Lignin-derived hard carbon shows potential as an anode material for sodium-ion batteries(SIBs)due to its high carbon content and aromatic structure,but its limited reversible adsorption sites and low conductivity hind...Lignin-derived hard carbon shows potential as an anode material for sodium-ion batteries(SIBs)due to its high carbon content and aromatic structure,but its limited reversible adsorption sites and low conductivity hinder performance.This study introduces a self-activation strategy to optimize carbon layer stacking and surface functional groups in microporous carbon,significantly enhancing sodium storage capacity and rate performance.By utilizing oxygen-containing functional groups in organic solvent lignin,we induce micropore formation during pyrolysis,effectively regulating graphite domains and closed pores structures without disrupting carbon layer growth.Unstacked graphene layers serve as efficient electron transport channels and expose additional adsorption sites,simultaneously increasing sodium storage capacity and intrinsic conductivity.The resultant S-OLHC demonstrates a remarkable sodium storage capacity of 358 mA h/g at 0.05 A/g after 200 cycles and maintains 231 mA h/g after 1000 cycles at 2 A/g.This strategy eliminates the need for additional pore-forming agents,offering a simpler,more efficient,and environmentally friendly approach compared to traditional activation methods.This work advances the rational design of high-performance biomass-derived hard carbon for SIBs by leveraging inherent structural characteristics and provides a sustainable low-carbon strategy for lignin valorization in renewable energy storage.展开更多
To accurately analyze the impact of casting pores in steel,high-resolution 3D X-ray tomography technology was used to gather detailed statistical information about micropores.These micropores were classified as gas,sh...To accurately analyze the impact of casting pores in steel,high-resolution 3D X-ray tomography technology was used to gather detailed statistical information about micropores.These micropores were classified as gas,shrinkage,and gas-shrinkage pores depending on their formation origin and morphology.Clustering tendencies and affinity parameters were defined to characterize the spatial correlations among these three types of pores.The 3D data from X-ray tomography scans were then integrated into finite element analysis(FEA)software to predict how micropore shape,size,and distribution influence stress distribution within the material.The results show that certain inflection points with small local radii within the cast pores are major contributors to stress concentration.Therefore,cast pores cannot be simply modeled as ideal spherical pores.The sphericity and volume of pores have a significant impact on the stress concentration of the model.Specifically,lower sphericity and larger pore volumes result in higher stress concentrations.Moreover,the internal pores of steel castings exhibit specific global distribution characteristics.Pores located on the surface of the specimen lead to significantly higher stress concentrations compared to those located inside the specimen.展开更多
In this work, four empirical models of statistical thickness, namely the models of Harkins and Jura, Hasley, Carbon Black and Jaroniec, were compared in order to determine the textural properties (external surface and...In this work, four empirical models of statistical thickness, namely the models of Harkins and Jura, Hasley, Carbon Black and Jaroniec, were compared in order to determine the textural properties (external surface and surface of micropores) of a clay concrete without molasses and clay concretes stabilized with 8%, 12% and 16% molasses. The results obtained show that Hasley’s model can be used to obtain the external surfaces. However, it does not allow the surface of the micropores to be obtained, and is not suitable for the case of simple clay concrete (without molasses) and for clay concretes stabilized with molasses. The Carbon Black, Jaroniec and Harkins and Jura models can be used for clay concrete and stabilized clay concrete. However, the Carbon Black model is the most relevant for clay concrete and the Harkins and Jura model is for molasses-stabilized clay concrete. These last two models augur well for future research.展开更多
Micropores of shale are significant to the gas content and production potential of shale, which has been verified in the research of marine shale gas; while, few studies have been conducted on lacustrine shales. This ...Micropores of shale are significant to the gas content and production potential of shale, which has been verified in the research of marine shale gas; while, few studies have been conducted on lacustrine shales. This study collected 42 samples from three wells in the Late Cretaceous Qingshankou Formation of the southern Songliao Basin, NE China, and investigated these samples by the focused ion beam-scanning electron microscope(FIB–SEM) and nitrogen adsorption analysis techniques. Four types of micropores were identified in the samples, i.e., intergranular pore, intracellular pore, organic matter pore and microfracture. The pore structure type is characterized by open slit pores and "ink type" pores which are mainly 1.5–5 nm in diameter with mesopores as the main pores. The mesopores account for 74.01% of the pore volume and 54.68% of the pore surface area. Compared with the lacustrine shales from the Triassic Yanchang Formation in the Ordos Basin and Xujiahe Formation in the Sichuan Basin, the intergranular clay mineral interlayer pores are considered to be the main reservoir space for shale gas storage in the study area, followed by intraparticle pores, organic matter pores and microfractures. Maturity and micropore are the key controlling factors which affect the shale gas content of the Qingshankou Formation in southern Songliao Basin.展开更多
Energy conversion technologies like fuel cells and metal-air batteries require oxygen reduction reaction(ORR)electrocatalysts with low cost and high catalytic activity.Herein,N-doped carbon spheres(N-CS)with rich micr...Energy conversion technologies like fuel cells and metal-air batteries require oxygen reduction reaction(ORR)electrocatalysts with low cost and high catalytic activity.Herein,N-doped carbon spheres(N-CS)with rich micropore structure have been synthesized by a facile two-step method,which includes the polymerization of pyrrole and formaldehyde and followed by a facile pyrolysis process.During the preparation,zinc chloride(ZnCl2)was utilized as a catalyst to promote polymerization and provide a hypersaline environment.In addition,the morphology,defect content and activity area of the resultant N-CS catalysts could be regulated by controlling the content of ZnCl2.The optimum N-CS-1 catalyst demonstrated much better catalytic activity and durability towards ORR in alkaline conditions than commercial 20 wt%Pt/C catalysts,of which the half-wave potential reached 0.844 V vs.RHE.When applied in the Zn-air batteries as cathode catalysts,N-CS-1 showed a maximum power density of 175 mW cm^(-2) and long-term discharging stability of over 150 h at 10 mA cm^(-2),which outperformed 20 wt%Pt/C.The excellent performance could be due to its ultrahigh specific surface area of 1757 m2 g1 and rich micropore channels structure.Meanwhile,this work provides an efficient method to synthesize an ultrahigh surface porous carbon material,especially for catalyst application.展开更多
Based on an equivalent medium approach, this paper presents a model describing the nonlinear propagation of acoustic waves in a viscoelastic medium containing cylindrical micropores. The influences of pores＇ nonlinea...Based on an equivalent medium approach, this paper presents a model describing the nonlinear propagation of acoustic waves in a viscoelastic medium containing cylindrical micropores. The influences of pores＇ nonlinear oscillations on sound attenuation, sound dispersion and an equivalent acoustic nonlinearity parameter are discussed. The calculated results show that the attenuation increases with an increasing volume fraction of micropores. The peak of sound velocity and attenuation occurs at the resonant frequency of the micropores while the peak of the equivalent acoustic nonlinearity parameter occurs at the half of the resonant frequency of the micropores. Furthermore, multiple scattering has been taken into account, which leads to a modification to the effective wave number in the equivalent medium approach. We find that these linear and nonlinear acoustic parameters need to be corrected when the volume fraction of micropores is larger than 0.1%.展开更多
