In this study, films of perfluoro-functionalized poly(3,4-ethylenedioxythiophene) [poly(EDOT-F)] were prepared directly through electropolymerization for use as catalysts for the oxygen reduction reaction (ORR), applying the rotating ring disk electrode technique. Poly(EDOT-F) operated catalytically through a two-electron and/or mixed pathway. Spinel Co3O4 nanospheres were introduced into poly(EDOT-F) to enhance its ORR performance and electron transfer number (n). Benefiting from its unique interconnected pore structure and its resemblance to the binder Nafion, poly(EDOT-F) could be used as a single replacement for both the binder and the carbon support required for the spinel Co3O4 nanospheres. The Co3O4/poly(EDOT-F) composite, when used as an electrode, exhibited a limiting current density of −4.761 mA cm–2 at 0.18 V (vs RHE) (cf. 20% Pt/C: −3.615 mA cm–2), an onset potential of 0.99 V (cf. 20% Pt/C: 0.938 V), and a half-wave potential of 0.628 V (cf. 20% Pt/C: 0.727 V) in 0.1 M aqueous KOH. The electron transfer number of the Co3O4/poly(EDOT-F) nanocomposite in the ORR was 3.84, suggesting a desirable four-electron pathway. This high electrocatalytic activity presumably resulted from the synergistic effect of the Co3O4 nanospheres and the poly(EDOT-F) polymer, which created many more active sites, enhanced the electron transfer kinetics, and eventually improved the ORR performance.

We report three new β-ketoenamine-linked covalent organic frameworks (COFs) prepared through Schiff-base [3 + 3] polycondensations of 1,3,5-triformylphloroglucinol (TFP-3OHCHO) with three tris(aminophenyl)-presenting derivatives—featuring amino, carbazole, and pyridine units, respectively under solvothermal conditions. The resultant TFP-COFs possessed high BET specific surface area up to 686 m2 g–1 and excellent crystallinity, which showed excellent electrochemical specific capacitances (up to 291.1 F g–1) and CO2 uptake efficiency up to 200 mg g–1 at 273 K. We propose the enhanced performance in supercapacitor and gas storage is owing to the conjugated enamine structures with redox-active triphenyl amino, carbazole, and pyridine moieties. In addition, we further investigate the formation mechanism of the spherical TFP-TPA COF by studying the morphological changes over time. The presence of more highly planar monomer units in the hexagonal structures of the resultant COFs led to stronger quadrupolar interaction with the included CO2 molecules.

We report three new β-ketoenamine-linked covalent organic frameworks (COFs) prepared through Schiff-base [3 + 3] polycondensations of 1,3,5-triformylphloroglucinol (TFP-3OHCHO) with three tris(aminophenyl)-presenting derivatives—featuring amino, carbazole, and pyridine units, respectively under solvothermal conditions. The resultant TFP-COFs possessed high BET specific surface area up to 686 m2 g–1 and excellent crystallinity, which showed excellent electrochemical specific capacitances (up to 291.1 F g–1) and CO2 uptake efficiency up to 200 mg g–1 at 273 K. We propose the enhanced performance in supercapacitor and gas storage is owing to the conjugated enamine structures with redox-active triphenyl amino, carbazole, and pyridine moieties. In addition, we further investigate the formation mechanism of the spherical TFP-TPA COF by studying the morphological changes over time. The presence of more highly planar monomer units in the hexagonal structures of the resultant COFs led to stronger quadrupolar interaction with the included CO2 molecules.

In this paper we report the construction of a hollow microtubular triazine‐ and benzobisoxazole‐based covalent organic framework (COF) presenting a sponge‐like shell through a template‐free [3+2] condensation of the planar molecules 2,4,6‐tris(4‐formylphenyl)triazine (TPT‐3CHO) and 2,5‐diaminohydroquinone dihydrochloride (DAHQ‐2HCl). The synthesized COF exhibited extremely high crystallinity, a high surface area (ca. 1855 m2 g−1), and ultrahigh thermal stability. Interestingly, a time‐dependent study of the formation of the hollow microtubular COF having a sponge‐like shell revealed a transformation from initial ribbon‐like crystallites into a hollow tubular structure, and confirmed that the hollow nature of the synthesized COF was controlled by inside‐out Ostwald ripening, while the non‐interaction of the crystallites on the outer surface was responsible for the sponge‐like surface of the tubules. This COF exhibited significant supercapacitor performance: a high specific capacitance of 256 F g−1 at a current density of 0.5 A g−1, excellent cycling stability (98.8 % capacitance retention over 1850 cycles), and a high energy density of 43 Wh kg−1. Such hollow structural COFs with sponge‐like shells appear to have great potential for use as high‐performance supercapacitors in energy storage applications.

