304H austenitic stainless steel wire was investigated,emphasizing microstructural deformation,martensite phase transformation,and residual magnetic properties during drawing.Utilizing several microstructural observati...304H austenitic stainless steel wire was investigated,emphasizing microstructural deformation,martensite phase transformation,and residual magnetic properties during drawing.Utilizing several microstructural observation techniques,the volume fraction of martensite,modes of grain deformation in distinct regions,and the phase relationship between austenite and martensite were comprehensively characterized.In addition,a finite element simulation with representative volume elements specific to different zones also offers insights into strain responses during the drawing process.Results from the first-pass drawing reveal that there exists a higher volume fraction of martensite in the central region of 304H austenitic stainless steel wire compared to edge areas.This discrepancy is attributed to a concentrated presence of shear slip system{111}<110>γcrystallographic orientation,primarily accumulating in the central region obeying the Kurdjumov-Sachs path.Subsequent to the second drawing pass,the cumulative shear deformation within distinct regions of the steel wire became more pronounced.This resulted in a progressive augmentation of the volume fraction of martensite in both the central and peripheral regions of the steel wire.Concurrently,this led to a discernible elevation in the overall residual magnetism of the steel wire.展开更多
Performance of the oxidative coupling of methane in fluidized-bed reactor was experimentally investigated using Mn-Na2WO4/SiO2,La2O3/CaO and La2O3-SrO/CaO catalysts.These catalysts were found to be stable,especially M...Performance of the oxidative coupling of methane in fluidized-bed reactor was experimentally investigated using Mn-Na2WO4/SiO2,La2O3/CaO and La2O3-SrO/CaO catalysts.These catalysts were found to be stable,especially Mn-Na2WO4/SiO2 catalyst.The effect of sodium content of this catalyst was analyzed and the challenge of catalyst agglomeration was addressed using proper catalyst composition of 2%Mn2.2%Na2WO4/SiO2.For other two catalysts,the effect of Lanthanum-Strontium content was analyzed and 10%La2O 3-20%SrO/CaO catalyst was found to provide higher ethylene yield than La2O3/CaO catalyst.Furthermore,the effect of operating parameters such as temperature and methane to oxygen ratio were also reviewed.The highest ethylene and ethane （C2） yield was achieved with the lowest methane to oxygen ratio around 2.40.5% selectivity to ethylene and ethane and 41% methane conversion were achieved over La2O3-SrO/CaO catalyst while over Mn-Na2WO4 /SiO2 catalyst,40% and 48% were recorded,respectively.Moreover,the consecutive effects of nitrogen dilution,ethylene to ethane production ratio and other performance indicators on the down-stream process units were qualitatively discussed and Mn-Na2WO4/SiO2 catalyst showed a better performance in the reactor and process scale analysis.展开更多
Co68.15Fe4.35Si12.25B15.25 （at%） amorphous microwires with a smooth surface and a circular cross-section were fabricated by the glass-coated melt spinning method. Their mechanical properties were evaluated through t...Co68.15Fe4.35Si12.25B15.25 （at%） amorphous microwires with a smooth surface and a circular cross-section were fabricated by the glass-coated melt spinning method. Their mechanical properties were evaluated through tensile tests of the glass-coated amorphous mi-crowires, and their fracture reliability was estimated using two-and three-parameter Weibull analysis. X-ray diffraction and transmission electron microscopy results showed that these glass-coated Co-based microwires were mostly amorphous. The coated Co-based microwires exhibit a tensile strength of 1145 to 2457 MPa, with a mean value of 1727 MPa and a variance of 445 MPa. Weibull statistical analysis showed that the tensile two-parameter Weibull modulus of the amorphous microwires is 4.16 and the three-parameter Weibull modulus is 1.61 with a threshold value as high as 942 MPa. These results indicate that the fabricated microwires exhibit good tensile properties and fracture reliability, and thus appear to be good candidates for electronics reliability engineering applications.展开更多
The Paulie’s principle is used for development of the orbital-free (OF) version of the density functional theory. On the example of the three-atomic clusters, Al<sub>3</sub>, Si<sub>3</sub>, a...The Paulie’s principle is used for development of the orbital-free (OF) version of the density functional theory. On the example of the three-atomic clusters, Al<sub>3</sub>, Si<sub>3</sub>, and C<sub>3</sub>, it is shown that the OF approach may lead to equilibrium configurations of atomic systems with both the metallic and covalent bonding. The equilibrium interatomic distances, interbonding angles and binding energies are found in good accordance with the known data. Results will be useful for developing of theoretical study of huge molecules and nanoparticles.展开更多
