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Estimation of Ground-State and Singlet Excited-State Dipole Moments of Substituted Schiff Bases Containing Oxazolidin-2-one Moiety through Solvatochromic Methods
Absorption and fluorescence studies on novel Schiff bases (E)-4-(4-(4-nitro benzylideneamino)benzyl)oxazolidin-2-one (NBOA) and (E)-4-(4-(4-chlorobenzylidene amino)benzyl)oxazolidin-2-one (CBOA) were recorded in a series of twelve solvents upon increasing polarity at room temperature. Large Stokes shift indicates bathochromic fluorescence band for both the molecules. The photoluminescence properties of Schiff bases containing electron withdrawing and donating substituents were analyzed. Intramolecular charge transfer behavior can be studied based on the influence of different substituents in Schiff bases. Changes in position and intensity of absorption and fluorescence spectra are responsible for the stabilization of singlet excited-states of Schiff base molecules with different substituents, in polar solvents. This is attributed to the Intramolecular charge transfer (ICT) mechanism. In case of electron donating (?Cl) substituent, ICT contributes largely to positive solvatochromism when compared to electron withdrawing (?NO2) substituent. Ground-state and singlet excited-state dipole moments of NBOA and CBOA were calculated experimentally using solvent polarity function approaches given by LippertMataga, Bakhshiev, Kawskii-Chamma-Viallet and Reichardt. Due to considerable ?- electron density redistribution, singlet excited-state dipole moment was found to be greater than ground-state dipole moment. Ground-state dipole moment value which was determined by quantum chemical method was used to estimate excited-state dipole moment using solvatochromic correlations. Kamlet-Abboud-Taft and Catalan multiple linear regression approaches were used to study non-specific solute-solvent interaction and hydrogen bonding interactions in detail. Optimized geometry and HOMO-LUMO energies of NBOA and CBOA have been determined by DFT and TD-DFT/PCM (B3LYP/6-311G (d, p)). Mulliken charges and molecular electrostatic potential have also been evaluated from DFT calculations. 2016, Springer Science+Business Media New York. -
Probing the nature of defects of graphene like nano-carbon from amorphous materials by raman spectroscopy
Raman spectral characterization of selected carbonaceous materials has been carried out at excitation wavelengths 514, 633 and 1064 nm. Raman studies exhibit the presence of G band owing to the first order of E2g mode scattering. sp3 domains at about 1355 cm-1 (D band) are ascribed to the disordered structures due to the on-site and hoping defects which introduces distortions in the crystal lattice. Spectral de-convolution indicates the prominence of bands namely G, D1, D2, D3 and D4. D3 and D4 bands follow Gaussian, while the others Lorentian distribution. With change in excitation wavelength of laser, the degree of dispersion of G peak and ID/IG intensity ratio are found to increase. The crystallite size La, shows an inverse relation with intensity of defect to graphite band (ID/IG) and it also obeys Tuinstra-Koenig relation for nano-crystalline substance. The lateral size of aromatic lamellae determined using XRD analysis is in good agreement with that of Raman analysis. The feasibility of using kerosene soot, diesel soot and carbon black for electrochemical applications are also explored. -
Radiated flow of chemically reacting nanoliquid with an induced magnetic field across a permeable vertical plate
Impact of induced magnetic field over a flat porous plate by utilizing incompressible water-copper nanoliquid is examined analytically. Flow is supposed to be laminar, steady and two-dimensional. The plate is subjected to a regular free stream velocity as well as suction velocity. Flow formulation is developed by considering MaxwellGarnetts (MG) and Brinkman models of nanoliquid. Impacts of thermal radiation, viscous dissipation, temperature dependent heat source/sink and first order chemical reaction are also retained. The subjected non-linear problems are non-dimensionalized and analytic solutions are presented via series expansion method. The graphs are plotted to analyze the influence of pertinent parameters on flow, magnetism, heat and mass transfer fields as well as friction factor, current density, Nusselt and Sherwood numbers. It is found that friction factor at the plate is more for larger magnetic Prandtl number. Also the rate of heat transfer decayed with increasing nanoparticles volume fraction and the strength of magnetism. 2017 The Authors -
Total k-rainbow domination in graphs
In the modem world a huge concern among people is about their security\ People in the planning and execution focus much about proper security. This is a paper on the Mathematical aspects of some type of security enhancement. If a system is have various nodes and if there is availability of multiple types of security instruments, how will we ensure that every security is used to secure every node in an optimal way? We answer this question here by defining a graph theoretic model named Total k-Rainbow Domination. Here k stands for k types of security instruments. Easiest case is that of k types of cops. We define the optimal value as total k-rainbow domination number. Total k-rainbow domination numbers of certain graphs are calculated. IAEME Publication. -
