Abstract: According to an embodiment, a circuit in a semiconductor memory device sets threshold voltages of a plurality of memory cells such that two first distributions are formed in a first section on a lowest voltage side in 2N sections. After that, the circuit sets threshold voltages of the plurality of memory cells such that 2(1+M) second distributions are separately formed two by two. The circuit then sets 2N third distributions for the 2N sections.

Abstract: A method and apparatus to continuously harden articles made of visible light-curable resins, including continuously moving the articles to be hardened relative to a multiplicity of sources of visible light which are independently controllable to be able to vary the radiation to which the articles is exposed during its passage while independently controlling the temperature at which this takes place; and apparatus to accomplish this such that a large number of the objects to be irradiated passing through the hardening apparatus have the same exposure history to the visible light and to heating or cooling respectively. As the result, there is substantially no variation in the physical properties of these photo-polymerized products.

Abstract: A method to continuousky harden light-curable resins, by irradiating at least one shaped article made of a light-curable resin by continuously moving the article past a multiplicity of light sources while changing the flux of the irradiated light in multiple steps corresponding to the moving positions of the object and an apparatus to accomplish this method including means to continuously move the article relative to the multiple irradiation sources and means to adjust the flux density in multiple steps corresponding to the moving positions of the article. Specifically, the flux density of the light irradiated on the moving article is changed stepwide depending upon the position and the location of the article and the polymerization speed of the article and the hardening depth can be controlled in relation to its position and time.

Abstract: In lap joint welding of galvanized sheets, the occurence of blowhole and pit is prevented by applying a blowhole.multidot.pit preventing agent comprising a phosphorus compound as an effective ingredient prior to the arc-welding.

Abstract: A covered arc welding electrode includes a steel core wire and a flux which is applied to the outside periphery of said steel core wire. The welding electrode can form a superior crack-resisting weld zone even if fluctuating stresses are continually applied to a base metal while the base metal is welded. The flux includes 40 to 60% metal carbonate, 10 to 25% metal fluoride and 4 to 25 metal oxide by weight. The flux comprises 24 to 32% of the total weight of said electrode. The composition of the welding electrode includes 0.005 to 0.05% carbon, 0.1 to 1.1% silicon, 1.5 to 2.5% manganese, not more than 0.007% sulfur and not more than 0.25% nickel by weight and the manganese/sulfur ratio is more than or equal to 350 to 1. In addition, the welding electrode can include 0.01 to 0.10% rare earth metal by weight. In which case, the Mn content may be 1.0 to 2.5% by weight and the manganese/sulfur ratio may be more than or equal to 270 to 1.

Abstract: An austenitic stainless steel welded metal layer having the given composition containing delta-ferrite phase is previously overlay welded as an intermediate layer prior to overlay welding of a surface layer of stainless steel, nickel alloy or the like on a base metal of carbon steel or low alloy steel. In the said composition, by making the ratio of Creq/Nieq to be more than 1.85, the disbonding is prevented and by making Creq to be less than 26% and the content of delta-ferrite phase to be less than 20%, the deterioration of flexural elongation is prevented. The present invention is applicable to the lining on an inner surface of a chemical reactor vessel, such as a desulfurizing reactor for petroleum-refining to be used under a high-temperature, high-pressure hydrogen environment.

Abstract: A welding process using a laser beam for joining metals such as steel plates along a see-through groove 10 such as a square groove formed by laser welding between opposed edges of the two metals is disclosed, in which a filler wire 9 is supplied to the see-through groove 10 as shown in FIGS. 3a, 3b and 4 to increase the permissible gap of the see-through groove. A spot 11 of laser beam 1 with a power density of 5.times.10.sup.5 w/cm.sup.2 or above is formed in the see-through groove 10 on the same level as the surface of the metals 3. The filler wire 9 is inserted into a point coincident with the spot 11 of the laser beam 1, or the spot 11 of the laser beam 1 is formed on top of the filler wire 9 in the see-through groove 10. As the filler wire 9 is melted by the laser beam, a globule or droplet formed is formed from it and proceeds to and deposited on the opposed edge faces 12 defining the groove 10 to heat the edges 12 to effect welding.

Abstract: A flux composition suitable for electro-slag over-lay welding a stainless steel on a circumferential inner surface of a cylindrical vessel with a strip electrode under controlling a flow of molten slag and metal with an outer electro-magnetic field, which contains 50-60% by weight of CaF.sub.2, 10-20% by weight of SiO.sub.2, 5-25% by weight of CaO and 10-30% by weight of Al.sub.2 O.sub.3 in a ratio of SiO.sub.2 /CaF.sub.2 of at least 0.20 and a ratio of CaO/SiO.sub.2 of at least 0.50.

Abstract: This disclosure relates to MIG welding. In order to obtain an instantaneous short circuit type of metal transfer in the process using only a pure inert gas shield a small amount of rare earth elements is added to the weld wire. The amount of rare earth added is between 0.02%-0.03% by weight of the wire.

Abstract: Surfacing is conducted with horizontal electro-slag welding by using a strip electrode, and by applying a magnetic field, having component perpendicular to a base metal, to a molten metal and slag pool to control the flow of the molten pool.