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New Delhi, India

Sajdha,Jammu University | Sheikh H.N.,Jammu University | Kalsotra B.L.,Jammu University | Kumar N.,Defence Laboratory | Kumar S.,DRDO
Bulletin of Materials Science

Nanocomposites of mixed oxides of iron and neodymium in polymer matrix of anilineformaldehyde are reported. The composites have been obtained by treating the aqueous solution of aniline, hydrochloric acid and formaldehyde with halide of iron and neodymium oxide. The infra-red spectra show broad peaks at ̃ 590 cm-1 and at ̃ 610 cm-1 due to the presence of oxides of both iron and neodymium. In heated samples, the absorption peaks due to metal oxides are better resolved. A broad and strong peak in XRD spectra at 2θ value of 35·69920 corresponds to spinel γ-Fe 2O3. 57Fe Mössbauer spectrum for unheated sample gives Mössbauer parameters, i.e. isomer shift (δ), quadrupole splitting (ΔE) and effective magnetic field (Heff). Transmission electron microscopy (TEM) micrographs reveal well dispersed particles at different magnifications. Vibrating sample magnetometry (VSM) studies indicate that the ferrite nanoparticles exhibit characteristics of ferromagnetism. © Indian Academy of Sciences. Source

Rani R.,Electroceramics Research Laboratory | Rani R.,Thapar University | Singh S.,GVM Girls College | Juneja J.K.,Hindu College | And 2 more authors.
Ceramics International

Material series with compositional formula Ba0.9Sr 0.1ZrxTi1-xO3 (BSZT) were prepared by conventional solid state reaction route. XRD pattern shows that all the samples are well crystallized into perovskite structure. Tetragonality was found to decrease with increase in Zr content. Effect of substitution of Zr on dielectric constant, tangent loss and nature of transition temperature is discussed in the present paper. © 2011 Elsevier Ltd and Techna Group S.r.l. Source

Viswambaran M.,Military Dental Center | Arora V.,Addl DGDS | Tripathi R.C.,DRDO | Dhiman R.K.,Armed Forces Medical College
Medical Journal Armed Forces India

Background: The immediate placement of implants into fresh extraction socket has proven to be a safe and predictable procedure. However, there is lack of scientific evidence regarding the healing pattern and osseointegration associated with immediate implants especially with different grafting materials. Methods: A total of 30 patients male or female, with a mean age of 23.1 years ± 6.0 in the age group of 18e38 years, each having at least one tooth indicated for extraction (either maxillary or mandibular anterior teeth) were selected and randomly divided in to two groups. 30 Implants (Xive® friadent, Germany) were placed into fresh extraction sockets during this study. Two types of graft materials namely Dembone® (freeze-dried bone allograft) for group A and G-Bone® (modified hydroxyapatite) for group B were used. After implant placement all implants were evaluated clinically and radiographically at baseline, 3 months, 6 months, 9 months and 12 months. All clinical and radiographic parameters were subjected to statistical analysis. Intragroup comparisons were made with paired 't' test and intergroup comparisons with unpaired 't' test (P > 0.05 NS, ≤0.05 S, ≤0.01 HS). Result: During the 1-year interval, no implant was lost and the mean bone level at the implants was maintained or even improved. Conclusion: Immediate restoration of single tooth implants placed in fresh extraction sockets could be considered a valuable option to replace a missing tooth. The graft materials used in both groups have been found to be equally effective. © 2012, Armed Forces Medical Services (AFMS). All rights reserved. Source

Kumar B.P.,center | Kumar H.H.,center | Kharat D.K.,DRDO | Balasubramanian M.,Indian Institute of Technology Madras | Murty B.S.,Indian Institute of Technology Madras
Synthesis and Reactivity in Inorganic, Metal-Organic and Nano-Metal Chemistry

The ferroelectric Pb(Zrx Ti1-x)O3, lead zirconate titanate (PZT) ceramics are well-known piezoelectric materials for electro-mechanical transducers. In the present studies, Ta-doped PZT ceramics were prepared by kinetic energy processing and solid-state oxide route. X-ray diffraction (XRD) studies are done to determine the presence of perovskite phase in sintered PZT ceramics. Microstructural studies were carried out by using scanning electron microscope (SEM) and atomic force microscope (AFM). Detailed dielectric and piezoelectric studies were carried out for the sintered samples. Ta-doped PZT ceramics prepared by kinetic energy processing route followed by sintering has higher dielectric constant, compared to conventionally prepared PZT. © 2014 Copyright Taylor & Francis Group, LLC. Source

Kumar B.S.S.,CSE | Manjunath A.S.,SIT | Christopher S.,DRDO | Menon R.,CABS
Procedia Computer Science

The scalable Video is the most suitable video format for the current day scenario where there are different varieties of electronic gadgets used to communicate and play back. As the device resolution varies, the codec designed for Scalable video (H.264/AVC) is the only solution for its support. But the challenge is in its transmission due to the limited network resources in wireless networks viz; bandwidth. This introduces jitter during video playback. This needs an effective Compression technique to reduce the possible transmission time. The paper presents a novel Adaptive Dual Tree Complex wavelet Transoform (ADT-CWT) using the efficient Motion Block Estimation (MBE), Diamond search with Large Diamond Search Path (LDSP) and a Small Diamond Search Path (SDSP). This technique effectively improves the performance of Scalable Video in wireless transmission. The PSNR and the Compression Ratio (CR) are considered for the comparison. © 2016 Published by Elsevier B.V. Source

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