Alkol-Su Karışımlarının Durulma Sürelerinin NMR Tekniği ile İncelenmesi

Nükleer manyetik rezonans (NMR), spin örgü (T1) ve spin-spin (T2) durulma zamanları ölçümleri sayesinde alkol-su karışımlarının moleküler dinamiği konusunda önemli bilgiler vermesinden dolayı önemli bir tekniktir. Bu çalışmada, durulma sürelerini ölçmek için iki farklı proton NMR cihazı kullanılmıştır: Bruker Minispec mq-20 zaman boyutlu NMR ve yüksek çözünürlüklü 42MHz’lik Magritek Spinsolve NMR. Etanol-su ve metanol-su karışımlarının T1 ve T2 değerleri, saf sudan saf alkole kadar değişen konsantrasyonlarda ölçülmüştür. Her iki cihaz tarafından elde edilen sonucun birbiriyle aynı eğilimde olduğu açıkça görülmektedir. Elde edilen etanol-su ve metanol-su karışımlarının hacimsel oranları sırasıyla 43% ve 44% olduğunda her iki tip durulma zamanlarında minimum gözlemlenmektedir.

Anahtar Kelimeler:

NMR, Spin-spin durulma süresi, Spin-örgü durulma süresi, Alkol-su karışımları

Investigation of Relaxation Times of Alcohol-Water Mixtures by Time Domain NMR Technique

Nuclear magnetic resonance (NMR) is important technique to probe the molecular dynamics of alcoholwater mixtures by measuring their spin-lattice (T1) and the spin-spin relaxation time (T2). In this work, we used two different proton NMR devices to measure relaxation times: Bruker Minispec mq-20 timedomain NMR and 42MHz Magritek Spinsolve high-resolution NMR. T1 and T2 of the ethanol-water and methanol-water mixtures measured for changing concentrations from pure water to pure alcohol.The results obtained by both devices are similar with each other. The minimal values of bothrelaxation parameters are observed at volume fractions of ethanol-water and methanol-water mixtures 43% and 44%, respectively

Keywords:

NMR, Spin-spin relaxation time, Spin-lattice relaxation time, Alcohol-water mixtures,

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