西岡 洋

350-nm-thick BiFeO3(BFO) thin films have been deposited by dual ion beam sputtering on SrRuO3-buffered SrTiO3(001) substrates of 0° and 0.5° off-cut along [100] at various Bi2O3-side/Fe2O3-side beam current ratio. The BFO thin film on 0.5° off-cut STO substrate deposited at beam current ratio of 20 mA/30 mA show fully saturated D-E hysteresis loops at room temperature. The remanent polarization (2Pr) was 132 μC/cm2. Stripe domain structure was also observed in IP piezoelectric response image. It is considered that the improvement of leakage of BFO on 0.5° off-cut STO substrate is due to reduction of 109° domain walls. © 2011 IEEE.

Epitaxially a- and b-axis-oriented (Bi 3.25Nd 0.75) Ti 3O 12 (BNT-0.75) films and nanoplates have been fabricated on four Nb:TiO 2(101) substrates with 0-0.79 mass% Nb by high-temperature sputtering. It is shown from piezoresponse scanning force microscopy (PFM) measurements that the effective piezoelectric coefficients (d 33) at room temperature derived from the two linear gradients for the asymmetric displacement-voltage hysteresis loop are 11-13 pm/V. © 2011 IEEE.

Vertical distributions of some heavy metals in bottom sediment of Harima-nada are described. A high accumulation of chromium was found at the point C. This result probably corresponds to the number of leather mills on the Basin of Ibo River. The tendency to decrease of chromium in every point showed that the environmental policy was successful in this area. The vertical distribution of manganese showed its typical tendency. Surface layer of sediment was relatively oxidative. Therefore, manganese accumulates as the deposit of manganese dioxide. In lower layer, manganese will dissolve as manganese ion. As for copper and zinc, relatively high accumulations were found at the point A and B. These accumulations are due to natural resources from Ikuno mine locating headwaters of Ichi River.

A flow injection system is described for the determination of aluminum. This method is based on the formation of a fluorescent complex with 2-(3-thienyl)-3-hydroxy-6-fluorochromone. The maximum wavelength of its excitation and emission spectra are 408 and 460nm, respectively. A 200μl aliquot of sample solution is injected into a carrier (distilled water), which is pumped at 1.1ml min^<-1>. The reagent solution is prepared by mixing the chromone ethanol solution (1×10^<-4>M) and buffer solution (pH 4.9) in the volume ratio of 10:1. The reagent solution is also pumped at 1.1ml min^<-1>. Aluminum ion in the sample solution reacts with chromone in the coil (0.5mm i.d. x 1m) to form a fluorescent complex. A linear relationship was observed between peak heights and aluminum concentrations in the range of 1.4-100ng ml^<-1> A routine sampling rate of 40 determinations per hour can be achieved by the proposed method.

This paper presents the quantitative analysis and influence of CO&lt;sub&gt;2&lt;/sub&gt; dissolved in TMAH for silicon etching. The etching rate on the (100) plane increases at first and then decreases with the increase of CO&lt;sub&gt;2&lt;/sub&gt; concentration. The etching rate on the (110) plane decreases monotonously with the increase of CO&lt;sub&gt;2&lt;/sub&gt; concentration. Although the etching rate on the (110) plane is higher than that on the (100) plane at ordinary conditions, this relationship is reversed at a certain quantity of CO&lt;sub&gt;2&lt;/sub&gt; dissolution. The etch-stop appears at higher concentration of CO&lt;sub&gt;2&lt;/sub&gt; dissolution. It was confirmed that changes of the silicon etching characteristics are caused by concentration of carbonate anions. The CO&lt;sub&gt;2&lt;/sub&gt; dissolution has influence on the (100) plane and no influence on the (110) plane.

本法ではキャリアー, 試薬溶液 (2%アルフッソン溶液) の流速を共に1.42ml/minに設定し, 測定波長を640nm, 試料注入量を200μl, 反応コイル長を3.5mとした条件で, 1時間当り40試料の分析が可能であった. また, フッ化物イオン濃度5mg/lの試料を10回繰り返し注入して得られた変動係数は0.40%であった, 標準添加法により海水中のフッ化物イオンの定量を行い,良好な結果を得た.