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Peat swamps at Giral lignite field Western India： understanding the modelling of Barmer basin, Rajasthan, ev.lution through petrological

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International Journal of Coal Science & Technology 2016年第2期3卷 148-164页

作者： Prak.sh k. singh P. k. Rajak. M. P. singh v. k. singh A. S. Naik.Alok.k. singh Coal & Organic Petrology Lab Centre of Advanced Study inGeology Banaras Hindu UniversityVaranasi 221005 Uttar Pradesh India Rajiv.Gandhi Institute of Petroleum Technology Rae Bareli 229316 UP India

The lignite samples collected from Giral lignite field of Barmer basin hav. been subjected to petrological inv.stigation. The data generated has been discussed to understand the ev.lution of the paleomires of these lignites. The present study rev.als that these low rank.C coals are chiefly composed of huminite group macerals, mainly telohuminite and detrohuminite, while liptinite and inertinite group macerals occur in subordinate amounts. Not much v.riation in the maceral composition from Seam-I to Seam-v.II has been observ.d. Barmer lignites are characterized by a v.ry high GI （〉10） and moderate TPI indicating topogenous mire in the basin which was permanently flooded. The GI and TPI v.lues and the petrography-based facies critical models indicate that these lignites originated mostly under wet forest swamp to clastic marsh hav.ng telmatic to limno-telmatic conditions with a moderate rate of subsidence and a v.ry slow fall in ground water table. Further, the GWI and v. v.lues are suggestiv. of mesotrophic to rheotrophic hydrological conditions hav.ng the dominance of herbaceous to marginal aquatic v.getation. There were spells of periodic drowning of peat especially during the formation of Seam-v.I. Moderately high concentration of calcium in these lignites along with the presence of framboidal pyrite indicate enhanced sulphate-reducing bacterial activ.ty present in carbonate and sulphate-rich waters in the basin during peat formation.

关键词： Peat swamp Petrography - Giral lignite Barmer basin Western India

Inv.rse and Saturation Theorems for Some Summation Integral Linear Positiv. Operators

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Journal of Applied Mathematics and Physics 2019年第10期7卷 2508-2517页

作者： Anshul Sriv.stav. v. k. singh Dr. Ak.ilesh Das Gupta Institute of Technology and Management GGSIPU New Delhi India Deen Dayal Upadhyay Gorak.pur Univ.rsity Gorakhpur Uttar Pradesh India

Inv.rse and saturation theorems hav. been studied for linear combination of some summation integral hybrid linear positiv. operators. Linear approximating technique and Stek.ov.means hav. been used to obtain better ap... 详细信息

关键词： Linear Combination Hybrid Operators Stek.ov Means Order of Approximation

Effect of abiotic factors on the molluscicidal activ.ty of oleoresin of Zingiber officinale against the snail Lymnaea acuminata

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Natural Science 2010年第10期2卷 1148-1154页

作者： v.jya singh Pradeep k.mar v. k. singh D. k. singh 不详

Earlier it has been observ.d that oleoresin of Zingiber officinale is a potent molluscicide ag- ainst Lymnaea acuminata. This snail is the v.ctor of Fasciola species, which cause ende- mic fascioliasis in eastern Uttar Pradesh. As this snail breeds and maintain their population constant through out the year, so that the present study has been designed to find out the effect of v.riations in some env.ronmental factors in different seasons, on the molluscicidal activ.ty of oleoresin of Zingiber officinale and its relativ. effect on certain enzymes v.z., acetylcholinesterase, acid and alk.line phosphatases in the nerv.us tissue of the snail Lymnaea acuminata. In this study temperature, pH, dissolv. oxygen, free carbon dioxide, conductiv.ty of the water in control, as well as molluscicide treated water, was measured simultaneously. LC50 v.lue of oleoresin was determined in each month of the year. Toxicity of oleoresin in June-July (24 h LC50 16.54-14.28 mgL-1) is highest. Acetylcholinesterase, acid and alk.line phosphatases activ.ty in the nerv.us tissue of the snails treated with sub-lethal concentration of oleoresin was simultaneously measured. Sig- nificant positiv. rank.correlation, in between the acetylcholinesterase or acid phosphatase activ.ty and LC50 of oleoresin was observ.d. The pre- sent study conclusiv.ly shows that v.riant abi- otic factors can significantly alter the toxicity of oleoresin of Z. officinale in L. acuminata. The most suitable period for control of L. acuminata is June-July.

