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Morphology of interstellar medium using multi-wavelength obervations
The interstellar medium (ISM) is the matter that exists between the stars in a galactic system. The structure and composition of a galaxy can be understood by a study of the ISM. Our Galaxy is the only place where the observations of the ISM can be resolved and studied in great detail. There are various archived observations from space-based and ground based telescopes spanning a large region of the electromagnetic spectrum. Combining these different observations with one another will help to study the ISM on a large scale. We have compiled some such observations and analyzed the column density data, to study the ISM and make the database available to the scientific community for further investigations. The data was taken from papers published over a span of 60 years (1951 to 2010). The column densities in these papers were derived using different methods and observations from various telescopes operating in different wavelengths. We compiled these diverse data into a single catalogue and analysed the data. We studied the correlations between the line of sight gas and dust and reported new correlations not published before (APJS, 119(1), 8, 2012). We also studied the spatial distribution of the interstellar gas and dust and have estimated the corresponding exponential vertical scale heights. There also exists a wide range of photometric data from various telescopes which can be combined to cover a large range of wavelengths. We have made use of Galaxy Evolution Explorer (GALEX) photometric data in conjunction with Sloan Digital Sky Survey (SDSS) data to obtain the point sources observed by both missions. GALEX observed in two bands simultaneously, the far-ultraviolet (FUV: 1350 1750 and the near-ultraviolet (NUV: 1750 - 2750 , while SDSS observed in five bands u, g, r, i and z, with effective wavelengths ranging from 3551 to 8931 GALEX and SDSS together provide photometric data ranging from the far-ultraviolet to the near-infrared. -
Morphological Characterization of Selected Aliphatic and Aromatic Hydrocarbons.
In the last few years considerable interest has been aroused in the study of amorphous carbon. Amorphous carbon has a wide range of properties that are primarily controlled by the different bond hybridizations possible in such materials. This gives different properties like high strength, flexibility etc. Due to these properties, they are used in thin film technology and in nanoscale electronic devices. Films can range from those with high transparency and are hard and diamond-like, through to those which are opaque, soft and graphitic-like. Application areas include field emission cathodes, electronic devices, medical and optical coatings. Hence study of different carbon structures has been of great interest for many researchers. Several techniques have been used to study various sources of carbon. Hydrocarbons are the most abundant sources of carbon. The majority of hydrocarbons found, naturally occur in crude oil and the decomposition of these give hydrogen and carbon. Incomplete combustion of hydrocarbons leads to the production of polycyclic aromatic hydrocarbons. Hydrocarbon combustion therefore mainly have aromatic and aliphatic chains of carbon. Hydrocarbons are by far the most widespread precursors among carbon sources employed in the production of carbon nanotubes and carbon nanosphers. In the present study diesel soot, camphor soot and coal has been used as precursors for nanomaterials. Impurities in the samples can reduce efficiency of production. Mineral matter encompasses dissolved salts in the pore water and inorganic elements associated with the organic compounds, as well as crystalline and non-crystalline mineral particles. Quantitative analysis of minerals and other inorganics contributes to defining coal quality. Therefore a study on effects of bio and base leaching on coal samples are also done. XRD is one of the majorly used techniques to deduct the various structural parameters like interlayer spacing of crystalline (d002) structure, crystallites size (La, Lc), aromaticity (fa), number of layers of carbon atoms per aromatic lamellae(n). According to Scherrer, crystallite size varies inversely with peak width. Therefore it is a known fact that a broad hump in the spectrum indicates the presence of nano layers. These parameters are determined from the intensity profiles of the sample hydrocarbons. Also the structure of the hydrocarbon can be characterized using NMR and SEM EDS. 1H NMR spectra can yield structural information that allows classification of complex mixtures containing hundreds of aromatic, naphthenic, paraffinic, olefinic, and isoparaffinic compounds. SEM/EDS techniques allow both inorganic analysis of bulk materials and determination of chemistry and abundance of