Conjugated microporous polymers have excellent skeleton structures but poor electrical conductivity limits their applications in microwave absorption.To solve this problem,a strategy of molecular expansion and confini...Conjugated microporous polymers have excellent skeleton structures but poor electrical conductivity limits their applications in microwave absorption.To solve this problem,a strategy of molecular expansion and confining polymerization is proposed in this work to synthesize conductive hyper-crosslinked conjugated microporous polymer.The topology of the conjugated microporous polymer is changed into a three-dimensional skeleton structure with high specific surface area by using molecular expansion technique,and the controlled growth of polypyrrole in the channel constructs a unique network structure.The balance of excellent composite backbone structure,proper conductivity,attenuation capability and impedance matching enable the material to exhibit electromagnetic wave absorption performance.As a result,with low filler loading of 10 wt%,a strongest reflection loss of-52.68 d B and a maximum effective bandwidth of 5.76 GHz.Additionally,CST simulations of the radar scattering cross section have been carried out to verify the excellent material properties.This study provides new concepts for new conductive polymers and broadens the application of hyper-crosslinked conjugated microporous polymer in the field of electromagnetic wave absorption.展开更多
The healing behavior of micropores in powder metallurgy （P/M） 316L stainless steel during hot forging and subsequent heat treatment was studied. The results showed that hot forging can improve the homogeneity of the...The healing behavior of micropores in powder metallurgy （P/M） 316L stainless steel during hot forging and subsequent heat treatment was studied. The results showed that hot forging can improve the homogeneity of the pore size and enhance the relative density of material in varying degree due to different forging temperatures. As a re- sult of deformation and diffusion bonding at high temperature, the irregular pores were spheroidized and finally turned into stable inner grain pores. The comparison of compression behavior between P/M and wrought dense mate rials has shown that the pores can either be the obstacles of dislocation movement or be the nucleation sites accelera- ting the reerystallization according to the difference of deformation temperatures.展开更多
Three-dimensional(3D)bioprinting provides a rapid and efficient method for fabricating customized bioprinted tissues that replicate the complex architecture of native tissues.However,in 3D bioprinting,the need for den...Three-dimensional(3D)bioprinting provides a rapid and efficient method for fabricating customized bioprinted tissues that replicate the complex architecture of native tissues.However,in 3D bioprinting,the need for dense biomaterial networks to ensure mechanical strength and structural fidelity often restricts the spreading,migration,and proliferation of encapsulated cells,as well as the transport of materials.This review summarizes effective strategies for manufacturing microporous bioprinted tissues via 3D bioprinting.The term“microporous”refers to interconnected,micrometer-sized pore-like structures within the internal materials of bioprinted tissues,including the microstructure of a single extruded fiber in extrusion printing.This differs from the macroscopic pore structure formed between fibers composed of print tracks or computer-aided design presets.These micropores play a crucial role in advancing biomanufacturing and 3D bioprinting by providing space for cell adhesion and proliferation while facilitating the timely transport of nutrients and metabolic waste essential for cell growth.Additionally,microporous bioprinted tissues offer the mechanical support needed for cell seeding and serve as sites for extracellular matrix deposition.As microporous 3D bioprinting continues to advance,it has the potential to address unresolved challenges in fields such as organ transplantation,tissue regeneration,and tissue replacement.展开更多
Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and exp...Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and expensive reagents used,the cost of SACs is usually too high to put into practical application.The development of cost-effective and sustainable SACs remains a great challenge.Herein,a low-cost method employing biomass is designed to prepare efficient single-atom Fe-N-C catalysts(SA-Fe-N-C).Benefiting from the confinement effect of porous carbon support and the coordination effect of glucose,SA-Fe-N-C is derived from cheap flour by the two-step pyrolysis.Atomically dispersed Fe atoms exist in the form of Fe-N_(x),which acts as active sites for ORR.The catalyst shows outstanding activity with a half-wave potential(E_(1/2))of 0.86 V,which is better than that of Pt/C(0.84 V).Additionally,the catalyst also exhibits superior stability.The ORR catalyzed by SA-Fe-N-C proceeds via an efficient 4e transfer pathway.The high performance of SA-Fe-N-C also benefits from its porous structure,extremely high specific surface area(1450.1 m^(2)/g),and abundant micropores,which are conducive to increasing the density of active sites and fully exposing them.This work provides a cost-effective strategy to synthesize SACs from cheap biomass,achieving a balance between performance and cost.展开更多
The construction of monodisperse microporous organic microspheres is deemed a challenging issue,primarily due to the difficulty in achieving both high microporosity and uniformity within the microspheres.In this study...The construction of monodisperse microporous organic microspheres is deemed a challenging issue,primarily due to the difficulty in achieving both high microporosity and uniformity within the microspheres.In this study,a series of fluorinated monodisperse microporous microspheres are fabricated by solvothermal precipitation polymerization.The resulting fluorous methacrylate-based microspheres achieved higher than 400 m^(2)/g surface area,along with a yield of over 90%for the microspheres.Through comprehensive characterization and simulation methods,we discovered that the introduction of fluorous methacrylate monomers at high loading levels is the key factor contributing to the formation of the microporosity within the microspheres.The controlled temperature profile was found to be advantageous for achieving a high yield of microspheres and increased uniformity.Two-dimensional assemblies of these fluorinated microsphere arrays exhibited superhydrophobicity,superolephilicity,and water sliding angles below 10°.Furthermore,a three-dimensional assembly of the fluorinated microporous microsphere in a chromatographic column demonstrated significant improvement in the separation of Engelhardt agent compared to commercial columns.Our work offers a novel approach to constructing fluorinated monodisperse microporous microspheres for advanced applications.展开更多
With the pressing concern of the climate change,hydrogen will undoubtedly play an essential role in the future to accelerate the way out from fossil fuel-based economy.In this case,the role of membrane-based separatio...With the pressing concern of the climate change,hydrogen will undoubtedly play an essential role in the future to accelerate the way out from fossil fuel-based economy.In this case,the role of membrane-based separation cannot be neglected since,compared with other conventional process,membrane-based process is more effective and consumes less energy.Regarding this,metal-based membranes,particularly palladium,are usually employed for hydrogen separation because of its high selectivity.However,with the advancement of various microporous materials,the status quo of the metal-based membranes could be challenged since,compared with the metal-based membranes,they could offer better hydrogen separation performance and could also be cheaper to be produced.In this article,the advancement of membranes fabricated from five main microporous materials,namely silica-based membranes,zeolite membranes,carbon-based membranes,metal organic frameworks/covalent organic frameworks(MOF/COF)membranes and microporous polymeric membranes,for hydrogen separation from light gases are extensively discussed.Their performances are then summarized to give further insights regarding the pathway that should be taken to direct the research direction in the future.展开更多
