Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates sign...Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates significantly at elevated temperatures exceeding 600℃,primarily due to the collapse of pore structure.Meanwhile,the shielding capacity of SiO_(2) aerogel to the infrared radiation at high temperature is rather low due to the intrinsic properties of SiO_(2).Herein,a strategy for improving the high-temperature stability and infrared shielding properties of SiO_(2) aerogel via Ca doping was explored.Calcium-doped silica aerogel(CSA)powders were prepared by Sol-Gel,hydrothermal,and ambient pressure drying(APD)techniques using water glass and anhydrous calcium chloride as precursors and trimethylchlorosilane as a hydrophobic modifier.The effects of Ca/Si molar ratio in the precursor and hydrothermal conditions(temperature and pH)on the crystalline properties,microscopic morphology and pore structure of CSAs were investigated.The results show that the Ca/Si molar ratio and hydrothermal treatment have significant effects on the microstructure and heat resistance of CSAs in the temperature range of 400-1000℃.The samples sintered at 1000℃have a high specific surface area of 100.1 m^(2)/g and a pore volume of 0.8705 cm^(3)/g,indicating that the CSA has good heat resistance.One-side insulation tests at temperatures up to 600℃show that the sample with a Ca/Si molar ratio of 1.0 has the best insulation performance,with a cold surface temperature of 450℃,which is 27℃lower than that of the pure silica aerogel.展开更多
Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms lig...Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms ligand bonds or hydrogen bonds with sulfur ions in lithium polysulfides(LiPSs),thus inhibiting the shuttle effect.Electrochemical analyses demonstrated that lithium‑sulfur(Li‑S)batteries employing the NH2‑SS interlayer exhibited discharge specific capacities of 1048 and 789 mAh·g^(-1) at 0.2C and 2C,respectively,and even at 4C,the initial discharge specific capacity remained at 590 mAh·g^(-1),outperforming the Li‑S battery with unmodified SS as the interlayer.展开更多
The transport properties of liquid mixtures confined within porous media can change significantly from those observed for bulk mixtures due to changes in the liquid structuring within the pore space.Here,pulsed field ...The transport properties of liquid mixtures confined within porous media can change significantly from those observed for bulk mixtures due to changes in the liquid structuring within the pore space.Here,pulsed field gradient NMR was used to measure the diffusion coefficient of ethanol in ethanol-water liquid mixtures confined within silicas with pore diameters of 6 nm and 3 nm as a function of composition.For liquids imbibed within the 6 nm pores,the composition dependence of the ethanol diffusion coefficient closely followed that of the bulk liquid mixture and the absolute diffusion coefficients were reduced by a tortuosity factor of 3,with a minor contribution due to liquid-surface interactions.For liquids imbibed within the 3 nm pores,the diffusion coefficient of ethanol decreased as the composition of ethanol within the pore space increased,and for single-component ethanol imbibition the effective tortuosity was 63.Fast field cycling NMR experiments showed that the diffusion behaviour was not controlled by an increase in ethanol adsorption strength.A geometric analysis of the pore space was consistent with a highly confined system in which most molecules interacted with the pore walls.Under such confinement,the liquid structuring within the bulk pore space did not reflect that of the bulk liquid mixtures,and the observed decrease in diffusion coefficient as ethanol composition increased was consistent with an increase in confinement due to the larger size of the ethanol molecule.展开更多
Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through...Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through covalent bonds exhibits excellent structural stability.It has been shown that the stationary phases prepared by combining MOF and COF can make up for the poor stability of MOF@SiO_(2),and the MOF/COF composites have superior chromatographic separation performance.However,the traditional methods for preparing COF/MOF based stationary phases are generally solvent thermal synthesis.In this study,a green and low-cost synthesis method was proposed for the preparation of MOF/COF@SiO_(2) stationary phase.Firstly,COF@SiO_(2) was prepared in a choline chloride/ethylene glycol based deep eutectic solvent(DES).Secondly,another acid-base tunable DES prepared by mixing p-toluenesulfonic acid(PTSA)and 2-methylimidazole in different proportions was introduced as the reaction solvent and reactant for rapid synthesis of MOF/COF@SiO_(2).Compared with the toxic transition metal-based MOFs selected in most previous studies,a lightweight and non-toxic S-zone metal(calcium) based MOF was employed in this study.PTSA and calcium will form the calcium/oxygen-containing organic acid framework in acidic DES,which assembles with terephthalic acid dissolved in basic DES to form MOF.The strong hydrogen bonding effect of DES can facilitate rapid assembly of Ca-MOF.The obtained Ca-MOF/COF@SiO_(2) can be used for multi-mode chromatography to efficiently separate multiple isomeric/hydrophilic/hydrophobic analytes.The synthesis method of Ca-MOF/COF@SiO_(2) is green and mild,especially the use of acid-base tunable DES promotes the rapid synthesis of non-toxic Ca-MOF/COF@silica composites,which offers an innovative approach of greenly synthesizing novel MOF/COF stationary phases and extends their applications in the field of chromatography.展开更多
Treating bone defects complicated by bacterial infections remains a significant clinical challenge.Drawing inspiration from the human body's bone repair mechanisms,the use of biomimetic methods to design tissue en...Treating bone defects complicated by bacterial infections remains a significant clinical challenge.Drawing inspiration from the human body's bone repair mechanisms,the use of biomimetic methods to design tissue engineering scaffolds is of great significance for bone repair.This study synthesized copper(Cu)-doped mesoporous silica nanoparticles(Cu@MSN)modified with hydroxyethyl methacrylate to obtain methacrylated Cu@MSN(Cu@MSNMA).Furtheremore,bio-mimetic nanocomposite hydrogels were prepared by adding Cu@MSNMA to a GelMA/gelatin solution.This hydrogel achieves multi-modal bone tissue biomimicry:(ⅰ)GelMA/gelatin mimics the matrix components in bone ECM,ensuring biocompatibility while promoting cellular behavior(such as adhesion,proliferation,and differentiation);(ⅱ)GelMA/gela-tin and the crosslinking sites introduced by Cu@MSNMA form a stable porous network structure,achieving structural and mechanical biomimicry to provide necessary support for bone defects;(ⅲ)The elemental biomimicry of Si and Cu in Cu@MSNMA achieves efficient osteogenic induction.The effect of different proportions of Cu@MSNMA on the physi-cal properties of the composite hydrogels was investigated to determine the optimal proportion.The results indicated that the mechanical properties of hydrogel were enhanced with the increasing Cu@MSNMA mass ratio.Notably,5%NPs/GelMA/gelatin hydrogel exhibited excellent mechanical property compared to the GelMA/gelatin hydrogel.In vitro and vivo cellular experiments demonstrated a significant enhancement in antibacterial and osteogenic induction with Cu@MSNMA addition.In conclusion,the proposed nanocomposite hydrogel with biomimetic components and ion-regulating properties can serve as a multifunctional scaffold,offering antimicrobial properties for infected bone regeneration,and guide for future research in bone regeneration and three-dimensional printing.展开更多
