Abstract: A method of preparing single crystals. The method of preparation involves preparing precursor materials of a particular composition, heating the precursor material to achieve a peritectic mixture of peritectic liquid and crystals, cooling the peritectic mixture to quench directly the mixture on a porous, wettable inert substrate to wick off the peritectic liquid, leaving single crystals on the porous substrate. Alternatively, the peritectic mixture can be cooled to a solid mass and reheated on a porous, inert substrate to melt the matrix of peritectic fluid while leaving the crystals unmelted, allowing the wicking away of the peritectic liquid.

Abstract: A method of manufacturing an organic electronic device having a substrate and a pair of electrodes facing each other, including the steps of forming a polytetrafluoroethylene oriented film on a substrate, and contacting an oligothiophene compound with the polytetrafluoroethylene oriented film to form an organic oriented film on the polytetrafluoroethylene oriented film between the pair of electrodes wherein the long axis of oligothiophene molecules is oriented to the orientation of the polytetrafluoroethylene oriented film and crystallized.

Abstract: This invention relates to a single crystallization process for purification of dimethyl terephtalate (DMT) by film crystallization, including pumping the raw DMT into a film crystallizer and reducing its temperature to form DMT crystalline on the walls of the crystallizing pipes in the crystallizer, and then heating the crystallizing pipes and collecting the melt at 140.degree.-145.degree. C. The product DMT is thus obtained.

Abstract: A method for producing crystals of a diester phosphate monopotassium salt, comprising(a) reacting the diester phosphate of the formula (I) ##STR1## with potassium hydroxide in a solvent selected from the group consisting of isopropyl alcohol, methylene chloride and chloroform and(b) allowing crystals of the diester phosphate monopotassium salt to precipitate out. The EPC-K crystals produced by the production method of the present invention have extremely fine purity and crystal appearance. Accordingly, the present invention is advantageous in that provision of pharmaceutical preparation superior in efficacy, safety and stability has been made possible.

Abstract: The average size of ammonium sulfate crystals is increased by passing undersized ammonium sulfate crystals through a multistage apparatus in which the crystals are contacted with an aqueous ammonium sulfate spray in a first heated chamber to increase the average size of the crystals, the enlarged crystals thereafter passing through a second heated chamber to dry the enlarged crystals.

Abstract: A method of manufacturing a semiconductor device having a step of growing a plurality of electrically connected p-type group III-V compound semiconductor layers by organo-metallic vapor phase epitaxy. In growing the plurality of p-type group III-V compound semiconductor layers, all or some of the p-type layers are grown by using a Mg organo-metallic compound as a p-type impurity and adding an Al organo-metallic compound of a predetermined amount. Doping both the Mg organo-metallic compound and Al organo-metallic compound at the same time considerably shortens the Mg doping delay.

Abstract: A method for vaporizing an organometal compound and supplying the resulting vapor thereof to a crystal growth chamber which comprises the steps of heating an organometal compound to a predetermined temperature to obtain vapor of the compound at a predetermined vapor pressure and supplying, in a constant flow rate, the vapor to the surface of a substrate heated under a reduced pressure: an apparatus for vaporizing an organometal compound and supplying the resulting vapor thereof to a crystal growth chamber 11 comprising a first gas flow path for the vapor of the organometal compound which connects a container 20, in which the organometal compound is charged, to a crystal growth chamber heated under a reduced pressure through a first valve 21, a first massflow controller 22 and a second valve 23 in this order; and a constant temperature oven 24 and 25 for controlling the temperature of the container 20 and the first gas flow path extending from the container 20 to the second valve 23, are herein disclosed.

Abstract: A method for producing an organic crystal is disclosed. One embodiment comprises maintaining a capillary tube containing a fused liquid of an organic crystal material and having a fused liquid reservoir at one end thereof at a temperature not less than the fusion point of the organic crystal material together with the fused liquid reservoir, reducing the temperature of the fused liquid in the fused liquid reservoir to precipitate seed crystals, and then slowly cooling the capillary tube successively from the end toward the other end to allow a single crystal to grow from the seed crystal in the capillary tube. Because of the large quantity of the fused liquid, a seed crystal can be formed and allowed to grow even from a fused liquid of an organic crystal material which hardly crystallizes in the form of a fused liquid.

Abstract: Disclosed is a method for recrystallizing solid materials (e.g. RDX) from systems comprised of a solute, which is the eventual material recrystallized, a liquid which is a suitable solvent for the solute, and a gaseous component which is soluble within the solvent and whose presence therein causes the solvent to approach or attain a supersaturated state, thereby precipitating (recrystallizing) the solute material. By control of process parameters (pressure, temperature, time, and rate, rate of injection of gas, etc.) the operator can influence the properties of the material recrystallized.