Abstract: An induction motor as driving apparatus includes two stators in which two rotor cores each formed in a squirrel cage type are rotatably mounted on a common rotary axis; two stators which respectively surround the two rotors and on which stator windings are respectively wound; and a switching device which supplies power by sequentially switching between one side of either the one stator winding or the other stator winding and both the sides of the two stator windings. Starting characteristics and operation characteristics of an induction motor are improved thereby enlarging applications of the induction motor, enhancing operation efficiency, and reducing power consumption.

Abstract: An induction motor as driving apparatus includes two stators in which two rotor cores each formed in a squirrel cage type are rotatably mounted on a common rotary axis; two stators which respectively surround the two rotors and on which stator windings are respectively wound; and a switching device which supplies power by sequentially switching between one side of either the one stator winding or the other stator winding and both the sides of the two stator windings. Starting characteristics and operation characteristics of an induction motor are improved thereby enlarging applications of the induction motor, enhancing operation efficiency, and reducing power consumption.

Abstract: A polyimide film having a fluorocarbon resin layer wherein a fluorocarbon resin film treated on its surface with electric discharge is superposed or a fluorocarbon resin coating layer is formed on a surface or surfaces of an aromatic polyimide film, said surface(s) of the polyimide film having been treated with electric discharge.

Abstract: A new honeycomb core structure of heat-resistant aromatic polyimide is disclosed. The structure comprises plural aromatic polyimide sheets wherein adjoining two aromatic polyimide sheets are combined to each other with a heat resistant adhesive at adhesive regions arranged between the two sheets at equal intervals and the adhesive regions on one side of any aromatic polyimide sheet are located at positions shifting from positions of adhesive regions arranged on another side of the sheet. The honeycomb structure is formed by extending the combined aromatic polyimide sheets in the direction vertical to the plane of the polyimide sheets.

Abstract: A new honeycomb core structure of heat-resistant aromatic polyimide is disclosed. The structure comprises plural aromatic polyimide sheets having a second-order transition temperature in the range of 250.degree. C. to 400.degree. C. wherein adjoining aromatic polyimide sheets are adhered to each other by welding the two sheets in regions apart from each other at equal intervals and the welding regions on one side of any aromatic polyimide sheet are located at positions shifted from positions of welding regions arranged on another side of the sheet. The honeycomb structure is formed by extending the combined aromatic polyimide sheets in the direction vertical to the plane of the polyimide sheets while heating the sheets at a temperature higher than their second-order transition temperature.

Abstract: A polyimide film having a fluorocarbon resin layer wherein a fluorocarbon resin film treated on its surface with electric discharge is superposed or a fluorocarbon resin coating layer is formed on a surface or surfaces of an aromatic polyimide film, said surface(s) of the polyimide film having been treated with electric discharge.

Abstract: A geranylgeranylacetamide compound having a piperazine ring represented by the following formula (I) ##STR1## wherein R represents a member selected from the class consisting of a hydrogen atom, C.sub.1 -C.sub.5 alkyl groups which are unsubstituted or mono-substituted by a halogen atom, C.sub.2 -C.sub.5 alkenyl groups and C.sub.7 -C.sub.8 aralkyl groups, R.sub.1 represents a C.sub.1 -C.sub.3 alkyl group, and n represents 0, 1 or 2,and a pharmaceutically acceptable acid addition salt thereof. The aforesaid compound can be prepared by reacting geranylgeranylacetic acid or its reactive derivative with a piperazine compound, and thereafter, if desired, transforming the free geranylgeranylacetamide compound thus obtained into its pharmaceutically acceptable acid addition salt. A pharmaceutical composition containing said compound exhibits antiulcerogenic activity, particularly excellent antipeptic ulcerogenic activity, and is useful as an agent for treating ulcers.

Abstract: An aromatic imide polymer laminate material comprising at least one aromatic imide polymer film consisting essentially of at least one aromatic imide polymer which comprises at least 80 molar % of at least one type of recurring unit of the formula (I): ##STR1## wherein R represents a divalent aromatic radical; and at least one metallic foil which is superimposed on and directly bonded to said aromatic imide polymer film, which laminate material is produced by heat-pressing said aromatic imide polymer film superimposed on said metallic foil at 250.degree. to 600.degree. C. under a pressure of 1 to 2,000 kg/cm.sup.2 without applying a bonding agent between the polymer film and the metallic foil.