Corrosion poses a major threat to the safety of transportation ***,it is crucial to have an in-depth understanding of corrosion mechanisms in pipeline steels for the effective management of pipeline *** research on co...
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Corrosion poses a major threat to the safety of transportation ***,it is crucial to have an in-depth understanding of corrosion mechanisms in pipeline steels for the effective management of pipeline *** research on corrosion mechanisms relies on the use of efficient and reliable corrosion monitoring and analysis *** advancements in corrosion monitoring techniques specifically designed for the localized corrosion monitoring were aimed to be introduced,and a comprehensive overview of recent progress in understanding the localized corrosion mechanisms in pipeline steels was *** on the different corrosive environments encountered,the localized corrosion issues inside pipelines are classified into two categories:localized corrosion primarily influenced by electrochemical processes and localized corrosion controlled by both electrochemical and mechanical ***,a thorough analysis of the synergistic effects between micro-cell and macro-cell currents,as well as the interplay of mechanics and electrochemistry is ***,recommendations for future research on the mechanisms of internal localized corrosion in pipelines are provided.
Lithium metal is one of the most promising anodes for lithium batteries because of their high theoretical specific capacity and the low electrochemical potential. However, the commercialization of lithium metal anodes...
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Lithium metal is one of the most promising anodes for lithium batteries because of their high theoretical specific capacity and the low electrochemical potential. However, the commercialization of lithium metal anodes(LMAs) is facing significant obstacles, such as uncontrolled lithium dendrite growth and unstable solid electrolyte interface, leading to inferior Coulombic efficiency, unsatisfactory cycling stability and even serious safety issues. Introducing low-cost natural clay-based materials(NCBMs) in LMAs is deemed as one of the most effective methods to solve aforementioned issues. These NCBMs have received considerable attention for stabilizing LMAs due to their unique structure, large specific surface areas, abundant surface groups, high mechanical strength, excellent thermal stability, and environmental friendliness. Considering the rapidly growing research enthusiasm for this topic in the last several years, here, we review the recent progress on the application of NCBMs in stable and dendrite-free *** different structures and modification methods of natural clays are first summarized. In addition, the relationship between their modification methods and nano/microstructures, as well as their impact on the electrochemical properties of LMAs are systematically discussed. Finally, the current challenges and opportunities for application of NCBMs in stable LMAs are also proposed to facilitate their further development.
This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver ***,we establish a lateral dynamic model considering...
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This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver ***,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual ***,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown *** whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function ***,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and *** dynamic models are incorporated to ensure physical realizability of designed allocation ***,comparative experimental results validate the effectiveness of the designed control system and control allocation *** NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),*** design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering.
The vibration response and noise caused by subway trains can affect the safety and comfort of *** study the dynamic response characteristics of subway stations and superstructures under train loads with a hard combina...
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The vibration response and noise caused by subway trains can affect the safety and comfort of *** study the dynamic response characteristics of subway stations and superstructures under train loads with a hard combination,a numerical model is developed in this *** indoor model test verified the accuracy of the numerical *** influence laws of different hard combinations,train operating speeds and modes were studied and evaluated *** results show that the frequency corresponding to the peak vibration acceleration level of each floor of the superstructure property is concentrated at 10–20 *** vibration response decreases in the high-frequency parts and increases in the lowfrequency parts with increasing distance from the ***,the factors,such as train operating speed,operating mode,and hard combination type,will affect the vibration of the *** vibration response under the reversible operation of the train is greater than that of the unidirectional *** operating speed of the train is proportional to its vibration *** vibration amplification area appears between the middle and the top of the superstructure at a higher train *** vibration acceleration level will exceed the limit value of relevant regulations,and vibration-damping measures are *** the scope of application,this study provides some suggestions for constructing subway stations and superstructures.
Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing *** are highly susce...
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Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing *** are highly susceptible to framework charge,which plays a significant role in selective ***,ionic porous frameworks can be divided into two *** of them is composed of a charged backbone and counter *** framework with zwitterionic channels is another *** is composed of regular and alternating arrangements of cationic and anionic building ***,we report a hydrogen-bonded ionic framework （HIF） of{（CN3H6）2[Ti（μ2–O）(SO4)2]}_nwith 1D channel exhibits unique adsorption selectivity for Ar against N2and *** functional theory （DFT） results suggest that CO2cannot be adsorbed by HIF at the experimental temperature due to a positive adsorption free *** addition,due to a relatively large diffusion barrier at 77 K,N2molecules hardly diffuse in HIF channels,while Ar has a negligible diffusion *** unique net positively-charged space in the channel is the key to the unusual phenomena,based on DFT simulations and structural *** findings in this work proposes the new adsorption mechanism and provides unique perspective for special separation applications,such as isotope and noble gasses separations.
Poly（ethylene oxide）-based polymer all-solid-state lithium metal batteries（ASSLBs） have received widespread attention due to their low cost,good process ability,and high energy ***,the growth of Li dendrites withi...
