检索结果-南通市图书馆

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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：泥炭沼泽岩石演化煤场西印度硫酸盐还原造型显微组分样品收集

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

Magnesium oxide(MgO) nanoadsorbents in wastewater treatment: A comprehensiv. rev.ew

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第5期12卷 1709-1773页

作者： H.C.S.Perera v.Gurunanthanan Anoop singh M.M.M.G.P.G.Mantilak. G.Das Sandeep Arya Department of Physics Khalifa University Postgraduate Institute of Science University of Peradeniya Department of Humanities and Sciences Guru Nanak Institutions Technical Campus Centre for Global Health Research Saveetha Medical College and Hospitals Saveetha Institute of Medical and Technical Sciences Department of Physics University of Jammu

Wastewater contamination by heav. metals and synthetic dyes presents a significant env.ronmental challenge, necessitating effectiv. and sustainable separation techniques. This rev.ew article prov.des a detailed examination of magnesium oxide(MgO) nanoparticles as an innov.tiv. nanoadsorbent for wastewater treatment, with a specific focus on heav. metal and dye remov.l. The rev.ew comprehensiv.ly explores v.rious aspects of MgO nanoparticles, including their structural characteristics and synthesis techniques. The article delv.s into the morphology and crystallographic arrangement of MgO nanoparticles, offering insights into their structural attributes. Giv.n the complexity of adsorption processes, the rev.ew identifies and analyzes parameters influencing the adsorption efficiency of MgO nanoparticles, such as temperature, pH, contact time, initial concentration, and co-existing ions. The interplay between these parameters and the adsorption capability of MgO nanoparticles emphasizes the importance of optimizing operational conditions. Furthermore, the rev.ew assesses v.rious synthesis methods for MgO nanoparticles, including sol-gel, hydrothermal, precipitation, green synthesis, solv.thermal, and template-assisted techniques. It discusses the adv.ntages, limitations, and resulting nanoparticle characteristics of each method, enabling readers to grasp the implications of synthesis processes on adsorption efficiency. This comprehensiv. rev.ew consolidates current insights into the effectiv.ness of MgO nanoparticles as a potent nanoadsorbent for remov.ng heav. metals and dyes from wastewater cov.ring a wide spectrum of aspects related to MgO nanoparticles. Moreov.r, there is a need to inv.stigate the use of MgO in the treatment of actual wastewater or riv.r water,in order to lev.rage its cost-effectiv.ness and high efficiency for practical water treatment applications in real-time.

关键词： MgO nanoparticles Nanoadsorbent Wastewater treatment Heav. metals Dye separation Adsorption Synthesis methods

Eocene lignites from Cambay basin, Western India： An excellent source of hydrocarbon

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2016年第5期7卷 811-819页

作者： P.k.singh v.k.singh P.k.Rajak.M.P.singh A.S.Naik.S.v.Raju D.Mohanty Coal & Organic Petrology Lab Centre of Advanced Study in Geology Banaras Hindu University Varanasi 221005 Uttar Pradesh India Research & Dev.lopment Oil India Limited Duliajan Assam 786 602 India Central Institute of Mining and Fuel Research Barwa Road Dhanbad 826015 India

In the present paper lignites from the Cambay basin hav. been studied for their hydrocarbon potential.The samples were collected from three lignite fieldse v.stan, Rajpardi and Tadk.shwar, and were inv.stigated by petrography, chemical analyses and Rock.Ev.l pyrolysis. The results are well comparable with the empirically deriv.d v.lues. The study rev.als that these ‘low rank.C＇ lignites are exceedingly rich in reactiv. macerals（huminite t liptinite） while inertinite occurs in low concentration. These high v.latile lignites generally hav. low ash yield except in few sections. The Rock.Ev.l data indicates the dominance of k.rogen type-III with a little bit of type-II. The study rev.als that the lignites of v.stan（lower and upper seams） and Tadk.shwar upper seam are more gas-prone while Rajpardi and Tadk.shwar lower seams are oil-prone. Further, the fixed hydrocarbons are sev.ral times higher than the free hydrocarbons. The relation between TOC and fixed hydrocarbon indicates that these lignites are excellent source rock.for hydrocarbon which could be obtained mainly through thermal crack.ng. The empirically deriv.d v.lues rev.al a high conv.rsion（94e96%） and high oil yield（64e66%） for these lignites.

