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Environmental monitoring of Bombetoka Bay and the Betsiboka Estuary,madagascar,Using multi-temporal Satellite Data

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Journal of Earth Science 2010年第2期21卷 210-226页

作者： Tsilavo Raharimahefa Timothy m Kusky Department of Earth Sciences Laurentian University Three Gorges Research Center for Geo-hazard Ministry of EducationChina University of Geosciences(Wuhan) State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences(Wuhan)

The causes and consequences of soil erosion in madagascar have been the focus of recent environmental debates. The Betsiboka, madagascar＇s largest river stretching 600 km from the high central plateau to the northwest coast on the mozambique Channel, is a major conduit for transporting lateritic soils and sediments derived from the highlands of Central madagascar to the sea. These en- trained lateritic sediments color the river a blood-red hue, as if the life of the island is being drained away. In this study, Landsat visible and near infrared spectral bands are used to map the underwater sediments especially under the sea and in the interface between seawater and freshwater. Band color composites, single bands and band ratios are used to improve the detection of underwater sediments including sand bars and delta lobes. We show the evolution of the bay, coastline, delta, and change detection results derived from Landsat satellite images recorded in 1973, 1989, 1999, 2000 and 2003, respectively. Results indicate that sedimentary transport and suspension in Bombetoka Bay has significantly changed during the past 30 years, with a dramatic increase in the amount of sediment moved by the river, and deposited in the estuary and in offshore delta lobes. These changes have adversely affected agriculture, fisheries, and transportation for one of madagascar＇s largest ports. The changes are attributed to increased erosion following large-scale deforestation, bush fires, and overgrazing in the river basin.

关键词： environment monitoring madagascar delta remote sensing Landsat.

The geology, structure and mineralisation of the Oyu Tolgoi porphyry copper-gold-molybdenum deposits, mongolia： A review

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Geoscience Frontiers 2016年第3期7卷 375-407页

作者： T.m.(mike) Porter Porter CeoConsultancy Ply Ltd. Linden Park 5065 SA Australia

The Oyu Tolgoi cluster of seven porphyry Cu-Au-mo deposits in southern mongolia,define a narrow,linear,12 km long,almost continuously mineralised trend,which contains in excess of 42 mt of Cu and1850 t of Au,and is among the largest high grade porphyry Cu-Au deposits in the *** deposits lie within the Gurvansayhan island-arc terrane,a fault bounded segment of the broader Silurian to Carboniferous Kazakh-mongol arc,located towards the southern margin of the Central Asian Orogenic Belt,a collage of magmatic arcs that were periodically active from the late Neoproterozoic to PermoTriassic,extending from the Urals mountains to the Pacific *** at Oyu Tolgoi is associated with multiple,overlapping,intrusions of late Devonian（～372 to 370 ma） quartzmonzodiorite intruding Devonian（or older） juvenile,probably intra-oceanic arc-related,basaltic lavas and lesser volcaniclastic rocks,unconformably overlain by late Devonian（～370 ma） basaltic to dacitic pyroclastic and volcano sedimentary *** quartz-monzodiorite intrusions range from earlymineral porphyritic dykes,to larger,linear,syn-,late- and post-mineral dykes and *** was deposited within syn-mineral quartz-monzodiorites,but is dominantly hosted by augite basalts and to a lesser degree by overlying dacitic pyroclastic *** ore deposition,an allochthonous plate of older Devonian（or pre-Devonian） rocks was overthrust and a post-ore biotite granodiorite intruded at～365 *** is characterised by varying,telescoped stages of intrusion and *** A-type quartz veined dykes were followed by Cu-Au mineralisation associated with potassic alteration,mainly K-feldspar in quartz-monzodiorite and biotite-magnetite in basaltic *** reflux of cooled,late-magmatic hydrothermal fluid resulted in intense quartz-sericite retrograde alteration in the upper parts of the main syn-mineral intrusions,and an equivalent chlorite-muscovite/illite-hematite assemblage in bas

关键词： Tectonic setting Porphyry copper-gold-molybdenum deposit High sulphidation Geology Alteration Structure

Evolution of Dissipative Anisotropic Expansion-Free Axial Fluids

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Communications in Theoretical Physics 2015年第8期64卷 139-144页

作者： m.Sharif Zunaira Nasir Department of mathematics University of the Punjab Quaid-i-Azam Campus

A general study of non-static restricted class of axial system with anisotropic dissipative expansion-free fluid under geodesic condition is carried out. It is found that expansion-free model must be dissipative under geodesic condition to preserve axial symmetry. We also investigate this system without geodesic condition. Finally, the role of dissipation is explored via transport equation.

