Several efficient analytical methods have been developed to solve the solid-state diffusion problem, for constant diffusion coefficient problems. However, these methods cannot be applied for concentration-dependent di...Several efficient analytical methods have been developed to solve the solid-state diffusion problem, for constant diffusion coefficient problems. However, these methods cannot be applied for concentration-dependent diffusion coefficient problems and numerical methods are used instead. Herein, grid-based numerical methods derived from the control volume discretization are presented to resolve the characteristic nonlinear system of partial differential equations. A novel hybrid backward Euler control volume (HBECV) method is presented which requires only one iteration to reach an implicit solution. The HBECV results are shown to be stable and accurate for a moderate number of grid points. The computational speed and accuracy of the HBECV, justify its use in battery simulations, in which the solid-state diffusion coefficient is a strong function of the concentration.展开更多
Diffusion bonding of refractory Nb–Si-based alloy was performed with Ni/Al and Ti/Al nanolayers under the condition of 1473 K/30 MPa/60 min.The NbSS/Nb5Si3 in situ composite with the nominal composition of Nb–22 Ti...Diffusion bonding of refractory Nb–Si-based alloy was performed with Ni/Al and Ti/Al nanolayers under the condition of 1473 K/30 MPa/60 min.The NbSS/Nb5Si3 in situ composite with the nominal composition of Nb–22 Ti–16 Si–3 Cr–3 Al–2 Hf was used as the parent material.The joint microstructures were examined by using a scanning electron microscope equipped with an X-ray energy dispersive spectrometer.Shear test was conducted for the bonded joints at room temperature.Within the joint bonded with Ni/Al multilayer,element diffusion occurred between the base metal and the nanolayer,with the reaction products of AlNb2+Ni3 Al,NiAl and AlNi2 Ti phases.The average shear strength was 182 MPa.While using Ti/Al multilayer,the interface mainly consisted of TiAl,(Ti,Nb)Al and(Ti,Nb)2 Al phases,and the corresponding joints exhibited an increased strength of 228 MPa.In this case,the fracture mainly took place in the TiAl phase and presented a typical brittle characteristic.展开更多
Multiphase multicomponent ultrahigh-temperature ceramics(UHTCs)hold great promise for achieving better ablation performance because of their broader structure and compositional tunability.However,the knowledge gap wit...Multiphase multicomponent ultrahigh-temperature ceramics(UHTCs)hold great promise for achieving better ablation performance because of their broader structure and compositional tunability.However,the knowledge gap with respect to ablation mechanisms hinders the design and optimization of these materials.Here,through studying the ablation behavior of a multiphase multicomponent carbide(i.e.,Hf–Zr–Ti–Ta–C)composed of Hf-rich carbide,Ta-rich carbide,and Ti-rich carbide phases,a thermodynamicdriven solid-state diffusion process between the constituent multicomponent phases during ablation was revealed.The solid-state diffusion of metal ions(mainly Zr and Ti)occurred among the oxidationaffected three-phase regions beneath the oxide layer,leading to the formation of Zr-and Ti-rich oxides.More importantly,the resulting Ta enrichment of the residual carbide phase enabled their thermodynamic stability to be sustained at a relatively high oxygen partial pressure,thus improving the oxidation resistance.Moreover,the coupling between the solid-state diffusion process and preferential oxidation behavior facilitated the in situ formation of a micron-sized Hf-rich oxide network,which effectively enhanced the mechanical properties of the oxide layer,thereby offering better protection against the scouring of hot high-speed flow.In summary,the synergistic effect of the solid-state diffusion process and preferential oxidation behavior optimized the ablation performance of the multiphase multicomponent carbide under extreme conditions.展开更多
This study shows that sulfide solid-state electrolytes,β-Li_(3)PS_(4)and Li_(6)PS_(5)Cl,are flammable solids.Both solid-state electrolytes release sulfur vapor in a dry,oxidizing environment at elevated temperature&l...This study shows that sulfide solid-state electrolytes,β-Li_(3)PS_(4)and Li_(6)PS_(5)Cl,are flammable solids.Both solid-state electrolytes release sulfur vapor in a dry,oxidizing environment at elevated temperature<300℃.Sulfur vapor is a highly flammable gas,which then auto-ignites to produce a flame.This behavior suggests that an O_(2)-S gas-gas reaction mechanism may contribute to all-solid-state battery thermal runaway.To improve all-solid-state battery safety,current work focuses on eliminating the O_(2)source by changing the cathode active material.The conclusion of this study suggests that all-solidstate battery safety can also be realized by the development of solid-state electrolytes with less susceptibility to sulfur volatilization.展开更多
