Abstract: A microfluid driving device is provided. The microfluid driving device of this invention comprises microfluid driving platform prepared in a chip, which platform comprises at least two miniature Venturi pumps, at least one microchannel and optionally micro mixers or micro reactors in said microchannel; an external pneumatic flow supply and control module that provides selectively different air flows; and an interface device connecting said microfluid driving platform and said external pneumatic flow supply and control module. The air flows supplied by said the pneumatic flow supply and control module are supplied under selected flow rates and frequencies to said at least two Venturi pumps through said interface device, such that the microfluid inside said microchannel may be driven forward or backward or halt and the transportation, mixing and reaction of the microfluid may be accomplished.

Abstract: A microfluid driving device is provided. The microfluid driving device of this invention comprises microfluid driving platform prepared in a chip, which platform comprises at least two miniature Venturi pumps, at least one microchannel and optionally micro mixers or micro reactors in said microchannel; an external pneumatic flow supply and control module that provides selectively different air flows; and an interface device connecting said microfluid driving platform and said external pneumatic flow supply and control module. The air flows supplied by said the pneumatic flow supply and control module are supplied under selected flow rates and frequencies to said at least two Venturi pumps through said interface device, such that the microfluid inside said microchannel may be driven forward or backward or halt and the transportation, mixing and reaction of the microfluid may be accomplished.

Abstract: A method of preparing a hearth roll with a coating, including: plating a metal on a ceramic powder by using electroless plating; mixing the metal-plated ceramic powder and a metal powder to form a cement powder; and thermally spraying the cement powder onto a hearth roll. Another method is: plating a metal on a ceramic powder by using electroless plating; mixing the metal-plated ceramic powder, a metal powder, and a binder to form a slurry, and subjecting the slurry to granulating and sintering to obtain a sintered powder; and thermally spraying the sintered powder onto a hearth roll.

Abstract: An electric arc ion plating apparatus to coat a metal material on an object includes: (a) an vacuum chamber; (b) an electric arc bombardment chamber in the vacuum chamber, comprising an anode, a cathode target, and an arc triggering electrode to generate metal particles when a voltage is applied on the anode and the cathode, and on the arc triggering electrode; and (c) a magnetic coil having a longitudinal axis. The magnetic coil emanates from the electric arc bombardment chamber and encloses at least a part of the electric bombardment chamber. The magnetic coil contains a constant-diameter section enclosing and immediately emanating from the electric arc bombardment chamber to guide the metal particles away from the cathode and toward the object, and a varying-diameter section away from the electric arc bombardment chamber to provide optimum distribution of the metal particles before they reach the object surface.