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Acta Geochimica 2022年第1期41卷 100-120页

作者： Roshmi Boruah Jayanta Jivan Laskar Department of Geological Sciences Gauhati UniversityGuwahatiAssam 781014India

Sandstones from the Neogene Siwalik successions of the East and West Siang Districts of Arunachal Pradesh were analyzed to evaluate source-area weathering,provenance,and tectonic setting by using major,trace,and rare earth elements(REEs)as *** sandstones are classified as lithic arenite and wacke arenite based on their mineralogical *** values of different weathering indices such as Chemical Index of Alteration(CIA;60.93–89.86)and Chemical Index of Weathering(CIW;40–96.8)suggest moderate to intense weathering in the source *** plot of Th/Sc versus Zr/Sc indicates enrichment of zircon by sediment sorting and/or recycling from a weathered *** high positive correlation between Al2 O_(3) and K2 O points towards a strong influence of the constituent clay minerals on the major oxide composition of the *** analysis together with enriched LREE,flat HREE,negative Eu anomalies(Eu/Eu^(*)=0.47 to 0.90)in the chondrite-normalized diagrams,and the ratios of La/Sc,La/Co,Th/Sc,Th/Co,Cr/Th collectively suggests that the Neogene sediments were derived from felsic igneous and/or reworked sedimentary/metasedimentary sources in an upper continental crustal *** geochemical characteristics of the studied Neogene Siwalik sandstones indicate that the sediments were sourced from pre-Himalayan gneisses and granitoids together with metabasic rocks,which had formed in a passive margin tectonic setup.

关键词： Geochemistry Neogene sandstones Arunachal Pradesh Paleo-weathering Provenance Tectonic setting

Morphological parameters and genetic diversity of progenies from seed production areas and unimproved stands of teak(Tectona grandis L.f.)in India

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Journal of Forestry research 2013年第4期24卷 653-658页

作者： N.Lyngdoh Geeta Joshi G.Ravikanth R.Vasudeva R.Uma Shaanker Tree Improvement and Propagation Division Institute of Wood Sciences and Technology 18th Cross MalleswaramBangalore School of Ecology and Conservation University of Agricultural Sciences Banga- lore 560065India Ashoka Trust for research in Ecology and the Environment Royal Enclave SrirampuraJakkur PostBangalore- 560064India Department of Forest Biology and Tree Improvement College of Forestry Sirsi581401KarnatakaIndia Department of Crop Physiology University of Agricultural Sciences Bangalore 560065India

We compared morphological and genetic attributes of prog- eny obtained from three seed production areas （SPAs） and three corre- sponding unimproved stands （UIS） of teak （Tectona grandis L.f） at three broad teak growing regions in the state of Karnataka, India. In general, seed morphological parameters such as seed weight, seed size and seed emptiness were significantly superior in SPAs compared to UISs. Seed germination percentage was also higher in seeds from SPAs. Seedling performance measured at two monthly intervals for six months was ob- served to be superior in SPAs at two of the three regions compared. Although the genetic diversity of progeny of SPAs was lower than UIS at all regions, the values were moderately high. Germination percent was positively correlated with fruit weight and kernel weight per seed, while diversity indices were negatively correlated with fruit weight, fruit di- ameter and kernel weight per seed. SPAs proved important as a source of moderately improved planting material with no severe threat to the ge- netic diversity of future plantations.

关键词： ISSR tree improvement Shannon index teak plantations percent polymorphism

A Study of the Number of Roots of xk =g in a Finite Group via Its Frobenius-Schur Indicators

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Algebra Colloquium 2017年第1期24卷 93-108页

作者： S.K. Prajapati R. Sarma Department of Mathematics Indian Institute of Technology Delhi Hauz Khas New Delhi 110016 India

Let G be a finite group. For k ∈ N, X ∈ Irr（G）, define c（k）x ：= 1/G ∑g∈G x（gk）. This is called the k-th Frobenius-Schur indicator of X. In this article we study the Probenius-Schur indicators for Frobenius groups, p-groups, semidihedral groups and mod- ular p-groups. Further, we use this to study the function ζ kG（g） which counts the number of roots of xk = g in a finite group G.