Exploration of efficient and stable photocatalysts to mimic natural leaves for the conversion of atmospheric CO_(2)into hydrocarbons utilizing solar light is very important but remains a major challenge.Herein,we repo...Exploration of efficient and stable photocatalysts to mimic natural leaves for the conversion of atmospheric CO_(2)into hydrocarbons utilizing solar light is very important but remains a major challenge.Herein,we report the design of four novel metal-salen-incorporated conjugated microporous polymers as robust artificial leaves for photoreduction of atmospheric CO_(2)with gaseous water.Owing to the rich nitrogen and oxygen moieties in the polymeric frameworks,they show a maximum CO_(2)adsorption capacity of 46.1 cm3 g^(−1)and adsorption selectivity for CO_(2)/N_(2)of up to 82 at 273 K.Under air atmosphere and simulated solar light(100mWcm^(−2)),TEPT-Zn shows an excellent CO yield of 304.96μmol h^(−1)g^(−1)with a selectivity of approximately 100%,which represents one of the best results in terms of organic photocatalysts for gas-phase CO_(2)photoreduction so far.Furthermore,only small degradation in the CO yield is observed even after 120-h continuous illumination.More importantly,a good CO yield of 152.52μmol g^(−1)was achieved by directly exposing the photocatalytic reaction of TEPT-Zn in an outdoor environment for 3 h(25-28℃,52.3±7.9mWcm^(−2)).This work provides an avenue for the continued development of advanced polymers toward gas-phase photoconversion of CO_(2)from air.展开更多
Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhan...Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhancing patient safety and meeting global dialysis water quality standards. Advanced filtration technologies, such as titanium dioxide (TiO₂)-based nanoparticle filters, offer a promising approach to improve water purification processes in renal care. Objectives: This study aimed to develop and evaluate the effectiveness of a TiO₂-based nanoparticle microporous filtration system for hemodialysis water purification. The objectives included analyzing the system’s performance in reducing chemical contaminants (calcium, magnesium, aluminum, and lead) and microbiological contaminants (total viable count [TVC] and endotoxin units [EU]) across multiple renal centers. Methods: Water samples from three renal centers (RC1, RC2, and RC3) were analyzed pre- and post-filtration. TiO₂ nanoparticles were synthesized using the sol-gel method and characterized via Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy with Energy Dispersive X-ray analysis (SEM/EDX). The microporous filter, fabricated with TiO₂ nanoparticles, silicon dioxide, and polyethylene glycol (PEG), was tested for its ability to remove contaminants. Analytical techniques included spectroscopy for chemical analysis and microbiological assays for contaminant quantification. Results: Post-treatment analysis revealed significant reductions in chemical contaminants, with removal efficiencies averaging 78% for calcium, 80% for magnesium, 81% for aluminum, and 76.6% for lead across all centers. Microbiological contamination was also substantially reduced, with 78–80% removal of TVC and 76–84.6% reduction in EU levels. FTIR analysis confirmed the presence of hydroxyl groups critical for adsorption, while SEM/EDX characterization revealed a crystalline structure with a particle size of 1.45 nm, pore size of 4.11 μm, filter height of 2.56 mm, and bulk density of 0.58 g/cm³. Conclusion: The TiO₂-based nanoparticle filtration system demonstrated high efficacy in removing chemical and microbiological contaminants, significantly improving water quality for hemodialysis. These results highlight its potential as a practical solution for renal centers, especially in resource-constrained settings. Further studies are needed to evaluate its long-term performance and feasibility for widespread adoption. Recommendation: Renal centers should consider adopting TiO2-based nanoparticle filters to address persistent water quality challenges. Pilot implementations across diverse settings can provide insights into operational feasibility. Additional research should explore scalability, maintenance requirements, and cost-effectiveness to optimize integration into healthcare systems. Significance Statement: This study introduces a practical and innovative solution to improve hemodialysis water purification. By effectively reducing both chemical and microbiological contaminants, the TiO2-based filtration system has the potential to enhance patient safety and outcomes, particularly in settings where maintaining high water quality standards remains challenging.展开更多
Homogeneous films with tailored microporous structures are crucial for several applications;however,fabricating such films presents significant challenges.This is primarily because most microporous materials have crys...Homogeneous films with tailored microporous structures are crucial for several applications;however,fabricating such films presents significant challenges.This is primarily because most microporous materials have crystal sizes in the nanoand micrometer ranges,which inevitably generates intergranular spaces in the films,thereby complicating the fabrication of these thin films.In this study,functionalized metal–organic polyhedra(MOPs)are used as discrete microporous units and assembled into homogenous microporous films.The generation of intergranular spaces is avoided while controlling packing parameters and film thicknesses.Initially,the MOP units,influenced by van der Waals forces between carbon chains of functionalized adipic acids,display an affinity to form spindle-shaped blocks and islands.As the MOP concentration increases,these structures self-assembled into a hexagonally packed structure with an in-plane orientation and a maximum stacking of two layers of MOPs.By contrast,un-functionalized MOPs form a disordered film structure owing to random agglomeration.Evidently,functionalized adipic acid influences the orientation of the MOP network films with uniformly distributed micropores,effectively preventing the formation of intergranular spaces.Additionally,formaldehyde adsorption and desorption experiments revealed that the MOP network films possess superior adsorption and desorption capacities.The proposed approach signifies a breakthrough in the fabrication of homogenous microporous films.展开更多
Flexible microporous metal rubber(FMP-MR)is widely used in national defense applications,yet its mechanical behavior under high-speed impact conditions remains insufficiently explored.In this study,dynamic and static ...Flexible microporous metal rubber(FMP-MR)is widely used in national defense applications,yet its mechanical behavior under high-speed impact conditions remains insufficiently explored.In this study,dynamic and static experiments were conducted to systematically investigate the mechanical response of metal-wrapped microporous materials under impact loading that spanned 10~6 orders of magnitude.By combining a high-precision numerical model with a spatial contact point search algorithm,the spatio–temporal contact characteristics of the complex network structure in FMP-MR were systematically analyzed.Furthermore,the mapping mechanism from turn topology and mesoscopic friction behavior to macroscopic mechanical properties was comprehensively explored.The results showed that compared with quasi-static loading,FMP-MR under high-speed impact exhibited higher energy absorption efficiency due to high-strain-rate inertia effect.Therefore,the peak stress increased by 141%,and the maximum energy dissipation increased by 300%.Consequently,the theory of dynamic friction locking effect was innovatively proposed.The theory explains that the close synergistic effect of sliding friction and plastic dissipation promoted by the stable interturn-locked embedded structure is the essential reason for the excellent dynamic mechanical properties of FMP-MR under dynamic loading conditions.Briefly,based on the in-depth investigation of the mechanical response and energy dissipation mechanism of FMP-MR under impact loads,this study provides a solid theoretical basis for further expanding the application range of FMP-MR and optimizing its performance.展开更多
