Perfluorocarbons density

Initial efforts focused upon the ability of ultrasound to aid in the translation of nanodroplets in an aqueous medium. We have determined that 2% perfluorocarbon nanodroplets were easily translated through an aqueous medium out of the blood flow by radiation force/microstreaming methodology. As expected, the translation of the nanodroplets varied inversely as a function of perfluorocarbon density (i.e. translation perfluoropentane > perfluorohexane > perfluoroheptane > perfluorooctane > PFOB, density perfluorooctane > perfluoroheptane > perfluorohexane... 

The first heavier than water internal tamponade was introduced in 1987 by Chang with LPFC [1]. The two perfluorocarbons most used are perfluorooctane and perfluorodecaline. Perfluorotributylamine, perfluoropolyether, perfluorooctyl-bromide and perfluorophenanthrene are less used. LPFC are transparent fluids and are not miscible in water and their main characteristic is their high density (1.76-2.03) [2], Their properties are summarised in Table 1. 

The density of the perfluorocarbons is usually more than twice that of their hydrocarbon counterparts. The low dielectric constants, surface/interface tensions and refractive indices of perfluorocarbons reflect their nonpolar character as liquids and solvents.6... 

The plasma probe method can be used to determine the electron temperature and the electron density of plasma. The quantitative value of the method has been an academic point of argument among investigators however, the qualitative indication of the presence of negative ions obtainable by the method seems to be very valuable for the interpretation of the plasma polymerization of perfluorocarbons. 

The paramagnetic absorption of alkane radical cations is critically dependent on their conformation. In neat n-alkane crystals, alkane molecules are in the extended all-trans conformation (see Fig. 5.1) and FDMR spectroscopy unequivocally shows that alkane radical cations retain that conformation in such systems. The extended all-trans conformation is also the preferred conformation of many n-alkane radical cations in chlorofluorocarbon and perfluorocarbon matrices. In this conformation, the unpaired electron occupies the planar cr molecular orbital and delocalizes over the entire extended chain. Only two C-H bonds (both chain-end, one on each side) are in the planar ct molecular frame in the extended structure and high unpaired-electron and positive-hole density appears only on these in-plane protons. Alkane radical cations in the extended conformation (as well as in other conformations) are thus fj-delocalized paramagnetic species. The associated hyperfme interaction with the two (equivalent) in-plane chain-end protons results in a 1 2 1 three-line (triplet) EPR spectrum. The fact that the hyperfme in-... 

In addition to evaluating the behavior of perfluorooctane-coated electrodes at room temperature, experiments were also performed at 55 C under similar conditions, as shown in Fig. 1.24. A similar type of rate enhancement was observed with perfluorocarbon treated electrodes at high current densities at 55 °C, although no loss in activity was seen at the lower current densities in contrast to the room temperature experiments. A significant... 

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