A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,whic...A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,which is used for the scrambling,substitution and diffusion processes.The three-dimensional Fisher-Yates scrambling,S-box substitution and diffusion are employed for the first round of encryption.The chaotic sequence is adopted for secondary encryption to scramble the ciphertext obtained in the first round.Then,three-dimensional filter is applied to diffusion for further useful information hiding.The key to the algorithm is generated by the combination of hash value of plaintext image and the input parameters.It improves resisting ability of plaintext attacks.The security analysis shows that the algorithm is effective and efficient.It can resist common attacks.In addition,the good diffusion effect shows that the scheme can solve the differential attacks encountered in the transmission of medical images and has positive implications for future research.展开更多
The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of ...The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of interdiffusion coefficients(HitDIC)software at 1273−1373 K.The results show that the addition of Al,Cu,and Mn to CoCrFeNi high-entropy alloys promotes the diffusion of Co,Cr,and Fe atoms.The comparison of tracer diffusion coefficients indicates that there is no sluggish diffusion in tracer diffusion on the thermodynamic temperature scale for the present Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys.The linear relationship between diffusion entropy and activation energy reveals that the diffusion process of atoms is unaffected by an increase in the number of components as long as the crystal structure remains unchanged.展开更多
Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storag...Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storage systems.Among the numerous types of SSEs,inorganic oxide garnet-structured superionic conductors Li7La3Zr2O12(LLZO)crystallized with the cubic Iaˉ3d space group have received considerable attention owing to their highly advantageous intrinsic properties encompassing reasonable lithium-ion conductivity,wide electrochemical voltage window,high shear modulus,and excellent chemical stability with electrodes.However,no SSEs possess all the properties necessary for SSLBs,thus both the ionic conductivity at room temperature and stability in ambient air regarding cubic garnet-based electrolytes are still subject to further improvement.Hence,this review comprehensively covers the nine key structural factors affecting the ion conductivity of garnet-based electrolytes comprising Li concentration,Li vacancy concentration,Li carrier concentration and mobility,Li occupancy at available sites,lattice constant,triangle bottleneck size,oxygen vacancy defects,and Li-O bonding interactions.Furthermore,the general illustration of structures and fundamental features being crucial to chemical stability is examined,including Li concentration,Li-site occupation behavior,and Li-O bonding interactions.Insights into the composition-structure-property relations among cubic garnet-based oxide ionic conductors from the perspective of their crystal structures,revealing the potential compatibility conflicts between ionic transportation and chemical stability resulting from Li-O bonding interactions.We believe that this review will lay the foundation for future reasonable structural design of oxide-based or even other types of superionic conductors,thus assisting in promoting the rapid development of alternative green and sustainable technologies.展开更多
Composite solid electrolytes(CSEs)are considered among the most promising candidates for solid-state batteries.However,their practical application is hindered by low ionic conductivity and a limited lithium-ion transf...Composite solid electrolytes(CSEs)are considered among the most promising candidates for solid-state batteries.However,their practical application is hindered by low ionic conductivity and a limited lithium-ion transference number,primarily owing to the insufficient mobility of Li+.In this work,we design a heterojunc-tion nanoparticle composed of bimetallic zeolitic imidazolate frameworks(ZIFs)coupled with amorphous tita-nium oxide(TiO_(2)@Zn/Co–ZIF)as a filler to fabricate a composite solid-state electrolyte(PVZT).The amor-phous TiO_(2) coating facilitates salt dissociation through Lewis acid–base interactions with the anions of the lithium salt.Meanwhile,the Zn/Co–ZIF framework not only provides additional selective pathways for Li+transport but also effectively restricts anion migration through its confined pore size.The synergistic effect results in a high room-temperature ionic conductivity(8.8×10^(-4) S·cm^(-1))and a lithium-ion transference number of 0.47 for PVZT.A symmetrical cell using PVZT demonstrates stable Li+deposition/stripping for over 1100 h at a current density of 0.1 mA·cm^(-2).Additionally,a LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/Li full cell using PVZT retains 75.0%of its capacity after 1200 cycles at a 2 C rate.This work offers valuable insights into the design of func-tional fillers for CSEs with highly efficient ion transport.展开更多
Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited ...Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited research on molecular sequence diffusion models.The International Union of Pure and Applied Chemistry(IUPAC)names are more akin to chemical natural language than the simplified molecular input line entry system(SMILES)for organic compounds.In this work,we apply an IUPAC-guided conditional diffusion model to facilitate molecular editing from chemical natural language to chemical language(SMILES)and explore whether the pre-trained generative performance of diffusion models can be transferred to chemical natural language.We propose DiffIUPAC,a controllable molecular editing diffusion model that converts IUPAC names to SMILES strings.Evaluation results demonstrate that our model out-performs existing methods and successfully captures the semantic rules of both chemical languages.Chemical space and scaffold analysis show that the model can generate similar compounds with diverse scaffolds within the specified constraints.Additionally,to illustrate the model’s applicability in drug design,we conducted case studies in functional group editing,analogue design and linker design.展开更多
The excellent irradiation resistance,high strength and plasticity exhibited by high-entropy alloys(HEAs)make it candidate for engin-eering applications.Diffusion bonding of Al_(0.3)CoCrFeNi single-phase HEAs was carri...The excellent irradiation resistance,high strength and plasticity exhibited by high-entropy alloys(HEAs)make it candidate for engin-eering applications.Diffusion bonding of Al_(0.3)CoCrFeNi single-phase HEAs was carried out using electric-assisted diffusion bonding(EADB),and the effect of bonding temperature on the evolution of the interfacial microstructure and the mechanical properties was investigated.The results indicate that as the bonding temperature increases,the pores at the interface gradually decrease in size and undergo closure.The electric current significantly promotes the pore closure mechanism dominated by plastic deformation at the diffusion interface and promotes the recrystallisation behavior at the interface,and the fracture mode changes from intergranular fracture at the interface to jagged fracture along the grains spanning the weld parent material.Due to the activation effect of EADB,higher-strength diffusion bonding of high-entropy alloys can be achieved at the same temperature compared with the conventional hot-pressure diffusion bonding(HPDB)process.展开更多
This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydra...This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S paste.The results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.展开更多
The search for safer next-generation lithium-ion batteries(LIBs)has driven significant research on non-toxic,non-flammable solid electrolytes.However,their electrochemical performance often falls short.This work prese...The search for safer next-generation lithium-ion batteries(LIBs)has driven significant research on non-toxic,non-flammable solid electrolytes.However,their electrochemical performance often falls short.This work presents a simple,one-step photopolymerization process for synthesizing biphasic liquid–solid ionogel electrolytes using acrylic acid monomer and P_(111i4)FSI ionic liquid.We investigated the impact of lithium salt concentration and temperature on ion diffusion,particularly lithium-ion(Li^(+))mobility,within these ionogels.Pulsed-field gradient nuclear magnetic resonance(PFG-NMR)revealed enhanced Li^(+)diffusion in the acrylic acid(AA)-based ionogels compared to their non-confined ionic liquid counterparts.Remarkably,Li^(+)diffusion remained favorable in the ionogels regardless of salt concentration.These AA-based ionogels demonstrate very good ionic conductivity(>1 mS cm^(-1) at room temperature)and a wide electrochemical window(up to 5.3 V vs Li^(+)/Li^(0)).These findings suggest significant promise for AA-based ionogels as polymer solid electrolytes in future solid-state battery applications.展开更多
Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular st...Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules.展开更多
文摘Several efficient analytical methods have been developed to solve the solid-state diffusion problem, for constant diffusion coefficient problems. However, these methods cannot be applied for concentration-dependent diffusion coefficient problems and numerical methods are used instead. Herein, grid-based numerical methods derived from the control volume discretization are presented to resolve the characteristic nonlinear system of partial differential equations. A novel hybrid backward Euler control volume (HBECV) method is presented which requires only one iteration to reach an implicit solution. The HBECV results are shown to be stable and accurate for a moderate number of grid points. The computational speed and accuracy of the HBECV, justify its use in battery simulations, in which the solid-state diffusion coefficient is a strong function of the concentration.
