Ewing Christian College

Allahābād, India

Ewing Christian College

Allahābād, India
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Shukla A.K.,Ewing Christian College | Iravani S.,Isfahan University of Medical Sciences
Environmental Chemistry Letters | Year: 2017

Metallic nanoparticles are finding new applications in medical, pharmaceutical, food and agriculture sectors. Applications include drug delivery, targeted cancer remedies, biomarker mapping, gene delivery and molecular imaging. This article reviews green strategies for the preparation of metallic nanoparticles, using enzymes, vitamins, monosaccharides, polysaccharides and biodegradable polymers. Microwave-assisted synthesis is detailed. Then, we review nanoparticle characterization using UV–visible spectroscopy and Fourier transform infrared spectroscopy. We also present applications for water purification. © 2017 Springer International Publishing Switzerland

Nathan R.J.,Lok Nayak Jayaprakash Narayan National Institute of Criminology and Forensic Science | Sharma P.,Lok Nayak Jayaprakash Narayan National Institute of Criminology and Forensic Science | Nathan L.S.,Ewing Christian College
Medico-Legal Update | Year: 2014

Metal toxicity in humans is a result of long term or high level exposure to toxic metals which enter the body through common media as air, water, and food. More recently, with the increase in regular use of numerous cosmetic products, which have been reported to contain heavy metals as contaminants, human bodies are being exposed to them on a daily basis. A number of dermal absorption studies have been conducted which satisfy the assumption that harmful chemicals get absorbed into the blood stream through skin. Hair-dye powders are one of the most commonly used cosmetic products by all- young and old these days and are applied on a regular basis. If contaminated, direct application on hair and scalp can increase chances of absorption of toxic metals as lead and copper and can potentially add up to significant exposure levels as these have cumulative effect. This has drawn our attention to assess the levels of these metals in nine samples of common hair-dye powders available in markets of Delhi. The levels of these metals were determined by Flame Atomic Absorption Spectrophotometer after a wet digestion method for sample preparation. Lead and Copper were detected in different concentrations in all the studied samples, the highest being 1.42 ± 0.0814 ppm and 0.75 ± 0.0693 ppm for lead and copper respectively.

Mishra R.,Allahabad University | Yadav R.S.,Allahabad University | Sanjay S.S.,Ewing Christian College | Pandey A.C.,Allahabad University | Dar C.,Allahabad University
Journal of Experimental Nanoscience | Year: 2010

Highly stable and strong green luminescent ZnO/Cd(OH)2 core-shell nano-particles have been synthesised by simple sol-gel route. X-ray diffraction (XRD) and energy dispersive analysis of X-rays confirm the formation of ZnO/Cd(OH)2 core-shell nanoparticles. The XRD and UV-visible spectroscopy shows that ZnO core size can be efficiently engineered by varying initial precursor ratio. The photoluminescence emission spectra showed the remarkably stable and enhanced visible (green) emission from suspended ZnO/Cd(OH)2 nanoparticles in comparison with bare ZnO nanoparticles. It was postulated that Cd(OH)2 layer at the surface of ZnO nanoparticles prevent the agglomeration of nanoparticles and efficiently assist the trapping of hole at the surface site, a first step necessary for visible emission. © 2010 Taylor & Francis.

Pandey J.D.,Allahabad University | Sanguri V.,Allahabad University | Dwivedi D.K.,Ewing Christian College
Physics and Chemistry of Liquids | Year: 2012

A generalized hole theory for computing the thermodynamic and acoustic properties of liquids and liquid mixtures has been developed. Ultrasonic velocity, isothermal compressibility and thermal expansivity of different pure liquids at 293.15 and 298.15 K are evaluated by using hole theory. The calculated values of ultrasonic velocities, isothermal compressibilities, and thermal expansivities are compared with the experimental findings. A fairly good agreement between experimental and calculated values is observed. © 2012 Copyright Taylor and Francis Group, LLC.

