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PEDOT-Doped Mesoporous Nanocarbon Electrodes for High Capacitive Aqueous Symmetric Supercapacitors
Poly(3,4-ethylenedioxythiophene) (PEDOT) and PEDOT-functionalized carbon nanoparticles (f-CNPs) were synthesized by in situ chemical oxidative polymerization and pyrolysis methods. f-CNP-PEDOT nanocomposites were prepared by varying the concentration of PEDOT from 1 to 20% by weight (i.e., 1, 2.5, 5, 10, and 20 wt%). Several characterization techniques, such as field-emission scanning electron microscopy (FESEM), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), N2 BrunauerEmmettTeller (BET) and BarrettJoynerHalenda (BJH) analyses, as well as cyclic voltammetry (CV), galvanostatic charge discharge (GCD), and electrochemical impedance spectroscopy (EIS), were applied to investigate the morphology, the crystalline structure, the N2 adsorption/desorption capability, as well as the electrochemical properties of these new synthesized nanocomposite materials. FESEM analysis showed that these nanocomposites have defined porous structures, and BET surface area analysis showed that the standalone f-CNP exhibited the largest surface area of 801.6 m2/g, whereas the f-CNP-PEDOT with 20 wt% exhibited the smallest surface area of 116 m2/g. The BJH method showed that the nanocomposites were predominantly mesoporous. CV, GCD, and EIS measurements showed that f-CNP functionalized with 5 wt% PEDOT had a higher capacitive performance compared to the individual f-CNPs and PEDOT constituents, exhibiting an extraordinary specific capacitance of 258.7 F/g, at a current density of 0.25 A/g, due to the combined advantage of enhanced electrochemical activity induced by PEDOT doping, and highly developed porosity of f-CNPs. Symmetric aqueous supercapacitor devices were fabricated using the optimized f-CNP-PEDOT doped with 5 wt% of PEDOT as active material, exhibiting a high capacitance of 96.7 F/g at 1.4 V, holding practically their full charge, after 10,000 chargedischarge cycles at 2 A/g, thus providing the highest electrical electrodes performance. Hereafter, this work paves the way for the potential use of f-CNP-PEDOT nanocomposites in the development of high-energy-density supercapacitors. 2024 by the authors. -
XGBoost Design byMulti-verse Optimiser: An Application forNetwork Intrusion Detection
This article presents the results of an experimental study, which aims to assess the efficiency of the performance of a novel multi-verse optimiser algorithm for the optimisation of parameters of a network intrusion detection system event classifier. The article gives an overview of computer network intrusion detection, outlines common issues faced by software solutions tackling this problem, and proposes using a machine learning algorithm to help solve some of these common issues. An XGBoost classification model with a multi-verse optimisation algorithm for adaptive search and optimisation is used to solve the network intrusion detection system event classifier hyper-parameter optimisation problem. Results of this experimental study are presented and discussed, the improvements compared to previous solutions is shown, and a possible direction of future work in this domain is given in the conclusion. 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Relevance of psychophysiological and emotional features for the analysis of Human behavior-A Survey
With fresh development in the area of artificial intelligence and machine learning, the analysis of human physiological and psychological behavior has increased greater attention around the world. In this paper, we have provided a detailed survey of the approaches used for human behavior detection considering different modalities with physiological behavior, psychological behavior, and emotion detection with the help of sensors EEG, ECG, GSR, and temperature. At long last, it finishes up with the results of this study and represents the thoughts for future exploration in the zone of human behavior understanding. A rundown and comparison among the ongoing investigations done, that uncovers the currently existing issues and the future work has been examined. The Electrochemical Society -
Prediction of Users Behavior on the Social Media Using XGBRegressor
The previous decennium has seen the growth and advance with respect to social media and such that has violently also immensely expanded to infiltrate each side of user lives. In addition, mobile network empowers clients to admittance to MSNs at whenever, anyplace, for any character, including job and gathering. Accordingly, the association practices among clients and MSNs are getting completer and more confounded. The goal of this paper is to examine the number of followers, likes, and post for Instagram users. The dataset yielded several fundamental features, which were used to create the model with multimedia social networks (MSNs). Then, natural language processing (NLP) features should be added and finally incorporate features derived in distinction to a machine learning technique like XGBRegressor with TF-IDF technique. We use two performance indicators to compare the different models: root mean square error (RMSE) and the R2 value. We achieved average accuracy using XGBRegressor which is 82%. 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Multi-layer Stacking-based Emotion Recognition using Data Fusion Strategy