基金financially supported by the Beijing Municipal Science & Technology Commission (No. Z171100002217048)the National Natural Science Foundation of China (No. 51705489)
文摘Diffusion bonding of refractory Nb–Si-based alloy was performed with Ni/Al and Ti/Al nanolayers under the condition of 1473 K/30 MPa/60 min.The NbSS/Nb5Si3 in situ composite with the nominal composition of Nb–22 Ti–16 Si–3 Cr–3 Al–2 Hf was used as the parent material.The joint microstructures were examined by using a scanning electron microscope equipped with an X-ray energy dispersive spectrometer.Shear test was conducted for the bonded joints at room temperature.Within the joint bonded with Ni/Al multilayer,element diffusion occurred between the base metal and the nanolayer,with the reaction products of AlNb2+Ni3 Al,NiAl and AlNi2 Ti phases.The average shear strength was 182 MPa.While using Ti/Al multilayer,the interface mainly consisted of TiAl,(Ti,Nb)Al and(Ti,Nb)2 Al phases,and the corresponding joints exhibited an increased strength of 228 MPa.In this case,the fracture mainly took place in the TiAl phase and presented a typical brittle characteristic.
基金supported by the Early Career Talent Development Program of Jiangxi Province(No.20244BCE52008)the Key R&D Program of Jiangxi Province,China(No.20224BBE51044)+1 种基金the Program Jiangxi Provincial Natural Science Foundation(No.20232BAB214021)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2024JC-YBQN-0467).
文摘Multiphase multicomponent ultrahigh-temperature ceramics(UHTCs)hold great promise for achieving better ablation performance because of their broader structure and compositional tunability.However,the knowledge gap with respect to ablation mechanisms hinders the design and optimization of these materials.Here,through studying the ablation behavior of a multiphase multicomponent carbide(i.e.,Hf–Zr–Ti–Ta–C)composed of Hf-rich carbide,Ta-rich carbide,and Ti-rich carbide phases,a thermodynamicdriven solid-state diffusion process between the constituent multicomponent phases during ablation was revealed.The solid-state diffusion of metal ions(mainly Zr and Ti)occurred among the oxidationaffected three-phase regions beneath the oxide layer,leading to the formation of Zr-and Ti-rich oxides.More importantly,the resulting Ta enrichment of the residual carbide phase enabled their thermodynamic stability to be sustained at a relatively high oxygen partial pressure,thus improving the oxidation resistance.Moreover,the coupling between the solid-state diffusion process and preferential oxidation behavior facilitated the in situ formation of a micron-sized Hf-rich oxide network,which effectively enhanced the mechanical properties of the oxide layer,thereby offering better protection against the scouring of hot high-speed flow.In summary,the synergistic effect of the solid-state diffusion process and preferential oxidation behavior optimized the ablation performance of the multiphase multicomponent carbide under extreme conditions.
文摘This study shows that sulfide solid-state electrolytes,β-Li_(3)PS_(4)and Li_(6)PS_(5)Cl,are flammable solids.Both solid-state electrolytes release sulfur vapor in a dry,oxidizing environment at elevated temperature<300℃.Sulfur vapor is a highly flammable gas,which then auto-ignites to produce a flame.This behavior suggests that an O_(2)-S gas-gas reaction mechanism may contribute to all-solid-state battery thermal runaway.To improve all-solid-state battery safety,current work focuses on eliminating the O_(2)source by changing the cathode active material.The conclusion of this study suggests that all-solidstate battery safety can also be realized by the development of solid-state electrolytes with less susceptibility to sulfur volatilization.
文摘A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,which is used for the scrambling,substitution and diffusion processes.The three-dimensional Fisher-Yates scrambling,S-box substitution and diffusion are employed for the first round of encryption.The chaotic sequence is adopted for secondary encryption to scramble the ciphertext obtained in the first round.Then,three-dimensional filter is applied to diffusion for further useful information hiding.The key to the algorithm is generated by the combination of hash value of plaintext image and the input parameters.It improves resisting ability of plaintext attacks.The security analysis shows that the algorithm is effective and efficient.It can resist common attacks.In addition,the good diffusion effect shows that the scheme can solve the differential attacks encountered in the transmission of medical images and has positive implications for future research.
