The sol-gel process, sing aqueous solutions, is used for dip coating ontosubstrates of 316L stainless steel. A suitable coating of Li CoO_2 is achieved by varying thethickness and heat treating at 650 deg C for 3 h. T...The sol-gel process, sing aqueous solutions, is used for dip coating ontosubstrates of 316L stainless steel. A suitable coating of Li CoO_2 is achieved by varying thethickness and heat treating at 650 deg C for 3 h. Thermal analysis, X-ray diffraction analysis andSEM are carried out to characterize the microstructure of the coatings. The results show that thecoating transforms from an amorphous gel to crystalline phases above 350 deg C, and show a porousstructure. The phase transition mechanism is discussed.展开更多
We consider a bistable mesoscopic chemical reaction system and calculate entropy produc- tion along the dominant pathway during nonequilibrium phase transition. Using probability generating function method and eikonal...We consider a bistable mesoscopic chemical reaction system and calculate entropy produc- tion along the dominant pathway during nonequilibrium phase transition. Using probability generating function method and eikonal approximation, we first convert the chemical master equation into the classical Hamilton-Jacobi equation, and then find the dominant pathways between two steady states in the phase space by calculating zero-energy trajectories. We find that entropy productions are related to the actions of the forward and backward dominant pathways. At the coexistence point where the stabilities of the two steady states are equiv alent, both the system entropy change and the medium entropy change are zero; whereas at non-coexistence point both of them are nonzero.展开更多
The heat and mass transfer characteristics under frosting on surface of heat exchanger were experimentally investigated in different conditions of air temperature, relative humidity, and face velocity. The heat transf...The heat and mass transfer characteristics under frosting on surface of heat exchanger were experimentally investigated in different conditions of air temperature, relative humidity, and face velocity. The heat transfer and heat transfer coefficient decreased faster with the high relative humidity, low air temperature and initial face velocity. The air pressure drop rose faster with the high relative humidity and low air velocity.展开更多
Molecular-based ferroelastics with dielectric switching properties are highly desirable for their applications on microelectronic dielectric switches,sensors,data storage,and so on.However,the current reports mostly f...Molecular-based ferroelastics with dielectric switching properties are highly desirable for their applications on microelectronic dielectric switches,sensors,data storage,and so on.However,the current reports mostly focus on organic-inorganic hybrids containing toxic heavy metal atoms,and the relatively low phase transition temperature limits their application.In this paper,low-toxic organic salt ferroelastic enantiomers(R/S)-4-fluoro-1-azabicyclo[3.2.1]octonium chloride[(R/S)-F-321]were designed and synthesized under the introducing chirality strategy.They undergo a 432F422-type ferroelastic phase transition with a high Curie temperature(Tc)of 470 K,simultaneously exhibiting excellent dielectric switching characteristics.In addition to the ordered-disordered movement of cations,the significant displacement of anions is also responsible for such high Tc and large dielectric switching ratios,which is very rare in molecular-based switching materials.This work enriches the development of molecular ferroelastic switching materials and gives inspiration for the exploration of environmentally friendly high Tc organic salt ferroelastics with prominent switching performances.展开更多
The existence of adsorbed water and structural water in the crystal structure of attapulgite(ATP)endows it with poor capability to store lithium ions.Herein,the chloride molten salt method was developed to function AT...The existence of adsorbed water and structural water in the crystal structure of attapulgite(ATP)endows it with poor capability to store lithium ions.Herein,the chloride molten salt method was developed to function ATP materials based on theoretical calculations,which exhibit ground-breaking electrochemical performance.After the modification process,the metal ions in chloride molten salt occupy the vertices of the Mg-O octahedral structure from the liberation of structural water and hydroxyl groups in ATP,forming MaMgbAlcSixOy(M=Li,Na,or K).Using Li Cl molten salt-modified ATP(Li-ATP)as a proof-of-concept,the detailed phase transition,physicochemical properties,and lithium storage capacity were investigated.Compared to the original ATP,Li-ATP achieves a nearly 7-fold increase in lithium storage capacity(498mAh/g),featuring a promising low-cost polyanionic type anode material.展开更多
Strain engineering provides an effective mean of tuning the fundamental properties of semiconductors for electric and optoelectronic applications. Here we report on how the applied strain changes the emission properti...Strain engineering provides an effective mean of tuning the fundamental properties of semiconductors for electric and optoelectronic applications. Here we report on how the applied strain changes the emission properties of hetero- structures consisting of different crystalline phases in the same CdS nanobelts. The strained portion was found to produce an additional emission peak on the low-energy side that was blueshifted with increasing strain. Furthermore, the additional emission peak obeyed the Varshni equation with temperature and exhibited the band-filling effect at high excitation power. This new emission peak may be attributed to spatially indirect exciton recombination between different crystalline phases of CdS. First-principles calculations were performed based on the spatially indirect exciton recombination, and the calculated and experimental results agreed with one another. Strain proved to be capable of enhancing the anti-Stokes emission, suggesting that the efficiency of laser cooling may be improved by strain engineering.展开更多
We investigate the gravitational wave spectrum originating from the cosmological first-order phase transition.We compare two models:one is a scalar field model without gravitation,while the other is a scalar field mod...We investigate the gravitational wave spectrum originating from the cosmological first-order phase transition.We compare two models:one is a scalar field model without gravitation,while the other is a scalar field model with gravitation.Based on the sensitivity curves of the LISA space-based interferometer on the stochastic gravitational-wave background,we compare the difference between the gravitational wave spectra of the former and the latter cases obtained from the bubble collision process.In particular,we numerically calculate the speed of the bubble wall before collision for the two models.We demonstrate that the difference between the amplitudes of these spectra can clearly distinguish between the two models.We expect that the LISA with Signal to Noise Ratio=10 could observe the spectrum as the fast first-order phase transition.展开更多
基金This project is supported by Energy Research Corp., USA.
