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Modified eco-friendly and biodegradable chitosan-based sustainable semiconducting thin films
Semiconducting materials are pivotal in various fields, such as solar cells, LEDs, photovoltaic cells, etc. A nature-friendly chitosan is a good film-forming, water-soluble polymer that is modified to a small band-gap polymer for various optoelectronic applications. Choline chloride:ethylene glycol:glycerin (1:1:1) deep eutectic solvent (DES)-modified activated carbon is incorporated into the chitosan matric and this composite is fabricated into thin films via spin coating methodology. The obtained films are subjected to multiple studies such as scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), impedance spectroscopy, and UVvis spectroscopy to perceive the thin-films microstructure, morphology, conductance, band gap, and optical nature. The integration of DES-modified activated carbon has significantly improved the charge transfer capacity of chitosan by reducing the band gap from 4.0 to 2.0 eV. These notable characteristics exhibited by the modified films can be key to sustainable semiconducting materials and have the potential to transform several optoelectronic applications. 2024 The Author(s). Polymers for Advanced Technologies published by John Wiley & Sons Ltd. -
Modified Genesio-Tesi systems with trigonometric functions and the Caputo fractional derivative
The new fractional-order Genesio-Tesi system is introduced, and its boundedness, stability of the equilibrium points, Lyapunov stability, uniqueness of the solution, and bifurcation are all discussed in this paper. Using the efficient predictor-corrector approach, we statistically analyze the Genesio-Tesi system in fractional order. The results effectively conceptualize and visualize the novel fractional order Genesio-Tesi systems that are suggested. When the systems order shifts from integer to fractional, the revolution around the fixed point increases. The chaotic character of the modified Genesio-Tesi system is comparable to that of the original Genesio system. The major changes were made to the Geensio-Tesi system by including the trigonometric functions, keeping the initial conditions and parameter values intact. The system is fractionalised with the help of Caputo fractional operator. In particular, the modified systems nature is more complex, which may aid in signal processing and secure communication. Future research on the modified Genesio-Tesi system can now proceed in light of this finding. This article offers a fresh approach to utilizing and thoroughly researching the Genesio-Tesi systems that have been provided. CSP - Cambridge, UK; I&S - Florida, USA, 2024 -
Modified Montmorillonite Catalysed Ultrasonic Assisted one-pot Synthesis of Novel 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones as Potential Anticancer Agents
The development of novel compounds with potential anticancer activity is imperative for combating the challenges posed by cancer. In this study, a modified montmorillonite based catalyst is employed for the synthesis of 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones, which are promising candidates for anticancer agents. Montmorillonite is modified using mixed metal oxides, typically Al2O3 and CeO2, by a facile approach followed by standard spectroscopic and electron microscopic characterizations. It is then employed for the one-pot synthesis of a series of 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones. The synthesis protocol, mediated by ultrasound, is simple, efficient, and environment friendly. The mixed metal oxide pillared montmorillonite catalyst exhibits high catalytic activity and selectivity, facilitating the formation of the desired compounds in good to excellent yields. The synthesized compounds are characterized using various spectroscopic techniques such as 1H NMR, 13C NMR and mass spectrometry. Furthermore, the anticancer activity of the synthesized compounds is evaluated against a series of cancer cell lines, revealing promising cytotoxic effects. The findings of this study highlight the potential of novel 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones as promising anticancer agent, warranting further investigation for their therapeutic potential. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Modified PredictorCorrector Method for the Numerical Solution of a Fractional-Order SIR Model with 2019-nCoV
