equally valid for spheres or circles, but one is chosen by convention. For aircraft or ships, the length or width can be used. For flow in a pipe or a sphere moving in a fluid the internal diameter is generally used today. Other shapes (such as rectangular pipes or non-spherical objects) have an equivalent diameter defined. For fluids of variable density (e.g. compressible gases) or variable visc
The atmosphere shields us from the sun's cancer-causing ultraviolet (UV) radiation and also moderates the earth's climate.
The atmosphere is obviously vital for human existence, but we have nevertheless been polluting it for years.
The atmosphere is obviously vital for human existence, but we have nevertheless been polluting it for years.
The atmosphere can be divided vertically into four m
remove large debris such as sticks, leaves, trash and other large particles
water stored in reservoirs for periods between a few days and many months to allow natural biological purification to take place
salts are treated with soda-ash (Na2CO3) to precipitate CaCO3 out utilizing the common-ion effect
chlorinated to minimize the growth of fouling organisms on the pipe-work and tanks
equal-weight basis, if carbon nanotubes reach the lungs, they are much more toxic than carbon black and can be more toxic than quartz, which is considered a serious occupational health hazard in chronic inhalation exposures.
• If fine NT dusts are present in a work environment, exposure protection strategies should be implemented to minimize human exposures.
Strong chemical and material
equal to the thickness of good quality paper, or the supporting table is lowered an equivalent amount, and the process is repeated. In order to build an object the controlling drawing for each layer changes very slightly.
Typical standard manufacturing methods are subtractive, that is material is removed from a base form by machining with a lathe, with a drill, by cutting, planing or broaching.
[열유체] The solid liquid flow(영문)
[환경화학] The Earth`s Atmosphere(영문)
건강, 안전, 환경문제와 Nanotechnology(영문)
