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Akitoshi Komura

Bio: Akitoshi Komura is an academic researcher. The author has contributed to research in topics: Magnesium & Solubility. The author has an hindex of 4, co-authored 9 publications receiving 40 citations.
Topics: Magnesium, Solubility, Cobalt, Potassium, Ion

Papers
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Journal ArticleDOI
TL;DR: The reactions of tungstophosphate with cobalt ion and the properties of heteropolytung states containing cobalt have been investigated in this article. But the results of the analysis were limited to the presence of cobalt in the heteropolyanion.
Abstract: The reactions of tungstophosphate with cobalt ion and the properties of heteropolytungstates containing cobalt have been investigated. Unsaturated heteropolyanion PW11O397− produced by the partial degradation of the parent 12-tungstophosphoric acid reacts with cobalt ion to give 11-tungstocobaltophosphate PCoW11O40H25−. Discussion is given on the presence of cobalt in the heteropolyanion and on the above reaction. Both 12-tungstocobaltate-(II) and -(III) are very resistant to acid, but 11-tungstocobaltophosphates lose cobalt ion in strongly acidic solutions to give the parent 12-acid. Some aspects of the spectra of the heteropolytungstates, in which cobalt(II) and cobalt(III), respectively, are present in the specific site, are discussed.

18 citations

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TL;DR: In this paper, the infrared and electronic spectra of the complex ion Mo2O4(dtc)2, MoO3Cl4(bpy)2 (bpy=2,2′-bipyridyl) and MoOCl3.
Abstract: Reactions of the complex ion [Mo2O4(C2O4)2(H2O)2]2− (I) have been investigated. On acidification with perchloric acid and hydrochloric acid, complex (I) gave molybdenum(V) aqua-dimer ion [Mo2O4(H2O)6]2+, which was converted into the monomeric species [MoOCl5]2− in concentrated hydrochloric acid. The initial reaction of complex (I) with mercaptoacetic acid, giving a complex of stoichiometry 1 ligand: 1 Mo, was followed by a slower reaction which probably gave higher complexes. In the reactions with o-aminophenol and 2,2′-bipyridyl, complexes of stoichiometry 1 ligand: 1 Mo and 1 ligand: 2 Mo, respectively, were formed in solutions. The following complexes have been isolated: Mo2O4(dtc)2, Mo2O3(dtc)4 (dtc=diethyldithiocarbamate), MoOCl3. phen (phen=1,10-phenanthroline), and Mo2O3Cl4(bpy)2 (bpy=2,2′-bipyridyl). The infrared and electronic spectra of the complexes and their probable structures are given. The relative ease of replacement of ligands from complex (I) has been discussed.

8 citations

Journal ArticleDOI
TL;DR: For example, this paper reported that 0.1mol% of the users' responses were negative. But they did not specify the reasons for their negative responses. But, they did mention that
Abstract: 溶融塩化リチウム- 塩化カリウム混合塩に対する金属リチウムの溶解度を測定し, 酸素, 窒素が溶解度に及ぼす影響を調べた。450℃で共融塩に対する溶解度はきわめて小さく約0.1mol%であった。従来, 金属の電解製造における電流効率低下の主要な原因は金属の浴中への溶解に起因するものと考えられていたが,この結果によると,電析したリチウムが空気中の水分,酸素,窒素と反応して生成したリチウム化合物が浴中へ溶解することが主要な原因の一つであることが明らかとなった。

6 citations

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TL;DR: MgCl2 系に対するMgの溶解度はアルカリ塩化物の添加によって減少し, その依存性の勾配からMgの絷電力が750℃で測定された。
Abstract: 溶融MgCl2 系に対する金属Mgの溶解度とMg濃淡電池の起電力が750℃で測定された。Mg濃淡電池の起電力はMgの濃度の対数に直線的に依存することがわかった。この依存性の勾配からMgの溶解生成物はMgoまたはMg22+であることが推定された。溶融MgCl2に対するMgの溶解度はアルカリ塩化物の添加によって減少し, その減少割合はアルカリ金属の原子番号の増加とともに増大することが認められた。アルカリ塩化物系ではその原子番号の増加とともにMgCl2との錯形成能が増大するので, Mgの溶解度は溶解塩中のMg2+ 活量に比例すると考えられる。したがって, 溶融塩中におけるMgの溶解種はMgoよりもむしろMg22+イオンであると結論されるであろう。

5 citations

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TL;DR: In this paper, the authors describe the characteristics of the environment in which they live and describe their experiences in the environment of a large number of different environments, such as the following:
Abstract: 塩化マグネシウムの電解における陰極電流効率の低下に対する酸化マグネシウムおよび酸化ホウ素の作用機構について検討した。酸化マグネシウムはマグネシウムの溶解度には影響しないので,その効果は浴中へのマグネシウム粒子の分散を引き起こすためと考えられる。このようなマグネシウム粒子の凝集の妨害は, 溶融塩中に分散した酸化マグネシウムがマグネシウム粒子の表面に吸着することによるものと推定される。また, 酸化ホウ素の添加はマグネシウムの溶解度にほとんど影響がないうえ, これは陰極で電気化学的な還元もうけない。しかし, 酸化ホウ素はマグネシウムと反応してマグネシウムの損失をまねくばかりでなく, 反応の結果マグネシウム粒子の表面に酸化マグネシウムやホウ化マグネシウムなどを生成する。そのため, マグネシウム粒子の分散をも助長することになるので, マグネシウムの電流効率は大きく低下するものと推定される。

1 citations


Cited by
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Journal ArticleDOI
TL;DR: This review aims to rationalise the findings of the many 'optimised' molybdenum blue methods in the literature in terms of the underlying polyoxometallate chemistry and offers suggestions for the further enhancement of this time-honoured analytical reaction.

231 citations

Journal ArticleDOI
01 Nov 1989-Zeolites
TL;DR: In this paper, the authors show that the stabilization of Co(III) in framework positions of calcined, cobalt-substituted aluminophosphate molecular sieves has been demonstrated.

92 citations

Journal ArticleDOI
TL;DR: In this paper, electrolysis with a Mg anode is presented to purify the molten chloride salt (MgCl2/KCl/NaCl 60/20/20 ) for reducing its corrosivity.

67 citations

Journal ArticleDOI
TL;DR: In this article, the first and second-lowest energy CT bands of polyoxoanions are qualitatively discussed from the CT interactions among some octahedral units in the UV bands.

57 citations

Journal ArticleDOI
TL;DR: In this paper, the thermal decomposition of the tetrabutylammonium (TBA) salts was studied by thermal analyses and the decomposition products identified by powder X-ray diffraction, FTIR and NMR spectroscopy.

53 citations