Traditional magnesia-based refractories face challenges such as high thermal conductivity and poor slag penetration resistance,which contradict the energy efficiency requirements of modern metallurgy.In this study,mic...Traditional magnesia-based refractories face challenges such as high thermal conductivity and poor slag penetration resistance,which contradict the energy efficiency requirements of modern metallurgy.In this study,microporous magnesia was prepared using low-grade magnesite via the one-step sintering method.The microstructure and properties of microporous magnesia prepared by high-silicon and high-calcium magnesites calcined at various temperatures were compared.The pore structure and phase evolution were analyzed,the effect of which on the properties of lightweight magnesia-based dry vibration mix was discussed.The results indicated that within high-silicon magnesite,SiO_(2) initially reacted with Mgo to form Mg_(2)Si0_(4),which gradually reacted with Cao impurities as the temperature increased transforming into a Mgo-Cao-SiO_(2) ternary liquid phase and uniformly permeated along the grain boundaries.Due to the bridging effect of strip-like Cao in high-calcium magnesite,the reorganization and sintering of Mgo grains at high temperatures were inhibited,resulting in the presence of a significant number of elongated pores within the magnesia after calcination at various temperatures,which was detrimental to the mechanical properties and slag resistance.The microporous Mg0 prepared by high-silicon magnesite at 1700°C exhibited the superior physical properties.The microporous Mgo aggregates had a stronger interlocking force with the matrix,resulting in a greater bonding strength.Moreover,the micropores not only effectively reduced the thermal conductivity but also facilitated the supersaturated precipitation of molten slag,hindering further penetration.Compared to the dry vibration mix prepared by fused Mgo,the lightweight magnesia-based dry vibration mix prepared with the high-silicon magnesite exhibited higher mechanical strength(~40%increase)and thermal insulation performance(0.870 W·(m·K)at 1000 C),and improved slag resistance.展开更多
Microporous organic networks(MONs)are attractive adsorbents for use in sample pretreatment owning to their unique structure and properties.However,methods for constructing functional MONs are still limited because the...Microporous organic networks(MONs)are attractive adsorbents for use in sample pretreatment owning to their unique structure and properties.However,methods for constructing functional MONs are still limited because the lack of monomers via direct synthesis and their complex procedures via postmodification.To address this issue,a facile one-pot in situ doping strategy was proposed herein for synthesis a novel phenylboronic acid-functionalized magnetic cyclodextrin-based microporous organic network([PBA]_(3/4)-MCD-MON-0.04).[PBA]_(3/4)MCD-MON-0.04 was used for the selective and efficient extraction of sulfonylurea herbicides(SUHs)from complex food and environmental water samples via the synergistic hydrogen bonding,host-vip,hydrophobic andπ-πinteractions and the specific B-N coordination.[PBA]_(3/4)-MCD-MON-0.04 had a large surface area,high saturation magnetism,good reusability,and remarkable stability.A rapid,sensitive,and selective method was proposed for monitoring SUHs from diverse matrices.This study provides a new strategy for synthesizing novel and multifunctional magnetic CD-MONs-based adsorbents and reveals the considerable potential of CD-MONs in sample pretreatment.展开更多
Aqueous zinc-ion batteries(AZIBs)have hugely latent advantages in large-scale energy storage due to its innate safety,reasonable price,and sustainability.However,most AZIB cathode materials suffer from short cycling l...Aqueous zinc-ion batteries(AZIBs)have hugely latent advantages in large-scale energy storage due to its innate safety,reasonable price,and sustainability.However,most AZIB cathode materials suffer from short cycling life and poor rate performance.Herein,a bipolar donor-acceptor(D-A)conjugated microporous polymer(PTZ-BDTB),consisting of electron-withdrawing benzo[1,2-b:4,5-b']dithiophene-4,8-dio ne(BDTB)units and electron-donating phenothiazine(PTZ)units,is developed as the cathode material of aqueous zinc dual-ion batteries(AZDIBs).The D-A type structure design could reduce the band gap,thus promoting electron transfer in the polymer framework.Therefore,the PTZ-BDTB cathode in a30 mol/kg(m)ZnCl_(2)water-in-salt electrolyte exhibits a high reversible capacity of 202 mA h g^(-1)at0.05 A g^(-1)with excellent rate performance(109 mA h g^(-1)at 15 A g^(-1)),which is far superior to its counterpart polymers PPTZ and PB-BDTB.Impressively,PTZ-BDTB shows ultra-stable cycle performance with capacity retention ratios of 76.2%after 460 cycles at 0.05 A g^(-1)and 96%after 27000 cycles at 5 A g^(-1).PTZBDTB also exhibits a low self-discharge ability with capacity retention about 76.4%after resting the battery for 28 days.These results demonstrate that D-A type structural design is a promising strategy for constructing high performance cathode materials for AZDIBs.展开更多
Microporous MgO–MgAl_(2)O_(4)refractory aggregates were prepared using calcined MgO powder andα-Al_(2)O_(3)micro-powder as raw materials.The influence ofα-Al_(2)O_(3)micro-powder addition on the microstructures and...Microporous MgO–MgAl_(2)O_(4)refractory aggregates were prepared using calcined MgO powder andα-Al_(2)O_(3)micro-powder as raw materials.The influence ofα-Al_(2)O_(3)micro-powder addition on the microstructures and properties of the aggregates was investigated.The results indicated that the addition ofα-Al_(2)O_(3)micro-powder to MgO powder not only promoted more pores in the MgO powder to being enclosed,but also caused the pores among the MgO powder to become micronano scale by the formation of continuous microporous MgAl_(2)O_(4)bonding layers,which reduced the thermal conductivity of the aggregates.Furthermore,the microporous MgAl_(2)O_(4)can induce crack deflection and generate crack branching when subjected to thermal shock,thus improving the thermal shock resistance of the microporous aggregates.The sample with 12.1 wt.%α-Al_(2)O_(3)micro-powder addition exhibited the best comprehensive properties,with a bulk density of 3.44 g/cm^(3),a median pore size of 120.7 nm,a high flexural strength of 82.7 MPa,a high retention rate of flexural strength of 87.7%,and a thermal conductivity of 8.4 W/(m K)at 800°C.Compared to commercial fused magnesia and sintered magnesia,the thermal conductivity decreased by 47.2%and 18.4%at 800°C,respectively.展开更多
基金supported by the National Natural Science Foundation of China(22278155,U23A6005)。
文摘Lignin-derived hard carbon shows potential as an anode material for sodium-ion batteries(SIBs)due to its high carbon content and aromatic structure,but its limited reversible adsorption sites and low conductivity hinder performance.This study introduces a self-activation strategy to optimize carbon layer stacking and surface functional groups in microporous carbon,significantly enhancing sodium storage capacity and rate performance.By utilizing oxygen-containing functional groups in organic solvent lignin,we induce micropore formation during pyrolysis,effectively regulating graphite domains and closed pores structures without disrupting carbon layer growth.Unstacked graphene layers serve as efficient electron transport channels and expose additional adsorption sites,simultaneously increasing sodium storage capacity and intrinsic conductivity.The resultant S-OLHC demonstrates a remarkable sodium storage capacity of 358 mA h/g at 0.05 A/g after 200 cycles and maintains 231 mA h/g after 1000 cycles at 2 A/g.This strategy eliminates the need for additional pore-forming agents,offering a simpler,more efficient,and environmentally friendly approach compared to traditional activation methods.This work advances the rational design of high-performance biomass-derived hard carbon for SIBs by leveraging inherent structural characteristics and provides a sustainable low-carbon strategy for lignin valorization in renewable energy storage.