Silica fibers were modified by a specific ratio of SiB6 mixed with silica sol through vacuum impregnation method.The modified fibers were then incorporated into a phenolic resin matrix to prepare fiber-reinforced resi...Silica fibers were modified by a specific ratio of SiB6 mixed with silica sol through vacuum impregnation method.The modified fibers were then incorporated into a phenolic resin matrix to prepare fiber-reinforced resin composites.The influences of the SiB_(6)/SiO_(2)mixed modification on silica fiber properties were analyzed through thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),scanning electron microscopy(SEM),and X-ray diffraction(XRD),respectively.Additionally,the influence of the SiB_(6)/SiO_(2)mixed modification on the mechanical properties of phenolic resin matrix composites was evaluated through mechanical testing.The experimeatal results indicate that the SiB_(6)/SiO_(2)mixed surface modification shows significant improvement in strength at room temperature and high temperatures,and crystallization temperature of silica fiber increases.The SiB_(6)/Silica sol co-modified silica fiber shows potential for future application in thermal protection and other high-temperature conditions.展开更多
According the importance of the stored grains and other products,it is an essential to keep them from khapra beetle,Trogoderma granarium infestation.This study determined the mortality percentage of 5th instar larvae ...According the importance of the stored grains and other products,it is an essential to keep them from khapra beetle,Trogoderma granarium infestation.This study determined the mortality percentage of 5th instar larvae of T.granarium fed on wheat seeds(25 gm)treated with different weights of silica as well as silica nanoparticles(20,40,60 and 80 mg)at different temperature(9℃,25℃,and 35℃).Study showed that using silica nanoparticles in cold temperature(9℃)was the most efficient treatment with the lowest LC_(50)(lethal concentration required to kill 50%of the population)value and caused the highest toxicity index.In contrast,the least efficient treatment(25℃)with the highest LC_(50) value and showed lowest toxicity index was using silica in normal temperature,when using silica nanoparticles,the cold temperature was the best condition followed by hot temperature(35℃)and finally the normal temperature.On the other hand,using silica in hot temperature was most effective followed by silica with cold temperature and finally silica with normal temperature.The biochemical assays revealed that the change in the experimental temperature had a nonsignificant effect on the total protein content of the larvae.The total lipids and total carbohydrates exhibited a significant increase due to hot treating.5th instar larvae of T.granarium treated with LC50 of silica at high temperature led to a nonsignificant(p≤0.05)decrease in Acetylcholinesterase(AchE)activity compared to treatment at normal temperature.In contrast,Glutathione S-transferase(GST)and Peroxidase activities were significantly(p≤0.05)raised due to the treatment conducted at high temperature.Additionally,treating larvae with LC50 of silica nanoparticles at low temperature caused a significant increase in both GST and peroxidase activities,while the increase in AChE was nonsignificantly(p≤0.05)compared to treatment at normal temperature.Using silica at low temperature could be used as an alternative to chemical insecticides to control T.granarium larvae.展开更多
A novel method for scandium recovery is proposed through high-surface area silanol-rich silica sorbents which were prepared with calcium silicate hydrate(C-S-H) as raw material.Two types of silanol-rich silica particl...A novel method for scandium recovery is proposed through high-surface area silanol-rich silica sorbents which were prepared with calcium silicate hydrate(C-S-H) as raw material.Two types of silanol-rich silica particles,i.e.,LAC-S(silica derived from acid leaching of amorphous C-S-H) and LLC-S(silica derived from acid leaching of low-crystallinity C-S-H) are obtained after calcium ions are removed from both amorphous and low-crystallinity forms of C-S-H through a facile acid leaching process(3 mol/L,25℃,24 h).(29)^Si NMR spectroscopy reveals that the proportion of silicon atoms carrying silanol groups increases from less than 43% to over 80% when silica particles are transferred from a dry state to an aqueous solution.Batch adsorption experiments were conducted to evaluate the sorption performance and selectivity of these silica sorbents toward Sc(Ⅲ).The scandium sorption capacities of LAC-S and LLC-S at an equilibrium pH of 4.2 are 174.45 and 129.57 mg/g,respectively.The separation factors(SFSc/Ln) of both silica particles exceed 1000 in the initial pH range of 3.5-5.The loaded scandium ions are recovered with 3 mol/L hydrochloric acid and the sorbents exhibit good reusability.This strategy provides an efficient and green method for recovering scandium from aqueous solutions.展开更多
Research on the effects of the amount of fillers in the form of fused alumina,mullite,and tabular alumina,zirconium-containing and silica-containing components of the batches in the form of zircon and silica sand on t...Research on the effects of the amount of fillers in the form of fused alumina,mullite,and tabular alumina,zirconium-containing and silica-containing components of the batches in the form of zircon and silica sand on the properties of alumina-zirconia-silicate(AZS)refractories was conducted.It was found that the introduction of 16%zircon into the composition of samples with fillers such as fused alumina and mullite,as well as tabular alumina,results in an increase in their density,strength,and thermal shock resistance.Petrographic studies have revealed the formation of a multiphase,microcracked structure in these samples,which accounts for the improvement in their properties.The optimal composition of a batch containing a filler of tabular alumina,a finely dispersed matrix ofα-alumina,16%zircon,and 7%silica sand has been determined,which ensures the production of AZS refractories with high bulk density,cold crushing strength,and thermal shock resistance.Research on the plastic strength of the structure of optimal composition AZS mass,depending on its storage time,was conducted.It was found that up to 24 h of storage,the mass is characterized by low plastic strength.It indicates its suitability for use in the vibration casting technology of products.Storage of the mass for more than 24 h leads to an increase in the plastic strength of its structure,which reaches a maximum after 56 h of storage.The developed composition of the batch is recommended for the manufacture of AZS crucibles for induction melting of heat-resistant alloys.展开更多
Due to excellent thermal insulation performance at room temperature and ultralow density,silica aero-gels are candidates for thermal insulation.However,at high temperatures,the thermal insulation prop-erty of silica a...Due to excellent thermal insulation performance at room temperature and ultralow density,silica aero-gels are candidates for thermal insulation.However,at high temperatures,the thermal insulation prop-erty of silica aerogels decreased greatly caused by transparency to heat radiation.Opacifiers introduced into silica sol can block heat radiation yet destroy the uniformity of aerogels.Herein,we designed and prepared a silica aerogel composite with oriented and layered silica fibers(SFs),SiC nanowires(SiC_(NWs)),and silica aerogels,which were prepared by papermaking,chemical vapor infiltration(CVI),and sol-gel respectively.Firstly,oriented and layered SFs made still air a wall to block heat transfer by the solid phase.Secondly,SiC_(NWs) were grown in situ on the surface of SFs evenly to weave into the network,and the network reduced the gaseous thermal conductivity by dividing cracks in SFs/SiC_(NWs)/SA.Thirdly,SiC_(NWs) weakened the heat transfer by radiation at high temperatures.Therefore,SFs/SiC_(NWs)/SA presented remarkable thermal insulation(0.017 W(m K)^(-1) at 25℃,0.0287 W(m K)^(-1) at 500℃,and 0.094 W(m K)^(-1) at 1000℃).Besides,SFs/SiC_(NWs)/SA exhibited remarkable thermal stability(no size transform after being heat treated at 1000℃ for 1800 s)and tensile strength(0.75 MPa).These integrated properties made SFs/SiC_(NWs)/SA a promising candidate for highly efficient thermal insulators.展开更多