A concise and effectual method for neutral pitch identification in stuttered speech
Researchers have studied that human-computer interactions (HCIs) can be more effective only when machines understand the emotions conveyed in speech. Speech emotion recognition has seen growing interest in research due to its usefulness in different applications. Building a neutral speech model becomes an important and challenging task as it can help in identifying different emotions from stuttered speech. This paper suggests two different approaches for identifying neutral pitch from stuttered speech. The implementation has proved through its accuracy the best model that can be adopted for neutral speech pitch identification. 2017 Walter de Gruyter GmbH, Berlin/Boston. -
Consumption of antibiotics as self-medication from over-the-counter purchase: An empirical study
Objective: The primary objective of this study is to find the reasons behind the practice of self-medication (SM) by the people with over-the-counter (OTC) drugs which are usually available in all medical stores. Methods: This article presents an empirical view of SM practice with OTC drugs. The research design of the study is descriptive, and the population of the study is customers who buy OTC drugs. The target population of this research is the common public who are all having the possibility to consume OTC drugs ever. The sampling technique used for this study is a systematic random sampling, and the sample size is 144. An instrument used for collecting data is a self-administered questionnaire and personal interview with the pharmacists. The data were analyzed using descriptive statistics. Results: The study results that most of the OTC customers consider SM is not a good practice, even though they practice SM of antibiotics in certain circumstances, due to reasons such as time-saving, convenience, cost saving, avoid waiting time to consult a doctor, easy and quick availability of antibiotics in neighbourhood drug stores, etc. Conclusion: The study concludes the reasons behind the SM practice and some remedies to overcome OTC drug-related problems from SM. 2017 The Authors. Published by Innovare Academic Sciences Pvt Ltd. -
Synthesis of nano-crystalline tin dioxide and its effect on calcination
Nitrate-citrate gel-combustion method was used in this study to prepare nano-crystalline tin dioxide. The samples were calcined at a temperature range of 543-1173 K. The prepared powder was characterized by SEM, TEM and X-ray diffraction. On increasing the temperature with limited supply of air (calcination), there is a systematic increase in tin content accompanied by a reduction in oxygen. The tetragonal nano tin structure formed during the process has about 20 nm in lateral size. With increase in calcination temperature, the carbon content systematically decreased. 2017, Chemical Publishing Co. All rights reserved. -
Grain-growth engineering and mechanical properties of physical-vapour-deposited InSe platelets
The present work demonstrates a novel use of physical vapour deposition for grain-growth engineering by optimizing supersaturation, which led to the evolution of stoichiometric indium monoselenide crystals, employing a custom-fabricated dual-zone furnace. The growth zone was kept at a constant temperature for different experimental runs (673-883K), while the source zone was kept at a stable temperature of 1123K. In this way, the temperature difference ?T = 240-450K resulted in a significant increase of the mass transport between the zones so as to accomplish bulk crystallization. At comparatively low supersaturation (?T = 240K), the presence of nodules and flakes was observed. When ?T = 250K, multiple grains were formed owing to temperature asymmetry at the rough vapour-solid interface. A further increase in supersaturation (?T = 330K) facilitated polyhedral grain growth, with distinct grain boundaries. A subsequent increment in ?T (400K) led to evolution of the polycrystalline morphology to well developed hexagonal platelets owing to adsorption of atoms on surface steps and kinks in accordance with the leading-edge growth mechanism. Energy-dispersive analysis by X-rays and X-ray diffraction experiments were carried out to confirm the structure and phase of crystals. Microindentation studies were done to assess the hardness and mechanical stability of the as-grown crystals in response to external loads in order to explore their suitability for solar cell applications. The investigations of bulk vapour phase transport, morphology and strengthening of InSe platelets provide pathways for the production of crystalline textures with versatile properties. International Union of Crystallography 2017. -
Mediation of Perceived Innovation Characteristics on ERP Adoption in Industrial Cluster
