Background:The aim of this study was to analyze the bi-directional causal relation-ship between lipid profile and characteristics related to muscle atrophy by using a bi-directional Mendelian randomization(MR)analysis...Background:The aim of this study was to analyze the bi-directional causal relation-ship between lipid profile and characteristics related to muscle atrophy by using a bi-directional Mendelian randomization(MR)analysis.Methods:The appendicular lean mass(ALM),whole body fat-free mass(WBFFM)and trunk fat-free mass(TFFM)were used as genome-wide association study(GWAS)data for evaluating muscle mass;the usual walking pace(UWP)and low grip strength(LGS)were used as GWAS data for evaluating muscle strength;and the triglycerides(TG),total cholesterol(TC),high density lipoprotein cholesterol(HDL),low density lipo-protein cholesterol(LDL),apolipoprotein A-1(Apo A-1),and apolipoprotein B(Apo B)were used as GWAS data for evaluating lipid profile.For specific investigations,we mainly employed inverse variance weighting for causal estimation and MR-Egger for pleiotropy analysis.Results:MR results showed that the lipid profile predicted by genetic variants was negatively correlated with muscle mass,positively correlated with UWP,and was not causally correlated with LGS.On the other hand,the muscle mass predicted by genetic variants was negatively correlated with lipid profile,the UWP predicted by genetic variants was mainly positively correlated with lipid profile,while the LGS pre-dicted by genetic variants had no relevant causal relationship with lipid profile.Conclusions:Findings of this MR analysis suggest that hyperlipidemia may affect muscle mass and lead to muscle atrophy,but has no significant effect on muscle strength.On the other hand,increased muscle mass may reduce the incidence of dyslipidemia.展开更多
Zirconium metal-organic frameworks(Zr-MOFs)represent the most promising candidates among MOFs for industrial utilizations owing to their high porosity and excellent stability.However,the efficient synthesis of Zr-MOFs...Zirconium metal-organic frameworks(Zr-MOFs)represent the most promising candidates among MOFs for industrial utilizations owing to their high porosity and excellent stability.However,the efficient synthesis of Zr-MOFs combining with continuous production,high productivity and good product quality still remains a critical issue for practical applications.Herein,we report an efficient method of synthesizing a series of Zr-MOFs through a microdroplet flow reaction,which is more accommodate the requirements of industrial production.Four types of Zr-based MOFs with different ligands and topologies(MOF-801,MOF-804,DUT-67 and MOF-808)were produced as a pure phase of high quality crystalline with uniform morphologies.Furthermore,this series of Zr-MOFs were obtained in a continuous way and at a space-time yield(STY)highly up to 367.2 kg m-3 d-1.These MOFs exhibit the similar pore structure and thermal stability with that prepared from conventional solvothermal synthesis.CO2 sorption studies on these MOFs demonstrate that the hydroxyl groups on ligand can render MOFs with high CO2/N2 selectivity.展开更多
Background:Osteoarthritis(OA)is a long-term degenerative joint disease worsen-ing over time.Aging and chondrocyte senescence contribute to OA progression.MicroRNAs have been confirmed to regulate different cellular pr...Background:Osteoarthritis(OA)is a long-term degenerative joint disease worsen-ing over time.Aging and chondrocyte senescence contribute to OA progression.MicroRNAs have been confirmed to regulate different cellular processes.They con-tribute to OA pathology and may help to identify novel biomarkers and therapies for OA.Methods:This study used bioinformatics and experimental investigations to analyze and validate differentially expressed miRNAs in OA that might affect chondrocyte apoptosis and senescence.Results:miR-6779 was found to be significantly down-regulated in OA.Seventy-six of the predicted and miR-6779 targeted genes and the OA-associated disease genes overlapped,and these were enriched in cell proliferation,cell apoptosis,and cell cycle.miR-6779 overexpression remarkably attenuated IL-1βeffects on chon-drocytes by reducing MMP3 and MMP13 levels,promoting cell apoptosis,suppress-ing cell senescence,and