http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
제7차 교육과정에 따른 실과 교과의 포털 사이트 개발을 위한 메타 콘텐츠의 구성체계에 관한 연구
송영건,유영길 한국기술교육학회 2002 한국기술교육학회지 Vol.2 No.2
The purpose of this study is to help the development and management of the portal site for the WBI of the practical arts education according to the 7th national education curriculum. The contents of the portal site were the same as the textbook of the practical arts. The site was consisted of four groups for each unit. For the design of the portal site, teacher's opinion was reflected. The problems and difficulties for searching the web site can be solved by using the portal site developed. The expecting effects of this research were as follows. First, teachers can have more time to prepare their class because of decreasing time to find the web site for using as the class material. Second, teachers can discriminate the site to help themselves because of evaluating the specific web site. Third, teachers can expect the real growth of the practical arts because of sharing the materials for communicating each other. Finally, everyone who works for education can use and understand the practical arts because of variety of information inside of the portal site.
A simple route for preparing Au/mesoporous silica yolk/shell particles for Au-catalyzed reactions
송영건,장호찬,이강택 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.7
We present a simple route to prepare mesoporous hollow silica particles containing an Au core, i.e., yolk/shell particles, by sol-gel and selective etching processes. Using tetraethoxysilane as a silica precursor, zinc acetate as a base catalyst, and cetyltrimethylammonium chloride as a soft template in the presence of Au nanoparticles, double-layered mesoporous shells were produced in one step. Elemental analysis showed that the inner shell consists of zinc silicate and the outer shell is pure silica. Au/mesoporous silica yolk/shell nanoparticles were obtained by selective etching of the zinc oxide phase with citrate buffer. The particle structure and composition were studied by transmission electron microscopy with energy disperse spectroscopy, UV-vis spectroscopy, X-ray diffraction, and nitrogen sorption experiments. Formation of double shells on the Au core in a single step was explained by a difference in the formation rates of the silica and zinc silicate phases. Au/mesoporous yolk/shell particles showed a high catalytic activity for reduction of 4-nitrophenol.