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Petrogenesis of shoshonitic granitoids,eastern India:Implications for the late Grenvillian post-collisional magmatism

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Geoscience Frontiers 2014年第6期5卷 821-843页

作者： b.Goswami c.bhattacharyya Department of Geology University of Calcutta35 Ballygunge Circular RoadKolkata 700 019India

Many elongated, lenticular plutons of porphyritic granitoids are distributed mainly near the southern and northern margin of the chhotanagpur Gneissic complex （cGc） which belongs to the EW to ENE-WSW tending 1500 km long Proterozoic orogenic belt amalgamat ng the North and South Indian cratonic blocks. The late Grenvillian （1071 ±64 Ma） Raghunathpur porphyritic granitoid gneiss （PGG） batholith comprising alkali feldspar granite, granite, granodiorite, tonalite, quartz syenite and quartz monzonite intruded into the granitoid gneisses of southeastern part of cGc in the Purulia district, West bengal and is aligned with ENE-WSW trending North Purulia sr^ear zone, Mineral chemistry, geochemistry, physical condition of crystallization and petrogenetic model of Raghunathpur PGG have been discussed for the first time. The petrographic and geochemical features （including major and trace- elements, mineral chemistry and S7Sr/S6Sr ratio） suggest these granitoids to be classified as the shosh- onitic type. Raghunathpur batholith was emplaced at around 800 ~c and at 6 kbar pressure tectonic discrimination diagrams reveal a post-collision tectonic setting while structural studies reveal its emplacement in the extensional fissure of North Purulia shear zone. l＇he Raghunathpur granitoid is compared with some similar granitoids of Europe and china to draw its petrogenetic model. Hybridi- zation of mantle-generated enriched mafic magma and crustal magma at lower crust and later fractional crystallization is proposed for the petrogenesis of this PGG. Mafic magma generated in a post-collisional extension possibly because of delamination of subducting slab. Raghunathpur batholith had emplaced in the cGc during the final amalgamation （~ 1.0 Ga） of the North and South Indian cratonic blocks. Granitoid magma, after its generation at depth, was transported to its present level along megadyke channel, ways within shear zones.

关键词： Granitoids Petrology Geochemistry Shoshonitic Post-collisiooal chhotanagpur Gneissic complex

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Soils and Surface Waters as Affected by Long-Term Swine Slurry Application in Oxisols of Southern brazil

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Pedosphere 2014年第5期24卷 585-594页

作者： T.bROETTO c.G.TORNQUIST c.bAYER b.c.cAMPOS c.G.MERTEN b.WOTTRIcH Departamento de Solos Universidade Federal do Rio Grande do Sul (UFRGS) 91540-000 Porto Alegre RS (Brazil) Instituto Federal do Rio Grande do Sul/campus Ibirubá

The accelerated expansion of swine production in brazil has increased the generation of liquid wastes, which are usually applied to agricultural soils after a simplified treatment and pose potential environmental impacts. The objective of this study was to assess the agronomic and environmental impacts of long-term application of swine slurry(SS) on soil and stream water properties in watersheds dominated by Oxisols in Quinze de Novembro of Southern brazil. Soil samples(0–30 cm) were collected from farms with continuous application of SS since 1990 at low(40–80 m3 SS ha-1year-1) and high(120–300 m3 SS ha-1year-1) rates of SS. Surface water samples were collected from streams adjacent to the farm fields. Long-term SS application did not change total organic c and particulate organic c compared to cropland and woodland soils without SS application. The high rates of SS increased total N, P, cu,and Zn and available P and cu in the topsoil(0–10 cm) compared to woodland and cropland soils without SS application. Surface water analyses showed that fecal coliform bacteria and biological oxygen demand exceeded the legal limits for high quality water(class 1). Other water parameters(such as NO-3, phosphate and total suspended solids) were within the acceptable limits. Long-term disposal of SS in cropland under no-tillage had impaired water quality in Quinze de Novembro, especially biological parameters. Some best management practices should be adopted, including more rigorous control of SS application to cropland as well as requiring edge-of-field and riparian vegetative buffers.

关键词： no-tillage nutrient balance swine farm water quality watershed

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chemical forms and extractability of iron in sediments of three contrasting lakes of china and UK

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Journal of Environmental Sciences 2003年第6期15卷 728-733页

作者： Gibson c.E.,Stewart b.M. Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology chinese Academy of Sciences Department of Agricultural and Environmental Science Queen's University belfast Shenyang 110016 china Newforge Lane belfast bT9 5PX UK

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. Extractability of iron in sediments of West Lake and Taihu Lake in china and Lower Lough Erne in Northern Ireland of UK was comparatively investigated on the basis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active" iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L Hcl DTPA+TEA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L Mgcl 2 = 0.5 mol/L cacl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. Extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments.