microscopic constituents. SEM analysis also gives us the size of nano particles formed in the sample. EDS allows one to identify what those particular elements are and their relative proportions. CHNS analysis gives the elemental composition of the samples. The study shows that the carbonaceous soot produced from combustion of diesel in engine show the presence of significant amount of carbon nanomaterials. The SEM micrographs indicate that nanoparticle present in diesel soot is clusters of carbon nanospheres. EDS analysis reveals the soot particles to be composed of primarily carbon and oxygen along with hydrogen. NMR spectrum of the soot reveals significant aliphatic component with predominance of methyl and methylene groups on ?and ?? positions to aromatic rings. Camphor soot XRD analysis shows presence of ordered layers of nanolayers and laso the presence of CNTs. The SEM micrographs of camphor show the presence of carbon nanostructures. The EDS analysis shows more of carbon and oxygen along with aluminium, silicon and potassium. Study of coal samples treated with biological leaching agents reveals that Penicillium spp (PE) treated sample is having more of a graphitic or ordered structure and the d002 spacing of this sample is 3.37 ?? which is close to graphite. XRD data of coal sample treated with base leaching agents confirms the turbostratic structure of coal. The SEM micrographs of the samples show that KN has more graphite like sheet structures. -
Morphological and Elemental Investigations on CoFeBO Thin Films Deposited by Pulsed Laser Deposition for Alkaline Water Oxidation: Charge Exchange Efficiency as the Prevailing Factor in Comparison with the Adsorption Process
Abstract: Mixed transition-metals oxide electrocatalysts have shown huge potential for electrochemical water oxidation due to their earth abundance, low cost and excellent electrocatalytic activity. Here we present CoFeBO coatings as oxygen evolution catalyst synthesized by Pulsed Laser Deposition (PLD) which provided flexibility to investigate the effect of morphology and structural transformation on the catalytic activity. As an unusual behaviour, nanomorphology of 3D-urchin-like particles assembled with crystallized CoFe2O4 nanowires, acquiring high surface area, displayed inferior performance as compared to coreshell particles with partially crystalline shell containing boron. The best electrochemical activity towards water oxidation in alkaline medium with an overpotential of 315 mV at 10 mA/cm2 along with a Tafel slope of 31.5 mV/dec was recorded with coreshell particle morphology. Systematic comparison with control samples highlighted the role of all the elements, with Co being the active element, boron prevents the complete oxidation of Co to form Co3+ active species (CoOOH), while Fe assists in reducing Co3+ to Co2+ so that these species are regenerated in the successive cycles. Thorough observation of results also indicates that the activity of the active sites play a dominating role in determining the performance of the electrocatalyst over the number of adsorption sites. The synthesized CoFeBO coatings displayed good stability and recyclability thereby showcasing potential for industrial applications. Graphic Abstract: [Figure not available: see fulltext.] 2021, The Author(s). -
More insights into bar quenching: Multi-wavelength analysis of four barred galaxies
The underlying nature of the process of star formation quenching in the central regions of barred disc galaxies that is due to the action of stellar bar is not fully understood. We present a multi-wavelength study of four barred galaxies using the archival data from optical, ultraviolet, infrared, CO, and HI imaging data on star formation progression and stellar and gas distribution to better understand the process of bar quenching. We found that for three galaxies, the region between the nuclear or central sub-kiloparsec region and the end of the bar (bar region) is devoid of neutral and molecular hydrogen. While the detected neutral hydrogen is very negligible, we note that molecular hydrogen is present abundantly in the nuclear or central sub-kiloparsec regions of all four galaxies. The bar co-rotation radius is also devoid of recent star formation for three out of four galaxies. One galaxy shows significant molecular hydrogen along the bar, which might mean that the gas is still being funnelled to the centre by the action of the stellar bar. Significant star formation is also present along the bar co-rotation radius of this galaxy. The study presented here supports a scenario in which gas redistribution as a result of the action of stellar bar clears the bar region of fuel for further star formation and eventually leads to star formation quenching in the bar region. 2020 ESO. -
Moral Identity, Moral Emotions and Maladaptive Personality Traits Among Adolescents in South Korea by Doo Jong Kim
