Abstract: Orthorhombic perovskitic metal-oxide superconductors of the lanthanum-barium-copper type (LaBa.sub.2 Cu.sub.3 O.sub.y) wherein Y ranges from 6.8 to 7.0, and T(R=O) is at least about 90.degree. K., can be prepared by sintering and annealing a substantially stoichiometric calcined mixture of one or more sources lanthanum, barium and copper under conditions wherein the time and temperature of exposure to oxygen during the sintering and annealing operations is controlled.

Abstract: Orthorhombic perovskitic metal-oxide superconductors of the lanthanum-barium-copper type (LaBa.sub.2 Cu.sub.3 O.sub.y) wherein Y ranges from 6.8 to 7.0, and T(R=0) is at least about 90.degree. K., can be prepared by sintering and annealing a substantially stoichiometric calcined mixture of one or more sources lanthanum, barium and copper under conditions wherein the time and temperature of exposure to oxygen during the sintering and annealing operations is controlled.

Abstract: The octane value of fuels such as gasoline is increased by adding thereto an organic compound containing a tert-butyl group bonded to a carbon or nitrogen atom, which, in turn, is bonded to yet another atom by double or triple bonds.

Abstract: The octane value of fuels such as gasoline is increased by adding thereto an organic compound containing a tert-butyl group or a radical containing a trimethyl silyl group bonded to a carbon or nitrogen atom, which, in turn, is bonded to yet another atom by double or triple bonds.

Abstract: The octane requirement increase phenomenon in a spark ignition internal combustion engine is controlled by introducing with the combustion charge a fuel composition containing an octane requirement increase-inhibiting amount of a compound selected from the group consisting of fused aromatics having at least 2, preferably between 3 and 5, aromatic rings with no heteroatoms substituted in the rings. The polynuclear aromatics can be either unsubstituted or substituted with groups other than an alkyl group. Usually the polynuclear aromatic is added to the fuel in an amount between about 0.1 and 5.0 weight percent of the fuel. In particular, anthracene and phenanthrene, and their non-alkyl derivatives, provide effective octane requirement increase-inhibiting additives for unleaded gasoline.

Abstract: Liquid hydrocarbon fuels having an enhanced cetane number include at least one azo compound having the formula:R.sub.1 N.dbd.NR.sub.2wherein R.sub.1 and R.sub.2 are the same or different organo groups, each containing 1 to about 10 carbon atoms.

Abstract: The octane requirement increase phenomenon in a spark ignition internal combustion engine is controlled by introducing with the combustion charge a fuel composition containing an octane requirement increase-inhibiting amount of a compound selected from the group consisting of fused aromatics having at least 2, preferably between 3 and 5, aromatic rings with no heteroatoms substituted in the rings. Usually the polynuclear aromatic is added to the fuel in an amount between about 0.1 and 5.0 weight percent on the fuel. In particular, anthracene and phenanthrene, provide effective octane requirement increase-inhibiting additives for unleaded gasoline.

Abstract: A fuel composition containing an acid anhydride as an anti-knock additive.

Abstract: A fuel composition containing a malonate as an anti-knock additive.

Abstract: A fuel composition containing an alkyl phenyl carbonate as an anti-knock additive.