摘要:
A process for producing a partially hydrolyzed polyacrylamide which has a high molecular weight and high water solubility and can be suitably used as a flocculant for water treatment and a size for paper manufacture comprising polymerizing an aqueous solution of an acrylamide monomer in the presence of an alkali metal hydroxide such as sodium hydroxide and boric acid, whereby a partial hydrolysis of the polymer formed is also conducted substantially simultaneously with the polymerization. In an additional embodiment, a maturing of the polyacrylamide produced can be conducted by continuing to heat the polymer solution to increase the hydrolysis percentage.
摘要:
A communication satellite facility and a satellite communication system adapted to respond flexibly to development and change of communication technologies occurring on the ground even after satellites have been launched. The system includes a first satellite having an antenna function, a second satellite having a modem function and a third satellite having a server function all of which are launched into one and same slot of geosynchronous orbit and connected one to another by wideband intersatellite communication. A ground station connected to a ground network communicates with the first satellite.
摘要:
A heat pump system adapted to use a non-azeotropic refrigerant mixture preferably containing a high boiling temperature refrigerant as a primary component thereof is given an improved heat transfer efficiency and its pressure loss is minimized by arranging a refrigerant extracting means for removing the refrigerant stagnating in the system in an unfavorable state, in a vapor state in a condenser or in liquid state in an evaporator and returning the removed refrigerant into a refrigerant circulating passage of the system; and by constructing an evaporator of a flooded type at least at a portion adjacent to a refrigerant outlet portion of the evaporator.
摘要:
A process for preparing a cationic polymer which comprises polymerizing a monomer mixture containing acrylamide and a cationic alkenyl monomer represented by the general formula: ##STR1## wherein R.sup.1 represents H or CH.sub.3 ; R.sup.2 and R.sup.3 represent independently CH.sub.3 or C.sub.2 H.sub.5 ; R.sup.4 represents H, CH.sub.3, C.sub.2 H.sub.5 or a benzyl group; A represents --OC.sub.n H.sub.2n -- (wherein n=2 or 3), ##STR2## or --NC.sub.n H.sub.2n -- (wherein n=2 or 3); and X.sup.- represents Cl.sup.-, Br.sup.-, I.sup.-, CH.sub.3 SO.sub.4.sup.-, C.sub.2 H.sub.5 SO.sub.4.sup.-, 1/2SO.sub.4.sup.-- or CH.sub.3 COO.sup.-, in the form of a sheet in an aqueous medium, characterized in that the composition ratio of acrylamide/cationic alkenyl monomer is within the range of 95/5 to 5/95, and the polymerization is carried out in the presence of a phosphite. The polymers obtained according to this process are free from insolubles produced under the influence of oxygen.
摘要翻译:一种制备阳离子聚合物的方法,其包括聚合含有丙烯酰胺和由以下通式表示的阳离子烯基单体的单体混合物:其中R 1表示H或CH 3; R2和R3独立地表示CH3或C2H5; R4代表H,CH3,C2H5或苄基; A表示-OC n H 2n - (其中n = 2或3),或者-NC n H 2n - (其中n = 2或3); 和X-表示在水性介质中的片状形式的Cl-,Br-,I-,CH 3 SO 4 - ,C 2 H 5 SO 4 - ,1 / 2SO 4 - 或CH 3 COO-,其特征在于丙烯酰胺/阳离子烯基 单体在95/5〜5/95的范围内,聚合在亚磷酸盐存在下进行。 根据该方法获得的聚合物不含在氧气的影响下产生的不溶物。
摘要:
A process is described for producing acrylamide from acrylonitrile using an immobilized microorganism containing gel, which comprises immobilizing a microorganism having nitrilasic activity with a cationic acrylamide-based polymer gel and bringing acrylonitrile into contact with the immobilized microorganism gel in an aqueous medium containing substantially no salt.
摘要:
A structure having a movable dome-type roof including a plurality of independently movable shell sections which nest one beneath the other. A frame superstructure is arched over the dome to support the upper ends of the shell sections. The lower edges of the shell sections are mounted on self-powered carriages and are independently shiftable about a circular base of the structure. By selectively shifting individual shell sections, the dome may be contracted or expanded as desired. The superstructure may be mounted on a circular track or on a pair of linear tracks to expedite the opening and closing of the dome.
摘要:
A process for producing a substantially nonionic water-soluble acrylamide polymer produced without the occurence of hydrolysis of the acrylamide polymer by heating when the reaction system undergoes an unavoidable heat aging such as due to heat of polymerization comprising polymerizing a comparatively high concentration aqueous solution of acrylamide in the presence of a specific water-soluble nitrogen compound.