhou 310058China The Hong Kong Polytechnic University Hong KongChina State grid Zhejiang Electric Power Company Hangzhou 310007China

In recent years, with the growth of wind energy resources,the capability of wind farms to damp low-frequency oscillations(LFOs) has provided a notable advantage for the stabilityenhancement of the modern power grid. Meanwhile, owingto variations in the power system operating point (OP), thedamping cha.acteristics of LFOs may be affected adversely. Inthis respect, this paper presents a coordinated robust proportional-integral-derivative (PID) based damping control approachfor permanent magnet synchronous generators (PMSgs)to effectively stabilize LFOs, while considering power system operationaluncertainties in the form of a polytopic model constructedby linearizing the power system under a given set ofOPs. The proposed approach works by modulating the DC-linkvoltage control loop of the grid-side converter (gSC) via a supplementaryPID controller, which is synthesized by transformingthe design problem into H-infinity static output feedback(SOF) control methodology. The solution of H-infinity SOF controlproblem involves satisfying linear matrix inequality (LMI)constraints based on the parameter-dependent Lyapunov functionto ensure asymptotic stability such that the minimal H-infinityperformance objective is simultaneously accomplished forthe entire polytope. The coordinated damping controllers forthe multiple wind farms are then designed sequentially by usingthe proposed approach. Eigenvalue analysis confirms the improveddamping cha.acteristics of the closed-loop system forseveral representative OPs. Afterward, the simulation results, includingthe performance comparison with existing approaches,validate the higher robustness of the proposed approach for awide range of operating scenarios.

关键词： Permanent magnet synchronous generator(PMSg) low-frequency oscillation(LFO) proportional-integralderivative(PID) robust control H-infinity static output feed-back control linear matrix inequality(LMI)

Topology optimization of modular structures with multiple assemblies and applications to airborne shelves

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Chinese Journal of Aeronautics 2024年第4期37卷 321-332页

作者： Jie WANg tong gAO Ming LI Jihong ZHU Longlong SONg Weihong ZHANg State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an 710072China Beijing Specialized Machinery Institute Beijing 100143China

This work is devoted to the aeronautical application of topology optimization for modular structures with multiple assemblies that consist of repeated standard modules and optional *** kinds of structures are widely used owing to their transportability,reconfigurability,low manufacturing and service *** this work,the design of airborne shelves with modular structures cha.acterized by the standard module configuration is formulated for the first time as a topology optimization problem of multiple assemblies and multiple load cases subjected to the volume *** is shown that the weighted compliance design of multiple assemblies is a compromising solution compared to the optimization result of each individual assembly of standard ***,the performance of optimized airborne shelves with the modular structures can effectively be ameliorated with the help of reinforcements.

关键词： Topology optimization Modular structures Multiple assemblies Standard modules Airborne shelves

Stacking order modulated anomalous valley Hall effect in antiferromagnetic MXene

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Journal of Materiomics 2024年第1期10卷 269-276页

作者： tong Zhao Shucheng Xing Jian Zhou Naihua Miao Zhimei Sun School of Materials Science and Engineering Beihang UniversityBeijing100191China Center for Integrated Computational Materials Engineering International Research Institute for Multidisciplinary ScienceBeihang UniversityBeijing100191China

The valley index is a promising degree of freedom for information processing in electronic ***,the researches on valley polarization are mainly focused on ferromagnetic order,which breaks the time reversal symmetry ***,a novel paradigm for achieving stacking order modulated anomalous valley Hall(AVH)effect is proposed in antiferromagnetic *** paradigm involves the introduction and reversal of nonuniform potentials by modulating the position of substrate,to break the combined symmetry of spatial inversion and time reversal(PT symmetry)and achieve stacking-dependent valley spin *** on first-principles calculations,we discover spontaneous valley polarization in antiferromagnetic Cr_(2)CH_(2) MXene and stacking-dependent valley spin splitting in Cr_(2)CH_(2)/Sc_(2)CO_(2) ***,switching the ferroelectric polarization of monolayer Sc_(2)CO_(2) results in a semiconductor-metal transition in Cr_(2)CH_(2)/Sc_(2)CO_(2),accompanied by the disappearance of valley *** findings provide an alternative way to develop controllable valleytronics devices based on antiferromagnetic monolayers.