increasing caspase-3,caspase-9 and reducing P16 and P21 levels.miR-6779 targeted inhibition of X-linked inhibitor of apoptosis protein(XIAP)expression.XIAP knockdown partially improved IL-1β-induced chondrocyte senes-cence and dysfunction.Lastly,when co-transfected with a miR-6779 agomir,the XIAP overexpression vector partially attenuated the effects of miR-6779 overexpression on chondrocytes;miR-6779 improved IL-1β-induced senescence and dysfunction in chondrocytes through targeting XIAP.Conclusion:miR-6779 is down-regulated,and XIAP is up-regulated in OA cartilage and IL-1β-treated chondrocytes.miR-6779 inhibits XIAP expression,thereby promot-ing senescent chondrocyte cell apoptosis and reducing chondrocyte senescence and ECM loss through XIAP.展开更多
Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels.However,there remains a major challenge for achieving the on-demand shapi...Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels.However,there remains a major challenge for achieving the on-demand shaping of carbon aerogels with tailored micro-nano structural textures and geometric features.Herein,a facile extrusion 3D printing strategy has been proposed for fabricating CNT-assembled carbon(CNT/C)aerogel nanocomposites through the extrusion printing of pseudoplastic carbomer-based inks,in which the stable dispersion of CNT nanofibers has been achieved relying on the high viscosity of carbomer microgels.After extrusion printing,the chemical solidification through polymerizing RF sols enables 3D-printed aerogel nanocomposites to display high shape fidelity in macroscopic geometries.Benefiting from the micro-nano scale assembly of CNT nanofiber networks and carbon nanoparticle networks in composite phases,3D-printed CNT/C aerogels exhibit enhanced mechanical strength(fracture strength,0.79 MPa)and typical porous structure characteristics,including low density(0.220 g cm^(-3)),high surface area(298.4 m^(2)g^(-1)),and concentrated pore diameter distribution(~32.8nm).More importantly,CNT nanofibers provide an efficient electron transport pathway,imparting 3D-printed CNT/C aerogel composites with a high electrical conductivity of 1.49 S cm^(-1).Our work would offer feasible guidelines for the design and fabrication of shape-dominated functional materials by additive manufacturing.展开更多
Lotus(Nelumbo nucifera Gaertn.)is an economically important perennial aquatic herb plant in China.Presently,viral diseases caused by Cucumber mosaic virus(CMV)and Dasheen mosaic virus(DsMV)are detected in lotus.In thi...Lotus(Nelumbo nucifera Gaertn.)is an economically important perennial aquatic herb plant in China.Presently,viral diseases caused by Cucumber mosaic virus(CMV)and Dasheen mosaic virus(DsMV)are detected in lotus.In this study,the putatively novel badnaviruses from lotus plants(LBVs)were identified using next-generation sequencing of siRNAs and conventional Sanger sequencing based on the RT/RNase H coding region sequences.Lotus plants infected by LBVs harbored virus quasispecies.A unique recombination event of LBVs was found in a single lotus plant.Sap inoculation showed that LBVs could actively replicate in the lotus plants,but without a wide host range.The field survey of 43 lotus plants in Jiangsu Province showed a prevalence of 62.8%for LBVs,confirming that it is widely distributed in Jiangsu Province of China.展开更多
As an emerging zero-dimensional nano crystalline porous material,porous organic cages(POCs)with soluble properties in organic solvents,are promising candidates as molecular fillers in mixed matrix membranes(MMMs).The ...As an emerging zero-dimensional nano crystalline porous material,porous organic cages(POCs)with soluble properties in organic solvents,are promising candidates as molecular fillers in mixed matrix membranes(MMMs).The pore structure of POCs should be adjusted to trigger efficient gas separation performance,and the interaction between filler and matrix should be optimized.In this work,ionic liquid(IL)was introduced into the molecular fillers of CC3,to construct the IL@CC3/PIM-1 membrane to effectively separate CO_(2) from CH_(4).The advantages of doping IL include:(1)narrowing the cavity size of POCs from 4.4 to 3.9Åto enhance the diffusion selectivity,(2)strengthening the CO_(2) solubility to heighten the gas permeability,and(3)improving the compatibility between filler and matrix to upgrade membrane stability.After the optimization of the membrane composite,the IL@CC3/PIM-1-10%membrane possesses the CO_(2) permeability of 7868 Barrer and the CO_(2)/CH_(4) selectivity of 73.4,which compared to the CC3/PIM-1-10%membrane,improved by 15.9%and 106.2%,respectively.Furthermore,the membrane has maintained a stable separation performance at varied temperatures and pressures during the long-term test.The proposed method offers an efficient way to improve the performance of POCs-based MMMs in gas separation.展开更多