Obesity has become a global threat to health;however,the available drugs for treating obesity are limited.We investigated the anti-obesity effect of hydroxy-α-sanshool(HAS),an amide derived from the fruit of Zanthoxy...Obesity has become a global threat to health;however,the available drugs for treating obesity are limited.We investigated the anti-obesity effect of hydroxy-α-sanshool(HAS),an amide derived from the fruit of Zanthoxylum bungeanum,which promotes the management of obesity by triggering the browning of white adipose tissue(WAT)targeting the membrane receptor of transient receptor potential vanilloid 1(TRPV1).However,HAS easily undergoes configuration transformation and oxidative degradation.The short peptide CKGGRAKDC or adipose-targeting sequence(ATS)binds specifically to prohibitin on the surface of WAT cells and can be used as recognition assembly to enhance adipocyte targetability.Furthermore,mesoporous silica nanoparticles(MSNs)are widely used in drug delivery systems because of their large specific surface area and pore volume.Therefore,HAS-loaded adipose-targeted MSNs(MSNs-ATS)were developed to enhance the adipocyte targetability,safety,and efficacy of HAS,and tested on mature 3T3-L1 cells and obese mouse models.MSNs-ATS showed higher specificity for adipocyte targetability without obvious toxicity.HAS-loaded MSNs-ATS showed anti-obesity effects superior to those of HAS alone.In conclusion,we successfully developed adipocyte-targeted,HAS-loaded MSNs with good safety and anti-obesity effects.展开更多
Epithelial-mesenchymal transition(EMT)plays an irreplaceable role in the development of silicosis.However,molecular mechanisms of EMT induced by silica exposure still remain to be addressed.Herein,metabolic profiles o...Epithelial-mesenchymal transition(EMT)plays an irreplaceable role in the development of silicosis.However,molecular mechanisms of EMT induced by silica exposure still remain to be addressed.Herein,metabolic profiles of human alveolar type II epithelial cells(A549 cells)exposed directly to silica were characterized using non-targeted metabolomic approaches.A total of 84 differential metabolites(DMs)were identified in silica-treated A549 cells undergoing EMT,which were mainly enriched in metabolisms of amino acids(e.g.,glutamate,alanine,aspartate),purine metabolism,glycolysis,etc.The number of DMs identified in the A549 cells obviously increased with the elevated exposure concentration of silica.Remarkably,glutamine catabolism was significantly promoted in the silica-treated A549 cells,and the levels of related metabolites(e.g.,succinate)and enzymes(e.g.,α-ketoglutarate(α-KG)dehydrogenase)were substantially up-regulated,with a preference toα-KG pathway.Supplementation of glutamine into the cell culture could substantially enhance the expression levels of both EMT-related markers and Snail(zinc finger transcription factor).Our results suggest that the EMT of human alveolar epithelial cells directly induced by silica can be essential to the development of silicosis.展开更多
To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid...To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid(CA)within the zein matrix(EG/CA-MSN/Zein)was developed.This study compared the effects of EG/CA-MSN/Zein,polyethylene(PE),and zein films on the quality of fish fillets during refrigerated storage.The results showed that the EG/CA-MSN/Zein film significantly retarded the increase in pH and microbial growth.Moreover,the film had higher water-holding capacity(WHC),better texture,and color stability,as indicated by low-field nuclear magnetic resonance(LF-NMR),magnetic resonance imaging(MRI),and sensory evaluation.The EG/CA-MSN/Zein composite film extended the shelf life of crucian carp fillets by 3-4 days,highlighting its potential as an environmentally friendly and efficient packaging material for aquatic products.展开更多
The micro-dispersion structure of silica fillers exerts significant infiuences on the performance characteristics of rubber-based products. How to monitor this parameter is an important issue in the rubber industry, b...The micro-dispersion structure of silica fillers exerts significant infiuences on the performance characteristics of rubber-based products. How to monitor this parameter is an important issue in the rubber industry, but there is currently no suitable technical solution for numerical monitoring that can be applied in automatic production line. The labeling of silica in rubber is a challenge that bottlenecks the development of numerical quality monitoring technology. In this work, we employed the organometallic europium to modify silica endowing the fiuorescence properties for characterization. It provides more feasible solutions for visually studying the relationship between the submicroscopic structure and macroscopic properties of inorganic-filled polymers, and is the key foundation for achieving numerical monitoring of rubber filler qualities in industry.展开更多
Ordered porous silica nanospheres with pores vertical to the walls were prepared by using 1,3,5-trimethyl-benzen(TMB)and hexadecitrile trimethyl ammonium bromide(CTAB)as templates.After removing the templates,porous s...Ordered porous silica nanospheres with pores vertical to the walls were prepared by using 1,3,5-trimethyl-benzen(TMB)and hexadecitrile trimethyl ammonium bromide(CTAB)as templates.After removing the templates,porous structures were obtained.The porous silica nanosperes were further modified with amino and amino acid functionalization to obtain L-Glutamic acid-functionalized mesoporous silica nanospheres,which were used as chiral selective agents for amino acid enantioseparation such as PheCOOH,PhgCOOH,and TrpCOOH enantiomers.The experimental results show that the functionalized nanospheres have good adsorption selectivity for D-PheCOOH and L-PhgCOOH,especially showing high adsorption selectivity for the L-TrpCOOH enantiomers compared with L-PheCOOH and D-PhgCOOH and D-TrpCOOH enantiomers.展开更多
The efficient storage and application of sustainable solar energy has drawn significant attention from both academic and industrial points of view.However,most developed catalytic materials still suffer from insuffici...The efficient storage and application of sustainable solar energy has drawn significant attention from both academic and industrial points of view.However,most developed catalytic materials still suffer from insufficient mass diffusion and unsatisfactory durability due to the lack of interconnected and regulatable porosity.Developing catalytic architectures with engineered active sites and prominent stability through rational synthesis strategies has become one of the core projects in solar-driven applications.The unique properties of mesoporous silicas render them among the most valuable functional materials for industrial applications,such as high specific surface area,regulatable porosity,adjustable surface properties,tunable particle sizes,and great thermal and mechanical stability.Mesoporous silicas serve as structural templates or catalytic supports to enhance light harvesting via the scattering effect and provide large surface areas for active site generation.These advantages have been widely utilized in solar applications,including hydrogen production,CO_(2)conversion,photovoltaics,biomass utilization,and pollutant degradation.To achieve the specific functionalities and desired activity,various types of mesoporous silicas from different synthesis methods have been customized and synthesized.Moreover,morphology regulation and component modification strategies have also been performed to endow mesoporous silica-based materials with unprecedented efficiency for solar energy storage and utilization.Nevertheless,reviews about synthesis,morphology regulation,and component modification strategies for mesoporous silica-based catalyst design in solar-driven applications are still limited.Herein,the latest progress concerning mesoporous silica-based catalysis in solar-driven applications is comprehensively reviewed.Synthesis principles,formation mechanisms,and rational functionalities of mesoporous silica are systematically summarized.Some typical catalysts with impressive activities in different solar-driven applications are highlighted.Furthermore,challenges and future potential opportunities in this study field are also discussed and proposed.This present review guides the design of mesoporous silica catalysts for efficient solar energy management for solar energy storage and conversion applications.展开更多
