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First principle study of structural,electronic and thermodynamic behavior of ternary intermetallic compound:CeMgTl

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Journal of Magnesium and Alloys 2014年第4期2卷 349-356页

作者： r.p.singh Department of physics S.S.V.Degree CollegeAffiliated to C.C.S.University-MeerutHapurU.P.India

To study the structural,electronic and thermodynamic behavior of CeMgTl,full-potential linear augmented plane wave plus local orbital(Fp-LApW+lo)method has been *** lattice parameters(a_(0),c_(0)),bulk modulus(B_(0))and its first order pressure derivative(B_(0)′)have been calculated for *** structure and density of states histograms depicts that“5d”orbital electrons of Tl have dominant character in the electronic contribution to *** of the temperature and pressure on unit cell volume,bulk modulus,Debye temperature,Grüneisen parameter,specific heat and thermal expansion coefficient(α)have been studied in wide temperature range(0-300 k)and pressure range(0-15 Gpa).

关键词： Intermetallics Structural properties Electronic structure Thermodynamic properties

Nonlinear Coupling of kinetic Alfvén Waves and Ion Acoustic Waves in the Inner Heliosphere

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research in Astronomy and Astrophysics 2024年第10期24卷 141-158页

作者： Mani k.Chettri Vivek Shrivastav rupak Mukherjee Nidhi Gaur r.p.Sharma Hemam D.singh Department of physics Sikkim UniversityGangtokSikkimIndia DAV public School Sector 14GurugramHaryanaIndia plasma Simulation Laboratory Department of Energy Science and EngineeringIndian Institute of Technology DelhiDelhiIndia

We study the nonlinear coupling of kinetic Alfvén waves with ion acoustic waves applicable to the Earth’s radiation belt and near-Sun streamer belt solar wind using dynamical equations in the form of modified Zakharov *** simulations show the formation of magnetic field filamentary structures associated with density humps and dips which become turbulent at later times,redistributing the energy to higher *** magnetic power spectra exhibit an inertial range kolmogorov-like spectral index value of-5/3 for k_(⊥)ρ_(i)per dissipation range spectra with indices~-3 for the radiation belt case and~-4 for the nearSun streamer belt solar wind case,here k_(⊥)andρ_(i)represent the wavevector component perpendicular to the background magnetic field and the ion thermal gyroradius,*** quasilinear theory in terms of the Fokker-planck equation in the region of wavenumber turbulent spectra,we find the particle distribution function flattening in the superthermal tail population which is the signature of particle energization and plasma heating.

关键词： Sun:chromosphere Sun:corona Sun:heliosphere

Water-Extractable Carbon pools and Microbial Biomass Carbon in Sodic Water-Irrigated Soils Amended with Gypsum and Organic Manures

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pedosphere 2013年第1期23卷 88-97页

作者： O.p.CHOUDHArY J.k.GILL BIJAY-singh Department of Soil Science Punjab Agricultural University School of Earth and Environment University of Western Australia

Microbial biomass carbon (MBC), a small fraction of soil organic matter, has a rapid turnover rate and is a reservoir of labile nutrients. The water-extractable carbon pools provide a fairly good estimate of labile C present in soil and can be easily quantified. Changes in soil MBC and water-extractable organic carbon pools were studied in a 14-year long-term experiment in plots of rice-wheat rotation irrigated with canal water (CW), sodic water (SW, 10-12.5 mmol c L-1 residual sodium carbonate), and SW amended with gypsum with or without application of organic amendments including farmyard manure (FYM), green manure (GM), and wheat straw (WS). Irrigation with SW increased soil exchangeable sodium percentage by more than 13 times compared to irrigation with CW. Sodic water irrigation significantly decreased hot water-extractable organic carbon (HWOC) from 330 to 286 mg kg-1 soil and cold water-extractable organic carbon (CWOC) from 53 to 22 mg kg-1 soil in the top 0-7.5 cm soil layer. In the lower soil layer (7.5-15 cm), reduction in HWOC was not significant. Application of gypsum alone resulted in a decrease in HWOC in the SW plots, whereas an increase was recorded in the SW plots with application of both gypsum and organic amendments in both the soil layers. Nevertheless, application of gypsum and organic amendments increased the mean CWOC as compared with application of gypsum alone. CWOC was significantly correlated with MBC but did not truly reflect the changes in MBC in the treatments with gypsum and organic amendments applied. For the treatments without organic amendments, HWOC was negatively correlated with MBC (r = 0.57*) in the 0-7.5 cm soil layer, whereas for the treatments with organic amendments, both were positively correlated. Irrigation with SW significantly reduced the rice yield by 3 t ha-1 and the yield of rice and wheat by 5 t ha-1 as compared to irrigation with canal water. Application of amendments significantly increased rice and wheat yields.

