Background:Silica nanoparticles(SiNPs),commonly utilized in industrial and biomedical fields,are known to provoke pulmonary inflammation by elevating cyclooxygenase-2(COX-2)levels in human pulmonary alveolar epithelia...Background:Silica nanoparticles(SiNPs),commonly utilized in industrial and biomedical fields,are known to provoke pulmonary inflammation by elevating cyclooxygenase-2(COX-2)levels in human pulmonary alveolar epithelial cells(HPAEpiCs).Salvianolic acid A(SAA),a water-soluble polyphenol extracted from Salvia miltiorrhiza(Danshen),possesses well-documented antioxidant and anti-inflammatory activities.Nevertheless,its potential to counteract SiNP-induced inflammatory responses in the lung has not been thoroughly explored.Objective:This study aimed to evaluate the protective role and mechanistic actions of SAA against SiNP-triggered inflammation in both cellular and animal models.Methods:HPAEpiCs were pre-incubated with SAA prior to SiNP exposure to investigate changes in COX-2 expression and prostaglandin E2(PGE2)secretion.A murine model of SiNP-induced lung inflammation was used for in vivo validation.Key inflammatory signaling proteins,including c-Src,PKCα,p42/p44MAPK,and NF-κB p65,were analyzed for phosphorylation status.NF-κB promoter activity was also assessed.Pharmacological inhibitors and siRNA-mediated silencing were employed to verify the signaling cascade responsible for COX-2 regulation.Results:SAA treatment markedly suppressed SiNP-induced upregulation of COX-2 and PGE2 in bothHPAEpiCs andmouse lung tissues.SAA also reduced the activation(phosphorylation)of c-Src,PKCα,p42/p44 MAPK,and NF-κB p65,alongside diminishing NF-κB transcriptional activity.Functional studies using inhibitors and gene silencing further supported the involvement of these pathways inmediating the observed anti-inflammatory effect.Conclusion:By concurrently targeting several upstream pro-inflammatory signaling pathways,SAA demonstrates robust potential in alleviating SiNP-induced lung inflammation.These results highlight SAA as a promising candidate for therapeutic intervention in environmentally triggered respiratory conditions.展开更多
Point source CO_(2) capture(PSCC)is crucial for decarbonizing various industrial sectors,while direct air capture(DAC)holds promise for removing CO_(2) directly from the air.Sorbents play a critical role in both techn...Point source CO_(2) capture(PSCC)is crucial for decarbonizing various industrial sectors,while direct air capture(DAC)holds promise for removing CO_(2) directly from the air.Sorbents play a critical role in both technologies,with their performances,efficiency,cost,etc.,largely depending on which type is used(physical or chemical).Solid amine sorbents(SAS)employed in the chemical adsorption of CO_(2) are suitable for both PSCC and DAC.SAS offer significant advantages over liquid amines such as monoethanolamine(MEA),due to their ability to perform cyclic adsorption–desorption with much lower energy requirement.The environmental concern associated with MEA can be mitigated by SAS.Support materials have a significantly important role in stabilizing amine and enhancing stability and kinetics;varieties of support materials have been screened at a laboratory scale.One promising support material is a silica gel(SG),which is commercially available and attractive for designing cost-effective sorbents for large-scale CO_(2) capture.Various impregnation methods such as physical adsorption and covalent functionalization have been employed to functionalize silica surfaces with amines.This review provided a comprehensive critical analysis of SG-based SAS for CO_(2) capture.We discussed and evaluated them in terms of their adsorption capacity,adsorption,and desorption conditions,and the kinetics involved in these processes.Finally,we proposed a few recommendations for further development of low-cost,lower carbon footprint SAS for large-scale deployment of CO_(2) capture technology.展开更多
