Abstract: This article presents an efficient synthesis method for generating vortex beams based on donut-shaped orbital angular momentum (OAM) metasurfaces. It not only allows one to synthesize the ...

To transfer public lands into private hands efficiently, Congress passed a series of laws: the Homestead Act, the General Mining Act, the Desert Land Act and the Timber and Stone Act, for example.

The production of the neurotoxic methylmercury in the environment is partly controlled by the bioavailability of inorganic divalent mercury (Hg(II)) to anaerobic bacteria that methylate Hg(II). In ...