Condensed matters with high ionic conductivities are crucial in various solid devices such as solid-state batteries. The conduction ischaracterized by the cooperative ionic motion associated with the high carrier dens...Condensed matters with high ionic conductivities are crucial in various solid devices such as solid-state batteries. The conduction ischaracterized by the cooperative ionic motion associated with the high carrier density. However, the high cost of computingcorrelated ionic conductivities has forced almost all ab initio molecular dynamics (MD) to rely on the Nernst–Einstein dilute-solutionapproximation, which ignores the cross-correlation effect. Here we develop a chemical color-diffusion nonequilibrium MD (CCD-NEMD) method, which enables to calculate the correlated conductivities with fewer sampling steps than the conventional MD. ThisCCD-NEMD is demonstrated to well evaluate the conductivities in the representative solid electrolyte bulk Li10GeP2S12 andLi_(7)La_(3)Zr_(2)O_(12). We also applied CCD-NEMD to the grain boundary of Li_(7)La_(3)Zr_(2)O_(12) and demonstrated its applicability for calculatinginterfacial local conductivities, which is essential for investigating grain boundaries and composite electrolytes. CCD-NEMD canprovide further accurate understanding of ionics with ionic correlations and promote developing solid devices.展开更多
Aqueous zinc-ion batteries(AZIBs)have attracted widespread attention due to their intrinsic merits of low cost and high safety.However,the poor thermodynamic stability of Zn metal in aqueous electrolytes inevitably ca...Aqueous zinc-ion batteries(AZIBs)have attracted widespread attention due to their intrinsic merits of low cost and high safety.However,the poor thermodynamic stability of Zn metal in aqueous electrolytes inevitably cause Zn dendrites growth and interface parasitic side reactions,resulting in unsatisfactory cycling stability and low Zn utilization.Replacing Zn anode with intercalation-type anodes have emerged as a promising alternative strategy to overcome the above issues but the lack of appropriate anode materials is becoming the bottleneck.Herein,the interlayer structure of MoSe_(2) anode is preintercalated with long-chain polyvinyl pyrrolidone(PVP),constructing a periodically stacked p-MoSe_(2)superlattice to activate the reversible Zn^(2+) storage performance(203 mAh g^(−1)at 0.2 A g^(−1)).To further improve the stability of the superlattice structure during cycling,the electrolyte is also rationally designed by adding 1,4-Butyrolactone(γ-GBL)additive into 3 M Zn(CF_(3)SO_(3))_(2),in whichγ-GBL replaces the H2O in Zn^(2+) solvation sheath.The preferential solvation ofγ-GBL with Zn^(2+)effectively reduces the water activity and helps to achieve an ultra-long lifespan of 12,000 cycles for p-MoSe_(2).More importantly,the reconstructed solvation structure enables the operation of p-MoSe_(2)||ZnxNVPF(Na3V2(PO4)2O_(2)F)AZIBs at an ultra-low temperature of−40°C,which is expected to promote the practical applications of AZIBs.展开更多
In contrast to the static operations of conventional semiconductor devices,the dynamic conformational freedom in molecular devices opens up the possibility of using individual molecules as new types of devices such as...In contrast to the static operations of conventional semiconductor devices,the dynamic conformational freedom in molecular devices opens up the possibility of using individual molecules as new types of devices such as a molecular conformational switch or for molecular data storage.Bistable molecules such as those having two stable cis and trans isomeric confi gurations could provide,once clamped between two electrodes,a switching phenomenon in the non-equilibrium current response.Here,we model molecular switch junctions formed at silicon contacts and demonstrate the potential of such tunable molecular switches in electrode/molecule/electrode confi gurations.Using the non-equilibrium Green function(NEGF)approach implemented with the density-functional-based tight-binding(DFTB)theory,a series of properties such as electron transmissions,current voltage characteristics in the different isomer conformations,and potential energy surfaces(PESs)as a function of the reaction coordinates along the trans to cis transition were calculated for two azobenzene-based model compounds.Furthermore,in order to investigate the stability of molecular switches under ambient conditions,molecular dynamics(MD)simulations at room temperature were performed and time-dependent fl uctuations of the conductance along the MD pathways were calculated.Our numerical results show that the transmission spectra of the cis isomers are more conductive than trans counterparts inside the bias window for both model compounds.The currentvoltage characteristics consequently show the same trends.Additionally,calculations of the time-dependent transmission fluctuations along the MD pathways have shown that the transmission in the cis isomers is always signifi cantly larger than that in their trans counterparts,showing that molecular switches can be expected to work as robust molecular switching components.展开更多