In this paper, we analyzed and found the solution for a suitable nonlinear fractional dynamical system that describes coronavirus (2019-nCoV) using a novel computational method. A compartmental model with four compartments, namely, susceptible, infected, reported and unreported, was adopted and modified to a new model incorporating fractional operators. In particular, by using a modified predictorcorrector method, we captured the nature of the obtained solution for different arbitrary orders. We investigated the influence of the fractional operator to present and discuss some interesting properties of the novel coronavirus infection. 2022 by the authors. Licensee MDPI, Basel, Switzerland. -
Modified Rice Husk Silica from Biowaste: An Efficient Catalyst for Transesterification of Diethyl Malonate and Benzyl Alcohol
Abstract: Molybdenum and lanthanum oxide modified silica-based catalysts were prepared from the agricultural waste rice husk. These synthesized catalysts were characterized by various spectroscopic and non-spectroscopic techniques. The catalytic performance was investigated by transesterification reaction between diethyl malonate and benzyl alcohol in the liquid phase using modified silica as a heterogeneous catalyst. Molybdenum modified silica-based catalyst showed the highest conversion efficiency of 95.6% and selectivity of 96.8% for dibenzyl malonate. The reaction conditions were optimized to give maximum efficiency with the highest selectivity in a solvent-free green method. Graphic Abstract: [Figure not available: see fulltext.]. 2019, Springer Nature B.V. -
MOF derived cobalt-phospho-boride for rapid hydrogen generation via NaBH4 hydrolysis
Developing effective transition metal catalysts that can replace precious metal-based catalysts for hydrogen generation from the hydrolysis of chemical hydride has attracted extensive interest. This study focuses on synthesizing cobalt phospho-boride (CoPB) within a metal-organic framework (MOF) framework using hydrothermal and chemical reduction methodologies. Incorporating boron and phosphorous into Co-MOF enhances the hydrogen generation rate, reaching 1.8 L/min/g and 3.6 L/min/g for CoB-MOF and CoPB-MOF, respectively, during NaBH4 hydrolysis. Along with the nanostructured morphology of MOF, the electron modulation around Co-sites due to the presence of P and B creates a synergic effect to produce this high H2 generation rate and very low activation energy of 20.7 kJ/mol. The kinetic studies on NaBH4 hydrolysis reaction revealed zero-order kinetics with respect to NaBH4 concentration for CoPB-MOF, where porous morphology renders facile movement of BH4? ions to the active sites. The heat treatment at 773 K in the N2 atmosphere did not show any significant fall in the activity of CoPB-MOF, thus showcasing its robust nature. Moreover, the present catalyst also displayed recycling behavior with no signs of deactivation. 2024 Hydrogen Energy Publications LLC -
Moisture-Sensitive Fe2O3 Nanoparticle-Based Magnetic Soft Actuators
Multifunctional soft robots are emerging as a new-generation intelligent device for challenging environments. To meet the requirements of smart applications and soft robotics, developing a soft actuator capable of multiple functions and mechanical deformation is essential. In this study, we designed a free-standing magnetic soft actuator constructed from iron oxide (Fe2O3) nanoparticles and poly(vinyl alcohol) (PVA), that responds to both moisture and magnetic fields. We used computational modeling (density functional theory and ab initio molecular dynamics) to explain the experimental findings demonstrating the deformation and high-bending angle (?150), which is about twice as large under combined moisture and magnetic field exposure compared to their individual effect. Additionally, a flower-shaped soft robot was designed by using the continuous bending deformation of the actuator in response to moisture changes, performing directional bending in an ambient environment. These findings demonstrate the materials sensitivity to moisture and magnetic fields, opening up new possibilities for designing responsive structures in the smart device industry. 2024 American Chemical Society. -
Molecular architecture of PANI/V2O5/MnO2 composite designed for hydrogen evolution reaction
