The title compound C18H18N4OS has been synthesized by the reaction of 3-(2-hydroxy- benzyl)-4-amino-(1H)-1,2,4-triazole-5-thione with 4-isopropylbenzaldehyde in ethanol and characterized by IR, ^1H NMR spectra and...The title compound C18H18N4OS has been synthesized by the reaction of 3-(2-hydroxy- benzyl)-4-amino-(1H)-1,2,4-triazole-5-thione with 4-isopropylbenzaldehyde in ethanol and characterized by IR, ^1H NMR spectra and elemental analysis. Its structure was determined by X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 11.605(2), b = 7.401(1), c = 20.339(2) A, β= 103.05(2)°, V= 1701.8(4) A^3, Z = 4, Mr = 338.42,μ = 0.202 mm^-1, Dc = 1.321 g/cm^3 and F(000) = 712. The structure was solved by direct methods and refined to R = 0.0428 and wR = 0.1069. Due to the intramolecular O-H…N hydrogen bond and π-π stacking interactions between the benzene (C(1)~C(6)) and triazole rings, the two planes are essentially coplanar. Their biological activities have been measured, showing this type of compound has certain antibacterial activity for Staphylococous aureus and Bacillus subtilis. Based on the quantum chemistry calculation at the RHF/6-31G level, the frontier orbitals and electrostatic potential of the title compound were also discussed.展开更多
All-solid-state batteries(ASSBs)with solid-state electrolytes and lithium-metal anodes have been regarded as a promis-ing battery technology to alleviate range anxiety and address safety issues due to their high energ...All-solid-state batteries(ASSBs)with solid-state electrolytes and lithium-metal anodes have been regarded as a promis-ing battery technology to alleviate range anxiety and address safety issues due to their high energy density and high safety.Understanding the fundamental physical and chemical science of ASSBs is of great importance to battery development.To confirm and supplement experimental study,theoretical computation provides a powerful approach to probe the thermody-namic and kinetic behavior of battery materials and their interfaces,resulting in the design of better batteries.In this review,we assess recent progress in the theoretical computations of solid electrolytes and the interfaces between the electrodes and electrolytes of ASSBs.We review the role of theoretical computation in studying the following:ion transport mechanisms,grain boundaries,phase stability,chemical and electrochemical stability,mechanical properties,design strategies and high-throughput screening of inorganic solid electrolytes,mechanical stability,space-charge layers,interface buffer layers and dendrite growth at electrode/electrolyte interfaces.Finally,we provide perspectives on the shortcomings,challenges and opportunities of theoretical computation in regard to ASSBs.展开更多
An extensive set of measurements in 2-D turbulent mixing layer, wake and jet flow by the hot-wire technique and data sampling are presented. The measured quantities, i. e. the mean velocity, the turbulence intensity, ...An extensive set of measurements in 2-D turbulent mixing layer, wake and jet flow by the hot-wire technique and data sampling are presented. The measured quantities, i. e. the mean velocity, the turbulence intensity, the Reynolds stress and higher-order correlations of the fluctuating velocity in the self-preserving region of the above free shear flows are compared with the computational results based on Zhou's theory for the shear turbulence of in- compressible fluid. The experimental and computational results are in good agreement.展开更多
In the realm of large-scale power system energy storage,sodium-based batteries represent a cost-effective post-lithium energy storage technology,making inorganic solid-state sodium batteries(ISSSB)a critical branch of...In the realm of large-scale power system energy storage,sodium-based batteries represent a cost-effective post-lithium energy storage technology,making inorganic solid-state sodium batteries(ISSSB)a critical branch of this development.Inorganic solid-state electrolytes(ISSEs)are the core components of sodium batteries;however,they face significant challenges such as insufficient ionic conductivity,interfacial instability,and dendrite growth,all of which severely hinder practical application.This review critically assesses experimental protocols and theoretical frameworks related to mainstream ISSEs and systematizes optimization strategies aimed at overcoming these challenges.Leveraging integrated insights from both experimental and computational studies,the review first categorizes and summarizes the primary types of ISSEs,namely oxide-,sulfide-,and halide-based electrolytes.It then details interfacial optimization strategies focused on addressing three core interfacial issues:ion transport barriers resulting from mechanical incompatibility,side reactions stemming from electrochemical mismatch,and dendrite formation.Finally,the review advocates prioritizing in-depth research that integrates experimental and theoretical approaches to establish a closed-loop methodology encompassing predictive design,multiscale investigation,mechanistic exploration,and high-throughput automated experimentation,with feedback-driven refinement.This work serves as a comprehensive reference and systematic roadmap for future research on solid-state electrolytes(SSEs).展开更多
