Abstract: The invention discloses a valve driving apparatus for use of an engine including an intake valve for opening and closing an intake port, an exhaust valve for opening and closing an exhaust port, and intake and exhaust cam shafts for driving the intake and exhaust valves respectively, at least one of the intake and exhaust valves being adapted to be driven by a cam shaft located on the other side with respect thereto.

Abstract: A head cover arrangement for a double overhead cam type engine, including a head cover for covering two cam shafts provided, in parallel with each other, on a cylinder head and a boundary member for bounding a hollow defined, between the cam shafts, by the head cover and the cylinder head so as to form a chamber for accommodating a plurality of spark plugs and a plurality of high-tension cords connected to the spark plugs, respectively. The boundary member includes an upper member for constituting a top wall of the chamber and a side member for constituting a side wall of the chamber and the side member is formed with a plurality of recesses for securing the high-tension cords, respectively such that the high-tension cords are drawn out of the chamber through the recesses, respectively.

Abstract: An intake system for an internal combustion engine comprises an intake manifold and a surge tank member connected together to form a plurality of long bowed first discrete intake passages each leading to one of the cylinders and a volume chamber disposed on the upstream ends of the first discrete intake passages. The intake manifold is further provided with a plurality of second discrete intake passages each of which branches off from one of the first discrete intake passages to extend on the inner side of the same and is shorter than the first discrete intake passages, and with a communicating passage for interconnecting the second discrete intake passages. A valve is provided in each second discrete intake passage to open and close the second discrete intake passage according to the operating condition of the engine. A part of the wall defining the communicating passage is formed by a plate member sandwiched between the intake manifold and the surge tank member.

Abstract: A cylinder head construction for a combustion engine, which comprises a wall structure defining a cylinder head lower surface adapted to contact a mating surface of a cylinder block, and having an inwardly recessed wall defining a combustion chamber, an exhaust port defining wall open at one end at said inwardly recessed wall and at the opposite end in a cylinder head side wall, and adapted to be selectively opened and closed by two separate exhaust valves, wherein a pair of exhaust ports, one for each exhaust valve, are defined at least adjacent the exhaust valves, respectively, a coolant passage defined between the wall structure and the exhaust port defining wall, and a wall member extending between the exhaust port defining wall and the wall structure for deflecting a coolant in the coolant passage so as to flow into a space between the exhaust ports.

Abstract: p-n-Alkylbenzoic acids having high purity without containing isomers are important as intermediates for liquid crystals. The p-n-alkylbenzoic acid is produced by reacting a p-formylbenzoic acid or its ester with a ketone having the formula ##STR1## wherein R represents a C.sub.1 -C.sub.18 n-alkyl or n-alkenyl group in the presence of a basic catalyst to obtain an unsaturated ketone compound having the formula ##STR2## wherein R is defined above and X represents hydrogen atom or a C.sub.1 -C.sub.

Abstract: 1,4-Dihydroanthraquinones are produced by oxidizing 1,4,4a,9a-tetrahydroanthraquinone or 1,4-dihydroanthrahydroquinone or an inert substituted derivative thereof with molecular oxygen in an aqueous medium at the reaction temperature of lower than 70.degree. C. under the condition of pH of 8.5 to 12.

Abstract: Benzanthrone is produced by reacting a hydroanthraquinone having 1,4-dihydro ring with acrolein or an acrolein precursor in the presence of a dehydration catalyst.

Abstract: Anthrone is produced by an intramolecular condensation of hydroanthraquinone such as tetrahydroanthraquinone or dihydroanthrahydroquinone by heating it in the absence of oxygen with or without an inert solvent.