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Poly（ethylene oxide）-based polymer all-solid-state lithium metal batteries（ASSLBs） have received widespread attention due to their low cost,good process ability,and high energy ***,the growth of Li dendrites within polymer solid-state electrolytes damages the reversibility of Li anodes and still impedes their widespread *** efficient strategy is to construct a superior solid electrolyte ***,a stable interface enriched with Li3N and LiF is in-situ formed between Li anode and a terna ry salt *** terna ry salt electrolyte is innovatively designed by introducing lithium bis（trifluoromethane sulfonyl）imide（LiTFSI）,lithium bis（fluorosulfonyl）imide（LiFSI）,and LiNO3to poly（ethylene oxide） *** characterization indicates that LiNO3and LiFSI contribute to forming a Li3N-LiF-enriched interface and meanwhile LiTFSI ensures excellent ***,among various Li compound components,Li3N has high ionic conductivity,which is beneficial for reducing overpotential,while LiF has high interfacial energy which can enhance nucleation energy and suppress the formation of Li *** experimental results show that ASSLBs coupled with LiFePO4cathode display extremely excellent cycle stability approximately 2200 cycles at 2 C,with a final and corresponding discharge specific capacity of 96.7 mA h g-1. Additionally,a schematic illustration of the working mechanism for the Li3N-LiF interface is proposed.
Upcycling of plastic waste into N-containing compound is a novel and attractive strategy for its disposal and will opens up a promising direction for the production of value-added ***,an efficient strategy for the dep...
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Upcycling of plastic waste into N-containing compound is a novel and attractive strategy for its disposal and will opens up a promising direction for the production of value-added ***,an efficient strategy for the depolymerization-amination of polyphenylene oxide(PPO)into 2,6-dimethyl aniline is developed over a simple Pt/CeO_(2) *** C–O linkages of PPO can be selectively broken,producing 2,6-dimethyl phenol and then hydrogenated and aminated to 2,6-dimethyl cyclohexylamine over the Pt/CeO_(2) ***,2,6-dimethyl aniline was produced with high selectivity through the dehydrogenation of 2,6-dimethyl cyclohexylamine in the same *** can be used as the hydrogen-acceptor in the dehydrogenation step and enhance the selectivity of target *** N-containing compound,2,6-dimethyl aniline,is obtained and separated after HCl ***,the Pt/CeO_(2) catalyst exhibit remarkable stability and can sustainably catalyze the synthesis of 2,6-dimethyl aniline in several cycles.
Iron ore pellets,as one of the main charges of blast furnaces,have a greater impact on the CO_(2)emission reduction and stable operation of blast *** isothermal reduction behavior of the pellets obtained from a Chines...
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Iron ore pellets,as one of the main charges of blast furnaces,have a greater impact on the CO_(2)emission reduction and stable operation of blast *** isothermal reduction behavior of the pellets obtained from a Chinese steel plant was studied in the gas mixtures of CO and N_(2).The results showed the reduction process is divided into two *** reduction in the initial stage(time t≤40 min)is cooperatively controlled by internal diffusion and interface chemical reactions with the activation energy of 30.19 and 16.67 kJ/mol,*** controlling step of the reduction in the final stage(t>40 min)is internal diffusion with the activation energy of 34.60 kJ/*** reduction process can be described by two equations obtained from kinetic *** reduction degree can be predicted under different temperatures and time,and the predicted results showed an excellent correlation with the experimental *** reduction mechanisms were confirmed by the analysis of the scanning electron microscope equipped with an energy dispersive spectrometer and optical microscope.
Near-eutectic Al-Si alloys are widely used in automotive manufacturing due to their superior wear resistance and high temperature *** of high Si content,the grain refinement of near-eutectic Al-Si alloy has been a pro...
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Near-eutectic Al-Si alloys are widely used in automotive manufacturing due to their superior wear resistance and high temperature *** of high Si content,the grain refinement of near-eutectic Al-Si alloy has been a problem for many *** this study,the effect of deep cryogenic treatment(DCT)on the microstructure and mechanical properties of Al-12Si-4Cu-2Ni-Mg alloy with addition of Al-Ti-C-B master alloy was fully *** show that the average grain size of the alloy is greatly reduced from 0.92 mm to 0.50 mm,and the eutectic Si and Al7Cu4Ni precipitates are spheroidized and refined in Al-12Si-4Cu-2Ni-Mg after DCT for 24 h and aging *** these changes of microstructures result in a significant increment of about 22.5%in elongation and a slight enhancement of about 6.8%in tensile ***,the refinement of microstructure also significantly improves the fatigue life of the alloy.
Detonation performance is crucial for evaluating the power of high explosives(HEs),and the equation of state(EOS)that accurately describes the high-temperature,high-pressure,and high-temperature,medium-pressure states...
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Detonation performance is crucial for evaluating the power of high explosives(HEs),and the equation of state(EOS)that accurately describes the high-temperature,high-pressure,and high-temperature,medium-pressure states of detonation products is key to assessing the damage efficiency of these energetic *** article examines the limitations of the VLW EOS in representing the thermodynamic states of explosive detonation gas products under high-temperature and medium-to high-pressure conditions.A new gas EOS for detonation products,called VHL(Virial-Han-Long),is *** accuracy of VHL in describing gas states under high-temperature and medium-to high-pressure conditions is verified,and its performance in evaluating explosive detonation and working capabilities is *** results demonstrate that VHL exhibits high precision in calculating detonation ***,the detonation performance of three new HEs(ICM-101,ONC,and TNAZ)was calculated and compared to traditional HEs(TATB,CL-20,and HMX).The results indicate that ONC has superior detonation performance compared to the other explosives,while ICM-101 shows a detonation velocity similar to CL-20 but with slightly lower detonation *** detonation characteristics of TNAZ are comparable to those of the standard HE *** the perspective of products,considering the comprehensive work performance(mechanical work and detonation heat),both ONC and ICM-101demonstrate relatively superior performance.
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