关键词： Eocene lignites Cambay basin Rock.Ev.l Maceral Hydrocarbon

In silico Analysis of Sequential,Structural and Functional Div.rsity of Wheat Cystatins and Its Implication in Plant Defense

在线全文

学校读者我要写书评

暂无评论

Genomics, Proteomics & Bioinformatics 2010年第1期8卷 42-56页

作者： Shriparna Dutt v.k. singh Soma S.Marla Anil k.mar Department of Molecular Biology and Genetic Engineering G.B.Pant University of Agriculture and Technology

Phytocystatins constitute a multigene family that regulates the activ.ty of endogenous and/or exogenous cysteine proteinases. Cereal crops lik. wheat are continuously threatened by a multitude of pathogens, therefore cystatins offer to play a piv.tal role in deciding the plant response. In order to study the need of hav.ng div.rse specificities and activ.ties of v.rious cystatins, we conducted comparativ. analysis of six wheat cystatins （WCs） with twelv. rice, sev.n barley, one sorghum and ten corn cystatin sequences employing different bioinformatics tools. The obtained results identified highly conserv.d signature sequences in all the cystatins considered. Sev.ral other motifs were also identified, based on which the sequences could be categorized into groups in congruence with the phylogenetic clustering. Homology modeling of WCs rev.aled 3D structural topology so well shared by other cystatins. Protein-protein interaction of WCs with papain supported the notion that functional div.rsity is a con- sequence of existing differences in amino acid residues in highly conserv.d as well as relativ.ly less conserv.d motifs. Thus there is a significant conserv.tion at the sequential and structural lev.ls; howev.r, concomitant v.riations maintain the functional div.rsity in this protein family, which constantly modulates itself to reciprocate the div.rsity while counteracting the cysteine proteinases.

关键词： wheat cystatins structural div.rsity functional div.rsity comparativ. analysis

Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr M-type hexaferrite nanocrystals

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil M.Patange P.M.Dighe Sher singh Meena Abdullah GAl-Sehemi Mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri v.k.e Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Div.sion Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to inv.stigate the structure-sensitiv. magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=0.05.The hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared spectroscopy.The creation of the M-type hexaferrite phase within the synthesized samples was rev.aled from the Rietv.ld refinement of the X-ray diffractograms.The occurrence of a secondary phase of CeO_(2) was rev.aled within the hexaferrites for the substitution,x> 0.The refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter ratio.The crystal structure plotted from the refined XRD data rev.als the occupancy of the ions at different lattice sites.The XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent elements.The nanocrystalline nature of the hexaferrites was rev.aled from the crystallite sizes calculated using Scherer's formula.The analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) phase.The morphology of the hexaferrites was analyzed from the FESEM profiles of the ferrite samples.The magnetic behav.or study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,v.S.M,and Mossbauer spectroscopy,respectiv.ly.The hexaferrites with increasing coerciv.ty,decreasing saturation magnetization,and decreasing Curie temperature are reported in the study.The substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giv.ng rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coerciv.ty M?ssbauer spectroscopy

EDFA Gain-Flattening Using Side-Polished Fiber Half-Coupler With an Ov.rlay Wav.guide

在线全文

学校读者我要写书评

暂无评论

光学学报 2003年第S1期23卷 243-244页

作者： R.k. v.rshney v.k. singh k. Pande M.R. Shenoy B.P. Pal k. Thyagarajan Department of Physics Indian Institute of Technology Delhi New Delhi 110016 India.Department of Physics Indian Institute of Technology Delhi New Delhi 110016 India.Department of Physics Indian Institute of Technology Delhi New Delhi 110016 India.Department of Physics Indian Institute of Technology Delhi New Delhi 110016 India.Department of Physics Indian Institute of Technology Delhi New Delhi 110016 India.Department of Physics Indian Institute of Technology Delhi New Delhi 110016 India.

We report fabrication and modeling of a fiber half-coupler based gain-flattening dev.ce for EDFA. Using such a dev.ce, flattening of the ASE spectrum of an EDFA is also demonstrated.

关键词： EDFA Gain-Flattening Using Side-Polished Fiber Half-Coupler With an Ov.rlay Wav.guide of in de for ASE SPF been