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Ion acoustic shock and periodic waves through Burgers equation in weakly and highly relativistic plasmas with nonextensivity

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Plasma Science and Technology 2017年第1期19卷 7-19页

作者： m G HAFEZ N c rOY m.r TALUKDEr m HOSSAIN ALI Department of of Applied mathematics University of Rajshahi Rajshahi-6205 Bangladesh Department of mathematics Chittagong University of Engineering and Technology Chittagong-4349Bangladesh Plasma Science and Technology Lab Department of Applied Physics and Electronic EngineeringUniversity of Rajshahi Rajshahi-6205 Bangladesh

A comparative study is carried out for the nonlinear propagation of ion acoustic shock waves both for the weakly and highly relativistic plasmas consisting of relativistic ions and qdistributed electrons and *** Burgers equation is derived to reveal the physical phenomena using the well known reductive perturbation *** integration of the Burgers equation is performed by the（G￠/G）-expansion *** effects of positron concentration,ion–electron temperature ratio,electron–positron temperature ratio,ion viscosity coefficient,relativistic streaming factor and the strength of the electron and positron nonextensivity on the nonlinear propagation of ion acoustic shock and periodic waves are presented graphically and the relevant physical explanations are provided.

关键词： electron-positron-ion plasmas ion acoustic shock and periodic waves weakly and highly relativistic effects Burgers equation

Assessing the potential for satellite image monitoring of seagrass thermal dynamics:for inter-and shallow sub-tidal seagrasses in the inshore Great Barrier reef World Heritage Area,Australia

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International journal of Digital Earth 2018年第8期11卷 803-824页

作者： S.r.Phinn E.m.Kovacs c.m.roelfsema r.F.canto c.j.collier L.j.mcKenzie remote Sensing research centre School of Earth and Environmental SciencesUniversity of QueenslandSt LuciaAustralia centre for Tropical Water and TErrAtic Ecosystem.research(TropWATEr) James Cook UniversityCairnsAustralia

Seagrass meadows are at increasing risk of thermal stress and recent work has shown that water temperature around seagrass meadows could be used as an indicator for seagrass *** thermal data have not been linked to the thermal properties of seagrass *** work assessed the covariation between 20 in situ average daily temperature logger measurement sites in tropical seagrass meadows and satellite derived daytime SST(sea surface temperature)from the daytime mODIS and Landsat sensors along the Great Barrier reef coast in *** significant(r2=0.787–0.939)positive covariations were found between in situ seagrass logger temperatures and mODIS SST temperature and Landsat sensor temperatures at all sites along the *** mODIS SST were consistently higher than in situ temperature at the m.jority of the sites,possibly due to the sensor’s larger pixel size and location offset from field *** thermal data were lower than field-measured SST,due to differences in measurement scales and *** refined significantly and tested over larger areas,this approach could be used to monitor seagrass health over large(106 km2)areas in a similar manner to using satellite SST for predicting thermal stress for corals.

关键词： Seagrass temperature thermal tolerance satellite sea surface temperature Landsat mODIS Great Barrier reef

Dynamic mechanical relaxation in Bulk metallic Glasses:A review

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journal of materials Science & Technology 2014年第6期30卷 523-545页

作者： j.c.Qiao j.m.Pelletier Université de Lyon CNRS France INSA-Lyon MATEIS UMR5510 F-69621 Villeurbanne France

metallic glasses have aroused considerable interest in the past decades because they exhibit fascinating properties. First, this article briefly outlines the mechanical, thermal properties and application of the metallic glasses. In addition, we focus on the dynamic mechanical relaxation behaviors, i.e. main （α） and secondary （β） relaxations, in metallic glasses. The mechanical relaxation behaviors are connected to the mechanical properties and physical properties in glassy materials. The main relaxation in glassy materials is related to the glass transition phenomenon and viscous flow. On the other hand, the β relaxation is linked to many fundamental issues in metallic glasses. In these materials relaxation processes are directly related to the plastic deformation mechanism. The mechanical relaxations, particularly, the β relaxation provides an excellent opportunity to design metallic glasses with desired physical and mechanical properties. We demonstrate the universal characteristics of main relaxation in metallic glasses. The phenomenological models and the physical theories are introduced to describe the main relaxation in metallic glasses. In parallel, we show the dependence of the α. and β relaxations on the thermal treatments in metallic glasses. Finally, we analyze the correlation between the atomic mobility and the thermo-mechanical treatments in metallic glasses. On the one hand, the atomic mobility in metallic glasses is reduced by physical aging or crystallization. On the other hand, the atomic mobility in metallic glass is enhanced by deformation （i.e. com.ression and cold rolling）. Importantly, to analyze the atomic mobility in am.rphous materials, a physical theory is introduced. This model invokes the concept of quasi-point defects, which correspond to the density fluctuations in the glassy materials.