基金The National Natural Science Foundation of China(No.51578137).
文摘To accurately analyze the impact of casting pores in steel,high-resolution 3D X-ray tomography technology was used to gather detailed statistical information about micropores.These micropores were classified as gas,shrinkage,and gas-shrinkage pores depending on their formation origin and morphology.Clustering tendencies and affinity parameters were defined to characterize the spatial correlations among these three types of pores.The 3D data from X-ray tomography scans were then integrated into finite element analysis(FEA)software to predict how micropore shape,size,and distribution influence stress distribution within the material.The results show that certain inflection points with small local radii within the cast pores are major contributors to stress concentration.Therefore,cast pores cannot be simply modeled as ideal spherical pores.The sphericity and volume of pores have a significant impact on the stress concentration of the model.Specifically,lower sphericity and larger pore volumes result in higher stress concentrations.Moreover,the internal pores of steel castings exhibit specific global distribution characteristics.Pores located on the surface of the specimen lead to significantly higher stress concentrations compared to those located inside the specimen.
文摘In this work, four empirical models of statistical thickness, namely the models of Harkins and Jura, Hasley, Carbon Black and Jaroniec, were compared in order to determine the textural properties (external surface and surface of micropores) of a clay concrete without molasses and clay concretes stabilized with 8%, 12% and 16% molasses. The results obtained show that Hasley’s model can be used to obtain the external surfaces. However, it does not allow the surface of the micropores to be obtained, and is not suitable for the case of simple clay concrete (without molasses) and for clay concretes stabilized with molasses. The Carbon Black, Jaroniec and Harkins and Jura models can be used for clay concrete and stabilized clay concrete. However, the Carbon Black model is the most relevant for clay concrete and the Harkins and Jura model is for molasses-stabilized clay concrete. These last two models augur well for future research.
基金financially supported by the National Natural Science Foundation of China (grant No. 41702171)a National Science and Technology Major Project (grant No. 2016ZX05034002)
文摘Micropores of shale are significant to the gas content and production potential of shale, which has been verified in the research of marine shale gas; while, few studies have been conducted on lacustrine shales. This study collected 42 samples from three wells in the Late Cretaceous Qingshankou Formation of the southern Songliao Basin, NE China, and investigated these samples by the focused ion beam-scanning electron microscope(FIB–SEM) and nitrogen adsorption analysis techniques. Four types of micropores were identified in the samples, i.e., intergranular pore, intracellular pore, organic matter pore and microfracture. The pore structure type is characterized by open slit pores and "ink type" pores which are mainly 1.5–5 nm in diameter with mesopores as the main pores. The mesopores account for 74.01% of the pore volume and 54.68% of the pore surface area. Compared with the lacustrine shales from the Triassic Yanchang Formation in the Ordos Basin and Xujiahe Formation in the Sichuan Basin, the intergranular clay mineral interlayer pores are considered to be the main reservoir space for shale gas storage in the study area, followed by intraparticle pores, organic matter pores and microfractures. Maturity and micropore are the key controlling factors which affect the shale gas content of the Qingshankou Formation in southern Songliao Basin.
基金financially supported by the National Key R&D Program of China (No. 2018YFB0104000 and No. 2019YFA0210300)National Nature Science Foundation of China (No.21571189 and No.21671200)+3 种基金Natural Science Foundation of Jiangsu Province (BK20200991)Hunan Provincial Science and Technology Plan Project of China (No. 2019GK2033, No. 2017TP1001, CPS2019K06 and No. 2018RS3009)Postdoctoral International Exchange Program Funding of China (No. [2018]115)China Postdoctoral Science Foundation (2019M652802)
文摘Energy conversion technologies like fuel cells and metal-air batteries require oxygen reduction reaction(ORR)electrocatalysts with low cost and high catalytic activity.Herein,N-doped carbon spheres(N-CS)with rich micropore structure have been synthesized by a facile two-step method,which includes the polymerization of pyrrole and formaldehyde and followed by a facile pyrolysis process.During the preparation,zinc chloride(ZnCl2)was utilized as a catalyst to promote polymerization and provide a hypersaline environment.In addition,the morphology,defect content and activity area of the resultant N-CS catalysts could be regulated by controlling the content of ZnCl2.The optimum N-CS-1 catalyst demonstrated much better catalytic activity and durability towards ORR in alkaline conditions than commercial 20 wt%Pt/C catalysts,of which the half-wave potential reached 0.844 V vs.RHE.When applied in the Zn-air batteries as cathode catalysts,N-CS-1 showed a maximum power density of 175 mW cm^(-2) and long-term discharging stability of over 150 h at 10 mA cm^(-2),which outperformed 20 wt%Pt/C.The excellent performance could be due to its ultrahigh specific surface area of 1757 m2 g1 and rich micropore channels structure.Meanwhile,this work provides an efficient method to synthesize an ultrahigh surface porous carbon material,especially for catalyst application.
基金supported by the National Natural Science Foundation of China (Grant No 10674066)State Key Laboratory of Acoustics (Grant No 200802)
文摘Based on an equivalent medium approach, this paper presents a model describing the nonlinear propagation of acoustic waves in a viscoelastic medium containing cylindrical micropores. The influences of pores＇ nonlinear oscillations on sound attenuation, sound dispersion and an equivalent acoustic nonlinearity parameter are discussed. The calculated results show that the attenuation increases with an increasing volume fraction of micropores. The peak of sound velocity and attenuation occurs at the resonant frequency of the micropores while the peak of the equivalent acoustic nonlinearity parameter occurs at the half of the resonant frequency of the micropores. Furthermore, multiple scattering has been taken into account, which leads to a modification to the effective wave number in the equivalent medium approach. We find that these linear and nonlinear acoustic parameters need to be corrected when the volume fraction of micropores is larger than 0.1%.
