How to use tap water, electronic scales, plastic basin and towel rough measurement of heart volume

Answer:

Rare earth ions 4f electron energy ratio 5S, 5p track high, but 5S, 5p orbit outside, in orbit 4f and 5S, 5p on the track of electronic crystal field shielding, 4f electronic affected by the crystal field is greatly reduced. The 4f electrons of rare earth ions are much smaller than the Coulomb interaction between electrons, and are far less than the spin orbit of 4f electrons. Considering the Coulomb interaction and spin orbit interaction between electrons, the 4f electronic energy levels are represented by 2J+I LJ. The crystal field will make the level with total angular momentum quantum number J splitting strength and symmetry split form and depends on the size of the crystal field. This kind of rare earth ions 4f energy level splitting, on the surrounding environment (ligand, crystal field strength, symmetry) is very sensitive and can be used as a probe to study the crystal structure, the local environment of rare earth ions in amorphous materials, organic molecules and biological molecules, 2J+I and LJ level in different heavy heart crystals in roughly the same 4f, electronic luminescence of rare earth ions are characteristic, so it is easy to identify what line of rare earth ions in the light.

The crystal field theory holds that when the rare earth ions are doped into the crystal, the energy levels are different and the free ions are affected by the lattice ions in the vicinity. This effect comes mainly from the electrostatic field generated by the surrounding ions, commonly known as the crystal field [2]. The crystal field changes the splitting and transition probabilities of the ions. Rare earth ions form a typical discrete luminescent center in solid. In a discrete luminescence center, electrons participating in the luminescence transition are electrons forming the central ions themselves, and the transitions of electrons occur between the energy levels of the ions themselves. The luminescence properties of the center depend mainly on the ions themselves, while the influence of the lattice of the matrix is secondary.