H-hexadecane

Counting efficiencies were based on determinations of n-( H) Hexadecane (standard batch nr 20, The Radiochemical Centre,... 

For the F-66E/PFHB emulsion, Tcr was estimated to be about 12 min, in close agreement with the rapid mass transfer observed experimentally. Excellent agreement with experiment was also observed for the molecular diffusion of perfluoro-octyl bromide (Tcr 3 h), hexadecane (rcR 520 h), and the absence of ripening observed for triolein (Tcr w 4 years) emulsions. 

Fig. 8—Effective viscosity of confined hexadecane measured on SFA as a function of shear rate and film thickness, from which it is seen that the shear thinning gradually disappears as the film thickness increases and the viscosity finally has approached the bulk values at h=122 nm.

When the polar additive nonylic acid was added into hexade-cane liquid, the contact ratio becomes much smaller than that of pure hexadecane, which is shown in Fig. 39. For hexa-decane liquid, the critical speed to reach zero contact ratio is 50 mm/s, which is much higher than that of mineral oil 13604 because of its much lower viscosity. Flowever, when nonylic acid was added into the hexadecane liquid, the critical speed decreased from more than 50 mm/s to 38 mm/s. The same phenomenon can be seen in Fig. 39(h) which shows the comparison of oil 13604 and that added with 1.8 %wt. nonylic acid. The addition of polar additive reduces the contact ratio, too, but its effect is not as strong as that in hexadecane liquid because the oil 13604 has a much larger viscosity. Therefore, it can be concluded that the addition of polar additives will reduce the contact ratio because the polar additives are easy to form a thick boundary layer, which can separate asperities of the two rubbing surfaces. 

The FTE SAMs have a good hydrophobic property. Ohio et al. [36] have compared the variation of contact angles with immersing time in a neat FTE and a 100 mM FTE solution. The contact angles of water and hexadecane increased to about 110° and 73° from the initial value 76° and 36°, respectively, after 24 h immersion. Their works also indicate that the adsorption rate in 100 mM FTE solution is slightly faster than that in neat FTE. 

Asperger O, A Nanmann, H-P Kleber (1981) Occnrrence of cytochrome P-450 in Acinetobacter strains after growth on n-hexadecane. FEMS Microbiol Lett 11 309-312. 

MD simulations in expHcit solvents are stiU beyond the scope of the current computational power for screening of a large number of molecules. However, mining powerful quantum chemical parameters to predict log P via this approach remains a challenging task. QikProp [42] is based on a study [3] which used Monte Carlo simulations to calculate 11 parameters, including solute-solvent energies, solute dipole moment, number of solute-solvent interactions at different cutoff values, number of H-bond donors and acceptors (HBDN and HBAQ and some of their variations. These parameters made it possible to estimate a number of free energies of solvation of chemicals in hexadecane, octanol, water as well as octanol-water distribution coefficients. The equation calculated for the octanol-water coefficient is ... 

Finke, H.L., Gross, M.E., Waddington, G and Huffman, H.M. Low temperature thermal data for the nine normal paraffin hydrocarbons from octane to hexadecane, J. Am. Chem. Soc., 76(2) 333-341,1954. 

Very limited animal data indicate that kerosene is absorbed and distributed to various tissues (Mann et al. 1977). Kerosene, labelled with H-toluene or C-hexadecane, was given to tracheotomized baboons (15 mL/kg) by nasogastric tube (Mann et al. 1977). Radioactivity was recovered from the brain, lung, liver, spleen, heart, and kidney after 6 hours. H-Toluene was absorbed and taken up by most tissues to a greater extent than was C-hexadecane however, the amounts absorbed and distributed were very small (Mann et al. 1977). 

In the same way, o-nitrophenyl octyl ether (o-NPOE) was immobilized on polycarbonate (PC) filters and the apparent permeability measured after 5 h incubation time was correlated to log Pnpoe for a series of reference compounds (log Pnpoe ranging from —1 to 3.6) [90]. Lipophilicity values in the alkane/water system were also determined using PAMPA with hexadecane-PC coated filters [89]. In this case, a correlation was found between intrinsic permeability (log Pq, permeability corrected for ionization and for unstirred water layer contribution, which particularly affects permeability of lipophilic compounds) and log P ik. However, log Pq is obtained from the knowledge of the pJC, value(s) and the permeability pH profile and therefore requires the full permeability pH profile to be measured for each compound, which negatively impacts the assay throughput. 

A very interesting synthetic method of bicyclo[n.l.O]alkanes from cychc ketones via this 1,3-C,H insertion of magnesium carbenoid as a key reaction was reported (equation 22) . 1-Chlorovinyl p-tolyl sulfoxide (76) was synthesized from cyclopentadecanone and chloromethyl p-tolyl sulfoxide in three steps in high overall yield. Lithium enolate of tert-butyl acetate was added to 76 to give the adduct 77 in quantitative yield. a-Chlorosulfoxide (77) in a toluene solution was treated with i-PrMgCl in ether at —78 °C and the reaction mixture was slowly warmed to 0°C to afford the bicyclo[13.1.0]hexadecane derivative 79 in 96% yield through the reaction of the intermediate magnesium carbenoid 78. 

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