The specific crystalline form of a compound remarkably affects its physicochemical properties.Therefore,a detailed analysis of the structural features and intermolecular interactions of a multi-component crystal is fe...The specific crystalline form of a compound remarkably affects its physicochemical properties.Therefore,a detailed analysis of the structural features and intermolecular interactions of a multi-component crystal is feasible to understand the relationships among the structure,physicochemical properties and the formation mechanism.In the present study,three novel cocrystal salt solvates of rhein and berberine were reported for the first time.Various solid characterizations and theoretical computations based on density functional theory(DFT)were carried out to demonstrate the intermolecular interactions.The theoretical computation shows that the strongest interaction existed between berberine cation and rhein anion,and the electrostatic interaction play a dominant role.However,no salt bond was observed between them.Further intrinsic dissolution rate analysis in water shows that the monohydrate exhibits 17 times enhancement in comparison with rhein.The rhein and berberine combined in ionic state in cocrystal salt is the main reason for the solubility improvement.This paper suggests that the interactions between the different components can be visualized and qualitatively and quantitatively analyzed by theoretical computation,which is helpful to understand the relationship between stereochemical structure and physicochemical properties of multi-component complex.展开更多
Electroreduction of nitrite to ammonia(NO_(2)RR)is recognized as an appealing method for achieving renewable NH_(3)production and waste NO_(2)^(-)removal.Herein,monodispersed W-doped ZnO(W_(1-)ZnO)is develo ped as an ...Electroreduction of nitrite to ammonia(NO_(2)RR)is recognized as an appealing method for achieving renewable NH_(3)production and waste NO_(2)^(-)removal.Herein,monodispersed W-doped ZnO(W_(1-)ZnO)is develo ped as an efficient NO_(2)RR catalyst.Theoretical simulations and in situ spectroscopic measurements unravel that the enhanced NO_(2)RR property of W_(1)-ZnO originates from the creation of active W_(1)-Zn dinuclear sites to selectively activate NO_(2)^(-)and enhance the protonation energetics of NO_(2)^(-)to-NH_(3)pathway,whilst repelling the competing H_(2)evolution.Strikingly,W_(1)-ZnO equipped in flow cell shows an impressive NO_(2)RR performa nce with NH_(3)yield rate of 970μmol h^(-1)cm^(-2)and NH_(3)-Faradaic efficiency of 94.5%.展开更多
Electrochemical reduction of NO_(2)-to NH_(3)(NO_(2)-RR) is recognized as an appealing approach for achieving renewable NH_(3)synthesis and waste NO_(2)-removal.Herein,we report isolated Bi alloyed Ru (Bi1Ru) as an ef...Electrochemical reduction of NO_(2)-to NH_(3)(NO_(2)-RR) is recognized as an appealing approach for achieving renewable NH_(3)synthesis and waste NO_(2)-removal.Herein,we report isolated Bi alloyed Ru (Bi1Ru) as an efficient NO_(2)-RR catalyst.Theoretical calculations and in situ electrochemical measurements reveal the creation of Bi1-Ru dual sites which can remarkably promote NO_(2)-activation and suppress proton adsorption,while accelerating the NO_(2)-RR protonation energetics to render a high NO_(2)--to-NH_(3)conversion efficiency.Remarkably,Bi1Ru assembled in a flow cell delivers an NH_(3)yield rate of 1901.4μmol h^(-1)cm^(-2)and an NH_(3)-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA cm^(-2).This study offers new perspectives for designing and constructing p-block single-atom alloys as robust and high-current-density NO_(2)-RR catalysts toward the ammonia electrosynthesis.展开更多
OX_(2)(X=halogen)molecules was studied theoretically.Calculation results show that delocalizedπ_(3)^(6) bonds exist in their electronic structures and O atoms adopt the sp^(2) type of hybridization,which violates the...OX_(2)(X=halogen)molecules was studied theoretically.Calculation results show that delocalizedπ_(3)^(6) bonds exist in their electronic structures and O atoms adopt the sp^(2) type of hybridization,which violates the prediction of the valence shell electron pair repulsion theory of sp^(3) type.Delocalization stabilization energy is proposed to measure the contribution of delocalizedπ_(3)^(6) bond to energy decrease and proves to bring extra-stability to the molecule.These phenomena can be summarized as a kind of coordinating effect.展开更多
