The shift in the Mn content of zinc phosphate crystal films on cold rolled and galvannealed steels and the changes in anti-alkaline properties were investigated at varying concentrations of Mn²⁺ ion in zinc phosphate solutions. At Mn²⁺ ion concentrations from 0 to 2500ppm, the changes in the Mn content of the zinc phosphate crystal films formed were confirmed to be in accordance with the Mn²⁺ ion concentration, with Mn content reaching 6wt.% of Hopeite crystal film on galvannealed steel and 8wt.% of Phosphophyllite crystal film on cold rolled steel.
It has previously been clarified that the Mn²⁺ in the solution acts to modify the chemical structure of zinc phosphate crystal films, and that the modified structures were Zn_3-xMn_x(PO₄₎₂⋅4H₂O for Hopeite and Zn₂(Fe_1-xMn_x)(PO₄₎₂⋅4H₂O for Phosphophyllite. As it was predicted that the anti-alkaline properties of these films would change accordingly, the loss in weight of zinc phosphate crystal films through the action of NaOH solutions adjusted to pH 10.5, 12.0 and 13.0 was discussed. At all values of pH, the weight loss of Hopeite crystal film exceeded that of Phosphophyllite, but the absolute values of weight loss decreased in accordance with Mn²⁺ ion concentration, i.e., with the Mn content in the zinc phosphate crystal films. The decrease in weight loss, i.e., the improvement in anti-alkaline properties was remarkable in the high alkaline region around pH 13.0.

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Because of the highly corrosion resistant properties of hopeite crystals doped with manganese Zn_3-xMn_x(PO₄)₂·4H₂O, EXAFS was applied to analyse the structure. Oxygen atom was found to exist at 1.62Å from manganese atom. However, since φ(K) of a Fourier transform contains a certain phase shift deviation, an inverse Fourier transform and curve fitting were carried out to determine the real bond distance, 2.15Å. There was a difference of approximately 0.5Å between the Mn-O distances obtained by the EXAFS Fourier transform and inverse Fourier transform, and this discrepancy was found to be due to the phase shift deviation. The coordination number for manganese atoms obtained from the 1st peak was 6.8. It was found that the bond distance of 2.15Å corresponds to the Mn-O bond due to the octahedral structure of MnO₂(H₂O)₄ in the hopeite crystals.
Inverse Fourier transform and curve fitting of the 2nd to 4th peaks indicated that all the peaks belonged to the Mn-P bond. The coordination number of phosphorus to manganese for the 2nd peak was 1.0. Therefore, the 2nd peak provided information about the closest phosphorus to manganese in the MnO₂(H₂O)₄ groups.

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Laser Raman spectra were investigated for hopeite crystal films formed on galvannealed steel. Four clear peaks due to PO₄^3- for the crystalline state of hopeite were found at 800-1300cm^-1. Orthophosphate (PO₄^3-), which is a regular tetrahedron, has four basic vibration modes-ν₁, ν₂, ν₃ and ν₄-, of which, ν₁ and ν₃ are observed at 800-1300cm^-1. Here, the main peak corresponds to ν₁ and the other peaks correspond to ν₃ untied and split. A reference sample of 85%-H₃PO₄ showed two peaks in the same region, the main peak corresponding to ν₁ and the sub-peak corresponding to ν₃ degenerated. It was found that a basic vibration mode of ν₃ appears at 1150cm^-1.
Raman spectra were observed for hopeite dissolved in HCI solution. Three peaks were found in the region, but the spectral pattern was quite different from that of crystalline hopeite, and was similar to that of H₃PO₄ aq. soln.. The peak intensity ratio of I₁₀₇₅/I₈₉₀ differed between liquid-state hopeite and H₃PO₄ aq. soln., but the band frequencies of the three peaks were consistent with each other. It was confirmed that the three peaks correspond to the P(OH)₃ and PO stretching vibrations of [H₃PO₄] and the PO₂ stretching vibration of [H₂PO₄^-] formed by the dissociation of H₃PO₄. The PO₂ stretching vibration observed at 1075cm^-1 depends on the dissociation state of H₃PO₄.