基金financially supported by the National Natural Science Foundation of China(No.52273267)the Fundamental Research Funds for the Central Universities(Nos.30920041102 and 30920021107)。
文摘Conjugated microporous polymers have excellent skeleton structures but poor electrical conductivity limits their applications in microwave absorption.To solve this problem,a strategy of molecular expansion and confining polymerization is proposed in this work to synthesize conductive hyper-crosslinked conjugated microporous polymer.The topology of the conjugated microporous polymer is changed into a three-dimensional skeleton structure with high specific surface area by using molecular expansion technique,and the controlled growth of polypyrrole in the channel constructs a unique network structure.The balance of excellent composite backbone structure,proper conductivity,attenuation capability and impedance matching enable the material to exhibit electromagnetic wave absorption performance.As a result,with low filler loading of 10 wt%,a strongest reflection loss of-52.68 d B and a maximum effective bandwidth of 5.76 GHz.Additionally,CST simulations of the radar scattering cross section have been carried out to verify the excellent material properties.This study provides new concepts for new conductive polymers and broadens the application of hyper-crosslinked conjugated microporous polymer in the field of electromagnetic wave absorption.
基金Item Sponsored by National Basic Research Program of China(2012CB619600)
文摘The healing behavior of micropores in powder metallurgy （P/M） 316L stainless steel during hot forging and subsequent heat treatment was studied. The results showed that hot forging can improve the homogeneity of the pore size and enhance the relative density of material in varying degree due to different forging temperatures. As a re- sult of deformation and diffusion bonding at high temperature, the irregular pores were spheroidized and finally turned into stable inner grain pores. The comparison of compression behavior between P/M and wrought dense mate rials has shown that the pores can either be the obstacles of dislocation movement or be the nucleation sites accelera- ting the reerystallization according to the difference of deformation temperatures.
基金supported by the National Natural Science Foundation of China(Nos.82302786 and 82172394)the China Postdoctoral Science Foundation(Nos.BX20230245 and 2023M742478)+4 种基金the Sichuan Science and Technology Program(No.2023YFH0068)the Sichuan Province Innovative Talent Funding Project for Postdoctoral Fellows(No.BX202203)the Sichuan University Postdoctoral Interdisciplinary Innovation Fund(No.JCXK2226)1·3·5 Project for Disciplines of Excellence,West China Hospital,Sichuan University(No.ZYGD23033)the Postdoctoral Research Fund of West China Hospital,Sichuan University(No.2023HXBH012).
文摘Three-dimensional(3D)bioprinting provides a rapid and efficient method for fabricating customized bioprinted tissues that replicate the complex architecture of native tissues.However,in 3D bioprinting,the need for dense biomaterial networks to ensure mechanical strength and structural fidelity often restricts the spreading,migration,and proliferation of encapsulated cells,as well as the transport of materials.This review summarizes effective strategies for manufacturing microporous bioprinted tissues via 3D bioprinting.The term“microporous”refers to interconnected,micrometer-sized pore-like structures within the internal materials of bioprinted tissues,including the microstructure of a single extruded fiber in extrusion printing.This differs from the macroscopic pore structure formed between fibers composed of print tracks or computer-aided design presets.These micropores play a crucial role in advancing biomanufacturing and 3D bioprinting by providing space for cell adhesion and proliferation while facilitating the timely transport of nutrients and metabolic waste essential for cell growth.Additionally,microporous bioprinted tissues offer the mechanical support needed for cell seeding and serve as sites for extracellular matrix deposition.As microporous 3D bioprinting continues to advance,it has the potential to address unresolved challenges in fields such as organ transplantation,tissue regeneration,and tissue replacement.
基金Project(52174338)supported by the National Natural Science Foundation of ChinaProjects(2022JJ20086,2021JJ30796)supported by the Natural Science Foundation of Hunan Province,China+1 种基金Project(2023CXQD005)supported by the Central South University Innovation-Driven Research Programme,ChinaProject(23B0841)supported by the Education Department of Hunan Provincial Government,China。
文摘Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and expensive reagents used,the cost of SACs is usually too high to put into practical application.The development of cost-effective and sustainable SACs remains a great challenge.Herein,a low-cost method employing biomass is designed to prepare efficient single-atom Fe-N-C catalysts(SA-Fe-N-C).Benefiting from the confinement effect of porous carbon support and the coordination effect of glucose,SA-Fe-N-C is derived from cheap flour by the two-step pyrolysis.Atomically dispersed Fe atoms exist in the form of Fe-N_(x),which acts as active sites for ORR.The catalyst shows outstanding activity with a half-wave potential(E_(1/2))of 0.86 V,which is better than that of Pt/C(0.84 V).Additionally,the catalyst also exhibits superior stability.The ORR catalyzed by SA-Fe-N-C proceeds via an efficient 4e transfer pathway.The high performance of SA-Fe-N-C also benefits from its porous structure,extremely high specific surface area(1450.1 m^(2)/g),and abundant micropores,which are conducive to increasing the density of active sites and fully exposing them.This work provides a cost-effective strategy to synthesize SACs from cheap biomass,achieving a balance between performance and cost.
基金supported by Natural Science Foundation of Shandong Province(No.ZR2022MB033)Science and Technology Bureau of Jinan City(No.2021GXRC105)University of Jinan Disciplinary Cross-Convergence Construction Project 2023(No.XKJC-202302)。
文摘The construction of monodisperse microporous organic microspheres is deemed a challenging issue,primarily due to the difficulty in achieving both high microporosity and uniformity within the microspheres.In this study,a series of fluorinated monodisperse microporous microspheres are fabricated by solvothermal precipitation polymerization.The resulting fluorous methacrylate-based microspheres achieved higher than 400 m^(2)/g surface area,along with a yield of over 90%for the microspheres.Through comprehensive characterization and simulation methods,we discovered that the introduction of fluorous methacrylate monomers at high loading levels is the key factor contributing to the formation of the microporosity within the microspheres.The controlled temperature profile was found to be advantageous for achieving a high yield of microspheres and increased uniformity.Two-dimensional assemblies of these fluorinated microsphere arrays exhibited superhydrophobicity,superolephilicity,and water sliding angles below 10°.Furthermore,a three-dimensional assembly of the fluorinated microporous microsphere in a chromatographic column demonstrated significant improvement in the separation of Engelhardt agent compared to commercial columns.Our work offers a novel approach to constructing fluorinated monodisperse microporous microspheres for advanced applications.
基金funding from the Alexander von Humboldt Postdoctoral Fellowship(Ref-3.3-GBR-1219268-HFST-P)。
文摘With the pressing concern of the climate change,hydrogen will undoubtedly play an essential role in the future to accelerate the way out from fossil fuel-based economy.In this case,the role of membrane-based separation cannot be neglected since,compared with other conventional process,membrane-based process is more effective and consumes less energy.Regarding this,metal-based membranes,particularly palladium,are usually employed for hydrogen separation because of its high selectivity.However,with the advancement of various microporous materials,the status quo of the metal-based membranes could be challenged since,compared with the metal-based membranes,they could offer better hydrogen separation performance and could also be cheaper to be produced.In this article,the advancement of membranes fabricated from five main microporous materials,namely silica-based membranes,zeolite membranes,carbon-based membranes,metal organic frameworks/covalent organic frameworks(MOF/COF)membranes and microporous polymeric membranes,for hydrogen separation from light gases are extensively discussed.Their performances are then summarized to give further insights regarding the pathway that should be taken to direct the research direction in the future.
