Michihiro Murata

X-ray photoelectron spectroscopic study of perovskite titanates and related compounds: An example of the effect of polarization on chemical shifts

Abstract The differences of the binding energy of the Ti 2P 3 2 electrons obtained by X-ray photoelectron spectroscopy in various perovskite type titanates and related compounds have been studied. The titanium compounds studied were titanium dioxide (anatase and rutile), calcium titanate, strontium titanate, lead titanate and barium titanate. The oxidation number of the titanium ion for all of these compounds is formally 4+. However, the X-ray photoelectron spectra show small shifts in the Ti 2p 3 2 binding energy as the cation is varied. An analysis of data led to the conclusion that this shift is mainly due to differences in polarization energy between these compounds.

Chemical preparation of PLZT powder from aqueous solution

Abstract A new method for preparing homogeneous lanthanum-modified lead zirconate-titanate (PLZT) powder from aqueous salt solution containing hydrogen peroxide by precipitation is described. Inorganic salts such as zirconium oxychloride and titanium tetrachloride instead of organo-metallic salts can be available as raw materials which attain well reactioned and fine-grained PLZT powder processed by decomposing the dried product at 650°C. PLZT ceramics formed by hot-pressing the powder show considerable improvements in the qualities such as optical transparency and homogeneity.

Analyses of PLZT Electrooptic Shutter and Shutter Array

The driving voltage and light transmittance in PLZT transverse electrooptic shutters composed of interdigital electrodes are investigated theoretically, with the electrode width, electrode gap, and wafer thickness being treated by the finite-element method. A new structure consisting of a combination of metal and transparent electrodes is presented, giving improved transmittance and driving voltage. Furthermore, the finite-element method is used to investigate the optimum driving voltage, fluctuation in light intensity, and S/N ratio in a one-dimensional optical shutter array. The combination of metal and transparent electrodes also brings about a low driving voltage, high transmittance and high S/N ratio in the shutter array.

PLZT Electrooptic Shutter

A PLZT electrooptic shutter composed of several regions each having a different electric field shows some excellent properties such as good transmittance spectra and stable operation against fluctuations in driving voltage and ambient temperature.

Fabrication of Transparent PZLT Ceramics by Atmosphere Sintering

Pressure-less fabrication process of lanthanum-modified lead zirconate titanate (PLZT) electrooptic ceramics has been developed. Fine-particle PLZT powders having excellent reaction and homogeneous composition were fabricated by a chemical preparation method using inexpensive starting materials. Optically transparent PLZT ceramics were obtained by sintering this chemically-prepared powder under O2-gas flow and atmosphere PLZT powder.

HELIUM ISOTOPE RATIO MEASUREMENT BY A SINGLE FOCUSING MASS SPECTROMETER WITH LARGE INCIDENT AND EXIT ANGLES

Abstract A single focusing mass spectrometer ( r m = 6 cm, φ m = 130°) with large incident and exit angles (55°) has been developed to measure 3 He/ 4 He ratios. A resolving power of about 600 at 5% of peak height was attained in order to separate 3 He ions from those of H 3 and HD. The sensitivity for 3 He was about 0.3 A (cm 3 STP) −1 by use of a secondary electron multiplier, which was high enough to measure the 3 He/ 4 He ratio of terrestrial gas samples. The mass discrimination factor of the system was calculated using an in-house standard prepared by mixing known amounts of pure 3 He and 4 He. The 3 He/ 4 He ratio of the atmosphere was measured by repeated runs. The value of (1.35 ± 0.05) × 10 −6 agrees well with literature values within experimental error margin. Since the whole measuring system is significantly compact and light enough to load on an automobile, it is applicable to field studies related to earthquake prediction and volcanic eruption.

Direct chelatometric determination of lead and titanium in lead titanate and similar compounds

チタン酸鉛の迅速分析法として,キシレノールオレンジを指示薬とする鉛標準溶液による逆滴定法を検討した.チタン(IV)のマスキングに,フッ化アンモニウム-ホウ酸が有効であることを見いだし,分離操作を必要としない分析法を確立した.すなわち,試料溶液に既知量の0.02M EDTA溶液を加え,pH5.0で過剰EDTAを0.01M 鉛標準溶液で逆滴定して鉛,チタン合量を定量する.別に,フッ化アンモニウム-ホウ酸によりチタン(IV) をマスクし,同様に滴定して鉛を定量する.両定量結果から鉛,チタン量が求められる.本法による定量値の変動係数(C. V. %)は,チタン,鉛に対してそれぞれ0.37, 0.23%である.チタン酸鉛,チタン酸バリウム,チタン酸バリウム鉛固溶体の分析に本法を適用し,好結果を得た.