● Definition of plasma
Plasma is one of the four fundamental states of matter, along with solid, liquid, and gas. It is an ionized gas consisting of a collection of charged particles, including ions, electrons, and neutral atoms or molecules. Plasma can be found naturally in the universe in the form of stars, lightning, and auroras, but it can also be artificially created and controlled for
Introduction (What is plasma?)
1. Definition of plasma
Plasma is one of the four fundamental states of matter, along with solid, liquid, and gas. It is an ionized gas consisting of a collection of charged particles, including ions, electrons, and neutral atoms or molecules. Plasma can be found naturally in the universe in the form of stars, lightning, and auroras, but it can also be artif
temperature transformation diagram): 온도, 시간, 변태곡선
3) 표면 경화법
① 화학적 표면 경화법
ⅰ) 침탄법: 고체(목탄, 코우크스), 가스(CO,CO2,메탄,에탄,프로판), 침탄깊이 0.5~2mm
ⅱ) 시안화법: KCN, NaCN (청화법)
ⅲ) 질화법: NH3, 50~100 Hr, 자동차의 크랭크축, 캠, 펌프축 등에 사용. 질화층 0.4~0.8mm
* 특징
but we have nevertheless been polluting it for years.
The atmosphere can be divided vertically into four major layers : troposphere, stratosphere, mesosphere, and thermosphere.
Figure 2.1 The earth’s atmosphere is subdivided vertically into four major regions based on the air-temperature profile. The ozone layer that protects us from the sun’s UV radiation is in the stratosphere.
Sulfur Dioxide(SO2)
The release of SO2 to the atmosphere is the primary cause of acid rain in the world.
Fossil fuel combustion at electric power-generating plants accounts for about70% of
the emissions.
Coal, Oil, and all other fossil fuels naturally
contain some sulfur.
Volcanic eruptions are another more localized natural source of SO2
SO2 + OH. HSO3.
HS