Monotone sequences are constructed that converge to the ex tremal solutions of second order three point boundary value problems when the functions involved do not possess any monotone properties.
The vibrational modes of BaTiO3 in different crystalline phases have been investigated by means of density functional theory pseudo potential method.The evidence of tetragonal to orthorhombic and orthorhombic to rhomb...The vibrational modes of BaTiO3 in different crystalline phases have been investigated by means of density functional theory pseudo potential method.The evidence of tetragonal to orthorhombic and orthorhombic to rhombohedral phase transitions present for 8 nm BaTiO3 ceramics further demonstrates that the similar successive transitions in 8 nm BaTiO3 ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions are as those in coarse BaTiO3 ceramics.展开更多
Isotropic negative permeability composite,composed of BST-MgO dielectric cubes with high permit-tivity dispersed in the Teflon substrate with low permittivity,was designed and fabricated based on Mie resonance and the...Isotropic negative permeability composite,composed of BST-MgO dielectric cubes with high permit-tivity dispersed in the Teflon substrate with low permittivity,was designed and fabricated based on Mie resonance and the effective medium theory.Measurements and simulations showed that the dielectric composite exhibited a strong sub-wavelength magnetic resonance at the first Mie resonance and possessed isotropic negative permeability,which resulted from the displacement current excited in the cubes.The dielectric particle was equivalent to a magnetic dipole at the magnetic resonance,which could be adjusted by the size and permittivity of the particles.It may provide a convenient method to design isotropic metamaterials and invisible cloak at infrared and visible frequencies.展开更多
文摘Monotone sequences are constructed that converge to the ex tremal solutions of second order three point boundary value problems when the functions involved do not possess any monotone properties.
基金supported by the National Basic Research Program of China(2002CB613301)the National Natural Science Foundation of China(50872094)Hainan University Research Fund
文摘The vibrational modes of BaTiO3 in different crystalline phases have been investigated by means of density functional theory pseudo potential method.The evidence of tetragonal to orthorhombic and orthorhombic to rhombohedral phase transitions present for 8 nm BaTiO3 ceramics further demonstrates that the similar successive transitions in 8 nm BaTiO3 ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions are as those in coarse BaTiO3 ceramics.
基金the National Natural Science Foundation of China (Grant Nos.50425204,50632030,60608016,10774087)the State Key Laboratory of Tribology (Grant No. SKLT 08B12)
文摘Isotropic negative permeability composite,composed of BST-MgO dielectric cubes with high permit-tivity dispersed in the Teflon substrate with low permittivity,was designed and fabricated based on Mie resonance and the effective medium theory.Measurements and simulations showed that the dielectric composite exhibited a strong sub-wavelength magnetic resonance at the first Mie resonance and possessed isotropic negative permeability,which resulted from the displacement current excited in the cubes.The dielectric particle was equivalent to a magnetic dipole at the magnetic resonance,which could be adjusted by the size and permittivity of the particles.It may provide a convenient method to design isotropic metamaterials and invisible cloak at infrared and visible frequencies.
基金supported by the National Natural Science Foundation of China(Grant Nos.50425204,50272032&90401012)the Ministry of Sciences and Technology of China through 973-Project(Grants 2002CB61306&2001CB6104).