tothe environment also motivate the development of new energy. In this stream, the energy of nuclear fission and nuclear fusion, solar energy, subterranean heat energy, hydrogen energy, tidal energy and so on are researched with activity by scientists. Among them, hydrogen energy system supremely comes intothe spotlight. Hydrogen energy system bases an ideal principle which hydrogen is produce
5. Expanding On Topic – talking about natural disasters
Choose several questions among the given questions and discuss them with your partner.
(Use the phrases learned in speaking sections if you want)
1. What is a disaster?
2. Have you ever been in a disaster?
3. What kind of disasters is common in your country?
4. What can you do to prepare in advance for a disaster?
5. How mu
in large steel reactors that are designed towithstand very high pressures (up to one thousand atmospheres) and high temperatures (about 700°C or 1300°F). The reactors also resist attack by hydrogen gases which can corrode many metals, especially at high temperature and pressure. The catalyst in commercial ammonia synthesisis usually an iron oxide mixed with a small amount of additional "promo
of Korean tradition, lots of people have formed the thoughts that underclothes are for grandparents and it is really shameful to be noticed by others that the person is wearing the underclothes. As the result, even though people who try it and think highly of this product, they don’t dare to tell others and would never make recommendation for other friends, which also means an efficient promoti
ofthe eddy-mass diffusivity will be very much larger thanthe molecular diffusivity inthe turbulent core.
2. Fluid dynamics
- In fluid dynamics, an eddy isthe swirling of a fluid andthe reverse current created when the fluid flows past stir bar. This phenomenon is most visible behind large objects in swift-flowing fluids. The concept of eddy isoften used in turbulence flow.
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