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Arsenic contamination of groundwater:A global synopsis with focus on the Indian Peninsula

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Geoscience Frontiers 2021年第3期12卷 1-18页

作者： e.Shaji M.Santosh K.v.Sarath Pranav Prakash v.Deepchand B.v.Divya Department of Geology University of KeralaKariavattom CampusTrivandrum 695581India School of earth Sciences and Resources China University of Geosciences(Beijing)29 Xueyuan RoadBeijing 100083China Department of earth Science University of AdelaideAdelaideSA 5005Australia

More than 2.5 billion people on the globe rely on groundwater for drinking and providing high-quality drinking water has become one of the major challenges of human *** groundwater is considered as safe,high concentrations of heavy metals like arsenic(As)can pose potential human health concerns and *** this paper,we present an overview of the current scenario of arsenic contamination of groundwater in various countries across the globe with an emphasis on the Indian *** several newly affected regions reported during the last decade,a significant increase has been observed in the global scenario of arsenic *** is estimated that nearly 108 countries are affected by arsenic contamination in groundwater with concentration beyond maximum permissible limit of 10 ppb recommended by the World Health *** highest among these are from Asia(32)and europe(31),followed by regions like Africa(20),North America(11),South America(9)and Australia(4).More than 230 million people worldwide,which include 180 million from Asia,are at risk of arsenic *** Asian countries,Bangladesh,India,Pakistan,China,Nepal,vietnam,Burma,Thailand and Cambodia,are the most *** India,20 states and 4 Union Territories have so far been affected by arsenic contamination in *** attempt to evaluate the correlation between arsenic poisoning and aquifer type shows that the groundwater extracted from unconsolidated sedimentary aquifers,particularly those which are located within the younger orogenic belts of the world,are the worst *** than 90%of arsenic pollution is inferred to be *** infer that alluvial sediments are the major source for arsenic contamination in groundwater and we postulate a strong relation with plate tectonic processes,mountain building,erosion and *** consumption of arsenic-contaminated groundwater results in severe health issues like skin,lung,kidney and bladder ca

关键词： Arsenic contamination Groundwater Indo-Gangetic alluvium Orogenic belts Global tectonics Asia

ADSORPTION AND ReLeASING PROPeRTIeS OF BeAD CeLLULOSe

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Chinese Journal of Polymer Science 2004年第5期22卷 417-423页

作者： A.Morales e.Bordallo v.Leon J.Rieumont FacultyofChemistryandPharmacy CentralUniversityofLasVillas.Camajuanikm51／2VillaClaraSantaClara54830Cuba Research-ProductionPlantCuba9 QuivicanHavanaCuba FacultyofChemistry HavanaUniversityAveZapataandGHavana10400Cuba

The adsorption of some dyes on samples of bead cellulose obtained in the Unit of Research-Production 'Cuba 9' was studied. Methylene blue, alizarin red and congo red fitted the adsorption isotherm of Langmuir. Adsorption kinetics at pH = 6 was linear with the square root of time indicating the diffusion is the controlling step. At pH = 12 a non-Fickian trend was observed and adsorption was higher for the first two dyes. experiments carried out to release the methylene blue occluded in the cellulose beads gave a kinetic behavior of zero order. The study of cytochrome C adsorption was included to test a proteinic material. Crosslinking of bead cellulose was performed with epichlorohydrin decreasing its adsorption capacity in acidic or alkaline solution.

关键词： Bead cellulose Adsorption Isotherms Kinetics of adsorption Dyes

Late Mesozoic topographic evolution of western Transbaikalia:evidence for rapid geodynamic changes from the Mongol-Okhotsk collision to widespread rifting

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Geoscience Frontiers 2020年第5期11卷 1695-1709页

作者： A.v.Arzhannikova e.I.Demonterova M.Jolivet S.G.Arzhannikov e.A.Mikheeva A.v.Ivanov v.B.Khubanov L.A.Pavlova Institute of the earth’s Crust Russian Academy of SciencesSiberian BranchIrkutskRussia Laboratoire Geosciences Rennes CNRS-UMR6118Universite de RennesRennesFrance Geological Institute Russian Academy of SciencesSiberian BranchUlan-UdeRussia A.P.vinogradov Institute of Geochemistry Siberian Branch of the Russian Academy of SciencesIrkutskRussia

