Abstract: According to one embodiment, a semiconductor storage device includes a plurality of electrode films on a substrate, spaced from one another in a first direction. A charge storage film is provided on a side face the electrode films via a first insulating film. A semiconductor film is provided on a side face of the charge storage film via a second insulating film. The charge storage film includes a plurality of insulator regions contacting the first insulating film, a plurality of semiconductor or conductor regions provided between the insulator regions and another insulator region.

Abstract: An injection control device includes: an arithmetic unit that obtains a valve-closing time for stopping injection of fuel from a fuel injection valve based on a degree of variation in a time change of a voltage generated when the fuel injection valve is driven based on a required injection amount; an injection amount change unit that increases or decreases the required injection amount; and a learning unit that repeats injection control of the fuel to learn the valve-closing time obtained by the arithmetic unit.

Abstract: An injection control device includes: an arithmetic unit that obtains a valve-closing time for stopping injection of fuel from a fuel injection valve based on a degree of variation in a time change of a voltage generated when the fuel injection valve is driven based on a required injection amount; an injection amount change unit that increases or decreases the required injection amount; and a learning unit that repeats injection control of the fuel to learn the valve-closing time obtained by the arithmetic unit.

Abstract: An oil country tubular good for expansion according to the invention is expanded in a well. The oil country tubular good for expansion has a composition containing, in percentage by mass, 0.05% to 0.08% C, at most 0.50% Si, 0.80% to 1.30% Mn, at most 0.030% P, at most 0.020% S, 0.08% to 0.50% Cr, at most 0.01% N, 0.005% to 0.06% Al, at most 0.05% Ti, at most 0.50% Cu, and at most 0.50% Ni, and the balance consisting of Fe and impurities, and a structure having a ferrite ratio of at least 80%. The oil country tubular good for expansion has a yield strength in the range from 276 MPa to 379 MPa and a uniform elongation of at least 16%. Therefore, the oil country tubular good according to the invention has a high pipe expansion characteristic.

Abstract: The martensitic stainless steel according to the invention includes, in percent by mass, 0.010% to 0.030% C, 0.30% to 0.60% Mn, at most 0.040% P, at most 0.0100% S, 10.00% to 15.00% Cr, 2.50% to 8.00% Ni, 1.00% to 5.00% Mo, 0.050% to 0.250% Ti, at most 0.25% V, at most 0.07% N, and at least one of at most 0.50% Si and at most 0.10% Al, the balance consists of Fe and impurities, and the martensitic stainless steel satisfies Expression (1) and has a yield stress in the range from 758 MPa to 862 MPa. In this way, the martensitic stainless steel has a yield stress of 110 ksi grade (a yield stress in the range from 758 MPa to 862 MPa) and the value produced by subtracting the yield stress from the tensile stress is not less than 20.7 MPa. 6.0?Ti/C?10.

Abstract: An oil country tubular good for expansion according to the invention is expanded in a well. The oil country tubular good for expansion has a composition containing, in percentage by mass, 0.05% to 0.08% C, at most 0.50% Si, 0.80% to 1.30% Mn, at most 0.030% P, at most 0.020% S, 0.08% to 0.50% Cr, at most 0.01% N, 0.005% to 0.06% Al, at most 0.05% Ti, at most 0.50% Cu, and at most 0.50% Ni, and the balance consisting of Fe and impurities, and a structure having a ferrite ratio of at least 80%. The oil country tubular good for expansion has a yield strength in the range from 276 MPa to 379 MPa and a uniform elongation of at least 16%. Therefore, the oil country tubular good according to the invention has a high pipe expansion characteristic.

Abstract: A super duplex stainless steel with low susceptibility to weld cracks and high weldability, as well as the resistance to stress corrosion cracking and toughness of the weld zones. The steel is therefore suitable for a wide range of applications including heat exchangers exposed to sea water, brine-resistant equipment and structures, pipings in chemical plants, line pipes, and oil well pipes. The steel includes, in weight %, 2.0% or less Si, 2.0% or less Mn, 22.0-24.0% Cr, 4.5-6.5% Ni, 4.0-4.8% Mo, 0.001-0.15% Al, and 0.25-0.35% N, the remains of Fe and inevitable impurities including 0.03% or less C, 0.05% or less P and 0.005% or less S, and a RVS, the index of susceptibility to cracking on welding, 7 or less, and a PREW, the index of pitting resistance, greater than 40.