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合金化溶融亜鉛めっき鋼板上に形成されるhopeite皮膜と,冷延鋼板上に形成されるphosphophy1-lite皮膜について,皮膜構成金属の成分組成を変化させたときの赤外吸収スペクトルとレーザーラマン分光スペクトの違いに関し考察した。hopeite皮膜の赤外吸収スペクトルにおいては,基本構成分子であるリン酸イオンPO₄^3-の振動モード(ν₁+ν₃)およびν₄が,おのおの900～1200cm^-1と640cm^-1の位置に観測された。そしてマンガン成分を含んだhopeite皮膜ではン3のピークが明瞭に分裂し,マンガン成分を含まないhopeite皮膜のピークよりも低波数側にシフトすることが確認された。一方,レーザーラマン分光においては,hapeite皮膜およびphosphophyllite皮膜のいずれも800～1300cm^-1の範囲に4本のピークをもつラマンスペクトルを確認した。4本のラマンピークはPO₄^3-四面体構造のν₁とν₃に相当するものであるが,固体結晶中ではPO₄^3-の対称性がくずれることにより三重に縮重したν₃が解け,3本に分裂してンユとあわせて4本のピークを形成したものと考えられた。この考えは,リン酸85%原液のラマンスペクトルを測定したことで裏付けられ,ν₃の本来のピークは1150cm^-1であることが判明し,縮重が解けるとこのピークが3ν本に分裂する事実をつかんだ。phosphophyllite皮膜のラマンバンドはhopeite皮膜のそれより低波数側に位置するものであるが,hopeite皮膜中のニヅケルやマンガン成分を増加させるにしたがい,hopeite皮膜のラマンバンドはphosphophyllite皮膜のそれに近づく傾向を示した。これは亜鉛以外の金属成分であるニッケルやマンガンが,hopeite皮膜の亜鉛を一部置換配位し,Zn_3-xMe_x(PO₄)₂・4H₂O(Me:Niand/orMn)の構造をとり,phosphophy11ite皮膜に類似した構造に改質されるためと考えられた。すなわち,リン酸塩皮膜の金属成分は化学的改質効果をもたらすもので,皮膜結晶のモルホロジー改質や耐アルカリ性の機能向上などを発現する重要な因子であり,それに基づく組成制御や皮膜の界面制御は工業技術上および学術上意義あることが確認された。

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The zinc phosphate film that formed on zinc surfaces is known as Hopeite [Zn₃(PO₄)₂⋅4H₂O], and it is known that when crystallized from zinc phosphate solution containning Mn²⁺, the crystal is modified by picking up Mn.
Since ordinary Hopeite dose not possess unpaired electron structure, it is inactive for electron spin resonance, but it was expected that Hopeite crystal containning Mn would become active for ESR because of the action of Mn as the transition metal.
State analysis was therefore performed on zinc phosphate crystal using data on ESR spectrum, and it was found that ordinary Hopeite crystal powder did not respond to ESR, while the modified Hopeite powder did respond showing a broad spectrum. When the modified Hopeite crystal powder was dispersed and suspended in pure water to decrease the Mn component density, the ESR spectrum of the sample gave the distinct six spectra, verifying the existence of Mn component in the modified Hopeite crystal, the chemical form of which was identified as Mn²⁺.
By comparing the spectrum to that of other samples, the chemical structure of Mn in the modified Hopeite was thought to be Zn_3-XMn_X(PO₄)₂⋅4H₂O, i.e., insoluble zinc phosphate crystal.

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Hopeite and Phosphophyllite as zinc phosphate crystals were formed on galvannealed steel (GA) with alloy phase of FeZn₇ and cold rolled steel (CR). The distribution of crystal components were analysed by Auger electron spectroscopy for the surface region and depth profile.
No Mn or Ni was detected on the Hopeite crystal surface and it was therefore concluded that the crystal surface was made up of Zn₃(PO₄₎₂⋅4H₂O. Mn was, however detected on the Phosphophyllite crystal surface. These results correlated with those from X-ray photoelectron spectroscopy described in a previous paper.
In the depth profile analysis, Ar⁺sputtering was applied between 0-64.5min, and the intensity ratios were calculated for O/P, Zn/P, Fe/P, Mn/P and Ni/P from the Auger spectra and were plotted. For both Hopeite and Phosphophyllite crystal, the O/P ratio was constant in the bulk of the crystal layer, indicating that the structure of-PO₄ was maintained uniformely. The ratios of Mn/P and Ni/P were also constant in the bulk of crystal layer.
The ratios for Zn/P and Fe/P of the crystal on GA steel and for Fe/P of the crystal on CR steel, however, showed a radical increase in accordance with the sputtering time. It was thought that this phenomenon was in response to the steel itself through the porosity of zinc phosphate crystal.

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The urinary creatinine and creatine were measured in 40 cases of progressive muscular dystrophy (Duchenne: 34 cases and Limb girdle: 6 cases).
The increased excretion of creatine and the decreased excretion of creatinine were observed in the patients with progressive muscular dystrophy.
The excretion of cratinine and creatine in LG group were almost similar.
Duchenne group showed remarkable excretion of creatine and striking daily variations. These tendency were also found with severe patients.

