In fact, the chemical behaviour of these two elements is more similar than for any other pair of elements known.
In a Banach algebra, the spectrum satisfies σ ab)∖{0}="σ(ba)∖{0} for each pair of elements a,b.
The first is a pair of elements called temporal gates that 'observe' electric fields in ultrashort time windows — the two observations differ by a time delay.
Also unique to lissamphibians is the columella-opercular complex, a pair of elements associated with the auditory capsule that transmit airborne (columella) or seismic (operculum) signals.
The virtual identity of atomic and ionic sizes, resulting from the lanthanoid contraction, has the effect of making the chemical behaviour of these two elements more similar than for any other pair of elements known.
A balanced incomplete block design (BIBD) B[k,λ υ] is an arrangement of υ elements in blocks of k elements each, such that every pair of elements is contained in exactly λ blocks.
A directed covering design, DC v, k, λ), is a (v, k, 2λ) covering design in which the blocks are regarded as ordered k-tuples and in which each ordered pair of elements occurs in at least λ blocks.
When the heat flux is fixed at 20,000 Wm−2 along with the temperature difference of 40 °C, the output power and efficiency of a pair of elements can be increased to 7.99 mW and 9.52%, respectively.
For a pair of elements in such that, put (2.1).
This is a total (called also linear) order, i.e., any pair of elements is comparable.
Every pair of elements of X has a lower bound or an upper bound.