The rule of survival of the fittest often thwarted the leap towards holistic development. How does morality associate with personality in adolescent development? Drawing on the theories of Augusto Blasi and Gordon Allport, the present study took a morality-personality integrative approach to adolescent development and viewed moral identity centrality as an agentic drive for their holistic growth. It aimed to determine whether moral identity centrality, other-praising moral emotion, and personality dysfunction of maladaptive personality traits are coherent in predicting antisocial behaviour in a sample of 436 Korean adolescents (M = 15.71 years, SD = .70; female 48.4%). The present study set up three hypotheses in the structural relationship of research variables (i.e., moral identity centrality, other-praising moral emotion, personality dysfunction of maladaptive personality traits and antisocial behaviour). Hypothesis 1: Personality dysfunction of multiple maladaptive personality traits predicts antisocial behaviour. Hypothesis 2: Other-praising moral emotion and personality dysfunction mediate moral identity centrality and antisocial behaviour. Hypothesis 3: Sex does not make notable differences in the structural relationship of research variables. The study analyzed the data mainly through structural equation modelling (SEM). As a result, all hypotheses were accepted. First, four multiple maladaptive traits, i.e., negative affectivity, antagonism, disinhibition, and psychoticism, significantly predicted adolescents antisocial behaviour (and#946; = .791, p lt .001) (Hypothesis 1). Second, the modified structural model showed a serial multiple mediation effect of other-praising moral emotion and personality dysfunction between moral identity centrality and antisocial behaviour (Hypothesis 2). Third, multi-group analyses showed apparent coherence among research variables regardless of sex (Hypothesis 3). -
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MOOCs: A disruptive teaching-learning process in interdisciplinary boundaries /
International Journal of Language & linguistics, Vol.1, Issue 2, pp.54-61, ISSN No: 2374-8869. -
Monopsonistic exploitation in contract farming: Articulating a strategy for grower cooperation
Contract farming has been considered a new hope to instil dynamism in third world agriculture. However, there remains serious concern whether small peasants will be able to benefit from this system since buyers may often be a single large or at most, few large corporations, a typical case of monopsony. In this paper we question the basis of the fears that are often raised in the literature. A clear analytical approach to understanding the (economic) meaning of monopsony helps us articulate a strategy for grower cooperation that could effectively deal with monopsony power in contract farming systems. Copyright 2007 John Wiley & Sons, Ltd. -
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. -
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. -
Monitoring nyiragongo volcano using a federated cloud-based wireless sensor network
Current Nyiragongo Volcano observatory systems yield poor monitoring quality due to unpredictable dynamics of volcanic activities and limited sensing capability of existing sensors (seismometers, acoustic microphones, GPS, tilt-meter, optical thermal, and gas flux). The sensor node has limited processing capacity and memory. So if some tasks from the sensor nodes can be uploaded to the server of cloud computing then the battery life of the sensor nodes can be extended. The cloud computing can be used both for processing of aggregate query and storage of data. The two principal merits of this paper are the clear demonstration that the Cloud Computing model is a good fit with the dynamic computational requirements of Nyiragongo volcano monitoring and the novel optimization algorithm for seismic data routing. The proposed new model has been evaluated using Arduino-Atmega328 as hardware platform, Eucalyptus/Open Stack with Orchestra-Juju for Private Sensor Cloud connected to some famous public clouds such as Amazon EC2, ThingSpeak, SensorCloud and Pachube. 2017 IEEE. -
Monitoring and Controlling Data Through the Internet of Things (IOT) System: A Framework to Measure the Public Health
Associating and sharing information by means of the web between actual things, or 'things,' coordinated with sensors, programming, and different advances are known as the Internet of Things (IoT). In order to improve technology through IoT, there have been a number of important studies and investigations. This study exhibits how the Internet of Things might be utilized to screen wellbeing. In this research work, with the help of IoT based human wellbeing checking framework the information circulatory strain, beat rate, internal heat level, pulse, and other crucial signs are providing to the internet. The use of IoT for the human health monitoring system in later on future, need a very accurate assessment of risk and this is required to provide a long term information to the device. 2022 IEEE. -
