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Structural, Morphological and Optical Properties of MoS2-Based Materials for Photocatalytic Degradation of Organic Dye
Molybdenum disulfide (MoS2) is a transition metal dichalcogenide (TMDCs) having versatile properties and plays a great role in the photodegradation of organic dyes. MoS2 also finds applications in diverse fields such as catalysis, electronics, and nanomedicine transportation. MoS2 can be prepared by using chemical and physical methods such as hydrothermal, solvothermal, and chemical vapour deposition methods. The preparation method employed can produce subtle but significant changes in the morphology. To increase the efficiency of MoS2, it can be combined with different materials to produce composites that improve the photodegradation efficiency of MoS2. The various methods of preparation, the morphology of MoS2, and photodegradation activity of the MoS2-based nanocomposites are briefly discussed in this review. 2022 by the authors. -
Structural, luminescence and NMR studies on Nd3+-doped sodiumcalcium-borate glasses for lasing applications
In this work, Neodymium (Nd3+) -doped borate glasses were synthesised by melt-quenching method and their structural as well as optical properties were analysed through XRD, Raman, NMR, DSC, UVVisible, luminescence and decay studies for the possible application as laser gain medium. DSC and XRD results revealed that the glasses have high transition temperature and are in amorphous nature, respectively. The vibrational characteristics of the host matrices as well as the effect of Nd3+ incorporation were analysed by using Raman spectra, which exhibit majorly borate groups as supported by NMR results. The band gap energy of the glasses decreases with an increase in Nd3+ concentration. Using Judd-Oflet theory the characteristic intensity parameters (??, ? = 2, 4 and 6) were calculated and further used for calculating the various radiative parameters from the emission spectra. The emission cross-section (?em) was estimated as high as 1.15 10?20 cm2 from the FhtbauerLandenburg (FL) equation for the dominant 4F3/2?4I11/2 (1056 nm) transition. The effect of Nd3+ concentration on the lifetime of the 4F3/2 luminescent level was analysed from the decay curve analyses. From which, the corresponding quantum efficiency (?) was estimated and found as high as 54%. The investigated result suggests the prepared glasses can be utilized as gain medium to generate laser at around 1.05 ?m. 2020 Elsevier Ltd and Techna Group S.r.l. -
Structural Relationship between Cognitive Image, Destination Personality and Tourists Motivation
This research work was an extract from a major research on understanding personality and image of destination. This portion of research intended to identify a theoretical model consisting of cognitive destination image, destination personality traits and tourists motivation in destination branding context and to validate it hypothetically. This research was carried out in Coimbatore District an emerging destination in Tamil Nadu, India between 2018 and 2019. Flourishing erratic tourism industrys scenarios and the need for academic research blended as the motive for this for this model-based study. Evidence was found in the literature that tourists belief about the destination, touristsmotivation and perceived destination personality traits were found interrelated. Thus, the theoretical model was found. For validating the proposed model, a questionnaire confirmed through pilot study containing the required study variables was circulated to the tourists who visited the destination for tourism purposes. With the sample size as 448 after screening and eliminating the illegible responses, three stage process of analysis that include Exploratory Factor Analysis, Confirmatory Factor Analysis and Structural Equation Modeling had been performed. The conceptual model was validated and found that there existed the interrelationship between touristsperceived cognitive image, perceived personality traits of the destination and tourists motivation to tour. Marketers of destinations were suggested to use the model for formulating branding and marketing activities. The scope for further research was pointed out on expanding the research model with other destination perspectives considering the outcome as base. Copyright IJHTS. -
Structural modification of electrophilic group substituted phenyldiazenyl derivatives for antitubercular application
In the present work, four electrophilic group substitute phenyldiazenyl derivatives were synthesized using an electrophilic substitution reaction. The physicochemical analysis was carried out using FT-IR, 1H NMR, and HR-MS data. The photophysical studies were carried out using theoretical methods. Density functional theory was employed to illustrate the electronic and optical characteristics of the synthesized compounds. The HOMO-LUMO energies were theoretically computed in different solvents using Gaussian 09W software and results are compared with the experimental values. The molecule PT4 shows highest bandgap of 4.497eV. Further, the global chemical reactivity descriptors were used to determined nature of chemical reactivity. The anti-tubercular activity was evaluated using invitro and molecular docking techniques and results reveal that barbituric acid coupled with phenyldiazenyl displayed excellent anti-tubercular activity compared with the standard Gentamycin. 2024 Indian Chemical Society -
