ultrasonic signal can be obtained. In contact ultrasonic testing a thin film of oil, glycerin or water is generally used between the transducer and the test surface.
When scanning over the part or making precise measurements, an immersion technique is often used. In immersionultrasonic testing both the transducer and the part are immersed in the couplant, which is typically water. This method of
What is Bioenergy?
Bioenergy is renewable energy made available from materials derived from biological sources. Biomass is any organic material which has stored sunlight in the form of chemical energy. As a fuel it may include wood, wood waste, straw, manure, sugarcane, and many other byproducts from a variety of agricultural processes.
So, Why do we produce Bioenergy?
One reason governments
Abstract
Bioethanol is one of the alternative sources of oil resources which received attention with biodiesel. Many countries produce bioethanol from food sources such as corn and sugarcane, but it causes food-energy conflicts and farmland problem. So it needs to focus on new biomass which is sustainable, renewable, cost-effective and do not occurred any conflicts. Algae are one of the bioma
기존 접착제는 접착소재와 칩, 기판간의 열팽창계수 차이에 의한 박리, 크래킹 등이 문제.
CNT/epoxy 나노 복합체를 통해 해결.
하나의 탄소가 다른 탄소원자와 육각형 벌집무늬로 결합되어 튜브형태를 이루고 있는 물질
튜브의 직경이 나노미터(nm=10-9m) 수준으로 극히 작은 영역의 물질
멸균(sterilization)
대상물체에 존재하는 균을 완전히 박멸시키는 조작이다. 살균(균을 죽임)과는 조금 틀린 개념이다. 살균은 끓는 물(수증기)로 균을 죽이는 것을 말한다. 그러나 멸균처럼 균속의 포자등까지 죽이지는 못한다. 건조 ․일광조사 ․자외선 ․방사선 등은 소독에 이용된다. 0℃ 부