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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

On-surface synthesis of porous graphene nanoribbons containing nonplanar [14]annulene pores

Ajayakumar, M. R., Di Giovannantonio, Marco, Pignedoli, Carlo A., Yang, Lin, Ruffieux, Pascal, Ma, Ji, Fasel, Roman, Feng, Xinliang 22 January 2024 (has links)
The precise introduction of nonplanar pores in the backbone of graphene nanoribbon represents a great challenge. Here, we explore a synthetic strategy toward the preparation of nonplanar porous graphene nanoribbon from a predesigned dibromohexabenzotetracene monomer bearing four cove-edges. Successive thermal annealing steps of the monomers indicate that the dehalogenative aryl-aryl homocoupling yields a twisted polymer precursor on a gold surface and the subsequent cyclodehydrogenation leads to a defective porous graphene nanoribbon containing nonplanar [14]annulene pores and five-membered rings as characterized by scanning tunneling microscopy and noncontact atomic force microscopy. Although the C–C bonds producing [14] annulene pores are not achieved with high yield, our results provide new synthetic perspectives for the on-surface growth of nonplanar porous graphene nanoribbons.
52

Gold-bearing carbonate, sulfide, and silicate veining in igneous and sedimentary lithologies of the Helen Zone, Cove Deposit, Fish Creek Mountains, Nevada

Gilbow, Justin R. 10 June 2016 (has links)
No description available.

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