Electroencephalography (EEG), or brain waves, is a commonly utilized bio signal in emotion detection because it has been discovered that the data recorded from the brain seems to have a connection between motions and physiological effects. This paper is based on the feature selection strategy by using the data fusion technique from the same source of EEG Brainwave Dataset for Classification. The multi-layer Stacking Classifier with two different layers of machine learning techniques was introduced in this approach to concurrently learn the feature and distinguish the emotion of pure EEG signals states in positive, neutral and negative states. First layer of stacking includes the support vector classifier and Random Forest, and the second layer of stacking includes multilayer perceptron and Nu-support vector classifiers. Features are selected based on a Linear Regression based correlation coefficient (LR-CC) score with a different range like n1, n2,n3,n4 a, for d1 used n1 and n2 dataset,for d2 dataset, combined dataset of n3 and n4 are used and developed a new dataset d3 which is the combination of d1 and d2 by using the feature selection strategy which results in 997 features out of 2548 features of the EEG Brainwave dataset with a classification accuracy of emotion recognition 98.75%, which is comparable to many state-of-the-art techniques. It has been established some scientific groundwork for using data fusion strategy in emotion recognition. 2022. International Journal of Advanced Computer Science and Applications. All Rights Reserved. -
Classification of Psychological Disorders by Feature Ranking and Fusion using Gradient Boosting Classification of Psychological Disorders
Negative emotional regulation is a defining element of psychological disorders. Our goal was to create a machine-learning model to classify psychological disorders based on negative emotions. EEG brainwave dataset displaying positive, negative, and neutral emotions. However, negative emotions are responsible for psychological health. In this paper, research focused solely on negative emotional state characteristics for which the divide-and-conquer approach has been applied to the feature extraction process. Features are grouped into four equal subsets and feature selection has been done for each subset by feature ranking approach based on their feature importance determined by the Random Forest-Recursive Feature Elimination with Cross-validation (RF-RFECV) method. After feature ranking, the fusion of the feature subset is employed to obtain a new potential dataset. 10-fold cross-validation is performed with a grid search created using a set of predetermined model parameters that are important to achieving the greatest possible accuracy. Experimental results demonstrated that the proposed model has achieved 97.71% accuracy in predicting psychological disorders 2023, International Journal of Advanced Computer Science and Applications.All Rights Reserved. -
Lipase-Catalyzed Resolution Of 1-[4-(Benzyloxy)phenyl]hex-5-en-3-ol: Synthesis of (-)-Centrolobine /
Asian Journal Of Chemistry, Vol.29, Issue 10, pp.2321-2326, ISSN: 0975-427X (Online) 0970-7077 (Print). -
A catalytic, one-pot and green synthesis of α-amino nitriles : Cu(BF4)2.X H2O an efficient catalyst /
Letters In Organic Chemistry, Vol.14, Issue 6, pp.440 - 445, ISSN: 1570-1786. -
Synthetic approaches toward butenolide-containing natural products
The butenolide scaffold is ubiquitous in many natural products and pharmaceutical active ingredients. These candidates appeal to organic chemists for the synthesis of products with various biological activities. This review delineates the efforts made in the total synthesis of natural products based on the butenolide core unit such as umbelactones, akolactones, ansepcinolide, lissoclinolide, fugomycin, and muricadienin. Many of the reported syntheses involve chiral pool, enzyme resolution, and chiral auxiliary, or enantioselective approaches as a key step. Overall, this review highlights the synthetic methods involved in the preparation of butenolide-containing molecules and aims to increase the profile of such scaffolds to the synthetic community. 2022 Wiley Periodicals LLC. -
Synthetic Applications of Prins Cyclization in Natural Product Syntheses
