Would the control group not receive the treatment, or receive the same treatment that has been used before?

The control group receives either no treatment, a standard treatment whose effect is already known, or a placebo (a fake treatment).

characterization of nanoparticles is a critical step in nanomaterial production as it provides information of dimension, morphology, surface charge, distribution and degree of surface functionalization.

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a