Conversion/alloying anode materials exhibiting high K storage capacities suffer from large volume variations and unstable electrode/electrolyte interfaces upon cycling.Herein,taking SnS/reduced graphene oxide(SnS/rGO)...Conversion/alloying anode materials exhibiting high K storage capacities suffer from large volume variations and unstable electrode/electrolyte interfaces upon cycling.Herein,taking SnS/reduced graphene oxide(SnS/rGO)anodes as an example,the electrochemical performance of SnS/rGO could significantly be improved via employing potassium bis(fluorosulfonyl)imide(KFSI)salt in electrolytes and ultrathin TiO_(2) coating.KF-rich inorganic layer was demonstrated to help form robust SEI layer,which could suppress the side reactions to increase the Coulombic efficiency.The formed potassiated K_(x)TiO_(2) coating layer was constructed to boost charge transfer capability and K-ion diffusion kinetics.The as-prepared SnS/rGO@TiO_(2)-20 electrode in KFSI electrolyte delivers the high CE of 99.1%and 424 mAh·g^(−1) after 200 cycles with an ultrahigh capacity retention of 98.5%.展开更多
二氧化硅气凝胶由于其低导热率在隔热应用方面具有巨大的潜力.然而,它们通常具有较差的机械性能,需要在保持低热导率的同时增强机械性能.本研究以商业化气相二氧化硅和甲基三甲氧基硅烷为硅源,并以水和乙醇为溶剂形成浆料.基于此,二氧...二氧化硅气凝胶由于其低导热率在隔热应用方面具有巨大的潜力.然而,它们通常具有较差的机械性能,需要在保持低热导率的同时增强机械性能.本研究以商业化气相二氧化硅和甲基三甲氧基硅烷为硅源,并以水和乙醇为溶剂形成浆料.基于此,二氧化硅气凝胶块体(SAMs)可通过常压干燥进行制备,且无需额外的表面改性或溶剂置换.制备的SAMs保持了典型的纳米孔结构,具有低密度(0.24 g cm^(-3))、收缩率(4%)和热导率(0.046 W m^(-1)K^(-1)).通过辊压将浆料浸渍到纤维毡中,并通过浆料热固化和常压干燥制备出二氧化硅气凝胶毡(SABs).制备的SABs具有良好的柔韧性和机械性能,便于安装和隔热应用,并显著减少了生产周期和成本.此外,基于SAMs的纳米孔结构和低收缩率,通过调控遮光剂的粒径和质量分数进一步降低了SABs的高温热导率,优化后的SABs在800℃的热导率低至0.054 W m^(-1)K^(-1).展开更多
High performance thermal insulation materials are urgently demanded for energy saving and thermal protection applications.Organic aerogels are considered as promising and highly efficient thermal insulation materials,...High performance thermal insulation materials are urgently demanded for energy saving and thermal protection applications.Organic aerogels are considered as promising and highly efficient thermal insulation materials,but high shrinkage has been a major obstacle to limit their development and application.Herein,by a co-polymerization of formaldehyde(F)and benzoxazine prepolymers,polybenzoxazine with increased crosslink density and thus enhanced gel strength was formed,leading to low shrinkage polybenzoxazine(PBOF)aerogels with hierarchical micro/nanostructures.The hierarchical porous nanoskeleton of PBOF aerogels,composed of stacked thick-united spherical nanoparticles,was formed due to the different solubility of the reactants in N,N-dimethylformamide and F aqueous solution.Benefitting from the low shrinkage(13.22%,exceeding 60%reduction),the PBOF aerogels exhibit a low thermal conductivity of 0.0397 W m^(−1)K^(−1)at room temperature and outstanding thermal protection ability at high temperature.A 13 mm thick sample could resist a butane flame of 1300°C for 90 s,and the hand was not burn when touching the back.This strategy enables PBOF aerogels with a new perspective for their applications in civil and military fields.展开更多