Pandey A.C.,Allahabad University | Sanjay S.S.,Allahabad University | Sanjay S.S.,Ewing Christian College | Yadav R.S.,Allahabad University
Journal of Experimental Nanoscience | Year: 2010

In this work, ZnO nanoparticles (NPs) have been synthesised by hydrothermal method. This hydrothermally synthesised product has been characterised by powder X-ray diffraction and field emission scanning electron microscopy (FE-SEM) for the study of crystal structure and morphology/size. FE-SEM image revealed that ZnO NPs are spherical in shape with a diameter of 20-30 nm. The photoluminescence study of these NPs revealed that ZnO NPs consist of three emission peaks at 401, 482 and 524 nm. The UV emission peak at 401nm is the band edge emission; however, the blue-green emission at 482nm and green emission at 524nm is related to defects. These ZnO NPs are used during the seed germination and root growth of Cicer arietinum. The effect of ZnO NPs has been observed on the seed germination and root growth of C. arietinum seeds. The effect of these ZnO NPs on the reactivity of phytohormones, especially indole acetic acid (IAA) involved in the phytostimulatory actions, is also carried out. Due to oxygen vacancies, the oxygen deficient, i.e. zinc-rich ZnO NPs increased the level of IAA in roots (sprouts), which in turn indicate the increase in the growth rate of plants as zinc is an essential nutrient for plants. © 2010 Taylor & Francis.

Tiwari L.K.,Ewing Christian College
National Academy Science Letters | Year: 2012

In this paper, a fuzzy logic based optimization technique has been adopted to accurately measure software reliability. In the literature, methods like, multiple linear regression, multivariate adaptive regression splines, back propagation trained neural network, dynamic evolving neuro-fuzzy inference system and TreeNet are available. Even a number of models are predicted for software reliability by ensembling the one or more of the above mentioned methods. It has been seen that software reliability cannot be uniformly treated by any one of the above mentioned method as the parameters of software reliability differs in weights depending upon the type of the application. Any application would need a defined recipe of ingredients like- interoperability, scalability, evolvability, pluggability, dynamicity, accuracy, security, cost optimality etc. One or more elements may prevail upon other and be considered as control variables in the optimization techniques applied. The concept calls for an optimization technique when weight can be changed dynamically in parameters depending on the conditionality of responses of the system or the user. This paper introduces the concept of shifting reliability based on dynamic decision making over the various control variables by changing their weight within time-in period in a real time system. Measurement of software reliability, in particular shifting reliability will make the software reliability prediction much more pragmatic in real time system. Digital forensic is in need for a suitable shifting reliability measurement technique. software reliability in case of DF tools governs the legal use. A number of open source tools are waiting for their professional run for want of reliability testing. This paper suggests software reliability testing, even for testing for shifting reliability. A method which has been adapted from simplex method for fuzzy variable linear programming problem has been applied to the particular case study. Typical formulation of fuzzy optimization depends on piece wise linear membership function. Linear member ship function introduces regions of no differentiability. In fact no deterministic method can be applied for fuzzy optimization, utilization of continuous differentiable membership function permits the use of gradient base methods. An expression for the gradient base decision degree function is available in literature. This formulation has been applied in a case study having a number of control variables using a suitable tool e.g. ProjectSixPap. © The National Academy of Sciences, India 2012.

Maurya G.S.,Allahabad University | Jyotsana A.,Allahabad University | Pathak A.K.,Ewing Christian College | Kumar A.,Indian Institute for Plasma Research | Rai A.K.,Allahabad University
Optics and Lasers in Engineering | Year: 2014

Laser induced breakdown spectroscopy (LIBS) spectra of optical window and flange of Aditya tokamak have been recorded in the spectral range of 200-500 nm in open atmosphere. For qualitative analysis of these samples, the intensity variation of elemental impurities (Fe, Cr, Ni, Mn, Mo, Cu and C) on the surface of optical window and flange with radial distance has been studied. Depending on thickness of thin films of impurity, four different concentric color rings are observed on the surface of the flange. On moving from reddish brown to indigo color ring, the trends in spectral intensity of these impurities are found in decreasing order. Comparative spectral intensity variation of impurities in both the samples reveals that the impurity deposition on the flange surface is more in comparison to the optical window. Our study demonstrates the capability of LIBS to analyze the spatial distribution of deposited impurities on window and flange samples. © 2013 Elsevier Ltd.

