Solid state lithium-ion batteries(SLIBs)have been considered as one of the most promising sustainable next-generation technologies for energy storage.However,the poor interfacial compatibility and low ion conductivity...Solid state lithium-ion batteries(SLIBs)have been considered as one of the most promising sustainable next-generation technologies for energy storage.However,the poor interfacial compatibility and low ion conductivity of solid electrolytes still remain a major challenge for SLIBs.Herein,a free-standing flexible solid polymer LA-PAM-PEO electrolyte is constructed through the electrospinning technology featuring with high Li+conductivity(6.1×10^(−4)S cm^(−1)),strong mechanical strength and high Li+migration num-ber(0.32),which breaks the restriction between ionic conductivity and mechanical strength in polymer solid electrolyte.The cross-linking between LA,PAM and PEO is verified to decrease the crystalline of PEO,thus increasing the Li+conductivity.Moreover,benefiting from the 3D network composed of in-terconnected nanofibers and the covalent bonds between LA,PAM and PEO,the mechanical strength of LA-PAM-PEO SPE was also effectively im proved.The LA-PAM-PEO SPE also delivers a high electrochemi-cal window(4.95 V),and low interface resistance(243.8).As a result,the Li/Li symmetrical cell with the LA-PAM-PEO displayed outstanding stability after 1000 h with the uniform Li deposition on the in-terface of Li electrode,in sharp contrast to the PEO SPE.In addition,the Li/LA-PAM-PEO SPE/LFP displays a discharge capacity of 135 mA h g^(−1)after 1000 cycles at the rate of 1 C,with a capacity retention of 93.5%.The proposed LA-PAM-PEO SPE thus opens new possibilities for the fabrication and engineering of solid-state Li-ion batteries.展开更多
Zirconium-based MOFs of the UiO family have attracted considerable attention due to their high thermal,chemical and mechanical stability. With the aim of further exploring the applications of zirconium-based UiO-66 in...Zirconium-based MOFs of the UiO family have attracted considerable attention due to their high thermal,chemical and mechanical stability. With the aim of further exploring the applications of zirconium-based UiO-66 in acid-catalyzed reactions and elucidating the effects of the defects in UiO-66 materials on their catalytic performances, in this work, a series of zirconium-containing UiO-66 samples were synthesized by varying the synthesis temperatures and BDC/Zr(terephthalic acid/ZrCl) ratios in the synthesis system.The synthesized UiO-66 samples were characterized by X-ray diffraction(XRD), Nadsorption-desorption,scanning electron microscopy(SEM), thermogravimetrical analysis(TGA), temperature-programmed desorption of NH(NH-TPD). Their catalytic performances were investigated in transesterification of tributyrin and soybean oil with methanol. The results showed that UiO-66 samples with different amounts of defects could be successfully prepared by varying the synthesis temperatures and/or the BDC/Zr ratios used in the synthesis system. The catalytic activities of the UiO-66 materials greatly depended on their linker defects and enhanced with the increase of the defect amount. The UiO-66 was an efficient catalyst for transesterification of tributyrin and soybean oil with methanol under mild reaction conditions and its catalytic activity was comparable to other solid acid catalysts reported in the literatures. The UiO-66 catalyst was relatively stable and could be reused.展开更多
Potassium-ion batteries(PIBs)are attractive for gridscale energy storage due to the abundant potassium resource and high energy density.The key to achieving high-performance and large-scale energy storage technology l...Potassium-ion batteries(PIBs)are attractive for gridscale energy storage due to the abundant potassium resource and high energy density.The key to achieving high-performance and large-scale energy storage technology lies in seeking eco-efficient synthetic processes to the design of suitable anode materials.Herein,a spherical sponge-like carbon superstructure(NCS)assembled by 2D nanosheets is rationally and efficiently designed for K+storage.The optimized NCS