A Ti_(3)SiC_(2)-modified high-silica oxygen/phenolic aerogel composite with excellent oxidation resistance and high-temperature performance was prepared.The experimental results show that the obtained composite has si...A Ti_(3)SiC_(2)-modified high-silica oxygen/phenolic aerogel composite with excellent oxidation resistance and high-temperature performance was prepared.The experimental results show that the obtained composite has significantly improved oxidation resistance.When the addition amount of Ti_(3)SiC_(2)is 75%,the carbonization volume shrinkage rate of the composite after aerobic static combustion is only 5.95%.At the same time,the LAR and MAR after 30 seconds of oxyacetylene ablation under a heat flux density of 1.5 MW/m2 are 0.0307 mm/s and 0.0149 g/s,respectively.The compressive strength after aerobic static combustion at 1000℃is up to 20.43%of that before aerobic static combustion,which is 1.99 times that of the unfilled material,significantly improving the high-temperature mechanical properties of the composite.展开更多
Thermodynamic/dynamic modeling of liquid immiscibility in silicates is seriously hindered due to lack of in situ investigation on the structural evolution of the melt.In this work,atomic-scale structural evolution of ...Thermodynamic/dynamic modeling of liquid immiscibility in silicates is seriously hindered due to lack of in situ investigation on the structural evolution of the melt.In this work,atomic-scale structural evolution of a classic binary silicate immiscible system,SiO2–TiO2,is tracked by in situ high energy X-ray diffraction(HE-XRD).It is found that both the configuration of[SiO]and the polymerization between them are closely coupled with embedment and extraction of the metallic cations(Ti^4+).[SiO]monomer goes through deficit-oxygen and excess-polymerization before liquid–liquid separation and enables self-healing after liquid–liquid separation,which challenges the traditional cognition that[SiO4]monomer is immutable.Ti4+cations with tetrahedral oxygen-coordination first participate in the network construction before liquid separation.The four-fold Ti–O bond is broken during liquid separation,which may facilitate the movement of Ti4+across the Si–O network to form TiO2-rich nodules.The structural features of nodules were also investigated and they were found highly analogous to that of molten TiO2,which implies a parallel crystallization behavior in the two circumstances.Our results shed light on the structural evolution scenario in liquid immiscibility at atomic scale,which will contribute to constructing a complete thermodynamic/dynamic framework describing the silicate liquid immiscibility systems beyond current models.展开更多
SiO_(2)is the main component of gangue in sinters and a crucial constituent in the formation of the SiO_(2)–Fe_(2)O_(3)–Cao(SFC)system.The non-isothermal crystallization kinetics of the SFC system were investigated ...SiO_(2)is the main component of gangue in sinters and a crucial constituent in the formation of the SiO_(2)–Fe_(2)O_(3)–Cao(SFC)system.The non-isothermal crystallization kinetics of the SFC system were investigated using differential scanning calorimetry.The crystallization process of SFC was studied under different cooling rates(5,10,15,and 20 K/min),and the crystalline phases and microstructures of the SFC crystals were verified through X-ray diffraction and scanning electron microscopy.The results indicate that when the SiO_(2)content is 2 wt.%,increasing the cooling rate promotes the precipitation of CaFe_(2)O_(4)(CF)in the SFC system,thereby inhibiting the precipitation of Ca_(2)Fe_(2)O_(5)(C_(2)F).In contrast to the Cao–Fe_(2)O_(3)(C–F)system,the addition of SiO_(2)does not alter the precipitation mechanisms of C_(2)F and CF.By further adding SiO_(2),the precipitation of Ca_(2)Sio_(4)(C_(2)S)significantly increases.Simultaneously,the Cao content in the liquid phase decreases.This leads to the crystallization process of the CF_(4)S(4 wt.%Sio_(2))system bypassing the precipitation of C_(2)F and directly forming CF and CaFe_(4)O_(7)(CF_(2)).In the case of the CF_(8)S(8 wt.%SiO_(2))system,the crystallization process skips the precipitation of C_(2)F and CF,directly yielding CF_(2).The crystallization process of both CF_(2)S(2 wt.%Sio_(2))and CF is similar,comprising two reaction stages.The Ozawa method was used to calculate the activation energy for the crystallization of C_(2)F and CF as-329 and-419 kJ/mol,respectively.Analysis using the Malek method reveals model functions for both stages.展开更多