An ever increasing demand for energy has mandated scientists towards exploring innovative and environmentally friendly energy production techniques that can meet the needs of human beings and the world at large. Among the various techniques, hydrogen evolution reaction (HER) is a cost-effective and efficient method that produces hydrogen, a better fuel, for meeting our energy requirements. The large surface area, good redox capacity, high electroactivity, and tunable bandgap of polyaniline (PANI) makes it a preferred candidate for various energy-related applications. Incorporating mixed metal oxides into a polymer enhances its catalytic activities and can be used as an electrocatalyst for HER. In situ chemical oxidative polymerization method has been carried out to synthesize PANI/V2O5/MnO2 composite. The characterization studies of PANI/V2O5/MnO2 composite are done using XRD, FT-IR, BET, XPS, and FE-SEM analysis. The PANI/V2O5/MnO2 composite is used for linear sweep voltammetry studies and shows that it acts as an efficient electrocatalyst which gives an overpotential of 130 mV at 10 mA/cm2. The high electrocatalytic activity of the composite is due to the better surface phenomenon that is enhanced by the high porosity and surface area. The electrochemical impedance spectroscopy also shows lower charge transfer resistance for the PANI/V2O5/MnO2, confirming its excellent electroactivity. 90% of the current density is retained even after 7200 seconds, validating its stability. 2023 Elsevier B.V. -
Molecular detection of Kudoa septempunctata (Myxozoa: Multivalvulida) in sea water and marine invertebrates
The exportation of cultured olive flounder (Paralichthys olivaceus) in Korea has been recently decreasing due to the infections with a myxozoan parasite Kudoa septempunctata, and there is a strong demand for strict food safety management because the food poisoning associated with consumption of raw olive flounder harbouring K. septempunctata has been frequently reported in Japan. The life cycle and infection dynamics of K. septempunctata in aquatic environment are currently unknown, which hamper establishment of effective control methods. We investigated sea water and marine invertebrates collected from olive flounder farms for detecting K. septempunctata by DNA-based analysis, to elucidate infection dynamics of K. septempunctata in aquaculture farms. In addition, live marine polychaetes were collected and maintained in well plates to find any possible actinosporean state of K. septempunctata. The level of K. septempunctata DNA in rearing water fluctuated during the sampling period but the DNA was not detected in summer (June-July in farm A and August in farm B). K. septempunctata DNA was also detected in the polychaetes Naineris laevigata intestinal samples, showing decreased pattern of 40 to 0%. No actinosporean stage of K. septempunctata was observed in the polychaetes by microscopy. The absence of K. septempunctata DNA in rearing water of fish farm and the polychaetes N. laevigata intestinal samples during late spring and early summer indicate that the infection may not occur during this period. N. laevigata was suspected as the possible alternate invertebrate host of K. septempunctata, but the actinosporean stage was not found by well plate method and further studies will be necessary. This research provides important baseline information for understanding the infection dynamics of K. septempunctata in olive flounder farms and further establishment of control strategies. 2017 The Author(s). -
Molecular docking study, and ADMET analysis for the synthesized novel Zn(II) complexes as potential SARS-CoV-2 inhibitors
A new SARS-CoV-2 virus and its variants including omicron created a pandemic situation and caused more deaths in worldwide prompted many researchers to explore potential drug candidates. In this connection, we explored the first-of-its-kind report on computational studies such as molecular docking, and ADMET properties of Zn(II) complexes. The studies revealed the novel zinc complexes have high binding affinities with the SARS-CoV-2 spike glycoprotein (6vxx) alpha variant (7EKF), beta variant (7ekg), gamma variant (7EKC), delta variant (7V8B), and the omicron variant (7T9J). Molecular docking results of RMSD for SARS-CoV-2 beta variant (7ekg) and gamma variant (7EKC) are within excellent chemical stability in their protein-ligand complex state and should be effective in the biological system. ADME studies provided the better results with no adverse effect of toxicity related AMES along with absence of hepatotoxicity and skin sensitization when compared to Molnupiravir drug and it has a greater hepatotoxicity. This study could open further exploration of these novel zinc complexes for SARS-CoV-2 inhibition. (2024) DergiPark. -
Molecular level investigation on the impact of geometric isomers as fluorinated ligands in SIFSIX MOF for natural gas sweetening