NASICON (Na superionic conductor)-type cathode materials for sodium-ion batteries (SIBs) have attractedextensive attention due to their mechanically robust three-dimensional (3D) framework, which has sufficient opench...NASICON (Na superionic conductor)-type cathode materials for sodium-ion batteries (SIBs) have attractedextensive attention due to their mechanically robust three-dimensional (3D) framework, which has sufficient openchannels for fast Na^(+) transportation. However, they usually suffer from inferior electronic conductivity and lowcapacity, which severely limit their practical applications. To solve these issues, we need to deeply understand thestructural evolution, redox mechanisms, and electrode/electrolyte interface reactions during cycling. Recently,rapid developments in synchrotron X-ray techniques, neutron-based resources, magnetic resonance, as well asoptical and electron microscopy have brought numerous opportunities to gain deep insights into the Na-storagebehaviors of NASICON cathodes. In this review, we summarize the detection principles of advanced characterization techniques used with typical NASICON-structured cathode materials for SIBs. The special focus is on bothoperando and ex situ techniques, which help to investigate the relationships among phase, composition, andvalence variations within electrochemical responses. Fresh electrochemical measurements and theoretical computations are also included to reveal the kinetics and energy-storage mechanisms of electrodes upon charge/discharge. Finally, we describe potential new developments in NASICON-cathodes with optimized SIB systems,foreseeing a bright future for them, achievable through the rational application of advanced diagnostic methods.展开更多
Electrochemical converting NO_(2)^(-)into NH_(3)(NO_(2)RR)holds an enormous prospect to attain efficient NH_(3) electrosynthesis and polluted NO_(2)^(-)mitigation.Herein,we report single-atom Co alloyed Ru(Co_(1)Ru)as...Electrochemical converting NO_(2)^(-)into NH_(3)(NO_(2)RR)holds an enormous prospect to attain efficient NH_(3) electrosynthesis and polluted NO_(2)^(-)mitigation.Herein,we report single-atom Co alloyed Ru(Co_(1)Ru)as an efficient and durable NO_(2)RR catalyst.Extensive experimental and theoretical investigations reveal that single-atom Co alloying of Ru enables the construction of Co_(1)-Ru heteronuclear active sites to synergistically promote NO_(2)^(-)activation/hydrogenation while suppressing the competitive H_(2) evolution,rendering the greatly enhanced activity and selectivity of Co_(1)Ru towards the NO_(2)RR.Consequently,Co_(1)Ru assembled within a flow cell exhibits an impressive NH_(3) yield rate of 2379.2μmol·h^(-1)·cm^(-2) with an NH_(3)-Faradaic efficiency of 92%at a high current density of 415.9 mA·cm^(-2),which is among the highest NO_(2)RR performances reported to date.展开更多
Electrochemical NO_(2)~--to-NH_(3) conversion(NO_(2)RR) offers a green route to NH_(3) electrosynthesis, while developing efficient NO_(2)RR catalysis systems at high current densities remains a grand challenge. Herei...Electrochemical NO_(2)~--to-NH_(3) conversion(NO_(2)RR) offers a green route to NH_(3) electrosynthesis, while developing efficient NO_(2)RR catalysis systems at high current densities remains a grand challenge. Herein, we report an efficient Zr-NiO catalyst with atomically dispersed Zr-dopants incorporated in NiO lattice, delivering the exceptional NO_(2)RR performance with industriallevel current density(>0.2 A cm^(-2)). In situ spectroscopic measurements and theoretical simulations reveal the construction of ZrNi frustrated Lewis acid-base pairs(FLPs) on Zr-Ni O, which can substantially increase the number of absorbed nitrite(NO_(2)~-),promote the activation and protonation of NO_(2)~- and concurrently hamper the H coverage, boosting the activity and selectivity of Zr-NiO towards the NO_(2)RR. Remarkably, Zr-NiO exhibits the exceptional performance in a flow cell with high Faradaic efficiency for NH_(3) of 94.0% and NH_(3)yield rate of 1,394.1 μmol h^(-1)cm^(-2) at an industrial-level current density of 228.2 m A cm^(-2),placing it among the best NO_(2)RR electrocatalysts for NH_(3) production.展开更多
