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Numerical Algorithms - In many engineering applications, it is necessary to minimize smooth functions plus penalty (or regularization) terms that violate smoothness and convexity. Specific... 相似文献
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Sustainable composites comprising scraps of high-density polyethylene (HDPE) and gypsum waste in proportions HDPE/gypsum 100/0, 50/50, 40/60, and 30/70 wt% were prepared. The morphology of the injected specimens was core-shell. Thermal, flammability, water absorption, and compression resistance were also evaluated. Progressively, the presence of gypsum increased the HDPE crystallinity and Tonset. Concerning the flammability, the composite 30/70 exhibited the burning rate three times lower than HDPE, indicating that the gypsum played a role as a flame retardant. The HDPE acted as waterproofing for gypsum. The compression resistance of the composites was similar to HDPE. 相似文献
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Luís Antônio Dantas Silva Fernanda Vieira Teixeira Raphael Caixeta Serpa Najla Locatelli Esteves Rayane Ramos dos Santos Eliana Martins Lima Marcílio Sérgio Soares da Cunha-Filho Adriano Antunes de Souza Araújo Stephânia Fleury Taveira Ricardo Neves Marreto 《Journal of Thermal Analysis and Calorimetry》2016,123(3):2337-2344
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Ana Salomé Pires João Batista Dina Murtinho Célia Nogueira Anna Karamysheva M. Luísa Ramos Bruce F. Milne Nuno Tiago Tavares José Gonçalves Ana Cristina Gonçalves Ana Margarida Abrantes Rui Soares Teresa Gonçalves Maria Filomena Botelho M. Elisa Silva Serra 《应用有机金属化学》2020,34(5):e5569
Platinum metal complexes are the most common chemotherapeutics currently used in cancer treatment. However, the frequent adverse effects, as well as acquired resistance by tumor cells, urge the development of effective alternatives. In the recent past, copper complexes with Schiff base ligands have emerged as good alternatives, showing interesting results. Accordingly, and in continuation of previous studies in this area, three new camphoric acid-derived halogenated salen ligands and their corresponding Cu (II) complexes were synthesized and their antitumor activity was evaluated in order to determine the influence of the type and number of halogens present (Br, Cl). The in vitro cytotoxic activity was screened against colorectal WiDr and LS1034 and against breast MCF-7 and HCC1806 cancer cell lines. The results proved the halogenated complexes to be very efficient, the tetrachlorinated Cu (II) complex being the most promising, presenting IC50 of 0.63–1.09 μM for the cell lines studied. The complex also shows selectivity to colorectal cancer cells compared to non-tumor colon cells. It is worth highlighting that the tetrachlorinated Cu (II) complex, our most efficient complex, shows a significantly more powerful antitumor effect than the reference drugs currently used in conventional chemotherapy. The halogenated salen and corresponding complexes were also screened for their antimicrobial activity against four bacterial species-Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa-and four fungal species-Candida albicans, Candida glabrata, Aspergillus fumigatus and Alternaria alternata. The compounds were found to exhibit moderate to strong antibacterial activity against the bacterial strains studied. NMR studies and theoretical calculations provided some insight into the structure of the ligands and copper complexes. Considering the results presented herein, our work validates the potential use of copper-based chemotherapeutics as alternatives for cancer treatment. 相似文献
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Helberth Júnnior Santos Lopes Lucas Rodrigues Ramos Edson Luiz Silva 《Applied biochemistry and biotechnology》2017,183(3):712-728
This study evaluated the production of hydrogen and propionic acid in an expanded granular sludge bed (EGSB) reactor by co-fermentation of cheese whey (CW) and crude glycerol (CG). The reactor was operated at hydraulic retention time (HRT) of 8 h by changing the CW/CG ratio from 5:1 to 5:2, 5:3, 5:4, and 5:5. At the ratio of 5:5, HRT was reduced from 8 to 0.5 h. The maximum hydrogen yield of 0.120 mmol H2 g COD?1 was observed at the CW/CG ratio of 5:1. Increasing the CG concentration repressed hydrogen production in favor of propionic acid, with a maximum yield of 6.19 mmol HPr g COD?1 at the CW/CG ratio of 5:3. Moreover, by reducing HRT of 8 to 0.5 h, the hydrogen production rate was increased to a maximum value of 42.5 mL H2 h?1 L?1at HRT of 0.5 h. The major metabolites were propionate, 1,3-propanediol, acetate, butyrate, and lactate. 相似文献