Modulation of Si-O bonds under mild conditions has been a challenging issue in the field of material science,which is critical to manufacture highperformance silica-based optical and photonic devices.Herein,we introdu...Modulation of Si-O bonds under mild conditions has been a challenging issue in the field of material science,which is critical to manufacture highperformance silica-based optical and photonic devices.Herein,we introduce a nondestructive technique to achieve Si-O bond rearrangement,leading to plastic deformation and photoluminescence enhancement of amorphous silica nanoparticles using supercritical carbon dioxides in EtOH/H_(2)O solution under mild temperature.Specifically,plastic deformation is achieved by treating hollow mesoporous silica nanospheres using supercritical CO_(2)at 40°C under 20 MPa.Experimental and theoretical studies revealed the critical role of supercritical CO_(2)in the plastic deformation process,which can be intercalated into the hollow mesoporous silica nanospheres with anisotropic stresses and induces the rearrangement of Si-O bonds and transformation of ring structures.This work suggests a novel approach to engineer high-performance nano-silica glass components for numerous optical and photonic devices under mild condition.展开更多
Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially acces...Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially accessible internal spaces,and so forth.Dissimilar vip species(such as organic groups or metal nanoparticles)could be readily decorated onto the interfaces of the channels and pores,realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications.As adsorbents and catalysts,dendritic mesoporous silica nanoparticles-based materials have experienced nonignorable development in CO_(2)capture and catalytic conversion.This comprehensive review provides a critical survey on this pregnant subject,summarizing the designed construction of novel dendritic mesoporous silica nanoparticles-based materials,the involved chemical reactions(such as CO_(2)methanation,dry reforming of CH_(4)),the value-added chemicals from CO_(2)(such as cyclic carbonates,2-oxazolidinones,quinazoline-2,4(1H,3H)-diones),and so on.The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials(such as SBA-15 or MCM-41),and the corresponding reaction mechanisms have been thoroughly revealed.It is sincerely expected that the in-depth discussion could give materials scientists certain inspiration to design brand-new dendritic mesoporous silica nanoparticles-based materials with superior capabilities towards CO_(2)capture,utilization,and storage.展开更多
基金supported by the National Science and Technology Council,Taiwan[Grant number:NSTC111-2320-B-030-013]as well as the Chang Gung University of Science Foundation,Taiwan[Grant number:ZRRPF6N0011].
文摘Background:Silica nanoparticles(SiNPs),commonly utilized in industrial and biomedical fields,are known to provoke pulmonary inflammation by elevating cyclooxygenase-2(COX-2)levels in human pulmonary alveolar epithelial cells(HPAEpiCs).Salvianolic acid A(SAA),a water-soluble polyphenol extracted from Salvia miltiorrhiza(Danshen),possesses well-documented antioxidant and anti-inflammatory activities.Nevertheless,its potential to counteract SiNP-induced inflammatory responses in the lung has not been thoroughly explored.Objective:This study aimed to evaluate the protective role and mechanistic actions of SAA against SiNP-triggered inflammation in both cellular and animal models.Methods:HPAEpiCs were pre-incubated with SAA prior to SiNP exposure to investigate changes in COX-2 expression and prostaglandin E2(PGE2)secretion.A murine model of SiNP-induced lung inflammation was used for in vivo validation.Key inflammatory signaling proteins,including c-Src,PKCα,p42/p44MAPK,and NF-κB p65,were analyzed for phosphorylation status.NF-κB promoter activity was also assessed.Pharmacological inhibitors and siRNA-mediated silencing were employed to verify the signaling cascade responsible for COX-2 regulation.Results:SAA treatment markedly suppressed SiNP-induced upregulation of COX-2 and PGE2 in bothHPAEpiCs andmouse lung tissues.SAA also reduced the activation(phosphorylation)of c-Src,PKCα,p42/p44 MAPK,and NF-κB p65,alongside diminishing NF-κB transcriptional activity.Functional studies using inhibitors and gene silencing further supported the involvement of these pathways inmediating the observed anti-inflammatory effect.Conclusion:By concurrently targeting several upstream pro-inflammatory signaling pathways,SAA demonstrates robust potential in alleviating SiNP-induced lung inflammation.These results highlight SAA as a promising candidate for therapeutic intervention in environmentally triggered respiratory conditions.
基金financial support from Business Finland 8205/31/2022the Magnus Ehrnrooth Foundation for financial support.