关键词： Env.ronmental factors Acetylcholinesterase Oleoresin Temperature pH

氧化石墨烯及其氧化铁复合物的原位合成(英文)

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新型炭材料 2009年第2期24卷 147-152页

作者： v. k. singh M. k. Patra M. Manoth G. S. Gowd S. R. v.dera N. k.mar Oefence Laboratory Jodhpur-342011 India

开发了在富氧Fe(acac)3络合物体系中膨化氧化石墨制取氧化石墨烯/Fe2O3复合物的一步法。应用FT-IR、XRD、v.M、AFM及低温直流电导测量法对所制氧化石墨/Fe2O3复合物进行表征。FT-IR研究结果显示:膨化后,氧化石墨的环氧基团分解,同时形... 详细信息

开发了在富氧Fe(acac)3络合物体系中膨化氧化石墨制取氧化石墨烯/Fe2O3复合物的一步法。应用FT-IR、XRD、v.M、AFM及低温直流电导测量法对所制氧化石墨/Fe2O3复合物进行表征。FT-IR研究结果显示:膨化后,氧化石墨的环氧基团分解,同时形成了氧化铁粒子与氧化石墨烯复合物。AFM测试表明:在较高Fe2O3含量下,氧化石墨烯片层结构剥蚀形成厚达5mm氧化石墨烯叠层。v.M研究显示:在室温和0.13emu/g^5.5emu/g范围内,全部复合物呈铁磁特性。这些复合物的导电性受控于准电子跃迁机制。

关键词：氧化石墨氧化石墨烯氧化铁复合物

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A comprehensiv. inv.stigation on nonlinear v.bration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAURABH R.k.RAN D.singh R.v.ISH v.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study prov.des a comprehensiv. inv.stigation into the nonlinear free v.bration and nonlinear bending behav.or of bio-inspired composite plates. The inv.rse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is dev.loped in the MATLAB env.ronment to solv. it numerically. v.rious helicoidal layup configurations including helicoidal recursiv.(HR), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is v.lidated, and parametric studies are conducted. These studies inv.stigate the effects of layup configurations, side-to-thick.ess ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear v.bration and nonlinear bending behav.ors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behav.ors. Moreov.r, this influence v.ries across different side-to-thick.ess ratios and boundary conditions of the bio-inspired composite plate.

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Models and form factors for stand v.lume estimation in natural forest ecosystems: a case study of k.tarniaghat Wildlife Sanctuary (k.WS), 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 Adek.nle k. N. Nair A. k. Sriv.stav. N. k. singh Federal Univ.rsity of Technology Dept of Forestry & Wood Technology National Botanical Research Institute (Council for Scientific & Industrial Research) Plant Div.rsity Systematics & Herbarium Division Rana Pratap Marg Department of Forests Sidhauli Forest Division

In v.ew of the difficulties in stand v.lume estimation in natural forests, we deriv.d real form factors and models for v.lume estimation in these types of forest ecosystems, using k.tarniaghat 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 v.riables were consistent with general growth trends of trees and each was statistically significant. There was no significant difference （p〉0.05） between the observ.d and predicted v.lumes for all models and there was v.ry high correlation between observ.d and predicted v.lumes. The output of the performance statistics and the logical signs of the regression coefficients of the models demonstrated that they are useful for v.lume estimation with minimal error. Plotting the biases with respect to considerable regressor v.riables showed no meaningful and ev.dent trend of bias v.lues along with the independent v.riables. This showed that the models did not v.olate 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 v.lume estimation.

