Publications by authors named "A Gayen"

New intrinsically unsymmetric aromatic donors (D) and acceptors (A) were designed to simplify the incorporation of a single reactive group. Naphthalene diimide (NDI) was desymmetrized by replacing one of the imide units with two nitro groups to yield 3,6-dinitronaphthalene monoimide (NMI(NO)); likewise, 3,6-dimethoxycarbazole (CBZ(OMe)) was designed as a 3-ring aromatic donor. Different derivatives of naphthalene monoimide (NMI) and carbazole (CBZ) were prepared, and charge-transfer complex formation between them was studied using NMR and UV-visible titrations; the estimated association constants () were compared with the common pair, NDI, and 1,5-dialkoxy naphthalene (DAN).

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Article Synopsis
  • The desert locust outbreak that started in the Horn of Africa between 2019-2020 caused significant crop damage in India after a 27-year gap, due to favorable climatic conditions for its spread.
  • The study evaluates the likelihood of future locust plagues in India using two statistical models—Weight-of-Evidence (WoE) and Frequency Ratio (FR)—by analyzing nine climatic factors.
  • Results indicate that a significant portion (42.7-52.8%) of western and central India is highly suitable for locusts, with certain areas being at higher risk, and the models used showed strong predictive accuracy.
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Dry reforming of methane (DRM) was extensively studied on Cu-doped LaNiO catalysts. The main findings of this work are as follows: (i) thermal switching of the catalyst phase between the parent perovskite and molecular-level nanocomposite of individual components formed during DRM, (ii) reusability of the catalyst with enhanced activity, and (iii) regeneration of the catalyst phase at a lower temperature than that required for the formation of the parent perovskite. The present investigation provides an extensive analysis and understanding of the DRM reaction using Cu-doped LaNiO compared to the result reported by Moradi , (, 2012, , 797-801) and hence provides new insights into its catalytic activity.

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We report a systematic Raman spectroscopy investigation of chemical vapor deposited 2D nonlayered CrS, with both linearly and circularly polarized light over a wide temperature range (5-300 K). Temperature-dependent Raman spectra exhibit a good linear relationship between the peak positions of the phonon modes and temperature. Angle-resolved polarized Raman spectra reveal the polarization-dependent optical response of in-plane and out-of-plane phonon modes.

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