Abstract: Novel di(poly-substituted cyclopentadienyl)-allylic uranium complexes can be employed to catalyze the dimerization of propylene to form 4-methyl-1-pentene selectively. The novel catalyst complexes can be prepared from novel di(poly-substituted cyclopentadienyl)-U(IV) monohalo monoallylic complexes.

Abstract: A proces for regenerating a spent catalyst comprising uranium and a poly-substituted cyclopentadienyl ligand comprising contacting the deactivated catalyst with hydrogen under reaction conditions. The regenerated catalyst is active in the selective dimerization of propylene to 4-methyl-1-pentene.

Abstract: A battery charger system is provided in which a microprocessor is used to discontinue application of a high charge current when the battery voltage drops below a peak value by a value greater than a threshold value corresponding to stored digital data. The microprocessor is also used to obtain a discharge mode of operation and an autocycle mode of operation in which a charge operation is performed after a discharge operation, the microprocessor being responsive to actuation of keys of a keyboard. In performing various operations, the microprocessor is used in performing analog-to-digital conversions and it is additionally used in computing energy capacity and efficiency.

Abstract: Uranium di(poly-substituted cyclopentadienyl)-hydride complexes, as well as certain uranium (IV) and rare earth metal complexes, can be employed to catalyze the dimerization of propylene to form selectively 4-methyl-1-pentene.

Abstract: The invention is a selective process for preparing 1,1,1-trichloroethane comprising irradiating a vaporous mixture comprising 1,1-dichloroethane, chlorine and an effective amount of a photocatalyst wherein the photocatalyst is bromine, a compound which liberates bromine in the presence of chlorine, carbon monoxide, nitric oxide or oxygen, with radiation capable of inducing the selective formation of 1,1,1-trichloroethane. Radiation in the wavelength of between about 250 and 550 nanometers is capable of inducing the selective formation of 1,1,1-trichloroethane.

Abstract: Improved ringer signal circuitry in a telephone handset modifies the leading edge of the ringer signal envelope causing ringer volume to gradually increase, over a period of time, to its maximum value.