关键词： Stacking order Antiferromagnetism AVH effect Electrical control

Effect of Fe Addition on Dehydrogenation Performance of Methylcyclohexance over Pt/Al_(2)O_(3)

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 12-18页

作者： tong Fengya Tian Hao Wang Hao Miao cha.gxi Song Lei Shanghai Research Institute of Petrochemical Technology SINOPEC Shanghai201208

Catalysts with varying Fe contents were prepared using a sequential impregnation method to investigate the effects of Fe addition on the physicochemical properties of Pt/Al_(2)O_(3) and their performance in methylcyclohexane(MCH)*** results demonstrated that the addition of Fe to Pt/Al_(2)O_(3) enhanced the electron density of Pt and improved catalytic activity,while exhibiting negligible influence on the catalytic selectivity for *** the Fe content was 0.057%,the catalyst exhibited the highest MCH consumption rate,which was approximately two times higher than that of the catalyst without ***,the incorporation of Fe inhibited the formation of coke and reduced the quantity of coke deposits on the catalyst,thereby improving its catalytic ***,Fe shows promise as a prospective secondary element for Pt/Al_(2)O_(3) to enhance the MCH dehydrogenation performance.

关键词： methylcyclohexane dehydrogenation hydrogen storage deactivation Fe addition

Effect of Three-High Rotary Piercing Process on Microstructure,Texture and Mecha.ical Properties of Magnesium Alloy Seamless Tube

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 953-968页

作者： Xiaofeng Ding Zehao Wu tong Li Jianxun Chen Yuanhua Shuang Baosheng Liu Heavy Machinery Engineering Research Center of Education Ministry Taiyuan University of Science and TechnologyTaiyuan030024China College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Mg alloy seamless tubes(MASTs)were prepared through three-high rotary piercing process,effect of billet temperature,feed angle and plug advance on microstructure,texture and mecha.ical properties of tubes were *** effect on the deformation mecha.ism and improving mecha.ical properties mecha.ism of this process for MASTs were *** results show that the grain size could be refined to 11.3-31.1%of the initial grain size and the microstructure was more uniform due to the accumulation of *** formation of high strain gradient at the grain boundary activated the non-basal *** piercing process could cha.ge the grain orientation of as-extruded billet and eliminate the initial basal texture to produce new favorable *** the process could accelerate the continuous dynamic recrystallization *** piercing,yield strength of pierced tubes decreased by 6.7%,ultimate tensile strength(UTS)and elongation increased by 32.4 and 45%,respectively,at optimal *** plate-shapedβ_(1)-Mg_(17)Al_(12) orientation transformed from basal plates to prismatic plates,facilitating the increase in UTS and *** decrease size of nanoscale precipitates could reduce the cracking *** critical resolved shear stress ratios of pyramidal(10−11)slip and(11−22)slip to basal slip for the sample including prismatic plates both decreased compared to that including basal *** could enhance the ductility of tube ***,grain boundary sliding could contribute to a better ductility via coordinating deformation and reducing stress concentration during piercing process.

