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A new monoclinic phase of cerium orthovanadate, CeVO4(H), was found during the course of oxidation of pseudo-perovskite CeVO3 below 400°C. It has been confirmed to crystallize in the huttonite-type structure (C2h5−P21⁄n), that of LaVO4. The lattice parameters were determined to be:a0=6.98A, b0=7.22A, c0=6.76A, β=105°02′, V=328A3 and Z=4.This phase was metastable, and exothermally transformed into a known stable CeVO4 (tetragonal zircon-type, D4h19−I41⁄amd) above 400°C, releasing a small amount of oxygen. From magnetic, chemical and thermogravimetric analyses, the valences of cerium ion and vanadium ion in CeVO4-(H) seem to be tripositive and pentapositive respectively, but V4+ ion is mixed in zircon-type CeVO4; CeVO4(Z).

The reaction products from CeO2 and WOs were studied by quenching method and TG-DTA in air, oxygen and argon(Pe, =10 g atm) atmospheres at 650. v1400eC. Two new binary oxides, 2Ce20segWOs and Ce2Q3e2WOs, were found in addition to well--known Ce20se3 WO3. Their X-ray powder fraction pattems, chemical and mag etic properties, a d melting points and transition points were studied. The mp were 1026 10oC for 2Ce203.9 WO8, 1070 10. C for Ce203.3WO8, and 1395 10. C for Ce203, 2WO8. Ce203, 3WO8 and Ce303.2WO3 had the reversible tra sition point at 1005 10. C and 1105 10. C, respectively, Different products were obtained accerding to atmospheres and temperatures, even if same reactants were used, That is, Ce20s e 2 WOs was not stable and decomposed to Ce20se3WOs and CeO2 in air and oxygen, or in argon below 7900C, and Ce203.3WO3 was also unstable and decomposed to 2 Ce20s e g WO3 and CeO2 in air below 830 C, or in oxygen below 8900C. These results show that the preparation and decompositison of these compounds can be represented by the following equilibrium reactions, 4CeO2 9WOs=2Ce20s.9WOs +O2 (1)4CeOa +2(2 Ce20s.9 WOs)=6(Ce20s.3 WOs) + 02 (2)4CeO2 + 4(Ce20s e 3 WO3)=6(Ce20s, 2 WOs) + 02 (3)The phase relation for these equations in the equilibrium oxgen pressures was determined. The stable region o f each compound was shown in Po2-T diagram.

Ordered perovskites, Ba2(LnMo)O6, Sr2(LnMo)O6 and Ba2(LnW)O6, were newly synthesized. The crystallographic, electrical and magnetic properties for these compounds were investigated. The magnetic moments of Mo5+ and W5+ were determined. Magnetic properties indicated that the interaction between Ln3+(4fn) and Mo5+ (4d1) or W5+(5d1) was fairly weak in these compounds.

Ordered perovskites,(LaSr) (Mn2+W5+)O6 and (LaSr) (Mg2+W5+)O6, were newly prepared. The lattice constants,the electrical conductivities and the magnetic moments were studied. The results indicate that 3d5 electrons in Mn2+ are almost localized and that the interaction between Mn2+ and W5+ is fairly weak in this compound.

三二酸化セリウム (Ce2O3) の材料物性は, 従来ほとんど検討されていなかった. Ce2O3は二酸化セリウム (CeO2) を水素中1400℃以上で還元して得られる. このようにして得た焼結体および粉末を用いて測定を行ない, 以下の結果を得た.(1) Ce2O3は極めて酸化しやすく, 空気中では室温でも酸化の進行が認められ, 加熱した場合は約60℃以上で急激に酸化しCeO2になった. また通常の真空中, アルゴン中, 水素中でも数100℃から1000℃の温度では, いくらか酸化して中間相 (CeO2-x) を生成した. アルカリには不溶, 酸にはゆっくり溶け, 水と反応して水和物をつくることが観察された.(2) Ce2O3の小片を水素気流中, タングステン炉で融点を測定し, 2210±10℃の値を得た. Ce2O3は水素中で融点まで安定に存在したが, 中間相は不安定であった.(3) 熱膨脹の測定から, 線膨脹係数として, Ce2Oに対しては室温で12.0×10-6deg-1, 1350℃で14.8×10-6deg-1が, CeO2に対しては室温で10.0×10-6deg-1, 1100℃で13.5×10-6deg-1が得られた.(4) 電気伝導度の対数logσと温度Tとの関係は, 約950℃にクニックを持つ直線で表わされる. σ300°K=7.7×10-7Ω-1cm-1, σ1673°K=8.0×10-2Ω-1cm-1で活性化エネルギーは高温域で0.95eV, 低温域で0.40eVで, 低温域では, Ce4+の混入による一種のホッピング型電導が現われたものとみなされる.(5) 77°Kから300°Kの間で, Ce2O3の磁化 (M) と磁場 (H) の関係および, 1/xとTの関係はいずれも直線的で常磁性的挙動を示した. θp=-90°K, μeff=2.44 B. M. は理論値と良く一致した.

Amid the increasing popularity of task-based language teaching, task motivation is considered one of the keys to success, but motivational influence among learners has not been sufficiently addressed in the literature. The purpose of this study is to investigate the process of motivation contagion in language learning pair work. Specifically, it tests the hypothesis that motivation contagion in pairs occurs either by observing the motivational orientation of the partner (i.e., priming), or as a result of the perceived expectations of the learning task (i.e., expectancy formation). A total of 140 Japanese university students worked in pairs on a picture description task. The analysis of the post-task questionnaires indicated that motivation contagion occurred both by priming and expectancy formation, but the impact of the latter was more significant. It was also found that highly motivated learners were strongly affected by expectancies about the quality of task involvement and interpersonal relations, while less motivated learners were influenced more by their partners’ motivation levels. Through the learners’ retrospective accounts, we also found that mutually supportive attitudes and behaviors play an essential role in boosting motivation contagion. The findings provide pedagogical implications for designing dyadic activities that can help learners motivate each other.

Preparation and lattice distortion of perovskite-type compounds A2+R4+O3 were studied. All of them belong to the same lattice symmetry of orthorhombic Pbnm,that is,they have monoclinic perovskite cells. The magnitude of the monoclinic distortion increases mainly along the diagonal axis of the b-plane of the perovskite cell with the decrease of “tolerance factor”.

For frequent complications of cardiac involvement, it is important to recognize exactly myotonic dystrophy from a cardiovascular standpoint. Electrophysiological and histological studies were performed in three patients. Analysis of the site of the conduction disturbances was revealed by His bundle electrography proximal to the His bundle in one patient and distal in two other patients. The histological examination for biopsied myocardium by light and electron microscopy disclosed replacement of large areas by fat and also showed varying degrees of cellular damage. The most striking abnormality of the heart muscles was found in the mitochondria in which a peculiar and granular substance bulged into the outer space. Both the conduction system and the myocardium were involved in our cases. The value of His bundle recordings and endomyocardial biopsy in evaluating cardiac abnormality in the disease were discussed.