An industrial cluster, due to its close network of institutions, will experience various pressures that force the industry to have a homogeneous structure, norms, and practices. These pressures can also lead to adoption of innovative technologies. Enterprise Resource Planning (ERP) is perceived as a sophisticated technology and diffuses across the cluster by its innovative characteristics. However, firms in the industrial cluster will have different rate of adoption of technologies due to the varying level of knowledge spillover and a heterogeneous absorptive capacity. This study empirically tests how absorptive capacity mediates the institutional forces and the perceived innovation characteristics towards the ERP adoption in an industrial cluster. Mediation effect and the model validity are tested using SEM technique. The results show that absorptive capacity complements the forces of institutional pressure and the perceived innovation characteristics on ERP adoption. The implications of managing the absorptive capacity for better ERP adoption are discussed. 2016 World Scientific Publishing Company. -
Sublimation process and physical properties of vapor grown ?-In2Se3 platelet crystals
Indium selenide (?-In2Se3) crystals have been grown by the closed tube sublimation process in the absence of seed crystals and chemical transporting agents. The composition, structure and morphology of the samples grown under different vacuum conditions were examined by energy dispersive analysis, X-ray diffraction, and scanning electron microscope. Structural features of the crystals obtained in a vacuum of 10?3 mbar exhibited a few reflections not belonging to ? phase, whereas X-ray diffraction spectra of the crystals deposited under a vacuum of 10?6 mbar revealed evidence of sharp peaks with high intensities of ?-In2Se3 crystalline phase. When growth runs were performed for 72 h, voids were observed on the surface whereas for a duration of 120 h, platelet crystals were obtained. Optical properties of these samples were investigated using the FT-IR and photoluminescence spectroscopy. The average transmittance of the platelets in the visible and near infrared region of solar spectrum was found to be ?81% and an optical band gap of ?2.05 eV was computed from the transmission spectrum. Photoluminescence spectra of the grown In2Se3 crystals recorded at room temperature using an excitation laser of wavelength 355 nm showed a peak in the near band edge emission (NBE) corresponding to an energy of 2.01 eV. Under an illumination power of 12 mW/cm2, the photocurrent increased linearly with applied voltage and the dark current was found to be ~2.50?9 A for 10 V. These results suggest that the as-grown ?-In2Se3 platelets crystallized from vapor deposition, possess superior optoelectronic properties than the other phases for solar cell applications. 2016 Elsevier B.V. -
Nonlinear 3D flow of Casson-Carreau fluids with homogeneousheterogeneous reactions: A comparative study
Nonlinear convective flow of magneto-Carreau-Casson liquids past a deformable surface under the aspects of heterogeneous and homogeneous reactions is investigated. The present phenomenon also included the interaction of nonlinear radiation, Ohmic and Joule dissipations. At moderate to high temperature, the nonlinear convection and radiation are significant. The governed nonlinear system is illustrated numerically via Runge-Kutta based shooting scheme in the domain [0,?). Role of significant parameters on flow fields as well as on the fiction factor, heat and mass transportation rates are determined and discussed in depth. Comparison is done for distinct flow fields of Carreau and Casson fluids. It is evaluated that the velocities of Casson liquid are higher in comparison to Carreau fluid model. However, liquid temperature for Casson fluid model is weaker in comparison to Carreau fluid. 2017 -
Synthesis, characterization and photophysical studies of a novel schiff base bearing 1, 2, 4-Triazole scaffold
A novel Schiff base derivative containing 1, 2, 4-triazole nucleus (TMPIMP) was synthesized from 4- [1,2,4] triazol-1-ylmethyl-phenylamine and salicylaldehyde in the presence of glacial acetic acid in an ethanolic medium. The synthesized compound was characterized by 1H-NMR, IR and UV spectral analysis. The excitation and emission spectra of triazolyl methyl phenyl imino methyl phenol (abbreviated as TMPIMP) were recorded in various solvents to investigate their solvatochromic behaviour. Dipole moments of the two electronic states of TMPIMP were calculated from solvatochromic spectral shifts. These were correlated with refractive index (?) and dielectric constant (?) of various solvents. Theoretical calculations were performed to estimate the excited state dipole moment on the basis of different solvent correlation methods, like the Bilot-Kawski, Bakhshiev, Lippert-Mataga, Kawski-Chamma-Viallet and Reichardt methods. The dipole moment in the excited state was found to be higher than that in the ground state due to a substantial redistribution of electron densities and charges. Using a multiple regression analysis, the solvent-solute interactions were determined by means of Kamlet Taft parameters (?, ?, ??). Computational studies were performed by Gaussian 09 W software using a time-dependent density functional theory (TD-DFT) in order to calculate the atomic charges and frontier molecular orbital energies in the solvent phase. The calculations indicated that the dipole moment of the molecule in an excited state is much higher than that in a ground state. The chemical stability of TMPIMP was determined by means of chemical hardness (?) using HOMO-LUMO energies. The reactive centers in the molecule were also identified by molecular electrostatic potential (MESP) 3D plots as a result of TD-DFT computational analysis. 2016 Elsevier B.V. All rights reserved. -