Energy materials play an important role in renewable and green energy technologies.The exploration of new materials,including nanomaterials,is important for breaking through the current bottlenecks of energy density a...Energy materials play an important role in renewable and green energy technologies.The exploration of new materials,including nanomaterials,is important for breaking through the current bottlenecks of energy density and charging rates.However,traditional theoretical computational methods face the dilemma of long research cycles.Machine learning methods have in recent years shown considerable potential for accelerating research efforts.However,most approaches are limited to specific properties of particular devices.In this paper,we propose a forward prediction and screening framework for functional materials,which includes database selection,attributes,descriptors,machine learning models,and prediction and screening.Based on the Materials Project database,auto-encoding methods are employed to generate Coulomb matrices as the input to train the convolutional neural networks,which finally screen 12 lithium-ion,6 zinc-ion,and 8 aluminum-ion battery cathode materials satisfying the criteria from 4,300 materials.The results show that the proposed framework can predict material performance well toward rapid initial screening.The proposed framework can provide a specific and complete working process reference for energy materials design work,contributing to the theoretical foundation for the design of core industrial software for materials engineering.展开更多
Only from the primary structures of peptides,a new set of descriptors called the molecular electro-negativity edge-distance vector(VMED)was proposed and applied to describing and characterizing the molecular structure...Only from the primary structures of peptides,a new set of descriptors called the molecular electro-negativity edge-distance vector(VMED)was proposed and applied to describing and characterizing the molecular structures of oligopeptides and polypeptides,based on the electronegativity of each atom or electronic charge index(ECI)of atomic clusters and the bonding distance between atom-pairs.Here,the molecular structures of antigenic polypeptides were well expressed in order to propose the auto-mated technique for the computerized identification of helper T lymphocyte(Th)epitopes.Furthermore,a modified MED vector was proposed from the primary structures of polypeptides,based on the ECI and the relative bonding distance of the fundamental skeleton groups.The side-chains of each amino acid were here treated as a pseudo-atom.The developed VMED was easy to calculate and able to work.Some quantitative model was established for 28 immunogenic or antigenic polypeptides(AGPP)with 14(1―14)Ad and 14 other restricted activities assigned as"1"(+)and"0"(-),respectively.The latter comprised 6 Ab(15-20),3 Ak(21-23),2 Ek(24-26),2 H-2k(27 and 28)restricted sequences.Good results were obtained with 90%correct classification(only 2 wrong ones for 20 training samples)and 100%correct prediction(none wrong for 8 testing samples);while con-trastively 100%correct classification(none wrong for 20 training samples)and 88%correct classification(1 wrong for 8 testing samples).Both stochastic samplings and cross valida-tions were performed to demonstrate good performance.The described method may also be suitable for estimation and prediction of classes I and II for major histocompatibility an-tigen(MHC)epitope of human.It will be useful in immune identification and recognition of pro-teins and genes and in the design and devel-opment of subunit vaccines.Several quantitative structure activity relationship(QSAR)models were developed for various oligopeptides and polypeptides including 58 dipeptides and 31 pentapeptides with angiotensin converting enzyme(ACE)inhibition by multiple linear regression(MLR)method.In order to explain the ability to characterize molecular structure of polypeptides,a molecular modeling investigation on QSAR was performed for functional prediction of polypeptide sequences with anti-genic activity and heptapeptide sequences with tachykinin activity through quantitative se-quence-activity models(QSAMs)by the molecular electronegativity edge-distance vector(VMED).The results showed that VMED exhibited both excellent structural selectivity and good activity prediction.Moreover,the results showed that VMED behaved quite well for both QSAR and QSAM of poly-and oli-gopeptides,which exhibited both good estimation ability and prediction power,equal to or better than those reported in the previous references.Finally,a preliminary conclusion was drwan:both classical and modified MED vectors were very useful structural descriptors.Some suggestions were proposed for further studies on QSAR/QSAM of proteins in various fields.展开更多
基金This work was supported by the Natural Science Foundation of Zhejiang Province (No. M203115) and Scientific Research Fund of Zhejiang Provincial Education Department (No. 20050057)
