Abstract: A loudspeaker diaphragm comprising a molded, sintered ceramic body is described. The body is made of ceramic crystalline particles whose maximum size is below 1/5 time a thickness of the body which is in the form of a dome or cone. The dome- or cone-shaped diaphragm may have a flange along an opening side thereof in order to prevent deformation as may occur during firing.

Abstract: There is here disclosed a calcining apparatus for a powdery material comprising a first preheating series composed of a calcining kiln and preheaters at a plurality of stages for heating the powdery material with an exhaust gas from the calcining kiln, a second preheating series composed of other preheaters at a plurality of stages for heating the powdery material with an exhaust gas from a rotary kiln, and a gas carrying pipe for connecting the first and second preheating series in the middle thereof, a flow path for the powdery material being adapted so that the powdery material fed to each series may be led into the rotary kiln via a combining duct disposed in front of the undermost preheaters in both the series and then via the undermost portions of both the series. Further, disclosed is a calcining apparatus for a powdery material in which a sub-calcining kiln and a calcining chamber are disposed on an exhaust gas pipe extending from a rotary kiln.

Abstract: An electronic valve control apparatus for operating a valve device connected to a water supply pipeline for spraying water over the field or land comprising: a solar battery; a secondary battery charged therefrom; an electronic clock; a calendar circuit; a logic circuit which delivers output valve control signals in response to a predetermined schedule; and a valve driving circuit which controls the valve device.

Abstract: A filler for filling in defects or hollow portions of bones to coalesce with the bone tissues is provided which comprises powders of a calcium phosphate compound having the apatite crystalline structure of each crystallite size of 400 .ANG. or larger and of each crystal grain size of 3 .mu.m or smaller, said calcium phosphate compound being represented by the following general formula of Ca.sub.m (PO.sub.4).sub.n OH (1.33.ltoreq.m/n.ltoreq.1.95), and said powders being fluidized or plasticized.

Abstract: A process for making a porous sintered body of calcium phosphate having continuous and fine pores distributed uniformly throughout the porous body is provided which comprises the steps of: preparing a slurry of amorphous calcium phosphate having a molar ratio of calcium to phosphor ranging within 1.59 to 1.80; adding a foaming agent to said slurry; dipping a porous body of an organic material having continuous and fine void channels into said slurry prior to or after foaming said slurry to allow said slurry to adhere on the internal walls of said void channels; heating said porous body of said organic material at a temperature high enough for decomposing said organic material to varnish into smoke and concurrently for thermally converting said amorphous calcium phosphate into hydroxyapatite to form a network of hydroxyapatite; and sintering said network of hydroxyapatite to form said porous sintered body.

Abstract: In digging and hauling soil, rocks, minerals and the like by the use of a dragline the invention provides a novel combination of said dragline, a conveyor means for hauling the materials dug, and a hopper means disposed over and movable along said conveyor means whereby material may be efficiently excavated and transported out of the working area.

Abstract: In digging and hauling soil, rocks, minerals and the like by the use of a dragline the invention provides a novel combination of said dragline, a conveyor for hauling the materials dug, and a hopper disposed over and movable along the conveyor whereby material may be efficiently excavated and transported out of the working area.

Abstract: A novel dragline is provided which is equipped with hopper means and loading means. More specifically, the dragline of the invention comprises a hopper means mounted on the front portion of a revolving frame rotatably mounted on a mobile base, the hopper means receiving rocks and stones, soil and sand, minerals and the like dug and carried by a bucket, a guide means for guiding the bucket to a position over the hopper means so that the excavated material is loaded into the hopper means, and a loading means disposed below the hopper means for receiving and transferring the material into another transport means, at least the downstream end portion of the loading means being pivotable. The dragline of the invention makes it possible to dig rocks and stones, soil and sand, minerals, etc. in an efficient manner on a large scale and to load them into a transport means.

Abstract: A process for preparing dielectric or semiconductive films which have densely packed structures. In a process comprising spreading a powdery ceramic material suspended in a binder and solvent on to a base plate to form a thin layer and subjecting the layer to firing, the improvement being provisionally firing the thin layer to remove the binder and solvent, cooling the resulting thin layer, covering the thin layer with an organic film, compressing the thin layer and the film to densely pack the thin layer and to adhere the thin layer to the film, prior to the firing.