关键词： Frobenius-Schur indicators p-groups group characters

Models and form factors for stand volume estimation in natural forest ecosystems: a case study of Katarniaghat Wildlife Sanctuary (KGWS), Bahraich District, India

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Journal of Forestry research 2013年第2期24卷 217-226页

作者： V. A. J Adekunle K. N. Nair A. K. Srivastava N. K. Singh Federal University of Technology Dept of Forestry & Wood Technology National Botanical research Institute (council for scientific & industrial research) Plant Diversity Systematics & Herbarium Division Rana Pratap Marg Department of Forests Sidhauli Forest Division

In view of the difficulties in stand volume estimation in natural forests, we derived real form factors and models for volume estimation in these types of forest ecosystems, using Katarniaghat Wildlife Sanctuary as a case study. Tree growth data were obtained for all trees （dbh 〉10 cm） in 4 plots （25 × 25 m） randomly located in each of three strata selected in the forest. The form factor calculated for the stand was 0.42 and a range of 0.42 0.57 was estimated for selected species （density 〉10）. The parameters of model variables were consistent with general growth trends of trees and each was statistically significant. There was no significant difference （p〉0.05） between the observed and predicted volumes for all models and there was very high correlation between observed and predicted volumes. The output of the performance statistics and the logical signs of the regression coefficients of the models demonstrated that they are useful for volume estimation with minimal error. Plotting the biases with respect to considerable regressor variables showed no meaningful and evident trend of bias values along with the independent variables. This showed that the models did not violate regression assumptions and there were no heteroscedacity or multiculnarity problems. We recommend use of the form factors and models in this ecosystem and in similar ones for stand and tree volume estimation.

关键词： natural forest tree volume Estimation biodiversity tree height forest inventory

Effect of relaxation times on circular crested waves in thermoelastic diffusive plate

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Applied Mathematics and Mechanics(English Edition) 2010年第4期31卷 493-500页

作者： Rajneesh KUMAR Tarun KANSAL Department of Mathematics Kurukshetra University

The propagation of circularly crested thermoelastic diffusive waves in an infinite homogeneous transversely isotropic plate subjected to stress free, isothermal/insulated and chemical potential conditions is investigated in the framework of different thermo- elastic diffusion theories. The dispersion equations of thermoelastic diffusive Lamb type waves are derived. Some special cases of the dispersion equations are also deduced.

关键词： wave propagation transversely generalized thermoelastic diffusion attenuation isotropic crested waves phase velocity coefficient amplitudes

Numerical study of flow and heat transfer during oscillatory blood flow in diseased arteries in presence of magnetic fields

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Applied Mathematics and Mechanics(English Edition) 2012年第5期33卷 649-662页

作者： A.SINHA J.C.MISRA School of Medical Science and Technology Indian Institute of TechnologyKharagpur 721302India Department of Mathematics Institute of Technical Education and ResearchSiksha O Anusandhan UniversityBhubaneswar 751030India

A problem motivated by the investigation of the heat and mass transfer in the unsteady magnetohydrodynamic （MHD） flow of blood through a vessel is solved numerically when the lumen of the vessel has turned into the porous structure. The time-dependent permeability and the oscillatory suction velocity are considered. The computational results are presented graphically for the velocity, the temperature, and the concentration fields for various values of skin friction coefficients, Nusselt numbers, and Sherwood numbers. The study reveals that the flow is appreciably influenced by the presence of a magnetic field and also by the value of the Grashof number.

关键词： mass transfer radiation suction velocity skin-friction

Radiation effect on temperature distribution in three-dimensional Couette flow with suction or injection

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Applied Mathematics and Mechanics(English Edition) 2007年第3期28卷 309-316页

作者： Bhupendra Kumar Sharma Mamta Agarwal R.C.Chaudhary Department of Mathematics University of RajasthanJaipur-302004India

A theoretical analysis of three-dimensional Couette flow with radiation effect on temperature distribution has been analysed, when the injection of the fluid at the lower stationary plate is a transverse sinusoidat one and its corresponding removal by constant suction through the upper porous plate is in uniform motion. Due to this type of injection velocity, the flow becomes three-dimensional. The effect of Prandtl number, radiation parameter and injection parameter on rate of heat transfer has been examined by the help of graphs. The Prandtl number has a much greater effect on *** distribution than the injection or radiation parameter.

