Abstract: A driver circuit 2 generates a pulse current on the basis of an electrical pulse outputted from a timing generating portion 1. A light source 3 emits a light pulse according to the pulse current. The light pulse outputted from the light source 3 goes to a delay optical fiber 9 through an optical waveguide directional coupler 4, and then goes to a measuring optical fiber 10. A delay circuit 11 delays a digital operation of a digital operating portion 7, by a time required for said light pulse to go back and forth in the delay optical fiber 9.

Abstract: An optical pulse generator comprises a signal source, an excitation light source, a first optical fibre, a first lens, a diffraction grating, a second lens, a second optical fibre and an optical switch. Herein, signal beams produced form the signal source are transmitted through the first optical fibre, first lens, diffraction grating and second lens in turn, so that a signal beam having a desired wavelength is selectively outputted. This signal beam is converged onto and is incident to a terminal portion of the second optical fibre which is excited by an excitation beam produced from the excitation light source. Under an operation of the optical switch, the terminal portion of the second optical fibre is vibrated, resulting that an optical path to be formed between the first optical fibre and the second optical fibre is periodically opened or closed. Thus, an optical pulse of which amplitude is controlled and of which pulse width is also desirably controlled is outputted form the second optical fibre.

Abstract: A high-power light pulse generating apparatus in which an optical fiber doped with a rare earth element is used in an optical system for facilitating control and and adjustment of the apparatus. The light output power and the pulse width thereof can be varied simply by changing the characteristics and the length of the optical fiber. In the high-power light pulse generating apparatus, an output of an optical pumping light source (2) is inputted to an optical coupler (3) which constitutes an optical loop in cooperation with the optical fiber (1) doped with a rare earth element, an optical decoupler(4), an optical switch (5A), an isolator (7) and an input port of the optical coupler (3). By turning on the optical switch (5A), a high-power light pulse can be generated through the optical loop and extracted from an output port of the optical decoupler (4).

Abstract: A high power light pulse generator apparatus using an optical loop formed through a rare earth-containing optical fiber. In the optical loop, selected one of a plurality of optical fiber cords having different lengths is inserted to change the overall length of the optical loop and thus a light pulse of different pulse width is withdrawn from loop.

Abstract: A plated article comprising a molded article having a metal coating deposited thereon, the molded article being formed of a resin composition consisting essentially of 10 to 90% by weight of a polybutylene terephthalate resin and 90 to 10% by weight of an ABS resin containing 5 to 70% by weight of a rubber component composed mainly of polybutadiene, which plated article has excellent thermal resistance, mechanical strength and solvent resistance.

Abstract: A highly crystalline polyethylene terephthalate resin composition comprising (A) 100 parts by weight of a polyethylene terephthalate copolymer comprising ethylene terephthalate units as the main recurring units, which is formed by copolymerizing a glycol component containing 1 to 20% by weight of a polyalkylene glycol having an average molecular weight of 500 to 20,000 and 1.2 to 15% by weight of diethylene glycol with a carboxylic acid component composed mainly of terephthalic acid, (B) 5 to 200 parts by weight of a fibrous reinforcer, (C) 0.5 to 130 parts by weight of a nucleating agent, and (D) 0.1 to 60 parts by weight of a crystallization-promoting agent. The resin composition optionally contains 2 to 100 parts by weight of an inorganic compound, 2 to 100 parts by weight of an impact strength improver, 2 to 40 parts by weight of a flame retardant, or 1 to 20 parts by weight of a flame retardant assistant.

Abstract: Apparatus for stirring hydrogel particles of a water-soluble polymer made as a tank defined by a drum within which is housed an inner drum. Water-soluble polymers are introduced through a top opening in the tank into an annular space defined by the inner wall surfaces of the tank and the outer wall surfaces of the inner drum. The water-soluble polymer contents in the annular space are stirred by vanes mounted on a corresponding vertically disposed driven arms. The vanes have leading surfaces advanced in different circular paths within the annular space. One of the vane stirring arms and vane thereon is disposed to travel along a circular path in the vicinity of the inner surfaces of the tank and the other stirring arm vane and corresponding vane are advanced along a circular path in the vicinity of the outer wall surfaces of the inner drum.

Abstract: Polyacrylamide in the form of aquagel is partially hydrolyzed in such a manner that small pieces of the aquagel are mixed with an alkali agent in a specified quantity and maintained at a temperature of 50.degree. to 95.degree. C. until the hydrolysis reaches substantial completion. The quantity of the alkali agent is that corresponding to 1/1.1 to 1/3 of the hydrolysis percentage desired of the final partially hydrolyzed polyacrylamide. The partially hydrolyzed polyacrylamide thus produced is characterized by uniform hydrolysis evidenced by its improved solubility in water and a pH around 7 of its aqueous solution. The term "aquagel" is herein used interchangeably with a term "hydrogel".

