Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Hideki Hayashida

Yasuyuki Sakaguchi

Taizo Ito

Hiroyuki Takahashi

Kenji Tamura

Teruo Hosokawa

Taizou Itou

Yasuhiro Kosuge

Fumiyasu Ishigaki

Method and apparatus for measuring a water concentration in ammonia, comprising using ammonia having a water concentration of 10 ppm or less as a reference gas, introducing the ammonia at a constant flow rate into a multi-reflection long optical path gas cell, and measuring infrared absorption intensity of water at at least one measurement wave number in the range of from 3,500 to 4,000 cm, from 2,600 to 3,100 cm, or from 1,900 to 2,400 cmat which infrared absorptions of ammonia and water do not overlap. According to the present invention, analysis of water in a low concentration range of 10 ppm or less in ammonia gas and liquefied ammonia can be performed in a simple and convenient manner.

Method for measuring water concentration in ammonia

Ammonia for use in the manufacture of a GaN-type compound semiconductor, filled in a charging containersuch that at least a part of the ammonia is liquid and the liquid phase ammonia has a water concentration determined by a Fourier-transform infrared spectroscopy (FT-IR) of 0.5 vol ppm or less, is introduced in the gaseous state into a reaction chamberhousing therein a substrateand a layer comprising a GaN-type compound started from this ammonia is formed on the substrate

Ammonia for use in manufacture of GaN-type compound semiconductor and method for manufacturing GaN-type compound semiconductor

Ammonia for use in the manufacture of a GaN-type compound semiconductor, filled in a charging container such that at least a part of the ammonia is liquid and the liquid phase ammonia has a water concentration determined by a Fourier-transform infrared spectroscopy (FT-IR) of 0.5 vol ppm or less, is introduced in the gaseous state into a reaction chamber housing therein a substrate , and a layer comprising a GaN-type compound started from this ammonia is formed on the substrate

Disclosed is a recording medium having a surface layer containing a compound having a layer structure on the recording medium, wherein exchangeable anions are present between layers of the compound and at least a part of said exchangeable anions are monovalent anions. The recording medium has excellent ink absorption property, fixing property of coloring matters and clearness, and is capable of forming an image of excellent sharpness and water resistance.

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Tokyo, Japan

Hideki Hayashida