关键词： Couette flow three-dimensional heat transfer radiation incompressible

Electrochemical Impedance Analysis of Biofunctionalized Conducting Polymer-Modified Graphene-CNTs Nanocomposite for Protein Detection

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Nano-Micro Letters 2017年第1期9卷 104-112页

作者： Shobhita Singal Avanish K.Srivastava Rajesh CSIR-National Physical Laboratory Dr.K.S.Krishnan RoadNew Delhi 110012India Academy of scientific and Innovative research(AcSIR) CSIR-National Physical LaboratoryDr.K.S.Krishnan RoadNew Delhi 110012India

We report an electrodeposited poly(pyrrole-co-pyrrolepropylic acid) copolymer modified electroactive graphene-carbon nanotubes composite deposited on a glassy carbon electrode to detect the protein antigen(cTnI). The copolymer provides pendant carboxyl groups for the site-specific covalent immobilization of protein antibody, antitroponin I. The hybrid nanocomposite was used as a transducer for biointerfacial impedance sensing for cTnI *** results show that the hybrid exhibits a pseudo capacitive behaviour with a maximum phase angle of 49° near 1 Hz,which is due to the inhomogeneous and porous structure of the hybrid composition. The constant phase element of copolymer is 0.61(n = 0.61), whereas, it is 0.88(n = 0.88) for the hybrid composites, indicating a comparatively homogeneous microstructure after biomolecular functionalization. The transducer shows a linear change in charge transfer characteristic(R_(et)) on cTnI immunoreaction for spiked human serum in the concentration range of 1.0 pg mL^(-1)–10.0 ng mL^(-1). The sensitivity of the transducer is 167.8 ± 14.2 Ω cm^2 per decade, and it also exhibits high specificity and good reproducibility.

关键词： Conducting polymer Graphene Carbon nanotube Hybrid Transducer Protein antigen cTnI Electrochemical impedance

Response of loose bonding on reflection and transmission of elastic waves at interface between elastic solid and micropolar porous cubic crystal

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Applied Mathematics and Mechanics(English Edition) 2010年第5期31卷 605-616页

作者： Rajneesh KUMAR Meenakshi PANCHAL Department of Mathematics Kurukshetra University

The problem of reflection and transmission of plane periodic waves incident on the interface between the loosely bonded elastic solid and micropolar porous cubic crystal half spaces is investigated. This is done by assuming that the interface behaves like a dislocation, which preserves the continuity of traction while allowing a finite amount of slip. Amplitude ratios of various reflected and transmitted waves have been depicted graphically. Some special cases of interest have been deduced from the present investigation.

关键词： micropolar porous cubic crystal reflection coefficients transmission coefficients bonding parameter

Uncertainty of soil erosion modelling using open source high resolution and aggregated DEMs

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Geoscience Frontiers 2017年第3期8卷 425-436页

作者： Arun Mondal Deepak Khare Sananda Kundu Sandip Mukherjee Anirban Mukhopadhyay Surajit Mondal Department of Water Resources Development & Management Indian Institute of Technology Roorkee India Department of Natural Resources TERI University New Delhi 110 070 India School of Oceanographic Studies Jadavpur University Kolkata India d Division of Land Division of Land & Water Management Research Complex for Eastern Region(RCER)Indian Council of Agricultural Research(ICAR) Patna India

Digital Elevation Model （DEM） is one of the important parameters for soil erosion assessment. Notable uncertainties are observed in this study while using three high resolution open source DEMs. The Revised Universal Soil Loss Equation （RUSLE） model has been applied to analysis the assessment of soil erosion uncertainty using open source DEMs （SRTM, ASTER and CARTOSAT） and their increasing grid space （pixel size） from the actual. The study area is a part of the Narmada river basin in Madhya Pradesh state, which is located in the central part of India and the area covered 20,558 km2. The actual resolution of DEMs is 30 m and their increasing grid spaces are taken as 90, 150, 210, 270 and 330 m for this study. Vertical accuracy of DEMs has been assessed using actual heights of the sample points that have been taken considering planimetric survey based map （toposheet）. Elevations of DEMs are converted to the same vertical datum from WGS 84 to MSL （Mean Sea Level）, before the accuracy assessment and modelling. Results indicate that the accuracy of the SRTM DEM with the RMSE of 13.31, 14.51, and 18.19 m in 30, 150 and 330 m resolution respectively, is better than the ASTER and the CARTOSAT DEMs. When the grid space of the DEMs increases, the accuracy of the elevation and calculated soil erosion decreases. This study presents a potential uncertainty introduced by open source high resolution DEMs in the accuracy of the soil erosion assessment models. The research provides an analysis of errors in selecting DEMs using the original and increased grid space for soil erosion modelling.

关键词： DEM RUSLE SRTM ASTER CARTOSAT