The natural products having tetrahydropyran unit with multiple chiral centers serve as magnificent building blocks for various active pharmaceutical ingredients (APIs). Prins cyclization is one of the wonderful strategies to construct tetrahydropyran unit stereoselectively in asymmetric synthesis. In this account, we discuss our research efforts toward the synthesis of various natural products from the past two decades (20052020) by using Prins cyclization as a key step. Further, the synthetic utility of this reaction was investigated and well demonstrated on various molecules successfully. 2022 The Chemical Society of Japan & Wiley-VCH GmbH. -
Lipase-catalyzed resolution of 1-[4-(benzyloxy)phenyl]hex-5-en-3-ol: Synthesis of (-)-centrolobine
A practical and efficient method for the preparation of homoallylic alcohol and its successful enzymatic resolution has been developed. This lipase-catalyzed resolution process has been optimized with respect to different lipases and solvents. Moreover, Mitsunobu strategy has been applied to recover the unwanted isomer. Further optically enriched homoallylic alcohol has been employed for the synthesis of (-)-centrolobine. 2017, Chemical Publishing Co. All rights reserved. -
A catalytic, one-pot and green synthesis of a-amino nitriles: Cu(BF4)2.x H2O an efficient catalyst
The Strecker reaction is a first reported multicomponent reaction for the preparation of a-aminonitriles. The a-aminonitriles are important intermediates for various aminoacids, 1,2-diazines, heterocycles and biologically active compounds like Saframycin A and Ecteinascidin 746. The preparation of a-aminonitriles by Strecker approach using MCR attracted many research groups owing atom economy to avoid multistep synthesis and to follow Green chemistry principles. Methods: A-aminonitriles have been synthesized using Strecker reaction by treatment of aldehydes, amines, with TMSCN in the presence of Cu(BF4)2.xH2O as a catalyst in one pot under neat conditions. Various aromatic and aliphatic aldehydes have been studied with different primary and secondary amines. Results: The reaction condition has been optimized by choosing a model reaction under various solvents and found good yields under neat conditions. Moreover, various catalytic amounts of Cu(BF4)2.xH2O has also been studied and found 3 mole% providing better yields. The reaction has been studied with different substrates of aldehydes and amines. Some of the products were characterized by comparison of their spectral data (1H NMR, 13C NMR, IR and MS) and physical properties with those of authentic samples reported in the literature. Conclusion: Afacile and efficient one-pot synthesis of a-amino nitriles at ambient temperature using copper(II)tetrafluoroborate as a novel catalyst under solvent-free conditions via Strecker reaction is reported. The process is simple and environmentally benign using the commercially available and inexpensive catalyst. 2017 Bentham Science Publishers. -
Synthetic Approaches of Prelactone and Its Analogues: A Review
In this review we have discussed the synthetic approaches of prelactones and their epimers from 1997 to date. The presence of unique molecular architecture and its high biological importance enhanced the research activity over the last two decades. Most of the syntheses involve either a chiral auxiliary, chiral pool or catalytic enantioselective approaches as a key step. Overall this review highlights the contribution from different research groups in the total synthesis of various prelactones. 2021 Wiley-VCH GmbH -
Synthetic Approaches to Diospongins: A Two Decade Journey
Tetrahydropyran units having multiple stereogenic centers serve as excellent building blocks for various active pharmaceutical ingredients (APIs). In particular, the presence of the unique molecular architecture of the trisubstituted tetrahydropyran (THP) unit in diospongins enhances their biological activity due to multiple stereogenic centers and has attracted attention from the synthetic community over the last two decades. In this review, we discuss synthetic approaches to chiral and racemic forms of diospongins during the period 2006 2020 in chronological order. 2022 by the authors. -
Desymmetrisation of meso-2,4-Dimethyl-8-oxabicyclo[3.2.1]-oct-6-ene-3-ol and its Application in Natural Product Syntheses
The compounds containing chiral centers and different functional groups serve as magnificent building blocks for the preparation of various natural products that are having immense biological activity. Dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-3-ol is one of the wonderful synthons to construct multiple stereo centers at a time during the asymmetric synthesis. In this account, we discuss our research efforts toward the synthesis of various simple and complex natural products from the past three decades (19952020) by using dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-3-ol as a synthon. Moreover, the synthetic utility of this starting material was investigated and well demonstrated. Further, we executed the desymmetrization of dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-3-ol by hydroboration to get different chiral centers. After obtaining the stereocenters, we could manage either the fragment, formal or total synthesis of natural products, by simple protection and deprotection sequence followed by C?C bond formation steps. 2021 The Chemical Society of Japan & Wiley-VCH GmbH -