Resistant starch(RS),as a natural plant active ingredient,had been widely used in preventing or alleviating colitis due to its anti-digestive and anti-inflammatory properties.In this study,starch was extracted from lo...Resistant starch(RS),as a natural plant active ingredient,had been widely used in preventing or alleviating colitis due to its anti-digestive and anti-inflammatory properties.In this study,starch was extracted from lotus root(LS),and RS was prepared using physical(autoclaving)and biotechnological(pullulanase debranching)methods.Lotus root resistant starch type III(LRS)was then purified using amyloglucosidase and porcine pancreaticα-amylase.A comprehensive analysis was conducted on the structural and physicochemical characteristics and in vivo anti-inflammatory activities of LRS.The findings revealed that autoclaving and enzymatic treatment increased the solubility and thermal stability of the starch,reduced the swelling power,and changed the crystalline type from CA-type to B-type.More importantly,the amylose content and molecular order of LRS were increased,which promoted the formation of crystalline structures and significantly increased the antidigestive ability of starch.Animal experiments showed that LRS was effective in alleviating colitis.After the intervention of LRS,the levels of IL-10,T-AOC,SOD and CAT were significantly increased,while the levels of IL-6,TNF-αand MDA were significantly decreased in the colon of mice.In addition,LRS was able to improve gut microflora dysbiosis as well as promote the production of SCFAs.These results suggested that LRS had a great potential in the field of functional foods.展开更多
基金Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2021A1515220030Hunan Provincial Clinical Medical Technology Innovation Guiding Project,Grant/Award Number:2020SK53307+2 种基金Hunan Provincial Health Commission,Grant/Award Number:20201902Natural Science Foundation of Hunan Province,Grant/Award Number:2020JJ8043Project of Hunan Provincial Health,Grant/Award Number:c2019133。
文摘Background:The aim of this study was to analyze the bi-directional causal relation-ship between lipid profile and characteristics related to muscle atrophy by using a bi-directional Mendelian randomization(MR)analysis.Methods:The appendicular lean mass(ALM),whole body fat-free mass(WBFFM)and trunk fat-free mass(TFFM)were used as genome-wide association study(GWAS)data for evaluating muscle mass;the usual walking pace(UWP)and low grip strength(LGS)were used as GWAS data for evaluating muscle strength;and the triglycerides(TG),total cholesterol(TC),high density lipoprotein cholesterol(HDL),low density lipo-protein cholesterol(LDL),apolipoprotein A-1(Apo A-1),and apolipoprotein B(Apo B)were used as GWAS data for evaluating lipid profile.For specific investigations,we mainly employed inverse variance weighting for causal estimation and MR-Egger for pleiotropy analysis.Results:MR results showed that the lipid profile predicted by genetic variants was negatively correlated with muscle mass,positively correlated with UWP,and was not causally correlated with LGS.On the other hand,the muscle mass predicted by genetic variants was negatively correlated with lipid profile,the UWP predicted by genetic variants was mainly positively correlated with lipid profile,while the LGS pre-dicted by genetic variants had no relevant causal relationship with lipid profile.Conclusions:Findings of this MR analysis suggest that hyperlipidemia may affect muscle mass and lead to muscle atrophy,but has no significant effect on muscle strength.On the other hand,increased muscle mass may reduce the incidence of dyslipidemia.
基金supported by grants from the National Natural Science Foundation of China(Nos.21401215,21473254)the Special Project Fund of"Taishan Scholars"of Shandong Province(No.ts201511017)
文摘Zirconium metal-organic frameworks(Zr-MOFs)represent the most promising candidates among MOFs for industrial utilizations owing to their high porosity and excellent stability.However,the efficient synthesis of Zr-MOFs combining with continuous production,high productivity and good product quality still remains a critical issue for practical applications.Herein,we report an efficient method of synthesizing a series of Zr-MOFs through a microdroplet flow reaction,which is more accommodate the requirements of industrial production.Four types of Zr-based MOFs with different ligands and topologies(MOF-801,MOF-804,DUT-67 and MOF-808)were produced as a pure phase of high quality crystalline with uniform morphologies.Furthermore,this series of Zr-MOFs were obtained in a continuous way and at a space-time yield(STY)highly up to 367.2 kg m-3 d-1.These MOFs exhibit the similar pore structure and thermal stability with that prepared from conventional solvothermal synthesis.CO2 sorption studies on these MOFs demonstrate that the hydroxyl groups on ligand can render MOFs with high CO2/N2 selectivity.