Random lasing is observed in optically active resonators in the presence of disorder.As the optical cavities involved are open,the modes are coupled,and energy may pour from one state to another provided that they are...Random lasing is observed in optically active resonators in the presence of disorder.As the optical cavities involved are open,the modes are coupled,and energy may pour from one state to another provided that they are spatially overlapping.Although the electromagnetic modes are spatially localized,our system may be actively switched to a collective state,presenting a novel form of non-locality revealed by a high degree of spectral correlation between the light emissions collected at distant positions.In a nutshell,light may be stored in a disordered nonlinear structure in different fashions that strongly differ in their spatial properties.This effect is experimentally demonstrated and theoretically explained in titania clusters embedded in a dye,and it provides clear evidence of a transition to a multimodal collective emission involving the entire spatial extent of the disordered system.Our results can be used to develop a novel type of miniaturized,actively controlled all-optical chip.展开更多
基金funded by National Natural Science Foundation of China(52201084 and 52231003)Major Program(JD)of Hubei Province(2023BAA019)+2 种基金China Scholarship Council(CSC)Postdoctoral Station of metallurgical Engineering of Wuhan University of Science and Technology(WUST)Postdoctoral workstation of Zhejiang Jincheng New Material Co.,Ltd.
文摘304H austenitic stainless steel wire was investigated,emphasizing microstructural deformation,martensite phase transformation,and residual magnetic properties during drawing.Utilizing several microstructural observation techniques,the volume fraction of martensite,modes of grain deformation in distinct regions,and the phase relationship between austenite and martensite were comprehensively characterized.In addition,a finite element simulation with representative volume elements specific to different zones also offers insights into strain responses during the drawing process.Results from the first-pass drawing reveal that there exists a higher volume fraction of martensite in the central region of 304H austenitic stainless steel wire compared to edge areas.This discrepancy is attributed to a concentrated presence of shear slip system{111}<110>γcrystallographic orientation,primarily accumulating in the central region obeying the Kurdjumov-Sachs path.Subsequent to the second drawing pass,the cumulative shear deformation within distinct regions of the steel wire became more pronounced.This resulted in a progressive augmentation of the volume fraction of martensite in both the central and peripheral regions of the steel wire.Concurrently,this led to a discernible elevation in the overall residual magnetism of the steel wire.
基金supported by the Deutsche Forschungsgemeinschaft (DFG)
文摘Performance of the oxidative coupling of methane in fluidized-bed reactor was experimentally investigated using Mn-Na2WO4/SiO2,La2O3/CaO and La2O3-SrO/CaO catalysts.These catalysts were found to be stable,especially Mn-Na2WO4/SiO2 catalyst.The effect of sodium content of this catalyst was analyzed and the challenge of catalyst agglomeration was addressed using proper catalyst composition of 2%Mn2.2%Na2WO4/SiO2.For other two catalysts,the effect of Lanthanum-Strontium content was analyzed and 10%La2O 3-20%SrO/CaO catalyst was found to provide higher ethylene yield than La2O3/CaO catalyst.Furthermore,the effect of operating parameters such as temperature and methane to oxygen ratio were also reviewed.The highest ethylene and ethane （C2） yield was achieved with the lowest methane to oxygen ratio around 2.40.5% selectivity to ethylene and ethane and 41% methane conversion were achieved over La2O3-SrO/CaO catalyst while over Mn-Na2WO4 /SiO2 catalyst,40% and 48% were recorded,respectively.Moreover,the consecutive effects of nitrogen dilution,ethylene to ethane production ratio and other performance indicators on the down-stream process units were qualitatively discussed and Mn-Na2WO4/SiO2 catalyst showed a better performance in the reactor and process scale analysis.