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. -
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. -
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. -
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 Nanomaterials for the Electrochemical Sensing of Environmental Pollutants
ntegrating molecularly imprinted nanoparticles, environmental contaminants are detected electrochemically on a glassy carbon electrode that caters as the transducer host. The modification of electrodes using different noble nanoparticles resulted in enhanced electrooxidation of analytes. The allocation of chitosan as a reducing and stabilizing agent in the green synthesis of noble metal nanoparticles enhances the sensor's efficiency. Different characterizations like UV-Visible Spectroscopy, Fourier Transform Infra Red Spectroscopy, Transmission Electron Microscopy, and Dynamic Light Scattering analysis further confirm the synthesized nanoparticles' morphology, stability, and size. The different experimental conditions needed for effective detection, like electrolytes, potential window, scan rate, and pH, were optimized with utmost careful examination. The morphological characterization of the electrodes were executed utilizing Scanning Electron Microscopy and Optical profilometry, whereas the electrochemical characterization was performed using Electrochemical Impedance Spectroscopy. The Nyquist plot showcased the low resistance and high charge transfer of modified imprinted electrodes with enhanced surface area. Using Differential Pulse Voltammetry, the sensor was validated with nano to femto-level detection limits and a wide linear range with good sensitivity. The imprinting factor displays the superior electroactivity of imprinted sensors compared to non-imprinted sensors. The molecularly imprinted electrode effectively detected environmental pollutants in different water samples. Hence, all the works point to the exceptional approach of imprinted nanomaterials in electrochemical detection with its simplicity and facile preparation. It may be used to develop a susceptible voltammetric sensor for researching environmental pollutants. -
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 conducting polymer based electrochemical sensor for 4-hexylresorcinal in shrimps /
"Patent Number: 202141044123, Applicant: George Ashlay.
The invention discloses the fabrication of an electrochemical sensor using a molecularly imprinted conducting polymer, which is an extraordinarily proficient and practical electrochemical sensor for quantitative detection of 4-hexylresorcinol (4-HR) in shrimps. 2-aminothiazole (AT) was electropolymerized on the surface of a carbon fibre paper electrode (CFP) in the presence of 4-HR imprinted polymer sheets. To provide precise imprinting sites and control the release of 4-hexylresorcinol templates, bulk-electrolysis was employed. -
Molecular simulations to investigate the guest-induced flexibility of Pu-UiO-66 MOF
Actinide metal-organic frameworks are highly popular because of their significant coordination benefits. Due to production and characterisation challenges, An-MOFs are a relatively less explored coordination polymer. In this study, we considered the experimentally synthesised Pu-UiO-66 MOF, which was the first reported plutonium MOF. In most MOF studies, the framework has been maintained rigid, however, in this case, we investigate both rigid and flexible frameworks. To gain a better understanding of the framework's flexibility, flexible Grand Canonical Monte Carlo (GCMC) simulations were conducted and the calculated results were compared with that of rigid frameworks. Molecular Dynamics (MD) simulations were carried out to examine the effects of framework flexibility of Pu-UiO-66 MOF, a force field-built Grand Canonical Monte Carlo (GCMC) on adsorption of guest molecules, and to analyse the self-diffusion coefficients of acidic gases such as CO2, SO2, and NO2 in the framework. The adsorption isotherms and radial distribution functions for both rigid and flexible frameworks in the presence of gas molecules were compared and analysed using GCMC simulation. Similarly, molecular dynamics simulations including guest molecules were carried out. Following that, the GCMC and MD results were compared and analysed to determine the flexibility of the system. Diffusion studies were conducted at various temperatures and the coefficient of self-diffusion of each gas was examined. In addition, structural analyses, such as angle analysis, were carried out to explore the local changes, such as tilting, observed in the organic ligand derivative. It was also shown that the UFF force field is suitable for Pu-UiO-66. 2022