关键词： iron chemical form extractability lake sediment eutrophication

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An analytical model for electrode-ceramic interaction in multilayer piezoelectric actuators

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Acta Mechanica Sinica 2007年第2期23卷 199-208页

作者： b.L.Wang J.c.Han center for composite Materials Harbin Institute of TechnologyHarbin 150001China

The present paper develops an analytical model for multi-electrodes in multi-layered piezoelectric actuators, in which the electrodes are vertical to and terminated at the edges of the medium and electroelastic field concentrations ahead of the electrodes in the multilayer piezoelectric actuators are examined. by considering a representative unit in realistic multilayers, the problem is formulated in terms of electric potential between the electrode tips and results in a system of singular integral equations in which the electric potential is taken as unknown function. Effects are investigated of electrode spacing and piezoelectric coupling on the singular electroelastic fields at the electrode tips, and closed-form expressions are given for the electromechanical field near the electrode tips. Exact solution for un-coupled dielectrics is provided, where no piezoelectric coupling is present.

关键词： Actuators . Piezoelectric materials . Electrodes. Multilayer. Fracture mechanics

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Investigation on Precipitation Transition in cGHAZ for TRIP Steels containing Vanadium and Titanium

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Journal of Iron and Steel Research International 2011年第S1期18卷 154-158页

作者： cooman De b c Graduate Institute for Ferrous Technology Pohang University of Science and TechnologyPohangSouth Korea

Two kinds of low-carbon low-silicon TRIP (Transformation Induced Plasticity) steels containing vanadium are designed using Thermocalc software in the light of both thermodynamics and *** heat treatment process of different steels is determined according to the calculation results *** HAZ (Heat-Affected Zone) simulation tests indicate the weldability of TRIP steels is crucially sensitive to cE (carban equivelent) of the *** the impact toughness of cGHAZ (coarse Grain Heat-Affected Zone) does not decrease drastically for TRIP steels microalloyed with Ti+*** steel containing both of vanadium and titanium shows smaller grain size compared with that containing vanadium *** is because the precipitation of Ti/V carbonitride slows down the grain boundary motion speed and then retards the grain size coalescence in cGHAZ.

关键词： TRIP steel precipitation transition heat-affected zone cGHAZ simulation

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Optimization of Machining characteristics for Al/Sicp composites using ANN/GA

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Journal of Materials Science & Technology 2002年第1期18卷 47-50页

作者： R.Karthikeyan b.c.Pai 等 DepartmentofProductionEngineering AnnamalaiUniversityAnnamalainagar-608002India RegionalResearchLaboratory ThiruvananthapuramIndia

The present work is focused on optimization of machining characteristics of AI/Sicp composites. The machining characteristics such as specific energy, tool wear and surface roughness were studied. The parameters such as volume fraction of Sic, cutting speed and feed rate were considered. Artificial neural networks (ANN) was used to train and simulate the experimental data. Genetic algorithms (GA) was interfaced with ANN to optimize the machining conditions for the desired machining characteristics. Validation of optimized results was also performed by confirmation experiments.

关键词： Al/Sicp composites Artificial neural networks Genetic algorithms

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comparative Effect of an Addition of a Surface Term to Woods-Saxon Potential on Thermodynamics of a Nucleon

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communications in Theoretical Physics 2018年第1期69卷 23-27页

作者： b.c.Lütfüoglu Department of Physics Akdeniz University

In this study, we reveal the difference between Woods-Saxon(WS) and Generalized Symmetric WoodsSaxon(GSWS) potentials in order to describe the physical properties of a nucleon, by means of solving Schr¨odinger equation for the two potentials. The additional term squeezes the WS potential well, which leads an upward shift in the spectrum, resulting in a more realistic picture. The resulting GSWS potential does not merely accommodate extra quasi bound states, but also has modified bound state spectrum. As an application, we apply the formalism to a real problem,an α particle confined in bohrium-270 nucleus. The thermodynamic functions Helmholtz energy, entropy, internal energy,specific heat of the system are calculated and compared for both wells. The internal energy and the specific heat capacity increase as a result of upward shift in the spectrum. The shift of the Helmholtz free energy is a direct consequence of the shift of the spectrum. The entropy decreases because of a decrement in the number of available states.

