The theoretical capacity of silicon-based anode materials is more than 10 times higher than the capacity of graphite, so silicon can be used as an alternative to graphite anode materials. However, silicon has a much higher contraction and expansion rate due to lithiation of the anode material during the charge and discharge processes, compared to graphite anode materials, resulting in the pulverization of silicon particles during repeated charge and discharge. To compensate for the above issues, there is a growing interest in SiOx materials with a silica or carbon coating to minimize the expansion of the silicon. In this study, spherical silica (SiO2) was synthesized using TEOS as a starting material for the fabrication of such SiOx through heating in a reduction atmosphere. SiOx powder was produced by adding PVA as a carbon source and inducing the reduction of silica by the carbothermal reduction method. The ratio of TEOS to distilled water, the stirring time, and the amount of PVA added were adjusted to induce size and morphology, resulting in uniform nanosized spherical silica particles. For the reduction of the spherical monodisperse silica particles, a nitrogen gas atmosphere mixed with 5 % hydrogen was applied, and oxygen atoms in the silica were selectively removed by the carbothermal reduction method. The produced SiOx powder was characterized by FE-SEM to examine the morphology and size changes of the particles, and XPS and FT-IR were used to examine the x value (O/Si ratio) of the synthesized SiOx.
고령인구 증가로 인해 건강에 관심이 증가하고 있는 상황에서, 생리활성을 지니고 있는 소재들에 대한 관심이 높아지고 있다. 상황버섯은 항암효과가 있다고 소개된 바 있어, 식품보다 약재로 이용되는 빈도수가 많다. 항종양, 항염증 기능에 대한 연구는 보고되었으나 간기능 개선에 관련된 연구는 진행되지 않고 있다. 본 연구에서는 상황버섯 자실체 추출물과 균사체 배양액을 젖산균으로 발효한 1차, 2차 발효액의 간기능 개선효능을 확인하였다. Acetaminophen으로 유발된 간손상으로 인해 세포생존율이 79.9%로 감소하였으며 간기능의 지표인 ALT(82.0 ng/mL), AST(240.7 ng/mL), LDH(8.4 ng/mL)는 증가되었다. Acetaminophen과 상황 자실체 추출물 혹은 균사체 배양액을 발효한 시료를 동시 처리하여 세포생존율을 90.2~135.1%으로 증가하였으며 ALT는 55.3 ~ 90.9 ng/mL로, AST는 75.7 ~ 163.7 ng/mL로, LDH는 2.6 ~ 5.8 ng/mL로 감소되었다. 이러한 결과로 상황버섯 자실체 추출물 및 균사체 배양액 젖산균 발효물의 간 보호 및 간 기능 개선 효능이 있음을 확인하였다.
The effect of a-sexithiophene(α-6T) layers on the light emitting diode (LED) were studied. The α-6T was used for a buffer layer in electroluminescent (EL) devices. Enhanced carrier (hole) injection and improved emission efficiency were observed. Carrier injection characteristics were investigated as a function of α-6T later thickness. The efficiency of the electroluminescence was proportional to the thickness of α-6T layer. The highest efficiency was observed 600A of α-6T later, which was about 1.5 times higher than that of device without α-6T later. The device with a-6T showed an operation voltage lowered by 2V. The α-6T layer can substitute hole blocking layer, and control charge injection properties.