Abstract: An unsaturated imide compound represented by formula (1): ##STR1## wherein Q is an alicyclic structure-containing hydrocarbon group having 4-20 carbon atoms; each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.i and R.sub.j represents a hydrogen atom, a halogen atom, a hydrocarbon group having 1-6 carbon atoms or a halogen-containing hydrocarbon group having 1-6 carbon atoms; each of a, b, c, d, e and f represents an integer of 0 to 4 satisfying a+b.ltoreq.4, c+d.ltoreq.4 and e+f.ltoreq.4 and D represents a divalent organic group having 2-24 carbon atoms and an ethylenically unsaturated double bond, a process for producing the unsaturated imide compound of formula (1) and intermediates for producing the unsaturated imide compound of formula (1). The unsaturated imide compound of formula (1) is well soluble in organic solvents and can give cured products excellent in heat resistance, low water absorption and flexibility.

Abstract: A polyimide represented by the general formula (1): ##STR1## wherein Y represents a hydrocarbon group having 4 to 20 carbon atoms or a sulfur atom; each of R.sub.1 to R.sub.4, R.sub.i and R.sub.j represents a halogen atom, a hydrocarbon group having 1 to 6 carbon atoms or a halogen-containing hydrocarbon group having 1 to 6 carbon atoms; each of a, b, c, d, e and f represents an integer of 0 to 4 satisfying a+b.ltoreq.4, c+d.ltoreq.4 and e+f.ltoreq.4; and X represents a tetravalent organic group having 2 or more carbon atoms.

Abstract: An unsaturated imide compound represented by formula (1): ##STR1## wherein Q is an alicyclic structure-containing hydrocarbon group having 4-20 carbon atoms; each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.i and R.sub.j represents a hydrogen atom, a halogen atom, a hydrocarbon group having 1-6 carbon atoms or a halogen-containing hydrocarbon group having 1-6 carbon atoms; each of a, b, c, d, e and f represents an integer of 0 to 4 satisfying a+b.ltoreq.4, c+d.ltoreq.4 and e+f.ltoreq.4 and D represents a divalent organic group having 2-24 carbon atoms and an ethylenically unsaturated double bond, a process for producing the unsaturated imide compound of formula (1) and intermediates for producing the unsaturated imide compound of formula (1). The unsaturated imide compound of formula (1) is well soluble in organic solvents and can give cured products excellent in heat resistance, low water absorption and flexibility.

Abstract: An unsaturated imide compound represented by formula (1): ##STR1## wherein Q is an alicyclic structure-containing hydrocarbon group having 4-20 carbon atoms; each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.i and R.sub.j represents a hydrogen atom, a halogen atom, a hydrocarbon group having 1-6 carbon atoms or a halogen-containing hydrocarbon group having 1-6 carbon atoms; each of a, b, c, d, e and f represents an integer of 0 to 4 satisfying a+b.ltoreq.4, c+d.ltoreq.4 and e+f.ltoreq.4 and D represents a divalent organic group having 2-24 carbon atoms and an ethylenically unsaturated double bond, a process for producing the unsaturated imide compound of formula (1) and intermediates for producing the unsaturated imide compound of formula (1). The unsaturated imide compound of formula (1) is well soluble in organic solvents and can give cured products excellent in heat resistance, low water absorption and flexibility.

Abstract: A compact optical fiber cable distribution apparatus is provided, that does not require a larger installation floor space and is easily adaptable for increasing and changing of a system. The apparatus comprises a plurality of DF modules (3) accommodated in a shelf (2) in a vertical position and parallel to each other, a fiber tray (5) arranged horizontally directly beneath or above the shelf (2), for the preparation for introducing first optical fiber cables (4) coming from a subscriber circuit and second optical fiber cables (4) connected with a switch board into the DF modules (3). A front section (A) of the fiber tray (5) is used as a guiding path for the first optical fiber cables (4), a rear section (C) is used as a guiding path for the second optical fiber cables (4') and a middle section (B) is used for accommodating the first and second optical fiber cables (4, 4') prior to introduction to the DF module (3). The shelf (2) and fiber tray (5) are combined with each other to form a unit.

Abstract: A valve operating system for an internal combustion engine has an engine valve having a valve shaft portion and a valve body portion at an end tip of the valve shaft portion. The engine valve is supported on the body of the engine for opening and closing operations. A double cylindrical piston forms an air pressure chamber, with the air pressure biasing the valve in a valve closing direction. A driving member for driving the engine valve in a valve opening direction is operatively connected to the rear end of the valve shaft portion.

Abstract: The present invention provides an improved epoxy resin composition comprising an epoxy resin and a novel imide compound represented by the formula ##STR1## wherein X represents an --NH.sub.2 group and/or --OH group, Ar.sub.1 and Ar.sub.2 independently represent an aromatic residue, R.sub.1 represents a hydrogen atom or an alkyl group having from 1 to 10 carbon atoms, R.sub.2 represent a hydrogen atom, an alkyl or alkoxy group having from 1 to 20 carbon atoms or hydroxyl group, and each of m and n represents a number of from 0 to 30.

Abstract: A power supply for negative impedance discharge loads such as discharge tubes used in gas laser systems, in which the discharge power is supplied not from the voltage source but from the current source through the current transformer so that stabilized and well balanced discharge currents can be supplied to a plurality of discharge loads.

Abstract: The present invention provides an improved epoxy resin composition comprising an epoxy resin and a novel imide compound represented by the formula ##STR1## wherein X represents an --NH.sub.2 group and/or --OH group, Ar.sub.1 and Ar.sub.2 independently represent an aromatic residue, R.sub.1 represents a hydrogen atom or an alkyl group having from 1 to 10 carbon atoms, R.sub.2 represents a hydrogen atom, an alkyl or alkoxy group having from 1 to 20 carbon atoms or hydroxyl group, and each of m and n represents a number of from 0 to 30.

Abstract: A hydraulic circuit for a valve operation timing control device for an internal combustion engine which has a low-speed cam having a shape suited for low-speed operation of the engine, a high-speed cam having a shape suited for high-speed operation of the engine, the low- and high-speed cams being integrally formed on a camshaft rotatable in synchronism with a crankshaft, a first rocker arm held in slidable contact with the low-speed cam, a second rocker arm held in slidable contact with the high-speed cam. The first and second rocker arms are adjacent to and in slidable contact with each other and pivotably supported on a rocker shaft for relative angular displacement. There is a first oil feed passage for lubricating the low-speed cam and a second oil feed passage for lubricating the high-speed cam.

Abstract: A valve operating mechanism for an internal combustion engine has a low-speed cam for operating the intake or exhaust valves during low-speed operation of the engine and a high-speed cam for operating the intake or exhaust valves during high-speed operation of the engine. A low-speed lubricating oil passage is provided for supplying lubricating oil to the low-speed cam and a separate high-speed lubricating oil passage is provided for supplying lubricating oil to the high-speed cam. A control valve is connected to said low-speed and high-speed lubricating oil passages for selectively supplying maximum oil pressure to the high-speed lubricating oil passage during high-speed operation while restricting the rate of flow of oil during low-speed operation of the engine and supplying maximum oil pressure to the low-speed lubricating oil passage during low-speed operation of the engine while restricting or eliminating the oil supplied thereto during high-speed operation.