基金financially supported by the National Natural Science Foundation of China(No.51371067)supported by the Japan Society for the Promotion of Science(JSPS) fellowship and Grants-in-Aid for Scientific Research(No.25-03205)
文摘Co68.15Fe4.35Si12.25B15.25 （at%） amorphous microwires with a smooth surface and a circular cross-section were fabricated by the glass-coated melt spinning method. Their mechanical properties were evaluated through tensile tests of the glass-coated amorphous mi-crowires, and their fracture reliability was estimated using two-and three-parameter Weibull analysis. X-ray diffraction and transmission electron microscopy results showed that these glass-coated Co-based microwires were mostly amorphous. The coated Co-based microwires exhibit a tensile strength of 1145 to 2457 MPa, with a mean value of 1727 MPa and a variance of 445 MPa. Weibull statistical analysis showed that the tensile two-parameter Weibull modulus of the amorphous microwires is 4.16 and the three-parameter Weibull modulus is 1.61 with a threshold value as high as 942 MPa. These results indicate that the fabricated microwires exhibit good tensile properties and fracture reliability, and thus appear to be good candidates for electronics reliability engineering applications.
文摘The Paulie’s principle is used for development of the orbital-free (OF) version of the density functional theory. On the example of the three-atomic clusters, Al<sub>3</sub>, Si<sub>3</sub>, and C<sub>3</sub>, it is shown that the OF approach may lead to equilibrium configurations of atomic systems with both the metallic and covalent bonding. The equilibrium interatomic distances, interbonding angles and binding energies are found in good accordance with the known data. Results will be useful for developing of theoretical study of huge molecules and nanoparticles.
基金This work was supported by JSPS KAKENHI(JP19H05815 and JP21J12566),JST-CREST(Grant No.JPMJCR2204)MEXT as part of the“Program for Promoting Research on the Supercomputer Fugaku(Fugaku Battery&Fuel Cell Project),grant number JPMXP1020200301”+1 种基金The calculations were carried out on the supercomputers at the National Institute for Materials Science(NIMS),the TSUBAME 3.0 at the Tokyo Institute of Technology(MEXT Project of the TAC-MI)the supercomputer Fugaku at the RIKEN through the HPCI Systems(HPCI System Research Projects(hp200131 and hp210173)).
文摘Condensed matters with high ionic conductivities are crucial in various solid devices such as solid-state batteries. The conduction ischaracterized by the cooperative ionic motion associated with the high carrier density. However, the high cost of computingcorrelated ionic conductivities has forced almost all ab initio molecular dynamics (MD) to rely on the Nernst–Einstein dilute-solutionapproximation, which ignores the cross-correlation effect. Here we develop a chemical color-diffusion nonequilibrium MD (CCD-NEMD) method, which enables to calculate the correlated conductivities with fewer sampling steps than the conventional MD. ThisCCD-NEMD is demonstrated to well evaluate the conductivities in the representative solid electrolyte bulk Li10GeP2S12 andLi_(7)La_(3)Zr_(2)O_(12). We also applied CCD-NEMD to the grain boundary of Li_(7)La_(3)Zr_(2)O_(12) and demonstrated its applicability for calculatinginterfacial local conductivities, which is essential for investigating grain boundaries and composite electrolytes. CCD-NEMD canprovide further accurate understanding of ionics with ionic correlations and promote developing solid devices.
