A novel technique of Moveable Reduction Bed Hydride Generator(MRBHG)was applied tohe hydride generation or cold vapor generation of As,Se,Ge,and Hg existing In TraditionalChinese Medicinal Material(TCM).The si...A novel technique of Moveable Reduction Bed Hydride Generator(MRBHG)was applied tohe hydride generation or cold vapor generation of As,Se,Ge,and Hg existing In TraditionalChinese Medicinal Material(TCM).The simultaneous determination of the multi-elements wasperformed with ICP-MS.A solid reduction system involving the use of potassiumtetraborohydride and tartaric acid was applied to generating metal hydride or cold vaporefficiently.The factors affecting the metal cold vapor generation were studied.The mainadvantage of the technique is that only a 4μL volume of sample was required for the cold vapor展开更多
Dynamic modeling for incompressible hyperelastic materials with large deformation is an important issue in biomimetic applications. The previously proposed lower-order fully parameterized absolute nodal coordinate for...Dynamic modeling for incompressible hyperelastic materials with large deformation is an important issue in biomimetic applications. The previously proposed lower-order fully parameterized absolute nodal coordinate formulation(ANCF) beam element employs cubic interpolation in the longitudinal direction and linear interpolation in the transverse direction, whereas it cannot accurately describe the large bending deformation. On this account, a novel modeling method for studying the dynamic behavior of nonlinear materials is proposed in this paper. In this formulation, a higher-order beam element characterized by quadratic interpolation in the transverse directions is used in this investigation. Based on the Yeoh model and volumetric energy penalty function, the nonlinear elastic force matrices are derived within the ANCF framework. The feasibility and availability of the Yeoh model are verified through static experiment of nonlinear incompressible materials. Furthermore,dynamic simulation of a silicone cantilever beam under the gravity force is implemented to validate the superiority of the higher-order beam element. The simulation results obtained based on the Yeoh model by employing three different ANCF beam elements are compared with the result achieved from a commercial finite element package as the reference result. It is found that the results acquired utilizing a higher-order beam element are in good agreement with the reference results,while the results obtained using a lower-order beam element are different from the reference results. In addition, the stiffening problem caused by volumetric locking can be resolved effectively by applying a higher-order beam element. It is concluded that the proposed higher-order beam element formulation has satisfying accuracy in simulating dynamic motion process of the silicone beam.展开更多
In this work, a novel carbon allotrope tP40 carbon with space group P4/mmm is proposed. The structural stability, mechanical properties, elastic anisotropy, and electronic properties of tP40 carbon are investigated sy...In this work, a novel carbon allotrope tP40 carbon with space group P4/mmm is proposed. The structural stability, mechanical properties, elastic anisotropy, and electronic properties of tP40 carbon are investigated systematically by using density functional theory (DFT). The calculated elastic constants and phonon dispersion spectra indicate that the tP40 phase is a metastable carbon phase with mechanical stability and dynamic stability. The B/G ratio indicates that tP40 carbon is brittle from 0 GPa to 60 GPa, while tP40 carbon is ductile from 70 GPa to 100 GPa. Additionally, the anisotropic factors and the directional dependence of the Poisson's ratio, shear modulus, and Young's modulus of tP40 carbon at different pressures are estimated and plotted, suggesting that the tP40 carbon is elastically anisotropic. The calculated hardness values of tP40 carbon are 44.0 GPa and 40.2 GPa obtained by using Lyakhov–Oganov's model and Chen's model, respectively, which means that the tP40 carbon can be considered as a superhard material. The electronic band gap within Heyd–Scuseria–Ernzerhof hybrid functional (HSE06) is 4.130 eV, and it is found that the tP40 carbon is an indirect and wider band gap semiconductor material.展开更多
