웨이블릿에 기반한 비선형 분해 기법

학위논문(석사)--서울대학교 대학원 :전기.컴퓨터공학부,2006.Maste

기능, 데이타, 인터페이스분석에 의한 개념적 객체 based on function, data, and interface analysis

Maste

First-principles exploration of MgTi2O5 and MgV2O5 for CO2 capture and conversion

First-principles calculations were done to reveal the properties of MgTi2O5 and MgV2O5 for CO2 capture. The highest temperatures of MgTi2O5 and MgV2O5 for CO2 capture at different partial pressures (i.e., 0.1, 1, and 10 bar) were determined. CO2 was absorbed at higher temperatures by MgV2O5 than by MgTi2O5 at each partial pressure. Furthermore, the electronic properties of V-doped MgTi2O5 were theoretically examined to assess its potential use for photocatalytic CO2 conversion. The electronic properties of MgTi2O5 were found to be changed after V doping. Specifically, the band gap of MgTi2O5 was 2.75 eV and that of V-doped MgTi2O5 in the spin-up (down) channel was 0.48 (2.73 eV), showing the band gap decrease upon V doping

First-principles prediction of NO2 and SO2 adsorption on MgO/(Mg0.5Ni0.5)O/MgO(100)

Developing high-performance adsorbents for NO2 and SO2 is a significant step in reducing air pollution. In this study, using first-principles modeling, NO2 and SO2 adsorption on MgO/(Mg0.5Ni0.5)O/MgO(1 0 0) was theoretically predicted. Adsorption of NO2 was stronger than that of SO2 on the MgO/(Mg0.5Ni0.5)O/MgO(1 0 0) surface. Both structural and chemical changes were applied to MgO/(Mg0.5Ni0.5)O/MgO(1 0 0) in order to investigate strategies for improving the strength of adsorption of these gases on the MgO/(Mg0.5Ni0.5)O/MgO(1 0 0) system. NO2 and SO2 adsorption on MgO/(Mg0.5Ni0.5)O/MgO(1 0 0) was found to be tunable using the applied strain and certain promoters, such as Ca and Sr. The approach with the promoter more effectively enhanced the strength of NO2 and SO2 adsorption on MgO/(Mg0.5Ni0.5)O/MgO(1 0 0) than the approach with the applied strain. The interactions between the adsorbate (i.e., NO2 and SO2) and the MgO/(Mg0.5Ni0.5)O/MgO(1 0 0)) surface were further elucidated through an investigation of the density of states and Bader charge

다양한 모양의 금 나노입자 제조와 특성분석 및 응용

학위논문(박사) --서울대학교 대학원 :응용화학부,2007.Docto