  Quantum correlations are investigated theoretically in a two-spin system with
the dipole-dipole interactions in the NMR multiple-pulse spin-locking
experiments. We consider two schemes of the multiple-pulse spin-locking. The
first scheme consists of $\pi/2$-pulses only and the delays between the pulses
can differ. The second scheme contains $\varphi$-pulses ($0<\varphi<\pi$) and
has equal delays between them. We calculate entanglement for both schemes for
an initial separable state. We show that entanglement is absent for the first
scheme at equal delays between $\pi/2$-pulses at arbitraty temperatures.
Entanglement emerges after several periods of the pulse sequence in the second
scheme at $\varphi=\pi/4$ at milliKelvin temperatures. The necessary number of
the periods increases with increasing temperature. We demonstrate the
dependence of entanglement on the number of the periods of the multiple-pulse
sequence. Quantum discord is obtained for the first scheme of the
multiple-pulse spin-locking experiment at different temperatures.