Generative Artificial Intelligence(GAI)is attracting the increasing attention of materials community for its excellent capability of generating required contents.With the introduction of Prompt paradigm and reinforcem...Generative Artificial Intelligence(GAI)is attracting the increasing attention of materials community for its excellent capability of generating required contents.With the introduction of Prompt paradigm and reinforcement learning from human feedback(RLHF),GAI shifts from the task-specific to general pattern gradually,enabling to tackle multiple complicated tasks involved in resolving the structure-activity relationships.Here,we review the development status of GAI comprehensively and analyze pros and cons of various generative models in the view of methodology.The applications of task-specific generative models involving materials inverse design and data augmentation are also dissected.Taking ChatGPT as an example,we explore the potential applications of general GAI in generating multiple materials content,solving differential equation as well as querying materials FAQs.Furthermore,we summarize six challenges encountered for the use of GAI in materials science and provide the corresponding solutions.This work paves the way for providing effective and explainable materials data generation and analysis approaches to accelerate the materials research and development.展开更多
The ion substitution characteristics of Y3+-doped (Tb0.sY0.2)3A15012 transparent ceramics synthesized by a solid-state reaction and vacuum sintering are investigated. The sample sintered at 1 680℃ exhibits the bes...The ion substitution characteristics of Y3+-doped (Tb0.sY0.2)3A15012 transparent ceramics synthesized by a solid-state reaction and vacuum sintering are investigated. The sample sintered at 1 680℃ exhibits the best optical properties, yielding a transmittance 〉75% from 900 to 1 600 nm. The Verdet constant of this sample at 632.8 nm is -108.79 rad.T-l.m-1. X-ray diffraction (XRD) results show that all of the samples have a pure garnet crystal structure without secondary phases. The microstructure of the samples reveals homogeneous grain sizes that averages 〈10μm.展开更多
A novel hard material with various (W0.5Al0.5)C grain shapes was successfully prepared through mechanical alloying and in-situ high-pressure sintering process. X-ray diffraction apparatus and scanning electron micro...A novel hard material with various (W0.5Al0.5)C grain shapes was successfully prepared through mechanical alloying and in-situ high-pressure sintering process. X-ray diffraction apparatus and scanning electron microscopy were used to characterize the phase and the microstructures of the samples. The novel hard materials with "fibrous", "rounded" and "plate-like" grains, which do not contain sharp edges, have the improved mechanical properties. The bulk boundless (W0.5Al0.5)C hard material with various (W0.5Al0.5)C grain shapes possesses good mechanical properties and light weight. The formation mechanism for the non-equilibrium (W0.5Al0.5)C grains during in-situ high-pressure sintering is also discussed.展开更多
文摘A novel technique of Moveable Reduction Bed Hydride Generator(MRBHG)was applied tohe hydride generation or cold vapor generation of As,Se,Ge,and Hg existing In TraditionalChinese Medicinal Material(TCM).The simultaneous determination of the multi-elements wasperformed with ICP-MS.A solid reduction system involving the use of potassiumtetraborohydride and tartaric acid was applied to generating metal hydride or cold vaporefficiently.The factors affecting the metal cold vapor generation were studied.The mainadvantage of the technique is that only a 4μL volume of sample was required for the cold vapor
基金supported by the National Natural Science Foundation of China (11772186 and 11272203)
文摘Dynamic modeling for incompressible hyperelastic materials with large deformation is an important issue in biomimetic applications. The previously proposed lower-order fully parameterized absolute nodal coordinate formulation(ANCF) beam element employs cubic interpolation in the longitudinal direction and linear interpolation in the transverse direction, whereas it cannot accurately describe the large bending deformation. On this account, a novel modeling method for studying the dynamic behavior of nonlinear materials is proposed in this paper. In this formulation, a higher-order beam element characterized by quadratic interpolation in the transverse directions is used in this investigation. Based on the Yeoh model and volumetric energy penalty function, the nonlinear elastic force matrices are derived within the ANCF framework. The feasibility and availability of the Yeoh model are verified through static experiment of nonlinear incompressible materials. Furthermore,dynamic simulation of a silicone cantilever beam under the gravity force is implemented to validate the superiority of the higher-order beam element. The simulation results obtained based on the Yeoh model by employing three different ANCF beam elements are compared with the result achieved from a commercial finite element package as the reference result. It is found that the results acquired utilizing a higher-order beam element are in good agreement with the reference results,while the results obtained using a lower-order beam element are different from the reference results. In addition, the stiffening problem caused by volumetric locking can be resolved effectively by applying a higher-order beam element. It is concluded that the proposed higher-order beam element formulation has satisfying accuracy in simulating dynamic motion process of the silicone beam.