关键词： Woods-Saxon potential generalized symmetric Woods-Saxon potential bound states analytical solutions partition function thermodynamic functions

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Synthesis and characterization of caAl_xO_y:Eu^(2+) phosphors prepared using solution-combustion method

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Journal of Rare Earths 2010年第S1期28卷 272-276页

作者： F.b.Dejene D.b.bem H.c.Swart Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba9866South Africa Department of Physics University of the Free StateP.O.Box 339Bloemfontein9300South Africa

Europium-doped calcium aluminate(caAlxOy:Eu2+) phosphors were obtained at low temperatures(500 oc) by the solution-combustion of corresponding metal nitrate-urea solution *** particle size and morphology and the structural and luminescent properties of the as-synthesized phosphors were examined by means of scanning electron microscopy(SEM),X-ray diffraction(XRD),Auger spectroscopy,transmission electron spectroscopy(TEM) and photoluminescence(PL).It was found that the ca:Al molar ratios showed greatly influence not only on the particle size and morphology,but also on their PL spectra and *** the ca:Al molar ratios increasing from 6:100 to 26:100,the structure of as-synthesized phosphor changed from caAl12O19 to monoclinic caAl2O4 and the dominant emitting light from red to blue,implying that the oxidation state of doped europium ions changed from trivalent to divalent due to the structure variation of host lattice.A blue phosphor with almost pure phase can be easily prepared by solution combustion method with suitable ca:Al molar ratio.

关键词： caAlxOy:Eu2+ solution-combustion molar ratio structure luminescence rare earths

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A Novel Method for Node connectivity with Adaptive Dragonfly Algorithm and Graph-based m-connection Establishment in MANET

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computers, Materials & continua 2020年第11期65卷 1649-1670页

作者： S.b.Manoojkumaar c.Poongodi Department of computer Science and Engineering J.K.K.Munirajah College of TechnologyGobichettipalayamErode638506India Department of Electronics and communication Engineering Bannari Amman Institute of TechnologySathyamangalamErode638401India

Maximizing network lifetime is measured as the primary issue in Mobile Ad-hoc Networks(MANETs).In geographically routing based models,packet transmission seems to be more appropriate in dense *** involvement of the Heuristic model directly is not appropriate to offer an effectual solution as it becomes NP-hard issues;therefore investigators concentrate on using Meta-heuristic *** Optimization(DFO)is an effective meta-heuristic approach to resolve these problems by providing optimal ***,Meta-heuristic approaches(DFO)turn to be slower in convergence problems and need proper computational time while expanding network ***,DFO is adaptively improved as Adaptive Dragonfly Optimization(ADFO)to fit this model and re-formulated using graph-based m-connection establishment(G-𝑚𝑚cE)to overcome computational time and DFO’s convergence based problems,considerably enhancing DFO ***(G-𝑚𝑚cE),connectivity Zone(cZ)is chosen among source to destination in which optimality should be under those connected regions and ADFO is used for effective route establishment in cZ indeed of complete networking *** measure complementary features of ADFO and(G-𝑚𝑚cE),hybridization of DFO-(G-𝑚𝑚cE)is anticipated over dense circumstances with reduced energy consumption and delay to enhance network *** simulation was performed in MATLAb environment.

关键词： Routing connectivity zone ADFO mobile ad-hoc network graph-based m-connection establishment

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A New Approach to Energy Integral for Investigation of Dust-Ion Acoustic(DIA)Waves in Multi-component Plasmas with Quantum Effects in Inertia Less Electrons

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communications in Theoretical Physics 2015年第6期63卷 761-768页

作者： b.c.Kalita R.Kalita Department of Mathematics Gauhati University

Dust-ion acoustic waves are investigated in this model of plasma consisting of negatively charged dusts, cold ions and inertia less quantum effected electrons with the help of a typical energy integral. In this case, a new technique is applied formulating a differential equation to establish the energy integral in case of multi-component plasmas which is not possible in general. Dust-ion acoustic （DIA） compressive and rarefactive, supersonic and subsonic solitons of various amplitudes are established. The consideration of smaller order nonlinearity in support of the newly established quantum plasma model is observed to generate small amplitude solitons at the decrease of Mach number. The growths of soliton amplitudes and potential depths are found more sensitive to the density of quantum electrons. The small density ratio r（= 1 - f） with a little quantized electrons supplemented by the dust charges Zu and the in-deterministic new quantum parameter c2 are found responsible to finally support the generation of small amplitude solitons admissible for the model.

关键词： dust-acoustic solitary waves quantum effects

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