Fear estimation-evidence from BRICS and UK
The paper aims to build a composite Fear Index for the BRICS countries and UK by adding new dimensions to the initial structure, such as overbought/oversold conditions and commodity impacts. The main purpose is to identify the degree in which fear really percolates down to all the market participants, respectively if this generates a certain asset transfer to Gold. The results point out the GMM model as the best fit for explaining the link between the Fear Index and the behaviour of market participants. It also confirms the transfer of assets to a safer asset class during the phases of high volatility on the market. Serials Publications Pvt. Ltd. -
Synthesis, crystal structure and photophysical properties of (E)-4-(4-(2-hydroxybenzylideneamino)benzyl)oxazolidin-2-one
A new Schiff base, (4-(benzylideneamino)benzyl)oxazolidin-2-one has been synthesised from 4-(4-aminobenzyl)oxazolidin-2-one and salicylaldehyde by a simple condensation reaction. Single-crystal X-ray analysis of (E)-4-(4-(2-hydroxybenzylideneamino) benzyl)oxazolidin-2-one (HBOA) revealed that there is a 1-D, slipped, face-to-face motif with off-set, head-to-tail stacked columns. Detailed studies on photophysical properties of the synthesised compound in solutions indicate their potential applications in the field of organic light emitting devices and nonlinear optical materials. Absorption and fluorescence study of HBOA has been conducted in a series of solvents with increasing polarity at room temperature. Ground and excited state dipole moments have been determined experimentally by using LippertMataga polarity function, Bakhshiev solvent polarity parameter, KawskiiChammaViallet solvent polarity parameter and Richardt?s microscopic solvent polarity parameter. Due to the considerable ?-electron density redistribution, the excited state dipole moment was found to be larger than that of the ground state. The ground state dipole moment value was determined by quantum chemical method which was used to estimate excited state dipole moment through solvatochromic correlations. KamletTaft and Catalan methods were used to get the information of both non-specific solutesolvent interactions and hydrogen bonding interactions. TD-DFT (B3LYP/6-311G(d,p)) has been used for the determination of HOMOLUMO energies. Mulliken charges and Molecular electrostatic potential were also evaluated from DFT calculations. 2016 Elsevier B.V. -
Directional solidification and characterization of InBi1?xSbx crystals
Homogeneous and stoichiometric samples of InBi1?xSbx (x=0, 0.1) crystals have been directionally solidified to explore their suitability for optoelectronic applications. Prior to the growth, the temperature distribution of an indigenously fabricated horizontal furnace has been analysed and optimized to conduct the growth experiments on the basis of phase diagram of the material. Systematic trials have been carried out for several growth runs (48, 60 and 72h) by maintaining an axial temperature gradient of 4, 6 and 8C/cm with the aid of a temperature controller mechanism. The key parameters governing the growth mechanism, composition, phase, and structure of the grown InBi1?xSbx crystals were investigated via X-ray diffraction, scanning electron and atomic force microscopy, Raman and Fourier transform infrared spectroscopy. The presence of secondary phases was ruled out and the average congruent melting points of InBi and InBi0.9Sb0.1 samples were confirmed as 109.43 and 121.13C respectively, by employing differential scanning calorimetric analysis. Investigations on the optical, electrical and mechanical properties of these materials were carried out. Vickers microhardness was found to increase with the Sb incorporation. The average optical band gap computed from the IR transmission spectra was found to be 0.165eV. The results obtained promise that InBi1?xSbx crystals grown by directional solidification are favourable candidates than those grown by other melt methods. 2016, Springer Science+Business Media New York. -
Cattaneo-Christov heat flux on UCM nanofluid flow across a melting surface with double stratification and exponential space dependent internal heat source
