Abstract: The present invention relates to a method of analyzing a polyamine having a plurality of amino groups in the same molecule or a monoamine having an amino group and a phenolic hydroxyl group in the same molecule on the basis of the measurement result of the intensity of excimer fluorescence emitted as a result of the derivatization of the polyamine or the monoamine with a fluorescence derivatization reagent having a pyrene group. The method is characterized in that the fluorescence derivatization reagent comprises 2-chloro-4-methoxy-6-(4-(pyren-1-yl) butoxy)-1, 3, 5-triazine represented by the formula (2).

Abstract: An automatic sample introduction device includes a needle, a sample loop, a mixer and a suction injection switch mechanism. The mixer is provided between the needle and the sample loop. The suction injection switch mechanism sequentially sucks first and second fluids into the sample loop through the needle and the mixer and injects the first and second fluids held in the sample loop into a predetermined injection port. A chromatograph includes the automatic sample introduction device having the above-mentioned configuration, an analysis column and a detector. The analysis column is connected to the injection port of the automatic sample introduction device, and the detector is connected to the analysis column.

Abstract: The present invention relates to a method of analyzing a polyamine having a plurality of amino groups in the same molecule or a monoamine having an amino group and a phenolic hydroxyl group in the same molecule on the basis of the measurement result of the intensity of excimer fluorescence emitted as a result of the derivatization of the polyamine or the monoamine with a fluorescence derivatization reagent having a pyrene group. The method is characterized in that the fluorescence derivatization reagent comprises 2-chloro-4-methoxy-6-(4-(pyren-1-yl) butoxy)-1, 3, 5-triazine represented by the formula (2).

Abstract: A crude lactide in a solid state or in an at least partially molten state is brought into contact with ethanol to form a slurry mixture, and then a solid form this slurry mixture is separated to yield a purified lactide having a high purity. A crude lactide is recrystallized from a non-denatured or denatured ethanol to obtain a lactide for a food additive. A lactide is applied widely to food additives. A coagulating agent for an animal and/or vegetable protein containing an optically active lactide as a main component, a food foaming agent containing a lactide as a main component, a food preservative containing a lactide as a main component and a pH regulating agent containing a lactide as a main component are provided.

Abstract: A lactic acid based by-product formed in a process of producing a lactic acid based composition is subjected to racemization in the presence or absence of a catalyst to thereby obtain a lactic acid component having substantially optical inactivity. Then, lactide or polylactic acid having optical inactivity can be obtained from the lactic acid component having the optical inactivity. The obtained lactide or polylactic acid is mixed with lactide or polylactic acid having an optical purity in a range of 90 to 100% e.e. at a predetermined ratio to thereby obtain lactide or polylactic acid having a desired optical purity.

Abstract: The method for producing lactide includes the steps of (a) synthesizing lactide using lactic acid as a starting material; (b) discharging in gaseous states lactide synthesized and impurities formed upon synthesis in step (a); (c) liquefying gaseous components in step (b) and solidifying only lactide, to thereby separate the impurities from the thus-obtained solidified lactide; and (d) returning the separated impurities in step (c) back to the synthesis step (a). The apparatus used for the above production includes (a) a reactor for carrying out synthesis of lactide; (b) a means for gasifying synthesized lactide and impurities formed upon synthesis in the reactor (a) and discharging the resulting gaseous components; (c) a means for cooling the gaseous components to liquefy the gaseous components obtained by the means (b) and solidify only lactide; and (d) a pipe for returning to the reactor (a) components which are not solidified by the means (c).

Abstract: An oriented film with improved tensile strength and Young's modulus can be produced by melting and extruding poly-L-lactic acid and/or poly-D-lactic acid to form a film and, after the film is cooled rapidly, by subjecting it to a stretching process at a temperature above the glass transition temperature and below the cold-crystallization temperature. The stretching may be effected by a method of uniaxial stretching with constant width, successive biaxial stretching or simultaneous biaxial stretching. A thermal treatment may be effected after the stretching process. Films thus obtained have tensile strength over 6 kgf/mm.sup.2 in the stretching direction, Young's modulus over 220 kgf/mm.sup.2 in the stretching direction and transparency to visible light over 90%.