In this study we synthesized two tetraphenyl-p-phenylenediaminebased covalent organic frameworks (TPPDA-TPPyr and TPPDATPTPE COFs) for potential use in high-performance electrochemical supercapacitors. This excellent performance arose from their structures containing redox-active triphenylamine derivatives and their high surface areas.

In this study we synthesized two tetraphenyl-p-phenylenediaminebased covalent organic frameworks (TPPDA-TPPyr and TPPDATPTPE COFs) for potential use in high-performance electrochemical supercapacitors. This excellent performance arose from their structures containing redox-active triphenylamine derivatives and their high surface areas.

One hundred and twenty‐nine isolates of Trichosporon jirovecii were isolated from the melanized exoskeleton as well as eyestalks, gills, muscle and haemolymph of red swamp crayfish (Procambarus clarkii) collected from the River Nile, during summer 2015. Isolates were similar morphologically, biochemically and genetically. Also, random amplified polymorphic DNA (RAPD) analysis exhibited no polymorphism among the tested isolates. Virulence factors such as chitinase, protease, lipase activities and biofilm formation were examined. Challenge test, using a representative isolate (Tj_ASU8), proved its pathogenicity against crayfish. Magnesium oxide nanoparticles had a good antifungal activity with a minimum fungicidal concentration of 8 mg/ml. To the best of our knowledge, this is the first report for isolation of T. jirovecii from red swamp crayfish, showing melanization, from the River Nile. We assume that infected crayfish may act as a vector for this fungus and can disseminate infection to all susceptible hosts in the vicinity.

One hundred and twenty‐nine isolates of Trichosporon jirovecii were isolated from the melanized exoskeleton as well as eyestalks, gills, muscle and haemolymph of red swamp crayfish (Procambarus clarkii) collected from the River Nile, during summer 2015. Isolates were similar morphologically, biochemically and genetically. Also, random amplified polymorphic DNA (RAPD) analysis exhibited no polymorphism among the tested isolates. Virulence factors such as chitinase, protease, lipase activities and biofilm formation were examined. Challenge test, using a representative isolate (Tj_ASU8), proved its pathogenicity against crayfish. Magnesium oxide nanoparticles had a good antifungal activity with a minimum fungicidal concentration of 8 mg/ml. To the best of our knowledge, this is the first report for isolation of T. jirovecii from red swamp crayfish, showing melanization, from the River Nile. We assume that infected crayfish may act as a vector for this fungus and can disseminate infection to all susceptible hosts in the vicinity.

One hundred and twenty‐nine isolates of Trichosporon jirovecii were isolated from the melanized exoskeleton as well as eyestalks, gills, muscle and haemolymph of red swamp crayfish (Procambarus clarkii) collected from the River Nile, during summer 2015. Isolates were similar morphologically, biochemically and genetically. Also, random amplified polymorphic DNA (RAPD) analysis exhibited no polymorphism among the tested isolates. Virulence factors such as chitinase, protease, lipase activities and biofilm formation were examined. Challenge test, using a representative isolate (Tj_ASU8), proved its pathogenicity against crayfish. Magnesium oxide nanoparticles had a good antifungal activity with a minimum fungicidal concentration of 8 mg/ml. To the best of our knowledge, this is the first report for isolation of T. jirovecii from red swamp crayfish, showing melanization, from the River Nile. We assume that infected crayfish may act as a vector for this fungus and can disseminate infection to all susceptible hosts in the vicinity.

The use of pesticides against the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) as a tool to control the pest has become an obstacle to the fresh agricultural products export to many countries that restrict pesticides residues. The effectiveness of three local strains of entomopathogenic fungi: Metarhizium anisopliae, Beauveria bassiana, and Paecilomyces lilacinus against the adult and immature stages of C. capitata was evaluated under laboratory conditions. Obtained results showed that M. anisopliae and B. bassiana were superior in its pathogenicity and potential to kill the pest than P. lilacinus. These results may be important to be used for the control of the pest in IPM program.