Abstract: Provided are a carbon fiber thermoplastic resin prepreg which is a carbon fiber prepreg obtained by impregnating a PAN-based carbon fiber in which the average fiber fineness of a single fiber is 1.0 dtex to 2.4 dtex with a thermoplastic resin, wherein the thermoplastic resin satisfies 20?(FM/FS)?40 (where FM: flexural modulus (MPa) of a resin sheet comprising only the thermoplastic resin, and FS: flexural strength (MPa) of the resin sheet), a method for manufacturing the same, and a carbon fiber composite material employing the carbon fiber prepreg.

Abstract: For a Periodic Table Group 13 metal nitride semiconductor crystal obtained by epitaxial growth on the main surface of a base substrate that has a nonpolar plane and/or a semipolar plane as its main surface, an object of the present invention is to provide a high-quality semiconductor crystal that has a low absorption coefficient, is favorable for a device, and is controlled dopant concentration in the crystal, and to provide a production method that can produce the semiconductor crystal. A high-quality Periodic Table Group 13 metal nitride semiconductor crystal that has a precisely controlled dopant concentration within the crystal and a low absorption coefficient and that is thus favorable for a device, can be provided by inhibiting oxygen doping caused by impurity oxygen and having the Si concentration higher than the O concentration.

Abstract: The invention provides: a polycondensation catalyst for polyester production, which contains titanium atoms, alkaline earth metal atoms and phosphorus atoms, has high reactivity and excellent long-term storage stability, can be easily produced industrially, and has an advantage in cost; a polyester resin obtained with the catalyst; and a molded article. These are: a polymerization catalyst for polyester production containing titanium atoms, alkaline earth metal atoms and phosphorus atoms and having a specific constitution; a polyester resin obtained with the catalyst; and a molded article.