The path to searching for sustainable energy has never stopped since thedepletion of fossil fuels can lead to serious environmental pollution andenergy *** water electrolysis to produce hydrogen has beenproven to be a...
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The path to searching for sustainable energy has never stopped since thedepletion of fossil fuels can lead to serious environmental pollution andenergy *** water electrolysis to produce hydrogen has beenproven to be a prioritized approach for green resource *** is highlycrucial to explore inexpensive and high-performance electrocatalysts foraccelerating hydrogen evolution reaction(HER)and apply them to industrialcases on a large ***,we summarize the different mechanisms of HERin different pH settings and review recent advances in ***,based on the previous efforts,we discuss severaluniversal strategies for designing pH-independent catalysts and showdirections for the future design of pH-universal catalysts.
The nitridation reaction of calcium carbide and N_(2) at high temperatures is the key step in the production of ***,the challenges faced by this process,such as high energy consumption and poor product quality,are mai...
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The nitridation reaction of calcium carbide and N_(2) at high temperatures is the key step in the production of ***,the challenges faced by this process,such as high energy consumption and poor product quality,are mainly attributed to the lack of profound understanding of the *** study aimed to improve this process by investigating the non-isothermal kinetics and reaction characteristics of calcium carbide nitridation reaction at different heating rates(10,15,20,and 30℃·min^(-1))using thermogravimetric *** kinetic equation for the nitridation reaction of additive-free calcium carbide sample was obtained by combining model-free methods and model-fitting *** effect of different calcium-based additives(CaCl_(2) and CaF_(2))on the reaction was also *** results showed that the calcium-based additives significantly reduced reaction temperature and activation energy E_(a) by about 40% with CaF_(2) and by 55%-60% with CaCl_(2).The reaction model f(α)was also changed from contracting volume(R3)to 3-D diffusion models with D3 for CaCl_(2) and D4 for CaF_(2).This study provides valuable information on the mechanism and kinetics of calcium carbide nitridation reaction and new insights into the improvement of the lime-nitrogen process using calcium-based additives.
This study investigates microstructure, hydrogen diffusion properties, and stress corrosion cracking(SCC) behavior of Q345R steel subject to pre-applied strains of 1 %, 3 %, and 5 %. The relationship between microstru...
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This study investigates microstructure, hydrogen diffusion properties, and stress corrosion cracking(SCC) behavior of Q345R steel subject to pre-applied strains of 1 %, 3 %, and 5 %. The relationship between microstructure and SCC susceptibility in hydrofluoric acid(HF) vapor is examined. It is found that pre-strain cannot change the microstructure of Q345R steel but increases dislocation density. The increasing SCC sensitivity of Q345R steel in HF vapor is associated with the dislocation density induced by pre-strain. With increasing pre-strain, dislocation density and reversible hydrogen trap increase, and interaction between hydrogen and dislocation accelerates hydrogen-induced SCC. In addition, irreversible hydrogen traps caused by high pre-strain can severely aggravate hydrogen-induced SCC, resulting in high SCC vulnerability.
The cerium-silicate pillared MWW zeolites are fabricated by introducing Ce species into the silica pillars within adjacent MWW layers through a liquid-phase pillaring method,and the multiple-layer structure of MWW zeo...
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The cerium-silicate pillared MWW zeolites are fabricated by introducing Ce species into the silica pillars within adjacent MWW layers through a liquid-phase pillaring method,and the multiple-layer structure of MWW zeolites is well ***,it's found that these Ce^(3+)species can produce the Bronsted acid sites by the dissociation of water molecules owing to the electrostatic field of Ce^(3+)cations,the splitting of water molecules occurs following[Ce(H_2O)_n]^(3+)■Ce[(OH)(H_2O)_(n-1)]^(2+)+H^(+)equation based on the Plank-Hirschler mechanism,leading to superior activity of resultant cerium-silicate pillared MWW zeolites in the alkylation between benzene with ***,the additional Ce species located in the silica pillars can be easily accessed by guest molecules due to the presence of mesopores between neighboring MWW layers,which can strongly active benzene molecules by polarization effect,and dodecyl carbenium ions are preferred to attack the carbon atoms located in activated benzene molecules,resulting in the long lifetime of cerium-silicate pillared MWW zeolites since the oligomerization of long-chain olefins is *** harsh reaction conditions(benzene/1-dodecene=10,WHSV=20 h^(-1)),the optimized cerium-silicate pillared MWW zeolite shows outstanding activity(>40%)and excellent selectivity(>85%)of 2-LAB in the alkylation of benzene with 1-dodecene.
Regarding sugar and salt crystallization with large single crystals,the agglomerate thermodynamics and geometric morphologies,not the dynamics,dominate the particle size distribution(PSD).To consider this issue,a PSD ...