In natural gas (NG), significant amounts of hydrogen sulfide (H2S) and carbon dioxide (CO2) are the most menacing contaminants that cause degradation of the purity of fuel. We considered fluorine-functionalized MOFs and employed cheaper and faster computational simulation techniques to understand the adsorption process. Hence, this includes structural optimization of newly designed fluorine-functionalized MOF with Density Functional Theory (DFT) and further Grand Canonical Monte Carlo (GCMC) simulation at room temperature on those MOFs for understanding in detail the adsorptive separation process on sour gases. However, the main emphasis has been made on the adsorptive separation of H2S gas from sour gas. Eventually, the fluorination of organic ligand in [(SiF6)Ni(1,2-di(pyridin-4-yl)ethyne)2] MOF has resulted in an excellent H2S/CO2 separation performance from NG because of the different geometrical isomers. The cis isomer of 1,2-di(pyridin-4-yl)ethyne as ligand in MOF, i.e., SIFSIX-Ni-dpe-3-cis, shows a high CO2 affinity than H2S; on the contrary, the trans isomer of 1,2-di(pyridin-4-yl)ethyne as ligand in MOF, i.e., SIFSIX-Ni-dpe-3-trans, has H2S selective over CO2 and CH4. So, the resulting affinity variation indicates that structural variation by the stereochemistry of ligands in MOF plays a significant role in NG purification, which is further validated through detailed molecular simulation analysis. 2022 Taylor & Francis Group, LLC. -
Molecular phylogenetics and character evolution in Haplanthodes (Acanthaceae), an endemic genus from peninsular India
Haplanthodes (Acanthaceae) is an Indian endemic genus with four species. It is closely related to Andrographis which is also mainly distributed in India. Haplanthodes differs from Andrographis by the presence of cladodes in the inflorescences, subactinomorphic flowers, stamens included within the corolla tube, pouched stamens and oblate pollen grains. To understand the phylogenetic relationship of Haplanthodes, Andrographis and Haplanthus, which are putatively closely related taxa, we used four plastid markers, matK, rbcL, psbA-trnH and trnGRto construct a molecular phylogeny. Our results established the monophyly of Haplanthodes and revealed a sister relationship to Andrographis and Haplanthus. Further, to understand the historical biogeography of the genus, we inferred the divergence time and performed an ancestral area reconstruction. Our analyses suggest that Haplanthodes evolved during Late Miocene 5.85 Ma (95%HPD: 2.1810.34 Ma) in peninsular India where it might have shared a common ancestor with Andrographis. To understand character evolution, the ancestral states of important morphological characters were inferred and discussed based on the equal rate model. The generic status of Haplanthus was not resolved due to incomplete sampling. 2022 Nordic Society Oikos. Published by John Wiley & Sons Ltd. -
Molecular Simulation Prediction on SO2 Gas Adsorption in Bipyridine Ligand-Based Square-Pillared MOFs
Increasing concentrations of toxic gases caused by the burning of fossil fuels necessitates the development of efficient porous materials for gas capture. Metal-organic frameworks (MOFs) have attracted a lot of attention as potential porous materials due to their effectiveness in adsorption of toxic gases. In particular, square-pillared metal-organic frameworks stand out for their exceptional potential toward gas adsorption, attributed to their remarkable surface area, thermal and chemical stabilities, and tunable properties. In this context, molecular simulations have been executed to observe and analyze the adsorption process of toxic flue gases such as SO2 and CO2 on MOFs. The present work deals with two different stable fluorinated MOFs named [Ni(4,4?-bipyridine)2(AlF5)]n (ALFFIVE-Ni-bipy) and [Ni(4,4?-bipyridine)2(NbOF5)]n, (NBOFFIVE-Ni-bipy) featuring AlF52- and NbOF52- anion pillars, respectively, comprising 4,4?-bipyridine as organic ligand and nickel as the central metal. The significance of utilizing the 4,4?-bipyridine ligands in these fluorinated MOFs enhances the SO2 gas adsorption and selectivity in the framework. Density functional theory has been implemented for geometry optimization, and Grand Canonical Monte Carlo simulations have been performed to forecast the adsorption isotherms. Both ALFFIVE-Ni-bipy (11.4 mmol/g) and NBOFFIVE-Ni-bipy (8.7 mmol/g) showed high SO2 adsorption capacity at 1 bar pressure, but ALFFIVE-Ni-bipy showed very good adsorption than other square-pillared MOFs and also unveiled good selectivity of SO2 gas. The coadsorption of binary SO2/CO2 and ternary SO2/CO2/N2 gas mixtures at ambient conditions indicated that the cost-effective aluminum (Al)-based square-pillared ALFFIVE-Ni-bipy is particularly suitable for acid gas adsorption. 2024 American Chemical Society -
