Abstract: Provided are a method for preparing a polyetherketoneketone and a polyetherketoneketone prepared thereby, wherein, at the time of a polymerization reaction, nitrogen gas is blown into a liquid reaction medium while stirring, thereby quickly removing hydrochloric acid, which is a by-product generated during the reaction, and preventing aggregation of resin particles, thus suppressing the generation of scales.

Abstract: Disclosed are a sample holder for X-ray diffraction analysis and an X-ray diffraction analysis method using the same. The sample holder for X-ray diffraction analysis includes a housing part formed of a side wall and a bottom plate with an open upper portion thereof, the housing part including an inner space partitioned from the side wall and the bottom plate, a cover part configured to cover the upper portion of the housing part and to allow X-rays to pass therethrough, and a support part installed to be movable upwards and downwards in the inner space, the support part including a plate-shaped substrate having a predetermined area, the substrate having a sample placed thereon.

Abstract: There is provided a method for preparing a polyisocyanate composition capable of improving transparency of a product, by mixing a phenol-based stabilizer in an amount of 1 to 1000 ppmw, based on the total weight of aromatic diisocynate, and then, introducing polyhydric alcohol to conduct a polymerization reaction, thereby inhibiting coloration and whitening due to oxygen or moisture during synthesis and purification processes.

Abstract: The present invention relates to a method for preparing an aliphatic isocyanate capable of suppressing the occurrence of side reactions and the production of by-products. The method for preparing an aliphatic isocyanate comprises a step of reacting a salt of an aliphatic amine with phosgene, wherein the reaction step comprises a first reaction step in which phosgene is primarily added and reacted with the salt of an aliphatic amine salt at a temperature of 80 to 100° C., and a second reaction step in which phosgene is secondarily added and reacted with the resultant product of the first reaction step at a temperature of 120 to 160° C., and wherein the amount of the primarily added phosgene is a certain ratio of the total amount of the phosgene.

Abstract: The present invention relates to a method for preparing an aliphatic isocyanate capable of suppressing the occurrence of side reactions and the production of by-products. The method for preparing an aliphatic isocyanate comprises a step of reacting a salt of an aliphatic amine with phosgene, wherein the reaction step comprises a first reaction step in which phosgene is primarily added and reacted with the salt of an aliphatic amine salt at a temperature of 80 to 100° C., and a second reaction step in which phosgene is secondarily added and reacted with the resultant product of the first reaction step at a temperature of 120 to 160° C., and wherein the amount of the primarily added phosgene is a certain ratio of the total amount of the phosgene.

Abstract: Provided are a method for preparing a polyetherketoneketone and a polyetherketoneketone prepared thereby, wherein, at the time of a polymerization reaction, nitrogen gas is blown into a liquid reaction medium while stirring, thereby quickly removing hydrochloric acid, which is a by-product generated during the reaction, and preventing aggregation of resin particles, thus suppressing the generation of scales.

Abstract: The present invention relates to a method for preparing an aliphatic isocyanate capable of suppressing the occurrence of side reactions and the production of by-products. The method for preparing an aliphatic isocyanate comprises a step of reacting a salt of an aliphatic amine with phosgene, wherein the reaction step comprises a first reaction step in which phosgene is primarily added and reacted with the salt of an aliphatic amine salt at a temperature of 80 to 100° C., and a second reaction step in which phosgene is secondarily added and reacted with the resultant product of the first reaction step at a temperature of 120 to 160° C., and wherein the amount of the primarily added phosgene is a certain ratio of the total amount of the phosgene.

Abstract: For fabricating lean-free stacked capacitors, openings are formed through layers of materials including a layer of support material displaced from a bottom of the openings. A respective first electrode is formed for a respective capacitor within each of the openings. The layer of support material is patterned to form support structures around the first electrodes. Masking spacers are formed around exposed top portions of the first electrodes, and exposed portions of the support material are etched away to form the support structures. Such stacked capacitors are applied within a DRAM (dynamic random access memory).

Abstract: For fabricating lean-free stacked capacitors, openings are formed through layers of materials including a layer of support material displaced from a bottom of the openings. A respective first electrode is formed for a respective capacitor within each of the openings. The layer of support material is patterned to form support structures around the first electrodes. Masking spacers are formed around exposed top portions of the first electrodes, and exposed portions of the support material are etched away to form the support structures. Such stacked capacitors are applied within a DRAM (dynamic random access memory).

Abstract: For fabricating lean-free stacked capacitors, openings are formed through layers of materials including a layer of support material displaced from a bottom of the openings. A respective first electrode is formed for a respective capacitor within each of the openings. The layer of support material is patterned to form support structures around the first electrodes. Masking spacers are formed around exposed top portions of the first electrodes, and exposed portions of the support material are etched away to form the support structures. Such stacked capacitors are applied within a DRAM (dynamic random access memory).