基金Natural Science Foundation of Changsha city,China,Grant/Award Number:kq2403166Hunan Provincial Clinical Medical Technology Innovation Guiding Project,Grant/Award Number:2020SK53307+4 种基金Basic Public Welfare Research projects of Wenzhou Science and Technology Bureau,Grant/Award Number:Y20240087Natural Science Foundation of Hunan Province,Grant/Award Number:2020JJ8043Start-up Funding for Talented Scientific Research of the First Affiliated Hospital of Wenzhou Medical University,Grant/Award Number:2023QD026Key Project of Hunan Provincial Health Commission,Grant/Award Number:20201902 and C2019133National Natural Science Foundation of China,Grant/Award Number:82472495。
文摘Background:Osteoarthritis(OA)is a long-term degenerative joint disease worsen-ing over time.Aging and chondrocyte senescence contribute to OA progression.MicroRNAs have been confirmed to regulate different cellular processes.They con-tribute to OA pathology and may help to identify novel biomarkers and therapies for OA.Methods:This study used bioinformatics and experimental investigations to analyze and validate differentially expressed miRNAs in OA that might affect chondrocyte apoptosis and senescence.Results:miR-6779 was found to be significantly down-regulated in OA.Seventy-six of the predicted and miR-6779 targeted genes and the OA-associated disease genes overlapped,and these were enriched in cell proliferation,cell apoptosis,and cell cycle.miR-6779 overexpression remarkably attenuated IL-1βeffects on chon-drocytes by reducing MMP3 and MMP13 levels,promoting cell apoptosis,suppress-ing cell senescence,and increasing caspase-3,caspase-9 and reducing P16 and P21 levels.miR-6779 targeted inhibition of X-linked inhibitor of apoptosis protein(XIAP)expression.XIAP knockdown partially improved IL-1β-induced chondrocyte senes-cence and dysfunction.Lastly,when co-transfected with a miR-6779 agomir,the XIAP overexpression vector partially attenuated the effects of miR-6779 overexpression on chondrocytes;miR-6779 improved IL-1β-induced senescence and dysfunction in chondrocytes through targeting XIAP.Conclusion:miR-6779 is down-regulated,and XIAP is up-regulated in OA cartilage and IL-1β-treated chondrocytes.miR-6779 inhibits XIAP expression,thereby promot-ing senescent chondrocyte cell apoptosis and reducing chondrocyte senescence and ECM loss through XIAP.
基金supported by the Hunan Provincial Natural Science Foundation of China (Grant no.2023JJ30632)National Key R&D Program (Grant no.2022YFC2204403)Key R&D Program of Hunan Province (Grant no.2022GK2027)。
文摘Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels.However,there remains a major challenge for achieving the on-demand shaping of carbon aerogels with tailored micro-nano structural textures and geometric features.Herein,a facile extrusion 3D printing strategy has been proposed for fabricating CNT-assembled carbon(CNT/C)aerogel nanocomposites through the extrusion printing of pseudoplastic carbomer-based inks,in which the stable dispersion of CNT nanofibers has been achieved relying on the high viscosity of carbomer microgels.After extrusion printing,the chemical solidification through polymerizing RF sols enables 3D-printed aerogel nanocomposites to display high shape fidelity in macroscopic geometries.Benefiting from the micro-nano scale assembly of CNT nanofiber networks and carbon nanoparticle networks in composite phases,3D-printed CNT/C aerogels exhibit enhanced mechanical strength(fracture strength,0.79 MPa)and typical porous structure characteristics,including low density(0.220 g cm^(-3)),high surface area(298.4 m^(2)g^(-1)),and concentrated pore diameter distribution(~32.8nm).More importantly,CNT nanofibers provide an efficient electron transport pathway,imparting 3D-printed CNT/C aerogel composites with a high electrical conductivity of 1.49 S cm^(-1).Our work would offer feasible guidelines for the design and fabrication of shape-dominated functional materials by additive manufacturing.
