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In cell biology, precursor cells—also called blast cells—are partially differentiated, or intermediate, and are sometimes referred to as progenitor cells. A precursor cell is a stem cell with the capacity to differentiate into only one cell type, meaning they are unipotent stem cells .
The unit cell is defined as the smallest repeating unit having the full symmetry of the crystal structure. [2] The geometry of the unit cell is defined as a parallelepiped, providing six lattice parameters taken as the lengths of the cell edges (a, b, c) and the angles between them (α, β, γ).
[2] For example, the matrix = transforms a primitive cell to body-centered. Another particular case of the transformation is a diagonal matrix (i.e., P i ≠ j = 0 {\textstyle P_{i\neq j}=0} ). This called diagonal supercell expansion and can be represented as repeating of the initial cell over crystallographic axes of the initial cell.
Blast waves have properties predicted by the physics of waves. For example, they can diffract through a narrow opening and refract as they pass through materials. Like light or sound waves, when a blast wave reaches a boundary between two materials, part of it is transmitted, part of it is absorbed, and part of it is reflected.
A primitive cell is a unit cell that contains exactly one lattice point. For unit cells generally, lattice points that are shared by n cells are counted as 1 / n of the lattice points contained in each of those cells; so for example a primitive unit cell in three dimensions which has lattice points only at its eight vertices is considered to contain 1 / 8 of each of them. [3]
Arc flash is distinctly different from the arc blast, which is the supersonic shockwave produced when the uncontrolled arc vaporizes the metal conductors. Both are part of the same arc fault, and are often referred to as simply an arc flash, but from a safety standpoint they are often treated separately.
Examples of compounds with this structure include sodium chloride itself, along with almost all other alkali halides, and "many divalent metal oxides, sulfides, selenides, and tellurides". [7] According to the radius ratio rule , this structure is more likely to be formed if the cation is somewhat smaller than the anion (a cation/anion radius ...
For example, a calcite(104) (2×1) reconstruction means that the unit cell is twice as long in direction a and has the same length in direction b. If the unit cell is rotated with respect to the unit cell of the nonreconstructed surface, the angle φ is given in addition (usually in degrees). This notation is often used to describe ...