A method for producing an alkyl (3R,5S)-7-[2-cyclopropyl-4-(4-fluorophenyl)quinolin-3-yl]-3,5-dihydroxy-6- -heptenoate of the formula (1) (wherein R is a C.sub.1-4 alkyl group), which is an intermediate for a cholesterol-reducing agent (a HMG-CoA reductase inhibitor), etc. A solution containing a compound of the formula (1) is subjected to liquid chromatography treatment using silica gel as the packing material, to separate its epimers contained therein. ##STR00001##

A method and apparatus is provided for connecting an optical source to a multimode optical fibre in a multimode optical fibre communications system. A single mode fibre length is provided such that optical radiation admitted from an optical source at one end of the single mode fibre length is provided to a multimode optical fibre at the other end of the single mode fibre length. This method and apparatus is used in a duplex patchcord for connecting an optical transceiver to a pair of installed m...

A wave-shaped portion 5b, the profile of which is formed into a wave-shape, is provided on the core plate 5, and tubes are brazed to the core plate 5 under the condition that the tubes are inserted into holes 5c formed in bent portions 5a. Due to the above structure, even when a pitch between the tubes is reduced, it is possible to ensure a sufficiently high mechanical strength of the core plate 5. Accordingly, the occurrence of a big difference in the mechanical strength between the core plate ...

The ground-drilling device comprises an elongated mount (10) comprising a track (11) for guiding a main carriage (25). The drive means for the main carriage (25) consists of a piston-cylinder unit (27) which extends below the track (11) under the main carriage and whose cylinder (28) is supported on the mount (10) via a link (29). The piston rod (30) engages the fore end of the main carriage (25). The piston-cylinder unit (27) does not project or only slightly projects beyond the rearward end of...

A method of preparing graphite fluoride such as (CF).sub.n or (C.sub.2 F).sub.n by heterogeneous contact reaction between a carbon material such as graphite or petroleum coke and fluorine gas at about 200.degree.-550.degree. C. In the gas phase of the reaction system, the total concentration of higher fluorocarbons having more than four carbon atoms formed by side reactions is controlled so as not to become above 3% by volume by, for example, condensation or catalytic decomposition of at least a...

A high-pressure butterfly valve having pressure enhanced sealing which comprises a valve body defined by a pair of interfitting body plates that are retained in assembly by bolts that also secure the valve mechanism into a flow line. The interfitting valve plates also cooperate to define a seal recess within which is received an annular sealing element that provides a peripheral seal about a butterfly disc that is rotatably supported within a flow passage defined by the valve body plates. The an...

A pneumatic tire or the like has a protective chain assembly wrapped therearound. The chain assembly comprises a plurality of rings coupled together by notched and co-planar cylindrical coupling means which also serve as tread sections on the periphery of the tire. Each coupling member attaches two of the rings together to form a tire chain assembly exhibiting multi-directional flexibility. In addition, the integrated chain assembly is reversible and the dimensions thereof may be selectively var...

A hydraulic or air operated drill press. This device is composed primarily of hydraulic or air operated cylinder which provides pressure for a diamond core bit for drilling underwater holes.

A traverse head for a rotary drill rig includes a motor and gearcase supported by and drivably connected to a rotatable shaft disposed on a frame. The shaft includes a pair of spaced apart pinions drivably engaged with a pair of parallel gear racks mounted on an elongated mast whereby the traverse head may be driven along the mast to perform pulldown and hoisting movements on a drill stem. The traverse head includes a motor and gear housing mounted on the frame and connected to the drill stem. T...

The invention relates to a heat exchanger (10) with tubes (80) and a collector box (20). Said collector box (20) has a tube-plate (30) with tube openings (60) and with angled or rounded lateral regions (110,120).