基金supported by the National Natural Science Foundation of China(No.52374372)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.23KJB430042)+3 种基金the Jiangsu Province Large Scientific Instruments Open Sharing Autonomous Research Filing Project,China(No.TC2023A037)the Yangzhou City−Yangzhou University Cooperation Foundation,China(No.YZ2022183)High-end Talent Support Program of Yangzhou University,China,Qinglan Project of Yangzhou University,ChinaLvyangjinfeng Talent program of Yangzhou,China.
文摘The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of interdiffusion coefficients(HitDIC)software at 1273−1373 K.The results show that the addition of Al,Cu,and Mn to CoCrFeNi high-entropy alloys promotes the diffusion of Co,Cr,and Fe atoms.The comparison of tracer diffusion coefficients indicates that there is no sluggish diffusion in tracer diffusion on the thermodynamic temperature scale for the present Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys.The linear relationship between diffusion entropy and activation energy reveals that the diffusion process of atoms is unaffected by an increase in the number of components as long as the crystal structure remains unchanged.
基金supported by the National Natural Science Foundation of China(Nos.22171102 and 22090044)the National Key R&D Program of China(Nos.2021YFF0500502 and 2023YFA1506304)+2 种基金the Jilin Province Science and Technology Development Plan(No.20230101024JC)the"Medicine+X"crossinnovation team of Bethune Medical Department of Jilin University"Leading the Charge with Open Competition"construction project(No.2022JBGS04)the Jilin University Graduate Training Office(Nos.2021JGZ08 and 2022YJSJIP20).
文摘Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storage systems.Among the numerous types of SSEs,inorganic oxide garnet-structured superionic conductors Li7La3Zr2O12(LLZO)crystallized with the cubic Iaˉ3d space group have received considerable attention owing to their highly advantageous intrinsic properties encompassing reasonable lithium-ion conductivity,wide electrochemical voltage window,high shear modulus,and excellent chemical stability with electrodes.However,no SSEs possess all the properties necessary for SSLBs,thus both the ionic conductivity at room temperature and stability in ambient air regarding cubic garnet-based electrolytes are still subject to further improvement.Hence,this review comprehensively covers the nine key structural factors affecting the ion conductivity of garnet-based electrolytes comprising Li concentration,Li vacancy concentration,Li carrier concentration and mobility,Li occupancy at available sites,lattice constant,triangle bottleneck size,oxygen vacancy defects,and Li-O bonding interactions.Furthermore,the general illustration of structures and fundamental features being crucial to chemical stability is examined,including Li concentration,Li-site occupation behavior,and Li-O bonding interactions.Insights into the composition-structure-property relations among cubic garnet-based oxide ionic conductors from the perspective of their crystal structures,revealing the potential compatibility conflicts between ionic transportation and chemical stability resulting from Li-O bonding interactions.We believe that this review will lay the foundation for future reasonable structural design of oxide-based or even other types of superionic conductors,thus assisting in promoting the rapid development of alternative green and sustainable technologies.
基金supported by National Science Fund for Distinguished Young Scholars(Grant No.52325206)National Key Research and Development Program of China(Grant No.2021YFF0500600)+3 种基金National Natural Science Foundation of China(Grant Nos.U2001220 and 52203298)Shenzhen Technical Plan Project(Grant Nos.RCJC20200714114436091,JCYJ20220530143012027,JCYJ20220818101003008,and JCYJ20220818101003007)Tsinghua Shenzhen International Graduate School-Shenzhen Pengrui Young Faculty Program of Shenzhen Pengrui Foundation(Grant No.SZPR2023006)Shenzhen Science and Technology Program(Grant No.WDZC20231126160733001).