Metal nanoparticles used in high‐temperature catalytic reactions,such as dry reforming of methane,are prone to sintering,leading to particle growth,loss of active surface area,and eventual catalyst deactivation.This ...Metal nanoparticles used in high‐temperature catalytic reactions,such as dry reforming of methane,are prone to sintering,leading to particle growth,loss of active surface area,and eventual catalyst deactivation.This is particularly true for nickelbased catalysts,which,despite their high activity and low cost,often suffer from severe agglomeration and carbon deposition under harsh reforming conditions.Therefore,effectively preventing metal particle growth is crucial for achieving long‐term catalytic stability.In this work,we present a robust strategy to stabilize monodispersed Ni nanoclusters(NCs,1 wt.%)by anchoring them onto a silica‐coated silicon carbide support(SiC@SiO_(2)).The resulting Ni/SiC@SiO_(2) catalyst exhibited outstanding performance at 800℃,with 90%conversion for both CH_(4) and CO_(2).The Ni NCs maintained a uniform size(~1.8 nm)after stability testing,in contrast to the severe sintering(~9.3 nm)and low activity(<10%conversion)observed for Ni on unmodified SiC.The silica layers played a key role in chemically confining the Ni NCs,enhancing their dispersion and thermal stability.Furthermore,the formation of Ni‒O‒Si interfacial structures improved metal‐support interactions,effectively suppressing the reverse water–gas shift(RWGS)reaction and facilitating carbon oxidation via CO_(2) activation.This interfacial engineering strategy significantly enhanced the catalyst's resistance to both sintering and coking,offering a generalizable approach to designing durable metal catalysts for high‐temperature reactions.展开更多
An ionic liquid assisted hydrogel modified silica was synthesized using a one-pot polymerization and physical coating technique and subsequently applied to mixed-mode liquid chromatography.Analytical techniques,includ...An ionic liquid assisted hydrogel modified silica was synthesized using a one-pot polymerization and physical coating technique and subsequently applied to mixed-mode liquid chromatography.Analytical techniques,including Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and elemental analysis,etc.,confirmed the successful prepared of this innovative stationary phase.The unique combination of amide,long alkyl chain,and imidazole ring in the hydrogel coating enables the stationary phase to function effectively in hydrophilic/reversed-phase/ion exchange liquid chromatography.Notably,the stationary phase exhibited superior separation performance owing to the synergistic effect of the ionic liquid and hydrogel.This was particularly evident when analyzing various analytes such as organic acids,nucleosides/bases,polycyclic aromatic hydrocarbons(PAHs)and anions.Furthermore,under our operating conditions,an excellent column efficiency of 53,642.9 plates/m was achieved for theobromine.In summary,we have proposed a straightforward strategy to enhance the separation performance of hydrogel coatings in liquid chromatography,thereby broadening the potential applications of hydrogels in the field of separation.展开更多
Ceramic cores fabricated by stereolithography exhibit great potential in casting turbine blades.Previous research on ceramic core molding was primarily conducted using vertical printing techniques,which not only resul...Ceramic cores fabricated by stereolithography exhibit great potential in casting turbine blades.Previous research on ceramic core molding was primarily conducted using vertical printing techniques,which not only resulted in lengthy molding durations but also compromised the mechanical strength.In this work,silica(SiO--_2)ceramic cores,with fine complex geometric shapes,were fabricated using 65vol.%ceramic slurry by digital light processing(DLP)with different printing angles.Printing angles significantly impact the surface accuracy,shrinkage,printing efficiency of green bodies,as well as the microstructure and mechanical properties of sintered ceramic core samples.As the printing angle in the green body increases,the bonding area decreases,surface roughness on the XY plane worsens,shrinkage in the Z direction becomes more pronounced,and the printing efficiency declines.Similarly,an increase in the printing angle in the sintered body leads to a reduction in bending strength.At a printing angle of 30°,the printing time is reduced to half of that at 90°,which improves the molding efficiency.Meanwhile,the obtained bulk density of 1.71 g·cm~(-3),open porosity of 24%,and fiexural strength of 10.6±1 MPa can meet the requirements of sintered ceramic cores.Therefore,designing and optimizing the printing angles can achieve the balance between shrinkage,printing efficiency,and fiexural strength.展开更多
Laminated elastomeric bearings used in seismic isolation rely on the mechanical properties of their constituent elastomers to ensure effective performance.However,despite their resistance to temperature fluctuations a...Laminated elastomeric bearings used in seismic isolation rely on the mechanical properties of their constituent elastomers to ensure effective performance.However,despite their resistance to temperature fluctuations and environmental aggressors,silicone elastomers exhibit relatively low stiffness,limiting their direct applicability in seismic isolation.This study investigates the effect of fumed silica as a reinforcing filler to enhance the mechanical properties of laminated silicone elastomeric bearings.Elastomeric samples were fabricated with varying fumed silica proportions and subjected to Shore A hardness,uniaxial tensile,and lap shear tests to assess the influence of filler content.Additionally,quasi-static tests were conducted on reduced-scale bearing prototypes under combined vertical compression and cyclic horizontal shear to evaluate their seismic isolation performance.The results demonstrate that fumed silica reinforcement significantly increases stiffness,as evidenced by higher Shore A hardness values.However,a trade-off was observed in tensile properties,with reductions in tensile strength and elongation at break.Despite this,the equivalent elastic modulus did not show substantial variation up to large deformations,indicating that stiffness is preserved under most working conditions.Lap shear tests showed that fumed silica improves shear resistance,while quasi-static tests revealed inelastic behavior with small increases in equivalent shear coefficients but no substantial loss in damping ratios.These findings suggest that fumed silica reinforcement enhances silicone elastomers’stiffness and shear resistance while maintaining moderate damping properties,making it a promising approach for improving the mechanical performance of elastomeric bearings in seismic isolation applications.展开更多
文摘Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates significantly at elevated temperatures exceeding 600℃,primarily due to the collapse of pore structure.Meanwhile,the shielding capacity of SiO_(2) aerogel to the infrared radiation at high temperature is rather low due to the intrinsic properties of SiO_(2).Herein,a strategy for improving the high-temperature stability and infrared shielding properties of SiO_(2) aerogel via Ca doping was explored.Calcium-doped silica aerogel(CSA)powders were prepared by Sol-Gel,hydrothermal,and ambient pressure drying(APD)techniques using water glass and anhydrous calcium chloride as precursors and trimethylchlorosilane as a hydrophobic modifier.The effects of Ca/Si molar ratio in the precursor and hydrothermal conditions(temperature and pH)on the crystalline properties,microscopic morphology and pore structure of CSAs were investigated.The results show that the Ca/Si molar ratio and hydrothermal treatment have significant effects on the microstructure and heat resistance of CSAs in the temperature range of 400-1000℃.The samples sintered at 1000℃have a high specific surface area of 100.1 m^(2)/g and a pore volume of 0.8705 cm^(3)/g,indicating that the CSA has good heat resistance.One-side insulation tests at temperatures up to 600℃show that the sample with a Ca/Si molar ratio of 1.0 has the best insulation performance,with a cold surface temperature of 450℃,which is 27℃lower than that of the pure silica aerogel.