基金Key project at central government level:The ability establishment of sustainable use for valuable Chinese medicine resources(Grant No.2060302)the National Natural Science Foundation of China(Grant No.31601604)China Agriculture Research System(Grant No.CARS-24).
文摘Lotus(Nelumbo nucifera Gaertn.)is an economically important perennial aquatic herb plant in China.Presently,viral diseases caused by Cucumber mosaic virus(CMV)and Dasheen mosaic virus(DsMV)are detected in lotus.In this study,the putatively novel badnaviruses from lotus plants(LBVs)were identified using next-generation sequencing of siRNAs and conventional Sanger sequencing based on the RT/RNase H coding region sequences.Lotus plants infected by LBVs harbored virus quasispecies.A unique recombination event of LBVs was found in a single lotus plant.Sap inoculation showed that LBVs could actively replicate in the lotus plants,but without a wide host range.The field survey of 43 lotus plants in Jiangsu Province showed a prevalence of 62.8%for LBVs,confirming that it is widely distributed in Jiangsu Province of China.
基金supported by the National Natural Science Foundation of China(Nos.21875285,22171288,22005340)the Key Research and Development Projects of Shandong Province(No.2019JZZY010331)+2 种基金the Natural Science Foundation of Shandong Province(Nos.ZR2020MB017,ZR2022MB009)the Fundamental Research Funds for the Central Universities(No.23CX07004A)the Outstanding Youth Science Fund Projects of Shandong Province(Nos.2022HWYQ-070,ZR2022YQ15).
文摘As an emerging zero-dimensional nano crystalline porous material,porous organic cages(POCs)with soluble properties in organic solvents,are promising candidates as molecular fillers in mixed matrix membranes(MMMs).The pore structure of POCs should be adjusted to trigger efficient gas separation performance,and the interaction between filler and matrix should be optimized.In this work,ionic liquid(IL)was introduced into the molecular fillers of CC3,to construct the IL@CC3/PIM-1 membrane to effectively separate CO_(2) from CH_(4).The advantages of doping IL include:(1)narrowing the cavity size of POCs from 4.4 to 3.9Åto enhance the diffusion selectivity,(2)strengthening the CO_(2) solubility to heighten the gas permeability,and(3)improving the compatibility between filler and matrix to upgrade membrane stability.After the optimization of the membrane composite,the IL@CC3/PIM-1-10%membrane possesses the CO_(2) permeability of 7868 Barrer and the CO_(2)/CH_(4) selectivity of 73.4,which compared to the CC3/PIM-1-10%membrane,improved by 15.9%and 106.2%,respectively.Furthermore,the membrane has maintained a stable separation performance at varied temperatures and pressures during the long-term test.The proposed method offers an efficient way to improve the performance of POCs-based MMMs in gas separation.
基金the Fundamental Research Funds for the Central Universities(Nos.19CX05002A and 17CX02039A)the Project of Science and Technology of Chongzuo City(FA2020008)+2 种基金the Key Research and Development Plan of Shandong Province(2018GGX102017)the New Faculty Start-up Funding in the China University of Petroleum(East China)(YJ201601023)the Special Project Fund of“Taishan Scholars”of Shandong Province(ts201511017).
文摘Conversion/alloying anode materials exhibiting high K storage capacities suffer from large volume variations and unstable electrode/electrolyte interfaces upon cycling.Herein,taking SnS/reduced graphene oxide(SnS/rGO)anodes as an example,the electrochemical performance of SnS/rGO could significantly be improved via employing potassium bis(fluorosulfonyl)imide(KFSI)salt in electrolytes and ultrathin TiO_(2) coating.KF-rich inorganic layer was demonstrated to help form robust SEI layer,which could suppress the side reactions to increase the Coulombic efficiency.The formed potassiated K_(x)TiO_(2) coating layer was constructed to boost charge transfer capability and K-ion diffusion kinetics.The as-prepared SnS/rGO@TiO_(2)-20 electrode in KFSI electrolyte delivers the high CE of 99.1%and 424 mAh·g^(−1) after 200 cycles with an ultrahigh capacity retention of 98.5%.