基金Project supported by the National Natural Science Foundationof China(Grant Nos.61804120 and 61901162)the China Postdoctoral Science Foundation(Grant Nos.2019TQ0243 and 2019M663646)+2 种基金the Young Talent Fund of University Association for Science and Technology in Shaanxi Province,China(Grant No.20190110)the National Key Research and Development Program of China(Grant No.2018YFB1502902)the Key Program for International Science and Technolog Cooperation Projects of Shaanxi Province,China(Grant No.2019KWZ-03).
文摘In this work, a novel carbon allotrope tP40 carbon with space group P4/mmm is proposed. The structural stability, mechanical properties, elastic anisotropy, and electronic properties of tP40 carbon are investigated systematically by using density functional theory (DFT). The calculated elastic constants and phonon dispersion spectra indicate that the tP40 phase is a metastable carbon phase with mechanical stability and dynamic stability. The B/G ratio indicates that tP40 carbon is brittle from 0 GPa to 60 GPa, while tP40 carbon is ductile from 70 GPa to 100 GPa. Additionally, the anisotropic factors and the directional dependence of the Poisson's ratio, shear modulus, and Young's modulus of tP40 carbon at different pressures are estimated and plotted, suggesting that the tP40 carbon is elastically anisotropic. The calculated hardness values of tP40 carbon are 44.0 GPa and 40.2 GPa obtained by using Lyakhov–Oganov's model and Chen's model, respectively, which means that the tP40 carbon can be considered as a superhard material. The electronic band gap within Heyd–Scuseria–Ernzerhof hybrid functional (HSE06) is 4.130 eV, and it is found that the tP40 carbon is an indirect and wider band gap semiconductor material.
基金National Natural Science Foundation of China[grant number 92270124,52073169]National Key Research and Development Program of China[grant number 2021YFB3802101]the Key Research Project of Zhejiang Laboratory[grant number 2021PE0AC02].
文摘Generative Artificial Intelligence(GAI)is attracting the increasing attention of materials community for its excellent capability of generating required contents.With the introduction of Prompt paradigm and reinforcement learning from human feedback(RLHF),GAI shifts from the task-specific to general pattern gradually,enabling to tackle multiple complicated tasks involved in resolving the structure-activity relationships.Here,we review the development status of GAI comprehensively and analyze pros and cons of various generative models in the view of methodology.The applications of task-specific generative models involving materials inverse design and data augmentation are also dissected.Taking ChatGPT as an example,we explore the potential applications of general GAI in generating multiple materials content,solving differential equation as well as querying materials FAQs.Furthermore,we summarize six challenges encountered for the use of GAI in materials science and provide the corresponding solutions.This work paves the way for providing effective and explainable materials data generation and analysis approaches to accelerate the materials research and development.
基金supported by the National Natural Science Foundation of China(Nos.51172254 and 51202269)the Science and Technology Commission of Shanghai Municipality(No.10JC1415700)
文摘The ion substitution characteristics of Y3+-doped (Tb0.sY0.2)3A15012 transparent ceramics synthesized by a solid-state reaction and vacuum sintering are investigated. The sample sintered at 1 680℃ exhibits the best optical properties, yielding a transmittance 〉75% from 900 to 1 600 nm. The Verdet constant of this sample at 632.8 nm is -108.79 rad.T-l.m-1. X-ray diffraction (XRD) results show that all of the samples have a pure garnet crystal structure without secondary phases. The microstructure of the samples reveals homogeneous grain sizes that averages 〈10μm.
基金supported by the National Natural Science Foundation of China(No.50371080)the Project of Science and Technology Development Program(No.20030508) of Jilin Province, Chinathe financial support from the Alexander von Humboldt Foundation
文摘A novel hard material with various (W0.5Al0.5)C grain shapes was successfully prepared through mechanical alloying and in-situ high-pressure sintering process. X-ray diffraction apparatus and scanning electron microscopy were used to characterize the phase and the microstructures of the samples. The novel hard materials with "fibrous", "rounded" and "plate-like" grains, which do not contain sharp edges, have the improved mechanical properties. The bulk boundless (W0.5Al0.5)C hard material with various (W0.5Al0.5)C grain shapes possesses good mechanical properties and light weight. The formation mechanism for the non-equilibrium (W0.5Al0.5)C grains during in-situ high-pressure sintering is also discussed.