文摘Point source CO_(2) capture(PSCC)is crucial for decarbonizing various industrial sectors,while direct air capture(DAC)holds promise for removing CO_(2) directly from the air.Sorbents play a critical role in both technologies,with their performances,efficiency,cost,etc.,largely depending on which type is used(physical or chemical).Solid amine sorbents(SAS)employed in the chemical adsorption of CO_(2) are suitable for both PSCC and DAC.SAS offer significant advantages over liquid amines such as monoethanolamine(MEA),due to their ability to perform cyclic adsorption–desorption with much lower energy requirement.The environmental concern associated with MEA can be mitigated by SAS.Support materials have a significantly important role in stabilizing amine and enhancing stability and kinetics;varieties of support materials have been screened at a laboratory scale.One promising support material is a silica gel(SG),which is commercially available and attractive for designing cost-effective sorbents for large-scale CO_(2) capture.Various impregnation methods such as physical adsorption and covalent functionalization have been employed to functionalize silica surfaces with amines.This review provided a comprehensive critical analysis of SG-based SAS for CO_(2) capture.We discussed and evaluated them in terms of their adsorption capacity,adsorption,and desorption conditions,and the kinetics involved in these processes.Finally,we proposed a few recommendations for further development of low-cost,lower carbon footprint SAS for large-scale deployment of CO_(2) capture technology.
基金Funded by by the Wuhan Science and Technology Project(No.2024010702030141)。
文摘A Ti_(3)SiC_(2)-modified high-silica oxygen/phenolic aerogel composite with excellent oxidation resistance and high-temperature performance was prepared.The experimental results show that the obtained composite has significantly improved oxidation resistance.When the addition amount of Ti_(3)SiC_(2)is 75%,the carbonization volume shrinkage rate of the composite after aerobic static combustion is only 5.95%.At the same time,the LAR and MAR after 30 seconds of oxyacetylene ablation under a heat flux density of 1.5 MW/m2 are 0.0307 mm/s and 0.0149 g/s,respectively.The compressive strength after aerobic static combustion at 1000℃is up to 20.43%of that before aerobic static combustion,which is 1.99 times that of the unfilled material,significantly improving the high-temperature mechanical properties of the composite.
基金supported by the National Natural Science Foundation of China-Excellent Young Scholars(No.51922068)the National Key Research and Development Program(No.2017YFA0403800)+1 种基金the National Natural Science Foundation of China(Nos.51727802,51821001 and 51971138)Shanghai Pujiang Program(No.19PJ1404400)。
文摘Thermodynamic/dynamic modeling of liquid immiscibility in silicates is seriously hindered due to lack of in situ investigation on the structural evolution of the melt.In this work,atomic-scale structural evolution of a classic binary silicate immiscible system,SiO2–TiO2,is tracked by in situ high energy X-ray diffraction(HE-XRD).It is found that both the configuration of[SiO]and the polymerization between them are closely coupled with embedment and extraction of the metallic cations(Ti^4+).[SiO]monomer goes through deficit-oxygen and excess-polymerization before liquid–liquid separation and enables self-healing after liquid–liquid separation,which challenges the traditional cognition that[SiO4]monomer is immutable.Ti4+cations with tetrahedral oxygen-coordination first participate in the network construction before liquid separation.The four-fold Ti–O bond is broken during liquid separation,which may facilitate the movement of Ti4+across the Si–O network to form TiO2-rich nodules.The structural features of nodules were also investigated and they were found highly analogous to that of molten TiO2,which implies a parallel crystallization behavior in the two circumstances.Our results shed light on the structural evolution scenario in liquid immiscibility at atomic scale,which will contribute to constructing a complete thermodynamic/dynamic framework describing the silicate liquid immiscibility systems beyond current models.
基金This work was supported by the National Natural Science Foundation of China(52204331)Natural Science Foundation of Anhui Province Youth Project(2208085QE145)the Open Project Program of Key Laboratory of Metallurgical Emission Reduction&Resources Recycling(Anhui University of Technology),Ministry of Education(JKF20–03).