文摘Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms ligand bonds or hydrogen bonds with sulfur ions in lithium polysulfides(LiPSs),thus inhibiting the shuttle effect.Electrochemical analyses demonstrated that lithium‑sulfur(Li‑S)batteries employing the NH2‑SS interlayer exhibited discharge specific capacities of 1048 and 789 mAh·g^(-1) at 0.2C and 2C,respectively,and even at 4C,the initial discharge specific capacity remained at 590 mAh·g^(-1),outperforming the Li‑S battery with unmodified SS as the interlayer.
文摘The transport properties of liquid mixtures confined within porous media can change significantly from those observed for bulk mixtures due to changes in the liquid structuring within the pore space.Here,pulsed field gradient NMR was used to measure the diffusion coefficient of ethanol in ethanol-water liquid mixtures confined within silicas with pore diameters of 6 nm and 3 nm as a function of composition.For liquids imbibed within the 6 nm pores,the composition dependence of the ethanol diffusion coefficient closely followed that of the bulk liquid mixture and the absolute diffusion coefficients were reduced by a tortuosity factor of 3,with a minor contribution due to liquid-surface interactions.For liquids imbibed within the 3 nm pores,the diffusion coefficient of ethanol decreased as the composition of ethanol within the pore space increased,and for single-component ethanol imbibition the effective tortuosity was 63.Fast field cycling NMR experiments showed that the diffusion behaviour was not controlled by an increase in ethanol adsorption strength.A geometric analysis of the pore space was consistent with a highly confined system in which most molecules interacted with the pore walls.Under such confinement,the liquid structuring within the bulk pore space did not reflect that of the bulk liquid mixtures,and the observed decrease in diffusion coefficient as ethanol composition increased was consistent with an increase in confinement due to the larger size of the ethanol molecule.
基金supported by National Natural Science Foundation of China (Nos.21906124,32302202)Natural Science Foundation of Hubei Province (No.2017CFB220)Natural Science Foundation of Shandong Province (No.ZR2023MH278)。
文摘Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through covalent bonds exhibits excellent structural stability.It has been shown that the stationary phases prepared by combining MOF and COF can make up for the poor stability of MOF@SiO_(2),and the MOF/COF composites have superior chromatographic separation performance.However,the traditional methods for preparing COF/MOF based stationary phases are generally solvent thermal synthesis.In this study,a green and low-cost synthesis method was proposed for the preparation of MOF/COF@SiO_(2) stationary phase.Firstly,COF@SiO_(2) was prepared in a choline chloride/ethylene glycol based deep eutectic solvent(DES).Secondly,another acid-base tunable DES prepared by mixing p-toluenesulfonic acid(PTSA)and 2-methylimidazole in different proportions was introduced as the reaction solvent and reactant for rapid synthesis of MOF/COF@SiO_(2).Compared with the toxic transition metal-based MOFs selected in most previous studies,a lightweight and non-toxic S-zone metal(calcium) based MOF was employed in this study.PTSA and calcium will form the calcium/oxygen-containing organic acid framework in acidic DES,which assembles with terephthalic acid dissolved in basic DES to form MOF.The strong hydrogen bonding effect of DES can facilitate rapid assembly of Ca-MOF.The obtained Ca-MOF/COF@SiO_(2) can be used for multi-mode chromatography to efficiently separate multiple isomeric/hydrophilic/hydrophobic analytes.The synthesis method of Ca-MOF/COF@SiO_(2) is green and mild,especially the use of acid-base tunable DES promotes the rapid synthesis of non-toxic Ca-MOF/COF@silica composites,which offers an innovative approach of greenly synthesizing novel MOF/COF stationary phases and extends their applications in the field of chromatography.
基金National Key R&D Program of China(grant number 2022YFA1207500)National Natural Science Foundation of China(grant number 82072412).
文摘Treating bone defects complicated by bacterial infections remains a significant clinical challenge.Drawing inspiration from the human body's bone repair mechanisms,the use of biomimetic methods to design tissue engineering scaffolds is of great significance for bone repair.This study synthesized copper(Cu)-doped mesoporous silica nanoparticles(Cu@MSN)modified with hydroxyethyl methacrylate to obtain methacrylated Cu@MSN(Cu@MSNMA).Furtheremore,bio-mimetic nanocomposite hydrogels were prepared by adding Cu@MSNMA to a GelMA/gelatin solution.This hydrogel achieves multi-modal bone tissue biomimicry:(ⅰ)GelMA/gelatin mimics the matrix components in bone ECM,ensuring biocompatibility while promoting cellular behavior(such as adhesion,proliferation,and differentiation);(ⅱ)GelMA/gela-tin and the crosslinking sites introduced by Cu@MSNMA form a stable porous network structure,achieving structural and mechanical biomimicry to provide necessary support for bone defects;(ⅲ)The elemental biomimicry of Si and Cu in Cu@MSNMA achieves efficient osteogenic induction.The effect of different proportions of Cu@MSNMA on the physi-cal properties of the composite hydrogels was investigated to determine the optimal proportion.The results indicated that the mechanical properties of hydrogel were enhanced with the increasing Cu@MSNMA mass ratio.Notably,5%NPs/GelMA/gelatin hydrogel exhibited excellent mechanical property compared to the GelMA/gelatin hydrogel.In vitro and vivo cellular experiments demonstrated a significant enhancement in antibacterial and osteogenic induction with Cu@MSNMA addition.In conclusion,the proposed nanocomposite hydrogel with biomimetic components and ion-regulating properties can serve as a multifunctional scaffold,offering antimicrobial properties for infected bone regeneration,and guide for future research in bone regeneration and three-dimensional printing.
