To address nonlinearity, strong coupling, and disturbances in fighter aircraft attitude control, this paper proposes an intelligent control method based on multi-agent deep deterministic policy gradient (MADDPG) and l...
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Non-aqueous absorbents(NAAs)have attracted increasing attention for CO_(2)capture because of their great energy-saving *** diamines which can provide high CO_(2)absorption loading are promising candidates for formulat...
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Non-aqueous absorbents(NAAs)have attracted increasing attention for CO_(2)capture because of their great energy-saving *** diamines which can provide high CO_(2)absorption loading are promising candidates for formulating NAAs but suffer disadvantages in *** this study,a promising strategy that using tertiary amines(TAs)as proton-transfer mediators was proposed to enhance the regenerability of an aminoethylethanolamine(AEEA,diamine)/dimethyl sulfoxide(DMSO)(A/D)***,some employed TAs such as N,N-diethylaminoethanol(DEEA),N,N,N’,N’’,N’’-pentamethyldiethylenetriamine(PMDETA),3-dimethylamino-1-propanol(3DMA1P),and N,N-dimethylethanolamine(DMEA)enhanced not only the regenerability of the A/D NAA but also the CO_(2)absorption ***,the CO_(2)absorption loading and cyclic loading were increased by about 12.7%and 15.5%-22.7%,*** TA-enhanced CO_(2)capture mechanism was comprehensively explored via nuclear magnetic resonance technique and quantum chemical *** CO_(2)absorption,the TA acted as an ultimate proton acceptor for AEEA-zwitterion and enabled more AEEA to form carbamate species(AEEACOO-)to store CO_(2),thus enhancing CO_(2)*** CO_(2)desorption,the TA first provided protons directly to AEEACOO-as a proton donor;moreover,it functioned as a proton carrier and facilitated the low-energy step-wise proton transfer from protonated AEEA to AEEACOO-.Consequently,the presence of TA made it easier for AEEACOO-to obtain protons to decompose,resulting in enhanced CO_(2)*** a word,introducing the TA as a proton-transfer mediator into the A/D NAA enhanced both the CO_(2)absorption performance and the regenerability,which was an efficient way to“kill two birds with one stone”.
Both bulk stress(σ_(i i))and stress path(SP)significantly affect the transportation characteristics of deep gas during reservoir pressure ***,the experimental study of horizontal stress unloading on seepage behavior ...
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Both bulk stress(σ_(i i))and stress path(SP)significantly affect the transportation characteristics of deep gas during reservoir pressure ***,the experimental study of horizontal stress unloading on seepage behavior of gas-bearing coal under constantσi i-constraints is *** results show that coal permeability is affected by horizontal stress anisotropy(σ_(H)≠σh),and the contribution of minor horizontal stress to permeability is related to the differential response of horizontal *** slippage phenomenon is prominent in deep high-stress regime,especially in low reservoir pressure.σ_(i i)and SP jointly determine the manifestation of slippage effect and the strength of stress sensitivity(γ)of *** reservoir implies an incremental percentage of slip-based permeability,and SP weakens the slippage effect by changing the elastic–plastic state of ***,γis negatively correlated with slippage *** the Walsh model,narrow(low aspect-ratio)fractures within the coal under unloading SP became the main channel for gas seepage,and bring the effective stress coefficient of permeability(χ)less than 1 for both low-stress elastic and high-stress damaged *** the raise of the effective stress,the effect of pore-lined clay particles on permeability was enhanced,inducing an increase inχfor highstress elastic coal.
In this study,three kinds of radical scavenger Chimassorb 944,Tinuvin 622,and Tinuvin 770 are used to suppress the growth of electrical trees in cross-linked polyethylene(XLPE)with transient superimposed voltage under...
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In this study,three kinds of radical scavenger Chimassorb 944,Tinuvin 622,and Tinuvin 770 are used to suppress the growth of electrical trees in cross-linked polyethylene(XLPE)with transient superimposed voltage under the temperature *** tree morphology,tree length,accumulated damage,and time to breakdown are used to investigate the effect of radical scavenger on the electrical treeing *** is found that under the temperature gradient caused by the temperature rise on the high voltage side,only Tinuvin 622 can always suppress the electrical tree as the temperature gradient *** the temperature gradient caused by the temperature rise on the ground side,the three radical scavengers can all suppress the electrical *** breakdown of electrical tree exhibits the strong DC polarity ***,energy levels of these three radical scavengers are calculated through quantum chemistry,and the results indicate that radical scavengers have greater electron affinity,smaller ionisation energy,and smaller energy gap than *** to the surface potential decay test results at 60℃,it is found that all three radical scavengers can introduce deep *** different performances of radical scavengers under different temperature gradients and voltages are determined by the trap distribution characteristics,the molecular structure and chemical reaction of the additives *** is concluded that Tinuvin 622 has potential for use in high voltage direct current XLPE cable application.
