Due to the unique optical responses induced by vertical atomic asymmetry inside a monolayer. two-dimensional Janus structures have been conceived as promising building blocks for nanoscale optical devices. In this paper. second harmonic generation (SHG) in Janus transition metal chalcogenide oxide monolayers is systematically investigated by the first-principles calculations. https://www.bekindtopets.com/super-save-Vetscan-Flex-4-Rapid-Test-25-ct-super-buy/