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Dehradun, India

Kumar R.,DBS PG College | Sharma M.L.,Indian Institute of Technology Roorkee
Himalayan Geology | Year: 2011

Keeping in view the problem of increasing concern of the likelihood of occurrence of the next large earthquake in the seismically active regions in India where the last occurrence has crossed the return periods, the conditional probabilities have been estimated using Weibull and Gaussian distribution for the Indian region. The estimations have been carried out by dividing the Indian subcontinent into 24 seismogenic sources. The cumulative and conditional probabilities have been interpreted with respect to the last earthquake occurrence and in the time intervals of 15 and 50 years. Most of the regions in the country are found to be having lesser seismic hazard as compared with the results produced using classical probabilistic seismic hazard estimations. The use of conditional probabilities have been recommended for estimation of seismic hazard to take into account the last occurrence of earthquake in the region. Source

Dubey P.,Indian Institute of Technology Roorkee | Arya V.,Indian Institute of Technology Roorkee | Srivastava S.,DBS PG College | Singh D.,Indian Institute of Technology Roorkee | Chandra R.,Indian Institute of Technology Roorkee
Surface and Coatings Technology | Year: 2015

The effect of microstructure on thermal stability and mechanical properties of co-sputtered deposited Zr-W-B-N thin films on Si (100) substrates have been studied in detail. The power density of boron target has been varied from 0.1 to 7.5W/cm2 to obtained films of varying microstructure. Electron microscopy, X-ray diffraction analysis, atomic force microscopy, Raman scattering spectra, nano and micro indentations were used to investigate the interrelations between the microstructure and the variations in strength properties of nanocomposite Zr-W-B-N thin films. It has been observed that films with boron content<2.3at.% exhibited (200) preferred crystallographic orientation of grains and columnar structure. While the films of boron content ≥7.5at.% are columnarless with crystal phase grain size less than 7nm and of amorphous-crystalline structure. The film with boron concentration ~7.5at.% exhibits maximum hardness (~37GPa), wear resistance (H/Er ~0.24) and fracture toughness (2.9MPa·m1/2). Post annealing of the film with ~7.5at.% boron concentration has been carried out in vacuum (Tv) and air (Tn) up to 900°C. Zr-W-B(7.5at.%)-N film retains its fcc structure during vacuum annealing up to 900°C. Oxygen starts to incorporate at Tn =500°C and its percentage goes up with increasing Tn up to 900°C. © 2015 Elsevier B.V. Source

Muruganandam M.,Central Soil and Water Conservation Research and Training Institute CSWCRTI | Pande R.K.,DBS PG College | Sharda V.N.,Agricultural Scientists Recruitment Board ASRB | Mishra P.K.,CSWCRTI
Indian Journal of Traditional Knowledge | Year: 2014

A study carried out to assess existing basic knowledge and perceptions of farmers on fish farming in Uttarakhand Himalayas during 2003-08 indicated prevalence of as many as 16 mythical superstitions on fish identification, features of fishponds and various attributes of fishes or fish farming among farmers adding to already existing problems of fisheries development in the region. Preference for deeper fishponds or water harvesting structures (WHS) and coldwater river fishes against farmed or warm water river fishes; ignorance on the needs of liming or fertilization in fishponds and various benefits of fishes or fish farming other than for food purpose were widely held by 81-86% respondents. Ignorance on the negative impacts of fishing in rivers using powder prepared from the woody shrub, Zanthoxylum armatum DC., locally called as timru was observed in 69% respondents and probably this helps to continue periodically organized traditional fishing festivals, known as mound or machli mela using timru powder, that destroy riverine ecosystems in the region. Importance of water management in fish farming and potential of pig rearing or use of pig dung as fertilizer in fishponds or crop fields were not recognized by 50% respondents. Overall, ignorance on various principles, recommended practices and inputs of fish farming, features of fishes and fishing in rivers were prevalent in the region. A review made on issues of prevailing superstitions provided scientific and logical explanations either in support of them or otherwise. The paper identifies possible researchable issues associated with the myths and suggests dispelling unscientific superstitions maybe through appropriate research findings, trainings and positive demonstrations by the existing advisory systems. Source

Joshi D.P.,DBS PG College | Sharma K.,Graphic Era University | Gill F.S.,Graphic Era University
Indian Journal of Pure and Applied Physics | Year: 2013

In the present paper, the dependence of transfer characteristics of PX-Si TFT devices on gate oxide thickness (tox) and inversion layer thickness (tsi) has been investigated theoretically by considering a new Gaussian energy distribution of GB trapping states. The dependence of drain current (ID) and GB space charge potential barrier height (q V g) of PX-Si TFT on gate voltage (VGS) at different inversion layer thickness qV g, and oxide layer thickness has also been studied. It is observed that the drain current increases on decreasing the thickness of oxide layer and inversion layer. Source

Singh A.K.,Indian Institute of Technology Roorkee | Chauhan S.,Indian Institute of Technology Roorkee | Srivastava S.K.,DBS PG College | Chandra R.,Indian Institute of Technology Roorkee
Solid State Communications | Year: 2016

The structural and magnetic properties of polycrystalline Nd2NiMnO6 (NNMO) synthesized by solid state reaction method have been investigated. Rietveld refinement of Powder X-Ray diffraction data suggests that NNMO compound crystallizes in monoclinic phase with space group P21/n. Magnetic measurements reveal an additional magnetic transition TC'~85K due to to Ni3+-O-Mn3+ antiferromagnetic superexchange interaction along with ferromagnetic transition ~196K in M-T curve, leading to antiferromagnetic interactions in this compound. High sintering temperature (upto 1100°C) leads to the formation of antisite disorders and antiferromagnetic antiphase boundaries in the present sample. The magnetic hysteresis measurements show ferromagnetic behavior with low saturation magnetization value (~2μB/f.u.) than the theoretical spin-only value (5μB/f.u.) of Ni/Mn ions. Hence, antisite disorders diminish the long range ferromagnetic ordering and also affect the magnetic properties of this compound. Exchange bias behavior has been observed in the hysteresis loops when the sample was field cooled from 300K to 5K. Exchange coupling between the ferromagnetic moments and antiferromagnetic antiphase boundaries is responsible for the observation of exchange bias in the present system. © 2016 Elsevier Ltd. Source

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