基金Funded by the Natural Science Foundation of Hubei Province(No.2024AFB833)。
文摘Silica fibers were modified by a specific ratio of SiB6 mixed with silica sol through vacuum impregnation method.The modified fibers were then incorporated into a phenolic resin matrix to prepare fiber-reinforced resin composites.The influences of the SiB_(6)/SiO_(2)mixed modification on silica fiber properties were analyzed through thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),scanning electron microscopy(SEM),and X-ray diffraction(XRD),respectively.Additionally,the influence of the SiB_(6)/SiO_(2)mixed modification on the mechanical properties of phenolic resin matrix composites was evaluated through mechanical testing.The experimeatal results indicate that the SiB_(6)/SiO_(2)mixed surface modification shows significant improvement in strength at room temperature and high temperatures,and crystallization temperature of silica fiber increases.The SiB_(6)/Silica sol co-modified silica fiber shows potential for future application in thermal protection and other high-temperature conditions.
文摘According the importance of the stored grains and other products,it is an essential to keep them from khapra beetle,Trogoderma granarium infestation.This study determined the mortality percentage of 5th instar larvae of T.granarium fed on wheat seeds(25 gm)treated with different weights of silica as well as silica nanoparticles(20,40,60 and 80 mg)at different temperature(9℃,25℃,and 35℃).Study showed that using silica nanoparticles in cold temperature(9℃)was the most efficient treatment with the lowest LC_(50)(lethal concentration required to kill 50%of the population)value and caused the highest toxicity index.In contrast,the least efficient treatment(25℃)with the highest LC_(50) value and showed lowest toxicity index was using silica in normal temperature,when using silica nanoparticles,the cold temperature was the best condition followed by hot temperature(35℃)and finally the normal temperature.On the other hand,using silica in hot temperature was most effective followed by silica with cold temperature and finally silica with normal temperature.The biochemical assays revealed that the change in the experimental temperature had a nonsignificant effect on the total protein content of the larvae.The total lipids and total carbohydrates exhibited a significant increase due to hot treating.5th instar larvae of T.granarium treated with LC50 of silica at high temperature led to a nonsignificant(p≤0.05)decrease in Acetylcholinesterase(AchE)activity compared to treatment at normal temperature.In contrast,Glutathione S-transferase(GST)and Peroxidase activities were significantly(p≤0.05)raised due to the treatment conducted at high temperature.Additionally,treating larvae with LC50 of silica nanoparticles at low temperature caused a significant increase in both GST and peroxidase activities,while the increase in AChE was nonsignificantly(p≤0.05)compared to treatment at normal temperature.Using silica at low temperature could be used as an alternative to chemical insecticides to control T.granarium larvae.
基金Project supported by the National Natural Science Foundation of China (52064002)Guangxi Science and Technology Major Project(AA23073018)。
文摘A novel method for scandium recovery is proposed through high-surface area silanol-rich silica sorbents which were prepared with calcium silicate hydrate(C-S-H) as raw material.Two types of silanol-rich silica particles,i.e.,LAC-S(silica derived from acid leaching of amorphous C-S-H) and LLC-S(silica derived from acid leaching of low-crystallinity C-S-H) are obtained after calcium ions are removed from both amorphous and low-crystallinity forms of C-S-H through a facile acid leaching process(3 mol/L,25℃,24 h).(29)^Si NMR spectroscopy reveals that the proportion of silicon atoms carrying silanol groups increases from less than 43% to over 80% when silica particles are transferred from a dry state to an aqueous solution.Batch adsorption experiments were conducted to evaluate the sorption performance and selectivity of these silica sorbents toward Sc(Ⅲ).The scandium sorption capacities of LAC-S and LLC-S at an equilibrium pH of 4.2 are 174.45 and 129.57 mg/g,respectively.The separation factors(SFSc/Ln) of both silica particles exceed 1000 in the initial pH range of 3.5-5.The loaded scandium ions are recovered with 3 mol/L hydrochloric acid and the sorbents exhibit good reusability.This strategy provides an efficient and green method for recovering scandium from aqueous solutions.
文摘Research on the effects of the amount of fillers in the form of fused alumina,mullite,and tabular alumina,zirconium-containing and silica-containing components of the batches in the form of zircon and silica sand on the properties of alumina-zirconia-silicate(AZS)refractories was conducted.It was found that the introduction of 16%zircon into the composition of samples with fillers such as fused alumina and mullite,as well as tabular alumina,results in an increase in their density,strength,and thermal shock resistance.Petrographic studies have revealed the formation of a multiphase,microcracked structure in these samples,which accounts for the improvement in their properties.The optimal composition of a batch containing a filler of tabular alumina,a finely dispersed matrix ofα-alumina,16%zircon,and 7%silica sand has been determined,which ensures the production of AZS refractories with high bulk density,cold crushing strength,and thermal shock resistance.Research on the plastic strength of the structure of optimal composition AZS mass,depending on its storage time,was conducted.It was found that up to 24 h of storage,the mass is characterized by low plastic strength.It indicates its suitability for use in the vibration casting technology of products.Storage of the mass for more than 24 h leads to an increase in the plastic strength of its structure,which reaches a maximum after 56 h of storage.The developed composition of the batch is recommended for the manufacture of AZS crucibles for induction melting of heat-resistant alloys.
基金supported by the National Natural Science Foun-dation of China(Grant No.U2167214).
文摘Due to excellent thermal insulation performance at room temperature and ultralow density,silica aero-gels are candidates for thermal insulation.However,at high temperatures,the thermal insulation prop-erty of silica aerogels decreased greatly caused by transparency to heat radiation.Opacifiers introduced into silica sol can block heat radiation yet destroy the uniformity of aerogels.Herein,we designed and prepared a silica aerogel composite with oriented and layered silica fibers(SFs),SiC nanowires(SiC_(NWs)),and silica aerogels,which were prepared by papermaking,chemical vapor infiltration(CVI),and sol-gel respectively.Firstly,oriented and layered SFs made still air a wall to block heat transfer by the solid phase.Secondly,SiC_(NWs) were grown in situ on the surface of SFs evenly to weave into the network,and the network reduced the gaseous thermal conductivity by dividing cracks in SFs/SiC_(NWs)/SA.Thirdly,SiC_(NWs) weakened the heat transfer by radiation at high temperatures.Therefore,SFs/SiC_(NWs)/SA presented remarkable thermal insulation(0.017 W(m K)^(-1) at 25℃,0.0287 W(m K)^(-1) at 500℃,and 0.094 W(m K)^(-1) at 1000℃).Besides,SFs/SiC_(NWs)/SA exhibited remarkable thermal stability(no size transform after being heat treated at 1000℃ for 1800 s)and tensile strength(0.75 MPa).These integrated properties made SFs/SiC_(NWs)/SA a promising candidate for highly efficient thermal insulators.