关键词： general relativity dissipative systems analytical

Ha Line Polarization in the 2B/X4.8 Flare of 2002 July 23

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Chinese Journal of Astronomy and Astrophysics 2003年第3期3卷 266-276页

作者： ZhiXu N.m.Firstova DepartmentofAstronomy NanjingUniversityNanjing210093 InstituteofSolar-TerrestrialPhysics RussianAcademyofSciencesSiberianDivisionRussia

On 2002 July 23, a 2B/X4.8 flare was observed in the Hα line spec-tropolarimetrically by the Large Solar Vacuum Telescope of Baikal AstrophysicalObservatory. Linear polarization of 3%-10% was detected in the Hα line, particu-larly where the line showed central reversal. The linear polarization is mainly radialon the solar disk and appears at the impulsive phase of the hard X-ray and γ-raybursts. It is limited to some relatively small regions of the flare. The polarizationin a limited small region (～ 4″ - 5″) changed its direction within a short period oftime (～ 10s).

关键词： Polarization - line: profile - Sun: flare

Effect　of　Ballistic-Type　Hot　Atom　Adsorption　mechanism　on　the　Phase　Diagram　of　monomer　Dimer　CO-O2　Surface　Catalytic　Reaction：　A　monte　Carlo　Simulation

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Chinese Physics Letters 2004年第6期21卷 1171-1174页

作者： m.Khalid K.m.Khan A.U.Qaisrani Q.N.malik DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan NuclearPhysicsDivision PakistanInstituteofNuclearScienceandTechnology(PINSTECH)P.O.NiloreIslamabadPakistan

We investigate the effect of the ballistic mechanism on the phase diagram using a square surface. While using this mechanism whenever an O2 molecule hits a randomly vacant selected site, the molecule breaks up into atomic form and then executes a ballistic flight. The paths of the two oxygen atoms are taken exactly to be opposite to each other, ***-parallel, and the ranges of the atoms are taken to be equal, *** may fly up to 1 or 1.414 or 2 of the atomic spacing from the site of impact. Four cases have been studied on the basis of the range of hot atoms. The range of the hot oxygen atoms executing a ballistic flight might be up to the first nearest neighbourhood (1 atomic spacing from the site of impact), the second nearest neighbourhood (1.414 atomic spacing from the site of impact), the third nearest neighbourhood (2 atomic spacing from the site of impact), known as cases a, b, and c, respectively, while for case d the range of the oxygen atoms executing the ballistic flight might be up to 1 atomic spacing or 1.414 atomic spacing or 2 atomic spacing from the site of impact. The steady reactive window is observed and the continuous transition disappears. As soon as the CO partial pressure departs from zero, the production of CO2 is observed, which clearly verifies the experimental observation.

关键词： Oxygen

Adult to adult living related liver transplantation: Where do we currently stand?

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World Journal of Gastroenterology 2012年第46期18卷 6729-6736页

作者： Erica m Carlisle Giuliano Testa Department of Surgery Baylor University Medical Center

Adult to adult living donor liver transplantation (AALDLT) was first preformed in the United States in 1997. The procedure was rapidly integrated into clinical practice, but in 2002, possibly due to the first widely publicized donor death, the number of living liver donors plummeted. The number of donors has since reached a steady plateau far below its initial peak. In this review we evaluate the current climate of AALDLT. Specifically, we focus on several issues key to the success of AALDLT: determining the optimal indications for AALDLT, balancing graft size and donor safety, assuring adequate outflow, minimizing biliary complications, and maintaining ethical practices. We conclude by offering suggestions for the future of AALDLT in United States transplantation centers.

