Croatica Chemica Acta, Vol. 48 No. 4, 1976.
Izlaganje sa skupa
An Investigation of the Mechanism of Water Molecules Interaction with Hydrophilic Disperse Substances by the NMR Method
0. D. Kurilenko
; Institute of Colloid Chemistry and Water Pollution Control, Academy of Sciences of the Ukranian SSR, Kiev, USSR
V . V. Mank
; Institute of Colloid Chemistry and Water Pollution Control, Academy of Sciences of the Ukranian SSR, Kiev, USSR
Sažetak
The paper presents the results of an investigation of the linewidths
and chemical shifts of, the NMR of protons of water molecules
and some magnetic nuclei of counterions (Li+, F-, NH4+, H+)
in aqueous dispersions of a number of ion-exchange resins and
alumosilicates in solutions of high-molecular compounds. The
spectra have been recorded by the high-resolution NMR type
INM-4H-100 spectrometer with a 100 MHz work frequency for
protons and 40 MHz for 7Li in a wide temperature range from
173 K to 373 K.
The phenomenon that the shift of water ·signal versus tern-
. perature variation is smaller for electrolyte solutions that for
pure water, is proposed to be utilized for the evaluation of the
hydratation numbers of ions in electrolyte solutions. The activation
energy of molecular motion at low temperatures, calculated, from
temperature dependence of the linewidth is 8-16 kcal moi-1 and
it is in good agreement with the results obtained by other techniques.
A model of interaction of water molecules between each other
and with the active centres ·Of hydrophilic disperse systems has
been proposed. The peculiarities of the interaction of water molecules
with ions of various electron structure have been elucidated.
The hydratation numbers of counterions have been determined and
compared with those for equeous solutions of corresponding salts.
The special features of water molecules on the interface at low
temperatures have been discussed. The role of hydrogen bonds
in the determination of the freezing temperature of water has been
elucidated.
Ključne riječi
Hrčak ID:
196442
URI
Datum izdavanja:
22.12.1976.
Posjeta: 426 *