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Pawan K. Khanna

Bio: Pawan K. Khanna is an academic researcher from Defence Institute of Advanced Technology. The author has contributed to research in topics: Nanoparticle & Scanning electron microscope. The author has an hindex of 33, co-authored 151 publications receiving 4293 citations. Previous affiliations of Pawan K. Khanna include Defence Research and Development Organisation & University of St Andrews.


Papers
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TL;DR: Findings, for the first time, indicate that silver nanoparticles promote the growth of B. juncea seedlings by modulating their antioxidant status.
Abstract: Metal nanoparticles can potentially be used as tools for engineering biological redox reactions. Present study underlines the effect of silver metal nanoparticles (at 0, 25, 50, 100, 200 and 400 ppm) on the growth and antioxidant status of 7-day-old Brassica juncea seedlings. Fresh weight, root and shoot length, and vigor index of seedlings is positively affected by silver nanoparticle treatment. It induced a 326 % increase in root length and 133 % increase in vigor index of the treated seedlings. Improved photosynthetic quantum efficiency and higher chlorophyll contents were recorded in leaves of treated seedlings, as compared to the control seedlings. Levels of malondialdehyde and hydrogen peroxide decreased in the treated seedlings. Nanoparticle treatment induced the activities of specific antioxidant enzymes, resulting in reduced reactive oxygen species levels. Decrease in proline content confirmed the improvement in antioxidant status of the treated seedlings. The observed stimulatory affects of silver nanoparticles are found to be dose dependent, with 50 ppm treatment being optimum for eliciting growth response. Present findings, for the first time indicate that silver nanoparticles promote the growth of B. juncea seedlings by modulating their antioxidant status.

400 citations

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TL;DR: In this paper, the reduction of silver salt in aqueous PVA with SFS is done for the first ever time, and the solutions and the films are characterized by using UV-vis, photoluminescence (PL), FTIR spectroscopy, XRD, SEM, TEM and thermal analysis.

356 citations

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TL;DR: In this article, the effect of Gold-nanoparticles on the growth profile and yield of Brassica juncea, under field conditions, was investigated using atomic absorption spectroscopy.
Abstract: Experiments were carried out to determine the effect of Gold-nanoparticles on the growth profile and yield of Brassica juncea, under field conditions. Five different concentrations (0, 10, 25, 50 and 100 ppm) of Gold-nanoparticles were applied through foliar spray. Presence of Gold-nanoparticles in the leaf tissues was confirmed through atomic absorption spectroscopy. Various growth and yield related parameters, including plant height, stem diameter, number of branches, number of pods, seed yield etc. were positively affected by the nanoparticle treatment. Gold-nanoparticle treatment increased the number of leaves per plant; however the average leaf area was not affected. Optimal increase in seed yield was recorded at 10 ppm of Gold-nanoparticle treatment. Reducing as well as total sugar contents increased up to 25 ppm of Gold-nanoparticle treatment. Application of nanoparticles also improved the redox status of the treated plants. The results, for the first time, demonstrate successful use of Gold-nanoparticles in enhancing growth and yield of B. juncea, under actual field conditions and present a viable alternative to GM crops for ensuring food security.

304 citations

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TL;DR: In this article, a similar reaction with hydrazine hydrate (HH) and sodium formaldehyde sulfoxylate (SFS) in polymer afforded only a mixture of Cu 2 O and Cu.

251 citations

Journal ArticleDOI
TL;DR: In this paper, a reduction of the silver salt in aqueous aniline leads to the formation of silver nanoparticles which in turn catalyze oxidation of anilines to polyaniline.

216 citations


Cited by
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Journal ArticleDOI
TL;DR: This review presents an overview of silver nanoparticles (Ag NPs) preparation by green synthesis approaches that have advantages over conventional methods involving chemical agents associated with environmental toxicity.

3,290 citations

Journal ArticleDOI
TL;DR: The reduction of [Ag(NH(3))(2)](+) by maltose produced silver particles with a narrow size distribution with an average size of 25 nm, which showed high antimicrobial and bactericidal activity against Gram-positive and Gram-negative bacteria, including highly multiresistant strains such as methicillin-resistant Staphylococcus aureus.
Abstract: A one-step simple synthesis of silver colloid nanoparticles with controllable sizes is presented. In this synthesis, reduction of [Ag(NH3)2]+ complex cation by four saccharides was performed. Four saccharides were used: two monosaccharides (glucose and galactose) and two disaccharides (maltose and lactose). The syntheses performed at various ammonia concentrations (0.005−0.20 mol L-1) and pH conditions (11.5−13.0) produced a wide range of particle sizes (25−450 nm) with narrow size distributions, especially at the lowest ammonia concentrations. The average size, size distribution, morphology, and structure of particles were determined by dynamic light scattering (DLS), transmission electron microscopy (TEM), and UV/Visible absorption spectrophotometry. The influence of the saccharide structure (monosacharides versus disaccharides) on the size of silver particles is briefly discussed. The reduction of [Ag(NH3)2]+ by maltose produced silver particles with a narrow size distribution with an average size of ...

2,184 citations

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TL;DR: In this paper, the surface of inorganic nanoparticles is modified to improve the interfacial interactions between the inorganic particles and the polymer matrix, which improves the properties of polymeric composites.

1,709 citations

Journal ArticleDOI
TL;DR: A detailed discussion on the mechanism of electrical conduction in PANI and the factors those influence the conductivity of PANI is also included in this paper, where the problems of effective utilization and the methods adopted to overcome these problems are also provided.

1,632 citations