A Journey toward the Syntheses of ?-Amino-?-hydroxybutyric Acid (GABOB) and Carnitine
In this review, we discuss the synthetic approaches to ?-amino-?-hydroxybutyric acid (GABOB) and carnitine from 1980 to date. The unique structure and biological importance of these molecules have created much interest in various synthetic approaches over the last four decades by organic chemists from across the world. Most of the syntheses are asymmetric methods that involved chiral pool, enantioselective synthesis, enzyme resolution, or a chiral auxiliary as a source of chirality, and the biological significance of the molecules was also discussed. The compiled synthetic methods may fill the existence gap, simplify the complexity involved in the synthesis, and allow the best synthetic route to be found by comparison of all the methods. However, this review also will be useful to prepare similar kind of scaffolds present in various complex natural products. 2021 American Chemical Society -
A review on synthetic approaches towards kavalactones
Kavalactones are classes of ?-pyrone and 5,6-dihydropyrone derivatives showing various biological activities, and numerous approaches have been reported for the preparation of these molecules. In this review, we discuss the different synthetic approaches towards these naturally occurring lactones, in both racemic and enantiomerically pure forms, that have been reported in the literature to date. It is hoped that this review will assist researchers in the development of additional and efficient synthetic routes towards kavalactones. 1 Introduction 2 Synthetic Approaches for the Preparation of Kavalactones 3 Conclusion. 2021. Thieme. -
Pyrazole Derivative Containing Naphthalene Moiety: Cytotoxocity (Breast and Cervical Cancer), Antibacterial and Antifungal Studies Using Experimental and Theoretical Tools
In the present study, the title compound is named 4-((5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)(6-methoxynaphthalen-1-yl)methyl)-5-methyl-2-phenyl-1,2-dihydropyrazol-3-one was synthesized, and its antibacterial, antifungal, cytotoxic activity was studied by both experimental and in silico methods. The molecular structure was optimized using DFT/B3LYP method with cc-pVDZ as a besis set, and frontier molecular orbital (FMO) studies was used to explain the physiochemical properties of that molecule by the energy of interacting orbitals. NBO describes the intra delocalization of electrons in the molecule, which support the stability of that molecule. Noncovalent interaction (NCI) explains the nonbond interactions present in the molecule. Drug-likeness property of 405 C have been checked by absorption, distribution, metabolism and excretion (ADME) assay, result shown all the drug-likeness properties in red color region, so we have confirmed this molecule as a drug. 405 C undergoes antibiotic activity against P. aeruginosa organism, antifungal activity against B. cinerea and cytotoxicity activity against MCF-7 and HeLa cell when compared to standard drugs. 2022 Taylor & Francis Group, LLC. -
An insight into the superior performance of ZnO@PEG nanocatalyst for the synthesis of 1,4-dihydropyrano[2,3-c]pyrazoles under ultrasound
The investigation presents a straightforward synthesis of fifteen 1,4-dihydropyrano[2,3-c]pyrazoles using ZnO@PEG nanocatalyst in ethanol via Multicomponent approach under the influence of ultrasound. The present methodology successively tolerates a variety of functional groups and offers several advantages such as excellent yields without chromatographic purification, milder reaction conditions, shorter reaction times, and the use of an environmentally benign reusable catalyst. Ecstatically, the reaction was successfully scaled to gram level ascertaining the wider applicability of ZnO@PEG nanoparticles in multicomponent reactions. 2019 Elsevier Ltd. All rights reserved. -
Synthesis of 1, 8-Naphthyridine-3-Carbonitriles under solvent-free conditions using ceric ammonium nitrate
1,8-naphthyridines are synthesized using a four-component, one-pot approach. This method includes the reaction of aromatic aldehyde, malononitrile, 1,6-dimethylpyridin-2(1H)-one, substituted aniline in a solvent-free condition catalyzed by Ceric Ammonium Nitrate (CAN). Contrary to the reported literature, this distinct method houses several promising factors to the same degree as solvent-free reaction conditions, shorter reaction duration, excellent yields, and a straightforward extraction process. 2023 Elsevier Ltd. All rights reserved.