Abstract: Acrylamide polymers having remarkably high molecular weights can be obtained by polymerizing acrylamide or a monomer mixture comprising a preponderant quantity of acrylamide in an aqueous medium with the use of a specific redox initiator and a specific azo compound initiator. The polymerization initiator used in this porcess comprises a combination of a persulfate, formaldehyde sodium sufoxylate and 2,2'-azobis-2-amidinopropane.

Abstract: When an alkaline substance is added to and mixed with aggregates of the mutually adhering blobs of a hydrogel of an acrylamide polymer, (1) a mixing tank in which the portion to be contacted with the hydrogel of an acrylamide polymer is made of a chromium-plated material is used, and (2) to said hydrogel aggregates is added at least one compound represented by the general formulae: ##STR1## wherein R.sub.1 is a residue obtained by removing two OH groups from a saturated dihydric alcohol having 2 to 4 carbon atoms, and R.sub.2 is a residue obtained by removing three OH groups from a saturated trihydric alcohol having 3 to 6 carbon atoms, and having an average molecular weight of 500 to 5,000, whereby the hydrolysis of the acrylamide polymer can be achieved at a high efficiency while preventing the mutual adhesion of the hydrogel aggregates and also reducing the adhesion of the aggregates to the interior surface of the mixing tank to such an extent that there is substantially no problem of adhesion.

Abstract: In the production of a dried acrylamide polymer by polymerizing, in an aqueous medium, acrylamide alone or a monomer mixture comprising 50 mole % or more of acrylamide and at least one monomer copolymerizable therewith with a radical initiator, and then drying the resulting hydrous acrylamide polymer, the allowing of at least one of the following compounds [I], [II] and [III] to be present in the drying step or a step prior thereto enables the dried acrylamide polymer having a high molecular weight and a good dissolvability in water to be obtained:[I] a non-polymerizable compound having in its molecule at least one group represented by the formula, ##STR1## wherein R.sub.1 is H or an alkyl group having up to 4 carbon atoms, [II] a compound represented by the formula, R.sub.2 --S--C.sub.n H.sub.2n X wherein n is an integer of 1 to 8, R.sub.2 is an alkyl group, an aryl group or --C.sub.n H.sub.2n X, in which X is --OH, --COOH (or its salt), --CN or --CONH.sub.

Abstract: In the production of a dried acrylamide polymer by polymerizing, in an aqueous medium, acrylamide alone or a monomer mixture comprising 50 mole % or more of acrylamide and at least one monomer copolymerizable therewith with a radical initiator, and then drying the resulting hydrous acrylamide polymer, the allowing of 2-mercaptobenzimidazole to be present in the drying step or a step prior thereto enables the dried acrylamide polymer having a high molecular weight and a good dissolvability in water to be obtained.

Abstract: A thermoplastic graft polymer composition excellent in weather resistance, impact resistance and appearance is obtained by seed-polymerizing 50 to 95 parts by weight of a mixture (b) of 60% by weight or more of at least one acrylic ester, 39.9% by weight or less of at least one monomer copolymerizable therewith and 0.1 to 10% by weight of at least one crosslinking monomer having at least two non-conjugated C .dbd. C bonds in the presence of 5 to 50 parts by weight (solids) of a latex (particle size: 0.04 to 0.24 .mu.) of a crosslinked rigid resin (a) having a glass transition temperature of at least 50.degree. C., a decomposition temperature of at least 240.degree. C.

Abstract: This invention relates to a flame-resistant resin composition improved in arc resistance, comprising polytetramethylene terephthalate, a flame-retardant halogen compound, and sodium antimonate or a sodium antimonate-antimony trioxide mixture containing 40% by weight or more of sodium antimonate, and optionally talc, the amount of the halogen compound being 3 to 50 parts by weight per 100 parts by weight of polytetramethylene terephthalate, the weight ratio of the halogen compound to the total antimony compound being 0.25 to 6, and the amount of talc being 0 to 60% by weight based on the weight of the composition. This composition may also contain a reinforcing filler.

Abstract: A flame-resistant resin composition consisting essentially of 100 parts by weight of polytetramethylene terephthalate, 3 to 40 parts by weight of a flame retardant represented by the general formula, ##SPC1##Wherein n + m is a number of 0 to 10; X is a bromine or chlorine atom; and i, j, k and l are individually an integer of 1 to 4, and antimony trioxide, the weight ratio of said flame retardant to said antimony trioxide being in the range of from 0.25 to 6. This composition is excellent in mechanical properties, thermal properties and moldability, and causes no spread of fire to other materials even when dripped at the time of combustion.