Molecularly imprinted graphene based biosensor as effective tool for electrochemical sensing of uric acid
Graphene oxide based molecularly imprinted polymer was designed by incorporating vinyltrimethoxysilane into the layers of graphene oxide, which was copolymerized with functional monomers such as Itaconic acid (IA) and methyl methacrylate (MMA) was developed via bulk imprinting technique. The prepared polymer was studied for selective sensing the uric acid (UA) in blood serum. The electrode was constructed by modifying bare glassy carbon electrodes with the prepared molecularly imprinted polymer (MIP) via drop cast method. Electrochemical measurements were made by Cyclic voltammetric (CV) and Differential Pulse Voltammetric (DPV) response of the sensor. The physical and chemical properties of the resultant material will be characterized by FTIR spectroscopy, XRD and FESEM. The constructed sensor showed a regression coefficient (R2) of 0.9302 with limit of detection (LOD) of about 0.565 ??M. The developed sensor is reusable without any compromise in its selectivity. All the results confirm that the constructed biosensor requires no pre-treatment of samples and is suitable for real sample analysis. 2023 The Authors -
Molecularly imprinted PEDOT on carbon fiber paper electrode for the electrochemical determination of 2,4-dichlorophenol
A highly selective electrochemical sensor has been developed for the determination of the pesticide molecule, 2,4-dichlorophenol (2,4-DCP) using molecularly imprinted conducting polymer. 2,4-dichlorophenol imprinted polymer films were prepared by electropolymerising 3,4-ethylenedioxythiophene (EDOT) on surface of carbon fiber paper electrode (CFP) in presence of 2,4-dichlorophenol. Electrochemical over-oxidation was carried out for the controlled release of 2,4-DCP templates and to generate definite imprinting sites. Surface morphology of the imprinted electrode was analysed by Scanning Electron Microscopy-Energy Dispersive X-ray Spectrometry, Fourier Transform Infrared and Raman spectroscopy. In optimized conditions, the voltammetric sensor gave a linear response in the range of 0.21 nM 300 nM. The significantly low detection limit (0.07 nM) demonstrates the ultra-low sensitivity of the method. The imprinted sensor displayed higher affinity and selectivity towards the target 2,4-DCP over similar structural analogical interference than the non-imprinted sensor. MIP sensor was efficaciously employed for the selective determination of 2,4-DCP in real samples of water. 2020 Elsevier B.V. -
Molecularly Imprinted Scaffold Based on poly (3-aminobenzoic acid) for Electrochemical Sensing of Vitamin B6
Inadequate or excess consumption of Vitamin B6 (Vit B6) can have ill effects on the overall well-being of humans, thereby making it necessary to control their content and composition in the food we consume. A simple sensor is fabricated in this work for Vit B6 detection based on employing an electropolymerized molecularly imprinted polymer (MIP) of 3-amino benzoic acid. The poly (3- aminobenzoic acid) (P-(3ABA)) film was electrodeposited by potentiodynamic cycling of potential with and without Vit B6 (template) on carbon fiber paper electrode (CFP). The modified working electrodes were characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Field emission scanning microscopy, Energy dispersive X-ray spectrometry, Fourier Transform Infrared spectroscopy, Optical profilometry and X-ray photon electron spectroscopy were used for characterization. Nyquist plots revealed least charge transfer resistance at MIP/CFP than other control electrodes due to the molecularly imprinted sites. Under the optimized experimental conditions the developed MIP sensor showed a linear range 0.6 ?M to 700 ?M, with a detection limit of 0.010 ?M. Also a value of the imprinting factor (? = 3.50) indicates very good selectivity of the prepared sensor towards Vit B6 detection over its structurally similar analogues in the analysis of real sample matrices. 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. -
Monetary policy announcement and stock price behaviour: An event study with respect to India