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Regarding sugar and salt crystallization with large single crystals,the agglomerate thermodynamics and geometric morphologies,not the dynamics,dominate the particle size distribution(PSD).To consider this issue,a PSD design model is proposed for limited large crystal *** this model,the agglomeration thermodynamic criticality is determined by estimating the adhesion and dispersion forces between single *** geometric agglomerate morphologies are described by corresponding single crystal units stacking with *** seed well-controlled of population,the key parameters of PSD(D01,D50 and D99)are precisely *** erythritol,the model design accuracies are 92%–99%in the 1.2 L and 10 L crystallizers,indicating that it can design PSD at various crystallization *** the general research attention to microcrystal agglomeration kinetics(mostly active pharmaceutical ingredients),this model effectively guides the sugar and salt PSD design with limited large crystal agglomeration.
Chiral nanomaterials have distinct chiroptical properties of preferential interactions to circularly polarized ***-based biosensors have emerged for detection of biomolecules,ions and cells in recent *** review provid...
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Chiral nanomaterials have distinct chiroptical properties of preferential interactions to circularly polarized ***-based biosensors have emerged for detection of biomolecules,ions and cells in recent *** review provides an extensive overview of biosensors based on chiral nanomaterials,starting with approaches to chiral nanomaterials construction in terms of fabrication *** of chiral nanomaterials and their biosensor applications is presented for different material types,with special emphasis on the role and importance of material properties and signal generation in *** assessed the technological prospects of the emerging fields of chiral construction,circularly polarized luminescence,Raman optical activity and so on along with their current *** venues for future research on chiral nanomaterials in fabrication,biosensing,disease diagnosis and treatment are also presented in the review.
The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)*** the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulat...
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The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)*** the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulate such a complex loop system due to limitations of coarse-grained(CG)models,computing software,and *** this study,a newly proposed soft-shell CG-DPM model with a CG ratio of up to 800 is used to simulate a 3.5 Mt/a industrial-scale MIP reactor-regenerator *** solid fraction distribution obtained is found to agree well with in-situ *** properties including the distribution of solid fraction,gas and solid velocity,standard derivation of solid fraction with time,temporal distribution of the flow field,and particle residence time distribution are measured in the simulation,which are meaningful to better design and operate such systems in the future.
A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots(NSCQDs)nan...
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A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots(NSCQDs)nanoparticles on the surface of sheet cobalt-based metal-organic framework(Co-MOF)and graphitic carbon nitride(g-C_(3)N_(4),CN).The structure and properties of the obtained catalysts were systematically *** effectively broaden the absorption of Co-MOF and CN in the visible *** new composite photocatalyst has high hydrogen production activity and the hydrogen production rate reaches 6254μmol/(g·h)at pH=*** the same time,NSCQDs synergy Co-MOF/CN composites have good *** four cycles of hydrogen production,the performance remains relatively *** tran sient photocurrent response and Nyquist plot experimental results further demonstrate the improvement of carrier separation efficiency in composite *** semiconductor type(n-type semico nductor)of the single-phase catalyst was determined by the Mott-Schottky test,and the band structure was *** conductive and valence bands of CN are-0.99 and 1.72 eV,respectively,and the conduction and valence bands of Co-MOF are-1.85 and 1.33 eV,*** e mechanism of the photocatalytic reaction can be inferred,that is,Z-type heterojunction is formed between CN an d Co-MOF,and NSCQDs was used as cocatalyst.
There are still some challenges to the vigorous development of aqueous zinc-ion batteries(AZIBs).Among them,the dendrites have severely reduced the coulomb efficiency(CE)and cycle life due to the slow and uneven Zn^(2...
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There are still some challenges to the vigorous development of aqueous zinc-ion batteries(AZIBs).Among them,the dendrites have severely reduced the coulomb efficiency(CE)and cycle life due to the slow and uneven Zn^(2+)transportation kinetics,serious corrosion and hydrogen evolution reaction(HER)at the electrolyte/anode surface/*** zinc dendrites aggravate the interface side reactions,especially at high current density leading to the short circuit,which re-stricts the further application of AZIBs[1].Numerous strategies can effectively suppress zinc dendrites such as interfacial coating construc-tion,electrolyte modification,and separator design,among which the interfacial coating construction method is more suitable for commer-cialization because of its versatility,simplicity and ***,continuous and stable operation of zinc anodes modified via the coating method at high current/capacity is an urgent and important issue to be solved.
Air pollution,including airborne pathogens and particulate matter(PM),has become a prominent issue affecting human health and *** air filtration materials do not meet the requirements for efficient PM capture or do no...
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Air pollution,including airborne pathogens and particulate matter(PM),has become a prominent issue affecting human health and *** air filtration materials do not meet the requirements for efficient PM capture or do not instantly kill pathogens,leading to increased risk of direct/indirect contact transmission and infection due to the accumulation of pathogens during *** nanofibrous membranes have emerged as a promising platform due to their rich porous structure,finer fiber diameters,good internal connectivity,and the ability to easily incorporate active chemicals for antimicrobial *** this review,antimicrobial mechanisms of nanofibrous membranes for air filtration and PM capture mechanisms of nanofibers were firstly investigated,and various types of electrospun nanofibrous membranes with different antimicrobial agents for efficient air filtration were described in detail,including organic antimicrobial agents,inorganic antimicrobial agents and metal-organic *** hope this work could provide a better practical insight for designing novel electrospun nanofibrous membranes with antimicrobial efficacy for efficient air filtration.
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