关键词： cold water exchangeable sodium percentage hot water organic carbon yield

pApr reduction in Massive MU-MIMO-OFDM Systems Using the proximal Gradient Method

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Journal of Communications and Information Networks 2019年第1期4卷 88-94页

作者： Davinder singh r.k.Sarin Department of Electronics and Communication Engineering Dr.B.R.Ambedkar National Institute of TechnologyJalandharPunjabIndia-144011

In this paper,we address the issue of peak-to-average power ratio(pApr)reduction in large-scale multiuser multiple-input multiple-output(MU-MIMO)orthogonal frequency-division multiplexing(OFDM)*** reduction and the multiuser interference(MUI)cancellation problem are jointly formulated as an l_(∞)-norm based composite convex optimization problem,which can be solved efficiently using the iterative proximal gradient *** proximal operator associated with l_(∞)-norm is evaluated using a low-cost sorting *** proposed method adaptively chooses the step size to accelerate *** results reveal that the proximal gradient method converges swiftly while provid-ing considerable pApr reduction and lower out-of-band radiation.

关键词： OFDM MU-MIMO pApr reduction proximal operator proximal gradient method

Lightweight convolutional neural network models for semanticsegmentation of in-field cotton bolls

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Artificial Intelligence in Agriculture 2023年第2期8卷 1-19页

作者： Naseeb singh V.k.Tewari p.k.Biswas L.k.Dhruw Department of Agricultural and Food Engineering IIT KharagpurKharagpur 721302India Department of Electronics and Electrical Communication Engineering IIT KharagpurKharagpur 721302India

robotic harvesting of cotton bolls will incorporate the benefits of manual picking as well as mechanical harvesting. For robotic harvesting, in-field cotton segmentation with minimal errors is desirable which is a challengingtask. In the present study, three lightweight fully convolutional neural network models were developed for thesemantic segmentation of in-field cotton bolls. Model 1 does not include any residual or skip connections,while model 2 consists of residual connections to tackle the vanishing gradient problem and skip connectionsfor feature concatenation. Model 3 along with residual and skip connections, consists of filters of multiplesizes. The effects of filter size and the dropout rate were studied. All proposed models segment the cotton bollssuccessfully with the cotton-IoU (intersection-over-union) value of above 88.0%. The highest cotton-IoU of91.03% was achieved by model 2. The proposed models achieved F1-score and pixel accuracy values greaterthan 95.0% and 98.0%, respectively. The developed models were compared with existing state-of-the-art networks namely VGG19, resNet18, EfficientNet-B1, and InceptionV3. Despite having a limited number of trainableparameters, the proposed models achieved mean-IoU (mean intersection-over-union) of 93.84%, 94.15%, and94.65% against the mean-IoU values of 95.39%, 96.54%, 96.40%, and 96.37% obtained using state-of-the-art networks. The segmentation time for the developed models was reduced up to 52.0% compared to state-of-theart networks. The developed lightweight models segmented the in-field cotton bolls comparatively faster andwith greater accuracy. Hence, developed models can be deployed to cotton harvesting robots for real-time recognition of in-field cotton bolls for harvesting.

关键词： Cotton Semantic segmentation Convolutional neural network robotic harvesting Image segmentation Deep learning

Synthesis and evaluation of novel analogues of mangiferin as potent antipyretic

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Asian pacific Journal of Tropical Medicine 2011年第11期4卷 866-869页

作者： Shashi kant singh Saurabh k Sinha Sk prasad r kumar Bhawani S Bithu S Sadish kumar p singh Varanasi College of pharmacy Uttar PradeshVaranasiIndia Department of pharmaceutics Institute of TechnologyBanaras Hindu UniversityVaranasiUttar PradeshIndia Institute of Technology and Sciences Paramedical College(Pharmacy)MuradnagarUttar PradeshIndia Uday pratap College VaranasiUttar PradeshIndia

Objective:To screen different analogues of mangiferin pharmacologically for antipyretic activity. Methods:The naturally occurring xanthone glycoside mangiferin was isolated by column chromatography from the elhanolic extract of stem bark of Mangifera *** was further converted to 5-(N-phenylamino methyleno) mangiferin.5-(N-p-chlorophenylamino methyleno) mangiferin,5-(N-2-methyl phenylamino methyleno) mangiferin.5-(N-p-methoxy phenylamino methyleno) mangiferin.5-(N,N-diphenylamino methyleno) mangiferin,5-(N-α-napthylamino methyleno) mangiferin and 5-(N-4-methyl phenylamino methyleno) mangiferin *** synthesized compounds were further screened for antipyretic activity along with mangiferin at a dose level of 100 and 200 tng/*** and its analogues were characterized by melting point and r_f value determination and through spectral technique like UV,Ir,and NMr spectral ***:The antipyretic activity of mangiferin as well as all analogues was found to be more significant in at higher dose ie.200 mg/kg which was depicted thmugh a decrease in rectal temperature up to 3 ***:The antipyretic activity of mangiferin and its analogues may be attributed to inhibition in synthesis of TNF-αand anti-oxidant activity associated with amelioration of inflammatory actions of cytokines.

