Abstract: A shade enhancing agent comprises an aqueous resin emulsion composition obtained by polymerizing a monomer in the presence of a cationic surfactant or a cationic protective colloid, polymerizing a monomer and adding a cationic protective colloid or polymerizing a monomer in the presence of a cationic or nonionic emulsifying dispersant so as to have a cationic group in the molecule, a dry film of said composition having a glass transition point (Tg) in the range between 20.degree. C. and 110.degree. C. and a refractive index of 1.50 or less, said emulsion composition having a zeta potential in the range between +5 and +80 mV at an ion strength of 10.sup.-3 and a pH value of 7.

Abstract: An apparatus for tracking an overhead line includes a carriage, an arm provided relatively movable on the carriage, a hook assembly provided at both end portions of the arm and for slinging the arm over the overhead line, a vertical/rotational motion shaft provided vertically movable and rotatably on the carriage, a wheel supporting arm provided on the top end portion of the vertical/rotational motion shaft swingably, a pair of wheels provided at both ends of the wheel supporting arm with an extension line of the vertical/rotational motion shaft being between the wheels, and a clamp member for clamping the wheels on the overhead line.

Abstract: An annular tank for storing nuclear reaction material in an annular space formed among seamless upper and lower annular dies disposed elevationally in a predetermined space and inner and outer sheaths extended on the inner and outer peripheral surfaces of the upper and lower dies. The tank avoids thermal strain and deformation by forming the upper and lower dies in a seamless manner to thus enhance the heat dissipating effect together with high working accuracy and strength. The method of fabricating the annular tank is simple by omitting the use of jigs for welding the segments with less loss and high production yield.