I can understand this limitation: it's not usually easy to superimpose a regular lattice of information upon an XML document; such is the mismatch between extensible hierarchies and rigid tables.

For this project is a heavier steel structure, plant production double-layer lattice rigid support scheme, the amount of steel per unit area save about 10%.

Part of lattice in rigid zeolites can be slackened by water molecules, the crystal lattice remains unchanged, but its space is increased.