文摘The sol-gel process, sing aqueous solutions, is used for dip coating ontosubstrates of 316L stainless steel. A suitable coating of Li CoO_2 is achieved by varying thethickness and heat treating at 650 deg C for 3 h. Thermal analysis, X-ray diffraction analysis andSEM are carried out to characterize the microstructure of the coatings. The results show that thecoating transforms from an amorphous gel to crystalline phases above 350 deg C, and show a porousstructure. The phase transition mechanism is discussed.
文摘We consider a bistable mesoscopic chemical reaction system and calculate entropy produc- tion along the dominant pathway during nonequilibrium phase transition. Using probability generating function method and eikonal approximation, we first convert the chemical master equation into the classical Hamilton-Jacobi equation, and then find the dominant pathways between two steady states in the phase space by calculating zero-energy trajectories. We find that entropy productions are related to the actions of the forward and backward dominant pathways. At the coexistence point where the stabilities of the two steady states are equiv alent, both the system entropy change and the medium entropy change are zero; whereas at non-coexistence point both of them are nonzero.
文摘The heat and mass transfer characteristics under frosting on surface of heat exchanger were experimentally investigated in different conditions of air temperature, relative humidity, and face velocity. The heat transfer and heat transfer coefficient decreased faster with the high relative humidity, low air temperature and initial face velocity. The air pressure drop rose faster with the high relative humidity and low air velocity.
基金supported by the National Natural Science Foundation of China(No.22201120)。
文摘Molecular-based ferroelastics with dielectric switching properties are highly desirable for their applications on microelectronic dielectric switches,sensors,data storage,and so on.However,the current reports mostly focus on organic-inorganic hybrids containing toxic heavy metal atoms,and the relatively low phase transition temperature limits their application.In this paper,low-toxic organic salt ferroelastic enantiomers(R/S)-4-fluoro-1-azabicyclo[3.2.1]octonium chloride[(R/S)-F-321]were designed and synthesized under the introducing chirality strategy.They undergo a 432F422-type ferroelastic phase transition with a high Curie temperature(Tc)of 470 K,simultaneously exhibiting excellent dielectric switching characteristics.In addition to the ordered-disordered movement of cations,the significant displacement of anions is also responsible for such high Tc and large dielectric switching ratios,which is very rare in molecular-based switching materials.This work enriches the development of molecular ferroelastic switching materials and gives inspiration for the exploration of environmentally friendly high Tc organic salt ferroelastics with prominent switching performances.
基金supported by the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(No.22KJB510014)the Research Start-up Fund of Huaiyin Institute of Technology(No.Z301B20514)+3 种基金Foundation of Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province(Nos.HPK202102,HPK202303,HPZ202201)Open Project Foundation of National&Local Joint Engineering Research Center for Mineral Salt Deep Utilization(No.SF202306)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX23_1851)Huaian Talent Funding for Outstanding Doctors in Universities(Nos.Z302J22517,Z302J22518)。
文摘The existence of adsorbed water and structural water in the crystal structure of attapulgite(ATP)endows it with poor capability to store lithium ions.Herein,the chloride molten salt method was developed to function ATP materials based on theoretical calculations,which exhibit ground-breaking electrochemical performance.After the modification process,the metal ions in chloride molten salt occupy the vertices of the Mg-O octahedral structure from the liberation of structural water and hydroxyl groups in ATP,forming MaMgbAlcSixOy(M=Li,Na,or K).Using Li Cl molten salt-modified ATP(Li-ATP)as a proof-of-concept,the detailed phase transition,physicochemical properties,and lithium storage capacity were investigated.Compared to the original ATP,Li-ATP achieves a nearly 7-fold increase in lithium storage capacity(498mAh/g),featuring a promising low-cost polyanionic type anode material.
文摘Strain engineering provides an effective mean of tuning the fundamental properties of semiconductors for electric and optoelectronic applications. Here we report on how the applied strain changes the emission properties of hetero- structures consisting of different crystalline phases in the same CdS nanobelts. The strained portion was found to produce an additional emission peak on the low-energy side that was blueshifted with increasing strain. Furthermore, the additional emission peak obeyed the Varshni equation with temperature and exhibited the band-filling effect at high excitation power. This new emission peak may be attributed to spatially indirect exciton recombination between different crystalline phases of CdS. First-principles calculations were performed based on the spatially indirect exciton recombination, and the calculated and experimental results agreed with one another. Strain proved to be capable of enhancing the anti-Stokes emission, suggesting that the efficiency of laser cooling may be improved by strain engineering.
基金BHL(2020R1F1A1075472),DY(2021R1C1C1008622,2021R1A4A5031460)WL(2016R1D1A1B01010234)were supported by the National Research Foundation of KoreaLY was supported by the Basic Science Research Program(2020R1A6A1A03047877)of the National Research Foundation of Korea funded by the Ministry of Education through Center for Quantum Spacetime(CQUeST)of Sogang University。
文摘We investigate the gravitational wave spectrum originating from the cosmological first-order phase transition.We compare two models:one is a scalar field model without gravitation,while the other is a scalar field model with gravitation.Based on the sensitivity curves of the LISA space-based interferometer on the stochastic gravitational-wave background,we compare the difference between the gravitational wave spectra of the former and the latter cases obtained from the bubble collision process.In particular,we numerically calculate the speed of the bubble wall before collision for the two models.We demonstrate that the difference between the amplitudes of these spectra can clearly distinguish between the two models.We expect that the LISA with Signal to Noise Ratio=10 could observe the spectrum as the fast first-order phase transition.
