TEM (a, b, and c) images of prepared mesoporous silica nanoparticles with mean outer diameter: (a) 20nm, (b) 45nm, and (c) 80nm. SEM (d) image corresponding to (b). The insets are a high magnification of mesoporous silica particle.
The Definition of a Monochrome Laser Printer. Monochrome laser printers are machines that print text and images from computers by using a laser beam to control where a single color is applied to paper. They're often faster than other types of printers and can generally produce large numbers of black-and-white documents cheaper than other printers.
Color printers are more expensive to operate since they use two ink cartridges (one color and one black ink) that need to be replaced after a certain number of pages. Users who don't have a specific need for color and who print a lot of pages will find a black-and-white printer cheaper to operate.