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Zn₃(PO₄) 2.4 H₂O . ZI1_3-xMnx( P O₄) ₂. 4H ₂O で示されるhopeite結晶の構造状態を知る目的で,XANESスペクトル,EXAFSのFaurier変換,ならびにEXAFSの逆Fourier変換とカーブフィッティング法を適用し解析した。hopeite結晶中の亜鉛およびマンガン原子に対するXANESスペクトルから局所構造の変化を確認し,結晶中のマンガン成分はMn(II)の状態で存在していることを裏付けた。両hopeite結晶中のZn-K吸収端に相当するEXAFSのFourzer変換から.Zn-Oの結合距離を0.145nm付近に得たが,逆Fourier変換とカーブフィッティング法によって位相シフトを補正したところ,実際の結合距離は0.195nm近辺であることを明らかにした。そしてこの結合距離は,hopeite結晶の単位構造である[ZnO₄]の四面体構造内の,Zn-Oに相当するものであることがわかった。一方,改質hopeite結晶中のマンガン原子について同様な解析を試みた。Mn-Oの見かけ上の結合距離は0.162nmと得られたが,位相シフトの補正をしたところ,実際の結合距離は0.215nmであった。マンガン原子の配位数Nは6.8を示し,これはマンガン原子がbopeite結晶の単位構造である[ZnO₂(H₂O)₄]の八面体構造内の亜鉛原子を,[MnO₂(H₂O)₄]のように置換して配位することを示唆した。本研究によって,これまで未解明であったhopeite結晶の改質構造を詳細に解析し決定することが可能となった。

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合金化溶融亜鉛めっき鋼板上に形成される Hopeite 皮膜と, 冷延鋼板上に形成される Phosphophyl-Iite 皮膜について,皮膜構成金属の成分組成を変化させたときのレーザーラマン分光スペクトルにおよぼす影響に関し考察した。
いずれの皮膜においても, 800～1300cm^-1 の範囲にて4本のピークをもつラマンスペクトルを確認したが, このスペクトルは皮膜構成体であるリン酸イオンPO₄^3- の振動スペクトルを意味するものである。Phosphophyllite皮膜のラマンバンドは, Hopeite 皮膜のそれより低波数側に位置するものであるが, Hopeite 皮膜中のニッケルやマンガン成分を増加させるにしたがい, Hopeite 皮膜のラマンバンドは Phosphophyllite 皮膜のそれに近づく傾向を示した。これは亜鉛以外の金属成分であるニッケルやマンガンが, Hopeite 皮膜の亜鉛を一部置換配位し, Zn₃-xMex(PO₄)₂・4H₂0(Me:Ni or Mn) の構造をとり, Phosphophyllite に類似した構造に改質されるためと考えられた。4本のラマンピークは四面体構造のν1 とν3 に相当するものであるが, 結晶中ではPO₄^3- の対称性がくずれることにより三重に縮重したν3 が解け, 3本に分裂してν1 とあわせて4本のピークを形成したものと考えられた。

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Zn₃(PO₄)₂・4H₂OおよびZn₃-xMnx(PO₄)₂・4H₂Oで示されるHopeite結晶の溝造状態について,EXAFSのカーブフィッティング法を適用し解析した。Zn-K吸収端に相当するEXAFSのFourier変換からZn-Oの結合距離は,前者で1.46Å,後者で1.44Å の値を得たが,この場合は実際の結合距離との間にEXAFSの位相シフトの分だけずれる。したがって逆Fourier変換を実施し,カープフゆむイッティング法によって補正した。その結果,前者のZn-Oは1.94Å,後者のそれは1.96Aの値を得,結晶学的データとの一致をみた。また,結晶中の亜鉛は[ZnO₄]の四面体構造と[ZnO₂(H₂0)₄]の八面体溝造とに含まれるものの,本結果かち獣八面体構造の亜鉛については確認されず,四面体構造の再鍋が観測されていることが明らかになった。
Fourier変換で現われた2nd～4thピークについてカ一ブフィッティング法を適用すると,いずれもZn-Pの位置関係を最もよく説明できる結果を得た。特に2ndピークは麗鉛原子に最も近接しているリン原子の情報を与えた。

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The influence of the concentration of Mn²⁺ in zinc phosphate solution on the formation of zinc phosphate crystals on cold rolled steel and electrogalvanized steel was studied. Mn content in Phosphophyllite crystal increased with the increase of Mn²⁺ concentration in the solution, while Fe content in the crystal decreased and Zn content did not vary. In the case of β-Hopeite crystal, the increase of Mn content caused the decrease of Zn content.
X-ray diffraction data showed that the increase of Mn content and the decrease of Fe content in Phosphophyllite crystal had no influence on the P ratio. For both Phosphophyllite and β-Hopeite crystal species, the increse of Mn content contributed to the decline of main peak intensity, and this fact supported the hypothesis that the amorphous component of zinc phosphate film was formed partially. The peak pattern of (312) & (112) of Phosphophyllite crystal varied from two peak to one peak according to the increase of the Mn content in the crystal. In the case of β-Hopeite, 2 θ of (311, 241) was declined. Therefore, it was thought that for both crystals, the structure strain of crystals was caused by the action of Mn content.

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自動車と環境およびエネルギー問題が議論される中，リサイクルや材料規制に大きな動きがみられる．これまで重宝され使用されてきた材料が規制を受け，代替材料への転換が行われつつある．一方，エネルギー領域では資源の有効活用のみならず，地球温暖化の抑止に貢献するシステムが強く求められている．電気自動車やハイブリッド電気自動車用二次電池，および燃料電池システムは，この命題に対する大きな期待を担っている．昨今の研究成果を，テクノロジーとサイエンスの視点から追ってみた．

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