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The reuse of industrial waste plays a crucial role in avoiding environmental impacts caused by incorrect disposal. Industrial production commonly generates huge volumes of wastes, and also increased costs associated with waste management and landfills maintenance. This study investigates the reuse of grit waste, from the cellulose kraft industry, as filler in gypsum plaster. Samples were prepared in proportions of 100/0, 85/15, 75/25 and 50/50 gypsum/grits and tested at 7, 14, 21 and 28 days. The mechanical resistance with incorporation of up to 25 wt% grit as filler is greater than that recommended in the regulatory standards. Flexural and compression strength tests for 15 wt% of gypsum replaced achieved values of 4.5 and 8.3 MPa, respectively. The manufacture of gypsum/grit is a viable solution for waste management and has great potential for enabling fabrication of gypsum plaster board, a low-cost and more sustainable new material.

Made available in DSpace on 2022-04-28T19:52:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Two red-emitting heteroleptic iridium(III) complexes (Ir-p and Ir-q) were synthesized and their photophysical and biological properties were analyzed. After their structures have been confirmed by several techniques, such as 1H NMR, 13C NMR, FT–IR, UV–Vis, and MALDI TOF analyses, their luminescence behavior was investigated in ethanol and PBS (physiological medium, pH ~ 7.4) solutions. Emission spectra of both complexes are dominated by 3MLCT states at room temperature in ethanolic solution, but at 77 K the Ir-q exhibits the 3LC as the dominant emission state. The Ir-q complex shows one of the highest emission quantum yields, 11.5%, for a red emitter based on iridium(III) complexes in aerated PBS solution, with color coordinates (x;y) of (0.712;0.286). Moreover, both complexes display high potential to be used as a biological marker with excitation wavelengths above 400 nm, high water solubility (Ir-p 1838 μmol L−1, Ir-q 7601 μmol L−1), and distinct emission wavelengths from the biological autofluorescence. Their cytotoxicity was analyzed in CHO-k1 cells by MTT assays, and the IC50 was estimated as being higher than 131 μmol L−1 for Ir-p, and higher than 116 μmol L−1 for Ir-q. Concentrations above 70% of viability were used to perform cell imaging by confocal and fluorescence microscopies and the results suggest that the complexes were internalized by the cell membrane and they are staining the cytoplasm region. School of Technology and Sciences São Paulo State University (Unesp), R. Roberto Simonsen, 305, SP Institute of Chemistry São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences São Paulo State University (Unesp), SP School of Technology and Sciences São Paulo State University (Unesp), R. Roberto Simonsen, 305, SP Institute of Chemistry São Paulo State University (Unesp) Institute of Biosciences Humanities and Exact Sciences São Paulo State University (Unesp), SP

Two red-emitting heteroleptic iridium(III) complexes (Ir-p and Ir-q) were synthesized and their photophysical and biological properties were analyzed. After their structures have been confirmed by several techniques, such as

Natural rubber membranes were fabricated using latex from Hevea brasiliensis trees (clone RRIM 600) by casting, and controlling the time and temperature of thermal treatment. Three temperatures were used: 65, 80 and 120 °C and the corresponding annealing times of 6, 8, 10 and 12 h. The centrifugation of the latex produces the constituent phases: solid rubber (F1), serum or protein components (F2) and bottom fraction (F3). The photoluminescence properties could be correlated with organic acid components of latex. Natural rubber membranes were used as the active substrate (reducing agent) for the incorporation of colloidal Au nanoparticles synthesized by in situ reduction at different times. The intensity of photoluminescence bands assigned to the natural rubber decreases with the increase in amount of nanoparticles present on the membrane surface. It can be assumed that Au nanoparticles may be formed by reduction of the Au cation reacting with functional groups that are directly related to photoluminescence properties. However, the quenching of fluorescence may be attributed to the formation of a large amount of metal nanostructures on the natural rubber surface.