Abstract: Fluid flow through a conduit is selectively blocked upon the occurrence of an alarm condition by an inflatable member normally folded when not in use to occupy as small a volume as is practicable. The small size volume together with securement of the inflatable member in a preferred location minimizes the effect of the inflatable member to normal fluid flow. A thin, tear-away sleeve maintains the inflatable member in the folded state and quickly tears apart during inflation enabling the inflatable member to fill and plug the interior of the conduit. The shape of the inflatable member, together with the fluid source utilized for inflation assures rapid, liquid-tight sealing. Alarm signal monitoring and inflation initiation is guaranteed under substantially all conditions through the employment of an electronic controller with a stand-by battery.

Abstract: Hydrocarbon fuel compositions containing at least one divalent tetracoordinated cobalt compound represented by the structure ##STR1## wherein: R.sub.1, R.sub.2 and R.sub.3 are each independently selected from hydrogen and C.sub.1-6 alkyl, andR.sub.4 is a branched C.sub.3-6 alkyl wherein the branching is on either or both of the number 1 and 2 carbon atoms of said alkyl group.

Abstract: Hexacoordinated transition metal compounds and fuel compositions containing them, said compounds represented by the structure ##STR1## wherein: M is selected from at least one member of the group Mn, Fe, Co and Ni,R.sub.1 and R.sub.2 are hydrocarbyl groups of 1 to 6 carbon atoms,R.sub.3 is hydrogen or an alkyl of 1 to 6 carbon atoms,R.sub.4 and R.sub.5 are hydrogen or alkyl of 1 to 4 carbon atoms, andA is a divalent hydrocarbyl group of 2 to 10 carbon atoms selected from a member of the group alkylene, phenylene and cycloalkylene, each member providing 2 or 3 carbon atoms between the nitrogen atoms with the proviso that when A is phenylene the number of carbon atoms between the nitrogen atoms is 2.

Abstract: Hexacoordinated transition metal compounds, useful as antiknocks, having the structure ##STR1## wherein M is a divalent metal selected from the group Mn, Fe, Co and Ni,L.sub.1 and L.sub.2 are the same or different chelate-forming .beta.-diketone groups having from 5 to 20 carbon atoms, one or both of L.sub.1 and L.sub.2 having at least one polyfluoroalkyl group, --CF.sub.2 X, adjacent to the carbonyl group,X is selected from the group H, F, Cl, phenyl, C.sub.1 -C.sub.6 alkyl and C.sub.n F.sub.2n Y,n is 1 to 6,Y is H, F, or Cl,L.sub.3 is a ligand having the structure A-Z-B,whereinA and B are the same or different members of the group --NH.sub.2, --NHR.sub.5, --NR.sub.5 R.sub.6, OH, OR.sub.5, SH, SR.sub.5 and PR.sub.5 R.sub.6,R.sub.5 and R.sub.6 are the same or different members of the group C.sub.1 to C.sub.