Quantities such as amount of substance, electrical current, mass, or luminous intensity are based on quantized entities, processes or other phenomena that can, at least in principle, be measured by counting. This contrasts with quantities which are, to the best of our current knowledge, of a ...
As adopt the full sealing device, it realizes the complete isolation of the crankcase from the cylinder; In addition, self-lubricating materials are used for piston ring to achieve the advanced oil-free lubrication. Since no sewage is discharged, this type of vac...