基金National Natural Science Foundation of China,Grant/Award Numbers:22109030,22021001Fundamental Research Funds for the Central Universities,Grant/Award Number:20720220073+1 种基金The Key Research and Development Program of Yunnan Province,Grant/Award Number:202103AA080019Fujian Industrial Technology Development,and Application Plan,Grant/Award Number:2022I0002。
文摘Aqueous zinc-ion batteries(AZIBs)have attracted widespread attention due to their intrinsic merits of low cost and high safety.However,the poor thermodynamic stability of Zn metal in aqueous electrolytes inevitably cause Zn dendrites growth and interface parasitic side reactions,resulting in unsatisfactory cycling stability and low Zn utilization.Replacing Zn anode with intercalation-type anodes have emerged as a promising alternative strategy to overcome the above issues but the lack of appropriate anode materials is becoming the bottleneck.Herein,the interlayer structure of MoSe_(2) anode is preintercalated with long-chain polyvinyl pyrrolidone(PVP),constructing a periodically stacked p-MoSe_(2)superlattice to activate the reversible Zn^(2+) storage performance(203 mAh g^(−1)at 0.2 A g^(−1)).To further improve the stability of the superlattice structure during cycling,the electrolyte is also rationally designed by adding 1,4-Butyrolactone(γ-GBL)additive into 3 M Zn(CF_(3)SO_(3))_(2),in whichγ-GBL replaces the H2O in Zn^(2+) solvation sheath.The preferential solvation ofγ-GBL with Zn^(2+)effectively reduces the water activity and helps to achieve an ultra-long lifespan of 12,000 cycles for p-MoSe_(2).More importantly,the reconstructed solvation structure enables the operation of p-MoSe_(2)||ZnxNVPF(Na3V2(PO4)2O_(2)F)AZIBs at an ultra-low temperature of−40°C,which is expected to promote the practical applications of AZIBs.
基金by the Volkswagen Foundation by the Deutsche Forshuhgsgemeinschaft(DFG)under Contracts No.CU 44/5-2,CU 44/8-1,and CU 44/3-3by the WCU(World Class University)program through the Korea Science and Engineering Foundation funded by the Ministry of Education,Science and Technology(Project No.R31-2008-000-10100-0).
文摘In contrast to the static operations of conventional semiconductor devices,the dynamic conformational freedom in molecular devices opens up the possibility of using individual molecules as new types of devices such as a molecular conformational switch or for molecular data storage.Bistable molecules such as those having two stable cis and trans isomeric confi gurations could provide,once clamped between two electrodes,a switching phenomenon in the non-equilibrium current response.Here,we model molecular switch junctions formed at silicon contacts and demonstrate the potential of such tunable molecular switches in electrode/molecule/electrode confi gurations.Using the non-equilibrium Green function(NEGF)approach implemented with the density-functional-based tight-binding(DFTB)theory,a series of properties such as electron transmissions,current voltage characteristics in the different isomer conformations,and potential energy surfaces(PESs)as a function of the reaction coordinates along the trans to cis transition were calculated for two azobenzene-based model compounds.Furthermore,in order to investigate the stability of molecular switches under ambient conditions,molecular dynamics(MD)simulations at room temperature were performed and time-dependent fl uctuations of the conductance along the MD pathways were calculated.Our numerical results show that the transmission spectra of the cis isomers are more conductive than trans counterparts inside the bias window for both model compounds.The currentvoltage characteristics consequently show the same trends.Additionally,calculations of the time-dependent transmission fluctuations along the MD pathways have shown that the transmission in the cis isomers is always signifi cantly larger than that in their trans counterparts,showing that molecular switches can be expected to work as robust molecular switching components.
基金The research leading to these results has received funding from the ERC under the EC’s Seventh Framework Program(FP7/2007-2013)grant agreement n.201766,EU FP7 NoE Nanophotonics4Enery Grant No.248855the Spanish MICINN CSD2007-0046(Nanolight.es)+1 种基金MAT2009-07841(GLUSFA)and Comunidad de Madrid S2009/MAT2012-31659.
文摘Random lasing is observed in optically active resonators in the presence of disorder.As the optical cavities involved are open,the modes are coupled,and energy may pour from one state to another provided that they are spatially overlapping.Although the electromagnetic modes are spatially localized,our system may be actively switched to a collective state,presenting a novel form of non-locality revealed by a high degree of spectral correlation between the light emissions collected at distant positions.In a nutshell,light may be stored in a disordered nonlinear structure in different fashions that strongly differ in their spatial properties.This effect is experimentally demonstrated and theoretically explained in titania clusters embedded in a dye,and it provides clear evidence of a transition to a multimodal collective emission involving the entire spatial extent of the disordered system.Our results can be used to develop a novel type of miniaturized,actively controlled all-optical chip.