基金Research Foundation for Advanced Talents of East China University of Technology,Grant/Award Number:DHBK201927Excellent Youth Foundation of Jiangxi Scientific Committee,Grant/Award Number:20232ACB213012+2 种基金National Science Foundation for Young Scientists of China,Grant/Award Number:21905122National Science Foundation for Young Scientists,Grant/Award Number:21905147Jiangxi Talent Program,Grant/Award Number:DHSQT32022005.
文摘Exploration of efficient and stable photocatalysts to mimic natural leaves for the conversion of atmospheric CO_(2)into hydrocarbons utilizing solar light is very important but remains a major challenge.Herein,we report the design of four novel metal-salen-incorporated conjugated microporous polymers as robust artificial leaves for photoreduction of atmospheric CO_(2)with gaseous water.Owing to the rich nitrogen and oxygen moieties in the polymeric frameworks,they show a maximum CO_(2)adsorption capacity of 46.1 cm3 g^(−1)and adsorption selectivity for CO_(2)/N_(2)of up to 82 at 273 K.Under air atmosphere and simulated solar light(100mWcm^(−2)),TEPT-Zn shows an excellent CO yield of 304.96μmol h^(−1)g^(−1)with a selectivity of approximately 100%,which represents one of the best results in terms of organic photocatalysts for gas-phase CO_(2)photoreduction so far.Furthermore,only small degradation in the CO yield is observed even after 120-h continuous illumination.More importantly,a good CO yield of 152.52μmol g^(−1)was achieved by directly exposing the photocatalytic reaction of TEPT-Zn in an outdoor environment for 3 h(25-28℃,52.3±7.9mWcm^(−2)).This work provides an avenue for the continued development of advanced polymers toward gas-phase photoconversion of CO_(2)from air.
文摘Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhancing patient safety and meeting global dialysis water quality standards. Advanced filtration technologies, such as titanium dioxide (TiO₂)-based nanoparticle filters, offer a promising approach to improve water purification processes in renal care. Objectives: This study aimed to develop and evaluate the effectiveness of a TiO₂-based nanoparticle microporous filtration system for hemodialysis water purification. The objectives included analyzing the system’s performance in reducing chemical contaminants (calcium, magnesium, aluminum, and lead) and microbiological contaminants (total viable count [TVC] and endotoxin units [EU]) across multiple renal centers. Methods: Water samples from three renal centers (RC1, RC2, and RC3) were analyzed pre- and post-filtration. TiO₂ nanoparticles were synthesized using the sol-gel method and characterized via Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy with Energy Dispersive X-ray analysis (SEM/EDX). The microporous filter, fabricated with TiO₂ nanoparticles, silicon dioxide, and polyethylene glycol (PEG), was tested for its ability to remove contaminants. Analytical techniques included spectroscopy for chemical analysis and microbiological assays for contaminant quantification. Results: Post-treatment analysis revealed significant reductions in chemical contaminants, with removal efficiencies averaging 78% for calcium, 80% for magnesium, 81% for aluminum, and 76.6% for lead across all centers. Microbiological contamination was also substantially reduced, with 78–80% removal of TVC and 76–84.6% reduction in EU levels. FTIR analysis confirmed the presence of hydroxyl groups critical for adsorption, while SEM/EDX characterization revealed a crystalline structure with a particle size of 1.45 nm, pore size of 4.11 μm, filter height of 2.56 mm, and bulk density of 0.58 g/cm³. Conclusion: The TiO₂-based nanoparticle filtration system demonstrated high efficacy in removing chemical and microbiological contaminants, significantly improving water quality for hemodialysis. These results highlight its potential as a practical solution for renal centers, especially in resource-constrained settings. Further studies are needed to evaluate its long-term performance and feasibility for widespread adoption. Recommendation: Renal centers should consider adopting TiO2-based nanoparticle filters to address persistent water quality challenges. Pilot implementations across diverse settings can provide insights into operational feasibility. Additional research should explore scalability, maintenance requirements, and cost-effectiveness to optimize integration into healthcare systems. Significance Statement: This study introduces a practical and innovative solution to improve hemodialysis water purification. By effectively reducing both chemical and microbiological contaminants, the TiO2-based filtration system has the potential to enhance patient safety and outcomes, particularly in settings where maintaining high water quality standards remains challenging.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean Government(MSIT)(Nos.NRF-2021R1C1C2012825,2022R1A2B5B01001826,2022R1A5A2021216,and No.RS-2023-00218255)。
文摘Homogeneous films with tailored microporous structures are crucial for several applications;however,fabricating such films presents significant challenges.This is primarily because most microporous materials have crystal sizes in the nanoand micrometer ranges,which inevitably generates intergranular spaces in the films,thereby complicating the fabrication of these thin films.In this study,functionalized metal–organic polyhedra(MOPs)are used as discrete microporous units and assembled into homogenous microporous films.The generation of intergranular spaces is avoided while controlling packing parameters and film thicknesses.Initially,the MOP units,influenced by van der Waals forces between carbon chains of functionalized adipic acids,display an affinity to form spindle-shaped blocks and islands.As the MOP concentration increases,these structures self-assembled into a hexagonally packed structure with an in-plane orientation and a maximum stacking of two layers of MOPs.By contrast,un-functionalized MOPs form a disordered film structure owing to random agglomeration.Evidently,functionalized adipic acid influences the orientation of the MOP network films with uniformly distributed micropores,effectively preventing the formation of intergranular spaces.Additionally,formaldehyde adsorption and desorption experiments revealed that the MOP network films possess superior adsorption and desorption capacities.The proposed approach signifies a breakthrough in the fabrication of homogenous microporous films.
基金National Natural Science Foundation of China-NSAF(Grant No.U2330202)the National Natural Science Foundation of China(Grant Nos.52175162 and 51805086)+1 种基金Fujian Provincial Technological Innovation Key Research and Industrialization Projects(Grant Nos.2023XQ005 and 2024XQ010)The National Independent Innovation Demonstration Platform Project of Fujian Province(2024QZFX07)。
文摘Flexible microporous metal rubber(FMP-MR)is widely used in national defense applications,yet its mechanical behavior under high-speed impact conditions remains insufficiently explored.In this study,dynamic and static experiments were conducted to systematically investigate the mechanical response of metal-wrapped microporous materials under impact loading that spanned 10~6 orders of magnitude.By combining a high-precision numerical model with a spatial contact point search algorithm,the spatio–temporal contact characteristics of the complex network structure in FMP-MR were systematically analyzed.Furthermore,the mapping mechanism from turn topology and mesoscopic friction behavior to macroscopic mechanical properties was comprehensively explored.The results showed that compared with quasi-static loading,FMP-MR under high-speed impact exhibited higher energy absorption efficiency due to high-strain-rate inertia effect.Therefore,the peak stress increased by 141%,and the maximum energy dissipation increased by 300%.Consequently,the theory of dynamic friction locking effect was innovatively proposed.The theory explains that the close synergistic effect of sliding friction and plastic dissipation promoted by the stable interturn-locked embedded structure is the essential reason for the excellent dynamic mechanical properties of FMP-MR under dynamic loading conditions.Briefly,based on the in-depth investigation of the mechanical response and energy dissipation mechanism of FMP-MR under impact loads,this study provides a solid theoretical basis for further expanding the application range of FMP-MR and optimizing its performance.