关键词： metallic glasses mechanical properties main relaxation Secondary relaxation Physical analysis

Atmospheric pressure gliding arc discharge plasma treatments for im.roving germination, growth and yield of wheat

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Plasma Science and Technology 2018年第11期20卷 90-100页

作者： N c rOY m m HASAN A H KABIr m A rEZA m.r TALUKDEr A N cHOWDHUrY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of Rajshahi Rajshahi 6205 Bangladesh Department of Agronomy and Agricultural Extension University of Rajshahi Rajshahi 6205 Bangladesh Depatment of Botany University of Rajshahi Rajshahi 6205Bangladesh Department of Genetic Engineering and Biotechnology University of Rajshahi Rajshahi 6205Bangladesh Bangladesh council of Scientific and Industrial research Laboratory rajshahi Rajshahi 6206Bangladesh

Wheat （Triticum aestivum） seeds were treated with atmospheric pressure gliding arc discharge plasmas to investigate the effects on water absorption, seed germination rate, seedling growth and yield in wheat. The surface architectures and functionalities of the seeds were found to modify due to plasma treatments. 6 rain treatment was provided 95%-100% germination rate. For the treatment duration of 3 and 9 rain the growth activity, dry matter accumulation, leaves chlorophyll contents, longest spikes, number of spikes/spikelet and total soluble protein content in shoots were im.roved. The grain yield of wheat was increased ,--20% by 6 min treatment with H2O/O2 plasma with respect to control.

关键词： atmospheric pressure gliding arc discharge plasmas wheat germination growth im.rovement total soluble protein

Age-hardening behavior,corrosion mechanisms,and passive film structure of nanocrystalline Al-V supersaturated solid solution

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journal of materials Science & Technology 2023年第4期135卷 1-12页

作者： j.christudasjustus m.r.Felde c.S.Witharamage j.Esquivel A.A.Darwish c.Winkler r.K.Gupta Department of materials Science and Engineering North Carolina State UniversityRaleighNC 27606United States Department of chemical Biomolecular and Corrosion EngineeringThe University of AkronAkronOH 44325United States

The effect of age-hardening on microstructure,hardness,and corrosion of an Al-5at.%V alloy,produced us-ing high-energy ball milling and subsequent cold compaction,has been *** alloy exhibited a grain size below 100 nm and extremely high solid solubility of V in Al(3.1 at.%).The age-hardening was carried out at 150,200,and 250℃.The peak-aged condition of 150℃ demonstrated the highest hardness-transpired from grain refinement,precipitation,and solid solution *** corrosion re-sistance of the Al-5at.%V alloy was studied as a function of aging *** peak-aged condition retained the corrosion resistance while it deteriorated in the over-aged ***,the cor-rosion resistance of the ball-milled Al alloys in all the aging conditions was superior to that of pure *** passive film structure and origin of corrosion were studied using scanning/transmission electron mi-croscopy(S/TEm).The high corrosion resistance of the alloy was attributed to the V enrichment at the film/metal interface and deposition of V on the cathodic phases,which suppresses the dissolution of Al within the pit and therefore promotes repassivation in the early stages of corrosion.

关键词： Al alloys Nanocrystalline alloy Age-hardening Ball milling corrosion Hardness

Development of an operational land water mask for mODIS collection 6,and influence on downstream data products

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International journal of Digital Earth 2017年第2期10卷 207-218页

作者： m.L.carroll c.m.Dimiceli j.r.G.Townshend r.A.Sohlberg A.I.Elders S.Devadiga A.m.Sayer r.c.Levy NASA/GSFc Biospheric Sciences Laboratory GreenbeltMDUSA Science Systems and Applications Inc. LanhamMDUSA Department of Geographical Sciences University of MarylandCollege ParkMDUSA Atmospheric Oceanic and Earth SciencesGeorge Mason UniversityFairfaxVAUSA NASA/GSFc Terrestrial Information Systems Laboratory GreenbeltMDUSA fGoddard Earth Sciences Technology and research Universities Space Research AssociationGreenbeltMDUSA NASA/GSFc climate and radiation Laboratory GreenbeltMDUSA

Data from the moderate resolution Imaging Spectro-radiometer(mODIS)on-board the Earth Observing System Terra and Aqua satellites are processed using a land water mask to determine when an algorithm no longer needs to be run or when an algorithm needs to follow a different *** the fourth reprocessing(collection 6(c6))the mODIS team.replaced the 1 km water mask with a 500 m water mask for im.roved representation of the continental *** new water mask represents m.re small water bodies for an overall increase in water surface from 1%to 2%of the continental *** this is still a small fraction of the overall global surface area the increase is m.re dramatic in certain areas such as the Arctic and Boreal regions where there are dramatic increases in water surface area in the new *** products generated by the on-going c6 reprocessing using the new land water mask show significant impact in areas with high concentrations of change in the land water *** differences between the collection 5(c5)and c6 water masks and the impact of these differences on the mOD04 aerosol product and the mOD11 land surface temperature product are shown.

