Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In thi...Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In this paper,the M-edge spectra of La ions and the M-edge,L-edge,and K-edge spectra of Mn ions in LaMnO3 are calculated by considering both the free-ion multiplet calculation and the crystal field effects.We analyze spectral shapes,identify peak origins,and estimate the oxidation states of La and Mn ions in LaMnO3 theoretically.It is concluded that La ions in LaMnO3 predominantly exist in the trivalent state,while Mn ions exist primarily in the trivalent state with a minor presence of tetravalent ions.Furthermore,the calculated spectra are in better conformity with the experimental spectra when the proportion of Mn3+is 90%and Mn4+is 10%.This article enhances our comprehension of the oxidation states of La and Mn within the crystal and also provides a valuable guidance for spectroscopic investigations of other manganates.展开更多
Using the theory shown, Cores Optimal Criterion, three factors from which hierarchical aggregation of variables under study was built, as well as hierarchical cores showing the level of use of pocket computing technol...Using the theory shown, Cores Optimal Criterion, three factors from which hierarchical aggregation of variables under study was built, as well as hierarchical cores showing the level of use of pocket computing technologies by students. The principal factors influencing the level of use of pocket computing technologies among higher education students are analyzed from a theoretical aggregation development based on hierarchical cores. The theoretical part includes the development of an algorithm used to obtain an interesting class or partition from a hierarchy. The experimental work carried out included design, preparation and application of a questionnaire to higher education students in Mexico. A pilot test was carried out to check timing and repetition of questions. Data was recorded, validated, and mathematically and statistically analyzed.展开更多
In this paper, we modeled a core/shell/shell structure with cylindrical Schrodinger-Poisson coupled equation when a magnetic field is (and is not) applied along its axis. We showed the electron density is peaked near ...In this paper, we modeled a core/shell/shell structure with cylindrical Schrodinger-Poisson coupled equation when a magnetic field is (and is not) applied along its axis. We showed the electron density is peaked near the outer surface of the channel when the magnetic field is applied. Therefore one may make a nano-device which its electrons move only on its outer surface. Also we applied a gate voltage to the device and showed a higher threshold voltage (to turn on the device) is necessary when a magnetic field is applied. This is because of the increase in the lowest energy level similar to the size quantization. i.e a device with longer channel looks like a device with shorter channel if it is placed in a magnetic field parallel to its axis.展开更多
There have been numerous studies of the photoelectron spectra （PES） on group ⅢA trimethyl compound MMe<sub>3</sub>（M=B, Al, Ga and In）. However, no reports on the theoretical Koopmans’ IPs have ever ...There have been numerous studies of the photoelectron spectra （PES） on group ⅢA trimethyl compound MMe<sub>3</sub>（M=B, Al, Ga and In）. However, no reports on the theoretical Koopmans’ IPs have ever been seen for MMe<sub>3</sub> except BMe<sub>3</sub>. In literature the assignment of the spectral band and the study on the electronic structure of M ’Me<sub>3</sub>展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11974253).
文摘Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In this paper,the M-edge spectra of La ions and the M-edge,L-edge,and K-edge spectra of Mn ions in LaMnO3 are calculated by considering both the free-ion multiplet calculation and the crystal field effects.We analyze spectral shapes,identify peak origins,and estimate the oxidation states of La and Mn ions in LaMnO3 theoretically.It is concluded that La ions in LaMnO3 predominantly exist in the trivalent state,while Mn ions exist primarily in the trivalent state with a minor presence of tetravalent ions.Furthermore,the calculated spectra are in better conformity with the experimental spectra when the proportion of Mn3+is 90%and Mn4+is 10%.This article enhances our comprehension of the oxidation states of La and Mn within the crystal and also provides a valuable guidance for spectroscopic investigations of other manganates.
文摘Using the theory shown, Cores Optimal Criterion, three factors from which hierarchical aggregation of variables under study was built, as well as hierarchical cores showing the level of use of pocket computing technologies by students. The principal factors influencing the level of use of pocket computing technologies among higher education students are analyzed from a theoretical aggregation development based on hierarchical cores. The theoretical part includes the development of an algorithm used to obtain an interesting class or partition from a hierarchy. The experimental work carried out included design, preparation and application of a questionnaire to higher education students in Mexico. A pilot test was carried out to check timing and repetition of questions. Data was recorded, validated, and mathematically and statistically analyzed.
文摘In this paper, we modeled a core/shell/shell structure with cylindrical Schrodinger-Poisson coupled equation when a magnetic field is (and is not) applied along its axis. We showed the electron density is peaked near the outer surface of the channel when the magnetic field is applied. Therefore one may make a nano-device which its electrons move only on its outer surface. Also we applied a gate voltage to the device and showed a higher threshold voltage (to turn on the device) is necessary when a magnetic field is applied. This is because of the increase in the lowest energy level similar to the size quantization. i.e a device with longer channel looks like a device with shorter channel if it is placed in a magnetic field parallel to its axis.
文摘There have been numerous studies of the photoelectron spectra （PES） on group ⅢA trimethyl compound MMe<sub>3</sub>（M=B, Al, Ga and In）. However, no reports on the theoretical Koopmans’ IPs have ever been seen for MMe<sub>3</sub> except BMe<sub>3</sub>. In literature the assignment of the spectral band and the study on the electronic structure of M ’Me<sub>3</sub>
