Eswaravara Prasadarao Komarala

Bio: Eswaravara Prasadarao Komarala is an academic researcher from Tel Aviv University. The author has contributed to research in topics: Catalysis & Materials science. The author has an hindex of 11, co-authored 15 publications receiving 327 citations. Previous affiliations of Eswaravara Prasadarao Komarala include Sungkyunkwan University & Indian Institute of Technology Bombay.

Effect of Fe and Mn Substitution in LaNiO3 on Exsolution, Activity, and Stability for Methane Dry Reforming

Abstract: Perovskites LaNi0.8Fe0.2O3 and LaNi0.8Mn0.2O3 were synthesized using the co-precipitation method by substituting 20 mol.% of the Ni-site with Fe and Mn, respectively. Temperature programmed reduction (TPR) showed that the exsolution process in the Fe- and Mn-substituted perovskites followed a two-step and three-step reduction pathway, respectively. Once exsolved, the catalysts were found to be able to regenerate the original perovskite when exposed to an oxygen environment but with different crystallographic properties. The catalytic activity for both materials after exsolution was measured for the methane dry reforming (DRM) reaction at 650 °C and 800 °C. Catalyst resistance against nickel agglomeration, unwanted phase changes, and carbon accumulation during DRM were analyzed using X-ray diffraction (XRD), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The presence Fe alloying in the catalyst particles after exsolution from LaNi0.8Fe0.2O3 led to a lower methane conversion compared to the catalyst derived from LaNi0.8Mn0.2O3 where no alloying occurred.

In-vitro evaluation of layered double hydroxide–Fe3O4 magnetic nanohybrids for thermo-chemotherapy

Abstract: Among two-dimensional nanomaterials, layered double hydroxides (LDHs) are of great interest in biomedical applications due to their unique properties and layered structure. Superparamagnetic iron oxide nanoparticles (Fe3O4) are also well known for their tailorable properties, high magnetization values and biocompatibility. The objectives of our current work are to combine LDHs with magnetic nanoparticles in order to widen the horizons of their applications in cancer therapy. This work undertakes a facile chemical approach for the fabrication of Fe3O4-conjugated Mg–Al layered double hydroxide magnetic nanohybrids (MNHs). The successful fabrication of these MNHs was evident from X-ray diffraction analysis, infrared spectroscopy, X-ray photoelectron spectroscopy, and zeta potential measurements. These MNHs were explored as possible heating platforms for magnetic hyperthermia as well as drug-delivery vectors to cancer cells. A high degree of drug-loading efficiency (∼99%) for doxorubicin (Dox), with ∼90% release in high proton environments was observed. In addition, the nature of the host–drug interactions was systematically investigated by fluorescence spectroscopy. These MNHs were seen to be biocompatible with murine fibroblast (L929) and human cervical (HeLa) cell lines. To exemplify the therapeutic performances of Dox-loaded MNHs, the IC50 (50% inhibitory concentration) value was also evaluated against HeLa cells. Calorimetric measurements revealed the specific absorption rates of 98.4 and 73.5 W g−1 for Fe3O4 and MNHs, respectively. In addition, the MNHs acted as a “cut-off switch” to maintain the hyperthermic temperature. As hyperthermia agents, these MNHs showed that a 20 min exposure to an alternating current magnetic field (ACMF) is adequate to inhibit the proliferation of HeLa cells and decrease the cell population significantly. In conclusion, the results established that these MNHs open up avenues of much more effective anticancer therapy.

Functional Graphene Nanomaterials Based Architectures: Biointeractions, Fabrications, and Emerging Biological Applications

Abstract: Functional graphene nanomaterials (FGNs) are fast emerging materials with extremely unique physical and chemical properties and physiological ability to interfere and/or interact with bioorganisms; as a result, FGNs present manifold possibilities for diverse biological applications. Beyond their use in drug/gene delivery, phototherapy, and bioimaging, recent studies have revealed that FGNs can significantly promote interfacial biointeractions, in particular, with proteins, mammalian cells/stem cells, and microbials. FGNs can adsorb and concentrate nutrition factors including proteins from physiological media. This accelerates the formation of extracellular matrix, which eventually promotes cell colonization by providing a more beneficial microenvironment for cell adhesion and growth. Furthermore, FGNs can also interact with cocultured cells by physical or chemical stimulation, which significantly mediate their cellular signaling and biological performance. In this review, we elucidate FGNs–bioorganism int...

First-principles calculations of electronic structure and spectra of strongly correlated systems: the LDA+U method

Abstract: The generalization of the Local Density Approximation (LDA) method for the systems with strong Coulomb correlations is presented which gives a correct description of the Mott insulators. The LDA+U method is based on the model hamiltonian approach and allows to take into account the non-sphericity of the Coulomb and exchange interactions. parameters. Orbital-dependent LDA+U potential gives correct orbital polarization and corresponding Jahn-Teller distortion. To calculate the spectra of the strongly correlated systems the impurity Anderson model should be solved with a many-electron trial wave function. All parameters of the many-electron hamiltonian are taken from LDA+U calculations. The method was applied to NiO and has shown good agreement with experimental photoemission spectra and with the oxygen Kα X-ray emission spectrum.

A review on catalyst development for dry reforming of methane to syngas: Recent advances

Abstract: The abrupt and massive deactivation of methane dry reforming catalysts especially Ni-based is still a monumental impediment towards its industrialization and commercialization for production of value-added syngas via Fischer-Tropsch process. The need for further and more critical understanding of inherent and tailored interactions of catalyst components for performance and stability enhancement during reforming reaction cannot be over-emphasized. This review provides a contemporary assessment of progresses recorded on synergistic interplay among catalyst components (active metals, support, promoters and binders) during dry reforming using state-of-the-art experimental and theoretical techniques. Advancements achieved during interplay leading to improvements in properties of existing catalysts and discovery of novel ones were stated and expatiated. Reaction pathways, catalytic activities, selection of appropriate synthesis route and metal/support deactivation via sintering or carbon deposition have over time been successfully studied and explained using information from these crucial component interactions. This perspective describes the roles of these interactions and their applications towards development of robust catalysts configurations for successful industrial applications.