Zwitterions （ZIs） are considered as an ideal,novel ionic conductive medium due to their high dipole moment and good solubility of lithium ***,the strong interactions between ZIs and Li+severely hinder Li+***,a quasi...
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Zwitterions （ZIs） are considered as an ideal,novel ionic conductive medium due to their high dipole moment and good solubility of lithium ***,the strong interactions between ZIs and Li+severely hinder Li+***,a quasi-solid electrolyte （MSQSE-2Na） was fabricated by adding sodium bis（fluorosulfonyl）imide （NaFSI） to sulfobetaine methacrylate （SBMA,a ZI） based polymerization ***+occupies the –SO3-site in SBMA prior to Li+,which weakens the self-crosslinking of SBMA and frees the Li+bound to the polymer ***,the polymer conformation of MSQSE-2Na changes to a relaxed,homogeneous "sea-island" ***,Na+,due to its electron-withdrawing effect,decreases the electron cloud density of the polymer segments,building a weakly coordinated environment in ***,MSQSE-2Na exhibits excellent ionic conductivity of 7.38×10-4S cm-1and a high Li+transference number of 0.632 at 25°*** （-） Li|MSQSE-2Na|Li （+） cells exhibit super stability,sustaining operation for over *** （-） Li|MSQSE-2Na|LiFePO4（+） cells demonstrate outstanding charge/discharge reversibility with a Coulombic efficiency exceeding 99.9%over 270 cycles（≈4500 h）,with a capacity retention of 70.0%.This work proposes a new design concept for regulating the polymer conformation and charge characteristics through competitive coordination,thereby advancing the application of ZI-based polymer electrolytes in lithium metal batteries.
Biomass-derived hard carbon is becoming promising anodes for potassium-ion batteries（PIBs） thanks to their resource ***,it is a big challenge to improve the charge carrier kinetics of the disordered carbon lattice i...
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Biomass-derived hard carbon is becoming promising anodes for potassium-ion batteries（PIBs） thanks to their resource ***,it is a big challenge to improve the charge carrier kinetics of the disordered carbon lattice in hard ***,confined pitch-based soft carbon in pollen-derived hard carbon（PSC/PHC） is synthesized by vapor deposition strategy as anodes for *** ordered pitch-based soft carbon compensates for the short-range electron conduction in hard carbon to enhance the charge transfer kinetics,and the externally disordered pollen-derived hard carbon alleviates the volume change of soft carbon during *** from the synergistic effect of soft and hard carbon,as well as the reinforced structure of order-in-disordered carbon,the PSC/PHC obtained with deposition time of 0.5 h（PSC/PHC-0.5） displays an excellent rate capability(148.7 mAh g-1at 10 A g-1) and superb cycling stability(70% retention over 2000 cycles at 1 A g-1).This work offers a unique insight in tuning the microcrystalline structure of soft-hard carbon anode for advanced PIBs.
Fully conjugated covalent organic frameworks （COFs） are widely used in *** COF with–ph–NH2edge poly（1,4-phenyldiazo porphyrin cobalt）(A-PpazoPorCo) is synthesized by adjusting the molar ratio of the reaction mat...
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Fully conjugated covalent organic frameworks （COFs） are widely used in *** COF with–ph–NH2edge poly（1,4-phenyldiazo porphyrin cobalt）(A-PpazoPorCo) is synthesized by adjusting the molar ratio of the reaction material,and exhibits high delocalization energy to significantly enhance thermal *** nitrogen in the azo bond improves the adsorption capacity for ORR and OER catalytic intermediates,while the–ph–NH2group further increases the electron cloud density at the Co–N4center in *** functional theory （DFT） calculations reveal that the strong electron-donating–ph–NH2groups and the electron-donating azo bonds form an electron donor-π-electron acceptor （D-π-A） structure,which further enhances the electron cloud *** strongπ-πinteraction between A-PpazoPorCo and three-dimensional graphene （3D-G） significantly boosts the oxygen catalytic performance of the A-PpazoPorCo/*** catalytic ORR half-wave potential(E1/2) of A-PpazoPorCo/3D-G can reach 0.880 V *** total overpotential (ΔE=Ej=10-E1/2) is 0.617 V,demonstrating excellent bifunctional oxygen catalytic *** efficient oxygen catalytic performance indicates that A-PpazoPorCo/3D-G has the potential for application in fuel cells cathodes and overall water splitting anodes.
Data-driven process monitoring is an effective approach to assure safe operation of modern manufacturing and energy systems, such as thermal power plants being studied in this work. Industrial processes are inherently...
