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We establish a new refinement of the right-hand side of the Hermite–Hadamard inequality for convex functions of several variables defined on simplices. 相似文献
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Josepha Yohanna de Jesus Eliane Santos de Carvalho Dantas Mairim Russo Serafini Paula dos Passos Menezes Juliana Cordeiro Cardoso Ricardo Luiz Cavalcanti Albuquerque-Jr Jivaldo do Rosário Matos Juliana Ferreira de Oliveira Irwin Rose Alencar de Menezes Francilene Amaral da Silva Adriano Antunes de Souza Araújo 《Journal of Thermal Analysis and Calorimetry》2016,123(3):2003-2012
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Ajit Kumar Singh Seulgi Ji Baghendra Singh Chittaranjan Das Heechae Choi Prashanth W. Menezes Arindam Indra 《Materials Today Chemistry》2022
Herein, we report a Mott-Schottky catalyst by entrapping cobalt nanoparticles inside the N-doped graphene shell (Co@NC). The Co@NC delivered excellent oxygen evolution activity with an overpotential of merely 248 mV at a current density of 10 mA cm–2 with promising long-term stability. The importance of Co encapsulated in NC has further been demonstrated by synthesizing Co nanoparticles without NC shell. The synergy between the hexagonal close-packed (hcp) and face-centered cubic (fcc) Co plays a major role to improve the OER activity, whereas the NC shell optimizes the electronic structure, improves the electron conductivity, and offers a large number of active sites in Co@NC. The density functional theory calculations have revealed that the hcp Co has a dominant role in the surface reaction of electrocatalytic oxygen evolution, whereas the fcc phase induces the built-in electric field at the interfaces with N-doped graphene to accelerate the H+ ion transport. 相似文献
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Dr. Jiawei Zhang Dr. Daisuke Ishikawa Dr. Michael M. Koza Prof. Dr. Eiji Nishibori Dr. Lirong Song Dr. Alfred Q. R. Baron Prof. Dr. Bo B. Iversen 《Angewandte Chemie (International ed. in English)》2023,62(13):e202218458
Loosely bonded (“rattling”) atoms with s2 lone pair electrons are usually associated with strong anharmonicity and unexpectedly low thermal conductivity, yet their detailed correlation remains largely unknown. Here we resolve this correlation in thermoelectric InTe by combining chemical bonding analysis, inelastic X-ray and neutron scattering, and first principles phonon calculations. We successfully probe soft low-lying transverse phonons dominated by large In1+ z-axis motions, and their giant anharmonicity. We show that the highly anharmonic phonons arise from the dynamic lone pair expression with unstable occupied antibonding states induced by the covalency between delocalized In1+ 5s2 lone pair electrons and Te 5p states. This work pinpoints the microscopic origin of strong anharmonicity driven by rattling atoms with stereochemical lone pair activity, important for designing efficient materials for thermoelectric energy conversion. 相似文献
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Dr. George Dhimba Prof. Dr. Alfred Muller Prof. Dr. Koop Lammertsma 《欧洲无机化学杂志》2023,26(25):e202300256
Cis-MoO2(nacnac)2 (nacnac=β-diketiminate) can be a viable chiral-at-metal catalyst when its two β-diketiminate (nacnac) ligands are N-substituted to prevent Λ⇌Δ racemization. Even simple methyl groups raise the barriers for racemization significantly for the Bailar, Rây-Dutt, Conte-Hippler, and Dhimba-Muller-Lammertsma (DML) twists to a respectable 28.5, 37.8, 30.5, and 25.1 kcal/mol, respectively, at ωB97X-D/6-311+G(2d,p) (LANL2DZ for Mo) including acetonitrile solvation. The lowest energy DML barrier increases to ΔGo=27.4 kcal/mol with N-substituted t-butyl groups. The nacnac ligands’ electronic and steric components to the racemization barriers are discussed. 相似文献
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Growth under Visible Light Increases Conidia and Mucilage Production and Tolerance to UV‐B Radiation in the Plant Pathogenic Fungus Colletotrichum acutatum 下载免费PDF全文
Henrique D. de Menezes Nelson S. Massola Jr Stephan D. Flint Geraldo J. Silva Jr Luciano Bachmann Drauzio E. N. Rangel Gilberto U. L. Braga 《Photochemistry and photobiology》2015,91(2):397-402
Light conditions can influence fungal development. Some spectral wavebands can induce conidial production, whereas others can kill the conidia, reducing the population size and limiting dispersal. The plant pathogenic fungus Colletotrichum acutatum causes anthracnose in several crops. During the asexual stage on the host plant, Colletototrichum produces acervuli with abundant mucilage‐embedded conidia. These conidia are responsible for fungal dispersal and host infection. This study examined the effect of visible light during C. acutatum growth on the production of conidia and mucilage and also on the UV tolerance of these conidia. Conidial tolerance to an environmentally realistic UV irradiance was determined both in conidia surrounded by mucilage on sporulating colonies and in conidial suspension. Exposures to visible light during fungal growth increased production of conidia and mucilage as well as conidial tolerance to UV. Colonies exposed to light produced 1.7 times more conidia than colonies grown in continuous darkness. The UV tolerances of conidia produced under light were at least two times higher than conidia produced in the dark. Conidia embedded in the mucilage on sporulating colonies were more tolerant of UV than conidia in suspension that were washed free of mucilage. Conidial tolerance to UV radiation varied among five selected isolates. 相似文献