It was 1981 and kids were mesmerized, flipping the colorful puzzle cubes in class, at home or with friends. After the eras of secret decoder rings and hula hoops, Rubik’s Cube was one of the most ...

Quantum dots of various sizes will fluoresce in different colours when excited by a purple laser pointer. They do not fluoresce when a red laser shines through them. Turn off the room lights. Using ...