Methane in-situ explosive fracturing technology produces shale debris particles within fracture channels,enabling a self-propping effect that enhances the fracture network conductivity and long-term *** study employs ...
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Methane in-situ explosive fracturing technology produces shale debris particles within fracture channels,enabling a self-propping effect that enhances the fracture network conductivity and long-term *** study employs X-ray computed tomography(CT)and digital volume correlation(DVC)to investigate the microstructural evolution and hydromechanical responses of shale self-propped fracture under varying confining pressures,highlighting the critical role of shale particles in maintaining fracture *** indicate that the fracture aperture in the self-propped sample is significantly larger than in the unpropped sample throughout the loading process,with shale particles tending to crush rather than embedded into the matrix,thus maintaining flow *** confining pressure increases,contact areas between fracture surfaces and particles expand,enhancing the system's stability and compressive *** analyses show flow paths becoming increasingly concentrated and branched under high *** resulted in a significant reduction in connectivity,restricting fracture permeability and amplifying the nonlinear gas flow *** study introduces a permeability-strain recovery zone and a novel sensitivity parameter m,delineating stress sensitivity boundaries for permeability and normal strain,with m-value increasing with stress,revealing four characteristic *** findings offer theoretical support for optimizing fracturing techniques to enhance resource extraction efficiency.
The CeO_(2)-TiO_(2)@MnO_(x) catalyst was prepared by the co-precipitation method and applied to the photothermocatalysis system of ethyl acetate and NO simultaneous degradation under H_(2)O at low temperature,which in...
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The CeO_(2)-TiO_(2)@MnO_(x) catalyst was prepared by the co-precipitation method and applied to the photothermocatalysis system of ethyl acetate and NO simultaneous degradation under H_(2)O at low temperature,which introduced Ce into TiO_(2)@MnO_(x) hollow sptrera *** optimum TiO_(2)/MnO_(x) ratio and Ce introducing amount were obtained in the *** of them,the NO and ethyl acetate conversion percentage of TiO_(2)@MnO_(x)(n_(Mn):n_(Ti)=40:40)is 74%and 62%at 240℃,***_(2)-TiO_(2)@MnO_(x)(n_(Mn):n_(Ce)=1:1)exhibits the best catalytic performance,its efficiency for NO conversion is 83%and the conversion of ethyl acetate reaches 72%at 240℃.In addition,it is confirmed that the Cedoped nanocomposites have more uniform dispersion through various characterization and analysis ***,these catalysts have a large specific surface area as well as a large number of surface-active oxygen and oxygen *** can further improve the catalytic performance based on the adjusted ratio of active ***,this work investigated the relationship between multi-metal interactions and catalytic performance in the presence of H_(2)***,the possible reaction pathways for the simultaneous removal of NO and ethyl acetate were explored in our system.
The persistence, bioaccumulation, and toxicity of perfluorinated and polyfluoroalkyl substances (PFASs), along with their concentrations in the environment and humans, have attracted global attention. However, so far,...
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Hybrid teaching combines traditional teaching and flipped classroom, which is a new teaching mode with the advantages of both modes. In hybrid teaching mode, reasonable allocation of credit hours between traditional t...
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Aero-optic imaging deviation research is carried out for infrared-guided vehicle with cone-head side window,with a focus on the propagation characteristics of light in an aero-optic flow *** the light entering the aer...
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Aero-optic imaging deviation research is carried out for infrared-guided vehicle with cone-head side window,with a focus on the propagation characteristics of light in an aero-optic flow *** the light entering the aero-optic flow field from the free-stream should be close to the normal,numerous data indicate that the light is refracted away from the *** paper divides the aero-optic flow field into two parts and uses the gas density distribution in the aero-optic flow field to propose the hypothesis that there are two modes of refraction when light propagates through the flow *** results show that light propagates from the optically denser medium to the optically thinner medium after passing through the shock wave and eventually leads to refraction away from the normal when the light enters the aero-optic flow field.
In the process of oil production, the submerged oil motor works 1-3 km downhole and is connected to the inverter by a long-wire cable, which generates overvoltage at the motor end due to the problem of matching the im...
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