Документ взят из кэша поисковой машины. Адрес оригинального документа : http://ofvp.phys.msu.ru/en/science_education/diploma/annot/2012/Farizanov_Arakcheev_en.pdf Дата изменения: Wed Dec 21 16:18:20 2011 Дата индексирования: Mon Oct 1 21:48:59 2012 Кодировка:

Transformation of spectral profiles of carbon dioxide at adsorption in nanopores near the critical temperature.

The work is focused on the analysis of behavior of carbon dio xide vibrat ional spectra at isothermal adsorption in pores of nanoporous glasses at near-crit ical temperatures. Experimental data obtained at several temperatures (including near-crit ical) for 4 and 7 nm diameter pores was used. Calculat ions of spectra were performed using the concept of surface adsorption and capillary condensat ion. The spectral contributions of gas, adsorbed layers, and condensed phase inside the pore volume were assumed to be proportio nal to the mass fraction. At 20.5 22.3 oC which are far enough from crit ical value 31.1 , the results of calculat ions are in a good agreement with experimentally observed transformat ion of spectrum fro m Lorentzian (at relat ively low pressures) to evident two-component line shape at approaching the saturation pressure. In the case o f near-critical temperature 30.5 , the analysis of experimental data and calculat ions shows that carbon dioxide turns into the condensed phase inside the pores at abnormally low pressures. Moreover, at supercrit ical temperature 33 the interface (impossible in bulk) between gaseous and condensed phase also appears inside the pores. The est imat ions o f the surface tensio n coefficients at the sub- and supercritical temperatures were carried out.