The present invention provides materials with high bulk photovoltaic effect response. The present invention also provides for products comprising the high bulk photovoltaic effect materials of the present invention.

A cooling system for a ball mill used for production of a lead oxide is disclosed. The system has an internal nozzle configured to introduce water into an interior of a rotating ball mill drum, and a water conduit on an exterior of the rotating drum and configured for external water delivery so as to deliver water on the drum exterior. A control system may also be provided for control of the cooling system. A method is also disclosed.

A cooling system for a ball mill used for production of a lead oxide is disclosed. The system has an internal nozzle configured to introduce water into an interior of a rotating ball mill drum, and a water conduit on an exterior of the rotating drum and configured for external water delivery so as to deliver water on the drum exterior. A control system may also be provided for control of the cooling system. A method is also disclosed.

The present invention provides oxide particles having a compositional formula of Pb(Zr.sub.xTi.sub.1-x)O.sub.3, wherein x is 0.46?x?0.6; wherein a size of the particle is from 0.5 to 10 ?m; a porosity of a surface of the particle is 20% or less; and a shape of the particle is any one of a cube, a rectangular parallelepiped, or a truncated octahedron.

A cooling system for a ball mill used for production of a lead oxide is disclosed. The system has an internal nozzle configured to introduce water into an interior of a rotating ball mill drum, and a water conduit on an exterior of the rotating drum and configured for external water delivery so as to deliver water on the drum exterior. A control system may also be provided for control of the cooling system. A method is also disclosed.

A cooling system for a ball mill used for production of a lead oxide is disclosed. The system has an internal nozzle configured to introduce water into an interior of a rotating ball mill drum, and a water conduit on an exterior of the rotating drum and configured for external water delivery so as to deliver water on the drum exterior. A control system may also be provided for control of the cooling system. A method is also disclosed.

A process of treating a solid material containing lead and elemental sulphur, by feeding the solid material to a furnace containing a bath of molten slag under conditions such that elemental sulphur burns in the furnace to form sulphur dioxide and lead in the solid material is oxidized and reports to the slag, then removing a gas stream containing sulphur dioxide from the furnace, and finally removing a lead-containing slag from the furnace.

A process of treating a solid material containing lead and elemental sulphur, by feeding the solid material to a furnace containing a bath of molten slag under conditions such that elemental sulphur burns in the furnace to form sulphur dioxide and lead in the solid material is oxidized and reports to the slag, then removing a gas stream containing sulphur dioxide from the furnace, and finally removing a lead-containing slag from the furnace.

A composition is provided comprising one or more of alpha lead oxide, beta lead oxide, metallic lead. Pb.sub.2O.sub.3 and Pb.sub.3O.sub.4, the composition comprising particles comprising sub-particles, the sub-particles having a mean greatest dimension of from 10 to 300 nm. Methods of making such a composition are also described.

A composition is provided comprising one or more of alpha lead oxide, beta lead oxide, metallic lead. Pb.sub.2O.sub.3 and Pb.sub.3O.sub.4, the composition comprising particles comprising sub-particles, the sub-particles having a mean greatest dimension of from 10 to 300 nm. Methods of making such a composition are also described.