关键词： Mg alloy tube Rotary piercing Microstructure Texture Mecha.ical properties

Study of poly-disperse aerosols deposition in turbulent flow with different Reynolds numbers

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Particuology 2024年第6期89卷 32-43页

作者： Zhicha. gao Yongzheng Chen Dandi Zhang Peng Chen Lili tong Xuewu Cao School of Mecha.ical Engineering Shanghai Jiao Tong UniversityShanghai200240China China Nuclear Power Technology Research Institute Co. Ltd.Shenzhen518000China

The turbulent deposition mecha.ism is one of the main mecha.isms of aerosol deposition in nuclear power plant *** experimental study of poly-disperse aerosol deposition in a horizontal tube is conducted,where the nominal Reynolds number(Re)is in a range of 3600–200,*** aerosol deposition velocity first increases and then decreases with the increase of Res,and at high Re,particle rebound occurs during aerosol deposition in the *** the Re is low,the aerosol deposition velocity increases with the increase of aerosol *** the Re is greater than 60,000,the deposition velocity first increases and then decreases with the increase of aerosol diameter due to particle surface rebound.A new aerosol deposition model has been developed by establishing the energy conservation equation of the rebounded particles in the viscous *** calculated results of the new model are in good agreement with these experimental results,and the error between the aerosol deposition velocity calculated by the model and experimental results is between−60%and 150%.

关键词： Aerosol Turbulent deposition Rebound High Reynolds number

Exercise-with-melatonin therapy improves sleep disorder and motor dysfunction in a rat model of ischemic stroke

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Neural Regeneration Research 2024年第6期19卷 1336-1343页

作者： Haitao Zhao tong Zhang Haojie Zhang Yunlei Wang Lingna Cheng School of Rehabilitation Medicine Capital Medical UniversityBeijingChina Department of Neurological Rehabilitation Beijing Bo’ai HospitalChina Rehabilitation Research CenterBeijingChina School of Rehabilitation Medicine University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina Laboratory of Brain Injury Repair and Rehabilitation China Rehabilitation Science InstituteBeijingChina

Exercise-with-melatonin therapy has complementary and synergistic effects on spinal cord injury and Alzheimer's disease,but its effect on stroke is still poorly *** this study,we established a rat model of ischemic stroke by occluding the middle cerebral artery for 60 *** treated the rats with exercise and melatonin therapy for 7 consecutive *** showed that exercise-with-melatonin therapy significantly prolonged sleep duration in the model rats,increased delta power values,and regularized delta power ***,exercise-with-melatonin therapy improved coordination,endurance,and grip strength,as well as learning and memory *** the same time,it led to higher hippocampal CA1 neuron activity and postsynaptic density thickness and lower expression of glutamate receptor 2 than did exercise or melatonin therapy *** findings suggest that exercise-withmelatonin therapy can alleviate sleep disorder and motor dysfunction by increasing glutamate receptor 2 protein expression and regulating hippocampal CA1 synaptic plasticity.

关键词： exercise glutamate receptor 2 hippocampus ischemic stroke learning melatonin memory sleep disorder synaptic plasticity

A finite-time fuzzy adaptive output-feedback fault-tolerant control for underactuated wheeled mobile robots systems

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Journal of Automation and Intelligence 2024年第2期3卷 111-118页

作者： Pingfan Liu Shaocheng tong The Electrical Engineering College Liaoning University of TechnologyJinzhouLiaoning121001China College of Science Liaoning University of TechnologyJinzhouLiaoning121001China

This paper investigates the adaptive fuzzy finite-time output-feedback fault-tolerant control (FTC) problemfor a class of nonlinear underactuated wheeled mobile robots (UWMRs) system with intermittent actuatorfaults. The UWMR system includes unknown nonlinear dynamics and immeasurable states. Fuzzy logic systems(FLSs) are utilized to work out immeasurable functions. Furthermore, with the support of the backsteppingcontrol technique and adaptive fuzzy state observer, a fuzzy adaptive finite-time output-feedback FTC scheme isdeveloped under the intermittent actuator faults. It is testifying the scheme can ensure the controlled nonlinearUWMRs is stable and the estimation errors are convergent. Finally, the comparison results and simulationvalidate the effectiveness of the proposed fuzzy adaptive finite-time FTC approach.

关键词： Underactuated wheeled mobile robots system Finite-time Fuzzy adaptive fault-tolerant control Output-feedback Intermittent actuator faults