文摘The title compound C18H18N4OS has been synthesized by the reaction of 3-(2-hydroxy- benzyl)-4-amino-(1H)-1,2,4-triazole-5-thione with 4-isopropylbenzaldehyde in ethanol and characterized by IR, ^1H NMR spectra and elemental analysis. Its structure was determined by X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 11.605(2), b = 7.401(1), c = 20.339(2) A, β= 103.05(2)°, V= 1701.8(4) A^3, Z = 4, Mr = 338.42,μ = 0.202 mm^-1, Dc = 1.321 g/cm^3 and F(000) = 712. The structure was solved by direct methods and refined to R = 0.0428 and wR = 0.1069. Due to the intramolecular O-H…N hydrogen bond and π-π stacking interactions between the benzene (C(1)~C(6)) and triazole rings, the two planes are essentially coplanar. Their biological activities have been measured, showing this type of compound has certain antibacterial activity for Staphylococous aureus and Bacillus subtilis. Based on the quantum chemistry calculation at the RHF/6-31G level, the frontier orbitals and electrostatic potential of the title compound were also discussed.
基金supported by the Key-Area Research and Development Program of Guangdong Province(2020B090919005)the National Natural Science Foundation of China(21975274)+3 种基金Shandong Provincial Natural Science Foundation(ZR2020KE032)the Youth Innovation Promotion Association of CAS(2021210)the Shandong Energy Institute(SEI)(SEI I202117)the Taishan Scholars of Shandong Province(ts201511063).
文摘All-solid-state batteries(ASSBs)with solid-state electrolytes and lithium-metal anodes have been regarded as a promis-ing battery technology to alleviate range anxiety and address safety issues due to their high energy density and high safety.Understanding the fundamental physical and chemical science of ASSBs is of great importance to battery development.To confirm and supplement experimental study,theoretical computation provides a powerful approach to probe the thermody-namic and kinetic behavior of battery materials and their interfaces,resulting in the design of better batteries.In this review,we assess recent progress in the theoretical computations of solid electrolytes and the interfaces between the electrodes and electrolytes of ASSBs.We review the role of theoretical computation in studying the following:ion transport mechanisms,grain boundaries,phase stability,chemical and electrochemical stability,mechanical properties,design strategies and high-throughput screening of inorganic solid electrolytes,mechanical stability,space-charge layers,interface buffer layers and dendrite growth at electrode/electrolyte interfaces.Finally,we provide perspectives on the shortcomings,challenges and opportunities of theoretical computation in regard to ASSBs.
文摘An extensive set of measurements in 2-D turbulent mixing layer, wake and jet flow by the hot-wire technique and data sampling are presented. The measured quantities, i. e. the mean velocity, the turbulence intensity, the Reynolds stress and higher-order correlations of the fluctuating velocity in the self-preserving region of the above free shear flows are compared with the computational results based on Zhou's theory for the shear turbulence of in- compressible fluid. The experimental and computational results are in good agreement.
基金the National Natural Science Foundation of China (52076076, 52006065)Fundamental Research Funds for Central Universities (2025JC003)Beijing Municipal Natural Science Foundation (3242022)
文摘In the realm of large-scale power system energy storage,sodium-based batteries represent a cost-effective post-lithium energy storage technology,making inorganic solid-state sodium batteries(ISSSB)a critical branch of this development.Inorganic solid-state electrolytes(ISSEs)are the core components of sodium batteries;however,they face significant challenges such as insufficient ionic conductivity,interfacial instability,and dendrite growth,all of which severely hinder practical application.This review critically assesses experimental protocols and theoretical frameworks related to mainstream ISSEs and systematizes optimization strategies aimed at overcoming these challenges.Leveraging integrated insights from both experimental and computational studies,the review first categorizes and summarizes the primary types of ISSEs,namely oxide-,sulfide-,and halide-based electrolytes.It then details interfacial optimization strategies focused on addressing three core interfacial issues:ion transport barriers resulting from mechanical incompatibility,side reactions stemming from electrochemical mismatch,and dendrite formation.Finally,the review advocates prioritizing in-depth research that integrates experimental and theoretical approaches to establish a closed-loop methodology encompassing predictive design,multiscale investigation,mechanistic exploration,and high-throughput automated experimentation,with feedback-driven refinement.This work serves as a comprehensive reference and systematic roadmap for future research on solid-state electrolytes(SSEs).