基金National Natural Science Foundation of China(52302027,52272022 and 52472032).
文摘Traditional magnesia-based refractories face challenges such as high thermal conductivity and poor slag penetration resistance,which contradict the energy efficiency requirements of modern metallurgy.In this study,microporous magnesia was prepared using low-grade magnesite via the one-step sintering method.The microstructure and properties of microporous magnesia prepared by high-silicon and high-calcium magnesites calcined at various temperatures were compared.The pore structure and phase evolution were analyzed,the effect of which on the properties of lightweight magnesia-based dry vibration mix was discussed.The results indicated that within high-silicon magnesite,SiO_(2) initially reacted with Mgo to form Mg_(2)Si0_(4),which gradually reacted with Cao impurities as the temperature increased transforming into a Mgo-Cao-SiO_(2) ternary liquid phase and uniformly permeated along the grain boundaries.Due to the bridging effect of strip-like Cao in high-calcium magnesite,the reorganization and sintering of Mgo grains at high temperatures were inhibited,resulting in the presence of a significant number of elongated pores within the magnesia after calcination at various temperatures,which was detrimental to the mechanical properties and slag resistance.The microporous Mg0 prepared by high-silicon magnesite at 1700°C exhibited the superior physical properties.The microporous Mgo aggregates had a stronger interlocking force with the matrix,resulting in a greater bonding strength.Moreover,the micropores not only effectively reduced the thermal conductivity but also facilitated the supersaturated precipitation of molten slag,hindering further penetration.Compared to the dry vibration mix prepared by fused Mgo,the lightweight magnesia-based dry vibration mix prepared with the high-silicon magnesite exhibited higher mechanical strength(~40%increase)and thermal insulation performance(0.870 W·(m·K)at 1000 C),and improved slag resistance.
基金supported by the National Natural Science Foundation of China(Nos.22174071 and 22206114)the Natural Science Foundation of Shandong Province(Nos.ZR2022YQ08 and ZR2022QB085)+2 种基金the Innovation Team of Shandong Higher School Youth Innovation Technology Program(No.2023KJ344)the Academic Promotion Program(No.2019LJ003)Joint Innovation Team for Clinical&Basic Research(No.202401)of Shandong First Medical University。
文摘Microporous organic networks(MONs)are attractive adsorbents for use in sample pretreatment owning to their unique structure and properties.However,methods for constructing functional MONs are still limited because the lack of monomers via direct synthesis and their complex procedures via postmodification.To address this issue,a facile one-pot in situ doping strategy was proposed herein for synthesis a novel phenylboronic acid-functionalized magnetic cyclodextrin-based microporous organic network([PBA]_(3/4)-MCD-MON-0.04).[PBA]_(3/4)MCD-MON-0.04 was used for the selective and efficient extraction of sulfonylurea herbicides(SUHs)from complex food and environmental water samples via the synergistic hydrogen bonding,host-vip,hydrophobic andπ-πinteractions and the specific B-N coordination.[PBA]_(3/4)-MCD-MON-0.04 had a large surface area,high saturation magnetism,good reusability,and remarkable stability.A rapid,sensitive,and selective method was proposed for monitoring SUHs from diverse matrices.This study provides a new strategy for synthesizing novel and multifunctional magnetic CD-MONs-based adsorbents and reveals the considerable potential of CD-MONs in sample pretreatment.
基金financial supported by the National Natural Science Foundation of China(22175110&22375076,52103264)the Hubei Provincial Natural Science Foundation of China(2024AFA031)the Key Research and Development Program of Wuhan(2024010802030157)。
文摘Aqueous zinc-ion batteries(AZIBs)have hugely latent advantages in large-scale energy storage due to its innate safety,reasonable price,and sustainability.However,most AZIB cathode materials suffer from short cycling life and poor rate performance.Herein,a bipolar donor-acceptor(D-A)conjugated microporous polymer(PTZ-BDTB),consisting of electron-withdrawing benzo[1,2-b:4,5-b']dithiophene-4,8-dio ne(BDTB)units and electron-donating phenothiazine(PTZ)units,is developed as the cathode material of aqueous zinc dual-ion batteries(AZDIBs).The D-A type structure design could reduce the band gap,thus promoting electron transfer in the polymer framework.Therefore,the PTZ-BDTB cathode in a30 mol/kg(m)ZnCl_(2)water-in-salt electrolyte exhibits a high reversible capacity of 202 mA h g^(-1)at0.05 A g^(-1)with excellent rate performance(109 mA h g^(-1)at 15 A g^(-1)),which is far superior to its counterpart polymers PPTZ and PB-BDTB.Impressively,PTZ-BDTB shows ultra-stable cycle performance with capacity retention ratios of 76.2%after 460 cycles at 0.05 A g^(-1)and 96%after 27000 cycles at 5 A g^(-1).PTZBDTB also exhibits a low self-discharge ability with capacity retention about 76.4%after resting the battery for 28 days.These results demonstrate that D-A type structural design is a promising strategy for constructing high performance cathode materials for AZDIBs.
基金financially supported by the Key Projects of the National Natural Science Foundation of China(No.U21A2058)the Innovation Group Project of Natural Science Foundation of Hubei Province(2025AFA016).
文摘Microporous MgO–MgAl_(2)O_(4)refractory aggregates were prepared using calcined MgO powder andα-Al_(2)O_(3)micro-powder as raw materials.The influence ofα-Al_(2)O_(3)micro-powder addition on the microstructures and properties of the aggregates was investigated.The results indicated that the addition ofα-Al_(2)O_(3)micro-powder to MgO powder not only promoted more pores in the MgO powder to being enclosed,but also caused the pores among the MgO powder to become micronano scale by the formation of continuous microporous MgAl_(2)O_(4)bonding layers,which reduced the thermal conductivity of the aggregates.Furthermore,the microporous MgAl_(2)O_(4)can induce crack deflection and generate crack branching when subjected to thermal shock,thus improving the thermal shock resistance of the microporous aggregates.The sample with 12.1 wt.%α-Al_(2)O_(3)micro-powder addition exhibited the best comprehensive properties,with a bulk density of 3.44 g/cm^(3),a median pore size of 120.7 nm,a high flexural strength of 82.7 MPa,a high retention rate of flexural strength of 87.7%,and a thermal conductivity of 8.4 W/(m K)at 800°C.Compared to commercial fused magnesia and sintered magnesia,the thermal conductivity decreased by 47.2%and 18.4%at 800°C,respectively.