文摘SiO_(2)is the main component of gangue in sinters and a crucial constituent in the formation of the SiO_(2)–Fe_(2)O_(3)–Cao(SFC)system.The non-isothermal crystallization kinetics of the SFC system were investigated using differential scanning calorimetry.The crystallization process of SFC was studied under different cooling rates(5,10,15,and 20 K/min),and the crystalline phases and microstructures of the SFC crystals were verified through X-ray diffraction and scanning electron microscopy.The results indicate that when the SiO_(2)content is 2 wt.%,increasing the cooling rate promotes the precipitation of CaFe_(2)O_(4)(CF)in the SFC system,thereby inhibiting the precipitation of Ca_(2)Fe_(2)O_(5)(C_(2)F).In contrast to the Cao–Fe_(2)O_(3)(C–F)system,the addition of SiO_(2)does not alter the precipitation mechanisms of C_(2)F and CF.By further adding SiO_(2),the precipitation of Ca_(2)Sio_(4)(C_(2)S)significantly increases.Simultaneously,the Cao content in the liquid phase decreases.This leads to the crystallization process of the CF_(4)S(4 wt.%Sio_(2))system bypassing the precipitation of C_(2)F and directly forming CF and CaFe_(4)O_(7)(CF_(2)).In the case of the CF_(8)S(8 wt.%SiO_(2))system,the crystallization process skips the precipitation of C_(2)F and CF,directly yielding CF_(2).The crystallization process of both CF_(2)S(2 wt.%Sio_(2))and CF is similar,comprising two reaction stages.The Ozawa method was used to calculate the activation energy for the crystallization of C_(2)F and CF as-329 and-419 kJ/mol,respectively.Analysis using the Malek method reveals model functions for both stages.
基金the National Natural Science Foundation of China(Nos.51173170,21703207,21773216)the joint project from the Henan-Provincial and the China-National Natural Science Foundations(Project No.U2004208)
文摘Modulation of Si-O bonds under mild conditions has been a challenging issue in the field of material science,which is critical to manufacture highperformance silica-based optical and photonic devices.Herein,we introduce a nondestructive technique to achieve Si-O bond rearrangement,leading to plastic deformation and photoluminescence enhancement of amorphous silica nanoparticles using supercritical carbon dioxides in EtOH/H_(2)O solution under mild temperature.Specifically,plastic deformation is achieved by treating hollow mesoporous silica nanospheres using supercritical CO_(2)at 40°C under 20 MPa.Experimental and theoretical studies revealed the critical role of supercritical CO_(2)in the plastic deformation process,which can be intercalated into the hollow mesoporous silica nanospheres with anisotropic stresses and induces the rearrangement of Si-O bonds and transformation of ring structures.This work suggests a novel approach to engineer high-performance nano-silica glass components for numerous optical and photonic devices under mild condition.
基金supported by the National Key R&D program of China(2019YFA0706802)National Natural Science Foundation of China(52063029)+2 种基金Natural Science Basic Research Program of Shaanxi(2022JM-200,2021JQ-716)China Postdoctoral Science Foundation(2020M672269)Doctoral Research Program of Yan’an University(YDBK2019-02)
文摘Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially accessible internal spaces,and so forth.Dissimilar vip species(such as organic groups or metal nanoparticles)could be readily decorated onto the interfaces of the channels and pores,realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications.As adsorbents and catalysts,dendritic mesoporous silica nanoparticles-based materials have experienced nonignorable development in CO_(2)capture and catalytic conversion.This comprehensive review provides a critical survey on this pregnant subject,summarizing the designed construction of novel dendritic mesoporous silica nanoparticles-based materials,the involved chemical reactions(such as CO_(2)methanation,dry reforming of CH_(4)),the value-added chemicals from CO_(2)(such as cyclic carbonates,2-oxazolidinones,quinazoline-2,4(1H,3H)-diones),and so on.The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials(such as SBA-15 or MCM-41),and the corresponding reaction mechanisms have been thoroughly revealed.It is sincerely expected that the in-depth discussion could give materials scientists certain inspiration to design brand-new dendritic mesoporous silica nanoparticles-based materials with superior capabilities towards CO_(2)capture,utilization,and storage.
