電気抵抗の大きい非水溶液に対しても安定した定電流を流すことのできる定電流回路を試作し,定電流クーロメトリーによる・法を検討した.終点の決定は定電圧電流法により行なった.定電流回路,電解セルの構造,電解液の組成,電解セル内の除湿および防湿などの検討を行なった.
電解液にホルムアミドを加えると滴定の終点が明確,安定になり,かつまた,電気伝導度がよいので,電解液の発熱を防止することができた.電解液にホルムアミドを加え,電解セル内の除湿および防湿をじゅうぶんに行なったのち実験した結果は,メタノール2ml中の水分4mgを相対誤差3%程度で定量することができた.

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Pyrolysis reaction rates of carbonization gas have been determined with 13 coal blends in recent coke-making process. It was confirmed that the rate increases with the increase of the volatile mater. It was suggested that the rates are closely related to the oxygen content of coals and tar yields. That is, the rate increases with increasing tar yields and decreases with increasing oxygen content in coals.

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以上の実験でわかったことを要約すれば次のようになる.
ナイロンを冷却器付滴定フラスコ中でクレゾールと共に加熱,溶解し,これをK. F.滴定する方法によれば,
1. 配合剤を含まないナイロン中の水分を±0.05%の絶対誤差で定量し得る.
2. 定量に要する時間は,5試料を同時に処理した場合,約3時間である.
3. 老化防止剤,可塑剤等を含むナイロンにおいては,これら配合剤と,K. F.試薬との反応の有無等を検討してからでなくては,本方法は適用出来ない.

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固体，液体および大気中に含まれる微量水分を検出・定量できる分析法の確立は，工業製品や食品の品質管理，構造物の劣化部分の漏水検出，環境モニタリングなどの人間生活や環境保全の面で非常に重要である。代表的な水分検出法であるカール・フィッシャー水分測定法は，高感度であるが，試料中や試料表面の水分を可視化することは難しい。一方，蛍光性水センサーを開発することができれば，迅速，高感度かつ目視による可視化（蛍光発光による画像化）も可能な水分検出・定量化蛍光分析法の確立を図れるものと期待できる。そこで，本稿では，試料中および試料表面の微量水分を蛍光性色素の光誘起電子移動（Photo-induced electron transfer：PET）に基づいて検出・定量化かつ可視化できるPET型蛍光性水センサーのさまざまな有機溶媒中での水分に対する蛍光センシング特性と微量水分検出のメカニズムについて紹介する。

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In this work, bipolar membrane (BPM) was prepared and membrane characteristics were studied.
A novel bipolar membrane was prepared by forming polypyrrole from a pyrrole monomer in the presence of Fe³⁺ at the interface between commercial cation and anion exchange membranes.
In an electrodialytic cell composed of four compartments with BPM fixed in the central portion, the current-voltage curve was measured under constant current supply. The current-voltage relation indicated an Ohmic change against the positive current, while the relation abruptly increased the current against the negative current. The increased current seems to be attributable to the proton and hydroxyl ions that were produced inside the bipolar membrane. According to the equation introduced by Mafe et al., these phenomena were interpreted as being due to the increased rate constant of water dissociation in the bipolar membrane.
On the other hand, water splitting was also noticed because of pH changes in the KCl solution when dc current was supplied through a pair of Pt electrodes from the anion exchange layer to the cation exchange layer of BPM. When a reverse current (positive current) was applied to the same system, water splitting did not take place. Concentrations of protons or hydroxyl ions calculated from pH values changed linearly in relation to time and each flux was obtained from the slope of the relations. Furthermore, current efficiency was estimated as the ratio of flux to added current. It was indicated that the current efficiency is closely related to donnan salts in bipolar membrane.

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Using the lightning impulse voltages of ±1.2/50 μs and ±1.2/1000 μs with ±140 kV_peak in maximum, the behaviors of creeping streamers progressed in a narrow gap between two solid dielectric plates immersed in palm fatty acid ester (PFAE) oil were investigated. The discharge shapes and the streamer lengths were observed using a still camera equipped with a night viewer and the progression steps of the streamer were observed using a high-speed image converter camera. The effects of two interfaces between solid dielectrics, the back side electrode (BSE) and the wave tail of impulse voltages were examined on the growth of positive and negative streamers, the flashover voltage and the streamer velocity. The streamer length is extended by the presence of the BSE and a long wave tail of impulse voltage. This results in the reduction of the flashover voltage. It is worthy of notice that the negative streamer progressed in a narrow gap grows longer than the positive streamer under identical applied voltage. This polarity effect on the streamer length is the inverse from that in an oil/pressboard interface without a narrow gap. The streamers in both polarities also slow down its velocity because of a narrow gap with two solid interfaces. These results on the creeping discharge have been compared with those in commercial mineral oil.

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The 2004 eruption of Asama volcano, central Japan, was characterized by emergence of small amount of andesite lava in the summit crater, strombolian explosions and a series of vulcanian explosions. There is a good correlation between the degree of differentiation of glass in juvenile ash and repose times between successive explosions. Glass in ash erupted after a long repose time is high in SiO₂ content and crystallinity. In contrast, glass in ash from continuous strombolian explosions is less evolved chemically and is poorer in microlites. The chemical compositions of the evolved glasses in the Qz-Ab-Or diagram suggest that the magma was degassed at lower pressures. This is supported by low H₂O contents of the least vesicular rinds on bread crust bombs. In addition, complexly deformed fragments of white-colored volcanic sediment containing high SiO₂ glass and silica minerals, which probably originated from beneath the volcano, shows substantial heating evidenced by partial melting of the sediment and further modification by strong shearing along the conduit wall during magma ascent. The eruptive sequence can be modeled, as follows; 1) magma emerged continuously in the summit crater, accompanied by strombolian explosions (lava emergence and strombolian stage). 2) Magma became stagnant and crystallized at a shallow level in the conduit (repose period and crystallizing stage). 3) Vulcanian eruption occurred when crystallizing magma was pressurized by addition of new magma and/or gas accumulation sufficient to overcome the strength of a lava plug present below the crater (vulcanian stage). The 2004 eruption was marked by repetitions of this cycle and the conduit probably was choked when magma supply stopped. The deformed nature of volcanic sediment entrapped as xenoliths suggests significant shearing between viscous magma and the conduit wall.

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