The University of Tokyo · 환경과학
요시오 타카하시 교수의 연구실은 환경 화학과 재료 과학을 융합한 연구를 중심으로, 특히 토양 및 수질에서 As, Fe, Mn 등의 화학 종의 이동성과 화학적 형태를 XANES 및 순차적 추출 기법을 통해 규명합니다. 또한, 대기 중 먼지의 화학적 변화와 철의 생물 이용 가능성, 나노구조 광학 결정성 유리의 비선형 광학 특성 등 다양한 환경 및 신소재 문제를 다룹니다. 연구는 환경 오염 저감과 첨단 기능 소재 개발의 두 축을 아우릅니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
The behavior of As in paddy fields is of great interest considering high As contents of groundwater in several Asian countries where rice is the main staple. We determined the concentrations of Fe, Mn, and As in soil, soil water, and groundwater samples collected at different depths down to 2 m in an experimental paddy field in Japan during the cycle of flooded and non-flooded periods. In addition, we measured the oxidation states of Fe, Mn, and As in situ in soil samples using X-ray absorption
Abstract. In the North Pacific, transport and deposition of mineral dust from Asia appear to be one of major sources of iron which can regulate growth of phytoplankton in the ocean. In this process, it is essential to identify chemical species of iron contained in Asian dust, because bioavailability of iron in the ocean is strongly influenced by the solubility of iron, which in turn is dependent on iron species in the dust. Here, we report that clay minerals (illite and chlorite) in the dusts ne
Transparent optical nonlinear crystallized glasses with the composition of 25La2O3 25B2O3 50GeO2, stoichiometric to ferroelectric stillwellite-type LaBGeO5 crystalline phase, have been prepared by a two-step heat-treatment (first heat treatment: T1=670 °C, t1=10 h, second heat-treatment: T2, t2), and their second harmonic (SH) intensities have been examined using the Maker fringe method. The samples obtained by heat treatments at T2=720∼725 °C for t2=3 h show only surface crystallization and exh