The Mesozoic geodynamic evolution of Transbaikalia has been largely controlled by the scissors-like closure of the Mongol-Okhotsk Ocean that separated Siberia from Mongolia-North China *** the oceanic closure,the tectonic evolution of that region was characterized by collisional uplift and subsequent extension that gave rise to the formation of metamorphic core *** complex tectonic setting prevailed simultaneously between 150 Ma and 110 Ma both in Transbaikalia,North Mongolia,and within the North China *** paleobotanical and paleontological data show that the oldest Mesozoic basins had formed in western Transbaikalia before the estimated age of extension *** no precise geochronological age is available for the onset of extension in *** Tugnuy Basin,as probably the oldest Mesozoic basin in western Transbaikalia,is a key obj ect to date the onset of extension and following changes in tectonic *** this study,U-Pb(LA-ICP-MS)dating of detrital zircons from three key Jurassic sediment formations of the Tugnuy Basin are used to identify the potential source areas of the sediments,understand the changes in sediment routing and provide insights on the topographic evolution of western *** results show several significant changes in tectonic regime after the closure of the Mongol-Okhotsk Ocean.A wide uplifted plateau formed during the closure of the Mongol-Okhotsk Ocean,determining the early Jurassic drainage system reaching the Angaravitim batholith to the north and shedding sediments to the continental margin to the *** following collisional event at the end of the early Jurassic led to the uplift of the collision zone,which partially inverted the drainage system toward the North.A strike-slip displacement induced by the oblique collision initiated some of the early Transbaikalian depressions,such as the Tugnuy Basin at about 168 Ma.A phase of basin inversion,marked by folding and ero

关键词： U–Pb detrital zircons dating Topographic evolution Mongol–Okhotsk collision Transbaikalia

Concrete damage diagnosed using the non-classical nonlinear acoustic method

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Chinese Physics B 2009年第5期18卷 1898-1905页

作者：周到刘晓宙龚秀芬 Nazarov v e 马力 Key Laboratory of Modern Acoustics Ministry of EducationInstitute of AcousticsNanjing University Institute of Applied Physics Russian Academy of ScienceRussian Federation Institute of Acoustics Chinese Academy of Sciences

It is known that the strength of concrete is seriously affected by damage and cracking. In this paper, six concrete samples under different damage levels are studied. The experimental results show a linear dependence of the resonance frequency shift on strain amplitude at the fundamental frequency, and approximate quadratic dependence of the am- plitudes of the second and third harmonics on strain amplitude at the fundamental frequency as well. In addition, the amplitude of the third harmonics is shown to increase with the increase of damage level, which is even higher than that of the second harmonics in samples with higher damage levels. These are three properties of non-classical nonlinear acoustics. The nonlinear parameters increase from 106 to 108 with damage level, and are more sensitive to the damage level of the concrete than the linear parameters obtained by using traditional acoustics methods. So, this method based on non-classical nonlinear acoustics may provide a better means of non-destructive testing （NDT） of concrete and other porous materials.

关键词： concrete non-classical nonlinear acoustics non-destructive testing (NDT) crack

effect of Nitrogen Doping on the electrical Properties of 3C-SiC Thin Films for High-Temperature Sensors Applications

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Acta Metallurgica Sinica(english Letters) 2014年第1期27卷 168-174页

作者： H.K.e.Latha A.Udayakumar v.Siddeswara Prasad Department of Instrumentation Technology Siddaganga Institute of Technology Materials Science Division Council of Scientific and Industrial Research-National Aerospace Laboratories

3C-SiC is a promising structural material for piezoresistive sensors used in high-temperature applications. For sensor development, the preparation of sensor materials and study of its electrical properties, such as resistivity, barrier height of grain boundaries, and temperature coefficient of resistivity, are important in addition to structural properties and these have to be optimized. In the present work, 3C-SiC thin film with in situ doping of nitrogen is prepared through low- pressure chemical vapor deposition by using methyl trichloro silane, ammonia, and hydrogen as precursors. electrical properties of deposited 3C-SiC thin films with varying nitrogen doping concentration through four probe technique are studied. Atomic force microscopy investigations are carried out to study the grain size on and average root-mean-squared roughness 3C-SiC thin films. A decrease in the degree of crystallinity is observed in nitrogen-doped 3C-SiC thin films. The sheet resistivity of nitrogen-doped 3C-SiC thin film is found to decrease with increase in temperature in the range from 303 to 823 K. The sheet resistivity, average temperature coefficient of resistance, and barrier height of the grain boundaries of film doped with 17 at.% of nitrogen are 0.14 cm, -1.0 x 10-n/K, and 0.01 ev, respectively. Comparing all the nitrogen-doped 3C-SiC thin films, the film doped with 17 at.% of nitrogen exhibits an improved structural and electrical properties and it can be used as sensing material for high-temperature applications.

关键词： Low-pressure chemical vapor deposition (LPCvD) 3C-SiC thin film Resistivity Barrier height of grain boundaries: Temperature coefficient of resistivitv (TCR)

emission of high-energy alpha particles in nuclear reactions of ^(48)Ca and ^(56)Fe ions on ^(181)Ta and ^(238)U targets

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Chinese Physics C 2022年第11期46卷 177-194页

作者： Yu.e.Penionzhkevich v.v.Samarin S.M.Lukyanov v.A.Maslov M.A.Naumenko Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear ResearchDubna 141980Russia Department of experimental Methods in Nuclear Physics National Research Nuclear UniversityMoscow 115409Russia Department of Nuclear Physics Dubna State UniversityDubna 141982Russia

The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are *** measurements were performed using the high-resolution magnetic analyzer MAvR with beams of ^(48)Ca(280 Mev)and ^(56)Fe(320 and 400 Mev)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent Schrödinger equation *** analysis of the obtained experimental data was carried out within the model of moving sources modified to consider the kinematic limits for two-body and three-body exit channels.