electrode exhibits an outstanding rate capability,high reversible specific capacity(250 mAh g^(−1) at 200 mA g^(−1) after 300 cycles),and promising cycling performance(205 mAh g^(−1) at 1000 mA g^(−1) after 2000 cycles).The superior performance can be attributed to the unique robust spherical structure and 3D electrical transfer network together with nitrogen-rich nanosheets.Moreover,the regulation of the nitrogen doping types and morphology of NCS-5 is also discussed in detail based on the experiments results and density functional theory calculations.This strategy for manipulating the structure and properties of 3D materials is expected to meet the grand challenges for advanced carbon materials as high-performance PIB anodes in practical applications.展开更多
Ordered mesoporous copper incorporated Al;O;（Cu/Al;O;） with high Cu dispersion were prepared by a facile solution combustion synthesis method using aluminum nitrate and copper nitrate as oxidants and urea as fuel. I...Ordered mesoporous copper incorporated Al;O;（Cu/Al;O;） with high Cu dispersion were prepared by a facile solution combustion synthesis method using aluminum nitrate and copper nitrate as oxidants and urea as fuel. It is a facile and green route to synthesize catalysts for dimethyl ether directly from syngas. Cu/Al;O;catalysts were characterized by XRD, N;adsorption–desorption, SEM-EDS, and H;-TPR.The results indicate that the catalysts obtain an ordered mesoporous structure and copper is homogenously dispersed. The mesoporous Cu/Al;O;catalysts were utilized as bifunctional catalysts in syngas to dimethyl ether reaction（STD）. The copper content affects the catalytic performance in STD reaction. The CO conversion and DME selectivity of Cu/Al;O;with 15% copper molar ratio achieve 52.9% and 66.1%,respectively. Moreover, the mesoporous Cu/Al;O;catalysts show excellent stability in STD reaction.展开更多
The hydrocarbon deposits have stimulated worldwide efforts to understand gas production from hydrate dissociation in hydrate reservoirs well. This paper deals with the potential of gas hydrates as a source of energy w...The hydrocarbon deposits have stimulated worldwide efforts to understand gas production from hydrate dissociation in hydrate reservoirs well. This paper deals with the potential of gas hydrates as a source of energy which is widely available in permafrost and oceanic sediments. It discusses methods for gas production from natural gas hydrates. Authors provide a detailed methodology used to model gas productivity recovery from hydrate reservoir well. The mathematical modelling of gas dissociation from hydrate reservoir as a tool for evaluating the potential of gas hydrates for natural gas production. The simulation results show that the process of natural gas production in a hydrate reservoir is a sensitive function of reservoir temperature and hydrate zone permeability. The model couples nth order decomposition kinetics with gas flow through porous media. The models provide a simple and useful tool for hydrate reservoir analysis.展开更多
The fabrication of Si_(3)N_(4) ceramics typically requires high temperatures(above 1700℃)and prolonged sintering time to achieve densification,resulting in high energy consumption and increased manufacturing costs.Mo...The fabrication of Si_(3)N_(4) ceramics typically requires high temperatures(above 1700℃)and prolonged sintering time to achieve densification,resulting in high energy consumption and increased manufacturing costs.Moreover,reports on the fabrication of dense Si_(3)N_(4) ceramics with good mechanical properties under MPa-level pressure and low temperatures are rare.In this work,we propose a low-temperature rapid spark plasma sintering strategy involving the introduction of fine-grainedβ-Si_(3)N_(4) powder with high lattice strain energy as an“additive”.Dense biphasic Si_(3)N_(4) ceramics,predominantlyα-Si_(3)N_(4),were successfully fabricated at a mechanical pressure of 200 MPa and a temperature of 1300℃,achieving a relative density of 97%.The application of high pressure promoted particle rearrangement and uniform liquid‒phase distribution,providing additional driving forces for sintering.The