Monetary policy in a developing country plays a significant role in achieving the objectives of macroeconomic policies. The Central Bank formulates and implements the monetary policy in a country which in turn facilitates the increase in growth rate, manages interest rates, and money supply in the economy. The primary objective of this paper is to test the semi-strong form of Efficient Market Hypothesis in the Indian Stock Market with respect to financial services industry by conducting an event study. The monetary policy announcements made from 11th March 2016 to 30th August 2019 are taken as the events. The event study methodology is conducted on 13 financial service companies listed in NSE Financial Services Index. The Average Abnormal Return (AAR) and Cumulative Average Abnormal Return (CAAR) are estimated using the daily closing price of the sample companies and Nifty. Two sample T-statistics are used to find the significance of the returns generated. The t-values of a majority of AARs and CAARs are significant suggesting that there is a scope for generating abnormal return by the investors on the event of the monetary policy announcement. It is found that the investors are able to earn abnormal profits which indicate that the Indian stock market is not efficient in the semi-strong form due to the slow absorption of information. IJSTR 2020. -
MONG: An extension to galaxy clusters
The presence of dark matter (DM), though well established by indirect evidence, is yet to be observed directly. Various DM detection experiments running for several years have yielded no positive results. In view of these negative results, we had earlier proposed alternate models by postulating a minimum gravitational field strength (minimum curvature) and a minimum acceleration. These postulates led to the modified Newtonian dynamics and modified Newtonian gravity (MONG). The observed flat rotation curves of galaxies were also accounted for through these postulates. Here, we extend these postulates to galaxy clusters and model the dynamical velocity-distance curve for a typical cluster such as the Virgo cluster. The radial velocities of galaxies in the Virgo cluster are also obtained through this model. Observations show an inconsistency in the Hubble flow at a mean cluster distance of 17 Mpc, which is expected in regions of high matter density. This decrease in velocity is predicted by our model of modified gravity (MONG). The radial velocity versus distance relation for galaxies in the Virgo cluster obtained using MONG is in agreement with observations. 2022 World Scientific Publishing Company. -
Monoclinic Y2O3: Ce nanophosphors synthesized by wet chemical precipitation method
UV emitting nanophosphors draws attention from many researchers currently due to the diverse applications ranging from UV LEDs to phototherapy. The current work is an investigation of monoclinic yttrium oxide doped with cerium synthesized by means of wet chemical precipitation at low temperature (90 C). Raman analysis and TEM experiments confirmed the formation of monoclinic phase and XPS analysis proves the presence of Ce3+ energy levels. UV experiments delivered strong absorption in the short UV region and photoluminescence experiments demonstrated the material's capability to emit in the long UV region. Surface area measurements by BET analysis established the relationship between the BET surface area and luminescence intensity. This emission range is suitable for therapeutical application especially for skin diseases which further extends the scope of the work. 2023 Elsevier Ltd and Techna Group S.r.l. -
Monoclinic yttrium oxide quantum dots surface modified by biotin for bioimaging applications
Semiconductor nanoparticles or quantum dots are one of the central topics of interest in material science research due to its size dependent physical and chemical characteristics and applications in different areas from display to biomedical fields. This work reports the first-time synthesis of biotin functionalized monoclinic yttrium oxide quantum dots at low temperature and its application in live cell imaging. The presence of biotin was confirmed through FTIR measurements. HRTEM analysis confirmed the formation of small spherical quantum dots with an average size of 3.8 nm. Zeta potential measurements gave a negative surface charge of -26.9 mV confirming colloidal stability. The quantum dots show sharp absorption in the short UV region and PL experiments delivered defect related intense blue fluorescence emission. The material is nontoxic to both normal (L929) and cancer (MCF 7) cells and the live cell imaging experiments performed on MCF 7 cells show specific binding to the cells and presented bright fluorescence emission from the cells thus confirming the applicability of the material in both display industry and cancer cell imaging. 2023 Elsevier B.V.