Rubbing-rolling

Both male and female coyotes, C. latrans, are attracted to volatile aldehydes from sheep liver and estrous urine of female coyotes. The most active compoimds were octanal, nonanal, decanal, and imdecanal. The aldehydes released sniffing and rub-rolling, but little lick-chewing and biting. Therefore, these compoimds are better suited to attract coyotes to traps than to toxicant-delivery systems that rely on the latter behaviors (Scrivnereta/., 1984). 

The O-ring can flex and roll - There is no need for the shaft to slide and rub under the o-ring while under an axial load. 

Similar results were reported by other investigators, [19,20], but attention was paid to investigating the effect of lubricant additives on the boundary film thickness. It is speculated that there should be no adsorbed layers formed on rubbing surfaces if purified and nonpolar lubricants are applied. The interferometer measurements show that in the case of using base oils, the relation between the film thickness and rolling speed follows the EHL power law pretty well down to 1 nm (Fig. 6(a)), or sometimes the film thickness may deviate from the Hamrock and Dowson s line and turn down quickly (Fig. 6(b)). If there is a small percentage of additives in the lubricant, on the other hand, the deviation from the power law occurs in a different way that the h-V... 

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