Melting and exponential space dependent internal heat source effects on magnetohydrodynamic of upper convected Maxwell liquid towards a horizontal flat surface are addressed. The combined effect of Brownian motion and thermophoresis in nanofluid modeling are retained. The Cattaneo-Christov heat flux model is imposed. Impacts of thermal and solutal stratifications are also accounted. A set of similarity variables are utilized to form ordinary differential system from the prevailing partial differential equations. The problem of ordinary differential system is analyzed numerically through Runge-Kutta-Fehlberg based shooting method. Graphical results of pertinent parameters on the velocity, temperature and nanoparticle concentration are studied. Skin friction coefficient, local Nusselt number and Sherwood number are also addressed. 2017 -
Classification, source, and effect of environmental pollutants and their biodegradation
Any foreign chemical substance that is unusually present within an organism or is unexpectedly found in the environment at a higher concentration than the permissible limits can be termed a xenobiotic or a pollutant. Such substances include carcinogens, drugs, food additives, hydrocarbons, dioxins, polychlorinated biphenyls, pesticides or even some natural compounds. Pollutants are known for their higher persistence and pervasiveness, and along with their transformed products, they can remain in and interact with the environment for prolonged periods. In this article, the classification of such substances based on their nature, use, physical state, pathophysiological effects, and sources is discussed. The effects of pollutants on the environment, their biotransformation in terms of bioaccumulation, and the different types of remediation such as in situ and ex situ remediation, are also presented. 2017 Begell House, Inc. -
Mental health through forgiveness: Exploring the roots and benefits
Forgiveness is conceptualized as the process of making peace with life. The three sources of forgiveness, another person, oneself, and a situation or circumstance are capable of freeing a person from a negative association to the source that has transgressed against a person. Research studies show the mental health benefits associated with forgiveness. The present study explores the experiences of adults who practice forgiveness, specifically, the indicators of forgiveness, the childhood antecedents, and the benefits of forgiving behavior. The study uses a qualitative research approach following a phenomenological framework. A total of 12 adults, ranging from 25 to 40 years of age, who received a high score on Heartland Forgiveness Scale were included in the study. Using semi-structured in-depth interviews, their personal experiences were explored. The data were analyzed using thematic analysis. The themes emerged show that the childhood antecedents of forgiveness are parental influences and early childhood experiences. The indicators of forgiving behavior include positive emotional state, empathy and perspective taking, and religiosity. The themes identified are enhanced sense of well-being, improved self-acceptance, and competence to deal with challenges. Forgiveness enhanced physical and psychological well-being. The findings of the study have several implications for religious leaders, teachers, parents, mental health professionals, and trainers. 2016 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license. -
Impact of macroeconomic variables on the stock performance of select companies in manufacturing industry
The efficient functioning of a stock market is influenced by different macro economic factors like Inflation, Interest rates, exchange rate etc. The favourable Macro Economic Variables both domestic economy and global economy inspire the organisations to go for strategic investment activities in domestic and global markets and reflect positively on the company financial performance and firms fundamentals like Revenues, Operating margins, Earnings Per Share, the Economic Value , Market value, and the Firms overall Value. These positive indicators in the fundamentals of the firms send positive signals into stock markets and generate positive perceptions about the company's stock prices in the market. Markets become so attractive to domestic and foreign investors which drive the share price of different companies , specially Blue chips upwards and creates value to the shareholders .According to the study organized the impact of macro economic variables is not uniform and the impact varies betweem various macro economic variables on the stock market performance. Serials Publications Pvt. Ltd. -
SILICON DEPLETION in the INTERSTELLAR MEDIUM
We report interstellar silicon (Si) depletion and dust-phase column densities of Si along 131 Galactic sight lines using archival observations. The data were corrected for differences in the assumed oscillator strength. This is a much larger sample than previous studies but confirms the majority of results, which state that the depletion of Si is correlated with the average density of hydrogen along the line of sight ( (H) as well as the fraction of hydrogen in molecular form ( f(H2)). We also find that the linear part of the extinction curve is independent of Si depletion. Si depletion is correlated with the bump strength (c3/RV) and the FUV curvature (c4/RV) suggesting that silicon plays a significant role in both the 2175 bump and the FUV rise. 2016. The American Astronomical Society. All rights reserved.