关键词： Earth observation image processing land cover remote sensing water resources

Use of wild trout for PBDE assessment in freshwater environments: review and summ.ry of critical factors

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Em.rging contaminants 2015年第1期1卷 54-63页

作者： juan m.ríos Nerina B.Lana Paula Berton Néstor F.ciocco jorgelina c.Altam.rano Laboratorio de Química Ambiental Instituto Argentino de NivologíaGlaciología y Ciencias Ambientales(IANIGLA)-CONICETMendozaP.O Box 1315500 MendozaArgentina Facultad de ciencias Exactas y Naturales Universidad Nacional de CuyoPadre J.Contreras 13005500 MendozaArgentina Instituto Argentino de Investigaciòn de ZonasÁridas(IADIZA)-cONIcET MendozaP.O Box 5075500 MendozaArgentina

certain wild animals represent sentinels to address issues related to environmental pollution,since they can provide integrative data on both pollutant exposure and biological *** their technological benefits,PBDEs are considered a threat to environmental health due to their persistence,toxicity,and capacity to be *** pollutants have been found geographically widespread in fish,particularly in predator species such as *** aim of this work is to critically review the applicability and usefulness of wild trout for assessing PBDEs in freshwater *** reports include data from highly industrialized areas as well as areas from.remote regions with relatively low human activity,including European and North Am.rican great lakes and freshwater environments in Europe,Greenland,subarctic areas and Patagonia,respectively.A summ.ry of relevant factors were grouped into organism-specific factors(food habits,age,size,lipid content,sex and reproduction,tissue type,mechanism of contaminant uptake and metabolism),and PBDE levels in the surrounding environment(sediment).Five wild trout species[rainbow trout(Oncorhynchus mykiss),brown trout(Salmo trutta),lake trout(Salvelinus namaycush),arctic char(Salvelinus alpinus),and brook trout(Salvelinus fontinalis)],collected worldwide within the 1994 to present time frame,were *** techniques(principal component analysis-PcA)and mapping approach,showed clear differences in geographic distribution patterns of PBDE levels in trout depending on the region studied:wild trout from European and North Am.rican great lakes have the highest PBDE *** pattern could be due to high industrial activity at these locations.A correlational approach used to explore intraspecific relationships between PBDE levels and m.rphometry,showed positive relationships only for brown ***,brown trout showed the highest trout-to-sediment ratios,which is suggestive of a relatively greater capa

关键词： critical factors Freshwater environments PBDE Trout Global hotspots

OH and O radicals production in atmospheric pressure air/Ar/H_2O gliding arc discharge plasma jet

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Plasma Science and Technology 2017年第12期19卷 71-80页

作者： N c rOY m.r TALUKDEr A N cHOWDHUrY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi 6205Bangladesh Bangladesh council of Scientific and Industrial research Laboratory rajshahi Rajshahi 6206Bangladesh

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to m.re effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n *** productions of OH and O are decreasing with increasing air flow rate due to removal of joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.

关键词： reactive oxygen species(rOS) optical emission spectroscopy(OES) gliding arc discharge plasma kinetics broadening mechanism

Application of a long short-term mem.ry for deconvoluting conductance contributions at charged ferroelectric domain walls

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npj computational materials 2020年第1期6卷 319-325页

作者： Theodor S.Holstad Trygve m.ræder Donald m.Evans Didirk r.Småbråten Stephan Krohns jakob Schaab Zewu Yan Edith Bourret Antonius T.jvan Helvoort Tor Grande Sverre m.Selbach joshua c.Agar Dennis meier Department of materials Science and Engineering Norwegian University of Science and Technology(NTNU)7491 TrondheimNorway Department of materials Science and Engineering Lehigh UniversityBethlehemPA 18015USA Experimental Physics V Center for Electronic Correlations and MagnetismUniversity of Augsburg86159 AugsburgGermany Department of materials ETH Zurich8093 ZürichSwitzerland materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Physics ETH Zurich8093 ZürichSwitzerland Department of Physics Norwegian University of Science and Technology(NTNU)7491 TrondheimNorway

Ferroelectric domain walls are promising quasi-2D structures that can be leveraged for miniaturization of electronics components and new mechanisms to control electronic signals at the *** the significant progress in experiment and theory,however,most investigations on ferroelectric domain walls are still on a fundamental level,and reliable characterization of em.rgent transport phenomena remains a challenging task.

关键词： walls ferroelectric conductance