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排序方式: 共有308条查询结果,搜索用时 15 毫秒
1.
Subhajit Chakraborty Risov Das Mohd Riyaz Kousik Das Ashutosh Kumar Singh Debabrata Bagchi Chathakudath P. Vinod Sebastian C. Peter 《Angewandte Chemie (International ed. in English)》2023,62(9):e202216613
We present surface reconstruction-induced C−C coupling whereby CO2 is converted into ethylene. The wurtzite phase of CuGaS2. undergoes in situ surface reconstruction, leading to the formation of a thin CuO layer over the pristine catalyst, which facilitates selective conversion of CO2 to ethylene (C2H4). Upon illumination, the catalyst efficiently converts CO2 to C2H4 with 75.1 % selectivity (92.7 % selectivity in terms of Relectron) and a 20.6 μmol g−1 h−1 evolution rate. Subsequent spectroscopic and microscopic studies supported by theoretical analysis revealed operando-generated Cu2+, with the assistance of existing Cu+, functioning as an anchor for the generated *CO and thereby facilitating C−C coupling. This study demonstrates strain-induced in situ surface reconstruction leading to heterojunction formation, which finetunes the oxidation state of Cu and modulates the CO2 reduction reaction pathway to selective formation of ethylene. 相似文献
2.
A simple method for preparing redispersible nanofibers from sugar beet residue and their use as a well-dispersed reinforcement for a polyvinyl alcohol (PVA) matrix is reported. It is known that the redispersion of dried cellulose nanofibers is difficult because of the formation of strong hydrogen bonds between the nanofibers. The results show that the properties of the initial sugar beet nanofiber suspension can be recovered without the use of chemical modification or additives with higher pectin and hemicellulose content. Undried and redispersed nanofibers with and without pectin were used as nanocomposite reinforcement with PVA. The redispersed nanofibers were as good reinforcements as the undried nanofibers. The tensile strength and elastic modulus of the nanocomposites with the redispersed sugar beet nanofibers were as good as those of the nanocomposites with undried nanofibers. Interestingly, the nanofiber dispersion in the PVA matrix was better when sugar beet nanofibers containing pectin and hemicellulose were used as reinforcements. 相似文献
3.
Weber Jeffrey K. Morrone Joseph A. Bagchi Sugato Pabon Jan D. Estrada Kang Seung-gu Zhang Leili Cornell Wendy D. 《Journal of computer-aided molecular design》2022,36(5):391-404
Journal of Computer-Aided Molecular Design - We here present a streamlined, explainable graph convolutional neural network (gCNN) architecture for small molecule activity prediction. We first... 相似文献
4.
Keshab Chandra Bagchi 《Applied Scientific Research》1966,16(1):131-140
Summary The flow of a Reiner-Rivlin fluid between two coaxial porous circular cylinders has been studied. The inner cylinder performs a steady oscillation while the outer one is fixed.The exact solution of this problem has been obtained and approximate solutions for the two extreme cases, very small and very high frequencies, have been derived. 相似文献
5.
6.
Piyali Bagchi Khatua Ujjal Debnath 《International Journal of Theoretical Physics》2012,51(12):3701-3720
In this work, we have considered Cardassian Universe in Ho?ava-Lifshitz gravity. Four types of Cardassian Universe models i.e., polytropic/power law, modified polytropic, exponential and modified exponential models have been considered for accelerating models. The natures of statefinder parameters, deceleration parameter, Om diagnostic and EoS parameters have been investigated for all types of Cardassian models in Ho?ava-Lifshitz gravity. 相似文献
7.
Kumar K. Santhosh Siddaiah V. Lilakar J. D. Sunanda K. Ganesh A. 《Russian Journal of Organic Chemistry》2020,56(11):2014-2021
Russian Journal of Organic Chemistry - An efficient and simple continuous-flow synthetic protocol for novel quinoline-tethered pyrazoline derivatives, which involves condensation of... 相似文献
8.
We have considered a model of two component mixture i.e., mixture of Chaplygin gas and barotropic fluid with tachyonic field.
In the case, when they have no interaction then both of them retain their own properties. Let us consider an energy flow between
barotropic and tachyonic fluids. In both the cases we find the exact solutions for the tachyonic field and the tachyonic potential
and show that the tachyonic potential follows the asymptotic behavior. We have considered an interaction between these two
fluids by introducing a coupling term. Finally, we have considered a model of three component mixture i.e., mixture of tachyonic
field, Chaplygin gas and barotropic fluid with or without interaction. The coupling functions decays with time indicating
a strong energy flow at the initial period and weak stable interaction at later stage. To keep the observational support of
recent acceleration we have considered two particular forms (i) Logamediate Scenario and (ii) Intermediate Scenario, of evolution
of the Universe. We have examined the natures of the recent developed statefinder parameters and slow-roll parameters in both
scenarios with and without interactions in whole evolution of the universe. 相似文献
9.
A palladium catalyzed domino intermolecular Suzuki followed by intramolecular Heck coupling is described. This strategy afforded a novel and convenient synthesis of various 9-fluorenylidene derivatives in one-pot under relatively mild reaction condition. 相似文献
10.
Arnab Bagchi Yu‐Hsuan Huang Z. F. Xu P. Raghunath Yuan T. Lee Chi‐Kung Ni M. C. Lin Yuan‐Pern Lee 《化学:亚洲杂志》2011,6(11):2961-2976
The photodissociation of gaseous benzaldehyde (C6H5CHO) at 193, 248, and 266 nm using multimass ion imaging and step‐scan time‐resolved Fourier‐transform infrared emission techniques is investigated. We also characterize the potential energies with the CCSD(T)/6‐311+G(3df,2p) method and predict the branching ratios for various channels of dissociation. Upon photolysis at 248 and 266 nm, two major channels for formation of HCO and CO, with relative branching of 0.37:0.63 and 0.20:0.80, respectively, are observed. The C6H5+HCO channel has two components with large and small recoil velocities; the rapid component with average translational energy of approximately 25 kJ mol?1 dominates. The C6H6+CO channel has a similar distribution of translational energy for these two components. IR emission from internally excited C6H5CHO, ν3 (v=1) of HCO, and levels v≤2, J≤43 of CO are observed; the latter has an average rotational energy of approximately 13 kJ mol?1 and vibrational energy of approximately 6 kJ mol?1. Upon photolysis at 193 nm, similar distributions of energy are observed, except that the C6H5+HCO channel becomes the only major channel with a branching ratio of 0.82±0.10 and an increased proportion of the slow component; IR emission from levels ν1 (v=1) and ν3 (v=1 and 2) of HCO and v≤2, J≤43 of CO are observed; the latter has an average energy similar to that observed in photolysis at 248 nm. The observed product yields at different dissociation energies are compared to statistical‐theory predicted results based on the computed singlet and triplet potential‐energy surfaces. 相似文献