Paraffins in Romashkino deposit oils (Republic of Tatarstan, Russian Federation) and oils from the асн-о deposit were examined using the pulse nuclear magnetic resonance relaxometry (NMRR) method (Vietnam). Romashkino oils, in which paraffin was dissolved, were utilised as study samples. Isoparaffin i-C22H46 was utilised (docozan). NMR relaxometer NMR-NP2 on resonance frequency o = 18,45 MHz was used to determine NMR structure-dynamical characteristics such as spin-lattice T1i, spin-spin T2i relaxation periods, and their proton phases P1i and P2i. Relaxation times of the spinlattice T1A(ms) and spin-spin T2A,B (ms) from inverse temperature 103/T K and time t A cooling period of (minutes) was observed. They are described by equations with a regression coefficient of R2 = 0.94, and show spasmotic 1,,C and 2,,C decreases with increasing temperature, with jumps in their levels approaching 20%. So were disclosed the processes of structure-dynamical (SD) ordering, which can be thought of as a long-term hardening phase transition with activation energies EAi through a series of stage exo/endothermic local phase transitions with the formation/melting of a temporary ordered state. Obviously, it has something to do with paraffin ordering. The relaxation times increased after 2 minutes of super high frequency (SHF) irradiation at frequency = 2.45 GHz and power P = 180W. A cooling period of (minutes) was experienced. They are described by equations with a regression coefficient of R2 = 0.94, and show spasmotic 1,,C and 2,,C decreases with temperature rise, with jumps in their values up to 20%. So were disclosed the processes of structure-dynamical (SD) ordering, which can be thought of as a long-term hardening phase transition with activation energies EAi through a series of exo/endothermic local phase transitions with the formation/melting of a temporary ordered state. It's clear that it has something to do with paraffin ordering. The relaxation times increased after 2 minutes of super high frequency (SHF) irradiation at 2.45 GHz with power P = 180W. A cooling period of (minutes) was experienced. They are described by equations with a regression coefficient of R2 = 0.94, and show spasmotic 1,,C and 2,,C decreases with temperature rise, with jumps in their values up to 20%. So were disclosed the processes of structure-dynamical (SD) ordering, which can be thought of as a long-term hardening phase transition with activation energies EAi through a series of exo/endothermic local phase transitions with the formation/melting of a temporary ordered state. It's clear that it has something to do with paraffin ordering. The relaxation times increased after 2 minutes of super high frequency (SHF) irradiation at 2.45 GHz with power P = 180W.
ii) Below this temperature range Т2B of B proton phase has an uneven
behavior with oscillations Wesuppose they are caused by structure-dynamical processes
of temporal ordering of paraffin molecules before the final crystallization, at
which Т2B falls to value Т2B = 6.3 ms.
iii) For relaxation times Т2А of А proton phase the decrease of Т2А with three clear extremes (minimums) of Т2А were observed. Probably they related to three-stage process of pre crystallization ordering of –CH2-CH3- groups. Then was observed oscillations Т2А which ended with the full crystallization of phase А and sharp fall of Т2А. State of paraffin in this range may be named as “rigidlattice” state.
iiii) In the melt state of paraffine proton phase A population has value P2А = 65%. At the temperature of the full cooling its value reach value Р2А = 98%, which is the evidence that at low temperatures main contribution in relaxation descend from the end –CH3 chains. Molecular fragments of B phase have We linked these 2i anomalies to SD phase transitions, which happen as a result of transitory (dynamical) production and subsequent melting of supermolecular structure clusters on the paraffin base. They are complemented in our case by structure ordering, which is accompanied by a decrease in interatomic distances Rij in structure units. This is an exo/endothermic process, with the latter resulting in a negative local C. It is a manifestation of open dissipative systems aspire to the lowest possible temperature. the free energy and entropy with more sufficient decrease of the enthalpy H contributing in ЕАSD, than entropy S decrease (▵H < 0, ▵S < 0, |▵H} > |▵S|), which gives negative ЕАSD = ▵H - T▵S < 0.
Author (s) Details
O. V. Kozelkov
Kazan State Power Engineering University, Kazan, Tatar Republic of Russian Federation, Russia.
R. S. Kashaev
Kazan State Power Engineering University, Kazan, Tatar Republic of Russian Federation, Russia.
B. R. Safiullin
Kazan State Power Engineering University, Kazan, Tatar Republic of Russian Federation, Russia.
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