http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
개별검색 DB통합검색이 안되는 DB는 DB아이콘을 클릭하여 이용하실 수 있습니다.
통계정보 및 조사
예술 / 패션
<해외전자자료 이용권한 안내>
- 이용 대상 : RISS의 모든 해외전자자료는 교수, 강사, 대학(원)생, 연구원, 대학직원에 한하여(로그인 필수) 이용 가능
- 구독대학 소속 이용자: RISS 해외전자자료 통합검색 및 등록된 대학IP 대역 내에서 24시간 무료 이용
- 미구독대학 소속 이용자: RISS 해외전자자료 통합검색을 통한 오후 4시~익일 오전 9시 무료 이용
※ 단, EBSCO ASC/BSC(오후 5시~익일 오전 9시 무료 이용)
A solidification of hypereutectic Al-30%Si alloy was studied under the condition of the forced fluid flow. The melt was stirred by a rapidly rotating graphite bar on whose surface the primary silicon was solidified. The average silicon content in the solid was more than 80% and the purity increased with the convection increased. The perfect Mixing Parameter(PMP) was introduced and used to rationalize the level of the purity achieved. Both the solute distributions in liquid and solid were influenced by fluid flows and affected the solidification behaviors. The temperature distributions in melts were also analogized by paraffin tests. The microstructural changes of the solid were showed along the position of the specimens and agreed well with its compositional change.
The effects of Zr addition on the microstructures and mechanical properties of 75wt.%Ag-25wt.%Pd alloy was studied. Grain size of the alloy was diminished with increasing amount of Zr addition, and it was notable when 0.2wt.% of Zr was added. when 0.6wt.% of Zr was added, coarse Pd₃Zr intermetallic compound(hexagonal, ??, ??) was precipitated in the matrix, and fine Pd₂Zr intermetallic compound(body centered tetragonal, ??, ??) could be seen by aging treatment at 450℃. Ultimate tensile strength of the alloy was increased with decreasing grain size until 0.2 wt.% Zr addition, but when an excess of Zr was added, ultimate tensile strength of the alloy was somewhat diminished despite of decreasing grain size. So, we concluded that the grain size of the 75wt.%Ag-25Wt.%Pd alloy was diminished by the Zr addition and mechanical properties were increased with decreasing grain size, and the optimum amount needed for hardening was 0.2 wt.%.
The effects of aging on the microstructures and mechanical properties of a 75wt.%Ag-25wt.%Pd alloy with various indium additions were studied. Tensile strength and hardness of the alloy increased with increasing aging temperature and time in the temperature range of 350 to 450℃. Similar trends were observed with increasing amount of In addition and precipitated InPd₃phase. Such features indicated that the alloy system considered in the study was age hardenable. In₂O₃oxide layers were observed to form at the outer surface of the specimen during heat treatment procedure. Based on the experimental observation, cracks were observed to form outer surface of the specimen followed by crack propagation along the grain boundary of the matrix, resulting in some decrease in the tensile strength.
다이아몬드 에미터는 디바이스 안정성이나 내구성에서 탁월한 성능을 가지므로 합성 다이아몬드 박막에 대한 관심이 크다. 이온주입의 효과가 고온 휠라멘트 화학기상증착법(HFCVD)법으로 성장된 다이아몬드 박막의 다이아몬드 품질에 미치는 영향을 연구하였다. 여기서는 붕소와 인의 이온을 고 에너지로 주입시켜, 이온 주입 전후의 다이아몬드의 구조적 변화를 분석하였다. Raman 스펙트럼 측정에 의하면 붕소 이온 주입된 시료는 많은 흑연 성분을 포함한 미약한 다이아몬드의 특성을 보이고 있으나, 인 이온 주입된 시료는 다이아몬드 구조를 나타내지 않는다. Auger 스펙트럼을 분석하면 붕소와 인 이온을 주입한 시료 모두가 표면에 심한 이온주입 훼손이 생겨 다이아몬드 특성을 잃은 것을 알 수 있다. There has been much interest in synthetic thin film diamond as the emitter materials because the diamond emitter can carry a crucial performance for the device stability and durability. Diamond films grown by hot filament chemical vapor deposition (HFCVD) have been studied to investigate the effect of ion implantation on diamond qualities. Here the diamond films were implanted with boron and phosphorus ions and analyzed their structural changes by implantations. From Raman spectra, the boron ion implanted samples still show a weakened diamond peak with high graphite component while the phosphorus ion implanted sample loses diamond structure. On tile other hand. their AES spectra at surface do not exhibit an obvious diamond shoulder, indicating the surface of ion implanted samples damaged by high fore implantation.