关键词： Mangifera indica Mangiferin Antipyretic

plant Species Diversity along an Altitudinal Gradient of Bhabha Valley in Western Himalaya

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Journal of Mountain Science 2008年第2期5卷 157-177页

作者： Amit Chawla S.rajkumar k.N.singh Brij Lal r.D.singh A.k.Thukral Bioresource Development Unit Institute of Himalayan Bioresource Technology (CSIR) Palampur Himachal Pradesh-176 061 India Department of Botanical & Environmental Sciences Guru Nanak Dev University Amritsar-143 005 India

The present study highlights the rich species diversity of higher plants in the Bhabha Valley of western Himalaya in India. The analysis of species diversity revealed that a total of 313 species of higher plants inhabit the valley with a characteristic of moist alpine shrub vegetation. The herbaceous life forms dominate and increase with increasing altitude. The major representations are from the families Asteraceae, rosaceae, Lamiaceae and poaceae, suggesting thereby the alpine meadow nature of the study area. The effect of altitude on species diversity displays a hump-shaped curve which may be attributed to increase in habitat diversity at the median ranges and relatively less habitat diversity at higher altitudes. The anthropogenic pressure at lower altitudes results in low plant diversity towards the bottom of the valley with most of the species being exotic in nature. Though the plant diversity is less at higher altitudinal ranges, the uniqueness is relatively high with high species replacement rates. More than 90 % of variability in the species diversity could be explained using appropriate quantitative and statistical analysis along the altitudinal gradient. The valley harbours 18 threatened and 41 endemic species, most of which occur at higher altitudinal gradients due to habitat specificity.

关键词： plant species diversity threatened species altitudinal gradient flora Bhabha Valley western Himalaya India

Study of cyanide removal from contaminated water using zinc peroxide nanomaterial

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Journal of Environmental Sciences 2017年第5期29卷 76-85页

作者： Himani Uppal S. Swarupa Tripathy Sneha Chawla Bharti Sharma M.k. Dalai S.p. singh Sukhvir singh Nahar singh CSIr-National physical Laboratory New Delhi 110012 India Electronic Science Kurukshetra University Kurukshetra Haryana 136119 India Academy of Scientific and Innovative research (AcSIr) India

The present study highlights the potential application of zinc peroxide （ZnO2） nanomaterial as an efficient material for the decontamination of cyanide from contaminated water. A process patent for ZnO2 synthesis has been granted in United States of America （US patent number 8,715,612; May 2014）, South Africa, Bangladesh, and India. The ZnO2 nanomaterial was capped with polyvinylpyrrolidone （pVp） to control the particle size. The pVp capped ZnO2 nanomaterial （pVp-ZnO2） before and after adsorption of cyanide was characterized by scanning electron microscope, transmission electron microscope, X-ray diffractorneter, Fourier transform infrared spectroscopy and time of flight-secondary ion mass spectrom- etry. The remaining concentration of cyanide after adsorption by pVp-ZnO2 was determined using ion chromatograph. The adsorption of cyanide over pVp-ZnO2 was also studied as a function of pH, adsorbent dose, time and concentration of cyanide. The maximum removal of cyanide was observed in pH range 5.8-7.8 within 15 rain. The adsorption data was fitted to Langmuir and Fruendlich isotherm and it has been observed that data follows both the isotherms and also follows second order kinetics.

关键词： Cyanide Zinc peroxide Adsorption Ion chromatograph

Structural,Transport and Optical properties of Boron-doped Zinc Oxide Nanocrystalline

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Journal of Materials Science & Technology 2011年第6期27卷 481-488页

作者： Vinod kumar r.G.singh L.p.purohit r.M.Mehra Department of physics Gurukula Kangri University Department of Electronic Science University of Delhi South Campus Maharaja Agrasen College University of Delhi 110 096 India School of Engineering & Technology Sharda University

The paper has reported the structural,transport and optical properties of boron doped zinc oxide（ZnO：B） thin films grown on glass substrate by sol-gel spin coating *** is observed from the analysis of the X-ray diffraction（XrD） results that the crystalline quality of the films is improved with increasing B concentration.A crystallite size of ～17 nm is obtained for B doped films.A minimum resistivity of 7.9×10-4 Ω.cm is obtained at 0.6 at.% of B concentration in the ZnO：B *** and intragrain cluster scattering are found to dominate the scattering mechanism in ZnO：B *** interference pattern in transmittance spectra shows good homogeneity with a transparency of ～88% in the visible *** band gap of the films is increased from 3.24 to 3.35 eV with increasing B *** gap widening is analyzed in terms of Burstein-Moss *** origin of the broad band photoluminescence（pL） spectra is explained in terms of the intragrain cluster scattering.

关键词： Zinc oxide Boron photoluminescence Intragrain B-M shift