关键词：肝移植成人活体临床实践职业道德适应症并发症美国

Food habits of striped hyena(Hyaena hyaena) in a semi-arid conservation area of India

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Journal of Arid Land 2015年第6期7卷 860-866页

作者： m Shamshad ALAm Jamal A KHAN Department of Wildlife Sciences Aligarh Muslim University

Striped hyena（Hyaena hyaena） is a near-threatened large carnivore known to occur in arid and semi-arid landscapes in many parts of the world. Its population is declining globally and ecological information is required urgently to meet their conservation needs. We studied the diet pattern of the striped hyena in the semi-arid Gir National Park and Sanctuary（GNPS）, western India. Prey items eaten by the striped hyena were identified from scats. Around 44.4% scats represented single to three mammalian preys while 55.6% of them represented four preys to seven preys. A variety of food items were identified including mammals, birds, insects and vegetable matters. Scats analysis showed that 63.91% diet of striped hyena was contributed by wild prey items, 20.94% by domestic prey and 3.31% by birds, whereas vegetable and insects contributed 9.92% and 1.93%, respectively. Diet diversity of the striped hyena computed by the Shannon-Weiner Index（H） was found to be 2.64. The presence of domestic mammals in the scat remains implied that the striped hyena might frequently visit human habitation in search for food and hence, a potential conflict between human and wildlife might arise. Reducing the dependence of hyena on domestic livestock is a challenge to ensure the survival of striped hyena outside the protected area.

关键词： diet pattern Gir National Park and Sanctuary Hyaena hyaena scat analysis

Inelastic Cotunneling Current and Shot Noise of an Interacting Quantum Dot with Ferromagnetic Correlations

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Communications in Theoretical Physics 2007年第12期48卷 1099-1106页

作者： Norman J.m.Horing Department of Physics and Engineering Physics Stevens Institute of TechnologyHobokenNew Jersey 07030USA

We explore inelastic cotunneling through a strongly Coulomb-blockaded quantum dot attached to twoferromagnetic leads in the weak coupling limit using a generic quantum Langevin equation *** first developa B1och-type equation microscopically to describe the cotunneling-induced spin relaxation dynamics,and then developexplicit analytical expressions for the local magnetization,current,and its *** this basis,we predict a novelzero-bias anomaly of the differential conductance in the absence of a magnetic field for the anti-parallel configuration,and asymmetric peak splitting in a magnetic ***,for the same system with large polarization,we find a negativezero-frequency differential shot noise in the low positive bias-voltage region. All these effects are ascribed to rapidspin-reversal due to underlying spin-flip cotunneling.

关键词： quantum dot spin polarized tunneling cotunneling

Effect of Cerium Doping on microstructure and Dielectric Properties of BaTiO_3 Ceramics

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Journal of materials Science & Technology 2011年第8期27卷 759-763页

作者： Sabina Yasmin Shamima Choudhury m.A. Hakim A.H. Bhuiyan m.J. Rahman Department of Physics University of Dhaka materials Science Division Atomic Energy Centre Department of Physics Bangladesh University of Engineering and Technology

A solid state reaction method was used to synthesize barium titanate （BT） and barium cerium titanate （BCT） ceramics at sintering temperature of 1473 K for 4 h. The effect of cerium （Ce） on the structure, microstructure and dielectric properties of BCT was investigated. The scanning electron microscopy （SEm） investigations revealed that the grain size increases with increasing Ce content. The X-ray diffraction （XI^D） patterns showed mostly the BT phase, where the lattice parameter decreased with the addition of Ce. The temperature dependence of dielectric constant showed decrease in the phase transition temperature with higher Ce content. The dielectric constant decreased slightly with increasing frequency. The direct current （dc） density-voltage characteristics of the ceramics showed ohmic behavior for both the BT and BCT. As the temperature increased, the dc resistivity of the ceramics decreased. The activation energy increased with increasing Ce content.

关键词： Cerium doped Ba1-xCexTiO3 Dielectric constant Current density