The six nanosized PrF3 samples were synthesized using two different chemical reactions and different time of hydrothermal reaction. The X-ray and HRTEM experiments showed high crystallinity of synthesized samples. For all samples the particles size d
istribution was obtained. It was shown, that precursors of chemical reaction have influence on the shape of synthesized nanoparticles. The size of nanoparticles depended on the time of hydrothermal reaction as much as roughly 10 nm per hour.
At the present work we propose a new method for studying the processes of thermodynamic equilibrium setting in the adsorbed 3He film in a porous media. By this method we have studied the thermalization of the adsorbed 3He on the silica aerogel surfac
e at the temperature 1.5 K. The process of the thermodynamic equilibrium setting was controlled by measuring of the pressure in the experimental cell, the amplitude of the NMR signal and the time of the nuclear spin-spin and spin-lattice relaxation times of an adsorbed 3He. The thermodynamic equilibrium setting in the system adsorbed helium-3 - aerogel has the characteristic time 26 min.
Two nanosized PrF3 samples were synthesized using two different procedures. The X-ray and HRTEM experiments showed high crystallinity of synthesized sample. Comparison of enhanced 141Pr NMR spectra of microsized (45 $mu$m) and nanosized PrF3 powder i
s presented. Experimental data on spin kinetics of 3He in contact with PrF3 nanoparticles at T = 1.5 K are reported.