Structural investigation, spectroscopic and energy level studies of Schiff base: 2-[(3?-N-salicylidenephenyl)benzimidazole] using experimental and DFT methods
The Schiff base 2-[(3?-N-salicylidenephenyl)benzimidazole] (Spbzl) was characterized by FT-Raman, 1H NMR, 13C NMR and single crystal X-ray diffraction technique. Crystallographic studies reveal the presence of two water molecules in the asymmetry unit which aid the intermolecular hydrogen bonding with imidazole ring, and the trans-conformation of the azomethine bond. Theoretical computations conducted using density functional theory (DFT) analysis support the experimental facts. Energy levels estimated by DFT studies are in good agreement with the values obtained from cyclic voltammetry technique. Frontier molecular orbital analysis shows that charge transfer has taken place from donor to acceptor moiety, which is also supported by the high hyperpolarizability values in both gaseous and solution phases, indicating high charge transfer capability of the molecule. A comparative theoretical study of Spbzl with derivative 4-((3-(1H-benzimidazol-2-yl)phenylimino)methyl)-3-hydroxybenzoic acid (Pbzlb) having an added anchor group COOH substituted at para position in the acceptor ring has been made. The result shows the feasibility of charge transfer to the semiconductor surface in dye sensitized solar cell (DSSC) applications for Pbzlb. 2017 Elsevier B.V. -
Structural investigation of higher order members of bismuth system superconductors
Structural formation of higher order Bismuth superconducting compounds Bi1.65Pb0.35Sr2Ca4Cu5Oy (2245) phase and Bi1.65Pb0.35Sr2Ca8Cu9Oy(2289) phase were investigated. The samples were synthesized by solid state reaction technique. Morphological and micro-structural features of the synthesized samples were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). The XRD of both the samples revealed the presence of Bismuth - (2212)& (2223) phases of which (2223) phase was found to be the predominant. The average grain size was found to be around 65 nm. Traces of Ca2PbO4 was also noticed when the samples were synthesised at 835 C. Superconducting transition temperature (TC) of the samples measured by self-inductance method, showed a two-step transition, one around 110 K and the other around 90 Kindicating the presence of (2223)&(2212) phases respectively. But the TC value observed for (2212) phase is about 10 K more than the expected value of 80 K. There was no signature of the formation of (2245) or (2289) phases in this synthesis. -
Structural investigation of discrete solvent protonated vanadium and other transition metal complexes of N-[(E)-(3-ethoxy-2-hydroxyphenyl)methylidene]benzohydrazide, synthetic, spectroscopic and cytotoxicity studies
A new ligand 3-ethoxysalicylaldehyde benzoic hydrazone (H2ESB) and its copper(II), nickel(II), cobalt(II), zinc(II), and dioxidovanadium(V) complexes have been synthesized and characterized by elemental analysis, IR, UVVis and EPR studies. Copper(II) complex (2) contains 2,2?-bipyridine as a coligand. Aroyl hydrazone and its copper and vanadium complexes were characterised by single crystal XRD. The vanadium compound crystallized in triclinic space group P1- and copper compound in orthorhombic space group P212121. The solvent molecule DMF protonates to form ammonium ion in vanadium complex which neutralises the charge on the vanadium ion. Both complexes copper and vanadium show distorted square pyramidal geometry. From EPR results, spin Hamiltonian and bonding parameters were calculated. The g values in copper complexes indicate the presence of the unpaired electron in the dx?y orbital. In vitro cytotoxicity studies of aroylhydrazone and its complexes showed that copper, cobalt and vanadium complexes are more cytotoxic than hydrazone and other complexes against Dalton's lymphoma ascites cells (DLA). 2019 Elsevier B.V. -
Structural investigation of Cr2CTx/NiFe2O4 MXene composite as a bifunctional electrocatalyst for water splitting
The electrocatalytic water splitting offers great potential as an environmentally friendly and sustainable method to produce hydrogen and oxygen, the former serving as a renewable alternative to traditional fossil fuels. MXene, a novel two-dimensional (2D) layered class of materials, has gained enormous attention as an electrocatalyst for water splitting. This versatile material can be tailored to enhance its electroactive surface sites and stability toward electrocatalytic performance. Herein, we have designed a 2D hybrid material, Cr2CTx/NiFe2O4, via an in-situ hydrothermal approach. NiFe2O4 spheres decorated on layered-Cr2CTx are subjected to analysis using XRD, FTIR, TGA, XPS, FESEM, HRTEM-SAED, and optical profilometry. The synthesized hybrid MXene material shows outstanding activity for overall water splitting compared to Cr2CTx and NiFe2O4. Cr2CTx/NiFe2O4 exhibits an overpotential of 144 mV and 159 mV at a current density of 10 mA cm?2 for hydrogen evolution and oxygen evolution reactions, respectively, and achieves a cell potential of 1.69 V for overall water splitting. This study reveals valuable insights on bi-functional 2D hybrid MXene materials for electrocatalytic water splitting. 2024 Elsevier B.V. -