关键词： alpha particle energy spectra two-and three-body kinematic limits model of moving sources time-dependent Schrodinger equation

evaluation of the cracking and aging susceptibility of asphalt mixtures using viscoelastic properties and master curve parameters

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Journal of Traffic and Transportation engineering(english edition) 2022年第1期9卷 106-119页

作者： Runhua Zhang Jo e.Sias eshan v.Dave Department of Civil and environmental engineering University of New HampshireDurhamNH 03824USA

Aging can significantly affect the performance of asphalt mixtures, causing increase in stiffness, reduction in relaxation capability and increase in cracking susceptibility. It is also well known that fundamental viscoelastic properties are used for design and modelling of asphalt mixtures and pavement structures to addressing rutting, fatigue and thermal cracking concerns. The objective of this paper is to study how the viscoelastic properties of asphalt mixture change over time, and evaluate and identify the cracking and aging susceptibility of asphalt mixtures with different mix variables during material selection and mixture design. Ten mixtures are evaluated using different laboratory conditioning protocols to simulate a range of aging levels in the field. The complex modulus test is then conducted on the lab aged mixtures to measure the viscoelastic properties in order to construct the dynamic modulus and phase angle master curves. The mixture Glover-Rowe(G-Rm) parameter and the shape parameters of the dynamic modulus and phase angle master curves, including inflection point frequency(-β/γ), difference between the glassy modulus and the inflection point modulus(γ), peak value of phase angle(a) and the horizontal position(frequency) of the peak phase angle value(c), are determined and evaluated for the mixtures with different aging conditions and mix variables. The study indicates the ability of the G-Rmparameter and all the master curve shape parameters to capture the effect of different aging conditions on linear viscoelastic mixture properties, as well as the cracking and aging susceptibility of asphalt mixtures.

关键词： Asphalt mixture viscoelastic properties Complex modulus and phase angle master curve Master curve shape parameters Aging susceptibility Cracking susceptibility

Translating Difference:Reflections on the Interface between Novelistic Discourse and World Literature

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Journal of Foreign Languages and Cultures 2024年第1期8卷 16-30页

作者： e.v.RAMAKRISHNAN Central University of Gujarat

The present essay examines two moments from the evolution of the modern Malayalam novel,in relation to the reception of two classics in world literature,namely victor Hugo's Les Miserables translated into Malayalam between 1925 and 1927 and Garcia Marquez's One Hundred Years of Solitude translated in *** translation of Hugo's novel energized the scene of Malayalam fiction by infusing new modes of representation and widening the intellectual horizons of writers in general,and novelists in *** echoes of Les Miserables could be heard in Malayalam fiction well into the *** struggles against colonial and feudal authorities in Kerala,provided a fertile context for the imaginative interpretation of Hugo's humanist *** paper illustrates this point through close readings of critical essays,autobiographical narratives and debates on the nature of *** fascination of Malayali readers with Garcia Marquez has resulted in the translation of his entire corpus into *** realism as pioneered by Garcia Marquez liberated the Malayalam novelistic narrative from social realist and modernist *** colonial disruption of oral narratives,the consequent cultural amnesia and the struggle to reclaim one's forgotten past are themes that struck a chord in Malayalam writers of *** a detailed discussion of the novel,Moustache by ***,the interface between novelistic discourse and world literature is mapped in the latter part of the essay.

关键词： Malayalam literature translation difference world literature magic realism caste resistance

Chemical behaviour of Al/Cu nanoparticles in water

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Progress in Natural Science:Materials International 2015年第1期25卷 1-5页

作者： N.v.Svarovskaya A.v.Berenda O.v.Bakina e.A.Glazkova A.S.Lozhkomoev e.G.Khorobraya v.v.Domashenko M.I.Lerner A.N.Fomenko Institute of Strength Physics and Materials Science Siberian Branch of the Russian Academy of Sciences (ISPMS SB RAS)2/4 pr.Akademichesky ave. Tomsk 634021 Russia National Research Tomsk State University (TSU) 36 Lenina ave. 634050 Tomsk Russia National Research Tomsk Polytechnic University (TPU) 30 Lenina ave. 634050 Tomsk Russia

Bimetallic Al/Cu nanoparticles with Al/Cu composition 10:90, 20:80, 40:60 were produced by method of simultaneous electrical explosion of metal pairs in the argon atmosphere. Nanopowders containing 20% and 40% (mass) of aluminum interacted with water at 40–70 ℃ and formed composite particles that were porous structures of nanopetal pseudoboehmite with nanosized copper-containing inclusions inside. Aluminum in nanopowder with Al/Cu composition 10:90 did not react with water, as far as it is in the phase of intermetallic compounds Сu Al2and С*** produced can be used as an active component of antibacterial agents.

关键词： Nanopowders Bimetallic nanoparticles Composite nanoparticles