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Data-driven process monitoring is an effective approach to assure safe operation of modern manufacturing and energy systems, such as thermal power plants being studied in this work. Industrial processes are inherently dynamic and need to be monitored using dynamic algorithms. Mainstream dynamic algorithms rely on concatenating current measurement with past data. This work proposes a new, alternative dynamic process monitoring algorithm, using dot product feature analysis(DPFA).DPFA computes the dot product of consecutive samples, thus naturally capturing the process dynamics through temporal correlation. At the same time, DPFA's online computational complexity is lower than not just existing dynamic algorithms, but also classical static algorithms(e.g., principal component analysis and slow feature analysis). The detectability of the new algorithm is analyzed for three types of faults typically seen in process systems:sensor bias, process fault and gain change fault. Through experiments with a numerical example and real data from a thermal power plant, the DPFA algorithm is shown to be superior to the state-of-the-art methods, in terms of better monitoring performance(fault detection rate and false alarm rate) and lower computational complexity.
The oxygen evolution reaction（OER） is crucial for the electrocatalytic water electrolysis into oxygen and hydrogen,but the fourelectron transfer process hinders the OER *** realize the highly efficient water splitti...
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The oxygen evolution reaction（OER） is crucial for the electrocatalytic water electrolysis into oxygen and hydrogen,but the fourelectron transfer process hinders the OER *** realize the highly efficient water splitting,the nonprecious metal-based electrodes that can optimize the adsorption energy of intermediates and generate H2with low overpotential and robust stability are ***,we report a surface modification strategy to grow the trimetallic FeCoNi hydroxide on the amine linkersgrafted carbon cloth（CC-NH2@FeCoNi） by ***-NH2@FeCoNi possesses a superhydrophilic/superaerophobic surface,which could significantly enhance the mass transfer,and meanwhile promote the in situ generation of MOOH active ***,the superhydrophilic surface could facilitate the adsorption of abundant OH-ions,and repel the Cl-ions via electrostatic repulsive force during seawater ***,compared with the CC@FeCoNi that grown on the pure CC（320 mV）,the CC-NH2@FeCoNi needs an obviously smaller overpotential of 270 mV to achieve a current density of 100 mA cm-2,and meanwhile it exhibits a superior durability for 100 h at a current density of 200 m A cm-2in both alkaline water and *** strategy could be even applied universally in the preparation of other nonprecious metal hydroxides for efficient OER catalysis.
Geldart Group C powders are inherently cohesive due to the strong interparticle forces,leading to severe agglomeration and poor fluidization *** this study,fluidization of nano-modulated Group C particles was investig...
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Geldart Group C powders are inherently cohesive due to the strong interparticle forces,leading to severe agglomeration and poor fluidization *** this study,fluidization of nano-modulated Group C particles was investigated *** particles,also known as Group C+particles,were obtained through the nanoparticle modulation technique,with which a small fraction of nanoparticles were vigorously mixed with Group C particles so that they are adhered to the surface of the much larger Group C *** modification,the cohesiveness of Group C+particle was significantly weakened,and therefore these particles could exhibit much better fluidization ***,the still existing cohesion resulted in the formation of small agglomerates within the *** understand the internal agglomeration mechanisms of Group C+particles and their impact on fluidization behaviors,a new drag model was proposed based on experimental results and the postulation of particle *** numerical results of the cases employing the new drag model agreed well with the experimental data in terms of total and dense phase *** findings revealed the drag mechanism associated with modified Group C particles,contributing to the understanding of ultrafine particle fluidization.
Catalytic hydrogenation of CO_(2)to ethanol is a promising solution to address the greenhouse gas(GHG)emissions,but many current catalysts face efficiency and cost *** based catalysts are frequently examined due to th...
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Catalytic hydrogenation of CO_(2)to ethanol is a promising solution to address the greenhouse gas(GHG)emissions,but many current catalysts face efficiency and cost *** based catalysts are frequently examined due to their abundance,cost-efficiency,and effectiveness in the reaction,where managing the Co^(0)to Co^(δ+)ratio is *** this study,we adjusted support nature(Al_(2)O_(3),MgO-MgAl_(2)O_(4),and MgO)and reduction conditions to optimize this balance of Co^(0)to Co^(δ+)sites on the catalyst surface,enhancing ethanol *** selectivity of ethanol reached 17.9%in a continuous flow fixed bed micro-reactor over 20 mol%Co@MgO-MgAl_(2)O_(4)(CoMgAl)catalyst at 270°C and 3.0 MPa,when reduced at 400°C for 8 *** results coupled with activity analysis confirmed that mild reduction condition(400°C,10%H_(2)balance N_(2),8 h)with intermediate metal support interaction favoured the generation of partially reduced Co sites(Co^(δ+)and Co^(0)sites in single atom)over MgO-MgAl_(2)O_(4)surface,which promoted ethanol synthesis by coupling of dissociative(CHx^(∗))/non-dissociative(CHxO^(∗))intermediates,as confirmed by density functional theory ***,the CoMgAl,affordably prepared through the coprecipitation method,offers a potential alternative for CO_(2)hydrogenation to yield valuable chemicals.