Structural Health Monitoring Using Machine Learning Techniques
Environmental factors, particularly vibrations and temperature can damage the structural health of the building. To avoid heavy damage to the building and to maintain the building's structural health this paper suggests monitoring of building using machine learning algorithms. Machine learning algorithms are used to predict temperature and vibration damages in buildings. Temperature and vibration values are obtained through the grove vibration sensor and NTC thermistor attached to Raspberry Pi 3B plus. In the Raspberry pi, Machine learning algorithms are executed. The activation functions used are Relu, Sigmoid, and Tanh. The experimental results reveal that the Sigmoid activation function gives the best results in terms of metrics with accuracy 94.25, Precision 0.951, Recall 0.912, and F1 score 0.388. The sigmoid function is used in machine learning algorithms for predicting temperature and vibrations. Predicted temperature and vibrations damages are sent to the server and viewed through the user mobile. K- Nearest Neighbor algorithm produced best results with an accuracy rate of 85.50, Precision of 0.922, Sensitivity of 0.830, Specificity of 0.840 and F1 score of 0.873. 2023 IEEE. -
Structural health monitoring using AI and ML based multimodal sensors data
Climatic changes, sudden or gradual, influence the structural health of buildings and bridges due to variations in temperature and humidity. Risk and disaster management plays a vital role in the decision-making process for safeguarding structures. Data analytics from sensors systems in smart structures aid in taking appropriate action in securing buildings during natural calamities. The correlation between climate and structural measuring responses can be further improved using artificial intelligence (AI)- machine learning (ML) algorithms to monitor and predict structural health and take any precautionary steps before the event of a casualty. Linear regression is an efficient tool for analyzing structural health. The proposed work's objective is to monitor and predict the structural health and inform the concerned authorities in the event of a failure in advance, using AI-ML approaches. We have analyzed various sensor data sets to predict the health of a structure based on the crack developed. From the data obtained for experimentation, mean width of the crack is observed as 2.38 cm and mean length of the crack is 63.36 cm. 2023 The Authors -
Structural equation based model to investigate the moderating effect of fear of COVID using partial least square method
This study assesses the magnitude of work life integration among health care workers with the help of positive psychology constructs in COVID-19 crisis. The effect of optimistic approach and sense of belongingness is studied on the performance-oriented healthcare workers and how it influenced their withdrawal cognition. The moderating effect of fear of corona disease is also analysed on performance orientor and withdrawal cognition. Empirical data derived through face-to-face interactions of 357 health care professionals using partial least squares-structural equation modelling PLS-SEM 3.3.3 provides the detailed analysis of the model (measurement and structural). The results indicate that optimistic approach and sense of belongingness contribute towards performance-oriented health care work with R2 value of 79% (? =.533; t = 7.042; p< 0.00) and (? =.0.391; t = 5.43; p< 0.00) respectively. Performance orientor show negative relation with withdrawal cognition (? = -0.122.; t = 2.11; p< 0.00) and R2-value of 74.8%. The moderation effect of fear of corona disease shows negative affect on performance orientor (? = -0.044.; t = 26.10; p< 0.01); R2-value of 79.3% and positive interaction on the withdrawal cognition (? = 0.844; t = 38.42; p< 0.00) and R2-value of 76.4%. 2022 Taru Publications. -
Structural engineering on indole derivative for rechargeable organic lithium-ion battery
In the present work, the indole derivative, namely, 3,3?,3?-methane-triyl-tris-1H-indol(tris-Ind), is synthesized and characterized as an organic electrode material in rechargeable lithium-ion batteries (RLIB). The structural characterization of the synthesized molecule is carried out using physicochemical techniques. The ball milling method is used for the lithiation process to form electroactive lithiated tris-Ind (Li-tris-Ind). The electrochemical activity of Li-tris-Ind is measured in aqueous and non-aqueous electrolytic media, and the results are compared. The aqueous cell system delivers an average cell potential of 0.76V with a discharge capacity of 189 mAhg?1, whereas the non-aqueous cell system delivers an average potential of 1V with 506 mAhg?1. The potentiostatic electrochemical impedance spectroscopic studies reveal the kinetics of finite diffusion. The organic electrode shows good cyclic stability and reproducibility in both systems, making it a significant practical material for RLIB applications. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. -