Mishra S.K.,Ewing Christian College | Srivastava G.K.,Allahabad University
Phytomorphology: An International Journal of Plant Morphology | Year: 2015

The pollen grains of the genera Cassia L. and Senna Mill, belonging to stenopalynous subtribe Cassiinae are generally radially symmetrical, isopolar, trizonocolporate or trizonocolpate. The shape varies from oblate-spheroidal to prolate. The sporoderm patterns may range from reticulate, foveolate, perforate, rugulate to verrucate and tuberculate in different species. The palynological data particularly the shape and sporoderm stratification provide crucial taxonomic information for delimiting the closely related Senna obtusifolia and Senna tora. In the former the large anther having bottleneck-like apex has pollen grains with psilate exine pattern while in the latter, subprolate pollen grains with warty and verrucate exine patterns are produced in the large anthers with rounded apex. Palynological data also provide valuable information in establishing the taxonomic relationship between some other closely related red Cassia and Senna species of the Indian Cassiinae. Despite their role in resolving the taxonomic riddles, the utility of pollen morphology in taxonomy of sub-tribe Cassiinae appears to be very limited.

Kripal R.,Allahabad University | Shukla A.K.,Ewing Christian College
Spectroscopy Letters | Year: 2010

Electron paramagnetic resonance (EPR) studies of VO2+ impurity ion in single crystals of diammonium hexaaqua magnesium(II) sulfate are carried out at 9.5 GHz (X-band) at room temperature. Different spin-Hamiltonian parameters are determined. VO2+ is expected to enter the lattice substitutionally. Superhyperfine splitting is also observed. An EPR study of a powder sample is done that supports the data obtained from single crystal studies. Optical absorption studies are also performed at room temperature. The crystal field parameter (DVOq), tetragonal parameters (Ds and Dt), and various bonding parameters are evaluated to estimate the covalency and nature of bonding of VO2+ with its different ligands. © Taylor & Francis Group, LLC.

Mishra R.,Allahabad University | Yadav R.S.,Allahabad University | Pandey A.C.,Allahabad University | Sanjay Sharda.S.,Ewing Christian College | Dar C.,Allahabad University
Journal of Luminescence | Year: 2010

We report the formation of highly stable and luminescent ZnO@Cd(OH)2 core-shell nanoparticles by simple introduction of cadmium salt in the initial precursor solution, used to synthesize ZnO nanoparticles by sol-gel route. The cadmium to zinc salt concentration ratio has been also varied to control the growth of ZnO nanoparticles at the smaller particle size. Formation of ZnO@Cd(OH)2 core-shell nanostructure has been confirmed by X-ray diffraction (XRD), energy dispersive analysis of X-rays (EDAX) and X-ray photoelectron spectroscopy (XPS). UV-vis absorption spectroscopy exhibits blue-shift in absorption edge on increasing cadmium concentrations. The photoluminescence emission spectra showed the remarkably stable and enhanced visible (green) emission from suspended ZnO@Cd(OH)2 nanoparticles in comparison to bare ZnO nanoparticles. It is postulated that Cd(OH)2 layer at the surface of ZnO nanoparticles prevents the agglomeration of nanoparticles and efficiently assists the trapping of hole at the surface site, a first step necessary for visible emission. The Fourier transform infrared spectroscopy (FTIR) also supports our assumption about surface chemistry. © 2009 Elsevier B.V. All rights reserved.

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