Gas-liquid-solid mini-fluidized beds known for high efficiency with controllable mass and heat transfer characteristics,have good application prospects in fields such as multiphase reaction process enhancement and int...
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Gas-liquid-solid mini-fluidized beds known for high efficiency with controllable mass and heat transfer characteristics,have good application prospects in fields such as multiphase reaction process enhancement and intrinsic kinetic *** three-phase mini-flow systems,the bed wall has a significant impact on spatiotemporal distribution of multi-phase flow structure,which influence the motion state of dispersed phase,make predicted phase holdup and residence time deviate from experimental ***,current research on the quantitative impact of bed walls on flow structures is still limited,which hinders the optimization design and industrial application of such *** this work,a meso-scale flow model of gas-liquid-solid mini-fluidized beds considering macro-scale effects between bed wall and flow is developed based on the principle of meso-scale science and introducing semi-theoretical formulas that take the effects of bed walls on particles and bubbles into *** calculated values of this model are in good agreement with experimental data,where prediction of phase holdup fits well with experimental results,the deviation of bubble size and terminal velocity are within 10%.Compared to existing models,this model demonstrates a higher level of accuracy in predicting the flow patterns of mini-fluidized beds,particularly those with pronounced wall *** research has laid a foundation for the design,scale-up and industrial application of mini-fluidized bed reactors.
Gas-liquid-solid circulating fluidized bed(GLSCFB)is an important type of chemical *** complex mesoscale flow structure of GLSCFB was described through the mesoscale flow structure parameters based on the energy-minim...
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Gas-liquid-solid circulating fluidized bed(GLSCFB)is an important type of chemical *** complex mesoscale flow structure of GLSCFB was described through the mesoscale flow structure parameters based on the energy-minimization multi-scale(EMMS)*** liquid-solid drag force model(Drag-ls model)was proposed and it was found that the drag coefficient between liquid and solid in three-phase systems increased compared to liquid-solid two-phase systems because of the influence of gas *** gas-solid drag force model(Drag-gs model)was proposed based on a modified unified wake ***,the combination of EMMS model and computational fluid dynamics(CFD)in GLSCFB was implemented,and the dynamic evolution process of particle clusters and distributions of gas holdup and solid holdup in GLSCFB were simulated more accurately by the *** simulation results indicate that the drag forces exerted on the solid phase by both the liquid and gas phases are coupled and mutually influence each *** simulated values of solid holdup may deviate from the experimental values if the interactions between the gas-solid and liquid-solid phases are corrected *** the average solid holdup of the bed is low,the mesoscale phenomena such as particle aggregation are not *** the solid holdup increases,there is a significant phenomenon of particle aggregation in the *** particles undergo a spatiotemporal evolution process of forming elongated clusters with high solid holdup,spherical clusters with high solid holdup,and clusters with low solid holdup which has large surface areas.
The large and uneven grain size of anhydrous magnesium carbonate (MgCO_(3)) seriously restricts its application ranges and performances. In this study, we proposed a controllable and cost-effective strategy to synthes...
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The large and uneven grain size of anhydrous magnesium carbonate (MgCO_(3)) seriously restricts its application ranges and performances. In this study, we proposed a controllable and cost-effective strategy to synthesize uniform small-sized MgCO_(3) from Mg^(2+) concentrated seawater brine in the absence of crystal modifiers. In this process, solid NaOH was directly added to Mg^(2+) concentrated seawater brine to completely and rapidly convert Mg^(2+) to magnesium hydroxide (Mg(OH)_(2)) nanoparticles. These nanoparticles are redispersed in water to form the colloidal system, where Mg(OH)_(2) nanoparticles hydrothermally reacts with urea to obtain uniform small-sized MgCO_(3) particles. The influence of reaction temperature, reaction time, and the molar ratio of magnesium ions to urea on the synthesis of MgCO_(3) is systematically investigated. In the highly-dispersed and stable colloidal system, Mg(OH)2 nanoparticles could exert an effective and sustained retarding effect on the hydrolysis rate of urea by attracting free water, resulting in the controllable release of NH_(4)^(+), CO_(3)^(2−), and Mg^(2+). This study presents a simple route to realize the controllable synthesis of uniform small-sized MgCO_(3) particles, and demonstrates the feasibility of using MgCO_(3) as an ideal filler for enhancing the performance of polymers as well as an ideal precursor for high-purity MgO production.
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