Structural domination and coloring of some (P7,C7)-free graphs
We show that every connected induced subgraph of a graph G is dominated by an induced connected split graph if and only if G is C-free, where C is a set of six graphs which includes P7 and C7, and each containing an induced P5. A similar characterization is shown for the class of graphs which are dominated by an induced connected complete split graph. Motivated by these results, we study structural descriptions of some classes of (P7, C7)-free graphs. In particular, we give structural descriptions for the class of (P7, C7, C4, gem)-free graphs and for the class of (P7, C7, C4, diamond)-free graphs. Using these results, we show that every (P7, C7, C4, gem)-free graph G satisfies ?(G)?2?(G)?1, and that every (P7, C7, C4, diamond)-free graph H satisfies ?(H)?max{3,?(H)}. 2020 Elsevier B.V. -
Structural characterization of paraffin wax soot and carbon black by XRD
From past few decades, an exponential increase in the research related to carbon nanomaterials and their excellent applications has been witnessed. Realizing the need for new potential precursors and cost effective production methods, we have investigated two precursors-paraffin wax soot (CS) and carbon black (CB). Structural and morphological features of the samples are analyzed by various techniques such as X-ray diffraction, high resolution scanning electron microscopy and electron dispersive spectroscopy. The lateral size of the aromatic lamellae, stacking height, the average spacing of the (002) crystallographic planes (d002) and aromaticity are found to be 15.12 44.30 3.57 0.912 and 15.26 43.23 3.68 0.986 respectively for paraffin wax soot and carbon black. Very low ? and ? band intensity ratio shows a low amount of disorder in the samples. SEM micrographs of the samples reveal non-uniform carbon nanospheres of particle sizes 26-94 nm. Asian Journal of Chemistry 2013. -
Structural characterization of graphene layers in various Indian coals by X-Ray Diffraction technique
The results of the structural investigation of three Indian coals showed that, the structural parameters like fa & Lc increased where as interlayer spacing d002 decreased with increase in carbon content, aromaticity and coal rank. These structural parameters change just opposite with increase in volatile matter content. Considering the 'turbostratic' structure for coals, the minimum separation between aromatic lamellae was found to vary between 3.34 to 3.61 A for these coals. As the aromaticity increased, the interlayer spacing decreased an indication of more graphitization of the sample. Volatile matter and carbon content had a strong influence on the aromaticity, interlayer spacing and stacking height on the sample. The average number of carbon atoms per aromatic lamellae and number of layers in the lamellae was found to be 16-21 and 7-8 for all the samples. Published under licence by IOP Publishing Ltd. -
Structural and physico-chemical evaluation of melatonin and its solution-state excited properties, with emphasis on its binding with novel coronavirus proteins
Melatonin is a natural hormone from the pineal gland that regulates the sleep-wake cycle. We examined the structure and physico-chemical properties of melatonin using electronic structure methods and molecular-mechanics tools. Density functional theory (DFT) was used to optimise the ground-state geometry of the molecule from frontier molecular orbitals, which were analysed using the B3LYP functional. As its electrons interacted with electromagnetic radiation, electronic excitations between different energy levels were analysed in detail using time-dependent DFT with CAM-B3LYP orbitals. The results provide a wealth of information about melatonin's electronic properties, which will enable the prediction of its bioactivity. Molecular docking studies predict the biological activity of the molecules against the coronavirus2 protein. Excellent docking scores of ?7.28, ?7.20, and ?7.06 kcal/mol indicate that melatonin can help to defend against the viral load in vulnerable populations. Hence it can be investigated as a candidate drug for the management of COVID. 2020 Elsevier B.V. -
Structural and Optical Properties of Alumino Lead Borate Glasses Containing Copper Oxide
The alumino lead borate glasses with small amounts of copper oxide were synthesized by melting and quenching according to the relation 50B2O3-30PbO-(20x)Al2O3-xCuO with x = 0, 0.10, 0.25, 0.50, 0.75 and 1.00 mol%. The powder XRDs had no sharp peaks which show that the samples are amorphous. Density of the glasses increased as the content of the CuO increased. FTIR spectroscopic studies reveal the presence of BO3, BO4, PbO4, AlO4, pentaborate [B5O8], diborate [B4O72] and dipentaborate B512 structural units. The UV-visible absorption studies showed that the refractive index, indirect energy gap, oxide ion polarizability and optical basicity had composition dependence which were related to the glass structure. As the CuO concentration increased, the refractive index decreased, indirect energy gap increased, oxide ion polarizability decreased and optical basicity decreased. Optical band gap increased with increasing CuO content as the band gap for bridging oxygens is higher than that for non-bridging oxygens. 2024 Indian Ceramic Society. -
