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Singh N.,Vellore Institute of Technology | Balasubramanian K.,Defence Evaluation and Research Agency
RSC Advances | Year: 2014

Speciation and recovery of U(vi) ions from nuclear wastewater is a heavy challenge for various nuclear centers and research organizations. In this perspective, the present research work aims at using cost effective cellulose nanofibers for the reclamation of these incurable ions. Cellulose nanofibers were synthesized by electrospinning and functionalized with carbon nanoparticles (CNPs) obtained from the camphor soot with noticeable metal sorption capacity. Sorption capability was ascertained by conducting systematic batch experiments for the optimization of parameters such as CNP dosage, pH selectivity, and dosage of nanofibers. The results indicated fast uptake of U(vi) ions, which was significantly observed at pH 6 with an adsorption percentage of 97 from mimicked solution within a period of 120 minutes. 85% of U(vi) was removed from an aqueous solution with an adsorbent dosage of 50 mg. The maximum adsorption capacity was noted to be 410 mg g-1 with 96% adsorption at varying concentration within a period of 60 min. Adsorptive uptake capacity of U(vi) ions was described with adsorption isotherms (Langmuir, Freundlich, Temkin and Dubinin-Radushkevich). Pseudo first order and Elovich model defined the sorption kinetics with good correlation regression values (R2 = 0.99). The cellulose-camphor soot nanofibers were characterized by field emission scanning electron microscopy (FESEM), Fourier transform infrared-spectroscopy (FT-IR), X-ray diffraction (XRD) and Raman spectroscopy. Further, thermodynamic parameters such as standard free energy (ΔG0), standard enthalpy (ΔH0) and standard entropy (ΔS0) revealed that the adsorption process was endothermic and spontaneous for the uptake of U(vi) ions. Reusability of the fibers was effectively performed with 0.1 M CH3COOH and HCOOH with contact duration of 30 min. This journal is © the Partner Organisations 2014. Source

Connolly M.J.,Defence Evaluation and Research Agency
Journal of the Royal Army Medical Corps | Year: 2015

The period to 2035 is likely to be characterised by instability between states and in relations between groups within states. It is predicted to include climate change, rapid population growth, resource scarcity, resurgence in ideology, and shifts in power from west to east. Many of these changes are likely to have an impact on the health of civil societies and those military personnel deployed by states to counter these challenges. This paper considers the potential impact of emerging global strategic trends on health service support (HSS) in the Future Operating Environment 2035. Global Strategic Trends—Out to 2040, The Future Character of Conflict and NATO Strategic Foresight Analysis Report 2013 provide the foundations of the paper. The study concludes that future impacts on HSS are neither completely predictable nor predetermined, and there is always a possibility of a strategic shock. Knowledge of vulnerability, however, allows an informed approach to the development and evaluation of adaptive strategies to lessen risks to health. © 2015, Royal Army Medical College. All rights reserved Source

Gould M.,Defence Evaluation and Research Agency
Military Medicine | Year: 2011

Objective: Knowledge of patients' preferences of military mental health care is required to inform service planning. The objective was to inform service planning by quantifying, and identifying predictors of, patient preferences for mental health care providers and location of facilities. Method: Sociodemographic and service characteristics and concerns about stigma were investigated for patients presenting to 4 U.K. Armed Forces Departments of Community Mental Health over a 2-months period (n = 163). Results: 5% preferred to be seen by a uniformed mental health clinician, 30% by a nonuniformed clinician, and 65% reported no preference. Gender and service were associated with care provider preference and service was associated with location preference. Conclusion: The Armed Forces need to explore and identify ways of accommodating their patients' preference, especially regarding the uniformed status of their care provider, to achieve good engagement and acceptability. Source

Balasubramanian K.,Defence Evaluation and Research Agency | Kodam K.M.,University of Pune
RSC Advances | Year: 2014

Electrospinning, a feasible nanotechnology, has been exploited to engineer polyacrylonitrile (PAN) nanofibrous mats enclosing a representative hydrophobic drug like essential oil of lavender. The incorporation of electrolytic solution (NaCl) to polymer solution enhanced the electrospinning capability. Concentration as small as 0.3% (w/w) of electrolyte resulted in significant nanofibre morphologies, reduced average fibre diameter (88.44 nm) and it exhibited a narrow degree of polydispersity. The dosage of drug loaded in PAN nanofibres were varied from 12.5 to 200 μg mL-1 and their cytotoxicity against mouse fibroblast NIH/3T3 were studied in vitro. The antibacterial proficiency was gauged by challenging the material against Staphylococcus aureus and Klebsiella pneumoniae bacteria. The PAN nanofibres exhibited effective bactericidal properties of 14-15 mm zone of inhibition in at least 8 h, and it remained unaltered over 30 days. The in vitro release of the drug resulted in a dual drug release profiles with an initial burst as well as the diffusion dominated release, ensuing an enduring antibacterial activity. The incorporation of lavender oil improved the thermal stability resulting in a 20% residual mass at 800 °C, higher than pristine PAN nanofibers. The modelling of the interactions between PAN and the major antimicrobial components of lavender was performed to understand the chemistry between the additive and polymer. Thus, PAN nanofibres can be used to be a promising antibacterial material in various fields like biomedical, textile and water treatment applications. © 2014 the Partner Organisations. Source

Deirmenci E.,Defence Evaluation and Research Agency | Husnu Dirikolu M.,Istanbul University
Applied Thermal Engineering | Year: 2012

A finite element thermo-mechanical analysis of firing through a gun barrel requires the convection heat transfer coefficient values under high temperature and pressure among input parameters. A thermochemical approach has been formulated in order to obtain these coefficients. Considering a variable burning speed for a typical gunpowder configuration, the variation of pressure wave speed, density, and heat conduction of the burning gas mixture is used to evaluate the Reynolds and Prandtl numbers along the barrel axis. These two numbers are then used to calculate the Nusselt numbers from which the continuously changing convection heat transfer coefficients are determined. It is confirmed from an experimental firing process and its corresponding thermo-mechanical finite element analysis that the calculated coefficients present a good estimate of the real coefficients. © 2011 Elsevier Ltd. All rights reserved. Source

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