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41.
Neighbourhood Sum Degree-Based Indices and Entropy Measures for Certain Family of Graphene Molecules
A topological index (TI) is a real number that defines the relationship between a chemical structure and its properties and remains invariant under graph isomorphism. TIs defined for chemical structures are capable of predicting physical properties, chemical reactivity and biological activity. Several kinds of TIs have been defined and studied for different molecular structures. Graphene is the thinnest material known to man and is also extremely strong while being a good conductor of heat and electricity. With such unique features, graphene and its derivatives have found commercial uses and have also fascinated theoretical chemists. In this article, the neighbourhood sum degree-based M-polynomial and entropy measures have been computed for graphene, graphyne and graphdiyne structures. The proper analytical expressions for these indices are derived. The obtained results will enable theoretical chemists to study these exciting structures further from a structural perspective. 相似文献
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43.
Awan Zahoor Maria Christy Yongbin Kim Anupriya Arul Yun Sung Lee Kee Suk Nahm 《Journal of Solid State Electrochemistry》2016,20(5):1397-1404
Platinum (Pt) and iridium (Ir) catalysts are well known to strongly enhance the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) kinetics, respectively. Pt–Ir-based bimetallic compounds along with carbon-supported titanium oxides (C–TiO2) have been synthesized for the application as electrocatalysts in lithium oxygen batteries. Transition metal oxide-based bimetallic nanocomposites (Pt–Ir/C–TiO2) were prepared by an incipient wetness impregnation technique. The as-prepared electrocatalysts were composed of a well-dispersed homogenous alloy of nanoparticles as confirmed by X-ray diffraction patterns and Fourier transform scanning electron microscopy analyses. The electrochemical characterizations reveal that the Pt–Ir/C–TiO2 electrocatalysts were bifunctional with high activity for both ORR and OER. When applied as an air cathode catalyst in lithium-air batteries, the electrocatalyst improved the battery performance in terms of capacity, reversibility, and cycle life compared to that of cathodes without any catalysts. 相似文献
44.
Design,Synthesis and Antimicrobial Evaluation of Novel Tricyclic Benzoxazine Fluoroquinolones under Conventional and Microwave Methods 下载免费PDF全文
B. Guruswamy R. Arul M. V. S. R. K. Chaitanya S. S. Praveen Kumar Darsi 《Journal of heterocyclic chemistry》2015,52(2):532-538
In view of obtaining some potential antimicrobial compounds, we have described synthesis of novel fluoroquinolones bearing 2‐(piperidin‐4‐yl)‐1H‐benzo[d]imidazole and evaluated for their antimicrobial activity. Alternatively, synthesis of these products was also demonstrated using microwave irradiation technique. The antimicrobial activity of newly synthesized compounds was evaluated against number of microorganisms and the activity is compared with highly active levofloxacin. 相似文献
45.
In this paper, the authors study the asymptotic behavior of solutions of second-order neutral type difference equations of the form
Δ2(yn+pyn−k)+f(n,yn−ℓ)=0,n