introduction ofβ-Si_(3)N_(4) seeds facilitated an in-situ solution–reprecipitation process,enabling rapid densification with a minimal liquid phase and without significant grain growth,resulting in nanometer-scale grains.The Si_(3)N_(4) sample prepared at 1350℃ exhibited a desirable combination of high hardness(18.5±0.3 GPa)and fracture toughness(6.7±0.2 MPa·m_(1/2)).The results demonstrate that by adjusting the sintering temperature and time,the phase composition and mechanical properties of the ceramics can be flexibly tailored.This work holds significant potential for industrial manufacturing and provides valuable insights into low-temperature strategies for ceramic fabrication.展开更多
Cellular immunity mediated by CD8+T cells plays an indispensable role in bacterial and viral clearance and cancers.However,persistent antigen stimulation of CD8+T cells leads to an exhausted or dysfunctional cellular ...Cellular immunity mediated by CD8+T cells plays an indispensable role in bacterial and viral clearance and cancers.However,persistent antigen stimulation of CD8+T cells leads to an exhausted or dysfunctional cellular state characterized by the loss of effector function and high expression of inhibitory receptors during chronic viral infection and in tumors.Numerous studies have shown that glycogen synthase kinase 3(GSK3)controls the function and development of immune cells,but whether GSK3 affects CD8+T cells is not clearly elucidated.Here,we demonstrate that mice with deletion of Gsk3αand Gsk3βin activated CD8+T cells(DKO)exhibited decreased CTL differentiation and effector function during acute and chronic viral infection.In addition,DKO mice failed to control tumor growth due to the upregulated expression of inhibitory receptors and augmented T-cell exhaustion in tumor-infiltrating CD8+T cells.Strikingly,anti-PD-1 immunotherapy substantially restored tumor rejection in DKO mice.Mechanistically,GSK3 regulates T-cell exhaustion by suppressing TCR-induced nuclear import of NFAT,thereby in turn dampening NFAT-mediated exhaustion-related gene expression,including TOX/TOX2 and PD-1.Thus,we uncovered the molecular mechanisms underlying GSK3 regulation of CTL differentiation and T-cell exhaustion in anti-tumor immune responses.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52072193 and U22A20131)the Shandong Provincial Natural Science Foundation(Nos.ZR2021JQ16 and ZR2023YQ040)+1 种基金the State Key Laboratory for Modification of Chemical Fibers and Polymer Materials(No.KF2217)the Shandong Provincial College Students’Innovation and Entrepreneurship Training Program(No.S202211065062).
文摘Solid state lithium-ion batteries(SLIBs)have been considered as one of the most promising sustainable next-generation technologies for energy storage.However,the poor interfacial compatibility and low ion conductivity of solid electrolytes still remain a major challenge for SLIBs.Herein,a free-standing flexible solid polymer LA-PAM-PEO electrolyte is constructed through the electrospinning technology featuring with high Li+conductivity(6.1×10^(−4)S cm^(−1)),strong mechanical strength and high Li+migration num-ber(0.32),which breaks the restriction between ionic conductivity and mechanical strength in polymer solid electrolyte.The cross-linking between LA,PAM and PEO is verified to decrease the crystalline of PEO,thus increasing the Li+conductivity.Moreover,benefiting from the 3D network composed of in-terconnected nanofibers and the covalent bonds between LA,PAM and PEO,the mechanical strength of LA-PAM-PEO SPE was also effectively im proved.The LA-PAM-PEO SPE also delivers a high electrochemi-cal window(4.95 V),and low interface resistance(243.8).As a result,the Li/Li symmetrical cell with the LA-PAM-PEO displayed outstanding stability after 1000 h with the uniform Li deposition on the in-terface of Li electrode,in sharp contrast to the PEO SPE.In addition,the Li/LA-PAM-PEO SPE/LFP displays a discharge capacity of 135 mA h g^(−1)after 1000 cycles at the rate of 1 C,with a capacity retention of 93.5%.The proposed LA-PAM-PEO SPE thus opens new possibilities for the fabrication and engineering of solid-state Li-ion batteries.
