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951.
Viksit Kumar H. J. Bharathkumar Sangram D. Dongre Rajesh Gonnade Kothandam Krishnamoorthy Sukumaran Santhosh Babu 《Angewandte Chemie (International ed. in English)》2023,62(47):e202311657
Recently, chiral and nonplanar cutouts of graphene have been the favorites due to their unique optical, electronic, and redox properties and high solubility compared with their planar counterparts. Despite the remarkable progress in helicenes, π-extended heterohelicenes have not been widely explored. As an anode in a lithium-ion battery, the racemic mixture of π-extended double heterohelical nanographene containing thienothiophene core exhibited a high lithium storage capability, attaining a specific capacity of 424 mAh g−1 at 0.1 A g−1 with excellent rate capability and superior long-term cycling performance over 6000 cycles with negligible fade. As a first report, the π-extended helicene isomer (PP and MM), with the more interlayer distance that helps faster diffusion of ions, has exhibited a high capacity of 300 mAh g−1 at 2 A g−1 with long-term cycling performance over 1500 cycles compared to the less performing MP and PM isomer and racemic mixture (150 mAh g−1 at 2 A g−1). As supported by single-crystal X-ray analysis, a unique molecular design of nanographenes with a fixed (helical) molecular geometry, avoiding restacking of the layers, renders better performance as an anode in lithium-ion batteries. Interestingly, the recycled nanographene anode material displayed comparable performance. 相似文献
952.
Shaifali Mishra Rajesh K. Yadav Satyam Singh Surabhi Chaubey Pooja Singh Chandani Singh Sarvesh Kumar Gupta Shivani Gupta Dhanesh Tiwary Tae Wu Kim 《Photochemistry and photobiology》2023,99(4):1080-1091
Photocatalysis is a defendable manner for production of several organic chemicals, energy and its storage from solar energy. For the evolution of metal free, cost-effective catalyst a 2D composite has been appear as a photocatalyst. Here, we had reported the synthesis of a light harvesting composite as a photocatalyst which was assembled by a poly-condensation mechanism between graphitic carbon nitride and tetrakis(4-nitrophenyl) porphyrin and the resulting composite manifest the excellent light harvesting properties, suitable energy band and low charge recombination. The photocatalyst [(NO2)4TPP@g-C3N4] enables the efficient photocatalytic production of nicotinamide adenine dinucleotide (NADH) from consumed NAD+ also the production of organic chemicals like 4-methoxybenzylimines from 4-methoxybenzylamines. The photocatalytic efficiency of the photocatalyst was estimated by the percentage of NADH regeneration and the percentage yield of organic transformations. It shows the tetrakis(4-nitrophenyl) porphyrin could enhance the charge transfer capacity of graphitic carbon nitride which shows excellent photocatalysis activities and organic transformations. 相似文献
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FTIR can assess multiple aspects of cell biochemistry and cytoplasmic components. The aim of this study was the FTIR examination of control and ethanol stressed Pachysolen tannophilus. The results of FTIR measurements were compared with those obtained by traditional biochemical methods. The data obtained with both FTIR and chemical methods, showed that ethanol stress led to changes in carbohydrate, lipids and proteins. This study demonstrates that the relative proportions of the major macromolecules contained in P. tannophilus cells and their changes in response to external stimuli can be determined rapidly, simultaneously and inexpensively using FTIR. The technique proved to be equally reliable to and less labour intensive than the more traditional chemical methods. 相似文献
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Rajesh Chitta Tibor Macko Robert Brüll Gerard Van Doremaele Lars‐Christian Heinz 《Journal of polymer science. Part A, Polymer chemistry》2011,49(8):1840-1846
Ethylene‐propylene‐diene terpolymers (EPDM) are generally amorphous and, therefore, do not crystallize from solution. Consequently, fractionation techniques based on crystallization, such as crystallization analysis fractionation or temperature rising elution fractionation, cannot be used to analyze their chemical composition distribution. Moreover, no suitable chromatographic system was known, which would enable to separate them according to their chemical composition. In this study, two different sorbent/solvent systems are tested with regard to the capability to separate EPDM‐terpolymers and ethylene‐propylene (EP)‐copolymers according to chemical composition. While porous graphite/1‐decanol system is selective towards ethylene and ethylidene‐2‐norbornene, carbon coated zirconia/2‐ethyl‐1‐hexanol is preferentially selective towards ethylene. Consequently, the earlier system enables to separate both EP copolymers and EPDM according to the chemical composition and the latter mainly according to the ethylene content. The results prove that the chromatographic separation in both sorbent/solvent systems is not influenced by molar mass of a sample or by its long chain branching. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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Rajesh Kharab Ravinder Kumar Pardeep Singh H.C. Sharma 《理论物理通讯》2008,49(4):1004-1008
We have studied the single-neutron stripping reaction induced by ^23O on carbon target at beam energy of 72 MeV//A with a motive to analyze its ground state structure. The partial stripping cross sections as well as longitudinal momentum distribution of ^22O core have been calculated within the framework of the eikonal approximation approach. Several core-neutron spin coupling configurations, corresponding to J^π= 1/2 + as ground state spin parity of ^23O, along with their suitable admixtures have been considered. The major outcome of the present work is that the s and d admixed configuration with a large contribution of s state seems to explain the longitudinal momentum distribution data more satisfactorily. 相似文献