Abstract: A transplanting machine or equipment for taking seedlings of vegetables or the like from a seedling table 13 and planting them in a field. The machine has a transmission mechanism including a transmission case, a first rotary case (32) driven by a driving device and a second rotary case (33) which rotates reversely to the first rotary case. The rotary cases are linearly extended in a vertical direction while they overlap in contracted form in a longitudinal or horizontal direction. A seedling transplanting tool is carried by the second rotary case. The seedlings are easily removed from a seedling table located at a high position on the machine and transplanted without extending the length of the transplanting equipment in the longitudinal or horizontal direction.

Abstract: A catalyst useful in the practice of a process, in which (meth)acrylamide is prepared through the hydration reaction between (meth)acrylonitrile and water in a suspended liquid-phase bed of a Raney copper catalyst, has been obtained by leaching a Raney copper alloy in the presence of the Raney copper catalyst which has been deteriorated. The above useful catalyst has higher performances, compared with a catalyst obtained by conventionally leaching the Raney copper alloy alone, has satisfactory handling properties in settling and filtering, and can significantly reduced the amount of catalyst to be discarded.

Abstract: Acrylamide crystals are prepared from an aqueous solution of acrylamide by causing the aqueous solution and a coolant to flow inside each electrolytically-polished cooling tube of a double-walled or shell-and-tube heat exchanger and outside the cooling tube, respectively, instead of relying upon vacuum crystallization.

Abstract: In a process for producing acrylamide by hydrating acrylonitrile in the presence of a copper-based catalyst, the reaction is carried out in the presence of 30 to 10,000 ppm of acetone in the reaction solution. According to this process, the activity of the copper-based catalyst is maintained and the economic advantage of acrylamide production is enhanced.

Abstract: An aqueous solution of acrylamide obtained by catalytic hydration of acrylonitrile in the presence of a copper-based catalyst is purified by the steps, in sequence, of (a) removal of the unreacted acrylonitrile, (b) removal of copper, (c) treatment under basic conditions, (d) cation exchanging treatment and (e) weakly basic anion exchanging treatment. The acrylamide obtained by this process has good storage stability. An acrylamide polymer produced from this monomer is useful as a flocculant having a reduced content of the unreacted monomer, a high molecular weight and excellent solubility in water.

Abstract: An improved process for converting acrylonitrile to the corresponding amide by hydrating said nitrile in the presence of a metallic copper catalyst and aluminum nitrate as promoter for said catalyst.

Abstract: An improved process is disclosed for the purification of an aqueous solution of acrylamide. It comprises bringing a crude aqueous solution of acrylamide into contact with oxygen or an oxygen-containing gas and thereafter subjecting the solution to a dual treatment with a strongly acidic cation exchange resin followed by a weakly basic anion exchange resin. If necessary, the aqueous solution of acrylamide is treated, while maintaining its oxygen content at least at 4ppm and then subjected to the treatment with the ion exchange resins.

Abstract: A method for economically concentrating an acrylamide aqueous solution by catalytic hydration without substantial deterioration in the product. According to the method, an acrylamide aqueous solution obtained from catalytic hydration, is concentrated by distillation while maintaining the solution in good contact with at least 0.1 mole. or more of air per mole of water distilled from the acrylamide aqueous solution.

Abstract: A process for continuously manufacturing acrylamide by hydrating acrylonitrile in the presence of a free metallic copper catalyst, characterized in that a reactor is employed, which is internally partitioned into a catalyst slurry circulating section and a catalyst precipitating section, and that raw materials and supplementary catalyst are supplied continuously into the reactor and at the same time the clear reaction liquid and a portion of the catalyst are continuously taken out of the reactor so that the properties of the catalyst are maintained constant.

Abstract: An improved process for preparing acrylamide or methacrylamide which process comprises the step of reacting acrylonitrile or methacrylonitrile with water in the presence of a catalyst system consisting of a metallic copper containing catalyst and a copper salt promoter, said copper salt being copper sulfate, copper nitrate, copper halide, or a copper salt of a lower fatty acid.

Abstract: There is disclosed a method for handling acrylamide aqueous solutions with safety wherein acrylamide aqueous solutions obtained through catalytic hydration reaction of acrylonitrile are handled using utensils made from phenol resin, polyethylene, polypropylene, polyvinylchloride resin or fluorine-containing resin or glass or using such utensils that are provided with linings formed by these materials.

Abstract: A method of purifying an aqueous solution of acrylamide, which has been formed by reacting acrylonitrile with water in the presences of the metallic copper catalyst, and which contains cuprous ions, comprising treating said aqueous solution in a reaction zone which is substantially free of an oxygen containing gas or liquid.