摘要:
The blank is made from a tube of silica with a layer of other glass coated on its inner surface. The said other glass is doped with P.sub.2 O.sub.5 for example to increase its refractive index. The blank is then reduced in diameter from a tube to a rod by heating a region of the tube while it rotates in a glassmaker's lathe. The heated region is moved back and forth along the length of the tube until it is finally reduced to a rod. One effect of the moving heated zone is to evaporate some of the doping material, and the vapour tends to move along the tube ahead of the heated zone until it is eventually shifted out of the ends of the tube. To minimize this loss the back and the forth movement of the heated zone includes a sudden step forward at the end of each pass before returning in the opposite direction. This has the effect of jumping the heated zone ahead of the escaping doping material which is then pushed back along the bore of the tube for the next pass, with the jump-ahead-and-reverse operation being repeated at each reversing point of the back and forth heated pass to conserve as much of the doping material as possible inside the tube and finally within the resulting glass fibre blank.
摘要:
A process for the chemical catalytic hydrolysis of an .alpha.-aminonitrile or of one of the salts thereof, characterized in that an aqueous solution containing at least one carbonyl derivative is reacted with the said .alpha.-amine nitrile or with one of the salts thereof in the presence of hydroxide ions.
摘要:
A tunable vibration isolator with active tuning elements having a housing, fluid chamber, and at least one tuning port. A piston is resiliently disposed within the housing. A vibration isolation fluid is disposed within the fluid chambers and the tuning ports. The tunable vibration isolator may employ either a solid tuning mass approach or a liquid tuning mass approach. The active vibration elements are preferably solid-state actuators.
摘要:
A variable stiffness support is disclosed. The variable stiffness support has a support housing that is configured to adjust the orientation of an internal elastomer assembly. The support housing includes an adjustment mechanism, and the elastomer assembly includes an outer ring that encircles an elastomeric material, a central bushing embedded in the elastomeric material, and a plurality of shims embedded in the elastomeric material in a parallel planar fashion.
摘要:
Process for extracting organic compounds which are present in water in the form of solutions or suspensions by a liquid carboxylic acid which is immiscible with water. Branched or unbranched linear acids such as n-heptanoic, n-octanoic, or 2-ethylhexanoic acids make it possible to quantitatively extract compounds such as phenols, amines or amino acids from such aqueous solutions, thereby rendering the process useful for the purification of industrial wastewaters.
摘要:
The device for carrying out the continuous process for synthesizing an .alpha.-amino acid incorporates: (a) a vessel (10) for feeding .alpha.-amino-nitrile, or one of its salts; (b) a connecting pipe (12), in which a pump (14) is mounted, connecting the feed vessel (10) to (c) a catalysis column (16) containing a carbonyl-containing polymeric resin (18) which is insoluble in basic aqueous medium; (d) a connecting pipe (20) from the catalysis column (16) to (e) a hydrolysis reactor (22), acting simultaneously as a reservoir for the .alpha.-amino acid salt formed, and equipped with (f) means for feeding hydroxide ions, comprising a feed vessel (24), a pipe (26) and a pump (28); and (g) a pipe (30) for drawing off the .alpha.-amino acid salt formed.