Chemical composition of clinopyroxenes associated with the gehlenite skarn from the Hirata outcrop, Kushiro, Tojo-Cho, Hiroshima Prefecture, Japan

The clinopyroxenes of the hybrid rocks from the Hirata outcrop, Kushiro, Hiroshima Prefecture, Japan are grouped into(1)diopside, (2)aegirine, and (3)zoned pyroxene. The diopside occurs as isolated crystals enclosed in feldspars. The aegirine occurs along with late hydrous minerals in pore spaces. The zoned pyroxenes occur as discrete cryatals with wide rims growing interstitially between feldspar laths and show a continuous composition-al trend from diopside through hedenbergite and aegirine-augite to aegirine or titanian aegirine. The pyroxenes enclosed in feldspars and the cores of the zoned crystals have nearly same chemical composition. The late stage pyroxenes are characterized by extreme enrichment of sodium and sometimes titanium. The titanian aegirines studied hera are characterized by the predominance of the Na(Fe2+, Mg)0.5Ti0.5Si2O6 component over other Ti-bearing pyroxene components. The compositional trend of clinopyroxenes from the Hirata hybrid rocks follows a typical trend of peralkalne rocks. The peralkaline neture of the Hirata samples is a result of compositional change of magma accompanied by the metasomatic skarn formation

Lithium contents in the hot spring waters in western Japan

Sixty-five samples of mineral waters (mainly above 25℃) from western Japan were analyzed for their Li, Na, K, Mg, Ca, Al, Fe, and Cl contents. The determination of Li was carried out by argentimetric titration of LiCI after the removal of other components by the cation exchange chromatography. A significant correlation between Li and Na concentrations is demonstrated in most samples, in which the contamination of sea water is hardly conceivable. This strong correlation of Li and Na can plausibly be explained assuming that these components have dissolved into the ascending mineral waters from the country rocks having fairly uniform Li to Na ratios. In this connection it is noted that western Japan is characteristic of the vast outcrops of granodioritic or granitic rocks

Hands-on Experience Programs in Science, Intended for Pupils from Elementary to Upper Secondary School

本稿は1995年から2004年まで、小・中学生および高校生を対象に実施してきた各種の科学実験体験活動の実践報告である。これらの体験活動は、岡山大学教育学部理科教育講座の教員とそれぞれの研究室に属する学部生・大学院生たちが実践してきたものである。活動の企画、教材開発、活動の運営、子どもたちに対する実験内容の説明から実験指導に至るまで、ほとんどを学生たちの自主性に任せた。教員は学生たちに対する支援に徹することを原則とした。これらの活動を通して得られた成果や、実践活動を行うに当たって、日頃の自然科学の探究活動の大切さについても触れる。This is a report of various educational practices in science from 1995 to 2004, designed for elementary school pupils and lower/upper secondary school students. These out-school activities were carried out by the teachers and their students of graduate and undergraduate courses who belong to the Department of Science Education, Faculty of Education, Okayama University. Almost everything was left up to the initiative and judgment of graduate/undergraduate students, such as planning and organizing the programs, developing do-it-yourself science materials, explaining to pupils what the experiment is like and how to conduct the experiment. As facilitators of the program, we supported activities of graduate/undergraduate students. The benefits of taking an active part in these programs, and the importance of hands-on learning activities in science are shown and emphasized in this paper

The Lectures on the Development of Teaching Plans and Teaching Materials Tried in the Science Education Class in Master's Course, Okayama University

岡山大学大学院教育学研究科の理科教育専攻の講義として、教材開発・授業案開発をテーマとした新しい講義を試みたのでその報告を行う。本講義は、理科教育講座に所属する大学院生、理科教育講座の大学教員、附属学校の理科関係の教諭が三者協働で進めることが特徴である。課題設定、教材開発を含めた実践準備および実践を院生チームを組み遂行させ、さらに経験や専門性の異なる人材と論議を重ねて活動を進めることを通じ、将来、協働で学校現場の課題提案・解決を行うことのできる能力を養うことを目標とした。This is a report of the new type of lectures on the development of teaching plans and teaching materials attempted in the science class in the Master's Course, Okayama University. The lectures were conducted in collaboration of the graduate students and the academic staffs in the science education course, and the science teachers of the attached school of Okayama University. The graduate students were grouped into two teams of five or six people, assigned to decide on themes, prepare and practice the development of teaching plans and teaching materials. They conducted their activities discussing problems with people of different experience and specialty, thus developing the ability to jointly propose and solve problems at schools in future

The crystal structure of scapolite in the Luetzow-Holm Bay region, East Antarctica

The crystal structure of scapolite from the Liitzow-Holm Bay region, East Antarctica with cell formular (Na_Ca_K_Mg_) _ (Al_Si_Fe_) _O_ (Cl_(CO_3) _) _, Me_, was determined in tetragonal, P4_2/n, a=12.122(2); c=7.585(2) A by the single crystal X-ray diffraction method. The structure is the same as that of meionite but with some difference in atomic coordinates and Al percentage in the tetrahedon. The CO_3 groups were mainly disordered on the xy plane and off-centred from the Anion site. The cation site was 8-coordinate rather than 6-coordinate