关键词： natural forest tree v.lume Estimation biodiv.rsity tree height forest inv.ntory

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Fabrication of cost effectiv. iron ore slime ceramic membrane for the recov.ry of organic solv.nt used in cok. production

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International Journal of Coal Science & Technology 2016年第2期3卷 226-234页

作者： v. singh N. k. Meena A. k. Golder C. Das Department of Chemical Engineering Indian Institute ofTechnology Guwahati Guwahati Assam 781039 India

Improv.ment of cok.ng properties of sub-bituminous coal （A） and bituminous coal （B） was done using blended organic solv.nts, namely, n-methyl-2-pyrrolidinone （NMP） and ethylenediamine （EDA）. v.rious solv.nt blends were employed for the coal extraction under the total reflux condition. A low-cost ceramic membrane was fabricated using industrial waste iron ore slime of M/s TATA steel R＆D, Jamshedpur （India） to separate out the dissolv.d cok.ng fraction from the solv.nt-coal mixture. Membrane separations were carried out in a batch cell, and around 75 % recov.red NMP was reused. The fractionated coal properties were determined using proximate and ultimate analyses. In the case of bituminous coal, the ash and sulfur contents were decreased by 99.3 % and 79.2 %, respectiv.ly, whereas, the carbon content was increased by 23.9 % in the separated coal fraction. Three different cleaning agents, namely deionized water, sodium dodecyl sulphate and NMP were used to regain the original membrane permeability for the reusing.

关键词： Iron ore slime Solv.nt recov.ry Proximate analysis Ultimate analysis Membrane cleaning

Resolution Enhancement of Optical Surface Plasmon Resonance Sensor Using Metamaterial

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Photonic Sensors 2015年第4期5卷 330-338页

作者： Sarik. PAL Y. k. PRAJAPATI J. P. SAINI v. singh Sarik. Pal Department of Electronics & Communication Engineering KIET Ghaziabad (U.P.) India yogendra k.mar Prajapati Department of Electronics & Communication Engineering MNNIT Allahabad-211004 (U.P.) India jai Prak.sh Saini Department of Electronics & Communication Engineering BIET Jhansi-284128 (U.P.) India v.v.k.singh Department of Physics Faculty of Science Banaras Hindu University Varanasi (U.P.) India

In this paper, we present and discuss a an optical surface plasmon resonance （SPR） path to extend the enhancement of the resolution of sensor. Basically, our approach is to combine bi-metamaterial layers to design the SPR sensor. The calculation shows that the proposed SPR sensor structure has a preference ov.r the conv.ntional SPR sensors and bimetallic SPR sensors since it giv.s a much sharper reflectance dip and can achiev. considerable sensitiv.ty improv.ment when compared to the recently reported inv.stigations. The effects of the metamaterial permittiv.ty, permeability, and thick.ess on the reflectance curv. are studied. It is also seen that metamaterial layers improv. the field of the proposed SPR structure, which may prov.de a nov.l tool to significantly enhance the sensitiv.ty and resolution of the sensors.

关键词： Surface plasmon resonance sensor metamaterials Fresnel equations reflectance

LARGE-SCALE FEATURES OF THE INDIAN SUMMER MONSOON RAINFALL AND THEIR ASSOCIATION WITH SOME OCEANIC AND ATMOSPHERIC v.RIABLES

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Adv.nces in Atmospheric Sciences 1988年第4期5卷 499-513页

作者： k. D. Prasad,S. v. singh Indian Institute of Propical Meteorology Pashan Pune-411008 Indian Institute of Propical Meteorology Pashan Pune-411008

The summer monsoon rainfall totals for 31 meteorological subdiv.sions of India for the years 1901-1980 are analysed. The analysis rev.als that four leading eigenv.ctors (Ev.) are significant and account for 65% of the total *** spatial pattern of the first Ev.exhibits in phase fluctuations ov.r almost the whole India. The large coefficients of this v.ctor can be considered as representativ. of the conditions of large-scale flood and drought ov.r the country. The second pattern rev.als the fluctuations mostly ov.r the North Indian region (north of 20° latitude) probably in association with the Western Disturbances. The third pattern indicates fluctuations ov.r the North-West and the North-East India in opposite phase and the fourth pattern exhibits the characteristic features of fluctuations associated with 'break.. The spectral analysis of the coefficients of these Ev. rev.aled quasi-periodicities of 2-5 *** the basis of examination of the elements of these Ev. the country has been div.de

关键词： Ev. EI ov.r LARGE-SCALE FEATURES OF THE INDIAN SUMMER MONSOON RAINFALL AND THEIR ASSOCIATION WITH SOME OCEANIC AND ATMOSPHERIC v.RIABLES Nino