基金supported by the National Science Foundation of China (Nos. 20971095 and 21576177)Research Project Supported by Shanxi Scholarship Council of China (2013-047)
文摘Zirconium-based MOFs of the UiO family have attracted considerable attention due to their high thermal,chemical and mechanical stability. With the aim of further exploring the applications of zirconium-based UiO-66 in acid-catalyzed reactions and elucidating the effects of the defects in UiO-66 materials on their catalytic performances, in this work, a series of zirconium-containing UiO-66 samples were synthesized by varying the synthesis temperatures and BDC/Zr(terephthalic acid/ZrCl) ratios in the synthesis system.The synthesized UiO-66 samples were characterized by X-ray diffraction(XRD), Nadsorption-desorption,scanning electron microscopy(SEM), thermogravimetrical analysis(TGA), temperature-programmed desorption of NH(NH-TPD). Their catalytic performances were investigated in transesterification of tributyrin and soybean oil with methanol. The results showed that UiO-66 samples with different amounts of defects could be successfully prepared by varying the synthesis temperatures and/or the BDC/Zr ratios used in the synthesis system. The catalytic activities of the UiO-66 materials greatly depended on their linker defects and enhanced with the increase of the defect amount. The UiO-66 was an efficient catalyst for transesterification of tributyrin and soybean oil with methanol under mild reaction conditions and its catalytic activity was comparable to other solid acid catalysts reported in the literatures. The UiO-66 catalyst was relatively stable and could be reused.
基金the National Natural Science Foundation of China(Grant Nos.51772086,51572078,51872087,and 11605053)the Natural Science Foundation of Hunan Province(Grant No.2018JJ2038)the Hunan Provincial Natural Science Foundation of China(Grant No.2017JJ3052)。
文摘Potassium-ion batteries(PIBs)are attractive for gridscale energy storage due to the abundant potassium resource and high energy density.The key to achieving high-performance and large-scale energy storage technology lies in seeking eco-efficient synthetic processes to the design of suitable anode materials.Herein,a spherical sponge-like carbon superstructure(NCS)assembled by 2D nanosheets is rationally and efficiently designed for K+storage.The optimized NCS electrode exhibits an outstanding rate capability,high reversible specific capacity(250 mAh g^(−1) at 200 mA g^(−1) after 300 cycles),and promising cycling performance(205 mAh g^(−1) at 1000 mA g^(−1) after 2000 cycles).The superior performance can be attributed to the unique robust spherical structure and 3D electrical transfer network together with nitrogen-rich nanosheets.Moreover,the regulation of the nitrogen doping types and morphology of NCS-5 is also discussed in detail based on the experiments results and density functional theory calculations.This strategy for manipulating the structure and properties of 3D materials is expected to meet the grand challenges for advanced carbon materials as high-performance PIB anodes in practical applications.
基金supported by the National Natural Science Foundation of China(No.51,451,002,No.21,371,129)Shanxi Province Science Foundation for Youths(2,013,021,008-3)the joint funds of the National Natural Science Foundation of China–China Petroleum and Chemical Corporation(the state key program grant No.U1463209)
文摘Ordered mesoporous copper incorporated Al;O;（Cu/Al;O;） with high Cu dispersion were prepared by a facile solution combustion synthesis method using aluminum nitrate and copper nitrate as oxidants and urea as fuel. It is a facile and green route to synthesize catalysts for dimethyl ether directly from syngas. Cu/Al;O;catalysts were characterized by XRD, N;adsorption–desorption, SEM-EDS, and H;-TPR.The results indicate that the catalysts obtain an ordered mesoporous structure and copper is homogenously dispersed. The mesoporous Cu/Al;O;catalysts were utilized as bifunctional catalysts in syngas to dimethyl ether reaction（STD）. The copper content affects the catalytic performance in STD reaction. The CO conversion and DME selectivity of Cu/Al;O;with 15% copper molar ratio achieve 52.9% and 66.1%,respectively. Moreover, the mesoporous Cu/Al;O;catalysts show excellent stability in STD reaction.
