Trapping success

Both the carbon-carbon and carbon-oxygen double bonds of fluoroketenes can take part in [2+2] cycloadditions, but with cyclopentadiene, only cyclo butanones are produced via concerted [2 +2 ] additions [J34] (equation 58) Cycloadditions involving the carbon-oxygen double bonds to form oxetanes are discussed on page 855 Difluoroketene is veiy short lived and difficult to intercept but has been trapped successfully by very electron rich addends to give 2 2 di fluorocyclobutanones m moderate yields [/55] (equation 59)... 

The unknown coefficients ajfc(f) are determined by our requiring equation (5.2.20) to be exact for 1,2,..., N traps successively. In this way we find that... 

Ill-defined concoctions have for centuries been used to lure muskrats in the USA, but we have looked in vain for published data which prove the effectiveness of these lures. Only one very brief statement by Williams (20) about the effectiveness of addition of "muskrat scent" to carrot-baited traps was found in the Journal of Wildlife Management of 1951. A table showed that the "average trapping success" increased from 23.6 to 42.8%, but the two series of experiments (controls and scented carrots) were not made simultaneously, so these results hardly prove the attractancy of the scent. 

The radical anion of molecular oxygen (O ) has been prepared and trapped in a range of alcohols, water and benzene but not in aliphatic hydrocarbons (Bennett et al., 1968a). In contrast to COg the e.s.r. spectrum shows that 0 interacts strongly with its immediate environment. This interaction which alters the separation of the upper molecular orbitals of the anion is strongly dependent on the nature of the matrix. Previously, the Oj" radical ion has been stabilized only in ionic materials such as the alkali halides thus it is of particular interest to find that this anion can be trapped successfully in a non-polar matrix (benzene). There is some evidence (Evans, 1961), from optical spectroscopic studies that molecular oxygen can form a weak charge transfer complex with the 77-electron system in benzene and it seems probable that O2 is stabilized in benzene by the formation of a similar complex. 

Tongne flicking behavior of snakes in response to odors from small mammals Effects of bait type and location on trapping success with deer mice Food choices of Norway rats Tadpole behavior in the presence of predatory fish... 

Pheromone Mass Trapping Successful Rebirth of an Old Idea... 

Dicyanobutadiene. On thermolysis, 1,2-dicyanocycIobutene is converted into 2,3-dicyanobutadiene, which slowly polymerizes. The butadiene, however, can be trapped successfully when generated in the presence of olefins, particularly electron-rich olefins. An example is the cycloaddition with indene (equation I). ... 

Pentamethylenevinylidene carbene has been generated by base catalyzed 7-elimination of HCl from 1-chloro-l-ethynylcyclohexane using dicyclohexyl-18-crown-6 or 18-crown-6 as phase transfer catalyst. This unsaturated carbene has been trapped successfully by styrene (40%, see Eq. 4.16), 2,5-dimethyl-2,4-hexadiene (36%), and iso-prene (32%) [26]. 

Relative capture success of clean and predator contaminated traps can be an indicator of avoidance. Stoddart (1976) assessed the effects of weasel odors on trap success in a mixed community of rodents. Two traps were placed at 10-m intervals on a 6 x 6 grid. Paired traps were placed as close as possible to each other and a pretreatment period indicated either trap was as likely as the other to capture a rodent. One trap in each pair then was randomly selected to be treated with weasel and gland secretion during the treatment period. Robinson (1990) found that trapping patterns made little difference in small mammal response to mink odors. Tests results were similar regardless of whether the traps were placed in pairs immediately adjacent to each other or in rows at 10-m intervals. Tobin et al. (1995) compared the capture rate of rats in traps known to have previously captured a mongoose to that of clean traps. 

---