基金the Drug Innovation Major Project(No.2018ZX09711001-001-015)the CAMS Innovation Fund for Medical Sciences(No.2020-I2M-1-003)。
文摘The specific crystalline form of a compound remarkably affects its physicochemical properties.Therefore,a detailed analysis of the structural features and intermolecular interactions of a multi-component crystal is feasible to understand the relationships among the structure,physicochemical properties and the formation mechanism.In the present study,three novel cocrystal salt solvates of rhein and berberine were reported for the first time.Various solid characterizations and theoretical computations based on density functional theory(DFT)were carried out to demonstrate the intermolecular interactions.The theoretical computation shows that the strongest interaction existed between berberine cation and rhein anion,and the electrostatic interaction play a dominant role.However,no salt bond was observed between them.Further intrinsic dissolution rate analysis in water shows that the monohydrate exhibits 17 times enhancement in comparison with rhein.The rhein and berberine combined in ionic state in cocrystal salt is the main reason for the solubility improvement.This paper suggests that the interactions between the different components can be visualized and qualitatively and quantitatively analyzed by theoretical computation,which is helpful to understand the relationship between stereochemical structure and physicochemical properties of multi-component complex.
基金supported by the Industrial Support Plan Project of Gansu Provincial Education Department(2024CYZC-22)。
文摘Electroreduction of nitrite to ammonia(NO_(2)RR)is recognized as an appealing method for achieving renewable NH_(3)production and waste NO_(2)^(-)removal.Herein,monodispersed W-doped ZnO(W_(1-)ZnO)is develo ped as an efficient NO_(2)RR catalyst.Theoretical simulations and in situ spectroscopic measurements unravel that the enhanced NO_(2)RR property of W_(1)-ZnO originates from the creation of active W_(1)-Zn dinuclear sites to selectively activate NO_(2)^(-)and enhance the protonation energetics of NO_(2)^(-)to-NH_(3)pathway,whilst repelling the competing H_(2)evolution.Strikingly,W_(1)-ZnO equipped in flow cell shows an impressive NO_(2)RR performa nce with NH_(3)yield rate of 970μmol h^(-1)cm^(-2)and NH_(3)-Faradaic efficiency of 94.5%.
基金Longyuan Youth Innovative and Entrepreneurial Talents ProjectProgram for Top Leading Talents of Gansu Province。
文摘Electrochemical reduction of NO_(2)-to NH_(3)(NO_(2)-RR) is recognized as an appealing approach for achieving renewable NH_(3)synthesis and waste NO_(2)-removal.Herein,we report isolated Bi alloyed Ru (Bi1Ru) as an efficient NO_(2)-RR catalyst.Theoretical calculations and in situ electrochemical measurements reveal the creation of Bi1-Ru dual sites which can remarkably promote NO_(2)-activation and suppress proton adsorption,while accelerating the NO_(2)-RR protonation energetics to render a high NO_(2)--to-NH_(3)conversion efficiency.Remarkably,Bi1Ru assembled in a flow cell delivers an NH_(3)yield rate of 1901.4μmol h^(-1)cm^(-2)and an NH_(3)-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA cm^(-2).This study offers new perspectives for designing and constructing p-block single-atom alloys as robust and high-current-density NO_(2)-RR catalysts toward the ammonia electrosynthesis.
基金supported by the Provincial Innovation and Entrepreneurship Training Program of Jiangsu Province(No.201910319079Y)。
文摘OX_(2)(X=halogen)molecules was studied theoretically.Calculation results show that delocalizedπ_(3)^(6) bonds exist in their electronic structures and O atoms adopt the sp^(2) type of hybridization,which violates the prediction of the valence shell electron pair repulsion theory of sp^(3) type.Delocalization stabilization energy is proposed to measure the contribution of delocalizedπ_(3)^(6) bond to energy decrease and proves to bring extra-stability to the molecule.These phenomena can be summarized as a kind of coordinating effect.
