13 research outputs found

    Identification of Catalytic Active Sites for Durable Proton Exchange Membrane Fuel Cell: Catalytic Degradation and Poisoning Perspectives

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    Recent progress in synthetic strategies, analysis techniques, and computational modeling assist researchers to develop more active catalysts including metallic clusters to single-atom active sites (SACs). Metal coordinated N-doped carbons (M-N-C) are the most auspicious, with a large number of atomic sites, markedly performing for a series of electrochemical reactions. This perspective sums up the latest innovative and computational comprehension, while giving credit to earlier/pioneering work in carbonaceous assembly materials towards robust electrocatalytic activity for proton exchange membrane fuel cells via inclusive performance assessment of the oxygen reduction reaction (ORR). M-Nx-Cy are exclusively defined active sites for ORR, so there is a unique possibility to intellectually design the relatively new catalysts with much improved activity, selectivity, and durability. Moreover, some SACs structures provide better performance in fuel cells testing with long-term durability. The efforts to understand the connection in SACs based M-Nx-Cy moieties and how these relate to catalytic ORR performance are also conveyed. Owing to comprehensive practical application in the field, this study has covered very encouraging aspects to the current durability status of M-N-C based catalysts for fuel cells followed by degradation mechanisms such as macro-, microdegradation, catalytic poisoning, and future challenges

    Evaluating Unenhanced Multidetector Computed Tomography of Kidneys, Ureters and Bladder (CT KUB) as the Initial Imaging Service in Suspected Acute Renal Colic Patients

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    Objective: To assess the role of unenhanced multidetector computed tomography (CT) of kidneys, ureters and bladder (KUB) in the initial imaging of suspected acute renal colic. Study Design: Retrospective longitudinal study. Place and Duration of Study: Combined Military Hospital, Kharian Pakistan, from Jan 2020 to Jan 2021. Methodology: One hundred and thirty-eight cases of suspected acute renal colic underwent CT-KUB. The demographic,radiological, clinical, and follow-up data were recorded for each patient. Results: There were 88(51.8%) males and 82(48.2%) females in the present study, with a mean age of 50.86±18.57 years. Out of 170 patients, only 138(81.17%) were indicated with acute findings, whereas 32(18.82%) individuals showed no acute findings.The mean stone size was found to be 4.77±0.98mm. Most of the stones had a location near the pelvic brim (n=47; 34.15%). Conclusion: The use of CT KUB should be encouraged for the evaluation of renal colic. Keywords: Acute renal colic, Computed tomography (CT), Computed tomography of Kidneys, ureter and bladder (CT-KUB)

    Fungal systematics and evolution : FUSE 6

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    Fungal Systematics and Evolution (FUSE) is one of the journal series to address the “fusion” between morphological data and molecular phylogenetic data and to describe new fungal taxa and interesting observations. This paper is the 6th contribution in the FUSE series—presenting one new genus, twelve new species, twelve new country records, and three new combinations. The new genus is: Pseudozeugandromyces (Laboulbeniomycetes, Laboulbeniales). The new species are: Albatrellopsis flettioides from Pakistan, Aureoboletus garciae from Mexico, Entomophila canadense from Canada, E. frigidum from Sweden, E. porphyroleucum from Vietnam, Erythrophylloporus flammans from Vietnam, Marasmiellus boreoorientalis from Kamchatka Peninsula in the Russian Far East, Marasmiellus longistipes from Pakistan, Pseudozeugandromyces tachypori on Tachyporus pusillus (Coleoptera, Staphylinidae) from Belgium, Robillarda sohagensis from Egypt, Trechispora hondurensis from Honduras, and Tricholoma kenanii from Turkey. The new records are: Arthrorhynchus eucampsipodae on Eucampsipoda africanum (Diptera, Nycteribiidae) from Rwanda and South Africa, and on Nycteribia vexata (Diptera, Nycteribiidae) from Bulgaria; A. nycteribiae on Eucampsipoda africanum from South Africa, on Penicillidia conspicua (Diptera, Nycteribiidae) from Bulgaria (the first undoubtful country record), and on Penicillidia pachymela from Tanzania; Calvatia lilacina from Pakistan; Entoloma shangdongense from Pakistan; Erysiphe quercicola on Ziziphus jujuba (Rosales, Rhamnaceae) and E. urticae on Urtica dioica (Rosales, Urticaceae) from Pakistan; Fanniomyces ceratophorus on Fannia canicularis (Diptera, Faniidae) from the Netherlands; Marasmiellus biformis and M. subnuda from Pakistan; Morchella anatolica from Turkey; Ophiocordyceps ditmarii on Vespula vulgaris (Hymenoptera, Vespidae) from Austria; and Parvacoccum pini on Pinus cembra (Pinales, Pinaceae) from Austria. The new combinations are: Appendiculina gregaria, A. scaptomyzae, and Marasmiellus rodhallii. Analysis of an LSU dataset of Arthrorhynchus including isolates of A. eucampsipodae from Eucampsipoda africanum and Nycteribia spp. hosts, revealed that this taxon is a complex of multiple species segregated by host genus. Analysis of an SSU–LSU dataset of Laboulbeniomycetes sequences revealed support for the recognition of four monophyletic genera within Stigmatomyces sensu lato: Appendiculina, Fanniomyces, Gloeandromyces, and Stigmatomyces sensu stricto. Finally, phylogenetic analyses of Rhytismataceae based on ITS–LSU ribosomal DNA resulted in a close relationship of Parvacoccum pini with Coccomyces strobi.http://www.sydowia.at/index.htmpm2021Medical Virolog