Structural and morphological characterization of hydrothermally synthesized N-Carbon Dot @ Fe3O4 composites for heavy metal ion detection
Heavy Metal-ion contamination is one of the most serious issues facing day-to-day life. To address this issue, sensing and removal of heavy metal ions in contaminated water become indispensable. Carbon Dots are hydrophilic in nature with magnificent electron acceptor and electron donator and hence it has been used as fluorescent probes for sensing applications. The present study deals with the synthesis of N-Carbon Dot (N-CD) @ Fe3O4 composite which was successfully fabricated via the hydrothermal method. The surface structure and morphology of the synthesized composite were characterized using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The elemental analysis of a sample was characterized using Energy Dispersive Spectroscopy (EDS). Further, the phase occurrence and the molecular vibration were analysed using XRD and Fourier Transform Infra-Red Spectroscopy (FTIR). Finally, the optical studies were measured using Ultravioletvisible Spectroscopy (UV Vis) and Photoluminescence Spectroscopy (PL). The prepared composite exhibited noticeable fluorescence properties and has promising potential for the detection and removal of toxic heavy metal ions in water. 2022 -
Structural and functional characterization of a hypothetical protein in the RD7 region in clinical isolates of Mycobacterium tuberculosis an in silico approach to candidate vaccines
Background: Mycobacterium tuberculosis has been ravaging humans by inflicting respiratory tuberculosis since centuries. Bacillus Calmette Guerine (BCG) is the only vaccine available for tuberculosis, and it is known to be poorly effective against adult tuberculosis. Proteins belonging to the ESAT-6 family and PE/PPE family show immune responses and are included in different vaccine trials. Herein, we study the functional and structural characterization of a 248 amino acid long putative protein novel hypothetical protein 1 (NHP1) present in the RD7 region of Mycobacterium tuberculosis (identified first by subtractive hybridization in the clinical isolate RGTB123) using bioinformatics tools. Results: Physicochemical properties were studied using Expasy ProtParam and SMS software. We predicted different B-cell and T-cell epitopes by using the immune epitope database (IEDB) and also tested antigenicity, immunogenicity, and allergenicity. Secondary structure of the protein predicted 30% alpha helices, 20% beta strands, and 48% random coils. Tertiary structure of the protein was predicted using the Robetta server using the Mycobacterium smegmatis protein as the putative protein with homology. Structural evaluations were done with Ramachandran plot analysis, ProSA-web, and VERIFY3D, and with GalaxyWEB server, a more stable structure was validated with good stereo chemical properties. Conclusion: The present study of a subtracted genomic locus using various bioinformatics tools indicated good immunological properties of the putative mycobacterial protein, NHP1. Evidence obtained from the analyses of NHP1 using structure prediction tools strongly point to the fact that NHP1 is an ancient protein having flavodoxin folding structure with ATP binding sites. Positive scores were obtained for antigenicity, immunogenicity, and virulence too, implying the possibility of NHP1 to be a potential vaccine candidate. Such computational studies might give clues for developing newer vaccines for tuberculosis, which is the need of the hour. 2022, The Author(s). -
Structural and antibacterial assessment of two distinct dihydroxy biphenyls encapsulated with ?-cyclodextrin supramolecular complex
?-Cyclodextrin plays a vital role in biological application because it can enhance the stability and solubility of the guest molecules in the supramolecular inclusion complexes. Moreover, the ?-Cyclodextrin inclusion complex has control-releasing behavior and lower toxicity than bare guest molecules. To improve the solubility and stability properties of two structurally different fluorescent guest molecules, namely 2,2?-dihydroxy biphenyl and 3,3?-dihydroxy biphenyls, they involve the ?-Cyclodextrin inclusion complex process. Optical measurements clearly described the efficient binding through the changes in the absorbance and emission intensities of guest molecules in the presence of ?-Cyclodextrin. The Job's plot from absorbance measurements reveals the 1:1 stochiometric ratio of binding of guests and the ?-Cyclodextrin host. The FT-IR spectra of the solid complex show the characteristic stretching and bending vibrations from both the guests and the host molecule. The 1HNMR spectra of the inclusion complex promote downfield shifting of guest molecule protons upon binding with the ?-Cyclodextrin host. The solid complex prepared using the solution method exhibits superior antibacterial activity against both gram-positive and gram-negative bacteria compared to the kneading and physical mixing methods. 2024