基金Financial support from the National Natural Science Foundation of China(22075016 and 21805007)Fundamental Research Funds for the Central Universities(FRF-TP-20-020A3)111 Project(B12015 and B170003)is gratefully acknowledged.
文摘NASICON (Na superionic conductor)-type cathode materials for sodium-ion batteries (SIBs) have attractedextensive attention due to their mechanically robust three-dimensional (3D) framework, which has sufficient openchannels for fast Na^(+) transportation. However, they usually suffer from inferior electronic conductivity and lowcapacity, which severely limit their practical applications. To solve these issues, we need to deeply understand thestructural evolution, redox mechanisms, and electrode/electrolyte interface reactions during cycling. Recently,rapid developments in synchrotron X-ray techniques, neutron-based resources, magnetic resonance, as well asoptical and electron microscopy have brought numerous opportunities to gain deep insights into the Na-storagebehaviors of NASICON cathodes. In this review, we summarize the detection principles of advanced characterization techniques used with typical NASICON-structured cathode materials for SIBs. The special focus is on bothoperando and ex situ techniques, which help to investigate the relationships among phase, composition, andvalence variations within electrochemical responses. Fresh electrochemical measurements and theoretical computations are also included to reveal the kinetics and energy-storage mechanisms of electrodes upon charge/discharge. Finally, we describe potential new developments in NASICON-cathodes with optimized SIB systems,foreseeing a bright future for them, achievable through the rational application of advanced diagnostic methods.
文摘Electrochemical converting NO_(2)^(-)into NH_(3)(NO_(2)RR)holds an enormous prospect to attain efficient NH_(3) electrosynthesis and polluted NO_(2)^(-)mitigation.Herein,we report single-atom Co alloyed Ru(Co_(1)Ru)as an efficient and durable NO_(2)RR catalyst.Extensive experimental and theoretical investigations reveal that single-atom Co alloying of Ru enables the construction of Co_(1)-Ru heteronuclear active sites to synergistically promote NO_(2)^(-)activation/hydrogenation while suppressing the competitive H_(2) evolution,rendering the greatly enhanced activity and selectivity of Co_(1)Ru towards the NO_(2)RR.Consequently,Co_(1)Ru assembled within a flow cell exhibits an impressive NH_(3) yield rate of 2379.2μmol·h^(-1)·cm^(-2) with an NH_(3)-Faradaic efficiency of 92%at a high current density of 415.9 mA·cm^(-2),which is among the highest NO_(2)RR performances reported to date.
基金supported by the National Natural Science Foundation of China (52161025)the Natural Science Foundation of Gansu Province (20JR10RA241)。
文摘Electrochemical NO_(2)~--to-NH_(3) conversion(NO_(2)RR) offers a green route to NH_(3) electrosynthesis, while developing efficient NO_(2)RR catalysis systems at high current densities remains a grand challenge. Herein, we report an efficient Zr-NiO catalyst with atomically dispersed Zr-dopants incorporated in NiO lattice, delivering the exceptional NO_(2)RR performance with industriallevel current density(>0.2 A cm^(-2)). In situ spectroscopic measurements and theoretical simulations reveal the construction of ZrNi frustrated Lewis acid-base pairs(FLPs) on Zr-Ni O, which can substantially increase the number of absorbed nitrite(NO_(2)~-),promote the activation and protonation of NO_(2)~- and concurrently hamper the H coverage, boosting the activity and selectivity of Zr-NiO towards the NO_(2)RR. Remarkably, Zr-NiO exhibits the exceptional performance in a flow cell with high Faradaic efficiency for NH_(3) of 94.0% and NH_(3)yield rate of 1,394.1 μmol h^(-1)cm^(-2) at an industrial-level current density of 228.2 m A cm^(-2),placing it among the best NO_(2)RR electrocatalysts for NH_(3) production.
基金financially supported by the Defense Industrial Technology Development Program(JCKY2021-601B019).
