Figure 13 shows that cryo pump is cooling pump. It means this pump is cooling, liquefaction and store air, not pumping. Generally, it has 3 processes like condensation, absorption and trap at low temperature. The cooled air or molecules do not have any momentum so it is no possibility to heat any molecules. It means vacuum.
Cryo pump have High emission velocity and high emission capacity so it
사례 1. <1994년 9월 서울 종암동 임용석 내과>
1-1. 임순이 할머니에게서 나타나고 있는 중독 증상들은 ①난청(hearing loss), ②빈뇨(urinary frequency), ③갈증(thirst), ④진행성 중추신경계억제(progressive CNS depression), ⑤발열(hyperpyrexia), ⑥호흡수 증가(increased respiratory), ⑦빈맥(tarchycardia) 등 일곱 가지로 요약할 수
1. Pump에서의 Cavitation (공동현상) 에 대하여 기술하고 이로 생길 수 있는 문제점과 그 방지책에 대해 논하시오
- Cavitation이란
유체가 넓은 유로에서 좁을 곳으로 고속 유입하거나 벽면의 요철, 만곡부 등으로 흐름이 직선적이지 못할 때 유체는 저압이 되고 포화증기압보다 낮아지면 기화되어 기포가
2.3 C-V graph
The measured MOS capacitance (called gate capacitance) varies with the applied gate voltage.
① Measurement of C-V characteristics
-Apply any DC bias, and superimpose a small (15 mV) ac signal
-Generally measured at 1 MHz (highfrequency) or at variable frequencies between 1KHz to 1 MHz
-The dc bias VG is slowly varied to get quasi-continuous C-V characteristics
② C-V chara
1. Introduction
1) Definition of preservation and food-spoilage micro-organisms
Food preservation is the process of treating and handling food to stop or greatly slow down spoilage (loss of quality, edibility or nutritive value) caused or accelerated by micro-organisms. Some methods, however, use benign bacteria, yeasts or fungi to add specific qualities and to preserve food (e.g., cheese, wine