基金supported by Hunan Provincial Natural Science Foundation of China (2023JJ30632)the Key R & D Program of Hunan Province (2022GK2027)。
文摘二氧化硅气凝胶由于其低导热率在隔热应用方面具有巨大的潜力.然而,它们通常具有较差的机械性能,需要在保持低热导率的同时增强机械性能.本研究以商业化气相二氧化硅和甲基三甲氧基硅烷为硅源,并以水和乙醇为溶剂形成浆料.基于此,二氧化硅气凝胶块体(SAMs)可通过常压干燥进行制备,且无需额外的表面改性或溶剂置换.制备的SAMs保持了典型的纳米孔结构,具有低密度(0.24 g cm^(-3))、收缩率(4%)和热导率(0.046 W m^(-1)K^(-1)).通过辊压将浆料浸渍到纤维毡中,并通过浆料热固化和常压干燥制备出二氧化硅气凝胶毡(SABs).制备的SABs具有良好的柔韧性和机械性能,便于安装和隔热应用,并显著减少了生产周期和成本.此外,基于SAMs的纳米孔结构和低收缩率,通过调控遮光剂的粒径和质量分数进一步降低了SABs的高温热导率,优化后的SABs在800℃的热导率低至0.054 W m^(-1)K^(-1).
基金supported by the National Key Research and Development Program of China(2022YFC2204403)the Key Research and Development Plan of Hunan(2022GK2027)the Natural Science Foundation of Hunan(2023JJ30632).
文摘High performance thermal insulation materials are urgently demanded for energy saving and thermal protection applications.Organic aerogels are considered as promising and highly efficient thermal insulation materials,but high shrinkage has been a major obstacle to limit their development and application.Herein,by a co-polymerization of formaldehyde(F)and benzoxazine prepolymers,polybenzoxazine with increased crosslink density and thus enhanced gel strength was formed,leading to low shrinkage polybenzoxazine(PBOF)aerogels with hierarchical micro/nanostructures.The hierarchical porous nanoskeleton of PBOF aerogels,composed of stacked thick-united spherical nanoparticles,was formed due to the different solubility of the reactants in N,N-dimethylformamide and F aqueous solution.Benefitting from the low shrinkage(13.22%,exceeding 60%reduction),the PBOF aerogels exhibit a low thermal conductivity of 0.0397 W m^(−1)K^(−1)at room temperature and outstanding thermal protection ability at high temperature.A 13 mm thick sample could resist a butane flame of 1300°C for 90 s,and the hand was not burn when touching the back.This strategy enables PBOF aerogels with a new perspective for their applications in civil and military fields.
基金supported by National Natural Science Foundation of China(No.31871803).
文摘Resistant starch(RS),as a natural plant active ingredient,had been widely used in preventing or alleviating colitis due to its anti-digestive and anti-inflammatory properties.In this study,starch was extracted from lotus root(LS),and RS was prepared using physical(autoclaving)and biotechnological(pullulanase debranching)methods.Lotus root resistant starch type III(LRS)was then purified using amyloglucosidase and porcine pancreaticα-amylase.A comprehensive analysis was conducted on the structural and physicochemical characteristics and in vivo anti-inflammatory activities of LRS.The findings revealed that autoclaving and enzymatic treatment increased the solubility and thermal stability of the starch,reduced the swelling power,and changed the crystalline type from CA-type to B-type.More importantly,the amylose content and molecular order of LRS were increased,which promoted the formation of crystalline structures and significantly increased the antidigestive ability of starch.Animal experiments showed that LRS was effective in alleviating colitis.After the intervention of LRS,the levels of IL-10,T-AOC,SOD and CAT were significantly increased,while the levels of IL-6,TNF-αand MDA were significantly decreased in the colon of mice.In addition,LRS was able to improve gut microflora dysbiosis as well as promote the production of SCFAs.These results suggested that LRS had a great potential in the field of functional foods.