基金supported by the Natural Science Foundation of Sichuan Province(No.2022NSFSC0720)Research Center for the Development of the Comprehensive Health Industry and Rural Revitalization of Sichuan TCM(No.DJKYB202306)State Administration of Traditional Chinese Medicine of Sichuan Province of China(No.2020HJZX001).
文摘Obesity has become a global threat to health;however,the available drugs for treating obesity are limited.We investigated the anti-obesity effect of hydroxy-α-sanshool(HAS),an amide derived from the fruit of Zanthoxylum bungeanum,which promotes the management of obesity by triggering the browning of white adipose tissue(WAT)targeting the membrane receptor of transient receptor potential vanilloid 1(TRPV1).However,HAS easily undergoes configuration transformation and oxidative degradation.The short peptide CKGGRAKDC or adipose-targeting sequence(ATS)binds specifically to prohibitin on the surface of WAT cells and can be used as recognition assembly to enhance adipocyte targetability.Furthermore,mesoporous silica nanoparticles(MSNs)are widely used in drug delivery systems because of their large specific surface area and pore volume.Therefore,HAS-loaded adipose-targeted MSNs(MSNs-ATS)were developed to enhance the adipocyte targetability,safety,and efficacy of HAS,and tested on mature 3T3-L1 cells and obese mouse models.MSNs-ATS showed higher specificity for adipocyte targetability without obvious toxicity.HAS-loaded MSNs-ATS showed anti-obesity effects superior to those of HAS alone.In conclusion,we successfully developed adipocyte-targeted,HAS-loaded MSNs with good safety and anti-obesity effects.
基金supported by the National Natural Science Foundation of China(Nos.22206207,22127810,and 22276224)the Natural Science Foundation of Guangdong Province(Nos.2021A1515011546 and 2023A1515010085)the Science and Technology Planning Project of Guangzhou(No.202102080005)。
文摘Epithelial-mesenchymal transition(EMT)plays an irreplaceable role in the development of silicosis.However,molecular mechanisms of EMT induced by silica exposure still remain to be addressed.Herein,metabolic profiles of human alveolar type II epithelial cells(A549 cells)exposed directly to silica were characterized using non-targeted metabolomic approaches.A total of 84 differential metabolites(DMs)were identified in silica-treated A549 cells undergoing EMT,which were mainly enriched in metabolisms of amino acids(e.g.,glutamate,alanine,aspartate),purine metabolism,glycolysis,etc.The number of DMs identified in the A549 cells obviously increased with the elevated exposure concentration of silica.Remarkably,glutamine catabolism was significantly promoted in the silica-treated A549 cells,and the levels of related metabolites(e.g.,succinate)and enzymes(e.g.,α-ketoglutarate(α-KG)dehydrogenase)were substantially up-regulated,with a preference toα-KG pathway.Supplementation of glutamine into the cell culture could substantially enhance the expression levels of both EMT-related markers and Snail(zinc finger transcription factor).Our results suggest that the EMT of human alveolar epithelial cells directly induced by silica can be essential to the development of silicosis.
文摘To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid(CA)within the zein matrix(EG/CA-MSN/Zein)was developed.This study compared the effects of EG/CA-MSN/Zein,polyethylene(PE),and zein films on the quality of fish fillets during refrigerated storage.The results showed that the EG/CA-MSN/Zein film significantly retarded the increase in pH and microbial growth.Moreover,the film had higher water-holding capacity(WHC),better texture,and color stability,as indicated by low-field nuclear magnetic resonance(LF-NMR),magnetic resonance imaging(MRI),and sensory evaluation.The EG/CA-MSN/Zein composite film extended the shelf life of crucian carp fillets by 3-4 days,highlighting its potential as an environmentally friendly and efficient packaging material for aquatic products.
基金financially supported by the Yangzhou Key Research and Development Program: Industry Foresight and Key Core Technology (No. YZ2023019)Cooperation Project of Yangzhou City with Yangzhou University (No. YZ2023209)+2 种基金Jiangsu Provincial Six Talent Peaks Project (No. XCL-090)Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)Yangzhou Bangjie New Materials Co., Ltd. for support。
文摘The micro-dispersion structure of silica fillers exerts significant infiuences on the performance characteristics of rubber-based products. How to monitor this parameter is an important issue in the rubber industry, but there is currently no suitable technical solution for numerical monitoring that can be applied in automatic production line. The labeling of silica in rubber is a challenge that bottlenecks the development of numerical quality monitoring technology. In this work, we employed the organometallic europium to modify silica endowing the fiuorescence properties for characterization. It provides more feasible solutions for visually studying the relationship between the submicroscopic structure and macroscopic properties of inorganic-filled polymers, and is the key foundation for achieving numerical monitoring of rubber filler qualities in industry.
基金Funded by the Opening Funding of the Provincial and Ministerial Joint Construction of the State Key Laboratory of New Textile Materials and Advanced Processing Technology(No.FZ2020003)the Science and Technology Innovation Program of Wuhan Textile University(No.233060)。
文摘Ordered porous silica nanospheres with pores vertical to the walls were prepared by using 1,3,5-trimethyl-benzen(TMB)and hexadecitrile trimethyl ammonium bromide(CTAB)as templates.After removing the templates,porous structures were obtained.The porous silica nanosperes were further modified with amino and amino acid functionalization to obtain L-Glutamic acid-functionalized mesoporous silica nanospheres,which were used as chiral selective agents for amino acid enantioseparation such as PheCOOH,PhgCOOH,and TrpCOOH enantiomers.The experimental results show that the functionalized nanospheres have good adsorption selectivity for D-PheCOOH and L-PhgCOOH,especially showing high adsorption selectivity for the L-TrpCOOH enantiomers compared with L-PheCOOH and D-PhgCOOH and D-TrpCOOH enantiomers.
基金financially supported by the Ningbo Institute of Digital Twin,Eastern Institute of Technology,Ningbo.We also acknowledge supportfrom the Young Innovative Talent of Yongjiang Talent Project(2023A‐387‐G).