    Facile Synthesis of PdO.TiO<sub>2</sub> Nanocomposite for Photoelectrochemical Oxygen Evolution Reaction

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    The rapid depletion of fossil fuels and environmental pollution has motivated scientists to cultivate renewable and green energy sources. The hydrogen economy is an emerging replacement for fossil fuels, and photocatalytic water splitting is a suitable strategy to produce clean hydrogen fuel. Herein, the photocatalyst (PdO.TiO2) is introduced as an accelerated photoelectrochemical oxygen evolution reaction (OER). The catalyst showed significant improvement in the current density magnitude from 0.89 (dark) to 4.27 mA/cm2 (light) during OER at 0.5 V applied potential. The as-synthesized material exhibits a Tafel slope of 170 mVdec−1 and efficiency of 0.25% at 0.93 V. The overall outcomes associated with the photocatalytic activity of PdO.TiO2 demonstrated that the catalyst is highly efficient, thereby encouraging researchers to explore more related catalysts for promoting facile OER

    Recent progress in flexible Zn‐ion hybrid supercapacitors: Fundamentals, fabrication designs, and applications

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    Abstract One of the most exciting new developments in energy storage technology is flexible Zn‐ion hybrid supercapacitors (f‐ZIHSCs), which combine the high energy of Zn‐ion batteries with high‐power supercapacitors to satisfy the needs of portable flexible electronics. However, the development of f‐ZHSCs is still in its infancy, and there are numerous barriers to overcome before they can be widely implemented for practical applications. This review gives an up‐to‐date description of recent achievements and underlying concepts in energy storage mechanisms of f‐ZIHSCs and emphasizes the critical role of cathode, anode, and electrolyte materials systems in speeding the prosperity of f‐ZIHSCs. The innovative nanostructured‐based cathode materials for f‐ZIHSCs include carbon (e.g., porous carbon, heteroatom‐doped carbon, biomass‐derived porous carbon, graphene, etc.), metal‐oxides, MXenes, and metal/covalent‐organic frameworks, and other materials (e.g., activated carbon, phosphorene, etc.) are mainly focused. Afterward, the latest developments in flexible anode and electrolyte frameworks and impacts of electrolyte compositions on the electrochemical properties of f‐ZIHSC are elaborated. Subsequently, the advancements based on fabrication designs, including quasi‐solid‐state, micro, fiber‐shaped, and all climate‐changed f‐ZIHSCs, are discussed in detail. Lastly, a summary of current challenges and recommendations for the future progress of advanced f‐ZIHSC are addressed. This review article is anticipated to further understand the viable strategies and achievable approaches for assembling high‐performance f‐ZIHSCs and boost the technical revolutions on cathode, anode, and electrolytes for f‐ZIHSC devices

    Recent Advances in Transition Metal Tellurides (TMTs) and Phosphides (TMPs) for Hydrogen Evolution Electrocatalysis

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    The hydrogen evolution reaction (HER) is a developing and promising technology to deliver clean energy using renewable sources. Presently, electrocatalytic water (H2O) splitting is one of the low-cost, affordable, and reliable industrial-scale effective hydrogen (H2) production methods. Nevertheless, the most active platinum (Pt) metal-based catalysts for the HER are subject to high cost and substandard stability. Therefore, a highly efficient, low-cost, and stable HER electrocatalyst is urgently desired to substitute Pt-based catalysts. Due to their low cost, outstanding stability, low overpotential, strong electronic interactions, excellent conductivity, more active sites, and abundance, transition metal tellurides (TMTs) and transition metal phosphides (TMPs) have emerged as promising electrocatalysts. This brief review focuses on the progress made over the past decade in the use of TMTs and TMPs for efficient green hydrogen production. Combining experimental and theoretical results, a detailed summary of their development is described. This review article aspires to provide the state-of-the-art guidelines and strategies for the design and development of new highly performing electrocatalysts for the upcoming energy conversion and storage electrochemical technologies

    Fungal Systematics and Evolution: FUSE 6

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    With only 138,000 formally described fungal species (Kirk 2019) out of an estimated 2.2–3.8 million (Hawksworth & LĂŒcking 2017) to 6 million (Taylor et al. 2014), between 97.7 and 93.7% of fungal species are left to be characterized. These may be discovered in poorly studied habitats and geographic areas (e.g., tropical rainforests), as molecular novelties, within cryptic taxa, in fungal collections (e.g., new species hidden under current names and in unidentified material), and during studies of plant and insect collections (Hawksworth & LĂŒcking 2017, Wijayawardene et al. 2020). This large discrepancy between described and undescribed species needs to be addressed and recent work has shown that mycologists are nowhere near levelling off the curve in describing new species (Hyde et al. 2020b). Together with other series—Fungal Biodiversity Profiles (Rossi et al. 2020), Fungal Diversity Notes (Hyde et al. 2020a), Fungal Planet (Crous et al. 2020a), Mycosphere Notes (Pem et al. 2019), New and Interesting Fungi (Crous et al. 2020b)—the Fungal Systematics and Evolution series published by Sydowia contributes to a much-needed acceleration of discovery and description of fungal diversity. The present paper is the sixth contribution in the FUSE series published by Sydowia, after Crous et al. (2015), HernĂĄndez-Restrepo et al. (2016), KrisaiGreilhuber et al. (2017), Liu et al. (2018), and Song et al. (2019). Altogether, one family, six genera, 67 species, and 22 combinations have been introduced in the FUSE series.publishedVersio
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