文摘Energy materials play an important role in renewable and green energy technologies.The exploration of new materials,including nanomaterials,is important for breaking through the current bottlenecks of energy density and charging rates.However,traditional theoretical computational methods face the dilemma of long research cycles.Machine learning methods have in recent years shown considerable potential for accelerating research efforts.However,most approaches are limited to specific properties of particular devices.In this paper,we propose a forward prediction and screening framework for functional materials,which includes database selection,attributes,descriptors,machine learning models,and prediction and screening.Based on the Materials Project database,auto-encoding methods are employed to generate Coulomb matrices as the input to train the convolutional neural networks,which finally screen 12 lithium-ion,6 zinc-ion,and 8 aluminum-ion battery cathode materials satisfying the criteria from 4,300 materials.The results show that the proposed framework can predict material performance well toward rapid initial screening.The proposed framework can provide a specific and complete working process reference for energy materials design work,contributing to the theoretical foundation for the design of core industrial software for materials engineering.
基金Supported by National High-Tech R&D Programme of China(863)(Grant No.2006AA02Z312)National 111 Programme Introducing Talents of Discipline to Universities(Grant No.0507111106)+6 种基金National Chunhui Project(Grant No.990404+00307)State New Drug Project(Grant No.1996ND1035A01)Fok YingTung Educational Foundation(Grant No.980706)State Key Laboratory of Chemo/Biosensing and Chemometrics Foundation(KCBCF0501201)Chongqing University Innovation Fund(CUIF030506)Chongqing Municipality Applied Science Fund(Grant No.CASF01-3-6)Momentous Juche Innovation Fundfor Tackle Key Problem Items(MJIF 03-5-6+04-10-10)
文摘Only from the primary structures of peptides,a new set of descriptors called the molecular electro-negativity edge-distance vector(VMED)was proposed and applied to describing and characterizing the molecular structures of oligopeptides and polypeptides,based on the electronegativity of each atom or electronic charge index(ECI)of atomic clusters and the bonding distance between atom-pairs.Here,the molecular structures of antigenic polypeptides were well expressed in order to propose the auto-mated technique for the computerized identification of helper T lymphocyte(Th)epitopes.Furthermore,a modified MED vector was proposed from the primary structures of polypeptides,based on the ECI and the relative bonding distance of the fundamental skeleton groups.The side-chains of each amino acid were here treated as a pseudo-atom.The developed VMED was easy to calculate and able to work.Some quantitative model was established for 28 immunogenic or antigenic polypeptides(AGPP)with 14(1―14)Ad and 14 other restricted activities assigned as"1"(+)and"0"(-),respectively.The latter comprised 6 Ab(15-20),3 Ak(21-23),2 Ek(24-26),2 H-2k(27 and 28)restricted sequences.Good results were obtained with 90%correct classification(only 2 wrong ones for 20 training samples)and 100%correct prediction(none wrong for 8 testing samples);while con-trastively 100%correct classification(none wrong for 20 training samples)and 88%correct classification(1 wrong for 8 testing samples).Both stochastic samplings and cross valida-tions were performed to demonstrate good performance.The described method may also be suitable for estimation and prediction of classes I and II for major histocompatibility an-tigen(MHC)epitope of human.It will be useful in immune identification and recognition of pro-teins and genes and in the design and devel-opment of subunit vaccines.Several quantitative structure activity relationship(QSAR)models were developed for various oligopeptides and polypeptides including 58 dipeptides and 31 pentapeptides with angiotensin converting enzyme(ACE)inhibition by multiple linear regression(MLR)method.In order to explain the ability to characterize molecular structure of polypeptides,a molecular modeling investigation on QSAR was performed for functional prediction of polypeptide sequences with anti-genic activity and heptapeptide sequences with tachykinin activity through quantitative se-quence-activity models(QSAMs)by the molecular electronegativity edge-distance vector(VMED).The results showed that VMED exhibited both excellent structural selectivity and good activity prediction.Moreover,the results showed that VMED behaved quite well for both QSAR and QSAM of poly-and oli-gopeptides,which exhibited both good estimation ability and prediction power,equal to or better than those reported in the previous references.Finally,a preliminary conclusion was drwan:both classical and modified MED vectors were very useful structural descriptors.Some suggestions were proposed for further studies on QSAR/QSAM of proteins in various fields.