文摘The hydrocarbon deposits have stimulated worldwide efforts to understand gas production from hydrate dissociation in hydrate reservoirs well. This paper deals with the potential of gas hydrates as a source of energy which is widely available in permafrost and oceanic sediments. It discusses methods for gas production from natural gas hydrates. Authors provide a detailed methodology used to model gas productivity recovery from hydrate reservoir well. The mathematical modelling of gas dissociation from hydrate reservoir as a tool for evaluating the potential of gas hydrates for natural gas production. The simulation results show that the process of natural gas production in a hydrate reservoir is a sensitive function of reservoir temperature and hydrate zone permeability. The model couples nth order decomposition kinetics with gas flow through porous media. The models provide a simple and useful tool for hydrate reservoir analysis.
基金supported by the National Natural Science Foundation of China(Nos.52425204,U20A20241,and U23A20566).
文摘The fabrication of Si_(3)N_(4) ceramics typically requires high temperatures(above 1700℃)and prolonged sintering time to achieve densification,resulting in high energy consumption and increased manufacturing costs.Moreover,reports on the fabrication of dense Si_(3)N_(4) ceramics with good mechanical properties under MPa-level pressure and low temperatures are rare.In this work,we propose a low-temperature rapid spark plasma sintering strategy involving the introduction of fine-grainedβ-Si_(3)N_(4) powder with high lattice strain energy as an“additive”.Dense biphasic Si_(3)N_(4) ceramics,predominantlyα-Si_(3)N_(4),were successfully fabricated at a mechanical pressure of 200 MPa and a temperature of 1300℃,achieving a relative density of 97%.The application of high pressure promoted particle rearrangement and uniform liquid‒phase distribution,providing additional driving forces for sintering.The introduction ofβ-Si_(3)N_(4) seeds facilitated an in-situ solution–reprecipitation process,enabling rapid densification with a minimal liquid phase and without significant grain growth,resulting in nanometer-scale grains.The Si_(3)N_(4) sample prepared at 1350℃ exhibited a desirable combination of high hardness(18.5±0.3 GPa)and fracture toughness(6.7±0.2 MPa·m_(1/2)).The results demonstrate that by adjusting the sintering temperature and time,the phase composition and mechanical properties of the ceramics can be flexibly tailored.This work holds significant potential for industrial manufacturing and provides valuable insights into low-temperature strategies for ceramic fabrication.
基金supported by the National Natural Science Foundation of China(31770953,81830047,and 81961138008 to CX and 32070877 to W-HL),1000 Young Talents Program of China(NX)the Fundamental Research Funds for the Central Universities of China-Xiamen University(20720170064 to CX).
文摘Cellular immunity mediated by CD8+T cells plays an indispensable role in bacterial and viral clearance and cancers.However,persistent antigen stimulation of CD8+T cells leads to an exhausted or dysfunctional cellular state characterized by the loss of effector function and high expression of inhibitory receptors during chronic viral infection and in tumors.Numerous studies have shown that glycogen synthase kinase 3(GSK3)controls the function and development of immune cells,but whether GSK3 affects CD8+T cells is not clearly elucidated.Here,we demonstrate that mice with deletion of Gsk3αand Gsk3βin activated CD8+T cells(DKO)exhibited decreased CTL differentiation and effector function during acute and chronic viral infection.In addition,DKO mice failed to control tumor growth due to the upregulated expression of inhibitory receptors and augmented T-cell exhaustion in tumor-infiltrating CD8+T cells.Strikingly,anti-PD-1 immunotherapy substantially restored tumor rejection in DKO mice.Mechanistically,GSK3 regulates T-cell exhaustion by suppressing TCR-induced nuclear import of NFAT,thereby in turn dampening NFAT-mediated exhaustion-related gene expression,including TOX/TOX2 and PD-1.Thus,we uncovered the molecular mechanisms underlying GSK3 regulation of CTL differentiation and T-cell exhaustion in anti-tumor immune responses.
