Is heat being released or absorbed physical or chemical changes

It can be either. If the object releasing or absorbing heat remains the same but in a different state the change was physical.Like an ice cube absorbing heat and melting. However, heat being released by a burning candle is chemical, as the wick burns and becomes smoke. A chemical change is results in a product with new properties.

nanotechnology is a powerful tool in biomaterials research as it creates numerous possibilities for the engineering of functional molecules. nano-bio refers to projected ability to incorporate biomimicry into various materials at nanoscale.