文摘The efficient storage and application of sustainable solar energy has drawn significant attention from both academic and industrial points of view.However,most developed catalytic materials still suffer from insufficient mass diffusion and unsatisfactory durability due to the lack of interconnected and regulatable porosity.Developing catalytic architectures with engineered active sites and prominent stability through rational synthesis strategies has become one of the core projects in solar-driven applications.The unique properties of mesoporous silicas render them among the most valuable functional materials for industrial applications,such as high specific surface area,regulatable porosity,adjustable surface properties,tunable particle sizes,and great thermal and mechanical stability.Mesoporous silicas serve as structural templates or catalytic supports to enhance light harvesting via the scattering effect and provide large surface areas for active site generation.These advantages have been widely utilized in solar applications,including hydrogen production,CO_(2)conversion,photovoltaics,biomass utilization,and pollutant degradation.To achieve the specific functionalities and desired activity,various types of mesoporous silicas from different synthesis methods have been customized and synthesized.Moreover,morphology regulation and component modification strategies have also been performed to endow mesoporous silica-based materials with unprecedented efficiency for solar energy storage and utilization.Nevertheless,reviews about synthesis,morphology regulation,and component modification strategies for mesoporous silica-based catalyst design in solar-driven applications are still limited.Herein,the latest progress concerning mesoporous silica-based catalysis in solar-driven applications is comprehensively reviewed.Synthesis principles,formation mechanisms,and rational functionalities of mesoporous silica are systematically summarized.Some typical catalysts with impressive activities in different solar-driven applications are highlighted.Furthermore,challenges and future potential opportunities in this study field are also discussed and proposed.This present review guides the design of mesoporous silica catalysts for efficient solar energy management for solar energy storage and conversion applications.
基金supported by National Key Research and Development Program of China(Grant No.2022YFB4101200)the National Natural Science Foundation of China(Grant Nos.22072184 and 22372199)the Young Top‐notch Talent Cultivation Program of Hubei Province.
文摘Metal nanoparticles used in high‐temperature catalytic reactions,such as dry reforming of methane,are prone to sintering,leading to particle growth,loss of active surface area,and eventual catalyst deactivation.This is particularly true for nickelbased catalysts,which,despite their high activity and low cost,often suffer from severe agglomeration and carbon deposition under harsh reforming conditions.Therefore,effectively preventing metal particle growth is crucial for achieving long‐term catalytic stability.In this work,we present a robust strategy to stabilize monodispersed Ni nanoclusters(NCs,1 wt.%)by anchoring them onto a silica‐coated silicon carbide support(SiC@SiO_(2)).The resulting Ni/SiC@SiO_(2) catalyst exhibited outstanding performance at 800℃,with 90%conversion for both CH_(4) and CO_(2).The Ni NCs maintained a uniform size(~1.8 nm)after stability testing,in contrast to the severe sintering(~9.3 nm)and low activity(<10%conversion)observed for Ni on unmodified SiC.The silica layers played a key role in chemically confining the Ni NCs,enhancing their dispersion and thermal stability.Furthermore,the formation of Ni‒O‒Si interfacial structures improved metal‐support interactions,effectively suppressing the reverse water–gas shift(RWGS)reaction and facilitating carbon oxidation via CO_(2) activation.This interfacial engineering strategy significantly enhanced the catalyst's resistance to both sintering and coking,offering a generalizable approach to designing durable metal catalysts for high‐temperature reactions.
基金Innovation Groups of Basic Research in Gansu Province(No.23JRRA570)。
文摘An ionic liquid assisted hydrogel modified silica was synthesized using a one-pot polymerization and physical coating technique and subsequently applied to mixed-mode liquid chromatography.Analytical techniques,including Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and elemental analysis,etc.,confirmed the successful prepared of this innovative stationary phase.The unique combination of amide,long alkyl chain,and imidazole ring in the hydrogel coating enables the stationary phase to function effectively in hydrophilic/reversed-phase/ion exchange liquid chromatography.Notably,the stationary phase exhibited superior separation performance owing to the synergistic effect of the ionic liquid and hydrogel.This was particularly evident when analyzing various analytes such as organic acids,nucleosides/bases,polycyclic aromatic hydrocarbons(PAHs)and anions.Furthermore,under our operating conditions,an excellent column efficiency of 53,642.9 plates/m was achieved for theobromine.In summary,we have proposed a straightforward strategy to enhance the separation performance of hydrogel coatings in liquid chromatography,thereby broadening the potential applications of hydrogels in the field of separation.
基金the Youth Innovation Promotion Association of Chinese Academy of Science(No.2021160)the National Natural Science Foundation of China(No.51802319)the Technology and Engineering Center for Space(No.CSU-QZKT-2019-04)。
文摘Ceramic cores fabricated by stereolithography exhibit great potential in casting turbine blades.Previous research on ceramic core molding was primarily conducted using vertical printing techniques,which not only resulted in lengthy molding durations but also compromised the mechanical strength.In this work,silica(SiO--_2)ceramic cores,with fine complex geometric shapes,were fabricated using 65vol.%ceramic slurry by digital light processing(DLP)with different printing angles.Printing angles significantly impact the surface accuracy,shrinkage,printing efficiency of green bodies,as well as the microstructure and mechanical properties of sintered ceramic core samples.As the printing angle in the green body increases,the bonding area decreases,surface roughness on the XY plane worsens,shrinkage in the Z direction becomes more pronounced,and the printing efficiency declines.Similarly,an increase in the printing angle in the sintered body leads to a reduction in bending strength.At a printing angle of 30°,the printing time is reduced to half of that at 90°,which improves the molding efficiency.Meanwhile,the obtained bulk density of 1.71 g·cm~(-3),open porosity of 24%,and fiexural strength of 10.6±1 MPa can meet the requirements of sintered ceramic cores.Therefore,designing and optimizing the printing angles can achieve the balance between shrinkage,printing efficiency,and fiexural strength.
文摘Laminated elastomeric bearings used in seismic isolation rely on the mechanical properties of their constituent elastomers to ensure effective performance.However,despite their resistance to temperature fluctuations and environmental aggressors,silicone elastomers exhibit relatively low stiffness,limiting their direct applicability in seismic isolation.This study investigates the effect of fumed silica as a reinforcing filler to enhance the mechanical properties of laminated silicone elastomeric bearings.Elastomeric samples were fabricated with varying fumed silica proportions and subjected to Shore A hardness,uniaxial tensile,and lap shear tests to assess the influence of filler content.Additionally,quasi-static tests were conducted on reduced-scale bearing prototypes under combined vertical compression and cyclic horizontal shear to evaluate their seismic isolation performance.The results demonstrate that fumed silica reinforcement significantly increases stiffness,as evidenced by higher Shore A hardness values.However,a trade-off was observed in tensile properties,with reductions in tensile strength and elongation at break.Despite this,the equivalent elastic modulus did not show substantial variation up to large deformations,indicating that stiffness is preserved under most working conditions.Lap shear tests showed that fumed silica improves shear resistance,while quasi-static tests revealed inelastic behavior with small increases in equivalent shear coefficients but no substantial loss in damping ratios.These findings suggest that fumed silica reinforcement enhances silicone elastomers’stiffness and shear resistance while maintaining moderate damping properties,making it a promising approach for improving the mechanical performance of elastomeric bearings in seismic isolation applications.
