What is the reason why carbon nanotubes conduct electricity?

Carbon nanotube have recently emerged as an important nanomaterial with enhanced properties such as high electrical & thermal conductivity, aspect ratio, and toughness. To get electrons to flow through a semiconducting carbon nanotube.Carbon nanotubes conduct electricity better than metals. When electrons travel through metal there is some resistance to their movement. This resistance happens when electrons bump into metal atoms.They are considered the ideal candidate for electronic devices, biosensor hydrogen storage cells, electrostatic discharge, and electrical shielding applications.

Reference:https://www.quora.com/What-is-the-reason-why-carbon-nanotubes-conduct-electricity

How can distinguish that a nanoparticle is alloy or core-shell?

A core shell nanoparticle is composed by two phases, one in the core and another one covering it. The alloy ones are composed by only one.

The phases have different spectra for different wavelengths of electromagnetic radiation and electron beans. That means that the different phases are going to absorb different amounts of electrons at a given wavelength, controlled by the acceleration imposed to it by an electrical tension. This is what happens in electron microscopy.

In order to identify the two phases that behave differently with electrons, one possibility would be using transmission electron microscopy (TEM). TEM places the electron emitter and the detector on opposite sides of the sample. That means that the electrons must propagate through the sample, thus being absorbed in different intensities for different phases. That you result in a core shell structure showcased as a core covered with a material with a different visual aspect. The alloy one will have just one aspect. An example is the microscopy below, where the one on the left (a) is an alloy structure and the one on the right (b) in a core shell structure.

Is cancer treatment possible through nanotechnology? How?

Nanotechnology is already being used to help cure cancer, just not quite in the way your probably thinking. It is possible that one day we will be able to engineer nano robots that can go into the human body detect and destroy cancer cells by themselves but for now they use nanotechnology in their other tools to refine their ability to map out and treat cancerous regions. Nanotechnology allows accurate readings to made of tissue. Then nanoparticles then can be used to specifically target cancer cells minimizing damage to other tissue.

Reference: https://www.quora.com/Is-cancer-treatment-possible-through-nanotechnology-How