Design of assemblies based on polymer-coated quantum dots and organic dye

During last years, photophysical properties of complexes of semiconductor quantum dots (QDs) with organic dyes have attracted increasing interest. The development of different assemblies based on QDs and organic dyes allows to increase the range of QDs applications, which include imaging, biological sensing and electronic devices.1 Some studies demonstrate energy transfer between QDs and organic dye in assemblies.2 However, for electronic devices purposes, a polymeric matrix is required to enhance QDs photostability. Thus, in order to attach the QDs to the polymer surface it is necessary to chemically modify the polymer to induce electronic charges and stabilize the QDs in the polymer. The present work aims to investigate the design of assemblies based on polymer-coated QDs and an integrated acceptor organic dye. Polymethylmethacrylate (PMMA) and polycarbonate (PC) were used as polymeric matrices, and nile red as acceptor. Additionally, a PMMA matrix modified with 2-mercaptoethylamine is used to improve the attachment between both the donor (QDs) and the acceptor (nile red), as well as to induce a covalent bond between the modified PMMA and the QDs. An enhancement of the energy transfer efficiency by using the modified PMMA is expected and the resulting assembly can be applied for energy harvesting.

30 minutes of physical activity a day is good for your health

This poster promotes the message that 30 minutes of moderate physical activity a day has substantial health benefits, and highlights the fact that you don’t have to do 30 minutes all in one go.

Minutes of the Board of Directors of the Port Hope, Lindsay and Beaverton Railway Company held in Port Hope

Minutes of the Board of Directors of the Port Hope, Lindsay and Beaverton Railway Company held in Port Hope, Aug 9, 1855.

Minutes of a meeting of the members of the Long Point Company

Minutes of a meeting of the members of the Long Point Company (1 page, printed). This has the names J.I. Mackenzie, secretary and Horatio Hathaway, chairman on the bottom of the page, Oct. 28, 1880.

Extract from the minutes of the board of directors of the Long Point Company

Extract from the minutes of the board of directors of the Long Point Company (3 pages, printed). This includes private instructions for Alfred March, steward at Long Point. This has the names J.I. Mackenzie, secretary-treasurer and Joseph A. Woodruff, president on the bottom of the page, Feb. 25, 1882.

Extract from the minutes of a session of the Provisional Municipal Council of the County of Welland

Extract from the minutes of a session of the Provisional Municipal Council of the County of Welland held on Nov. 3rd, 1855. It was decided that the petition of Andrew Drew and others be laid over until the engineer could make a survey of the premises and report to the council. This was signed by Dexter Deverardo, 1855

Notice from Dexter Deverardo regarding minutes of the meeting of the Municipal Council of the County of Welland

Notice from Dexter Deverardo regarding minutes of the meeting of the Municipal Council of the County of Welland that was held May 21, 1857. It was moved that the warden and clerk be requested to procure a plan of the marsh lands tract, May, 1857.