文摘Composite solid electrolytes(CSEs)are considered among the most promising candidates for solid-state batteries.However,their practical application is hindered by low ionic conductivity and a limited lithium-ion transference number,primarily owing to the insufficient mobility of Li+.In this work,we design a heterojunc-tion nanoparticle composed of bimetallic zeolitic imidazolate frameworks(ZIFs)coupled with amorphous tita-nium oxide(TiO_(2)@Zn/Co–ZIF)as a filler to fabricate a composite solid-state electrolyte(PVZT).The amor-phous TiO_(2) coating facilitates salt dissociation through Lewis acid–base interactions with the anions of the lithium salt.Meanwhile,the Zn/Co–ZIF framework not only provides additional selective pathways for Li+transport but also effectively restricts anion migration through its confined pore size.The synergistic effect results in a high room-temperature ionic conductivity(8.8×10^(-4) S·cm^(-1))and a lithium-ion transference number of 0.47 for PVZT.A symmetrical cell using PVZT demonstrates stable Li+deposition/stripping for over 1100 h at a current density of 0.1 mA·cm^(-2).Additionally,a LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/Li full cell using PVZT retains 75.0%of its capacity after 1200 cycles at a 2 C rate.This work offers valuable insights into the design of func-tional fillers for CSEs with highly efficient ion transport.
基金supported by the Yonsei University graduate school Department of Integrative Biotechnology.
文摘Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited research on molecular sequence diffusion models.The International Union of Pure and Applied Chemistry(IUPAC)names are more akin to chemical natural language than the simplified molecular input line entry system(SMILES)for organic compounds.In this work,we apply an IUPAC-guided conditional diffusion model to facilitate molecular editing from chemical natural language to chemical language(SMILES)and explore whether the pre-trained generative performance of diffusion models can be transferred to chemical natural language.We propose DiffIUPAC,a controllable molecular editing diffusion model that converts IUPAC names to SMILES strings.Evaluation results demonstrate that our model out-performs existing methods and successfully captures the semantic rules of both chemical languages.Chemical space and scaffold analysis show that the model can generate similar compounds with diverse scaffolds within the specified constraints.Additionally,to illustrate the model’s applicability in drug design,we conducted case studies in functional group editing,analogue design and linker design.
基金support from National Natural Science Foundation of China(NSFC,Grant numbers U22A20185,U21A20128,52175302 and 52305353)Aeronautical Science Foundation(ASFC-20230036077001)Fundamental Research Funds for the Central Universities(2022FRFK060009,HIT.DZI1.2023012).
文摘The excellent irradiation resistance,high strength and plasticity exhibited by high-entropy alloys(HEAs)make it candidate for engin-eering applications.Diffusion bonding of Al_(0.3)CoCrFeNi single-phase HEAs was carried out using electric-assisted diffusion bonding(EADB),and the effect of bonding temperature on the evolution of the interfacial microstructure and the mechanical properties was investigated.The results indicate that as the bonding temperature increases,the pores at the interface gradually decrease in size and undergo closure.The electric current significantly promotes the pore closure mechanism dominated by plastic deformation at the diffusion interface and promotes the recrystallisation behavior at the interface,and the fracture mode changes from intergranular fracture at the interface to jagged fracture along the grains spanning the weld parent material.Due to the activation effect of EADB,higher-strength diffusion bonding of high-entropy alloys can be achieved at the same temperature compared with the conventional hot-pressure diffusion bonding(HPDB)process.
基金Funded by the Natural Science Foundation of Jiangsu Province(No.BK20241529)China Postdoctoral Science Foundation(No.2024M750736)。
文摘This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S paste.The results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.
基金funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Actions COFUND—Grant Agreement No:945357.
文摘The search for safer next-generation lithium-ion batteries(LIBs)has driven significant research on non-toxic,non-flammable solid electrolytes.However,their electrochemical performance often falls short.This work presents a simple,one-step photopolymerization process for synthesizing biphasic liquid–solid ionogel electrolytes using acrylic acid monomer and P_(111i4)FSI ionic liquid.We investigated the impact of lithium salt concentration and temperature on ion diffusion,particularly lithium-ion(Li^(+))mobility,within these ionogels.Pulsed-field gradient nuclear magnetic resonance(PFG-NMR)revealed enhanced Li^(+)diffusion in the acrylic acid(AA)-based ionogels compared to their non-confined ionic liquid counterparts.Remarkably,Li^(+)diffusion remained favorable in the ionogels regardless of salt concentration.These AA-based ionogels demonstrate very good ionic conductivity(>1 mS cm^(-1) at room temperature)and a wide electrochemical window(up to 5.3 V vs Li^(+)/Li^(0)).These findings suggest significant promise for AA-based ionogels as polymer solid electrolytes in future solid-state battery applications.
文摘Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules.
